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Environmental concerns are forcing the replacement of the commonly used refrigerants and finding new fluids is a top priority. The hydro-fluoro-olefin (HFO) R1234ze(E), because of its smaller global warming potential (GWP) and shorter atmospheric lifetime, replaced R134a. Accordingly, for HVAC systems design, a detailed knowledge of the thermo-fluid-dynamic characteristics of the fluids and reliable predictive models are required. To improve the understanding, R134a and R1234ze(E) were employed in convective condensation experiments (saturation temperature Tsat = 35°C, mean quality xm = 0.1~0.9, quality changes Δx = 0.05~0.6, mass flux G = 43~444 kg·m−2s−1) inside a microfin tube (outer diameter D = 9.52 mm, fin number n = 60, fin height H = 0.2 mm). The results were used for two goals: the former is the comparison of the heat transfer features of the two fluids, while the latter aims at testing the performance of prediction models available in the open literature. At the saturation temperature T = 35°C, the two fluids show small differences in the thermal properties so that, as expected, the experiments highlighted a very similar behavior in the typical operating conditions of HVAC systems. In fact, for all the operating conditions marginal differences were observed in the pressure drop, the heat transfer coefficient and the flow pattern maps. The issue of prediction reliability, however, is still open. Actually, not all the models achieving good results for R134a show the same performance for R1234ze(E), especially for the pressure drop.

Environmental concerns are forcing the replacement of commonly used refrigerants, and finding new fluids is a top priority. Soon the R134a will be banned, and the hydro-fluoro-olefin (HFO) R1234ze(E) has been indicated as an alternative due to its smaller global warming potential (GWP) and shorter atmospheric lifetime. Nevertheless, for an optimal replacement, its thermo-fluid-dynamic characteristics have to be assessed. Flow boiling experiments (saturation temperature Tsat = 5 °C, mass flux G = 65 ÷ 222 kg·m−2·s−1, mean quality xm = 0.15 ÷ 0.95, quality changes ∆x = 0.06 ÷ 0.6) inside a microfin tube were performed to compare the pressure drop per unit length and the heat transfer coefficient provided by the two fluids. The results were benchmarked for some correlations. In commonly adopted operating conditions, the two fluids show a very similar behavior, while benchmark showed that some correlations are available to properly predict the pressure drop for both fluids. However, only one is satisfactory for the heat transfer coefficient. In conclusion, R1234ze(E) proved to be a suitable drop-in replacement for the R134a, whereas further efforts are recommended to refine and adapt the available predictive models.

Odour emissions from complex industrial plants may cause potential impacts on the surrounding areas. Consequently, the validation of effective tools for the control of the associated environmental pressures, without hindering economic growth, is strongly needed. Nowadays, senso-instrumental methods by using Instrumental Odour Emissions Systems (IOMSs) is among the most attractive tool for the continuous monitoring of environmental odours, allowing the possibility of obtaining real-time information to support the decision-making process and proactive approach. The systems complexity and scarcity of real data limited their wider full-scale employment. The study presents an advanced prototype of IOMS for the continuous classification and quantification of the odours emitted in ambient air by complex industrial plants, to continuously control the plants emissions with backwards approach. The IOMS device was designed and optimized and included the system for the automatic control of the conditions inside the measurement chamber. The designed operational procedures were presented and discussed. Results highlighted the influence of temperature and air flow rate for the measurement repeatability. Accurate prediction model was created and optimized and resulted able to distinguish 3 different industrial odour sources with accuracy approximately equal to 96%. The models were optimized thanks to the software features, which allowed to automatically apply the designed statistical procedures on the identified dataset with different pre-processing approach. The usefulness of having a fully-developed and user-friendly flexible system that allowed to select and automatically compare different settings options, including the different feature extraction methods, was demonstrated in order to identify the best prediction model.

A study on the influence of the substrate roughness on the occurrence and the formation mechanisms of air bubbles entrapped into water drops impinging on polymeric surfaces, typified by distinctive superficial grinding (15 ⩽ R q ⩽ 1159 nm), was conducted by digitizing silhouettes of the impacting droplets. The images were processed to determine the drop outer profile, the morphology of an air cavity formed at the center of the droplet during the droplet deformations, and the shape of the enclosed bubble. The fluid dynamic processes leading to the entrapment of the bubble were meticulously analyzed, and three new formation mechanisms were observed and detailed. The investigation was conducted for different droplet sizes (2.13 ⩽ D 0 ⩽ 3.87 mm), and at a wide range of impact velocities (0.14 ⩽ V i ⩽ 0.59 m/s). The entrapped bubbles were more likely found into drops falling on more rugged surfaces, while were rare or totally absent into drops impinging on less rough substrates. However, considering just impacts on more rugged surfaces, the bubble occurrence appeared to be minimally influenced by the substrate roughness. At fixed roughness, the bubbles were caught into droplets impinging at lower velocities with increasing the drop size. For fixed drop size and substrate roughness, the range of the bubble existence was often split in two distinctive intervals of impact velocities, phenomenon especially noted for drops impacting on more rugged surfaces. Finally, we suggested a relation between the peculiar shapes that the liquid assumed in the course of the impact and the occurrence/absence of the entrapped bubble.

