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ASASSN-14ko is a recently discovered periodically flaring transient at the center of the AGN ESO 253-G003 with a slowly decreasing period. Here we show that the flares originate from the northern, brighter nucleus in this dual-AGN, post-merger system. The light curves for the two flares that occurred in May 2020 and September 2020 are nearly identical over all wavelengths. For both events, Swift observations showed that the UV and optical wavelengths brightened in unison. The effective temperature of the UV/optical emission rises and falls with the increase and subsequent decline in the luminosity. The X-ray flux, in contrast, first rapidly drops over $\sim$2.6 days, rises for $\sim$5.8 days, drops again over $\sim$4.3 days and then recovers. The X-ray spectral evolution of the two flares differ, however. During the May 2020 peak the spectrum softened with increases in the X-ray luminosity, while we observed the reverse for the September 2020 peak., 12 pages, 6 figures, and 1 table. Submitted to ApJ, comments welcome

Full list of authors: Rommel, F. L.; Braga-Ribas, F.; Desmars, J.; Camargo, J. I. B.; Ortiz, J. L.; Sicardy, B.; Vieira-Martins, R.; Assafin, M.; Santos-Sanz, P.; Duffard, R.; Fernández-Valenzuela, E.; Lecacheux, J.; Morgado, B. E.; Benedetti-Rossi, G.; Gomes-Júnior, A. R.; Pereira, C. L.; Herald, D.; Hanna, W.; Bradshaw, J.; Morales, N. Brimacombe, J.; Burtovoi, A.; Carruthers, T.; de Barros, J. R.; Fiori, M.; Gilmore, A.; Hooper, D.; Hornoch, K.; Jacques, C.; Janik, T.; Kerr, S.; Kilmartin, P.; Winkel, Jan Maarten; Naletto, G.; Nardiello, D.; Nascimbeni, V.; Newman, J.; Ossola, A.; Pál, A.; Pimentel, E.; Pravec, P.; Sposetti, S.; Stechina, A.; Szakáts, R.; Ueno, Y.; Zampieri, L.; Broughton, J.; Dunham, J. B.; Dunham, D. W.; Gault, D.; Hayamizu, T.; Hosoi, K.; Jehin, E.; Jones, R.; Kitazaki, K.; Komžík, R.; Marciniak, A.; Maury, A.; Mikuž, H.; Nosworthy, P.; Fábrega Polleri, J.; Rahvar, S.; Sfair, R.; Siqueira, P. B.; Snodgrass, C.; Sogorb, P.; Tomioka, H.; Tregloan-Reed, J.; Winter, O. C., Context. Trans-Neptunian objects (TNOs) and Centaurs are remnants of our planetary system formation, and their physical properties have invaluable information for evolutionary theories. Stellar occultation is a ground-based method for studying these distant small bodies and has presented exciting results. These observations can provide precise profiles of the involved body, allowing an accurate determination of its size and shape. Aims. The goal is to show that even single-chord detections of TNOs allow us to measure their milliarcsecond astrometric positions in the reference frame of the Gaia second data release (DR2). Accurate ephemerides can then be generated, allowing predictions of stellar occultations with much higher reliability. Methods. We analyzed data from various stellar occultation detections to obtain astrometric positions of the involved bodies. The events published before the Gaia era were updated so that the Gaia DR2 stellar catalog is the reference, thus providing accurate positions. Events with detection from one or two different sites (single or double chord) were analyzed to determine the event duration. Previously determined sizes were used to calculate the position of the object center and its corresponding error with respectto the detected chord and the International Celestial Reference System propagated Gaia DR2 star position. Results. We derive 37 precise astrometric positions for 19 TNOs and four Centaurs. Twenty-one of these events are presented here for the first time. Although about 68% of our results are based on single-chord detection, most have intrinsic precision at the submilliarcsecond level. Lower limits on the diameter of bodies such as Sedna, 2002 KX14, and Echeclus, and also shape constraints on 2002 VE95, 2003 FF128, and 2005 TV189 are presented as valuable byproducts. Conclusions. Using the Gaia DR2 catalog, we show that even a single detection of a stellar occultation allows improving the object ephemeris significantly, which in turn enables predicting a future stellar occultation with high accuracy. Observational campaigns can be efficiently organized with this help, and may provide a full physical characterization of the involved object, or even the study of topographic features such as satellites or rings. © 2020 ESO., This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - Brasil (CAPES) - Finance Code 001 and the National Institute of Science and Technology of the e-Universe project (INCT do e-Universo, CNPq grant 465376/2014-2). The following authors acknowledge the respective CNPq grants: F.B.-R. 309578/2017-5; R.V.-M. 304544/2017-5, 401903/2016-8; J.I.B.C. 308150/2016-3; M.A. 427700/2018-3, 310683/2017-3, 473002/2013-2; O.C.W. 305210/2018-1. The following authors acknowledge the respective grants: B.E.M. thanks the CAPES/Cofecub-394/2016-05 grant; G.B-R. acknowledges CAPES-FAPERJ/PAPDRJ grant E26/203.173/2016; M.A. acknowledges FAPERJ grant E-26/111.488/2013; A.R.G.Jr acknowledges FAPESP grant 2018/11239-8; O.C.W. and R.S. acknowledge FAPESP grant 2016/24561-0. D.N. acknowledges support from the French Centre National d'Etudes Spatiales (CNES). K.H. and P.P. were supported by the project R.V.O.: 67985815. A.P. and R.S. received support from the K-125015 grant of the National Research, Development and Innovation Office (NKFIH, Hungary). Partial funding of the computational infrastructure and database servers are received from the grant KEP-7/2018 of the Hungarian Academy of Sciences. Some of the results were based on observations taken at the 1.6m telescope on Pico dos Dias Observatory of the National Laboratory of Astrophysics (LNA/Brazil). Some data are based on observations collected at the Copernicus and Schmidt telescopes (Asiago, Italy) of the INAF-Astronomical Observatory of Padova. This work was carried out within the "Lucky Star" umbrella that agglomerates the efforts of the Paris, Granada and Rio teams, which is funded by the European Research Council under the European Community's H2020 (ERC Grant Agreement No. 669416). This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. TRAPPIST is a project funded by the Belgian FNRS under grant FRFC 2.5.594.09.F and the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. E.J. is a FNRS Senior Research Associate. We would like to acknowledge financial support by the Spanish grant AYA-RTI2018-098657-JI00 "LEO-SBNAF" (MCIU/AEI/FEDER, U.E.) and the financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). Also, AYA2017-89637-R and FEDER funds are acknowledged. We are thankful to the following observers who participated and provided data for respective events as listed in Table B.1: Orlando A. Naranjo from Universidad de Los Andes, Merida/VEN; Faustino Organero from La Hita Observatory - Toledo/ESP.

We report the lens mass and distance measurements of the nearby microlensing event TCP J05074264+2447555. We measure the microlens parallax vector ${\pi}_{\rm E}$ using Spitzer and ground-based light curves with constraints on the direction of lens-source relative proper motion derived from Very Large Telescope Interferometer (VLTI) GRAVITY observations. Combining this ${\pi}_{\rm E}$ determination with the angular Einstein radius $\theta_{\rm E}$ measured by VLTI GRAVITY observations, we find that the lens is a star with mass $M_{\rm L} = 0.495 \pm 0.063~M_{\odot}$ at a distance $D_{\rm L} = 429 \pm 21~{\rm pc}$. We find that the blended light basically all comes from the lens. The lens-source proper motion is $\mu_{\rm rel,hel} = 26.55 \pm 0.36~{\rm mas\,yr^{-1}}$, so with currently available adaptive-optics (AO) instruments, the lens and source can be resolved in 2021. This is the first microlensing event whose lens mass is unambiguously measured by interferometry + satellite parallax observations, which opens a new window for mass measurements of isolated objects such as stellar-mass black holes., Comment: 3 Figures and 6 Tables Submitted to AAS Journal

