Peri-operative respiratory adverse events in children with upper respiratory tract infections allowed to proceed with anaesthesia: A French national cohort study.

BACKGROUND: Peri-operative respiratory adverse events (PRAEs) in paediatric patients with upper respiratory tract infections (URTIs) remain inadequately explored in patients allowed to proceed to anaesthesia and surgery. OBJECTIVE: To determine the incidence and risk factors of PRAE in children with URTI allowed to proceed to anaesthesia. DESIGN: Multicentre cohort study performed over 6 months in France. SETTING: Sixteen centres with dedicated paediatric anaesthetists. PATIENTS: Eligible patients were aged from 0 to 18 years with URTI symptoms on admission or a history of such over the preceding 4 weeks. MAIN OUTCOMES: The primary outcome of the study was to determine predictors of PRAE. Secondary outcomes were: predictors of peri-operative arterial desaturation and of the decision to proceed with anaesthesia and surgery in children with URTI. RESULTS: Overall, 621 children were included and 489 (78.7%) anaesthetised. Of those anaesthetised, 165 (33.5%) and 97 (19.8%) experienced PRAE and arterial desaturation, respectively. Factors predictive of PRAE included patient age, tracheal intubation and the absence of midazolam premedication. Factors predictive of peri-operative arterial desaturation included patient age, anaesthetist experience, endoscopic procedures and the presence of other PRAE. Factors predicting proceeding to anaesthesia in the context of URTI included anaesthetist experience, emergency procedures and the absence of severe URTI symptoms. CONCLUSION: The risk of PRAE in patients anaesthetised in the presence of URTI was similar to previous publications - close to 30%. In the light of our findings, first, current rescheduling indications should be questioned, and second, further medical and organisational strategies should be investigated to reduce PRAE in children with URTI. TRIAL REGISTRATION: The study was registered in the European Networks of Centers for Pharmacoepidemiology and Pharmacovigilance (EUPAS16436).

Development and validation of a risk score to predict the probability of postoperative vomiting in pediatric patients: the VPOP score.

BACKGROUND: Few data are available in the literature on risk factors for postoperative vomiting (POV) in children. OBJECTIVE: The aim of the study was to establish independent risk factors for POV and to construct a pediatric specific risk score to predict POV in children. METHODS: Characteristics of 2392 children operated under general anesthesia were recorded. The dataset was randomly split into an evaluation set (n = 1761), analyzed with a multivariate analysis including logistic regression and backward stepwise procedure, and a validation set (n = 450), used to confirm the accuracy of prediction using the area under the receiver operating characteristic curve (ROCAUC ), to optimize sensitivity and specificity. RESULTS: The overall incidence of POV was 24.1%. Five independent risk factors were identified: stratified age (>3 and <6 or >13 years: adjusted OR 2.46 [95% CI 1.75-3.45]; ≥6 and ≤13 years: aOR 3.09 [95% CI 2.23-4.29]), duration of anesthesia (aOR 1.44 [95% IC 1.06-1.96]), surgery at risk (aOR 2.13 [95% IC 1.49-3.06]), predisposition to POV (aOR 1.81 [95% CI 1.43-2.31]), and multiple opioids doses (aOR 2.76 [95% CI 2.06-3.70], P < 0.001). A simplified score was created, ranging from 0 to 6 points. Respective incidences of POV were 5%, 6%, 13%, 21%, 36%, 48%, and 52% when the risk score ranged from 0 to 6. The model yielded a ROCAUC of 0.73 [95% CI 0.67-0.78] when applied to the validation dataset. CONCLUSIONS: Independent risk factors for POV were identified and used to create a new score to predict which children are at high risk of POV.

Pupillary reflex measurement predicts insufficient analgesia before endotracheal suctioning in critically ill patients.

