[Consequences of mechanical ventilation on diaphragmatic function]. / Conséquences de la ventilation mécanique sur le diaphragme.

INTRODUCTION: Mechanical ventilation is associated with ventilator-induced diaphragmatic dysfunction (VIDD) in animal models and also in humans. BACKGROUND: The main pathophysiological pathways implicated in VIDD seems to be related to muscle inactivity but may also be the consequence of high tidal volumes. Systemic insults from side effects of medication, infection, malnutrition and hypoperfusion also play a part. The diaphragm is caught in the cross-fire of ventilation-induced and systemic-induced dysfunctions. Intracellular consequences of VIDD include oxidative stress, proteolysis, impaired protein synthesis, autophagy activation and excitation-contraction decoupling. VIDD can be diagnosed at the bedside using non-invasive magnetic stimulation of the phrenic nerves which is the gold standard. Other techniques involve patient's participation such as respiratory function tests or ultrasound examination. CONCLUSION AND PERSPECTIVES: At this date, only spontaneous ventilatory cycles and perhaps phrenic nerve stimulation appear to diminish the severity of VIDD in humans but several pathways are currently being examined using animal models. Specific pharmacological options are currently under investigation in animal models.

[Esophageal cancer surgery: evolution of pain management, hemodynamics and ventilation practices during 16 years]. / Œsophagectomie carcinologique : 16ans d'évolution des pratiques anesthésiques ventilatoires, hémodynamiques et analgésiques.

OBJECTIVE: To describe the evolution of perioperative anesthesia practices in for esophageal cancer surgery. PATIENTS AND METHODS: We conducted an observational retrospective study in a single center evaluating main perioperative practices during 16 years (1994-2009). Statistical analysis was done on 4 chronologic quartiles of same sample size. RESULTS: Two hundred and seven consecutive patients were included during the 4 periods 1994-1997 (n=52), 1997-1999 (n=52), 1999-2003 (n=52) and 2004-2009 (n=51). The main significant evolutions between the first and the fourth period were observed: (i) in ventilation: lower tidal volume (9.6[8.6-10.6] vs 7.6[7.0-8.3] mL/kg of ideal body weight (IBW), p<0.01), increased use of Positive End Expiratory Pressure (0 vs 83%, p<0.001) and increased use of post-operative non-invasive ventilation (0 vs 51%, p<0.001); (ii) in hemodynamic management: lower fluid replacement (20.6 [16.0-24.6] vs 12.6 [9.7-16.2] mL/h/kg of IBW, p<0.001); (iii) in analgesia: increased use of epidural thoracic anesthesia (31 vs 57%, p<0.001). Peroperative bleeding, type of fluid replacement, length of mechanical ventilation, length of stay in intensive care unit, ventilatory free days and mortality at day 28 didn't change. CONCLUSIONS: During these previous years, anesthesia practices in ventilation, hemodynamics and analgesia for esophageal cancer surgery have changed.

[Risk of barotrauma when using non-reinhalation Waters valves: a comparative study on bench test]. / Risque barotraumatique avec des valves de non-réinhalation de Waters: étude comparative sur banc d'essai.

OBJECTIVE: Manual ventilation is delivered in the operating room or the intensive care unit to intubated or non-intubated patients, using non-rebreathing systems such as the Waters valve. New generation Waters valves are progressively replacing the historic Waters valve. The aim of this study was to evaluate maximal pressure delivered by these 2 valves. TYPE OF STUDY: Bench test. MATERIAL AND METHOD: Thirty-two different conditions were tested, according to 2 oxygen flow rates (10 and 20L/min), without (static condition) or with manual insufflations (dynamic condition) and 4 valve expiratory opening pressures. The primary endpoint was maximal pressure measured at the exit of the valve, connected to a model lung and a bench test. RESULTS: Measured pressures were different for most evaluated conditions. Increasing oxygen flow from 10 to 20L/min increased maximal pressure for both valves. Increasing valve expiratory opening pressure induced a significant increase in maximal pressure for the new generation valve (from 4 to 61cmH2O in static conditions and from 18 to 68cmH2O in dynamic conditions). For the historic valve, maximal pressure increased significantly but remained below 15cmH2O in both static and dynamic conditions. CONCLUSION: Use of new generation Waters valves should be different from historic Waters valves. Indeed, barotrauma could be caused by badly adapted valve expiratory opening pressure settings.

