Prevalence of anxiety and depressive symptoms among medical residents in Tunisia: a cross-sectional survey.

OBJECTIVE: To assess the prevalence of anxiety and depressive symptoms and the associated risk factors among Tunisian medical residents. DESIGN: Cross-sectional survey. SETTING: Faculty of Medicine, Tunis. PARTICIPANTS: All Tunisian medical residents brought together between 14 and 22 December 2015 to choose their next 6-month rotation. INTERVENTION: The items of the Hospital Anxiety and Depression (HAD) questionnaire were employed to capture the prevalence of anxiety and/or depression among the residents. The statistical relationships between anxiety and depression (HAD score) and sociodemographic and work-related data were explored by Poisson regression. RESULTS: 1700 out of 2200 (77%) medical residents (mean age: 28.5±2 years, female: 60.8%) answered the questionnaire. The mean working hours per week was 62±21 hours; 73% ensured a mean of 5.4±3 night shifts per month; and only 8% of them could benefit from a day of safety rest. Overall, 74.1% of the participating residents had either definite (43.6%) or probable (30.5%) anxiety, while 62% had definite (30.5%) or probable (31.5%) depression symptoms, with 20% having both definite anxiety and definite depression. The total HAD score was significantly associated with the resident's age (OR=1.014, 95% CI 1.006 to 1.023, p=0.001); female gender (OR=1.114, 95% CI 1.083 to 1.145, p<0.0001); and the heavy burden of work imposed on a weekly or monthly basis, as reflected by the number of night shifts per month (OR=1.048, 95% CI 1.016 to 1.082, p=0.03) and the number of hours worked per week (OR=1.008, 95% CI 1.005 to 1.011, p<0.0001). Compared with medical specialties, the generally accepted difficult specialties (surgical or medical-surgical) were associated with a higher HAD score (OR=1.459, 95% CI 1.172 to 1.816, p=0.001). CONCLUSION: Tunisian residents experience a rate of anxiety/depression substantially higher than that reported at the international level. This phenomenon is worrying as it has been associated with an increase in medical errors, work dissatisfaction and attrition. The means of improving the well-being of Tunisian medical residents are explored, emphasising those requiring immediate implementation.

Noninvasive ventilation with helium-oxygen mixture in hypercapnic COPD exacerbation: aggregate meta-analysis of randomized controlled trials.

When used as a driving gas during NIV in hypercapnic COPD exacerbation, a helium-oxygen (He/O2) mixture reduces the work of breathing and gas trapping. The potential for He/O2 to reduce the rate of NIV failure leading to intubation and invasive mechanical ventilation has been evaluated in several RCTs. The goal of this meta-analysis is to assess the effect of NIV driven by He/O2 compared to air/O2 on patient-centered outcomes in hypercapnic COPD exacerbation. Relevant RCTs were searched using standard procedures. The main endpoint was the rate of NIV failure. The effect size was computed by a fixed-effect model, and estimated as odds ratio (OR) with 95% confidence interval (CI). Additional endpoints were ICU mortality, NIV-related side effects, and the length and costs of ICU stay. Three RCTs fulfilled the selection criteria and enrolled a total of 772 patients (386 patients received He/O2 and 386 received air/O2). Pooled analysis showed no difference in the rate of NIV failure when using He/O2 mixture compared to air/O2: 17 vs 19.7%, respectively; OR 0.84, 95% CI 0.58-1.22; p = 0.36; I 2 for heterogeneity = 0%, and no publication bias. ICU mortality was also not different: OR 0.8, 95% CI 0.45-1.4; p = 0.43; I 2 = 5%. However, He/O2 was associated with less NIV-related adverse events (OR 0.56, 95% CI 0.4-0.8, p = 0.001), and a shorter length of ICU stay (difference in means = -1.07 day, 95% CI -2.14 to -0.004, p = 0.049). Total hospital costs entailed by hospital stay and NIV gas were not different: difference in means = -279$, 95% CI -2052-1493, p = 0.76. Compared to air/O2, He/O2 does not reduce the rate of NIV failure in hypercapnic COPD exacerbation. It is, however, associated with a lower incidence of NIV-related adverse events and a shortening of ICU length of stay with no increase in hospital costs.