INTRODUCTION: This study aimed to evaluate the pupillary dilatation reflex (PDR) during a tetanic stimulation to predict insufficient analgesia before nociceptive stimulation in the intensive care unit (ICU). METHODS: In this prospective non-interventional study in a surgical ICU of a university hospital, PDR was assessed during tetanic stimulation (of 10, 20 or 40 mA) immediately before 40 endotracheal suctionings in 34 deeply sedated patients. An insufficient analgesia during endotracheal suction was defined by an increase of ≥1 point on the Behavioral Pain Scale (BPS). RESULTS: A total of 27 (68%) patients had insufficient analgesia. PDR with 10 mA, 20 mA and 40 mA stimulation was higher in patients with insufficient analgesia (P <0.01). The threshold values of the pupil diameter variation during a 10, 20 and 40 mA tetanic stimulation to predict insufficient analgesia during an endotracheal suctioning were 1, 5 and 13% respectively. The areas (95% confidence interval) under the receiver operating curve were 0.70 (0.54 to 0.85), 0.78 (0.61 to 0.91) and 0.85 (0.721 to 0.954) with 10, 20 and 40 mA tetanic stimulations respectively. A sensitivity analysis using the Richmond Agitation Sedation Scale (RASS) confirmed the results. The 40 mA stimulation was poorly tolerated. CONCLUSIONS: In deeply sedated mechanically ventilated patients, a pupil diameter variation ≥5% during a 20 mA tetanic stimulation was highly predictable of insufficient analgesia during endotracheal suction. A 40 mA tetanic stimulation is painful and should not be used.

Balanced versus chloride-rich solutions for fluid resuscitation in brain-injured patients: a randomised double-blind pilot study.

INTRODUCTION: We sought to investigate whether the use of balanced solutions reduces the incidence of hyperchloraemic acidosis without increasing the risk for intracranial hypertension in patients with severe brain injury. METHODS: We conducted a single-centre, two-arm, randomised, double-blind, pilot controlled trial in Nantes, France. Patients with severe traumatic brain injury (Glasgow Coma Scale score ≤8) or subarachnoid haemorrhage (World Federation of Neurosurgical Society grade III or higher) who were mechanically ventilated were randomised within the first 12 hours after brain injury to receive either isotonic balanced solutions (crystalloid and hydroxyethyl starch; balanced group) or isotonic sodium chloride solutions (crystalloid and hydroxyethyl starch; saline group) for 48 hours. The primary endpoint was the occurrence of hyperchloraemic metabolic acidosis within 48 hours. RESULTS: Forty-two patients were included, of whom one patient in each group was excluded (one consent withdrawn and one use of forbidden therapy). Nineteen patients (95%) in the saline group and thirteen (65%) in the balanced group presented with hyperchloraemic acidosis within the first 48 hours (hazard ratio = 0.28, 95% confidence interval [CI] = 0.11 to 0.70; P = 0.006). In the saline group, pH (P = .004) and strong ion deficit (P = 0.047) were lower and chloraemia was higher (P = 0.002) than in the balanced group. Intracranial pressure was not different between the study groups (mean difference 4 mmHg [-1;8]; P = 0.088). Seven patients (35%) in the saline group and eight (40%) in the balanced group developed intracranial hypertension (P = 0.744). Three patients (14%) in the saline group and five (25%) in the balanced group died (P = 0.387). CONCLUSIONS: This study provides evidence that balanced solutions reduce the incidence of hyperchloraemic acidosis in brain-injured patients compared to saline solutions. Even if the study was not powered sufficiently for this endpoint, intracranial pressure did not appear different between groups. TRIAL REGISTRATION: EudraCT 2008-004153-15 and NCT00847977.

What is the accuracy of the high-fidelity METI Human Patient Simulator physiological models during oxygen administration and apnea maneuvers?

BACKGROUND: A widely used physiological simulator is generally accepted to give valid predictions of oxygenation status during disturbances in breathing associated with anesthesia. We compared predicted measures with physiological measurements available in the literature, or derived from other models. METHODS: Five studies were selected from the literature which explored arterial oxygenation, with or without preoxygenation, in clinical situations or through mathematical modeling as well as the evolution of the fraction of expired oxygen (Feo2) during preoxygenation maneuvers. Scenarios from these studies were simulated on the METI-Human Patient Simulator™ simulator, and the data were compared with the results in the literature. RESULTS: Crash-induction anesthesia without preoxygenation induces an O2 pulse saturation (Spo2) decrease that is not observed on the METI simulator. In humans, after 8 minutes of apnea, Spo2 decreased below 90% while the worst value was 95% during the simulation. The apnea time to reach 85% was less with obese patients than with healthy simulated patients and was shortened in the absence of preoxygenation. However, the data in the literature include METI simulator confidence interval 95% values only for healthy humans receiving preoxygenation. The decrease in Pao2 during 35-second apnea started at end-expiration was slower on the METI simulator than the values reported in the literature. Feo2 evolution during preoxygenation maneuvers on the METI simulator with various inspired oxygen fractions (100%, 92%, 84%, and 68%) was very close to those reported in humans when perfect mask seal is provided. In practice, this seal is impossible to obtain on the METI simulator. CONCLUSIONS: Spo2 decreased much later during apnea on the METI simulator than in a clinical situation, whether preoxygenation was performed or not. The debriefing after simulation of critical situations or the use of the METI simulator to test a new equipment must consider these results.

