Influence of the humidification device during acute respiratory distress syndrome.

OBJECTIVE: To evaluate the effects of the humidification device on respiratory, hemodynamic and gas exchange parameters in acute respiratory distress syndrome (ARDS) patients. DESIGN: A prospective open study. SETTING: A medical intensive care unit of a university hospital. PATIENTS: Acute respiratory distress syndrome patients, with hypercapnia (PaCO(2)>60 mmHg). INTERVENTION: A progressive reduction of the humidification system dead space (DSh). The following five conditions were tested sequentially: (1). heat and moisture exchanger (internal volume=95 ml) with a tracheal closed-suction system (internal volume=25 ml; total DSh=120 ml), (2). heat and moisture exchanger (internal volume=45 ml) with the closed-suction system (DSh=70 ml), (3). heat and moisture exchanger (internal volume=25 ml) with the closed-suction system (DSh=50 ml), (4). heated humidifier with the closed-suction system (DSh=25 ml) and (5). heated humidifier alone (DSh=0 ml). Recordings were performed at baseline and every 30 min after each artificial dead-space reduction. All ventilatory settings remained constant during the measurement periods. RESULTS: Ten ARDS patients were included. A significant PaCO(2) decrease was observed at each humidification system dead-space reduction, compared to baseline: PaCO(2 )=80.3+/-20 mmHg at DSh(120) compared to PaCO(2 )=63.6+/-13 mmHg at DSh(0) ( p<0.05). No changes were observed for hemodynamic and ventilatory parameters between the different humidification devices. CONCLUSION: Artificial airway dead-space reduction allows a significant PaCO(2) reduction. Independently of any respiratory mechanical changes, this very simple maneuver may be of importance when low tidal volume ventilation is used in ARDS patients, and when PaCO(2) lowering is warranted.

Noninvasive continuous positive airway pressure ventilation using a new helmet interface: a case-control prospective pilot study.

OBJECTIVE: To evaluate the clinical efficacy of noninvasive continuous positive airway pressure ventilation (CPAP) using a new interface, constituted by a cephalic plastic helmet, in comparison with a standard facial mask. DESIGN AND SETTING: A prospective pilot study with matched-control group, in the emergency department of a teaching hospital. PATIENTS AND METHODS: Eleven consecutive adult patients with acute hypoxemic respiratory failure related to cardiogenic pulmonary edema (whether hypercapnic or not) were enrolled in the study, after failure of the initial medical treatment. Each patient treated with CPAP, using the helmet in addition to a standardized medical treatment, was matched with historical control-patient treated with CPAP using a standard facial mask, and selected by gender, age, and PaCO2 levels on admission. Primary end points were improvements of gas exchanges and clinical parameters of respiratory distress. tolerance was evaluated after each CPAP trial. RESULTS: The 22 patients and controls had similar characteristics at baseline. PaCO2 levels, and clinical parameters improved similarly in both groups. No interface intolerance was reported whether using standard facial mask or the helmet. No complications were observed in either group. The helmet allowed CPAP administration for a longer period of time (p=0.045). In-hospital mortality was not different between the two groups. CONCLUSION: Despite a high dead-space volume (9-15 l), this new helmet interface is an efficient alternative to standard face mask during CPAP, even in cases of severe respiratory acidosis and hypercapnia. It allowed to provide long-duration CPAP, without any adverse events or clinical intolerance.

Statin use does not affect the outcome of acute infection: a prospective cohort study.

UNLABELLED: Statins are used to prevent atherosclerosis because of their hypolipemic effects. In vitro testing and murine models suggest that statins may affect outcome in sepsis. Our meta-analysis of epidemiological studies in humans confirms that previous statin use appears to have a protective effect on infection rates and outcomes. The studies considered, however, were very different and heterogeneity was high, especially for mortality criteria. OBJECTIVE: To compare outcome for current statin users and nonusers hospitalized with fever, under pragmatic circumstances. DESIGN: Prospective cohort study. SETTING: University Hospital of Brest (France). PARTICIPANTS: Febrile (>38 degrees C) patients older than 40 years, admitted to the hospital on an emergency basis in 2005. Patients' outcome was compared according to their exposure to statins (current user or nonuser). MAIN OUTCOME MEASURES: Mortality, length of hospitalization, admission to ICU and to convalescent homes RESULTS: Of 40 343 patients referred for admission by the emergency department in 2005, 964 patients older than 40 years had a fever higher than 38 degrees C and were included in the study. Statin-user status, however, was available for only 921. The ICU admission rate (relative risk: 4.69; 95% CI: 2.42-9.08) was significantly higher (p=0.009) among statin users (n=139) than nonusers (n=782). The groups had similar lengths of hospitalization and similar rates of mortality and of convalescent home admissions. CONCLUSION: Our study does not confirm that statin use affects infection outcome and suggests that previous findings may be associated instead with more cautious care or nonspecific cardiovascular prevention rather than with a specific infection-related effect. Thus, these data support the continuation of statin therapy during physiological aggression, including infection.