Trends in use and impact on outcome of empiric antibiotic therapy and non-invasive ventilation in COPD patients with acute exacerbation.

BACKGROUND: Empiric antibiotic therapy is routinely prescribed in patients with acute COPD exacerbations (AECOPD) requiring ventilatory support on the basis of studies including patients conventionally ventilated. Whether this practice remains valid to current management with first-line non-invasive ventilation (NIV) is unclear. METHODS: In a cohort of ICU patients admitted between 2000 and 2012 for AECOPD, we analyzed the trends in empiric antibiotic therapy and in primary ventilatory support strategy, and their respective impact on patients' outcome. RESULTS: 440 patients admitted for 552 episodes were included; primary NIV use increased from 29 to 96.7 % (p < 0.001), whereas NIV failure rate decreased significantly (p = 0.004). In parallel, ventilator-associated pneumonia (VAP) rate, VAP density and empiric antibiotic therapy use decreased (p = 0.037, p = 0.002, and p < 0.001, respectively). These figures were associated with a trend toward lower ICU mortality rate (p = 0.058). Logistic regression showed that primary NIV use per se was protective against fatal outcome [odds ratios (OR) = 0.08, 95 %CI 0.03-0.22; p < 0.001], whereas NIV failure, VAP occurrence, and cardiovascular comorbidities were associated with increased ICU mortality [OR = 17.6 (95 %CI 5.29-58.93), 11.5 (95 %CI 5.17-25.45), and 3 (95 %CI 1.37-6.63), respectively]. Empiric antibiotic therapy was associated with decreased VAP rate (log rank; p < 0.001), but had no effect on mortality (log rank; p = 0.793). CONCLUSIONS: The sustained increase in NIV use allowed a decrease in empiric antibiotic prescriptions in AECOPD requiring ventilatory support. Primary NIV use and its success, but not empiric antibiotic therapy, were associated with a favorable impact on patients' outcome.

Study of severe scorpion envenoming following subcutaneous venom injection into dogs: Hemodynamic and concentration/effect analysis.

To evaluate the dose-effects of Androctonus australis hector (Aah) venom injected subcutaneously on hemodynamics and neurohormonal secretions, 10 anesthetized and ventilated mongrel dogs, were split in two groups (n = 5/group). Subcutaneous injection was done with either 0.2 mg/kg or 0.125 mg/kg of the purified G50 scorpion toxic fraction. Hemodynamic parameters using right heart catheter were recorded and plasma concentrations of catecholamine, troponin, and serum toxic fraction were measured sequentially from baseline to 120 min. We identified the dose of toxic fraction evoking characteristic hemodynamic perturbation of severe envenomation, the time-lapse to envenomation, and the associated plasma level. The injection of 0.125 mg/kg toxic fraction was not associated with significant variations in hemodynamic parameters, whereas the 0.2 mg/kg dose caused envenomation characterized by significant increase in plasma catecholamines, increased pulmonary artery occluded pressure, mean arterial pressure, and systemic vascular resistance (p < 0.05), in association with sustained decline in cardiac output (p < 0.001). Envenomation occurred by the 30th minute, and the corresponding concentration of toxic fraction was 1.14 ng/ml. The current experiment allowed the identification of the sub-lethal dose (0.2 mg/kg) of the toxic fraction of Aah administered by the subcutaneous route. Two parameters with potential clinical relevance were also uncovered: the time-lapse to envenomation and the corresponding concentration of toxic fraction.

Scorpion-related cardiomyopathy: Clinical characteristics, pathophysiology, and treatment.