A study on the occurrence and formation mechanisms of air bubbles entrapped into water drops impinging onto four graphite substrates, typified by distinctive hydrophobicities and surface topographies, was conducted by digitizing silhouettes of the impacting droplets. The images were taken sequentially immediately after the drop impingement by using a high-speed video camera system, and then processed to determine the drop edge coordinates. The profiles of the impacting droplet, the air cavity and the entrapped bubble were, thus, identified. The formation of the entrapped bubble was meticulously analyzed, and five diverse mechanisms were observed and minutely detailed in this study. During the retraction phase, the bubbles were trapped since the top liquid layer of the drop closed down an air cavity previously formed at the center of the drop. The bubble was caught into the drop just when the flow of the liquid over the top of the air cavity moved inward faster than the upwards movement of the fluid below the cavity. The investigation was conducted for different impacting droplet sizes (1.91 ≤ D 0 ≤ 4.87 mm), and for a wide range of impact velocities (0.11 ≤ V i ≤ 0.74 m/s), so that the system conditions for occurrence and formation mechanisms of the entrapped bubble were clearly identified.

Could a unique receding contact angle be indicated for describing the wetting properties of a real gas-liquid-solid system? Could a receding contact angle be defined if the triple line of a sessile drop is not moving at all during the whole measurement process? To what extent is the receding contact angle influenced by the intrinsic properties of the system or the measurement procedures? In order to answer these questions, a systematic investigation was conducted in this study on the effects of substrate roughness and relative humidity on the behavior of pure water drops spreading and evaporating on polycarbonate (PC) surfaces characterized by different morphologies. Dynamic, advancing, and receding contact angles were found to be strongly affected by substrate roughness. Specifically, a receding contact angle could not be measured at all for drops evaporating on the more rugged PC surfaces, since the drops were observed strongly pinning to the substrate almost until their complete disappearance. Substrate roughness and system relative humidity were also found responsible for drastic changes in the depinning time (from ∼10 to ∼60 min). Thus, for measurement observations not sufficiently long, no movement of the triple line could be noted, with, again, the failure to find a receding contact angle. Therefore, to keep using concepts such as the receding contact angle as meaningful specifications of a given gas-liquid-solid system, the imperative to carefully investigate and report the inner characteristics of the system (substrate roughness, topography, impurities, defects, chemical properties, etc.) is pointed out in this study. The necessity of establishing methodological standards (drop size, measurement method, system history, observation interval, relative humidity, etc.) is also suggested.

Droplet impingement experiments at low Weber numbers were conducted by digitizing silhouettes of impacting water drops onto unlike graphite substrates, typified by different advancing water contact angles ( θ a ): 140 and 160°. The relaxation of wetting diameter, dynamic contact angle, and drop shapes were measured. The purpose was to carefully investigate the phenomenology and possible causes of the failure of the superhydrophobicity. During impact and spreading phases, all the drops impinging onto both graphite substrates showed a similar behavior. Then, after an initial free recoil, drops impinging at lower impact velocities onto graphite substrates characterized by θ a = 140° clearly exhibited time intervals in which the wetting diameter appeared to be almost constant. The duration of this pinned phase was observed decreasing with increasing the impact height and almost completely disappearing for drops impinging at higher impact velocities. This behavior has never been reported before, and, contrariwise, water droplets impinging at lower impact velocities onto hydrophobic and superhydrophobic surfaces have been generally observed more freely retracting, and ultimately rebounding, compared to drops impacting at higher velocities. In the present study, this latter behavior was recorded just for drops impinging onto graphite surfaces characterized by θ a = 160°. A theoretical description of the experimental results was proposed, specifically investigating the role of dynamic pressure, hammer pressure and liquid penetration time during the impact, spreading and recoil stages.

Droplet impingement experiments at low Weber number ( W e = 7.61) were conducted by digitizing silhouettes of impacting water drops onto four graphite surfaces with different hydrophobicities. The relaxation of the wetting diameter, the droplet height and the dynamic contact angle were determined for characterizing the peculiar impact and spreading dynamics for the unalike surfaces, typified by four distinctive topographies carefully analyzed by scanning electron microscopy. After the initial inertially dominated phase, during which the drops spreading onto all substrates showed a similar behavior, the expected recoil phase was not observed for droplets impacting onto graphite surfaces characterized by 90° and 120° advancing contact angles. A few milliseconds after the impact, the drops exhibited a pinned configuration due to the peculiar morphology of these graphite substrates: randomly distributed cavities on a generally smooth surface, in fact, stopped the movement of the triple line. This behavior, however, was not detected for water droplets impinging onto graphite surfaces characterized by 160° advancing contact angles, which instead presented the usual retraction phase. Finally, the graphite surface characterized by 140° advancing contact angles showed a mixed behavior due to a transition of the drop configuration from Cassie-Baxter to Wenzel state.

