Combination of clonidine sedation and spontaneous breathing-pressure support upon acute respiratory distress syndrome: a feasibility study in four patients

INTRODUCTION

As alpha-2 agonists preserve ventilator drive, patients presenting with acute respiratory distress syndrome (ARDS, Pa02/FiO2 < 200) were managed using sedation with an alpha-2 agonist, clonidine, combined to spontaneous ventilation (SV) + pressure support ventilation (PS).

METHODS

Sedation was provided by an alpha-2 agonist, clonidine 1-2 microg x kg(-1( x h(-1), without bolus administration, and supplemented with a neuroleptic, loxapine, if needed. Four patients presenting with ARDS were managed with pressure support ventilation (PS = 8 cm H20,rarely 10-12 cm H20) and high PEEP (10-20 cm H20). Energy requirements were minimized, if appropriate, with hypothermia caused by extra-renal replacement therapy or intentional hypothermia (35-36 degrees C). Repeated echocardiographic examinations revealed no right ventricular failure.

RESULTS

Recovery of ARDS, i.e. sustained increase of P/F > 200 for > 24 h, was observed, over 2-5 days.

CONCLUSION

Use of an alpha-2 agonist as first-line sedative agent led to absence of respiratory depression and spontaneous ventilation. Upon ARDS, the lowered intrathoracic pressure observed with SV+PSV allowed one to recruit alveoli with high levels of PEEP, without impairing right ventricle function.

Prevention of nosocomial pneumonia in intubated patients: respective role of mechanical subglottic secretions drainage and stress ulcer prophylaxis

Chronic microaspiration through a tracheal cuff is the main culprit in the penetration and colonization of the lower respiratory tract. A total of 145 patients intubated for more than 3 days were randomly assigned to a double nosocomial pneumonia (NP) prevention: 1--Prevention of aspiration by hourly subglottic secretion drainage (SSD) with a specific endotracheal tube (HI-LO Evac tube, Mallinckrodt); 2--Prevention of gastric colonization using either sucralfate or antacids. Four random groups were defined, similar in age and severity of illness. Subglottic secretion drainage treatment was associated with: a) a twice lower incidence of NP (no-SSD: 29.1%, SSD: 13%); b) a prolonged time of onset of NP (no-SSD: 8.3 +/- 5 days, SSD: 16.2 +/- 11 days); c) a decrease in the colonization rate from admission to end-point day in tracheal aspirates (no-SSD: +21.3%, SSD: +6.6%) and in subglottic secretions (no-SSD: +33.4%, SSD: +2.1%). Sucralfate was not associated with a significantly lower incidence of NP (antacids: 23.6%, sucralfate: 17.8%), but with a lower increase in the colonization rate in subglottic and gastric aspirates, from admission to end-point day.