CONTEXT: Scorpion envenomation is a threat to more than 2 billion people worldwide with an annual sting number exceeding one million. Acute heart failure presenting as cardiogenic shock or pulmonary edema, or both is the most severe presentation of scorpion envenomation accounting for 0.27% lethality rate. OBJECTIVE: The purpose of this review is to characterize the scorpion-related cardiomyopathy, clarify its pathophysiological mechanisms, and describe potentially useful treatments in this particular context. METHODS: We searched major databases on observational or interventional studies (whether clinical or experimental) on the cardiorespiratory consequences of scorpion envenomation and their treatment. No limit of age or language was imposed. A critical appraisal of the literature was conducted in order to provide a pathophysiological scheme that reconciles reported patterns of cardiovascular toxicity and hypotheses and assumptions made so far. RESULTS: Early cardiovascular dysfunction is related to the so-called "vascular phase" of scorpion envenomation, which is related to a profound catecholamine-related vasoconstriction leading to a sharp increase in left ventricular (LV) afterload, thereby impeding LV emptying, and increasing LV filling pressure. Following this vascular phase, a myocardial phase occurs, characterized by a striking alteration in LV contractility (myocardial stunning), low cardiac output, and hypotensive state. The right ventricle involvement is symmetric to that of LV with a profound and reversible alteration in right ventricular performance. This phase is unique in that it is reversible spontaneously or under inotropic treatment. Scorpion myocardiopathy combines the features of takotsubo myocardiopathy (or stress myocardiopathy) which is linked to a massive release in catecholamines leading to myocardial ischemia through coronary vasomotor abnormalities (epicardial coronary spasm and/or increase in coronary microvascular resistance). Treatment of pulmonary edema due to scorpion envenomation follows the same principles as those applied for the treatment of cardiogenic pulmonary edema in general: this begins with oxygen supplementation targeting an oxygen saturation of 92% or more, by oxygen mask, continuous positive airway pressure, noninvasive ventilation, or conventional mechanical ventilation. Dobutamine effectively improves hemodynamic parameters and may reduce mortality in severe scorpion envenomation. CONCLUSION: Scorpion cardiomyopathy is characterized by a marked and reversible alteration in biventricular performance. Supportive treatment relying on ventilatory support and dobutamine infusion is a bridge toward recovery in the majority of patients.

Family cluster of Middle East respiratory syndrome coronavirus infections, Tunisia, 2013.

In 2013 in Tunisia, 3 persons in 1 family were infected with Middle East respiratory syndrome coronavirus (MERS-CoV). The index case-patient's respiratory tract samples were negative for MERS-CoV by reverse transcription PCR, but diagnosis was retrospectively confirmed by PCR of serum. Sequences clustered with those from Saudi Arabia and United Arab Emirates.

Systemic corticosteroids in acute exacerbation of COPD: a meta-analysis of controlled studies with emphasis on ICU patients.

Guidelines on systemic corticosteroids in chronic obstructive pulmonary disease (COPD) exacerbation rely on studies that excluded patients requiring ventilatory support. Recent publication of studies including ICU patients allows estimation of the level of evidence overall and in patients admitted to the ICU. We included RCTs evaluating the efficacy and safety of systemic corticosteroids in COPD exacerbation, compared to placebo or standard treatment. The effect size on treatment success was computed by a random effects model overall and in subgroups of non-ICU and ICU patients. Effects on mortality and on the rate of adverse effects of corticosteroids were also computed. Twelve RCTs (including 1,331 patients) were included. Pooled analysis showed a statistically significant increase in the treatment success rate when using systemic corticosteroids: odds ratio (OR) = 1.72, 95% confidence interval (CI) = 1.15 to 2.57; p = 0.01. Subgroup analysis showed different patterns of effect in ICU and non-ICU subpopulations: a non-significant difference of effect in the subgroup of ICU patients (OR = 1.34, 95% CI = 0.61 to 2.95; p = 0.46), whereas in the non-ICU patients, the effect was significant (OR = 1.87, 95% CI = 1.18 to 2.99; p = 0.01; p for interaction = 0.72). Among ICU patients, there was no difference in the success whether patients were ventilated with tracheal intubation (OR = 1.85, 95% CI = 0.14 to 23.34; p = 0.63) or with non-invasive ventilation (OR = 4.88, 95% CI = 0.31 to 75.81; p = 0.25). Overall, there was no difference in the mortality rate between the steroid-treated group and controls: OR = 1.07, 95% CI = 0.67 to 1.71; p = 0.77. The rate of adverse events increased significantly with corticosteroid administration (OR = 2.36, 95% CI = 1.67 to 3.33; p < 0.0001). In particular, treatment with systemic corticosteroids significantly increased the risk of hyperglycemic episodes requiring initiation or alteration of insulin therapy (OR = 2.96, 95% CI = 1.69 to 5; p < 0.0001). We found corticosteroids to be beneficial in the whole population (non-critically ill and critically ill patients) in terms of treatment success rate. However, subgroup analysis showed that this effect of corticosteroids was only observed in non-critically ill patients whereas critically ill patients derived no benefit from systemic corticosteroids regardless of the chosen ventilatory mode (invasive or non-invasive ventilation). Further analyses showed no effect on mortality of corticosteroids, but higher side effects, such as hyperglycemic episodes requiring the initiation or alteration of insulin therapy.

