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Purpose: Oral chlorhexidine is used widely for mechanically ventilated patients to prevent pneumonia, but recent studies show an association with excess mortality. We examined whether de-adoption of chlorhexidine and parallel implementation of a standardized oral care bundle reduces intensive care unit (ICU) mortality in mechanically ventilated patients. Methods: A stepped wedge cluster-randomized controlled trial with concurrent process evaluation in 6 ICUs in Toronto, Canada. Clusters were randomized to de-adopt chlorhexidine and implement a standardized oral care bundle at 2-month intervals. The primary outcome was ICU mortality. Secondary outcomes were time to infection-related ventilator-associated complications (IVACs), oral procedural pain and oral health dysfunction. An exploratory post hoc analysis examined time to extubation in survivors. Results: A total of 3260 patients were enrolled; 1560 control, 1700 intervention. ICU mortality for the intervention and control periods were 399 (23.5%) and 330 (21.2%), respectively (adjusted odds ratio [aOR], 1.13; 95% confidence interval [CI] 0.82 to 1.54; P = 0.46). Time to IVACs (adjusted hazard ratio [aHR], 1.06; 95% CI 0.44 to 2.57; P = 0.90), time to extubation (aHR 1.03; 95% CI 0.85 to 1.23; P = 0.79) (survivors) and oral procedural pain (aOR, 0.62; 95% CI 0.34 to 1.10; P = 0.10) were similar between control and intervention periods. However, oral health dysfunction scores (− 0.96; 95% CI − 1.75 to − 0.17; P = 0.02) improved in the intervention period. Conclusion: Among mechanically ventilated ICU patients, no benefit was observed for de-adoption of chlorhexidine and implementation of an oral care bundle on ICU mortality, IVACs, oral procedural pain, or time to extubation. The intervention may improve oral health. [ABSTRACT FROM AUTHOR]

Purpose: Coronavirus disease 2019 (COVID-19) has placed a great burden on critical care services worldwide. Data regarding critically ill COVID-19 patients and their demand of critical care services outside of initial COVID-19 epicenters are lacking. This study described clinical characteristics and outcomes of critically ill COVID-19 patients and the capacity of a COVID-19-dedicated intensive care unit (ICU) in Kobe, Japan. Methods: This retrospective observational study included critically ill COVID-19 patients admitted to a 14-bed COVID-19-dedicated ICU in Kobe between March 3, 2020 and June 21, 2020. Clinical and daily ICU occupancy data were obtained from electrical medical records. The last follow-up day was June 28, 2020. Results: Of 32 patients included, the median hospital follow-up period was 27 (interquartile range 19–50) days. The median age was 68 (57–76) years; 23 (72%) were men and 25 (78%) had at least one comorbidity. Nineteen (59%) patients received invasive mechanical ventilation for a median duration of 14 (8–27) days. Until all patients were discharged from the ICU on June 5, 2020, the median daily ICU occupancy was 50% (36–71%). As of June 28, 2020, six (19%) died during hospitalization. Of 26 (81%) survivors, 23 (72%) were discharged from the hospital and three (9%) remained in the hospital. Conclusion: During the first months of the outbreak in Kobe, most critically ill patients were men aged ≥ 60 years with at least one comorbidity and on mechanical ventilation; the ICU capacity was not strained, and the case-fatality rate was 19%. [ABSTRACT FROM AUTHOR]

Although the Berlin definition of the acute respiratory distress syndrome (ARDS) is generally recognized, the differentiation from other diseases with severe gas exchange disturbances is often difficult in clinical practice. In particular, the assessment of radiological findings and identification of primary noncardiogenic lung edema pose problems. In ARDS typical inflammatory processes can be found with involvement of activated neutrophilic granulocytes. Anti-inflammatory treatment strategies were unsuccessful. Lung protective ventilation strategies and prone positioning are the only evidence-based treatment options. Identifying ARDS phenotypes according to the etiology or disease progression can possibly provide a targeted individualized treatment option. The control of various biomarkers for assessment and treatment is the main focus of scientific interest. The results of appropriate studies remain to be seen. [ABSTRACT FROM AUTHOR]

Capnography as the graphical representation of the expiratory carbon dioxide (CO2) concentration, is an essential component of monitoring of every ventilated patient, in addition to pulse oximetry. Capnography demonstrates the kinetics of CO2 in a noninvasive way and in real time. In the daily routine anesthesia, it mainly serves for identification of the correct intubation and adaptation of the respiratory minute volume to be applied; however, capnography can also provide much more far-reaching and clinically particularly valuable information, especially in the form of volumetric capnography (VCap) that is not yet so widely clinically available. These include monitoring and optimization of ventilation and assessment of gas exchange. This article presents parameters for making decisions at the bedside, which could previously only be obtained by extensive, more invasive, nonautomated procedures. [ABSTRACT FROM AUTHOR]