We report a luminous Type II supernova, ASASSN-15nx, with a peak luminosity of M_V=-20 mag, that is between typical core-collapse supernovae and super-luminous supernovae. The post-peak optical light curves show a long, linear decline with a steep slope of 2.5 mag/100 days (i.e., an exponential decline in flux), through the end of observations at phase ~260 days. In contrast, the light curves of hydrogen rich supernovae (SNe II-P/L) always show breaks in their light curves at phase ~100 days, before settling onto Co56 radioactive decay tails with a decline rate of about 1 mag/100 days. The spectra of ASASSN-15nx do not exhibit the narrow emission-line features characteristic of Type IIn SNe, which can have a wide variety of light-curve shapes usually attributed to strong interactions with a dense circumstellar medium (CSM). ASASSN-15nx has a number of spectroscopic peculiarities, including a relatively weak and triangularly-shaped H-alpha emission profile with no absorption component. The physical origin of these peculiarities is unclear, but the long and linear post-peak light curve without a break suggests a single dominant powering mechanism. Decay of a large amount of Ni56 (M_Ni56 = 1.6 +/- 0.2 M_sun) can power the light curve of ASASSN-15nx, and the steep light-curve slope requires substantial gamma-ray escape from the ejecta, which is possible given a low-mass hydrogen envelope for the progenitor. Another possibility is strong CSM interactions powering the light curve, but the CSM needs to be sculpted to produce the unique light-curve shape and to avoid producing SN IIn-like narrow emission lines., Accepted for publication in ApJ. Ancillary ASCII tables added: photsn.txt -- photometry; L.txt -- blackbody bolometric luminosity

We present optical photometry and spectroscopy of the Type II supernova ASASSN-14jb, together with VLT MUSE IFU observations of its host galaxy and a nebular-phase spectrum. This SN, in the nearby galaxy ESO 467-G051 ($z=0.006$), was discovered and followed-up by the All Sky Automated Survey for SuperNovae (ASAS-SN). We present LCOGTN $BVgri$ and $Swift$ $w2m1w1ubv$ optical and near-UV/optical light curves and several optical spectra in the early photospheric phase. ASASSN-14jb exploded $\sim 2$ kpc above the star-forming disk of ESO 467-G051, an edge-on disk galaxy. The large projected distance from the disk and non-detection of any H II region in a 1.4 kpc radius in projection are in conflict with the standard environment of core-collapse supernova progenitors and suggests the possible scenario that the progenitor received a kick in a binary interaction. Our analysis yields $D=25\pm 1$ Mpc, $M(^{56}Ni) = 0.0210 \pm 0.0025$ M$_\odot$, $E_{exp}\approx 0.25 \times 10^{51}$ ergs, $M_{ej}\approx 6$ M$_\odot$, and progenitor $R_* = 580 \pm 28$ R$_\odot$, which seems to be consistent with the sub-Solar metallicity of $0.3 \pm 0.1$ Z$_\odot$ derived from the SN spectrum. The nebular spectrum constrains $M_{prog} \simeq 10-12 $ M$_{\odot}$. We discuss the low oxygen abundance of the host galaxy derived from the MUSE data, $12+\log{(O/H)} = 8.27^{+0.16}_{-0.20}$ (O3N2 strong line method), and compare it with the supernova spectra, which is also consistent with a sub-Solar metallicity progenitor. We finally discuss the possible scenarios for the unusual environment for ASASSN-14jb and conclude that either the in-situ star formation or a runaway would imply a low mass progenitor, agreeing with our estimate from the supernova nebular spectrum. We show that the detailed study of the environment can agree with the stronger constrains of the transient observations. (abridged), Comment: 24 pages, submitted to A&A

BACKGROUND We hypothesize that oropharyngeal leak pressures differ between the LMA® Protector™ and the AuraGain™, two novel supraglottic airway devices offering the possibility of intubation. METHODS Ninety-eight male patients ASAI-II were randomly assigned to the AuraGainTM or ProtectorTM group. Oropharyngeal leak pressure was measured by incrementing cuff volume in 10 mL steps from 10 mL to 40 mL. The primary outcome was oropharyngeal leak pressure at 40 mL cuff volume. Secondary parameters such as transdevice intubation success, intubation time, the number of intubation attempts, and resistance during advancement of the endotracheal tube were determined. RESULTS Mean (SD) oropharyngeal leak pressures at cuff volume of 40 mL was 30.1 (6) cmH2O for the AuraGainTM and 28.2 (7) cmH2O for the LMA ProtectorTM (P=0.142). The mean intracuff pressure for the AuraGainTM was 154 (41) cmH2O and 200 (43) cmH2O for the LMA Protector (P≤0.001). The number of attempts to insert the laryngeal mask was higher for the AuraGainTM group (P=0.002). Intubation time was lower in the AuraGainTM group (15.7 s vs. 18.5 s [ProtectorTM group]; P=0.004), and less resistance in advancing the tracheal tube through the AuraGainTM compared to LMA ProtectorTM device (P

AuraGainTM, a novel third-generation laryngeal mask, can facilitate insertion of a gastric tube and provide the potential advantage of intubation. Data are lacking on intubation through the AuraGain laryngeal mask. Eighty-eight hip or knee surgery patients were enrolled in this parallel randomized-controlled trial. We hypothesized that intubation time using the AuraGain laryngeal mask would be no longer than that for standard flexible bronchoscopic intubation over a slit Guedel tube, with a non-inferiority margin of five seconds. The following data were recorded during a maximum of three intubation attempts: intubation time, number of intubation attempts, degree of resistance to advance the endotracheal tube, and mask placement (i.e., Brimacombe score). Follow-up outcomes, including neck pain, hoarseness, and dysphagia, were also measured two and 24 hr postoperatively. Patients and outcome assessors remained blinded until the last examination. Mean intubation time was similar between the Guedel tube and AuraGain groups (23.6 sec vs 21.4 sec, respectively). The upper limit of the 95% confidence interval (CI) of the difference in mean intubation time between groups fell below our pre-specified non-inferiority margin; therefore, we found the AuraGain laryngeal mask to be non-inferior to the slit Guedel tube (adjusted group difference, −1.6 sec; 95% CI, −3.7 to 0.5). Successful intubation was achieved in the majority of patients (≥ 95%) in each group on the first attempt. No resistance to insertion of the endotracheal tube was encountered in the majority of patients in each group, and no complications were reported during the 24-hr postoperative period. There was no difference in the Brimacombe score or in the status of postoperative morbidity between the two groups. We conclude that flexible bronchoscopic intubation through an AuraGain laryngeal mask can be achieved at least as fast as standard bronchoscopic intubation without contributing to additional patient morbidity or postoperative discomfort. www.clinicaltrials.gov , NCT 02570269. Registered 23 September 2015.

Background: There is controversy concerning use of laryngeal mask airway devices for procedures lasting more than 2 h. The LMA ProSealTM is a laryngeal mask device with a modified cuff to facilitate ventilation and a drain tube to provide airway protection that is better suited for prolonged use than the LMA ClassicTM. Objectives: We aimed to describe the successful use of the LMA ProSealTM in seven patients in a variety of clinical situations for procedures lasting more than 5 h and provide practical guidelines about its use in this situation. Results: The cases illustrate the use of the LMA ProSealTM in a variety of clinical situations (supine and prone position) and for a variety of prolonged procedures: as a planned airway device and as an airway rescue device. LMA ProSealTM forms an effective seal with the respiratory tract (10 cm H2O higher) and is therefore suited as ventilator device. It also forms an effective seal with the gastrointestinal tract (30 cm H2O higher), provides protection against aspiration and gastric insufflation and provides easy access to the gastrointestinal tract allowing the passage of a gastric tube reducing again the risk of aspiration. Conclusion: The use of the LMA ProSealTM for prolonged procedures is feasible. In principle, it should be safer and more effective than the LMA ClassicTM.