Droplet impingement experiments for a wide range of Weber numbers were conducted by digitizing silhouettes of impacting water drops onto a tailored grinded graphite substrate, typified by randomly distributed cavities on a generally smooth surface. The aim was to investigate if the anchoring of the triple line, due to friction forces generated by dilute superficial defects, could be observed for drop impingement experiments. During the early inertially dominated spreading phase, the drops showed similar behaviors independently of the initial impact velocities. However, just after this phase, droplets impacting at low Weber numbers indeed exhibited this peculiar friction-induced pinned configuration.

In this study, the evaporation of water drops on four distinctive polymeric substrates, acrylonitrile butadiene styrene, polycarbonate, poly(methylmethacrylate) and poly(vinyl chloride), typified by unlike superficial morphologies, was investigated using the sessile drop method coupled with a video-enhanced image digitization technology and a best-fitting algorithm. The correlations between the observed dissimilar dynamics of the three phases contact line during the water drop evaporative process and the aforementioned surface topographies were deeply analyzed and discussed. The evaporation dynamics were measured and intensively illustrated in terms of the variation of contact angle, wetting diameter, drop height, drop volume, and drop shape. While the drops sitting on surfaces characterized by numerous defects and inhomogeneities showed a pinned triple line for almost their whole lifetime, for drops deposited on smoother substrates, after an initial pinning stage, the three phases contact line was observed receding freely until the drop disappearance.

The surface tension of boron trioxide was measured with uncertainty less than ±0.5 mN/m in the temperature range between 500 °C and 900 °C, using the pendant drop method coupled with a video enhanced image digitization technology and a best-fitting algorithm. These accurate surface tension data showed a peculiar temperature dependence: a mild increase at temperatures between 500 °C and 800 °C followed by a strong increase at T > 800 °C. To explain this unusual temperature coefficient of the surface tension, a change in the boron oxide structure while raising the temperature was proposed in this study. The main component of the vitreous B2O3 network, the planar boroxol ring, breaks up when the temperature increases. However, hypothesizing an analogy with the superstructures that are present in the binary borate glasses, this breakdown is compensated by the formation of new groups characterized by four-fold coordinated borons and three-dimensional structure. The presence of these groups causes a general strengthening of the B2O3 structure, especially noticeable at the complete breakdown of the boroxol rings. This proposed model of the structure changes successfully interprets the singular behavior of the surface tension temperature coefficient of the boron trioxide.

The wetting of graphite by molten silver was investigated at the temperature range from 1000 to 1350 °C using the sessile drop method coupled with a video-enhanced image digitization technology and a best-fitting algorithm. At the temperature range from 1100 to 1175 °C the contact angle θ was observed suddenly increasing and then decreasing, repeatedly. A similar behavior was not found in the comparison test performed on wetting of refractory (ZrO2) by molten silver at the same range of temperature. A surface analysis of the graphite used in the measurements was performed, showing a rings-shaped surface morphology. The correlation between the wetting diameters, the ring diameters and the observed drop contractions was then brought out. The measured contact angle decreases while a “trough” forms at the three phases contact line. At the observed θ sudden increase, the drop is actually “jumping out” from the trough, since the rate of the formation of the trough is lower than the rate at which the drop changes its shape. The process then starts again, with the formation of a new trough. The measured θ is obviously affected by the trough geometry.

The aim of the study was to determine variables that could be used to predict survival in patients with ruptured abdominal aortic aneurysm (RAAA) and to assess the accuracy of the Glasgow Aneurysm Score (GAS) and the Acute Physiology Chronic Health Evaluation II (APACHE-II). From January 1998 to July 2006, 103 patients underwent operations for RAAA. For each patient, 44 variables were retrospectively recorded in a database. Data were analyzed with univariate and multivariate methods. In the univariate analysis significant predictors of death were hypotension (p=0.001), preexisting peripheral vascular disease (p0.001), renal insufficiency (p=0.037), chronic obstructive pulmonary disease (p=0.028), level of HCO(3)(-) (p0.001), intraperitoneal rupture (p=0.001), blood transfused (p0.001), cardiac complications (p0.001), and APACHE-II score (p=0.001). Multivariate analysis confirmed statistical significance for coexisting peripheral vascular disease (p0.001), diastolic blood pressure at admission60 mm Hg (p=0.039), APACHE-II score18.5 (p=0.025), HCO(3)(-)21 mg/dL (p0.001), and intraperitoneal rupture of the aneurysm (p=0.011) as predictors of death. Results of the study suggested that different factors can be helpful in identifying those patients whose operative risk is prohibitive. APACHE-II, contrary to GAS, is an accurate system to predict postoperative death after repair for RAAA.