Capnography is the graphical representation of the carbon dioxide (CO2) concentration in expired air. Using this monitoring procedure, the kinetics of CO2 of mechanically ventilated patients can be assessed in a noninvasive way and in real time. This article highlights the importance, particularly of volumetric capnography (VCap), for clinical monitoring of mechanically ventilated patients. The procedure provides important information on the breathing, ventilation, metabolism and hemodynamics of patients. [ABSTRACT FROM AUTHOR]

Background: Protective mechanical ventilation is recommended for patients with acute respiratory distress syndrome (ARDS), but it usually requires controlled ventilation and sedation. Using neurally adjusted ventilatory assist (NAVA) or pressure support ventilation (PSV) could have additional benefits, including the use of lower sedative doses, improved patient–ventilator interaction and shortened duration of mechanical ventilation. We designed a pilot study to assess the feasibility of keeping tidal volume (VT) at protective levels with NAVA and PSV in patients with ARDS. Methods: We conducted a prospective randomized crossover trial in five ICUs from a university hospital in Brazil and included patients with ARDS transitioning from controlled ventilation to partial ventilatory support. NAVA and PSV were applied in random order, for 15 min each, followed by 3 h in NAVA. Flow, peak airway pressure (Paw) and electrical activity of the diaphragm (EAdi) were captured from the ventilator, and a software (Matlab, Mathworks, USA), automatically detected inspiratory efforts and calculated respiratory rate (RR) and VT. Asynchrony events detection was based on waveform analysis. Results: We randomized 20 patients, but the protocol was interrupted for five (25%) patients for whom we were unable to maintain VT below 6.5 mL/kg in PSV due to strong inspiratory efforts and for one patient for whom we could not detect EAdi signal. For the 14 patients who completed the protocol, VT was 5.8 ± 1.1 mL/kg for NAVA and 5.6 ± 1.0 mL/kg for PSV (p = 0.455) and there were no differences in RR (24 ± 7 for NAVA and 23 ± 7 for PSV, p = 0.661). Paw was greater in NAVA (21 ± 3 cmH2O) than in PSV (19 ± 3 cmH2O, p = 0.001). Most patients were under continuous sedation during the study. NAVA reduced triggering delay compared to PSV (p = 0.020) and the median asynchrony Index was 0.7% (0–2.7) in PSV and 0% (0–2.2) in NAVA (p = 0.6835). Conclusions: It was feasible to keep VT in protective levels with NAVA and PSV for 75% of the patients. NAVA resulted in similar VT, RR and Paw compared to PSV. Our findings suggest that partial ventilatory assistance with NAVA and PSV is feasible as a protective ventilation strategy in selected ARDS patients under continuous sedation. Trial registration ClinicalTrials.gov (NCT01519258). Registered 26 January 2012, https://clinicaltrials.gov/ct2/show/NCT01519258 [ABSTRACT FROM AUTHOR]

Background: There is a lack of data describing the risk factors for extubation failure (EF) or tracheostomy placement in pediatric neurocritical care (NCC) patients.Methods: A retrospective chart review of children admitted to the pediatric intensive care unit who were intubated for >24 h with an acute neurocritical illness and had an extubation attempt. Bivariate and multivariate statistical analysis was performed to determine significant associations of demographic, neurologic, pulmonary, and clinical variables with EF and tracheostomy placement. Analysis of predictive factors for EF (within 48 h) and tracheostomy placement during the hospitalization was conducted on a first extubation attempt group (n = 193) and a second attempt group (n = 23) who experienced either EF or a "late re-intubation" (>48 h-7 days).Results: Traumatic brain injury (37.3%) and seizures/status epilepticus (31.4%) were the most common diagnoses with neuromuscular weakness patients having the highest risk for EF and tracheostomy placement. EF occurred in 20/193 (10.4%) patients after their first attempt and 6/23 (26.1%) after a second attempt. Compared to those with a fair/strong cough, patients with a weak/absent cough had a relative risk (RR) of 9.4 for EF (95% CI, 4.9-17.9, p < 0.001) and 6.7 (95% CI, 2.3-18.9, p = 0.01) for tracheostomy placement on the first and second attempts, respectively. Glasgow Coma Score (GCS), endotracheal tube (ETT) secretion characteristics, and pulmonary variables were not associated with EF or tracheostomy placement.Conclusions: A weak/absent cough reflex is associated with an increased risk of failing extubation and placement of a tracheostomy in intubated pediatric NCC patients. [ABSTRACT FROM AUTHOR]