Continuous controlled-infusion of hypertonic saline solution in traumatic brain-injured patients: a 9-year retrospective study.

INTRODUCTION: Description of a continuous hypertonic saline solution (HSS) infusion using a dose-adaptation of natremia in traumatic brain injured (TBI) patients with refractory intracranial hypertension (ICH). METHODS: We performed a single-center retrospective study in a surgical intensive care unit of a tertiary hospital. Fifty consecutive TBI patients with refractory ICH treated with continuous HSS infusion adapted to a target of natremia. In brief, a physician set a target of natremia adapted to the evolution of intracranial pressure (ICP). Flow of NaCl 20% was a priori calculated according to natriuresis, and the current and target natremia that were assessed every 4 hours. RESULTS: The HSS infusion was initiated for a duration of 7 (5 to 10) (8 ± 4) days. ICP decreased from 29 (26 to 34) (31 ± 9) mm Hg at H0 to 20 (15 to 26) (21 ± 8) mm Hg at H1 (P < 0.05). Cerebral perfusion pressure increased from 61 (50 to 70) (61 ± 13) mm Hg at H0 up to 67 (60 to 79) (69 ± 12) mm Hg at H1 (P < 0.05). No rebound of ICH was reported after stopping continuous HSS infusion. Natremia increased from 140 (138 to 143) (140 ± 4) at H0 up to 144 (141 to 148) (144 ± 4) mmol/L at H4 (P < 0.05). Plasma osmolarity increased from 275 (268 to 281) (279 ± 17) mmol/L at H0 up to 290 (284 to 307) (297 ± 17) mmol/L at H24 (P < 0.05). The main side effect observed was an increase in chloremia from 111 (107 to 119) (113 ± 8) mmol/L at H0 up to 121 (117 to 124) (121 ± 6) mmol/L at H24 (P < 0.05). Neither acute kidney injury nor pontine myelinolysis was recorded. CONCLUSIONS: Continuous HSS infusion adapted to close biologic monitoring enables long-lasting control of natremia in TBI patients along with a decreased ICP without any rebound on infusion discontinuation.

Hydrocortisone therapy for patients with multiple trauma: the randomized controlled HYPOLYTE study.

CONTEXT: The role of stress-dose hydrocortisone in the management of trauma patients is currently unknown. OBJECTIVE: To test the efficacy of hydrocortisone therapy in trauma patients. DESIGN, SETTING, AND PATIENTS: Multicenter, randomized, double-blind, placebo-controlled HYPOLYTE (Hydrocortisone Polytraumatise) study. From November 2006 to August 2009, 150 patients with severe trauma were included in 7 intensive care units in France. INTERVENTION: Patients were randomly assigned to a continuous intravenous infusion of either hydrocortisone (200 mg/d for 5 days, followed by 100 mg on day 6 and 50 mg on day 7) or placebo. The treatment was stopped if patients had an appropriate adrenal response. MAIN OUTCOME MEASURE: Hospital-acquired pneumonia within 28 days. Secondary outcomes included the duration of mechanical ventilation, hyponatremia, and death. RESULTS: One patient withdrew consent. An intention-to-treat (ITT) analysis included the 149 patients, a modified ITT analysis included 113 patients with corticosteroid insufficiency. In the ITT analysis, 26 of 73 patients (35.6%) treated with hydrocortisone and 39 of 76 patients (51.3%) receiving placebo developed hospital-acquired pneumonia by day 28 (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.30-0.83; P = .007). In the modified ITT analysis, 20 of 56 patients (35.7%) in the hydrocortisone group and 31 of 57 patients (54.4%) in the placebo group developed hospital-acquired pneumonia by day 28 (HR, 0.47; 95% CI, 0.25-0.86; P = .01). Mechanical ventilation-free days increased with hydrocortisone by 4 days (95% CI, 2-7; P = .001) in the ITT analysis and 6 days (95% CI, 2-11; P < .001) in the modified ITT analysis. Hyponatremia was observed in 7 of 76 (9.2%) in the placebo group vs none in the hydrocortisone group (absolute difference, -9%; 95% CI, -16% to -3%; P = .01). Four of 76 patients (5.3%) in the placebo group and 6 of 73 (8.2%) in the hydrocortisone group died (absolute difference, 3%; 95% CI, -5% to 11%; P = .44). CONCLUSION: In intubated trauma patients, the use of an intravenous stress-dose of hydrocortisone, compared with placebo, resulted in a decreased risk of hospital-acquired pneumonia. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00563303.

