Purpose To determine whether use of a therapist and nurse-driven weaning protocol to wean and extubate patients with trauma from mechanical ventilation (MV) resulted in decreased MV days and intensive care unit (ICU) length of stay (LOS), and to determine time to spontaneous breathing trial (SBT) failure.

Relevance: Many patients with traumatic injuries require MV. Weaning from ventilatory support may be difficult in 25% of patients. There are many risks and complications associated with prolonged MV, which may be minimized by extubating patients from MV as soon as possible. However, premature extubation and subsequent re-intubation may lead to significant increases in infection and mortality. Numerous studies have demonstrated the benefit of allied health worker-driven weaning protocols in decreasing MV days.

Methodology

Participants: 56 MV patients suffering traumatic injuries were enrolled in two phases, and matched for gender, age, type and severity of injury (ISS).
Methods: A weaning protocol was developed using various existing clinical guidelines. A prospective cohort of 28 patients (Phase I), weaned according to protocol, was matched retrospectively with a historical cohort of 28 patients (Phase II), weaned according to physician preference.
Analysis: Logistic regression and Kaplan-Meier survival estimates analysed relationships between age, gender, type and ISS, and total MV time and ICU LOS. Log-rank testing was applied to compare outcomes for MV and ICU LOS. Odds ratio analysis evaluated the relationship between re-intubations in each group. For Phase I patients, time to and reason for SBT failure was recorded.

Results

For MV days the two day difference between groups was not statistically significantly (p = 0.3 ; Phase I = 14.4 days vs Phase II = 16.3 days). The difference of 0.25 days for ICU LOS was not statistically significant (p = 0.9; Phase I = 20.8 days vs Phase II = 21 days). Re-intubation rate was similar for both groups (Phase I = 3/28 vs Phase II = 4/28). Patients in Phase I that failed SBT had higher ISS (16.1 vs 14.5) and longer MV times (20.5 days vs 14.4 days) than the average Phase I patient

Discussion and conclusion

Discussion: Although not statistically significant, the two day reduction in MV was considered clinically significant in view of complications associated with longer ventilation. However, reduced MV days may not result in reduced ICU days.

Phase I patients who failed SBT suffered more severe illness. They failed SBT late in the trial, suggesting fatigue that may require longer SBTs to assess extubation readiness.

Conclusions: The use of physiotherapist and nurse-driven weaning protocols in ventilated patients with traumatic injury led to a clinically significant reduction in MV time, reducing risks of complications, without compromising safety. Longer SBTs must be considered for longer-term patients. Further work should focus on refining protocol criteria, and larger study groups.
Implications: The role of physiotherapists and nurses in weaning from MV could be expanded in South Africa.

Ethical clearance Obtained from Human research ethics committee (medical), University of the Witwatersrand, Johannesburg, South Africa, Clearance number R14/49 Plani.