Purpose: Some patients presenting with acute respiratory failure and meeting the Berlin criteria for acute respiratory distress syndrome (ARDS) lack exposure to common risk factors (CRF). These so-called ARDS mimickers often lack histological diffuse alveolar damage. We aimed to describe such ARDS mimickers lacking CRF (ARDS CRF-) in comparison with others (ARDS CRF+).Methods: Retrospective study including all patients receiving invasive mechanical ventilation for ARDS admitted to the intensive care units (ICUs) of two tertiary care centers from January 2003 to December 2012.Results: The prevalence of ARDS CRF- was 7.5 % (95 % CI [5.5-9.5]; n = 50/665). On the basis of medical history, bronchoalveolar lavage fluid cytology, and chest CT scan patterns, four etiological categories were identified: immune (n = 18; 36 %), drug-induced (n = 13; 26 %), malignant (n = 7; 14 %), and idiopathic (n = 12; 24 %). Although the ARDS CRF- patients had a lower logistic organ dysfunction score (4 [3-8] vs. 10 [6-13]; p < 0.0001) and less often shock upon ICU admission (44 vs. 80 %; p < 0.0001) than their counterparts, their overall ICU mortality rate was very high (66 % [46-74]), and the absence of CRF remained associated with ICU mortality by multivariable logistic regression analysis (adjusted OR = 2.06; 95 % CI [1.02-4.18]; p = 0.044). Among ARDS CRF- patients, the presence of potentially reversible lung lesions with corticosteroids (aOR = 0.14; 95 % CI [0.03-0.62]) was associated with ICU survival.Conclusions: The absence of CRF among patients with ARDS is common and associated with a higher risk of mortality. For such atypical ARDS, a complete diagnostic workup, including bronchoalveolar lavage fluid cytology and chest CT scan patterns, should be performed to identify those patients who might benefit from specific therapies, including corticosteroids. [ABSTRACT FROM AUTHOR]

Since the development of the classic laryngeal mask airway (LMA) in the late 1980s, there has been a continuous increase in the frequency of its use as well as areas of application. While contraindications to its use for elective procedures must be recognized, there are an increasing number of clinical studies on expanded indications for the use of supraglottic airway (SGA) devices, particularly those of the second generation. The present article describes the added features of the second generation LMAs, with special emphasis on the behavior of these devices in position and performance tests. An appraisal is conducted based on the currently available literature on the value of the utility for indications, such as prolonged use, laparoscopic surgery, obesity, prone position and Cesarean section. [ABSTRACT FROM AUTHOR]

Background: Competence in airway management and maintenance of oxygenation and ventilation represent fundamental skills in emergency medicine. The successful use of laryngeal tubes (LT, LT-D, LTS II) to secure the airway in the prehospital setting has been published in the past. However, some complications can be associated with the use of a laryngeal tube. Methods: In a nonconsecutive case series, problems and complications associated with the use of the laryngeal tube in prehospital emergency medicine as seen by independent observers in the emergency room are presented. Results: Various problems and possible complications associated with the use of a laryngeal tube in eight case reports are reported: incorrect placement of the laryngeal tube in the trachea, displacement and/or incorrect placement of the laryngeal tube in the pharynx, tongue and pharyngeal swelling with subsequently difficult laryngoscopy, and inadequate ventilation due to unrecognized airway obstruction and tension pneumothorax. Conclusion: Although the laryngeal tube is considered to be an effective, safe, and rapidly appropriable supraglottic airway device, it is also associated with adverse effects. In order to prevent tongue swelling, after initial prehospital or in-hospital placement of laryngeal tube and cuff inflation, it is important to adjust and monitor the cuff pressure. Article in English. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate a novel standardized protocol in this neurological weaning unit in order to optimize the weaning process for patients subjected to prolonged mechanical ventilation. Of primary interest were the frequency of and reasons for deviating from the protocol as well as risk factors for weaning failure and mortality. Patients and methods: All patients admitted to the weaning unit were enrolled in this prospective observational study. The weaning protocol consisted of 22 discrete weaning steps. An individual weaning approach was only begun if the standardized protocol failed. Variables for risk analysis included age, body mass index, APACHE II score, reason for initiating mechanical ventilation, total duration of inpatient stay before admission to the weaning unit, extent of mechanical ventilation period before admission, chronic pulmonary diseases and dialysis. Results: Between October 2007 and December 2008 a total of 644 consecutively admitted patients were enrolled in the study. The mean age was 67.6 ± 12.3 years, the mean inpatient stay before admission was 45.8 ± 34.9 days and the mean duration of mechanical ventilation before admission to the unit was 38.1 ± 28.7 days. The mean APACHE II score was 19.0 ± 7.2, 68 % of the patients were male, 98.6 % had a tracheotomy tube, 30.9 % had a history of chronic pulmonary disease and 13.7 % required dialysis. Reasons for initiating ventilation were cerebral 33.1 %, pulmonary 28.7 %, cardiovascular 31.5 %, neuropathic 2.8 %, myopathic 0.9 %, spinal cord injuries 1.9 % and 1.1 % were unclear. Weaning was successful in 77.3 % (498 patients) of all cases with a mean duration of 22.0 ± 33.9 days. Of those successfully weaned, a total of 85.9 % (n = 428) were weaned according to the standard protocol. The weaning process was also shorter (20.8 ± 35.6 versus 29.0 ± 19.9 days) for those patients weaned according to the protocol compared to those patients where the protocol failed. Protocol failure was normally due to complications during the weaning process. Among the patients where the protocol failed, chronic pulmonary disease (41.4 versus 28.3 %; p < 0.02), a longer duration of ventilation (42.3 ± 22.8 versus 35.9 ± 25.3 days; p < 0.01) and a longer in-hospital stay (52.7 ± 41.4 versus 42.4 ± 30.1 days; p < 0.01) prior to admission were significantly more common. A total of 23.0 % (n = 148) of the patients died and 9.8 % (n = 63) of the patients were discharged into a home care ventilation program. Chronic pulmonary disease and the duration of inpatient stay prior to admission were predictors of weaning failure. The APACHE II score, age and acute renal failure with concomitant need for dialysis were the factors best predicting mortality. Conclusions: The majority of patients receiving prolonged mechanical ventilation can be successfully weaned using a standardized protocol. Failures of standardized weaning per protocol occurred most often in patients with chronic pulmonary disease and following longer inpatient stay. These patients also had a higher risk of final weaning failure. [ABSTRACT FROM AUTHOR]

