Continuous positive airway pressure vs. proportional assist ventilation for noninvasive ventilation in acute cardiogenic pulmonary edema.

OBJECTIVE: To compare continuous positive airway pressure (CPAP) and proportional assist ventilation (PAV) as modes of noninvasive ventilatory support in patients with severe cardiogenic pulmonary edema. DESIGN AND SETTING: A prospective multicenter randomized study in the medical ICUs of three teaching hospitals. PATIENTS: Thirty-six adult patients with cardiogenic pulmonary edema (CPA) with unresolving dyspnea, respiratory rate above 30/min and/or SpO2 above 90% with O2 higher than 10 l/min despite conventional therapy with furosemide and nitrates. INTERVENTIONS: Patients were randomized to undergo either CPAP (with PEEP 10 cmH2O) or PAV (with PEEP 5-6 cmH2O) noninvasive ventilation through a full face mask and the same ventilator. MEASUREMENTS AND RESULTS: The main outcome measure was the failure rate as defined by the onset of predefined intubation criteria, severe arrythmias or patient's refusal. On inclusion CPAP (n=19) and PAV (n=17) groups were similar with regard to age, sex ratio, type of heart disease, SAPS II, physiological parameters (mean arterial pressure, heart rate, blood gases), amount of infused nitrates and furosemide. Failure was observed in 7 (37%) CPAP and 7 (41%) PAV patients. Among these, 4 (21%) CPAP and 5 (29%) PAV patients required endotracheal intubation. Changes in physiological parameters were similar in the two groups. Myocardial infarction and ICU mortality rates were strictly similar in the two groups. CONCLUSIONS: In the present study PAV was not superior to CPAP for noninvasive ventilation in severe cardiogenic pulmonary edema with regard to either efficacy and tolerance.

Cardiovascular response to dopamine and early prediction of outcome in septic shock: a prospective multiple-center study.

OBJECTIVES: To compare mortality rates between dopamine-sensitive (Dopa-S) and dopamine-resistant (Dopa-R) septic shock patients, the latter group defined by a mean arterial pressure <70 mm Hg despite the use of 20 mug/kg/min dopamine. DESIGN: A human, prospective observational, multiple-center, clinical trial. SETTING: Ten intensive care units from ten hospitals. PATIENTS: 110 patients with septic shocks. INTERVENTIONS: Following volume resuscitation, patients were treated by a rapid increase in dopamine infusion from 10 to 20 mug/kg/min. If mean arterial pressure remained <70 mm Hg, dopamine treatment was promptly switched to norepinephrine or epinephrine. MEASUREMENTS AND MAIN RESULTS: Dopamine sensitivity, arterial gas, lactate, and organ system failure scores were measured at admission and after 6, 12, 24, 48, 72, 96, and 120 hrs. The overall 28-day mortality rate was 54% for the entire population under study. In multivariate analysis, independent predictors of death were dopamine resistance (odds ratio, 9.5; 95% confidence interval, 3-25), arterial lactate >3.5 mmol/L (odds ratio, 1.75; 95% confidence interval, 1.06-2.55), and Sepsis-related Organ Failure Assessment score >10 (odds ratio, 1.40; 95% confidence interval, 1.07-2.12). Of the 110 patients studied, 66 were observed to be resistant to dopamine (60%). In the Dopa-S group, the 28-day mortality rate was 16% (seven of 44 patients) compared with 78% (52 of 66 patients) in the Dopa-R group (p = .0006). The capacity of dopamine resistance to predict death was associated with a sensitivity of 84% and a specificity of 74%. At 24 hrs, the association of dopamine resistance to a lactate level >3.5 mmol/L improved the prognostic value (sensitivity, 90%, specificity, 92%). CONCLUSIONS: Dopamine sensitivity is associated with decreased mortality rate. Early recognition of dopamine resistant septic shock could allow for better screening of patients with an ominous prognosis.