Summary We investigated the hypothesis that the oropharyngeal leak pressure would differ between the GuardianCPV™ and the LMA Supreme™ in anaesthetised patients. We randomly assigned 120 patients to receive either the GuardianCPV or the LMA Supreme for airway management. Oropharyngeal leak pressure was measured during cuff inflation from 0 to 40 ml in 10-ml steps. In addition, intracuff pressure, fibreoptic position of the airway and drain tube, device insertion success, ventilation success, blood staining and airway morbidity were determined. Mean (SD) oropharyngeal leak pressures for clinically acceptable cuff volumes of 20–40 ml were 31 (7) cmH2O for the GuardianCPV and 27 (7) cmH2O for the LMA Supreme (p

This manuscript presents information for all supernovae discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN) during 2015, its second full year of operations. The same information is presented for bright ($m_V\leq17$), spectroscopically confirmed supernovae discovered by other sources in 2015. As with the first ASAS-SN bright supernova catalog, we also present redshifts and near-UV through IR magnitudes for all supernova host galaxies in both samples. Combined with our previous catalog, this work comprises a complete catalog of 455 supernovae from multiple professional and amateur sources, allowing for population studies that were previously impossible. This is the second of a series of yearly papers on bright supernovae and their hosts from the ASAS-SN team., 16 pages, 6 figures, 4 tables. Submitted to MNRAS. Tables containing the catalog data presented in this submission are included in machine-readable format as ancillary files. Manuscript updated to reflect changes made in the published version and to correct an error in the host galaxy magnitudes presented in Tables 3 and 4. For a brief video explaining this paper, see https://youtu.be/iqYJp1AmyMw

Background The Laryngeal Mask Airway (LMA) ProSeal(TM) and the i-Gel(TM) are two extraglottic devices with either an inflatable cuff or a non-inflatable cuff. Aim We test the hypothesis that oropharyngeal leak pressure and fiberoptic position of the airway tube differ between the size 2 LMA ProSeal(TM) and the i-Gel(TM) in non-paralysed ventilated children. Methods Fifty-one children aged 1.5-6 years weighing 10-25 kg were studied using a crossover design. Anaesthesia was with remifentanil/propofol mixture. The LMA ProSeal(TM) and the i-Gel(TM) were inserted into each patient in random order. Results Oropharyngeal leak pressure for the LMA ProSeal(TM) and the i-Gel(TM) was similar at 22 (5) and 21 (5) cm H(2) O, respectively. Fiberoptic position of the airway tube for the LMA ProSeal(TM) and the i-Gel(TM) was similar, with the vocal cords visible from the distal airway tube in 94% and 96%, respectively. Conclusion We conclude that oropharyngeal leak pressure and fiberoptic position of the airway tube are similar for the size 2 LMA ProSeal(TM) and i-Gel(TM) in non-paralysed ventilated children.

The i-gel™ and LMA Supreme™ are extraglottic airway devices with non-inflatable and inflatable cuffs, respectively. We hypothesised that directly measured mucosal pressures would differ between these devices in anesthetised paralysed patients. Thirty patients were randomly allocated to receive one of these two devices. Four pressure sensors were attached to all airway devices used to measure mucosal pressure at the base of the tongue, the distal oropharynx, the hypopharynx and the pyriform fossa. At these four places, median (IQR [range]) i-gel mucosal pressures were 8.0 (2.7-10.7 [0-26.7]), 5.0 (2.7-7 [1.0-37.3]), 9.3 (2.7-13.3 [0-22.7] and 8.0 (2.7-10.7 [0-25.3]) cmH(2)O, respectively, and for the LMA Supreme, these were 5.0 (0.5-8.0 [0-33]), 4.0 (1.3-9.3 [0-24]), 10.7 (4-17.3 [0-26.7]) and 8.0 (0-10.7 [0-36]) cmH(2)O, respectively. Mucosal pressures were low and similar for both devices. The LMA Supreme mucosal pressures were higher in the hypopharynx than in the distal oropharynx (p = 0.04) and base of the tongue (p = 0.011). There were no pressure differences between the locations for the i-gel.

We present the discovery, photometric and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with tau_d=5 days, and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M_r=-17mag and has mean velocities of 10,000 km/s. Our light curve modeling suggests a radioactivity powered event and an ejecta mass of 0.16 Msun. If powered by Nickel, we show that the Nickel mass must be very small (0.02 Msun) and that the supernova quickly becomes optically thin to gamma-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of Aluminum or Helium is present. If Aluminum is present, we speculate that this may be an accretion induced collapse of an O-Ne-Mg white dwarf. If Helium is present, all observables of SN 2010X are consistent with being a thermonuclear Helium shell detonation on a white dwarf, a ".Ia" explosion. With the 1-day dynamic-cadence experiment on the Palomar Transient Factory, we expect to annually discover a few such events., Comment: 6 pages, 5 figures; Minor Changes; Note correction in Fig 4 caption; published by ApJL

In a randomised, non-crossover study, we tested the hypothesis that the ease of insertion using a duodenal tube guided insertion technique and the oropharyngeal leak pressure differ between the LMA ProSeal and the i-gel in non-paralysed, anesthetised female subjects. One hundred and fifty-two females aged 19-70 years were studied. Insertion success rate, insertion time and oropharyngeal leak pressure were measured. First attempt and overall insertion success were similar (LMA ProSeal, 75/76 (99%) and 76/76 (100%); i-gel 73/75 (97%) and 75 (100%), respectively). Mean (SD) insertion times were similar (LMA ProSeal, 40 (16) s; i-gel 43 (21) s). Mean oropharyngeal leak pressure was 7 cmH(2) O higher with the LMA ProSeal (p < 0.0001). Insertion of the LMA ProSeal and i-gel is similarly easy using a duodenal tube guided technique, but the LMA ProSeal forms a more effective seal for ventilation.

We investigated whether insertion of an LMA Supreme and its use for maintenance of anaesthesia is feasible in the prone position. Forty adult patients positioned themselves prone and were given propofol until the Bispectral Index was < 50. A size-4 LMA Supreme was inserted by experienced anaesthetists. Ease of insertion, ease of ventilation, efficacy of seal, ease of gastric tube insertion, blood staining, postoperative sore throat, and other complications were recorded. Insertion was successful at the first and second attempt in 37 (92.5%) and 3 (7.5%) patients, respectively. The mean (SD) insertion time was 21 (15) s. Oropharyngeal leak pressure was greater in females than males (29 (4) vs 25 (4) cmH(2)O, respectively, p = 0.01). Adequate ventilation was achieved in all patients. Gastric tube placement was successful in all patients. The frequency of blood staining and sore throat was 7.5% each. No other complications were noted. We conclude that use of the LMA Supreme in the prone position by experienced users is feasible.

The LMA Supreme is a new extraglottic airway device which brings together features of the LMA ProSeal, Fastrach and Unique. We test the hypothesis that ease of insertion, oropharyngeal leak pressure, fibreoptic position and ease of gastric tube placement differ between the LMA ProSeal and the LMA Supreme in paralysed anesthetised patients. Ninety-three females aged 19-71 years were studied. Both devices were inserted into each patient in random order. Two attempts were allowed. Digital insertion was used for the first attempt and guided insertion for the second attempt. Oropharyngeal leak pressure and fibreoptic position were determined during cuff inflation from 0 to 40 ml in 10 ml increments. Gastric tube insertion was attempted if there was no gas leak from the drain tube. First attempt and overall insertion success were similar (LMA ProSeal, 92% and 100%; LMA Supreme 95% and 100%). Guided insertion was always successful following failed digital insertion. Oropharyngeal leak pressure was 4-8 ml higher for the LMA ProSeal over the inflation range (p < 0.001). Intracuff pressure was 16-35 cm higher for the LMA ProSeal when the cuff volume was 20-40 ml (p < 0.001). There was an increase in oropharyngeal leak pressure with increasing cuff volume from 10 to 30 ml for both devices, but no change from 0 to 10 ml and 30-40 ml. There were no differences in the fibreoptic position of the airway or drain tube. The first attempt and overall insertion success for the gastric tube was similar (LMA ProSeal 91% and 100%; LMA Supreme 92% and 100%). We conclude that ease of insertion, gastric tube placement and fibreoptic position are similar for the LMA ProSeal and LMA Supreme in paralysed, anaesthetised females, but oropharyngeal leak pressure and intracuff pressure are higher for the LMA ProSeal.