Purpose: Our objective was to revise the definition of acute respiratory distress syndrome (ARDS) using a conceptual model incorporating reliability and validity, and a novel iterative approach with formal evaluation of the definition. Methods: The European Society of Intensive Care Medicine identified three chairs with broad expertise in ARDS who selected the participants and created the agenda. After 2 days of consensus discussions a draft definition was developed, which then underwent empiric evaluation followed by consensus revision. Results: The Berlin Definition of ARDS maintains a link to prior definitions with diagnostic criteria of timing, chest imaging, origin of edema, and hypoxemia. Patients may have ARDS if the onset is within 1 week of a known clinical insult or new/worsening respiratory symptoms. For the bilateral opacities on chest radiograph criterion, a reference set of chest radiographs has been developed to enhance inter-observer reliability. The pulmonary artery wedge pressure criterion for hydrostatic edema was removed, and illustrative vignettes were created to guide judgments about the primary cause of respiratory failure. If no risk factor for ARDS is apparent, however, objective evaluation (e.g., echocardiography) is required to help rule out hydrostatic edema. A minimum level of positive end-expiratory pressure and mutually exclusive PaO/FiO thresholds were chosen for the different levels of ARDS severity (mild, moderate, severe) to better categorize patients with different outcomes and potential responses to therapy. Conclusions: This panel addressed some of the limitations of the prior ARDS definition by incorporating current data, physiologic concepts, and clinical trials results to develop the Berlin definition, which should facilitate case recognition and better match treatment options to severity in both research trials and clinical practice. [ABSTRACT FROM AUTHOR]

A case of pulmonary edema after the administration of naloxone for laparoscopic splenectomy is reported. Previous reports of naloxone-induced pulmonary edema are listed and reviewed. The clinical course is compared to other forms of non-cardiogenic pulmonary edema. Uncertainty remains about the underlying pathophysiological process and the true impact of naloxone on the development of pulmonary edema. [ABSTRACT FROM AUTHOR]

Objective: The European Resuscitation Council recommends that only rescuers experienced and well-trained in airway management should perform endotracheal intubation. Less trained rescuers should use alternative airway devices instead. Therefore, a concept to train almost 1,100 emergency physicians (EP) and emergency medical technicians (EMT) in prehospital airway management using the disposable laryngeal tube suction (LTS-D) is presented. Methods: In five operational areas of emergency medicine services in Germany and Switzerland all EPs and EMTs were trained in the use of the LTS-D by means of a standardized curriculum in the years 2006 and 2007. The main focus of the training was on different insertion techniques and LTS-D use in children and infants. Subsequently, all prehospital LTS-D applications from 2008 to 2010'were prospectively recorded. Results: None of the 762 participating EMTs and less than 20% of the EPs had previous clinical experience with the LTS-D. After the theoretical (practical) part of the training, the participants self-assessed their personal familiarity in using the LTS-D with a median value of 8 (8) and a range of 2-10 (range 1-10) of 10 points (1: worst, 10: best). Within the 3-year follow-up period the LTS-D was used in 303 prehospital cases of which 296 were successfully managed with the device. During the first year the LTS-D was used as primary airway in more than half of the cases, i.e. without previous attempts of endotracheal intubation. In the following years such cases decreased to 40% without reaching statistical significance. However, the mean number of intubation attempts which failed before the LTS-D was used as a rescue device decreased significantly during the study period (2008: 2.2 ± 0.3; 2009: 1.6 ± 0.4; 2010: 1.7 ± 0.3). Conclusion: A standardized training concept enabled almost 1,100 rescuers to be trained in the use of an alternative airway device and to successfully implement the LTS-D into the prehospital airway management algorithm. Because the LTS-D recently became an accepted alternative to endotracheal intubation in difficult airway scenarios, the number of intubation attempts before considering an alternative airway device is steadily decreasing. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficiency, safety and outcome of high flow nasal cannula oxygen (HFNC) in ICU patients with acute respiratory failure. Methods: Pilot prospective monocentric study. Thirty-eight patients were included. Baseline demographic and clinical data, as well as respiratory variables at baseline and various times after HFNC initiation during 48 h, were recorded. Arterial blood gases were measured before and after the use of HFNC. Noise and discomfort were monitored along with outcome and need for invasive mechanical ventilation. Results: HFNC significantly reduced the respiratory rate, heart rate, dyspnea score, supraclavicular retraction and thoracoabdominal asynchrony, and increased pulse oxymetry. These improvements were observed as early as 15 min after the beginning of HFNC for respiratory rate and pulse oxymetry. PaO and PaO/FiO increased significantly after 1 h HFNC in comparison with baseline (141 ± 106 vs. 95 ± 40 mmHg, p = 0.009 and 169 ± 108 vs. 102 ± 23, p = 0.036; respectively). These improvements lasted throughout the study period. HFNC was used for a mean duration of 2.8 days and a maximum of 7 days. It was never interrupted for intolerance. No nosocomial pneumonia occurred during HFNC. Nine patients required secondary invasive mechanical ventilation. Absence of a significant decrease in the respiratory rate, lower oxygenation and persistence of thoracoabdominal asynchrony after HFNC initiation were early indicators of HFNC failure. Conclusions: HFNC has a beneficial effect on clinical signs and oxygenation in ICU patients with acute respiratory failure. These favorable results constitute a prerequisite to launching a randomized controlled study to investigate whether HFNC reduces intubation in these patients. [ABSTRACT FROM AUTHOR]