Oxygen delivery during transtracheal oxygenation: a comparison of two manual devices.

BACKGROUND: The Manujet™ and the ENK Oxygen Flow Modulator™ (ENK) deliver oxygen during transtracheal oxygenation. We sought to describe the ventilation characteristics of these 2 devices. METHODS: The study was conducted in an artificial lung model consisting of a 15-cm ringed tube, simulating the trachea, connected via a flow analyzer and an artificial lung. A 15-gauge transtracheal wire reinforced catheter was used for transtracheal oxygenation. The ENK and Manujet were studied for 3 minutes at respiratory rates of 0, 4, and 12 breaths/min, with and without the artificial lung, in a totally and a partially occluded airway. Statistical analysis was performed using analysis of variance followed by a Fisher exact test; P < 0.05 was considered significant. RESULTS: Gas flow and tidal volume were 3 times greater with the Manujet than the ENK (approximately 37 vs 14 L · min(-1) and 700 vs 250 mL, respectively) and were not dependent on the respiratory rate. In the absence of ventilation, the ENK delivered a 0.6 ± 0.1 L · min(-1) constant gas flow. In the totally occluded airway, lung pressures increased to 136 cm H(2)O after 3 insufflations with the Manujet, whereas the ENK, which has a pressure release vent, generated acceptable pressures at a low respiratory rate (4 breaths/min) (peak pressure at 27.7 ± 0.7 and end-expiratory pressure at 18.8 ± 3.8 cm H(2)O). When used at a respiratory rate of 12 breaths/min, the ENK generated higher pressures (peak pressure at 95.9 ± 21.2 and end-expiratory pressure at 51.4 ± 21.4 cm H(2)O). In the partially occluded airway, lung pressures were significantly greater with the Manujet compared with the ENK, and pressures increased with the respiratory rate with both devices. Finally, the gas flow and tidal volume generated by the Manujet varied proportionally with the driving pressure. DISCUSSION: This study confirms the absolute necessity of allowing gas exhalation between 2 insufflations and maintaining low respiratory rates during transtracheal oxygenation. In the case of total airway obstruction, the ENK may be less deleterious because it has a pressure release vent. Using a Manujet at lower driving pressures may decrease the risk of barotrauma and allow the safe use of higher respiratory rates.

Effects of perioperative intravenous low dose of ketamine on postoperative analgesia in children.

BACKGROUND AND OBJECTIVE: Low dose of ketamine reduces postoperative pain and opioid consumption in adult studies. However, there are only a few data with controversial results in the paediatric population. The aim of this randomized controlled trial was to evaluate the use of low doses of intravenous ketamine on postoperative pain in children after surgery on the lower part of the body. METHODS: Thirty-seven children with ASA 1 or 2 from 6 to 60 months of age, undergoing scheduled surgery, were prospectively enrolled in a double blind sequential trial using a triangular test, with analysis every 10 patients treated. The children were randomly assigned to intravenously receive saline or 0.15 mg kg(-1) ketamine before surgery, followed by a continuous infusion of 1.4 microg kg(-1) min(-1) over 24 h. After sevoflurane induction and tracheal intubation, a caudal anaesthesia was performed in all children (1 ml kg(-1) of bupivacaine 0.25% with epinephrine). The postoperative analgesic technique was standardized with intravenous paracetamol 15 mg kg(-1) 6 h(-1), rectal morniflumate (20 mg kg(-1) 12 h(-1)) and intravenous nalbuphine infusion 1.2 mg kg(-1) 24 h(-1) for 24 h. The Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) scores, additional bolus of nalbuphine (if CHEOPS >7) and side effects were recorded from eye opening every 2 h over 24 h. The primary endpoint was the CHEOPS area under the curve. RESULTS: There was no difference in terms of additional bolus of nalbuphine as well as CHEOPS score area under the curve between groups, that is, 76 +/- 10 in the ketamine group versus 74 +/- 7 in the control group. No psychomimetic side effects were noted. CONCLUSION: The study failed to show any evidence of benefit of ketamine to improve analgesia in children when given in addition to a multimodal analgesic therapy with paracetamol, a NSAID and an opiate.