BACKGROUND: We compared three techniques for insertion of the laryngeal mask airway ProSeal TM (PLMA) in patients with simulated difficult laryngoscopy using a rigid neck collar. METHODS: Ninety-nine anesthetized healthy female patients aged 19-68 yr were randomly allocated for PLMA insertion using the digital, introducer tool (IT) or guided techniques. Difficult laryngoscopy was simulated using a rigid neck collar. The laryngoscopic view was graded before PLMA insertion. The digital and IT techniques were performed according to the manufacturer's instructions. The guided technique involved priming the drain tube with an Eschmann tracheal tube introducer, placing the introducer in the esophagus under direct vision and railroading the PLMA into position. Failed insertion was defined by any of the following criteria: 1) failed pharyngeal placement, 2) malposition, and 3) ineffective ventilation. RESULTS: The median laryngoscopic view was 3 and the mean interincisor distance was 3.3 cm. Insertion was more frequently successful with the guided technique at the first attempt (guided 100%, digital 64%, IT 61%; P < 0.0001), but success after three attempts was similar (guided 100%, digital 94%, IT 91%). The time taken for successful placement was similar among groups at the first attempt, but was shorter for the guided technique after three attempts (guided 31 ± 8 s, digital 49 ± 28 s, IT 54 ± 37 s; P < 0.02). CONCLUSION: The guided insertion technique is more frequently successful than the digital or IT techniques in patients with simulated difficult laryngoscopy using a rigid neck collar.

The use of the classic laryngeal mask airway (classic LMA) in the prone position is controversial, but the ProSeal laryngeal mask airway (ProSeal LMA) maybe more suitable as it forms a better seal and provides access to the stomach. In the following retrospective audit, we describe our experience with the insertion of, and maintenance of anaesthesia with, the ProSeal LMA in 245 healthy adults in the prone position by experienced users. The technique involved (1) the patient adopting the prone position with the head to the side and the table tilted laterally; (2) preoxygenation to end-tidal oxygen >90%; (3) induction of anaesthesia with midazolam/alfentanil/propofol; (4) facemask ventilation (5) a single attempt at digital insertion and if unsuccessful a single attempt at laryngoscope-guided, gum elastic bougie-guided insertion; (6) gastric tube insertion; (7) maintenance of anaesthesia with sevoflurane/O2/N2O; (8) volume controlled ventilation at 8-12 ml/kg; (9) emergence from anaesthesia in the supine position; and (10) removal of the ProSeal LMA when awake. Facemask ventilation was always successful. ProSeal LMA insertion was successful in all patients: 237 with digital insertion and eight with bougie-guided insertion. Ventilation was successful in all patients. Gastric tube insertion was successful in all patients. Correctable partial airway obstruction occurred in three patients, but there was no hypoxia, hypercapnoea, displacement, regurgitation, gastric insufflation or airway reflex activation. Our findings suggest that the insertion of and maintenance of anaesthesia with the ProSeal LMA is feasible in the prone position by experienced users.

Study objective The study objective is to determine whether extraglottic airway devices (EADs) with or without mask aperture bars (MABs) result in similar anatomical positions in patients undergoing surgery. Design Prospective, randomized, crossover comparison of four extraglottic airway devices. Setting Operating theatre at a large teaching hospital. Patients Eighty consenting patients scheduled to undergo surgery with general anesthesia. Interventions Patients were randomly allocated to receive anesthesia with one of four tested EADs. Two versions of each EAD were inserted in random order; one with and one without MABs. Measurements and main results Endoscopic evaluation did not demonstrate any difference between the EADs with or without MABs. Contact between MABs and arytenoids (n=15) and herniation of arytenoids (n=7) was restricted to the Cobra-group patients. In nine patients the epiglottis made contact with a MAB, although this contact was very limited and often unilateral. Conclusion This study demonstrated that the anatomical position of the four tested single-use EADs is similar with or without mask aperture bars. We therefore question whether MABs have a protective role in prevention of airway occlusion and whether MABs are essential components. In the overall majority of EADs with MABs, the latter did not prevent contact with the epiglottis. Contact and herniation of the laryngeal structures are seen more frequently when more than two MABs are present.

We tested the hypothesis that, in patients with clear airways, the anatomical position of three single-use extraglottic airway devices is similar. The airways studied were: the laryngeal mask airway unique (LMA-U™), the Softseal laryngeal mask airway (SS-LM™) and the Cobra perilaryngeal airway (Cobra-PLA™). Three hundred spontaneously breathing patients were randomly allocated to have their airway managed using one of these three supraglottic airway devices. A rigid endoscope was passed down the airway tube and the following anatomical assessments were made: position of the epiglottis; position of the glottis; and position of the cuff. The epiglottis was more frequently visible with the LMA-U than with the SS-LM (76 vs 57%, p = 0.006) and with the LMA-U than with the Cobra-PLA (76 vs 46%, p < 0.0001). The epiglottis was in contact with the mask aperture bars in 25% of patients, and in 34% of these, the epiglottis was seen to be herniated through the aperture bars. Herniation of the epiglottis through the mask aperture bars occurred more frequently with the Cobra-PLA than the LMA-U (8 vs 3%, p = 0.008). The vocal cords and arytenoids were more frequently visible with the LMA-U and SS-LM than with the Cobra-PLA (both p < 0.006). Herniation of the arytenoids through the mask aperture bars was more frequently seen with the Cobra-PLA than with the LMA-U (8 vs 0%, p = 0.004). The position of the cuff was optimal for the LMA-U and SS-LM in 90% and 93% of patients, respectively. The cuff was more frequently in the midline with the LMA-U than with the SS-LM (p = 0.002). We conclude that the anatomical position of the LMA-U and SS-LMA is superior to that of the Cobra-PLA in patients with clear airways. The mask aperture bars probably have no anatomical utility and predispose to herniation of the pharyngeal structures.

Background The authors compared three disposable extraglottic airway devices in spontaneously breathing anesthetized adults: the LMA-Unique (LMA-U; The Laryngeal Mask Company, San Diego, CA), the Soft Seal laryngeal mask (SS-LM; Portex Ltd., Hythe, United Kingdom), and the Cobra perilaryngeal airway (Cobra-PLA; Engineered Medical Systems, Inc. Indianapolis, IN). Methods Three hundred twenty consecutive adults (American Society of Anesthesiologists physical status I-III; aged 18-80 yr) were randomly allocated for airway management with one of the three devices. Anesthesia was with fentanyl-propofol for induction and a sevoflurane-nitrous oxide-oxygen-fentanyl mixture for maintenance. Intraoperative data were collected by an unblinded observer about ease of insertion, effective airway time, oropharyngeal leak pressure, anatomical position (determined with a rigid endoscope), intracuff pressure changes, and airway trauma. Data were collected by a blinded observer about sore throat, dysphagia, and dysphonia 2 h after surgery. Results Insertion was easier with the LMA-U and SS-LM than with the Cobra-PLA (P < 0.02), but the overall failure rates were similar. Effective airway times were similar among groups. Oropharyngeal leak pressure was lower with the LMA-U than with the SS-LM and Cobra-PLA (P < 0.001). Intracuff pressure increased during surgery with all extraglottic airway devices. Anatomical position was better with the Cobra-PLA than with the SS-LMA (P < 0.001) and better with the SS-LM than with LMA-U (P < 0.001). Blood staining was detected more frequently with the Cobra-PLA than with the LMA-U and SS-LM (P < 0.001), but there were no differences in airway morbidity. Conclusion The LMA-U and SS-LM are easier to insert and cause less trauma than the Cobra-PLA, but the Cobra-PLA has a more effective seal than the LMA-U and better endoscopically determined anatomical position than the LMA-U and SS-LM.

We tested the hypothesis that digital insertion of the ProSeal laryngeal mask airway (ProSeal LMA) is more successful when using a suction catheter (SC) as a guide.Two hundred and forty-three patients (ASA physical status I-III; aged 18-84 yr) were randomly allocated for the digital or SC-guided technique. The digital technique was performed according to the manufacturer's instructions. The SC technique involved priming the drain tube with the SC so that it protruded by 15 cm, blindly inserting the SC into the pharynx to a depth of 15 cm, followed by the digital technique. Failed insertion was defined by any of the following criteria: 1) failed passage into the pharynx; 2) malposition; and 3) ineffective ventilation. Any airway trauma, and visible or occult blood was noted. Sore throat, dysphonia and dysphagia were assessed 16 to 24 hr postoperatively.Fewer insertion attempts were required with the SC-guided technique (P = 0.02), but first attempt and overall success were similar. The time taken to provide an effective airway was shorter for the SC-guided technique (36 +/- 24 sec vs 44 +/- 28 sec, P = 0.02). A lateral approach was required less frequently with the SC-guided technique (0% vs 4%, P = 0.0004). There were no adverse events. Mouth trauma was more frequent with the digital technique (P = 0.04), but overall trauma was similar. There were no differences in the frequency of visible or occult blood. There were no differences in postoperative airway morbidity.The SC-guided technique is more frequently successful than the digital technique and is associated with less mouth trauma during insertion of the ProSeal LMA. We suggest that the SC technique may be a useful alternative when the digital technique fails.