Prednisone in COPD exacerbation requiring ventilatory support: an open-label randomised evaluation.

Recommendation of the use of systemic steroids in chronic obstructive disease (COPD) exacerbation rely on trials that excluded patients requiring ventilatory support. In an open-label, randomised evaluation of oral prednisone administration, 217 patients with acute COPD exacerbation requiring ventilatory support were randomised (with stratification on the type of ventilation) to usual care (n=106) or to receive a daily dose of prednisone (1 mg·kg(-1)) for up to 10 days (n=111). There was no difference regarding the primary end-point, intensive care unit mortality, which was 17 (15.3%) deaths versus 15 (14%) deaths in the steroid-treated and control groups, respectively (relative risk 1.08, 95% CI 0.6-2.05). Analysis according to ventilation modalities showed similar mortality rates. Noninvasive ventilation failed in 15.7% and 12.7% (relative risk 1.25, 95% CI 0.56-2.8; p=0.59), respectively. Both study groups had similar median mechanical ventilation duration and intensive care unit length of stay, which were 6 (interquartile range 6-12) days versus 6 (3.8-12) days and 9 (6-14) days versus 8 (6-14) days, respectively. Hyperglycaemic episodes requiring initiation or alteration of current insulin doses occurred in 55 (49.5%) patients versus 35 (33%) patients in the prednisone and control groups, respectively (relative risk 1.5, 95% CI 1.08-2.08; p=0.015). Prednisone did not improve intensive care unit mortality or patient-centred outcomes in the selected subgroup of COPD patients with severe exacerbation but significantly increased the risk of hyperglycaemia.

NT-proBNP levels at spontaneous breathing trial help in the prediction of post-extubation respiratory distress.

PURPOSE: To evaluate and compare the performance of NT-proBNP levels, plasma protein concentration, hematocrit, and fluid balance for the preceding 24 h in predicting the outcome of the two steps of weaning: (1) spontaneous breathing trial (SBT), (2) extubation. METHODS: This was a prospective observational study of 143 patients who were mechanically ventilated for more than 48 h (55% COPD) and were ready to wean. They underwent an SBT and were extubated when they passed the trial. Immediately before the SBT, we measured the evaluated diagnosis tools. RESULTS: Of 143 patients, 80 (56%) passed the SBT and were extubated. Of these, two were reintubated for laryngeal dyspnea, 57 had no respiratory problem during the next 48 h, and 21 developed post-extubation respiratory distress (26%). Rescue noninvasive ventilation (NIV) prevented reintubation in 15 (71%). None of the tested diagnosis tools predicted the outcome of the SBT. Patients who developed post-extubation respiratory distress were older, had lower values of plasma protein concentration and higher values of NT-proBNP than those who did not. Only NT-proBNP was an independent predictor of the occurrence of post-extubation respiratory distress (OR 1.2; 95% CI 1.09-1.4; p = 0.003); the area under the ROC curve for NT-proBNP to predict post-extubation respiratory distress was 0.78 (95% CI 0.67-0.89; p = 0.0001). NT-proBNP was more accurate to rule out (negative likelihood ratio 0.09 for a cutoff of no greater than 1,000 pg/ml) than to rule in the risk of post-extubation respiratory distress (positive likelihood ratio 3.45 for a cutoff of at least 2,000 pg/ml). CONCLUSION: NT-proBNP levels at SBT help in the prediction of post-extubation respiratory distress and could identify the subgroup of extubated patients requiring close observation and/or prophylactic NIV.