An opioid-free anaesthetic using nerve blocks enhances rapid recovery after minor hand surgery in children.

BACKGROUND AND OBJECTIVE: The aim of this prospective randomized study was to evaluate the quality of analgesia, postoperative comfort and subsequent duration of hospitalization after distal hand surgery and peripheral nerve block at the wrist for paediatric outpatients. METHODS: Sixty consecutive ASA I or II children were randomly assigned to the following groups: in group B (block), intraoperative and postoperative analgesia was provided by peripheral nerve block; and in group O (opioids), intraoperative and postoperative analgesia was provided by intravenous opioids. The patients' age, sex and type of surgery were recorded as were the postoperative pain management and postoperative vomiting. Time to discharge from the recovery room, the postoperative ward and the time to discharge home were also noted. RESULTS: The two groups were similar with respect to age, sex, ASA physical status, weight, height and types of injuries. The incidence of postoperative pain (CHEOPS score >or=7) and the incidence of postoperative vomiting were significantly higher in group O than in group B: 26.6 versus 3.3%; P = 0.025, and 33.3 versus 6.6%; P = 0.011, respectively. The time before oral intake was significantly longer in group O than in group B [187 (75-265) min versus 60 (32-125) min, respectively, P = 0.0002]. The time to meet discharge home criteria was 277 (230-330) min in group O versus 210 (145-260) min in group B (P = 0.0039). CONCLUSION: The present study demonstrates for the first time that, after distal hand surgery in children, peripheral nerve block improves pain management, opioid analgesia-induced side effects and provides a shorter postoperative recovery time than systemic analgesia with opioids.

Peri-operative management of overweight and obese children and adolescents.

Obesity has become endemic, even in children. Systemic complications associated with obesity include metabolic syndrome, cardiovascular disease, and respiratory compromise. These comorbidities require adequate investigation, targeted optimisation, and, if surgery is required, specific management during the peri-operative period. Specific peri-operative strategies should be used for paediatric patients who are overweight or obese to prevent postoperative complications, and optimising the respiratory function during surgery is particularly crucial. This Review aims to provide up-to-date information on peri-operative management for physicians who are caring for children and adolescents (usually younger than 18 years) who are overweight or obese undergoing surgery, including bariatric surgery. We have particularly focussed on the physiological consequences of obesity-namely, obstructive sleep apnoea, respiratory compromise, and pharmacological considerations.

Training experts in difficult airway management: Evaluation of a continuous professional development program.

OBJECTIVE: The Formation de référents aux techniques d'intubation difficile (FRTID) is a French continuing medical education program on difficult airway management. Its objectives are to train experts in the task of training other physicians in their hospitals for better guideline compliance. Our aim was to describe the curriculum of the experts and to evaluate the program's efficacy via a prospective survey. METHODS: Each participant was asked to complete a questionnaire before (T0), immediately (T1), 6 (T6) and 12 (T12) months after the course. The main criterion was the proportion of the participants who declared that they had implemented at least one action to improve difficult airway management in their institution at 6 months. Other criteria included the proportion of participants who declared that they had modified their own clinical practice and the frequency of use of specific devices assessed on modified Likert numerical rating scales. RESULTS: Two hundred and forty-four participants were included in the survey. One hundred and three, 91 and 62 participants responded to the T1 (immediately after the course), T6 (6 months later) and T12 (12 months later) questionnaires, respectively; 73 physicians (i.e. 30% of all participants and 80% of the survey responders) declared that they had implemented at least one action likely to optimize the management of difficult airways. On the T6 and T12 questionnaires, 91% and 97% of the responders respectively declared that they had changed their clinical practice. The course has resulted in increased use of transtracheal oxygenation with manual devices (Manujet(®), Enk(®)) and Seldinger cricothyroidotomy as well as paediatric difficult airway techniques such as paediatric sized elastic gum and Airtraq™ or fibrescopic intubation under general anaesthesia with spontaneous ventilation (through a laryngeal mask). CONCLUSION: These data encourage the training of experts in difficult airways. This curriculum is contributing to the dissemination of the recommendations among a large number of practitioners.