Background and objective: We tested the feasibility of using the intubating laryngeal mask airway Fastrach(TM) (ILMA) as a ventilatory device and for flexible lightwand-guided tracheal intubation for out-of-hospital cardiopulmonary resuscitation by an emergency physician. Methods: After completion of a training programme, a single experienced emergency physician used the technique for all patients requiring out-of-hospital tracheal intubation over a 10-month period. If access to the head and neck was limited, the intubating laryngeal mask airway was inserted from below and to the side, otherwise it was inserted from above the head. Data about the time for the ambulance to reach the patient, whether or not access to the head and neck was limited, whether or not circulation was successfully restored, and the insertion and intubation success rates were noted. Results: The mean (range) time for the ambulance to reach the patient was 12 (10-20) min. Access to the head and neck was limited in 8/37 (22%). Circulation was successfully restored in 10/37 (27%). The intubating laryngeal mask airway was successfully inserted at the first attempt in 35/37 (95%) and at the second attempt in 2/37 (5%). The tracheal tube was successfully inserted in 25/37 (67.5%) at the first attempt, 7/37 (19%) at the second attempt and 5/37 (13.5%) at the third attempt. There were no overall failures for intubating laryngeal mask airway insertion or tracheal intubation. There were no differences in success rate between positions. Oesophageal intubation was detected and corrected in 2/37 (5%). Conclusion: The intubating laryngeal mask airway has a high success rate as a ventilatory device and as a flexible lightwand-guided airway intubator during out-of-hospital cardiopulmonary resuscitation by a well-trained emergency physician. This technique may be particularly useful when there is limited access to the head and neck.

Background and objective: There are no data about the influence of anaesthetics on cardiovascular variables during pressure support ventilation of the lungs through the laryngeal mask airway. We compared propofol, sevoflurane and isoflurane for maintenance of anaesthesia with the ProSeal (R) laryngeal mask airway during pressure support ventilation. Methods: Sixty healthy adults undergoing peripheral musculo-skeletal surgery were randomized for maintenance with sevoflurane end-tidal 29%, isoflurane end-tidal 1.1% or propofol 6 mg kg(-1) h(-1) in oxygen 33% and air. Pressure support ventilation comprised positive end-expiratory pressure set at 5 cmH(2)O, and pressure support set 5 cmH(2)O above positive end-expiratory pressure. Pressure support was initiated when inspiration produced a 2 cmH(2)O reduction in airway pressure. A blinded observer recorded cardiorespiratory variables (heart rate, mean blood pressure, oxygen saturation, air-way occlusion pressure, respiratory rate, expired tidal volume, expired minute volume and end-tidal CO2), adverse events and emergence times. Results: Respiratory rate and minute volume were 10-21% lower, and end-tidal CO2 6-11% higher with the propofol group compared with the sevoflurane or isoflurane groups, but otherwise cardiorespiratory variables were similar among groups. No adverse events occurred in any group. Emergence times were longer with the propofol group compared with the sevoflurane or isoflurane groups (10 vs. 7 vs. 7 min). Conclusion: Lung ventilation is less effective and emergence times are longer with propofol than sevoflurane or isoflurane for maintenance of anaesthesia during pressure support ventilation with the ProSeal (R) laryngeal mask airway. However, these differences are small and of doubtful clinical importance.

The LMA-ProSeal laryngeal mask airway is a new laryngeal mask airway with a modified cuff and drainage tube. We compared oropharyngeal leak pressure, intracuff pressure and anatomical position (assessed fibreoptically) for the Size 5 LMA-ProSeal laryngeal mask airway and the classic laryngeal mask airway in different head-neck positions and using different intracuff inflation volumes.Thirty paralysed anaesthetized adult male patients were studied. The LMA-ProSeal laryngeal mask airway and the classic laryngeal mask airway were inserted into each patient in random order. The oropharyngeal leak pressure, intracuff pressure, and anatomical position of the airway tube and drainage tube (LMA-ProSeal laryngeal mask airway only) were documented in four head and neck positions (neutral first, then flexion, extension and rotation in random order), and at 0-40 mL cuff volumes in the neutral position in 10 mL increments.Compared with the neutral position, the oropharyngeal leak pressure for both the LMA-ProSeal laryngeal mask airway and the classic laryngeal mask airway was higher in flexion and rotation (all Por = 0.02), but lower in extension (all Por = 0.01). Changes in head-neck position did not alter the anatomical position of the airway tube or the drainage tube. The oropharyngeal leak pressure was always higher for the LMA-ProSeal laryngeal mask airway (all Por = 0.005) and anatomical position better for the classic laryngeal mask airway (all Por = 0.04).The anatomical position of the LMA-ProSeal and the classic laryngeal mask airway is stable in different head-neck positions, but head-neck flexion and rotation are associated with an increase, and head-neck extension a decrease, in oropharyngeal leak pressure and intracuff pressure. The Size 5 LMA-ProSeal laryngeal mask airway is capable of forming a more effective seal than the Size 5 classic laryngeal mask airway in males.

Background: The ProSealTM (PLMA) is a new laryngeal mask device with a modified cuff to improve the seal and a drain tube to provide access to the gastrointestinal tract. We assessed the performance of the size 2 (which has no dorsal cuff) and size 3 (which has a dorsal cuff) in terms of insertion success, efficacy of seal, tidal volume, gas exchange, fiberoptic position, gastric tube placement and frequency of problems. Methods: Eighty children undergoing minor surgery were studied (n = 40, size 2 PLMA, weight 10–25 kg; n = 40, size 3 PLMA, weight >25–50 kg). Induction was with remifentanil and propofol. Insertion was with the introducer tool and by experienced users. Maintenance was with propofol or sevoflurane and pressure controlled ventilation. Results: The first-time and overall insertion success rate was 84 and 100%, respectively. Oropharyngeal leak pressure was 31 ± 5 cmH2O. There were no gastric or drain tube air leaks. Tidal volume and gas exchange was adequate in all patients, other than two brief episodes of hypoxia because of airway reflex activation. The vocal cords and epiglottis were visible in 99 and 80%, respectively, via the airway tube. The first-time and overall insertion success rate for gastric tube insertion was 87 and 100%, respectively. During maintenance, the PLMA was removed in one patient with airway reflex activation and another required epinephrine for bronchospasm. There were no differences in performance between the sizes 2 and 3 PLMA. Conclusion: The PLMA is an effective airway device in children and isolates the glottis from the esophagus when correctly positioned. Despite the lack of a dorsal cuff, the performance of the size 2 was similar to the size 3 PLMA in the age groups tested.

We tested the hypothesis that the life-span of the ProSeal laryngeal mask airway (LMA) is shorter than the Classic LMA. We also compared residual cuff volumes and changes in elastance and permeability with use. Six new size 4 ProSeal LMAs and 6 new size 4 Classic LMAs were tested. Each LMA underwent a simulated clinical use cycle until it failed the pre-use check tests. The simulated clinical use cycle comprised: i) inflating the cuff to the maximum recommended volume for 1 h; ii) immersion in an enzymatic solution for 3 min; iii) washing the external and internal surfaces; iv) automatic washing for 14 min (< or =85 degrees C); v) drying for 30 min (< or =75 degrees C); and vi) autoclaving at 134 degrees C for 4 min at 206 kPa. Before the first cycle and every 10 subsequent cycles, the cuff was inflated with 40 mL air and the intracuff pressure was measured immediately and 3 h later. The initial intracuff pressure was taken to be an inverse measure of the elastance or resistance to deformation, and the intracuff pressure change were taken as a measure of the permeability. The residual cuff volume was determined for 10 Classic and 10 ProSeal size 4 LMAs using a gas dilution technique. The mean +/- sd (range) longevity for the ProSeal LMA and Classic LMA was 82 +/- 23 (45-109) uses and 133 +/- 35 (76-176) uses, respectively. The ProSeal LMA has a shorter life-span than the Classic LMA (P = 0.01). For the ProSeal LMA, there was no change in elastance or permeability with use. For the Classic LMA, there was a decrease in elastance (P < 0.0001) and an increase in permeability (P < 0.0001) with use. The residual cuff volume was higher for the ProSeal LMA (2.6 +/- 1.3 mL versus 1.5 +/- 0.9, P = 0.04). We conclude that the life-span of the ProSeal LMA is shorter than the Classic LMA, but both exceed the manufacturer's recommendations of 40 uses. We recommend that reusable LMA devices be discarded when they fail the pre-use check tests, rather than after a specific number of uses.