El objetivo de este estudio fue determinar las variables de utilidad para predecir la supervivencia en los pacientes con rotura de aneurisma aortico abdominal (RAAA) y evaluar la precision de los sistemas de puntuacion Glasgow Aneurysm Score (GAS) y Acute Physiology Chronic Health Evaluation II (APACHE-II). Entre enero de 1998 y julio de 2006, 103 pacientes fueron sometidos a intervenciones con RAAA. En cada paciente se registraron 44 variables de forma retrospectiva en una base de datos. Los datos fueron analizados mediante metodos uni y multivariante. En el analisis multivariante, los factores significativos predictores de fallecimiento fueron: hipotension (p = 0,001), vasculopatia periferica preexistente (p 18,5 (p = 0,025), HCO-3

Les buts de l'etude etaient de determiner les variables qui pourraient etre employees pour prevoir la survie des patients presentant un anevrysme de l'aorte abdominale rompu (AAAR) et d'evaluer l'exactitude des scores Glasgow pour anevrysme (GAS) et APACHE-II. De janvier 1998 a juillet 2006, 103 patients ont ete operes pour AAAR. Pour chaque patient, 44 variables ont ete retrospectivement enregistrees dans une base de donnees. Les donnees ont ete analysees avec des methodes univariees et multivariees. Dans l'analyse univariee les facteurs predictifs significatifs de mortalite etaient l'hypotension (p = 0,001), l'existence d'une atteinte vasculaire peripherique (p 18.5 (p = 0,025), du taux de HCO3

The aim of this study was to compare several parameters of GH/IGF-I axis activity in septic and trauma patients during Intensive Care Unit (ICU) stay. To this goal, 13 patients with sepsis (SEP) and 16 with trauma (TRA) were studied. Thirty-three adult subjects (AS) were studied as controls. Serum IGF-I and -II, IGFBP-1, -2 and -3, GH and GHBP levels were studied on day 1, 3, 5 and 7 after ICU admission, during comparable artificial nutrition in SEP and TRA and basally in AS. In 5 patients with SEP and 6 with TRA, the GH response to GHRH was evaluated on day 3. On ICU day 1, IGF-I and -II and IGFBP-3 in SEP were lower (p

Fulminant hepatic failure is a rare, but often fatal complication of acute viral hepatitis. This condition, in absence of orthotopic liver transplantation (OLTx) surgery, is associated with a high mortality rate, despite the improvement of general intensive care. Plasma-exchange (PEx) therapy has been long used to treat FHF, in particular by removing toxic substances and correcting the severe coagulopathy. In this study we describe our experience with PEx treatment of FHF, beginning in 1982. Seventy patients affected with FHF due to various causes (HBV=40; cryptogenic/non-A, non-E=15; Amanita phalloides=8; other=7) were treated with PEx (altogether 348 sessions). Overall survival rate, comprising patients undergoing OLTx, was 51%, a little higher than what we observed in patients (N=49) treated solely by PEx, i.e., 41%. The best outcome predictor was FHF aetiology, owing to the good survival rate in patients with Amanita phalloides intoxication and the very poor prognosis of patients suffering from cryptogenic/non-A, non-E FHF. Moreover, the marked increase in prothrombin time and alpha-fetoprotein levels after 48 hours from admission was associated with a good prognosis, whereas the patient's age and coma grade were not clearly predictive of survival. Additionally, lymphocyte subpopulation, resulting in a CD4/CD8 ratio lower than 1.0 along with CD8 activation with HLA-DR strong expression, were associated with a high rate of mortality and morbidity. Our data indicate that PEx therapy can improve survival in patients with sufficient residual capacity of liver regeneration. Moreover, the identification of certain prognostic factors may be useful for the rational planning of therapeutic strategy in FHF.

Summary The objective of this study was an evaluation of the prevalence of myopathies in paediatric patients scheduled for orthopaedic surgery (clubfoot) performed under regional anaesthesia. Seventeen infants scheduled for lower limb orthopaedic surgery were studied to verify coexisting neuromuscular disorders with electromyography and muscle biopsy during surgery. All surgical procedures were performed under caudal block or spinal anaesthesia, associated with light general anaesthesia. No major cardiorespiratory, neurological or malignant hyperthermic complications (muscle rigidity, arrhythmias, hyperpyrexia) were observed. Combined neurological, electromyographic and biopsy studies showed a high rate of myopathic changes (70%). Performance of clubfoot surgery under light general anaesthesia with regional techniques was free from any problems. The high rate of myopathic changes (70%) observed in the muscle biopsies suggests that precautions should be taken with paediatric patients for clubfoot surgery and a regional anaesthesia technique with adequate monitoring may be helpful to prevent possible malignant hyperthermia related problems.