Difficult airway situations both expected and unexpected, present major challenges to every anesthesiologist, especially in pediatric anesthesia. However, the integration of extraglottic airway devices, such as the laryngeal mask, into the algorithm of difficult airways has improved the handling of difficult airway situations. A device for establishing a supraglottic airway, the laryngeal tube (LT), was introduced in 1999. The LT is an extraglottic airway designed to secure a patent airway during either spontaneous breathing or controlled ventilation. The design of the device has been revised several times and a further development is the LTS II/LTS-D, which provides an additional channel for the insertion of a gastric drain tube. This article reports on the successful use of the LTS II in 12 children aged from 2 days to 6 years when endotracheal intubation, alternative mask or laryngeal mask ventilation failed. Use of the LTS II was associated with a high level of success, securing the airway when other techniques had failed. The potential advantage of the LTS II over the standard LT is an additional suction port, which allows gastric tube placement and can be used as an indirect indicator of correct placement. With a modified insertion technique using an Esmarch manoeuvre, placement was simple and fast to perform. In emergency situations when direct laryngoscopy fails or is too time-consuming the LTS II tube is recommended as an alternative device to secure the airway. As with all extraglottic airway devices, familiarity and clinical experience with the respective device and the corresponding insertion technique are essential for safe and successful use, especially in emergency situations. [ABSTRACT FROM AUTHOR]

Traditionally, specific ventilators have been manufactured to only provide neonatal mechanical ventilation. However, many of the current generation of ICU ventilators also include a neonatal mode. Using the IngMar ASL5000 lung simulator the Puritan Bennett 840, the Maquet Servo i, the Viasys AVEA, the GE Engström, the Drager Evita XL and Babylog 8000 Plus were evaluated during assisted ventilation in the pressure assist/control mode. Three lung mechanics were set: resistance 50 cmH2O/L/s, compliance 2 mL/cmH2O; resistance 100 cmH2O/L/s, compliance 1 mL/cmH2O; and resistance 150 cmH2O/L/s, compliance 0.5 mL/cmH2O. A maximum negative pressure drop of 4 and 7 cmH2O was achieved during simulated inspirations. Each ventilator was evaluated with PEEP 5 cmH2O, peak pressure 20 cmH2O and inspiratory time 0.3 s and with PEEP 10 cmH2O, peak pressure 30 cmH2O and inspiratory time 0.4 s. Each ventilator setting was then repeated with a leak of 0.3 L/min at a constant pressure of 5 cmH2O. Overall each of the 5 ICU ventilators responded faster or greater than the Babylog with respect to: pressure to trigger (except the Servo i), time to trigger (except the Evita XL), time between trigger and return of pressure to baseline, time from start of breath to 90% of peak pressure (except the Avea) and pressure time product of breath activation. Expiratory tidal volume was also greater with all ICU ventilators except the Avea. Variation in mechanics, leak, PEEP and muscular effort had little effect on these differences. All ICU ventilators tested were able to at least equal the performance of the Babylog 8000 Plus on all variables evaluated. [ABSTRACT FROM AUTHOR]

