Implementation of a weaning algorithm in postoperative cardiac ICU: simple enough to be implemented in a ventilator software

Abstract

Objective The aim of this study was to test the efficacy of a respiratory weaning algorithm (WA) in postoperative cardiac surgery patients. This algorithm was made simple enough to be implemented in medium-end ventilator software. Patients Twenty consecutive postoperative patients who underwent scheduled cardiac surgery with normal postoperative haemodynamic and respiratory status. Methods A 3 step WA (Controlled Mode Ventilation, Pressure Support (PS) at +20 cmH 2O and at +10 cmH 2O) was applied every 15 minute by the same investigator. A 15 minute period of respiratory stability at one step led to commute to a step ahead until patient was judged “ready for extubation” (RFE, i.e. stable during 15 min under PS +10 cmH 2O). Once reaching this time, the patient was left under PS +10 until nurse and doctors in charge decided extubation according to our routine clinical criteria. Results the patients were routinely extubated, in average 187 ± 169 min later than when judged RFE by the algorithm. Heart rate ( P < 0.05) and mean arterial pressure rose when they reached the time of effective extubation, by comparison to the RFE time point. Conclusion A WA has clinical advantage in cardiac surgery as it reduces respiratory weaning duration. It helps to avoiding haemodynamic stress related to delayed extubation. Such an algorithm is simple enough to be implemented in medium-end ventilators.