N-terminal proB-type natriuretic peptide levels aid the diagnosis of left ventricular dysfunction in patients with severe acute exacerbations of chronic obstructive pulmonary disease and renal dysfunction.

BACKGROUND AND OBJECTIVE: The aim of this study was to assess the performance of N-terminal proB-type natriuretic peptide (NT-proBNP) levels for the diagnosis of left ventricular dysfunction in patients with severe acute exacerbations of chronic obstructive pulmonary disease (COPD) and renal dysfunction. METHODS: NT-proBNP levels at admission were measured in consecutive patients admitted to two participating intensive care units with acute exacerbations of COPD. Left ventricular dysfunction was assessed on the basis of clinical and echocardiographic criteria. The performance of NT-proBNP levels was evaluated in patients with or without renal dysfunction. RESULTS: Among the 120 patients included in the study, 70 had impaired renal function, defined as a glomerular filtration rate of <90 mL/min/1.73 m(2). NT-proBNP levels were inversely correlated with glomerular filtration rate (Spearman's correlation coefficient = -0.457, P < 0.001). Overall, left ventricular dysfunction was diagnosed in 58 patients (48.3%). Median NT-proBNP levels were significantly higher in these patients, irrespective of whether their renal function was normal (3313 (interquartile range (IQR) 4603) vs 337 (IQR 695) pg/mL, P < 0.001) or impaired (5692 (IQR 10714) vs 887 (IQR 1165) pg/mL, P < 0.001). The areas under the receiver operating characteristic curves were 0.87 and 0.78, respectively. The threshold NT-proBNP value with the highest diagnostic accuracy was greater in the setting of renal dysfunction (2000 pg/mL; sensitivity 71%, specificity 82%, compared with 1000 pg/mL in patients with normal renal function; sensitivity 94%, specificity 82%). Multivariate analysis showed that left ventricular dysfunction and glomerular filtration rate were independently associated with elevated NT-proBNP levels. CONCLUSIONS: NT-proBNP remains an accurate biomarker for the diagnosis of left ventricular dysfunction associated with acute exacerbations of COPD. Threshold values of NT-proBNP were higher in patients with impaired renal function than in those with normal renal function.

Pattern of end-of-life decisions in two Tunisian intensive care units: the role of culture and intensivists' training.

PURPOSE: End-of-life (EOL) decisions are not well studied in developing countries. We report EOL decision patterns in two Tunisian intensive care units [ICUs, medical (MICU) and surgical (SICU)] belonging to the same teaching hospital. METHODS: Consecutive deaths that occurred in participating ICUs over 2 years were analysed. End-of-life decisions were prospectively recorded by the senior attending physicians, while subject's characteristics were retrospectively collected. RESULTS: Deaths occurred in 326 of 1,733 ICU-admitted patients (median age: 64 years; median SAPS II at admission = 36). Overall, a decision for full support was taken in 69%, while decisions to withhold or withdraw life support were held in 22.1 and 8.9% of deaths, respectively. The rate of end-of-life decisions was similar in the MICU and the SICU. In no instance was there MV withdrawal during ICU stay. Discharging patients to die at home was observed only in the MICU (10 out of the 20 patients with a withdrawal decision). Two factors were independently associated with WH or WD decisions: a severe and ultimately fatal underlying disease was positively associated with such decisions (OR = 2.4, 95% CI: 1.3-4.36; p = 0.003), while having an independent functional status before the ICU was associated with a decreased rate of physician decisions of WH or WD (OR = 0.32, 95% CI: 0.15-0.67; p = 0.002). CONCLUSION: Withholding and withdrawing life support are common in medical and surgical ICUs of a Tunisian hospital. Withholding is more frequent than withdrawing life support. These decisions appear to be effected by functional status and underlying conditions.

Meta-analysis of controlled studies on immunotherapy in severe scorpion envenomation.

