Background

Weaning may represent 40% of the time spent by patients on mechanical ventilation (MV). A stable cardiovascular system and minimum dose of vasopressor medication is required to withdraw from MV in current guidelines. We found no evidence to support this practice, and this can lead to an unnecessary prolonged time of MV.

Objective

To evaluate whether the use of norepinephrine (NE) interferes with weaning success (WS) in septic patients.

Design

A prospective observational clinical study.

Methods

All patients were on MV for more then 48 hours. Patients able to be weaned according to the institutional protocol were submitted to a spontaneous breathing trial (SBT) during 30 min and followed for 48 hours after extubation. All patients had blood gas analyses, hemodynamic (heart rate [HR], mean arterial pressure [MAP]) and ventilatory parameters (respiratory rate, tidal volume, f/Vt, maximal inspiratory pressure [MIP]) recorded. The outcome was a return to MV within 48 hours after extubation. Data are expressed as mean ± SD and were compared by two-way t test and chi-squared; P < 0.05 was considered significant.

Results

Sixty-three septic shock patients were included from January to September 2004. Mean age was 59.6 ± 17.6 years and APACHE II score was 20.3 ± 6.5. The reintubation rate was 19% and mortality was 15.9% overall. Clinical, hemodynamic and ventilatory variables were not related to weaning outcome.

During acute illness, the maximal NE dose was 0.52 ± 0.29 and 0.12 ± 0.10 μg/kg/min at SBT. Neither the maximal NE dose during septic shock nor the NE dose during SBT were different between weaning failure (WF) and weaning success (WS) patients (Table 1).

Table 1 (abstract P46)
Full size table

Conclusion

NE use was not a contraindication to weaning and extubation from MV in patients recovering from septic shock.