The tracheal esophageal combitube has been successfully used in many difficult airway circumstances. We report the dramatic case of a morbidly obese patient with a well-known difficult airway who was successfully rescued from a cannot ventilate-cannot intubate situation in our critical care unit by using the tracheal esophageal combitube. Surgical tracheostomy was performed while she was mechanically ventilated through the tracheal esophageal combitube. The tracheal esophageal combitube is a very important device that should be kept available in all cases of morbidly obese airway management.

Defibrotide (Df) has been reported to protect various organs from ischemic damage. The aim of this study was to evaluate the effect of Df on renal function and morphology after warm kidney ischemia. Divided into two groups, 14 pigs underwent bilateral renal clamping for 90 min. One group (7 pigs) was treated with Df (32 mg/kg per h) for 6 h, whereas the control group received 5000 IU of heparin. Serum levels of blood urea nitrogen (BUN) and creatinine measured for 6 days were significantly higher in the control group (peak 26.8 +/- 16.7 vs 11.0 +/- 2.9 mmol/l and 501.2 +/- 351.4 vs 230.2 +/- 68.0 mumol/l P0.05). Renal biopsy evidenced a lesser extent of tubular and endothelial damage in Df-treated animals. In conclusion, Df provided relevant protection against renal ischemic injury.

Medical care costs represent a large proportion of the gross domestic product in developed countries, and intensive care units (ICUs) consume a significant amount of those resources. The aim of this review is to analyze how the healthcare cost problem is studied in critically ill patients.Permanent staffing and other overhead costs have the greatest impact on ICU costs. A growing number of studies from around the world are quantifying the costs of ICU care. Mechanical ventilation, particularly in severely ill patients, and sepsis management are responsible for much of the economic burden in the ICU. New expensive therapies and life support systems make formal economic analyses necessary.Although economic justification should not be the only issue to influence treatments offered in the ICU, increasing use of tools such as cost-benefit analyses is needed to help with medical decisions on the critically ill patient.

Recombinant activated factor VII (rFVIIa) has been successfully used ‘‘off-label’’ in patients with refractory life-threatening hemorrhage. Intravenous rFVIIa was given to 31 patients unresponsive to standard therapy with blood products and surgical reexploration, who were bleeding due to trauma, surgery, organ transplantation, liver cirrhosis, ruptured uterus. We recorded their coagulation and hematologic profiles, acid-base balance, blood loss, number of red blood cells (RBC), plasma and platelet transfusions, complications, and survival. rFVIIa (mean dose 132.2 ± 56.3 μg/kg) effectively contained the hemorrhage in 28/31 (90.3%) cases, with a mean reduction in blood loss from 12.4 ± 10.2 to 2.7 ± 2.2 L (P < .0001). The need for RBC, platelet, and plasma transfusion decreased significantly after rFVIIa, with a consequent significant improvement in clotting of test hematocrit, pH, and bicarbonates. Four patients had adverse events potentially related to rFVIIa. The survival rates after 1 and 30 days were 48.4% and 29.1%, respectively.

The tracheal esophageal combitube has been successfully used in many difficult airway circumstances. We report the dramatic case of a morbidly obese patient with a well-known difficult airway who was successfully rescued from a cannot ventilate-cannot intubate situation in our critical care unit by using the tracheal esophageal combitube. Surgical tracheostomy was performed while she was mechanically ventilated through the tracheal esophageal combitube. The tracheal esophageal combitube is a very important device that should be kept available in all cases of morbidly obese airway management.

The goal of the present multicenter, prospective, randomized clinical investigation was to compare the clinical efficacy and safety of sevoflurane and isoflurane during maintenance of and recovery from general anaesthesia in adult patients.With the approval of the Ethical Committee and the patient informed consent, 143 ASA physical status I-II patients, aged 18-65 years, were randomized in order to receive either isoflurane (n = 71) or sevoflurane (n = 72) as the main general anaesthetic. After an oral diazepam (0.1-0.2 mg kg-1) and atropine (0.007-0.01 mg kg-1) premedication and a standardized intravenous induction, general anaesthesia was maintained by adjusting the end-tidal concentrations of the inhalational agent for the maintainance of cardiovascular stability. At the end of surgery the anaesthetic vapours were discontinued, and the neuromuscular block was reversed; the following times were recorded: time of eyes opening, time of command response and suitability for discharge from the recovery area. The occurrence of any untoward event was also recorded. Preoperatively and 24 hr after surgery, blood was collected in order to assess renal an hepatic functions.No differences in demography, duration of surgery, exposure to the inhalational agent and haemodynamic effects were observed between the two groups. Patients receiving sevoflurane showed shorter times for the achievement of extubation (median: 9 min versus 13 min, p = 0.002), eyes opening (median: 10 min versus 13 min, p = 0.002), command response (11 min versus 15 min, p = 0.002) and suitability for discharge from recovery room (median: 19 min versus 22 min, p0.05) than those receiving isofluorane. No intra- and intergroup differences were observed in pre- and post-operative laboratory testing of renal and hepatic function.We conclude that sevoflurane, when compared to isoflurane, provides a similarly safe maintenance but allows for a more rapid emergence from general anaesthesia.