We compared positive pressure ventilation with pressure support ventilation at different levels of positive end expiratory pressure (PEEP) using the ProSeal laryngeal mask airway (PLMA). Forty-two anaesthetized adults (ASA 1-2, aged 19 to 63 years) underwent positive pressure ventilation and then pressure support ventilation each with PEEP set at 0, 5 and 10 cmH2O in random order. Pressure support ventilation was with the inspired tidal volume (VTInsp) set at 7 ml/kg and the respiratory rate adjusted to maintain the end-tidal CO2 (ETCO2) at 40 mmHg. Pressure support ventilation was with pressure support set at 5 cmH2O above PEEP and initiated when inspiration produced a 2 cmH2O reduction in airway pressure. Tidal volumes were similar during positive pressure and pressure support ventilation with PEEP, but were higher for the former without PEEP. Respiratory rate and peak inspiratory flow rate were higher during pressure support than positive pressure ventilation (all P2O, ETCO2 was lower for pressure support than positive pressure ventilation. During positive pressure ventilation, there was an increase in Ppaw, Mpaw and dynamic compliance (Cdyn) with increasing levels of PEEP (all P2, work of breathing, and expired airway resistance with increasing levels of PEEP (all P2, non-invasive mean arterial pressure, heart rate or leak fraction. We conclude that pressure support ventilation provides equally effective gas exchange as positive pressure ventilation during PLMA anaesthesia with or without PEEP at the tested settings. During pressure support, PEEP increases ventilation and reduces work on breathing without increasing leak fraction.

We tested the hypothesis that ease of insertion, oropharyngeal leak pressure, fiberoptic position, ease of ventilation, and mucosal trauma are different for the Soft Seal laryngeal mask airway (SSLM) and the laryngeal mask airway Unique (LMA-U). Ninety paralyzed, anesthetized adult patients (ASA I-II; 18-80 yr old) were studied. Both devices were inserted into each patient in random order. Oropharyngeal leak pressure and fiberoptic position were determined during cuff inflation from 0-40 mL in 10-mL increments and at an intracuff pressure of 60 cm H(2)O. Ease of ventilation was determined by controlling ventilation for 10 min at 8 and 12-mL/kg tidal volume and recording hemoglobin oxygen saturation, end-tidal CO(2), leak fraction, peak airway pressure, and the presence or absence of gastric insufflation. Mucosal trauma was determined by examining the first randomized device for the presence of visible and occult blood. Insertion time was shorter (P = 0.0001) and fewer attempts were required (P = 0.005) for the LMA-U. There were no failed uses of either device. Oropharyngeal leak pressures were similar, but fiberoptic position was superior with the LMA-U (Por = 0.0003). There were no differences in hemoglobin oxygen saturation, end-tidal CO(2), leak fraction, or peak airway pressure at either tidal volume. Gastric insufflation was not detected in either group at either tidal volume. The frequency of visible (P = 0.009) and occult blood (P = 0.0001) was less with the LMA-U. We conclude that the LMA-U is superior to the SSLM in terms of ease of insertion, fiberoptic position, and mucosal trauma, but similar in terms of oropharyngeal leak pressure and ease of ventilation.

We compare the Soft Seal and Unique single-use, plastic laryngeal mask airway devices with respect to intracuff pressure, directly measured mucosal pressure and in vitro elastance. Ten fresh male cadavers were studied. Microchip pressure sensors were attached to the following locations: A) the anterior middle part of the cuff side; B) the posterior tip of the cuff; C) the anterior base of the cuff; D) the posterior middle part of the cuff side; E) the backplate; and F) the posterior tube. The size 5 Unique and size 5 Soft Seal were inserted in random order using laryngoscope-guidance. Intracuff pressure and mucosal pressure were documented at 0 to 40 mL cuff volume in 10 mL increments. In vitro elastance was determined between 20 to 40 mL cuff volume. For both devices, mucosal pressure increased with cuff volume at most locations. Intracuff pressures and in vitro elastance (5.2 +/- 0.7 cm H(2)O/mL vs 3.8 +/- 0.4 cm H(2)O/mL, P

Background The authors compared the manufacturer's weight-based formula (size 3 for weight < 50 kg, size 4 for weight 50-70 kg, and size 5 for weight > 70 kg) with a sex-based formula (size 4 for women and size 5 for men) for selecting the appropriate size of ProSeal laryngeal mask airway. Methods Two hundred thirty-seven healthy, anesthetized, paralyzed adult patients (American Society of Anesthesiologists physical status I or II; age, 18-80 yr) were randomly allocated for weight- or sex-based size selection. An experienced user inserted the ProSeal laryngeal mask airway with the digital technique. The following were compared: ease of insertion, oropharyngeal leak pressure, ease of ventilation, gas exchange, location of gas leak, anatomic position, mucosal injury, and postoperative pharyngolaryngeal problems. Intraoperative and postoperative data collection were unblinded and blinded, respectively. Results Ease of insertion, anatomic position, gas exchange, mucosal injury, and postoperative pharyngolaryngeal problems were similar between groups. For the sex-based group, larger ProSeal laryngeal mask airways were selected more frequently (P < 0.0001), oropharyngeal leak pressure (P = 0.02) was higher, leak volume (P = 0.004) and leak fraction (P = 0.007) were lower, and oropharyngeal leaks (P = 0.03) were detected less frequently. Conclusion Size selection for the ProSeal laryngeal mask airway is equally effective using the manufacturer's weight-based formula or the sex-based formula in healthy, anesthetized, paralyzed adult patients, but leakage of small volumes of air from the mouth occurs less frequently with the sex-based formula.

The risk of prion protein cross-infection has focussed attention on the potential hazards of protein contamination of re-usable medical devices. This study determined the frequency of protein contamination of ProSeal™ laryngeal mask airways (PLMA) after two cleaning procedures and tested the hypothesis that the combination of hand- and machine-washing removes protein contamination more effectively than hand-washing alone. After clinical use fifty-four PLMAs were randomly allocated to be washed by hand or by hand then machine. All PLMAs were then autoclaved at 134°C for 4 minutes. After processing, each PLMA was immersed in a 1.2% solution of erythrosin B and examined for uptake of stain. The site (outer surface, bowl and edges of the cuff, airway and drain tube, finger strap) and severity (nil/mild/moderate/severe) of staining was scored by a blinded observer. There were no differences in the site or severity of staining between the two cleaning procedures. Staining was detected on 89% of PLMAs that were hand-washed and 78% of PLMAs that were hand-, then machine-washed (P=0.27). When staining occurred, it was mild in 98%, moderate in 2% and was never severe. Staining was more frequent on the edge than at any other location (all comparisons: P≤0.01). The strap never had any staining. We conclude that residual contamination of PLMAs with protein deposits is common even when machine-washing is used to augment hand-washing before autoclaving. The infection risk associated with these deposits remains to be determined.

UNLABELLED The ProSeal laryngeal mask airway (ProSeal LMA) provides a better seal and probably better airway protection than the classic laryngeal mask airway (classic LMA). We report the use of the ProSeal LMA in a 26-yr-old female with HELLP syndrome for failed obstetric intubation and postoperative respiratory support. Both laryngoscope-guided tracheal intubation and face mask ventilation failed, but a size 4 ProSeal LMA was easily inserted and high tidal volumes obtained. A gastric tube was inserted through the ProSeal LMA drain tube and 300 mL of clear fluid was removed from the stomach. There were no hemodynamic changes during ProSeal LMA insertion. Postoperatively, the patient was transferred to the intensive care unit, where she was ventilated via the ProSeal LMA for 8 h until the platelet count had increased and she was hemodynamically stable. Weaning and ProSeal LMA removal were uneventful. There is anecdotal evidence supporting the use of the LMA devices for failed obstetric intubation (19 cases) and for postoperative respiratory support (8 cases). In principle, the ProSeal LMA may offer some advantages over the classic LMA in both these situations. IMPLICATIONS We report the successful use of the ProSeal laryngeal mask airway for failed obstetric intubation and postoperative respiratory support in a patient with HELLP syndrome.