BACKGROUND: Despite conflicting evidence, specific serotherapy is recommended for scorpion envenomation. METHODS: A meta-analysis of prospective or observational controlled studies, comparing intravenous scorpion antivenin (SAV) with control, was performed. Binary outcomes are reported as risk difference for clinical improvement and mortality rates. Analysis was performed both for the whole number of included studies and for two subgroups (set up according to the geographic origin of scorpions). RESULTS: Nine studies (four randomised controlled trials (RCTs), five observational) enrolling 687 patients were identified. Six dealt with Old World scorpions and three originated from Arizona. Overall, the rate of clinical improvement was similar in SAV treated and untreated patients (risk difference=0.22, 95% CI -0.35 to 0.79; p=0.45 for effect). Subgroup analysis showed favourable effects of SAV in the Arizona scorpion envenomation (risk difference=0.53; 95% CI 0.16 to 0.91; p<0.001), and non-significant unfavourable effects in Old World scorpion envenomation (risk difference=-0.05; 95% CI -0.28 to 0.18; p=0.65; p=0.003 for z-value, indicating a true heterogeneity of treatment effects). In Old World scorpion envenomation, there was no statistical difference in the risk of death in SAV treated and untreated scorpion envenomated patients (risk difference=0.007, 95% CI -0.02 to 0.03; p=0.6 for effect). Overall, administration of scorpion antivenin was associated with a reduction by 13 h in the mean time of symptom resolution (95% CI -17 to -9; p<0.0001). Serious adverse events were reported at a rate of 1-2% while minor adverse events occurred in up to 40% of patients. CONCLUSIONS: SAV should not be administered in Old World scorpion envenomation until its efficacy is established by an appropriately designed RCT. In the Arizona scorpion sting, SAV hastens the recovery process.

An updated study-level meta-analysis of randomised controlled trials on proning in ARDS and acute lung injury.

INTRODUCTION: In patients with acute lung injury (ALI) and/or acute respiratory distress syndrome (ARDS), recent randomised controlled trials (RCTs) showed a consistent trend of mortality reduction with prone ventilation. We updated a meta-analysis on this topic. METHODS: RCTs that compared ventilation of adult patients with ALI/ARDS in prone versus supine position were included in this study-level meta-analysis. Analysis was made by a random-effects model. The effect size on intensive care unit (ICU) mortality was computed in the overall included studies and in two subgroups of studies: those that included all ALI or hypoxemic patients, and those that restricted inclusion to only ARDS patients. A relationship between studies' effect size and daily prone duration was sought with meta-regression. We also computed the effects of prone positioning on major adverse airway complications. RESULTS: Seven RCTs (including 1,675 adult patients, of whom 862 were ventilated in the prone position) were included. The four most recent trials included only ARDS patients, and also applied the longest proning durations and used lung-protective ventilation. The effects of prone positioning differed according to the type of study. Overall, prone ventilation did not reduce ICU mortality (odds ratio = 0.91, 95% confidence interval = 0.75 to 1.2; P = 0.39), but it significantly reduced the ICU mortality in the four recent studies that enrolled only patients with ARDS (odds ratio = 0.71; 95% confidence interval = 0.5 to 0.99; P = 0.048; number needed to treat = 11). Meta-regression on all studies disclosed only a trend to explain effect variation by prone duration (P = 0.06). Prone positioning was not associated with a statistical increase in major airway complications. CONCLUSIONS: Long duration of ventilation in prone position significantly reduces ICU mortality when only ARDS patients are considered.

Weaning difficult-to-wean chronic obstructive pulmonary disease patients: a pilot study comparing initial hemodynamic effects of levosimendan and dobutamine.