Cervical spine injuries are quite uncommon in children. When occurring, these lesions are of particular concern for the anaesthesiologist. This case refers to an hangman's fracture diagnosed in a four-month-old female infant, which probably occurred at birth. We describe the anaesthetic management adopted in this infant undergoing diagnostic procedures and conservative treatment. The problems related to airway control and the anaesthetic management utilized to diagnose and treat this unusual paediatric pathology are highlighted.

Opioids are among the most ancient and widely used drugs in anaesthesiology. The pharmacology of opioid analgesics and their receptors is a complex and not fully understood matter; even more complex are the interactions between different classes of opioids at both molecular and clinical levels. We want to report here a clinical observation to emphasize the importance of the theoretical basis of anaesthesiology. This paper contains a clinical observation of respiratory depression following the administration of buprenorphine as postoperative analgesic after balanced anaesthesia with fentanyl. The observed case is interpreted in the light of the pharmacokinetics and pharmacodynamics of the different classes of opioid drugs (agonists, agonists-antagonists, antagonists) and of the interactions with their respective receptors.

Spinal anesthesia in day-care surgery is still controversial because of the possibility of postdural puncture headache (PDPH). The use of the Sprotte needle with a conical tip that spreads the dural fibers may reduce the incidence of PDPH. The aim of this study was to compare the 22-gauge and 25-gauge Sprotte needles with respect to PDPH and postoperative complaints in out-patients undergoing arthroscopy. The rate of spinal anesthesia failure and the feasibility of unilateral spinal anesthesia when using a low dose of anesthesia was also verified. For this randomized, prospective study, 234 patients undergoing elective arthroscopy were chosen. Patients were allocated randomly to have spinal anesthesia with either a 22-gauge or 25-gauge Sprotte needle. Dural puncture was performed with the patient in a lateral flexed decubitus position. After the injection of anesthetic solution (0.5-1.2 mL of 1% bupivacaine in 8% glucose) patients remained in the lateral decubitus position for 30 min. The time to regression of analgesia, time of micturition, and all postoperative complaints were recorded. The most frequent side effect was backache (10.2%) with a more frequent incidence in the group using the 22-gauge needle (14.5% and 5.9%, respectively). PDPH was recorded in only one patient (0.8%) in the group using the 22-gauge needle. The failure rate was 0.8%. Unilateral anesthesia was achieved in 88% of 213 patients. Our data indicate that the use of spinal block is a suitable technique in the ambulatory setting, with a low rate of unplanned hospital admission.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to evaluate the possibility of using a selective subarachnoid anesthesia in ambulatory surgery we studied its feasibility with a Sprotte needle 24 G in 103 patients (range 15-67 years) undergoing a knee joint arthroscopy. The subarachnoid anesthesia was achieved with Sprotte needle 24 G with introducer with patient on lateral decubitus. Hyperbaric bupivacaine 1% (0.05 mg/cm height) was used in order to obtain a selective homolateral metameric anesthesia between L1 and S3. The numbers of attempts were 1.29 (range 1-4). We involved the homolateral determatomeres in 94% of our attempts, adding a weak anesthetic action on contralateral ones. In the remaining 6% of the patients the anesthesia was bilateral and extending in an overlying manner. Anesthesia was adequate for the time needed to perform all the surgical procedures. Nevertheless in 3 patients the tourniquet was painful. We registered systemic hypotension only in 2% of the patients (a reduced systolic pressure value30%). No cases of postdural puncture headache were registered. Non postural atypical headache was seem in 3.9% of the patients. Urinary retention necessitating catheterization was noted only in 3 cases. A weak backache was revealed in 8.8%. When interviewed after surgery, 98% of our patients fulfilled the technique. In spite of technical difficulties that the use of the Sprotte needle may present, the selective subarachnoid anesthesia may be a safe alternative to the other anesthetic procedures for ambulatory surgery of the legs.