Mechanically ventilated patients with status asthmaticus who undergo prolonged paralysis are at risk for severe weakness due to myopathy. In the mid-1990s, we changed our usual method of achieving tolerance of ventilatory support in asthmatic patients from continuous paralysis to deep sedation. This study examines the impact of this change in practice on the development of clinically significant weakness in status asthmaticus. Retrospective cohort study in university-affiliated county hospital. Mechanically ventilated asthmatic patients seen before ( n = 96) and after ( n = 74) a clinical practice change in 1995 that markedly restricted use of paralytics. The duration of neuromuscular paralysis declined sharply after 1995 (23.7 ± 42.2 vs. 1.8 ± 4.0 h, P < 0.001), but this was not associated with a significant difference in the incidence of weakness (21 vs. 14%, P = 0.23). Within the post-1995 cohort, there was no significant difference in the duration of paralysis for weak and non-weak patients (3.5 ± 6.2 vs. 1.5 ± 3.5 h, P = 0.10). However, weak patients had a much longer duration of mechanical ventilation than did patients without weakness (11.9 ± 3.6 vs. 1.9 ± 1.8 days, P < 0.001). Mechanically ventilated patients with status asthmaticus who are immobilized for prolonged periods of time by deep sedation remain at risk for clinically significant weakness. [ABSTRACT FROM AUTHOR]

Nebulized amikacin may be an attractive option for the treatment of lung infections. Low systemic absorption may permit the use of high doses, leading to high lung concentrations without systemic toxicity. We evaluated the pharmacokinetics and safety of an optimized high-dose amikacin nebulization technique. in vitro and in vivo pharmacokinetic study. Six healthy volunteers (age 21–30 years, weight 49–68 kg). The Aeroneb Pro nebulizer with an Idehaler vertical spacer was evaluated in a bench study. Amikacin was administered intravenously (15 mg/kg) and nebulized (40, 50, and 60 mg/kg) during noninvasive pressure-support ventilation through a mouthpiece. Median (interquartile range) in vitro inhaled fraction was 31% (30–32) and inhalable output was 681 mg/h (630–743). Serum concentrations after nebulization were less than or equal to those after infusion. The area under the serum concentration curve was significantly higher after infusion (138 mg h–1l–1, 122–143) than after nebulization (49 mg h–1l–1, 39–55, at 40 mg/kg; 63, 53–67 at 50; 66, 50–71, at 60). Peak serum concentration was also higher after infusion: 48 mg/l (45–49) after infusion compared to 8.2 (5.6–8.7), 9.2 (7.6–10.2), and 9.2 (5.2–10.3), respectively. Mean absorption times after nebulization were 2 h 24 min (2,07–2,45), 2 h 21 min (2,07–2,35), and 2 h 5 min (2,00–2,25), respectively. No side effect was observed. Nebulization of up to 60 mg/kg amikacin appears to be safe in healthy subjects and associated with lower serum concentrations than a 15 mg/kg infusion. [ABSTRACT FROM AUTHOR]

To avoid ventilator induced lung injury, tidal volume should be low in acute lung injury (ALI). Reducing dead space may be useful, for example by using a pattern of inspiration that prolongs the time available for gas distribution and diffusion within the respiratory zone, the mean distribution time (MDT). A study was conducted to investigate how MDT affects CO2 elimination in pigs at health and after ALI. Randomised crossover study in the animal laboratory of Lund University Biomedical Center. Healthy pigs and pigs with ALI, caused by surfactant perturbation and lung-damaging ventilation were ventilated with a computer-controlled ventilator. With this device each breath could be tailored with respect to insufflation time and pause time ( T I and T P) as well as flow shape (square, increasing or decreasing flow). The single-breath test for CO2 allowed analysis of the volume of expired CO2 and the volume of CO2 re-inspired from Y-piece and tubes. With a long MDT caused by long T I or T P, the expired volume of CO2 increased markedly in accordance with the MDT concept in both healthy and ALI pigs. High initial inspiratory flow caused by a short T I or decreasing flow increased the re-inspired volume of CO2. Arterial CO2 increased during a longer period of short MDT and decreased again when MDT was prolonged. CO2 elimination can be enhanced by a pattern of ventilation that prolongs MDT. Positive effects of prolonged MDT caused by short T I and decreasing flow were attenuated by high initial inspiratory flow. [ABSTRACT FROM AUTHOR]

Objective: To compare the effectiveness of open and closed endotracheal suction in recovering thin and thick secretions in normal and injured lungs during conventional and high frequency ventilation.Design and Setting: Randomised study in a paediatric intensive care model in the animal research laboratory of a tertiary paediatric hospital.Subjects: 16 New Zealand White rabbits.Interventions: Anaesthetised animals were intubated with a 3.5-mm endotracheal tube. Simulated thin and thick secretions (iopamidol 2 ml, a watery radio-opaque fluid, and fluorescent mucin 1 ml) were instilled in turn 1 cm below the tube tip through a catheter placed via a tracheostomy. Open or closed suction, randomly assigned, was applied for 6s at -140 mmHg using a 6-F gauge catheter. Following lung injury with repeated saline lavage the procedure was repeated on conventional and high frequency ventilation.Measurements and Results: Iopamidol recovery was determined by digitally subtracting the post-contrast and post-suction radiographic images. Mucin recovery was determined by fluorescence assay of the aspirate. In the normal lung similar amounts were recovered by both suction methods. In the lavaged lung closed suction recovered less iopamidol during conventional (22 +/- 7.5%) and high frequency ventilation (11 +/- 2.4%) than open suction (36 +/- 2% and 22 +/- 8.1%, respectively). Mucin recovery was less with closed suction during conventional 32 +/- 28 microl) and high frequency ventilation (30 +/- 31 microl) than with open suction (382 +/- 235 microl and 24 +/- 153 microl).Conclusions: In the injured lung closed suction was less effective than open suction at recovering thin and thick simulated secretions, irrespective of ventilation mode. [ABSTRACT FROM AUTHOR]