Background The authors compare three techniques for insertion of the ProSeal laryngeal mask airway. Methods Two hundred forty healthy patients aged 18-80 yr were randomly allocated for ProSeal laryngeal mask airway insertion using the digital, introducer tool (IT), or gum elastic bougie (GEB)-guided techniques. The digital and IT techniques were performed according to the manufacturer's instructions. The GEB-guided technique involved priming the drain tube with the GEB, placing the GEB in the esophagus under direct vision, and inserting the ProSeal laryngeal mask airway using the digital technique with the GEB as a guide. Failed insertion was defined by any of the following criteria: (1) failed pharyngeal placement; (2) malposition (air leaks, negative tap test results, or failed gastric tube insertion if pharyngeal placement was successful); and (3) ineffective ventilation (maximum expired tidal volume < 8 ml/kg or end-tidal carbon dioxide > 45 mmHg if correctly positioned). Any visible or occult blood was noted. Sore throat, dysphonia, and dysphagia were assessed 18-24 h postoperatively. Results Insertion was more frequently successful with the GEB-guided technique at the first attempt (GEB, 100%; digital, 88%; IT, 84%; both P < 0.001), but success after three attempts was similar (GEB, 100%; digital, 99%; IT, 98%). The time taken to successful placement was similar among groups at the first attempt but was shorter for the GEB-technique after three attempts (GEB, 25 +/- 14 s; digital, 33 +/- 19 s; IT, 37 +/- 25 s; both: P < 0.003). There were no differences in the frequency of visible blood, but occult blood occurred less frequently with the GEB-guided technique (GEB, 12%; digital, 29%; IT, 31%; both: P < 0.02) but was similar among techniques if insertion was successful at the first attempt. There were no differences in postoperative airway morbidity. CONCLUSION The GEB-guided insertion technique is more frequently successful than the digital or IT techniques. The authors suggest that the GEB-guided technique may be a useful backup technique for when the digital and IT techniques fail.

We tested the hypothesis that mucosal pressures are higher for the laryngeal tube airway trade mark than the ProSeal laryngeal mask airway. Fifteen fresh cadavers were studied. Microchip pressure sensors were attached to the laryngeal tube airway and ProSeal laryngeal mask airway at four similar anatomical locations (base of tongue, lateral pharynx, posterior pharynx and posterior hypopharynx) and three dissimilar locations (laryngeal tube airway trade mark, anterior and lateral hypopharynx; ProSeal laryngeal mask airway, pyriform fossa). The cuff volume (laryngeal tube airway, < or = 140 ml; ProSeal laryngeal mask airway, < or = 30 ml) was adjusted until the oropharyngeal leak pressure was 15 cm H2O and the mucosal pressures recorded. This was repeated at an oropharyngeal leak pressure of 20, 25 and 30 cm H2O. Mucosal pressures in the lateral pharynx were always similar. Mucosal pressures at the base of tongue and posterior pharynx were similar for the laryngeal tube airway and ProSeal laryngeal mask airway at 15 and 20 cm H2O, but were higher for the laryngeal tube airway at 25 cm H2O at 30 cm H2O. Mucosal pressures in the posterior hypopharynx were always higher for the laryngeal tube airway (all: p < 0.03). Mean mucosal pressures for the laryngeal tube airway ranged from 8-31, 2-13 and 15-41 cm H2O for the base of tongue, lateral pharynx and posterior pharynx (proximal cuff) respectively and 3-7, 3-7 and 7-18 cm H2O for the anterior, lateral and posterior hypopharynx (distal cuff) respectively. Mean mucosal pressures for the ProSeal laryngeal mask airway ranged from 6-23, 3-10, 8-25, 6-17 and 2-8 cm H2O for the base of tongue, lateral pharynx, posterior pharynx, pyriform fossa and posterior hypopharynx respectively. We conclude that mucosal pressures are higher for the laryngeal tube airway, particularly when oropharyngeal leak pressure greater than 25 cm H2O. This suggests that mucosal ischemic injury will be more common with the LTA than the PLMA.

Background The ProSeal laryngeal mask airway (PLMA) is a new laryngeal mask device with a modified cuff to improve seal and a drainage tube to provide a channel for regurgitated fluid and gastric tube placement. In the present randomized, crossover study, the authors tested the hypothesis that ease of insertion, airway sealing pressure, and fiberoptic position differ between the PLMA and the standard laryngeal mask airway (LMA). For the PLMA, we also assess ease of gastric tube placement and the efficacy of an introducer tool. Methods Sixty paralyzed, anesthetized adult patients were studied. Both devices (only size 4) were inserted into each patient in random order. Airway sealing pressure and fiberoptic position were determined during cuff inflation from 0 to 40 ml in 10-ml increments. Gastric tube insertion was attempted with the PLMA if there was no gas leak from the drainage tube. In 60 additional patients, ease of insertion for the PLMA was compared with and without an introducer. Results First-time success rates were higher (60 of 60 vs. 52 of 60; P = 0.003) and the effective airway time shorter (9 +/- 3 s vs20 +/- 18 s; P < 0.0001) for the LMA. There were no failed uses of either device within three attempts. Airway sealing pressure was 8-11 cm H2O higher for the PLMA at all cuff volumes (P < 0.00001) and was higher in females for both devices. Fiberoptic position was better with the LMA at all cuff volumes (P < 0.00001), but vocal cord visibility was similar (LMA, 59 of 60; PLMA, 56 of 60). For the PLMA, gastric tube placement was successful in 58 of 58 patients and took 9 +/- 5 s. First-time success rates were higher (59 of 60 vs53/60; P = 0.03) and the effective airway time shorter (15 +/- 13 s vs 23 +/- 18 s; P = 0.008) with the introducer. Conclusion The PLMA is capable of achieving a more effective seal than the LMA and facilitates gastric tube placement, but it is more difficult to insert unless an introducer tool is used. When correctly positioned, the PLMA isolates the glottis from the upper esophagus with possible implications for airway protection.

The laryngeal tube airway (LTA) is a new extraglottic airway device with a large proximal cuff that inflates in the laryngopharynx and a distal conical cuff that inflates in the hypopharynx. We determine the influence of the cuff volume and anatomic location on pharyngeal mucosal pressures for the LTA.Fifteen fresh cadavers were studied. Microchip sensors were attached to the (anatomic location) anterior, lateral and posterior surface of the distal cuff (hypopharynx) and proximal cuff (laryngopharynx) of the size 4 LTA. Oropharyngeal leak pressure (OLP) and mucosal pressures were measured at 0-140 mL cuff volume in 20-mL increments. In addition, mucosal pressures for the proximal cuff were measured in three awake, topicalized volunteers.OLP and mucosal pressure at all locations increased with cuff volume (all: P0.01). Mucosal pressures were highest posteriorly. Mucosal pressures only exceeded 35 cm H(2)O (pharyngeal mucosal perfusion pressure) in the anterior and posterior laryngopharynx and when the cuff volume was80-100 mL. Mucosal pressures were similar for cadavers and awake volunteers.Mucosal pressures for the LTA increase with cuff volume, are highest posteriorly and potentially exceed mucosal perfusion pressure when cuff volume exceeds 80-100 mL.

We determined the success rates, cardiovascular responses and airway morbidity for gum-elastic bougie-guided insertion of the ProSeal™ laryngeal mask airway. One hundred anaesthetized, non-paralyzed adults (ASA 1–2, aged 18 to 80 years) were studied. The ProSeal LMA drainage tube was primed with a well-lubricated 16 French gauge gum-elastic bougie with the curved end proximal and the straight end protruding 30 cm beyond the drainage tube tip. The straight end of the gum-elastic bougie was inserted into the oesophagus under laryngoscopic guidance, the laryngoscope removed and the ProSeal LMA inserted using the standard insertion technique and the gum-elastic bougie as a guide. The following variables were recorded: ease of insertion, oropharyngeal leak pressure, ventilatory capability, ease of gastric tube insertion, blood staining on the bougie or LMA at removal, and postoperative airway morbidity. Haemodynamic data were recorded immediately pre-insertion and every minute for five minutes after insertion. Gum-elastic bougie and ProSeal LMA insertion was successful at the first attempt in all patients within 50 seconds. There were no significant increases in heart rate or blood pressure. Oropharyngeal leak pressure was 33 (17–40) cmH 2 O and ventilation was possible without leak in all patients at 9.5 ml.kg –1 tidal volume. There were no drainage tube or gastric air leaks. Gastric tube insertion was successful at the first attempt in all patients. Blood staining at removal was not detected on the gum-elastic bougie, but was detected in 3% of ProSeal LMAs. The incidence of sore throat, dysphagia and dysarthria was 21%, 9% and 1% respectively. We conclude that gum-elastic bougie-guided insertion of the ProSeal LMA has a high success rate and is associated with minimal haemodynamic change and a low incidence of trauma.