The availability of a long-term central venous access for the management of neoplastic and chronic patients is extremely important in order to achieve an easy and safe infusion of chemotherapeutic drugs, blood components, and parenteral nutrition. The authors evaluated 26 adult patients (25 with malignant tumors and 1 with severe asthma) in whom implantable catheter systems were placed subcutaneously between February 1989 and March 1992. Catheters were inserted through the cephalic vein in 13 cases, the subclavia vein in 8 cases and jugular vein in 5 cases. The mean function time was 262 days in deceased patients and 155 in alive ones. There were no infective or thromboembolic complications. The authors, in agreement with the literature, confirm that TIS represent a safe and easy access for a long term i.v. therapy, with a very low complication rate. Furthermore, comfort of the patients is substantially improved and nursing care is greatly facilitated.

The nutritional and immunological status have been evaluated in 28 consecutive patients with esophageal cancer. Patients (21 male and 7 female), had a mean age of 61 years, ranging from 34 to 84 years. The tumor histological type was squamous in 25 patients. A melanoma, an oat cell carcinoma and a adenocarcinoma were observed in the remaining cases. The nutritional status was assessed by means of weight loss, triceps skinfold, midarm muscle circumference and serum levels of albumin and transferrin. On the basis of this data the patients were divided into two groups: A, 19 patients (68%), normal nourished group (or with a mild malnutrition) and B, 9 patients (32%) with a severe malnutrition. The immunological status was assessed by determining the lymphocyte absolute number (H-6000-Technicon), the T-Lymphocyte sub-populations (flow-cytometry with monoclonal antibodies--Ortho Diagnostic System) and the patient's response to intradermally placed recall antigens (Multitest Merieux). Significative immunological abnormalities were found only in malnourished patients, group B (p less than 0.05). Moreover a reduction of OKT4 helper (less than 30%) and the inversion of OKT4/OKT8 ratio (less than 0.9%) were also observed only in the malnourished group (p less than 0.01). Therefore, we conclude that acquired immunodeficiency, when present in patients with esophageal cancer, is due to the severe malnutrition rather than to the cancer itself.

The clinical course and the treatment of two patients with chronic idiopathic pseudo-obstruction are reported. Venting enterostomy to reduce the frequency of the occlusive symptoms and home parenteral nutrition to correct malnutrition have been employed, after the failure of aggressive medical treatment with prokinetic drugs. These measures improved symptoms of obstructions and allowed the reestablishment of oral alimentation. Therefore, according to medical literature, we suggest that patients with chronic idiopathic pseudo-obstruction can be safety managed for prolonged period with this treatment.

The central venous catheterization (CVC) by subclavian vein puncture for total parenteral nutrition (TPN) has a high risk of complications in some situations such as neck or supraclavicular diseases, tracheostomies, costoclavicular deformities and coagulopathies. Surgical CVC approach to the basilic vein is indicated in these cases. The aim of this study was to evaluate the usefulness of this technique. Sixteen patients had TPN with this technique, utilizing a silicon catheter (Vygon Nutricath). The main time of TPN was 19 days (min 5-max 41). In 12 cases (75%), there were no complications. In two cases (12.5%) we observed an accidental catheter displacement. The incidence of thrombophlebitis was 12.5% (2 cases); in one of two cases (6.25%), it was correlated with the contamination of the catheter (Staphylococcus epidermidis); in the second case it was aseptic. Our results demonstrated the usefulness of this of these technique in cases in where the CVC by subclavian vein presents a high risk of complications.

The evaluation of probability of death from burn injuries would provide clinicians with an explicit basis for clinical decisions, help them understand the relative contributions of specific prognostic criteria and reduce reliance on clinical intuition [1]. The goal of this study is to estimate the mortality rate and the clinical variables for early assessment of outcome of a severe burn population.