A retrospective study about cerebral near-infrared spectroscopy monitoring during paediatric cardiac surgery and intra-operative patient blood management.

OBJECTIVES: Cerebral non-invasive monitoring of oxygen saturation by near-infrared spectroscopy (rSO2) during paediatric cardiac surgery is supposed to decrease the risk of neurological complications. Since haemoglobin level is one of the factors changing rSO2, we aimed to explore if rSO2 monitoring influences intra-operative RBC (red blood cell) transfusion threshold and volumes, as well as the duration of ICU stay. METHODS: The design was a retrospective analysis involving 91 children less than 2 years of age (including 16 neonates) with a congenital heart disease requiring surgical treatment with or without cardiopulmonary bypass from January 2006 to August 2009. Systematic rSO2 monitoring was introduced after September 2007 (n=56). The independent factors associated with the intra-operative transfusion threshold haemoglobin (Hb) level>9.5g/dL, total volume of intra-operative RBC transfusion<30mL/kg and ICU stay<6 days were identified by multivariate analysis logistic regression. Data were expressed as medians (25-75%). RESULTS: Cardiac malformations and demographic characteristics were similar in both periods. Two independent factors, weight and rSO2 monitoring, were identified as independent factors associated with the three end-points. The transfusion threshold, total transfusion volume and ICU stay with and without rSO2 were 9.8 (8.9 to 10.3) versus 8.7 (8.2 to 9.6) g/dL (P<0.0001), 20 (14-49) versus 36 (22.5-51.5) mL/kg (P=0.0165) and 5 (3-8) versus 7 (5-10.7) days (P=0.0084), respectively. CONCLUSION: rSO2 monitoring changed our transfusion strategy with an earlier transfusion but a reduced total RBC volume and decreased the length of ICU stay.

0.5% levobupivacaine versus 0.5% ropivacaine: Are they different in ultrasound-guided sciatic block?

CONTEXT AND AIMS: Little is known about onset and duration of sciatic block after 0.5% levobupivacaine (Levo) versus 0.5% ropivacaine (Ropi) for ultrasound-guided technique. We assessed these parameters in the ultrasound-guided block, to know for the practice. SETTING AND DESIGN: A comparative randomized double-blind study was conducted in the University Hospital. MATERIALS AND METHODS: Were included 35 adults of ASA I-II, scheduled for foot surgery, presenting clear imaging of their sciatic nerve at mid-thigh. A volume of 20 mL of either 0.5% Levo or 0.5% Ropi were injected around the sciatic nerve at mid-thigh using ultrasound guidance (out of the plane) followed by placement of a catheter to use, if necessary, for perioperative analgesia. A femoral single shot block was systematically performed to block the saphenous nerve. The onset times until complete foot block (primary outcome) and the sensory and motor block duration (secondary outcome) were assessed using Wilcoxon test. Values were expressed as medians (1(st)-3(rd) quartile). RESULTS: Except for two delayed sciatic blocks in each group, the onset time otherwise was 35 min (20-60) in Ropi versus 40 min (30-60) in Levo, P = 0.5. Sensory block lasted longer in Levo, 17 h (14-27) compared with 15 h (10-17) in Ropi, P = 0.04. No significant between-group difference was found with motor block durations, 15 h (12-18) in Levo and 15 h (12-16) in Ropi, P = 0.3. CONCLUSION: No difference of onset times was found in ultrasound-guided sciatic block whether using Levo or Ropi. Levo induced a longer-lasting sensory block.

The Script Concordance Test in anesthesiology: Validation of a new tool for assessing clinical reasoning.

OBJECTIVE: To evaluate whether the Script Concordance Test (SCT) can discriminate between levels of experience among anesthesiology residents and attending physicians. STUDY TYPE: Multicenter (Toulouse, Nantes, Bordeaux and Limoges), prospective, observational study. PATIENTS AND METHODS: A SCT made of 60 items was used to evaluate "junior residents" (n=60), "senior residents" (n=47) and expert anesthesiologists (n=10). RESULTS: There were no missing data in our study. Mean scores (±SD) were 69.9 (±6.1), 73.1 (±6.5) and 82.0 (±3.5) out of a potential score of 100 for "junior residents", "senior residents" and expert anesthesiologists, respectively. Results were statistically different between the 3 groups (P=0.001) using the Kruskall-Wallis test. The Cronbach's α score was 0.63. CONCLUSIONS: The SCT is a valid and useful tool for discriminating between anesthesia providers with varying levels of experience in anesthesiology. It may be a useful tool for documenting the progression of reasoning during anesthesia residency.