PURPOSE: To compare the short-term hemodynamic effects of levosimendan and dobutamine in chronic obstructive pulmonary disease (COPD) patients experiencing weaning difficulties in relation with increased left ventricular filling pressure. MATERIALS AND METHODS: This prospective, sequential, pilot study included 10 COPD patients experiencing weaning difficulties in relation with increased left ventricular filling pressure ascertained by an increase >10 mm Hg of pulmonary artery occlusion pressure (PAOP) at the shift from mechanical to spontaneous breathing (SB). Patients received 1 h infusion of 7 µg/kg per minute of dobutamine, followed by 24-hour infusion of 0.2 µg/kg per minute levosimendan. Hemodynamic variables were measured under MV and 15 to 30 minutes after SB at baseline, at the end of dobutamine infusion, at a washout period, and after levosimendan infusion. RESULTS: At baseline, the shift from mechanical ventilation to spontaneous ventilation was associated with a significant increase in PAOP from a median of 15 (interquartile range [IQR], 6) to 29 (9) mm Hg. Both drugs reduced significantly the level of PAOP increase at SB, but levosimendan had a greater effect than dobutamine [median PAOP increase (IQR): 5 (2) vs 9 (4) mm Hg, respectively; P < .01]. CONCLUSIONS: Both drugs reduced the magnitude of PAOP increase at SB in difficult-to-wean COPD patients. PAOP increase was reduced to a greater extent by levosimendan.

Impact of energy deficit calculated by a predictive method on outcome in medical patients requiring prolonged acute mechanical ventilation.

To assess energy balance in very sick medical patients requiring prolonged acute mechanical ventilation and its possible impact on outcome, we conducted an observational study of the first 14 d of intensive care unit (ICU) stay in thirty-eight consecutive adult patients intubated at least 7 d. Exclusive enteral nutrition (EN) was started within 24 h of ICU admission and progressively increased, in absence of gastrointestinal intolerance, to the recommended energy of 125.5 kJ/kg per d. Calculated energy balance was defined as energy delivered - resting energy expenditure estimated by a predictive method based on static and dynamic biometric parameters. Mean energy balance was - 5439 (sem 222) kJ per d. EN was interrupted 23 % of the time and situations limiting feeding administration reached 64 % of survey time. ICU mortality was 72 %. Non-survivors had higher mean energy deficit than ICU survivors (P = 0.004). Multivariate analysis identified mean energy deficit as independently associated with ICU death (P = 0.02). Higher ICU mortality was observed with higher energy deficit (P = 0.003 comparing quartiles). Using receiver operating characteristic curve analysis, the best deficit threshold for predicting ICU mortality was 5021 kJ per d. Kaplan-Meier analysis showed that patients with mean energy deficit > or =5021 kJ per d had a higher ICU mortality rate than patients with lower mean energy deficit after the 14th ICU day (P = 0.01). The study suggests that large negative energy balance seems to be an independent determinant of ICU mortality in a very sick medical population requiring prolonged acute mechanical ventilation, especially when energy deficit exceeds 5021 kJ per d.

Interface strategy during noninvasive positive pressure ventilation for hypercapnic acute respiratory failure.

OBJECTIVE: To assess the influence of initial mask choice on the clinical effectiveness and tolerance of noninvasive positive pressure ventilation (NIPPV) in the management of hypercapnic acute respiratory failure. DESIGN: A prospective randomized controlled clinical study. SETTING: A medical intensive care unit at a university hospital. INTERVENTION: Randomization between two NIPPV interfaces. PATIENTS: Initial mask choice was randomized between two standard masks: face (NIPPVf group) and nasal (NIPPVn group). The main end point was mask failure (i.e., mask change and/or intubation). Secondary end points were tolerance of NIPPV, change in respiratory parameters during the first 3 days, and patient outcome. Results were analyzed on an intent to treat basis. A per protocol analysis was also conducted. MAIN RESULTS: Ninety patients with underlying chronic lung disease were included, 46 in the NIPPVf group and 44 in the NIPPVn group. The overall success rate of NIPPV was 83%. Mask failure occurred significantly more often in the NIPPVn group (32/44 vs. 9/46; p < 0.0001), mainly because of the need for mask change (32/44 vs. 0/46; p < 0.0001) because of the occurrence of major buccal air-leaks in 94% of cases. Improvement in respiratory parameters was similar in the two groups. Whereas air-leaks were more frequent in the NIPPVn group (p < 0.05), respiratory comfort was assessed as lower and complications more frequent by the staff in the NIPPVf group from day 2 (p < 0.05). CONCLUSIONS: A face mask should be the first-line strategy in the initial management of hypercapnic acute respiratory failure with NIPPV. However, if NIPPV has to be prolonged, switching to a nasal mask may improve comfort by reducing face mask complications.