Increased GH together with decreased IGF-I levels suggesting a peripheral GH insensitivity in critically ill patients have been reported by some but not by other authors. To clarify the activity of GH-IGF-I axis in catabolic states, basal and GHRH-stimulated GH secretion and IGF-I levels have been evaluated in patients with sepsis [SEP, n = 11; age (mean ± SEM) 56.1 ± 2.7 years] or trauma (TRA, n = 13; age 42.4 ± 4.1 years) on 1st, 3rd, 5th and 7th day after ICU admission, during artificial nutrition. SAPS II and MOF scores overlapped in both groups. Basal GH and IGF-I levels were also assayed in 24 normal subjects (NS, age 48.1 ± 4.3 years), 54 adult hypopituitaric patients with severe GH deficiency (GHD, age 44.8 ± 2.3 years), 19 patients with anorexia nervosa (AN, age 18.6 ± 0.6 years) and 12 patients with liver cirrhosis (LC, age 50.4 ± 2.8 years). In GHD, basal GH levels were lower than in NS (0.3 ± 0.1 versus 1.4 ± 0.2 μg/l, P < 0.01); similarly, IGF-I levels were markedly reduced and lower than in NS (68.6 ± 6.1 versus 213.5 ± 15.4 μg/l, P < 0.01). AN and LC basal GH levels were similar (10.0 ± 2.8 and 7.7 ± 2.1 μg/l) and higher than in NS (P < 0.01). AN and LC IGF-I levels were similar (70.4 ± 9.1 and 52.4 ± 10.5 μg/l), lower than in NS (P < 0.01) while overlapping with those in GHD. On the 1st day of ICU admission basal GH levels in SEP (0.7 ± 0.3 μg/l) and TRA (1.8 ± 0.6 μg/l) were similar to those in NS. IGF-I levels in SEP were lower than in TRA (82.9 ± 13.0 versus 127.0 ± 16.4 μg/l, P < 0.05) and both lower than in NS (P < 0.01). IGF-I levels in SEP were similar to those in GHD, AN and LC which were lower than in TRA (P < 0.01). GH levels in SEP and TRA remained similar up to the 7th day. In both groups the GH response to GHRH on the 3rd day was nearly abolished, clearly lower than in age-matched NS (GH peak, 2.5 ± 1.2 versus 10.5 ± 1.9 μg/l, P < 0.01). During parenteral nutrition, IGF-I levels increased both in SEP and TRA (P < 0.05 and P < 0.01, respectively). However, on the 7th day, IGF-I levels in SEP were clearly lower than in TRA (110.3 ± 9.5 versus 211.4 ± 25.5 μg/l, P < 0.01), overlapping the latter with those in NS. In conclusion, in severe catabolic conditions due to trauma and furthermore to sepsis, IGF-I levels are markedly low and similar to those in GHD. Somatotrope secretion is also impaired in both these catabolic conditions. Therefore, in patients with severe catabolism due to trauma or, particularly to sepsis, peripheral GH insensitivity and somatotrope insufficiency could both severely impair the activity of GH-IGF-I axis. Finally, artificial nutrition clearly increases IGF-I levels in post traumatic but not in septic catabolic states.

Our previous studies indicate that in critically ill patients ICF-I levels are reduced to a greater extent in septic (S) than in trauma (T) subjects. However, it is well known that IGF-I levels depend on nutrition as well as on somatotrope secretion. Aim of the present study was to verify the levels of IGF-I and other nutritional parameters such as albumin (A), prealbumin (PRE-A), transferrin (TRA) and retinol-binding-globulin (RBG) in septic patients [n = 11, age (mean ± SEM) 56.1 ± 2.7 years, BMI 25.2 ± 0.9 kg/m2] and in trauma patients (n = 13, age 42.4 ± 4.1 years, BMI 25.0 ± 0.8 kg/m2) after ICU admission. Both groups were characterized by similar scores of catabolism (SAPSII and MOF score) and underwent similar artificial nutrition. Nutritional parameters were evaluated on day 1, 3, 5 and 7 after ICU admission. Both in S and in T, IGF-I, A, PRE-A, TRA and RBG levels on day 1 of ICU admission were lower than the normal range. Basal IGF-I levels in S were lower than those in T (82.9 ± 13.0 versus 127.0 ± 16.4 μg/1, P < 0.05). IGF-I levels increased on day 7 to a lower (P < 0.05) extent in S (110.3 ± 9.5, P < 0.05 versus day 1) than in T (211.4 ± 25.5, P < 0.01 versus day 1). Basal A and RBG levels in S (3.0 ± 0.2 g/dl and 2.8 ± 0.9 mg/dl) were similar to those in T (3.2 ± 0.1 g/dl and 3.1 ± 0.3 mg/dl); in both groups A levels did not show variations up to day 7 while RBG showed a trend toward increase (P < 0.05 in S). Basal PRE-A and TRA levels in S (10.9 ± 2.5 mg/dl and 108.8 ± 10.7 mg/dl) were lower (P < 0.01) than those in T (17.8 ± 1.4 mg/dl and 168.7 ± 8.3 mg/dl). PRE-A and TRA levels did not show significant variations up to day 7 persisting lower (P < 0.05) in S than in T. In conclusion, our results further demonstrate that, in spite of similar score of catabolism, in critically ill patients the reduction of IGF-I, PRE-A and TRA levels is more marked in septic than in trauma patients. These findings indicate that the influence of nutrition and/or somatotrope function on ICF-I synthesis and release varies among different catabolic states.

We report 298 patients admitted to the Neurosurgical unit of the University of Padua during one calendar year. We divided the patients into two groups. “in coma” and “not in coma”, and analyze their data records. The time between injury and admission to a neurosurgical centre is important for therapy as well as for transport. The necessity of an “Admission Chart” is emphasized.

The Authors investigated the usefulness of some biochemical markers of visceral protein synthesis (TSF, TBPA and RBP) in 24 patients affected with gynecological cancer and treated with Total Parenteral Nutrition in the perioperative period. The absence of an improving TSF and TBPA is related to increased morbidity and mortality.