Inhibition of cytochrome P450 2E1 by propofol in human and porcine liver microsomes.

While almost anesthetics are metabolized by the cytochrome P450 (CYP) 3A4, some major volatile ones such as halothane and sevoflurane are metabolized by CYP2E1 in humans. To determine whether 2,6-diisopropylphenol (propofol), a widely used intravenous anesthetic agent, known to inhibit CYP3A4 and CYP1A2, also inhibits CYP2E1, 6-OH hydroxylation of chlorzoxazone, a prototypical CYP2E1 substrate, was estimated using two pools of human microsomes and one pool of porcine microsomes from seven livers. Basal human enzyme activities were characterized by a V(max) of 1426+/-230 and 288+/-29 pmol min(-1)mg(-1) protein and a K(m) of 122+/-47 and 149+/-42 microM, while the corresponding porcine activities were associated with a V(max) of 352+/-42 pmol min(-1)mg(-1) protein and a K(m) of 167+/-38 microM. A competitive inhibition of CYP2E1 by propofol was observed with low inhibition constants in the therapeutic range in both porcine (19 microM) and human (48 microM) liver microsomes. These in vitro results suggest that propofol could have a protective effect on toxic metabolite activation of compounds catalyzed by CYP2E1.

Plasma volume expansion by medium molecular weight hydroxyethyl starch in neonates: a pilot study.

OBJECTIVE: To study the renal effects (measured by creatininemia) of plasma volume expansion with a medium molecular weight hydroxyethyl starch in the newborn. DESIGN: A prospective, randomized, double-blinded, pilot study. PATIENTS: The study included 26 neonates weighing 690-4030 g (gestational age, 26-40 wks), without cardiac or renal failure or major hemostasis abnormalities and requiring a peripherally inserted central catheter for parenteral nutrition. SETTING: Pediatric and neonatal intensive care unit of a university-affiliated hospital. INTERVENTIONS: Plasma volume expansion was performed to facilitate insertion of the central catheter. After parental consent, neonates were randomly allocated to receive intravenous infusions at 10 mL.kg(-1) of 5% albumin or 6% hydroxyethyl starch 200/0.5. Sample size was calculated to detect an increase in mean creatininemia of >20 micromol.L(-1) (with alpha = 0.05, beta = 0.80). MEASUREMENTS AND MAIN RESULTS: No clinically or statistically significant differences were found between the two groups 6 hrs, 24 hrs, 48 hrs, and 7 days after plasma volume expansion. The study could detect an increase in creatininemia > or =20 micromol.L(-1) with a power of 80%. CONCLUSIONS: In 13 healthy neonates, plasma volume expansion with 10 mL.kg(-1) of 6% hydroxyethyl starch 200/0.5 does not increase creatininemia.

Pulse pressure variations to guide fluid therapy in donors: a multicentric echocardiographic observational study.

PURPOSE: Preload responsiveness parameters could be useful in the hemodynamic management of septic shock. METHODS: A multicentric prospective echocardiographic observational study was conducted from March 2009 to August 2011. Clinically brain-dead subjects were included. Pulse pressure variations (ΔPPs) were recorded. Cardiac index, variation of the maximum flow velocity of aortic systolic blood flow, and right ventricular function parameters were evaluated via transthoracic echocardiography. Fluid responsiveness was defined by at least 15% cardiac index increase, 30 minutes after a 500-mL colloid solution infusion. The number of organs harvested was recorded. RESULTS: Twenty-five subjects were included. Pulse pressure variation could not discriminate responders (n=15) from nonresponders (n=10). The best ΔPP threshold (20%) could discriminate responders with a sensitivity of 100% and a specificity of 40%. Variation of the maximum flow velocity of aortic systolic blood flow, tricuspid annular plane systolic excursion, and right ventricle dilation could not discriminate responders from nonresponders. Eighteen subjects underwent organ harvesting. The number of organs harvested was higher in responders (3.5 [3-5]) than in nonresponders (2.5 [2-3]; P=.03). CONCLUSIONS: A ΔPP threshold of 13% is insufficient to guide volume expansion in donors. The best threshold is 20%. Fluid responsiveness monitoring could enhance organ harvesting.