Prognosis of patients with ischemic stroke requiring mechanical ventilation (MV) has been reported to be poor. However, longterm survival and functional outcome have scarcely been studied and nothing is known about the prevalence of cognitive impairment or depression in survivors and their quality of life (QoL). We identified all patients treated for acute ischemic stroke on a Neurological Intensive Care Unit during 3.5 years who required MV for more than 24 hours. Early mortality rate at 2 months and survival rates at 1 and 2 years were determined. Survivors were examined for functional outcome (modified Rankin Scale (mRS), Barthel Index), cognitive impairment (Mini Mental State Examination (MMSE)), depression (Beck Depression Inventory, BDI) and QoL (Short Form–36). Clinical characteristics on admission were analyzed for prognostic significance. Of 101 consecutive patients, 44% died within 60 days. Survival rates at 1 and 2 years were 40% and 33%, respectively.Age > 60 years (p = 0.002) and Glasgow Coma Scale score < 10 on admission (p = 0.002) were independent predictors of early and late mortality. History of myocardial infarction (p = 0.007) independently predicted late mortality at 2 years. Of 33 surviving patients, nine (27%) had a good functional outcome (mRS 0–2). Of 27 survivors who could be interviewed, 17 (63%) had no cognitive impairment (MMSE > 24) and 20 (74%) did not suffer from relevant depression (BDI < 19). In conclusion, longer–term survival of patients with ischemic stroke requiring MV was 33% and every fourth survivor resumed an independent life without dementia or depression. Older patients comatose on admission and with concomitant cardiovascular disease had the lowest probability of a favorable outcome. [ABSTRACT FROM AUTHOR]

Objective: Invasive aspergillosis is associated with a poor prognosis, especially in critically ill patients with cerebral involvement. We present two cases of cerebral invasive aspergillosis successfully treated in the intensive care unit with combination antifungal therapies and without surgery.Case Presentation: The first patient was a 49-year-old man with rheumatoid arthritis who received corticosteroid and cyclophosphamide treatment and developed pulmonary and cerebral invasive aspergillosis. After failure of voriconazole the patient had a successful outcome with voriconazole and liposomal amphotericin B therapy. The patient returned home after an 8-month hospital stay. The second patient was a 54-year-old woman with pulmonary neoplasia and corticosteroid treatment who developed pulmonary and cerebral invasive aspergillosis. After failure of voriconazole and liposomal amphotericin B therapy the patient had a favorable outcome with liposomal amphotericin B and caspofungin therapy. The patient died 10 months after initial diagnosis of cardiac tamponade unrelated to fungal infection.Discussions: These cases illustrate the improving prognosis of invasive aspergillosis due to the availability of new treatments, especially in cases of cerebral involvement. It also demonstrates that the outcome of critically ill patients requiring mechanical ventilation for invasive aspergillosis can be favorable. The treatment of patients with invasive cerebral aspergillosis in the intensive care setting should be encouraged. [ABSTRACT FROM AUTHOR]

Objective: Use of lung-protective mechanical ventilation (MV) by applying lower tidal volumes is recommended in patients suffering from acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). Recent data suggest that lung-protective MV may benefit non-ALI/ARDS patients as well. This study analyzed tidal volume settings in three ICUs in The Netherlands to determine the effect of feedback and education concerning use of lung-protective MV.Design and Setting: Observational study in one academic and two nonacademic "closed format" ICUs.Patients: Intubated mechanically ventilated subjects.Interventions: Feedback and education concerning lung-protective MV with special attention to the importance of closely adjusting tidal volumes to predicted body weight (PBW).Results: Tidal volumes declined significantly within 6 months after intervention (from 9.8+/-2.0 at baseline to 8.1+/-1.7 ml/kg PBW) as the percentage of undesirable ventilation data points, defined as tidal volumes greater than 8 ml/kg PBW (84% vs. 48%). There were no differences between patients meeting the international definition criteria for ALI/ARDS and those not. Only four patients received tidal volumes less than 6 ml/kg PBW. Lower tidal volumes were still used after 12 months. Tidal volumes in patients on mandatory MV and patients breathing on spontaneous modes were similar.Conclusions: Feedback and education improve physician compliance in use of lung-protective MV. [ABSTRACT FROM AUTHOR]