[Antifungal treatments of candidemia in non-neutropenic patients: evaluation of practice in intensive care units]. / Traitements antifongiques des candidémies chez les patients non neutropéniques : évaluation des pratiques en réanimation.

OBJECTIVE: The authors had for objective to assess systemic antifungal treatment for candidemia in non-neutropenic patients, in intensive care units (ICU), and compare the results with French 2004 recommendations. STUDY DESIGN: A retrospective multicenter study (nine ICU in two teaching hospitals) was made. PATIENTS AND METHOD: Thirty-eight non-neutropenic patients with at least one positive blood culture for Candida who had received systemic antifungal treatment were included between May 2004 and September 2007. RESULTS: Thirty-nine cases of candidemia were analyzed. The median age was 54.5 (21-80), the median SAPS II score at admission was 44 (20-79), the median duration of stay in ICU was 22.5 days (2-82), and the death rate was 45%. Candida albicans was identified in 69% of the cases. Eight percent of Candida sp. isolates were resistant or susceptible dose-dependent (S-DD) to fluconazole. Before identification, fluconazole, caspofungin, voriconazole, and amphotericin B were used in 74%, 15%, 5%, and 5% of cases respectively. After identification and antifungal susceptibility determination, fluconazole was used in 68% of cases, caspofungin in 24% of cases, any formulation of amphotericin B in 6% of cases, voriconazole in 3% of cases. The French recommendations were applied in 71% of cases before identification and in 68% of cases after identification and antifungal susceptibility determination. CONCLUSION: The main causes of non-compliance to recommendations were the use of fluconazole in patients previously exposed to azole agents, the use of caspofungin in hemodynamically unstable patients, and the absence of therapeutic desescalade.

[ARDS and influenza A (H1N1): patients' characteristics and management in intensive care unit. A literature review]. / Grippe A (H1N1) et SDRA: caractéristiques des patients admis en réanimation et prise en charge. Revue de la littérature.

Novel influenza A (H1N1) at the origin of the 2009 pandemic flu developed mainly in subjects of less than 65 years contrary to the seasonal influenza, which usually developed in elderly patients of more than 65 years. Elderly subjects are partly protected by old meetings with close stocks. Influenza A(H1N1) can arise in serious forms within 60 to 80% of cases a fulminant acute respiratory distress syndrome (ARDS) "malignant and fulminant influenza" in subjects without any comorbidity, which makes the gravity and the fear of this influenza. The fact that this influenza A (H1N1) can develop in healthy young patients and evolve in few hours to a severe ARDS with a refractory hypoxemia gave to the foreground the possible interest of the recourse to extracorporeal oxygenation (ECMO) in some selected severe ARDS (5-10%). The first publications of patients admitted in intensive care unit (ICU) for severe influenza A (H1N1) often associated to an ARDS reported a mortality rate from 15 to 40%. This mortality variability may be explained in part by different studied populations, ARDS characteristics and human and material resources in the ICUs between the countries. Indeed, the highest mortality rates (30-40%) have been reported by in Mexico which were affected the first by pandemic flu and which were not prepared. A bacterial pneumonia was associated to H1N1 influenza in approximately 30% of the cases as at admission in ICU or following the days of the admission justifying an early antibiotherapy associated to the antiviral treatment by oseltamivir (Tamiflu). Obesity, pregnancy and respiratory diseases (asthma, COPD) seem to be associated to the development of a severe viral pneumonia due to influenza A (H1N1) often with ARDS. Older age, high APACHE II and SOFA scores and a delay of initiation of the antiviral treatment by oseltamivir are associated to higher morbidity and mortality. Other analyses of the results obtained from the first published papers included more patients and future studies would permitted to better define the role of therapeutics such as steroids and ECMO.