We compared the laryngeal mask airway ProSeal (PLMA) and the laryngeal tube airway (LTA), two new extraglottic airway devices, with respect to: 1) insertion success rates and times, 2) efficacy of seal, 3) ventilatory variables during pressure-controlled ventilation, 4) tidal volume in different head/neck positions, and 5) airway interventional requirements. One-hundred-twenty paralyzed anesthetized ASA physical status I and II adult patients were randomly allocated to the PLMA or LTA for airway management. A standardized anesthesia protocol was followed by two anesthesiologists experienced with both devices. The criteria for an effective airway included a minimal expired tidal volume of 6 mL/kg during pressure-controlled ventilation at 17 cm H(2)O with no oropharyngeal leak or gastric insufflation. First attempt success rates at achieving an effective airway were similar (PLMA: 85%; LTA: 87%), but after 3 attempts, success was more frequent for the PLMA (100% versus 92%, P = 0.02). Effective airway time was similar. Oropharyngeal leak pressure was larger for PLMA at 50% maximal recommended cuff volume (29 +/- 7 versus 21 +/- 6 cm H(2)O, P0.0001), but was similar at the maximal recommended cuff volume (33 +/- 7 versus 31 +/- 8 cm H(2)O). Tidal volumes (614 +/- 173 versus 456 +/- 207 mL, P0.0001) were larger and ETCO(2) (33 +/- 9 versus 40 +/- 11 mm Hg, P = 0.0001) lower for the PLMA. The number of airway interventions was significantly less frequent for the PLMA. Airway obstruction was more common with the LTA. When comparing mean tidal volumes in different head/neck positions, the quality of airway was unchanged in 56 of 60 patients (93%) with the PLMA and 42 of 55 (76%) with the LTA (P = 0.01). The PLMA offers advantages over the LTA in most technical aspects of airway management in paralyzed patients undergoing pressure-controlled ventilation.The laryngeal mask airway ProSeal offers advantages over the laryngeal tube airway in most technical aspects of airway management in paralyzed patients undergoing pressure-controlled ventilation.

The choice of airway device for resuscitation depends on the skill of the user, the equipment available, the conscious state of the patient, the location of the patient and the probable cause of the cardiorespiratory arrest. Extraglottic airway devices are recommended by the European and American Resuscitation Councils for use when intubation skills are lacking. In this review, we discuss recent research relevant to the use of extraglottic airway devices in resuscitation.

Twenty children aged 2-66 months were randomly allocated for airway management with either the laryngeal mask airway or uncuffed tracheal tube using intermittent positive pressure ventilation with a tidal volume of 8 ml.kg-1 and a respiratory rate adjusted to maintain end-expiratory carbon dioxide concentration at 5.3 kPa. Induction was with fentanyl/propofol and maintenance was with sevoflurane 2.5% in oxygen/air. The airway device was removed when the patients were awake and the patients were transferred to the postanaesthesia care unit 10 min later. Air was sampled from a point 1.5 m above the floor at a location remote from the ventilation outlet and analysed using a proton-transfer-reaction mass spectrometer capable of continuous trace gas analysis at the parts per billion volume (ppbv) level. The concentration of sevoflurane was recorded every minute during three consecutive phases: for 5 min before the introduction of sevoflurane (background); after introduction of sevoflurane until removal of the airway device (intra-operative); and every minute after removal until the concentration returned to background levels. Median (interquartile range [range]) intra-operative sevoflurane concentrations were 200-400 times higher than background values for the laryngeal mask airway 1 (1-2 [0-3]) ppbv vs. 404 (278-523 [83-983]) ppbv, respectively, and the tracheal tube 2 (1-3 [0-5]) ppbv vs. 396 (204-589 [107-1735]) ppbv (both p < 0.0001), and returned to background values within 5 min of removal. There were no differences in sevoflurane concentration between devices intra-operatively or after removal. The performance of the proton-transfer-reaction mass spectrometer was identical at the start and end of the 30-day study. We conclude that peri-operative sevoflurane concentration in a modern operating theatre is similar for the laryngeal mask airway and the uncuffed tracheal tube in paediatric patients receiving intermittent positive pressure ventilation. Intra-operative sevoflurane concentrations are five times lower than occupational safety limit requirements, and 1000 times lower 5 min after removal of the airway device with the patient awake. The proton-transfer-reaction mass spectrometer has potential for monitoring air quality in the operating theatre.

We tested the hypothesis that the ProSeal laryngeal mask airway (PLMA) is a more effective ventilatory device than the Classic laryngeal mask airway (LMA) for laparoscopic cholecystectomy.Eighty anaesthetized, paralyzed patients (ASA 1-2, aged 18-80 yr) were randomly allocated for airway management with the PLMA or LMA. Ease of insertion and efficacy of seal were determined. Peak airway pressures were recorded immediately before and after carboperitoneum to 2.0 kPa. The inspired oxygen concentration and/or the ventilatory variable were adjusted according to a protocol to maintain SpO2or = 95% and E'CO26.0 kPa. Oxygenation was considered suboptimal if SpO2 fell to 94-90% and failed if SpO2 was90%. Ventilation was considered suboptimal if E'CO2 was6.0-7.3 kPa and failed if E'CO2 was7.3 kPa.First-time insertion success rates were higher for the LMA (40/40 vs 33/40; P = 0.02). Seven patients required two attempts with the PLMA. Oropharyngeal leak pressure was higher for the PLMA [29 (SD 6) vs 19 (4) cm H2O; P0.001]. There was a similar, significant increase in peak airway pressure after carboperitoneum for both devices (P0.001). Before carboperitoneum, oxygenation and ventilation were optimal in all patients in both groups. After carboperitoneum, oxygenation was optimal in all patients in both groups, but ventilation was suboptimal more frequently with the LMA (8 vs 0; P = 0.01). In three of these eight patients, ventilation failed but was subsequently optimal with the PLMA.The PLMA is a more effective ventilatory device for laparoscopic cholecystectomy than the LMA. We do not recommend the use of the LMA for laparoscopic cholecystectomy.

ASASSN-14ae is a candidate tidal disruption event (TDE) found at the center of SDSS J110840.11+340552.2 ($d\simeq200$~Mpc) by the All-Sky Automated Survey for Supernovae (ASAS-SN). We present ground-based and Swift follow-up photometric and spectroscopic observations of the source, finding that the transient had a peak luminosity of $L\simeq8\times10^{43}$~erg~s$^{-1}$ and a total integrated energy of $E\simeq1.7\times10^{50}$ ergs radiated over the $\sim5$ months of observations presented. The blackbody temperature of the transient remains roughly constant at $T\sim20,000$~K while the luminosity declines by nearly 1.5 orders of magnitude during this time, a drop that is most consistent with an exponential, $L\propto e^{-t/t_0}$ with $t_0\simeq39$~days. The source has broad Balmer lines in emission at all epochs as well as a broad He II feature emerging in later epochs. We compare the color and spectral evolution to both supernovae and normal AGN to show that {\name} does not resemble either type of object and conclude that a TDE is the most likely explanation for our observations. At $z=0.0436$, ASASSN-14ae is the lowest-redshift TDE candidate discovered at optical/UV wavelengths to date, and we estimate that ASAS-SN may discover $0.1 - 3$ of these events every year in the future., 19 pages, 13 figures, 4 tables. Updated September 2014 to reflect changes in the final version published in MNRAS and to add significant amounts of additional data. Photometric data presented in this submission are included as ancillary files. For a brief video explaining this paper, see http://youtu.be/ahDuOt_eKgg