Objective: Measurements from the pulmonary pressure-volume (PV) curve have been proposed to adjust ventilator settings. We investigated the effects of repeated construction of an inflation PV curve implemented in a standard ventilator on recruitment or derecruitment in acutely injured lungs.Design and Setting: Prospective experimental animal study in eight anesthetized and mechanically ventilated pigs.Interventions: Acute lung injury was induced by lung lavage and animals were ventilated in volume controlled mode with PEEP 10 cmH(2)O. The PV curve was constructed five times repeatedly by constant pressure rise, after which ventilation with the preset PEEP was resumed immediately. Studies of hemodynamics, lung mechanics, blood gases and computed tomography were carried out before and after maneuvers.Measurements and Results: Derecruitment was assessed as an increase in nonaerated lung volume (V(NON)), and V(PEEP) was the end-expiratory volume difference between PEEP and ZEEP. There was a significant decrease in PaO(2) from 90.4+/-33.3 to 70.9+/-36.3 mmHg and a rise in venous admixture from 47.8+/-12.7 to 59.1+/-16.6%. V(PEEP) was reduced from 244 to 202 ml. A corresponding decrease in normally aerated lung volume was observed, while regression analysis revealed increase in V(NON) depending on the amount of preexisting atelectasis.Conclusions: Repeated generation of the PV curve with a readily available tool resulted in worsened oxygenation. Derecruitment of the lungs occurred with loss of PEEP at the start of the maneuver, which could not be recovered by a maximum inflation pressure of 40 cmH(2)O. Repeated use of the investigated tool should be cautioned, and users should consider measures to preserve aerated lung volumes. [ABSTRACT FROM AUTHOR]

Objective: Earlier reports suggested that transthoracic (TTE) determination of the ratio of mitral inflow E wave velocity to early diastolic mitral annulus velocity (E/E') measured by tissue Doppler imaging (TDI) closely approximates PAOP in cardiac patients. However, the value of E/E' for PAOP assessment in ICU patients has not been evaluated. This study assessed whether the E/E' ratio provides an accurate estimation of pulmonary artery occlusion pressure (PAOP) in mechanically ventilated ICU patients.Design and Setting: Prospective, open, clinical study in the ICU of a university hospital.Patients: Twenty-three consecutive mechanically ventilated patients.Interventions: Volume expansion in 14 patients.Measurements and Results: Doppler TTE or TEE mitral inflow and TDI mitral annulus velocities were determined and compared with PAOP measured using a Swan-Ganz catheter. Of all the Doppler variables studied the best correlations were observed between PAOP and the lateral (r=0.84) and medial (r=0.76) annulus E/E' ratio and remained highly significant when the analysis was restricted to TEE (r=0.91 and 0.86) or TTE (r=0.73 and 0.61). The sensitivities and specificities of estimating PAOP at 15 mmHg or higher were, respectively, 86% and 81% for lateral E/E' above 7.5 and 76% and 80% for medial E/E' above 9. PAOP changes after volume expansion (700+/-230 ml) were limited and accurately assessed by repeated E/E' determinations.Conclusions: In mechanically ventilated ICU patients TTE or TEE E/E' determinations using TDI closely approximate PAOP. [ABSTRACT FROM AUTHOR]

Objective: Inhalation of perfluorocarbons (PFC) has been suggested as a new and promising technique of PFC delivery in animal models of severe lung injury. However, no in vitro data were available on the efficacy of PFC aerosolization during mechanical ventilation. Therefore, the aim of the in vitro study was to investigate the influence of physical properties of PFC and the ventilatory settings on the amount of PFC delivered into the lung.Design: In vitro lung model study.Setting: University research laboratory.Measurements and Results: Two different PFC (PF 5080 and PFOB) were aerosolized with a PariBoy jet nebulizer. Using a PFC selective adsorber, the effect of endotracheal tube size (2 mm and 3 mm diameter) on delivery of PFC was investigated. PFC delivery was estimated by continuous measurement of weight gain of the adsorber (adsorption rate). Finally, the influence of respiratory rate and tidal volume on adsorption rate (AR) was studied. AR was significantly reduced by a decreasing tube diameter and ranged from 1.45+/-0.03 ml/min (no tube) to 0.93+/-0.03 ml/min (2.0 mm) for PF 5080 (vapor pressure 51 mmHg) and from 0.49+/-0.06 ml/min to 0.32+/-0.04 ml/min for PFOB (11 mmHg). PFC-aerosolization into a ventilatory circuit with simulation of spontaneous tidal breathing (minute volume 600 ml) reduced AR to 0.16+/-0.02 ml/min. During mechanical ventilation, changes in respiratory rate and tidal volume, which reduce minute ventilation, caused a decrease in AR.Conclusion: The amount of PFC that can be delivered into the lung by aerosolization is very small and is influenced by PFC properties, tube size, and ventilatory settings. [ABSTRACT FROM AUTHOR]