Audit of compliance with ventilation protocol in severe head injuries: a retrospective study

Introduction

A reduction in mortality of severe head injury patients is associated with the development of evidence-based protocols [1, 2]. This audit studies the adherence to the neurointensive care unit (NICU) protocol for the management of respiratory parameters in severely head injured patients in the first 24 hours.

Methods

A random case note review was undertaken of 50 patients intubated prior to admission to NICU, between March 2005 and April 2007. All data in the first 24 hours was compared with protocol targets.

Results

There were 170 severely head injured patients admitted to the NICU in the defined period. Patients reviewed were 39 males, 11 females; median age 34 years, range 17–74 years. The median presenting GCS was 7. Eighteen patients had thoracic pathology on admission, these included seven spinal fractures, four haemothoraces, one sternal fracture, six rib fractures, six aspiration pneumonitis and one collapsed lung. Admission ventilation targets and their compliance were measured. The results were ventilation mode (SIMV) 98% compliance, tidal volume (6–10 ml/kg) 96%, FIO₂ (30–40%) 38%, respiratory rate (12–16) 30%, I:E ratio (1:2) 78% and PEEP (5–10 cmH₂O) 94%. See Table 1.

Table 1 Blood gas analysis

Conclusion

Overall our audit detected only 18 protocol deviations out of 311 interventions regarding maintenance of adequate oxygenation and tight PaCO₂ control (6%). There were 78 episodes out of 397 samples taken where the protocol should have been activated for the management of PaCO₂ control (20%).

Protocols can reduce mortality but knowledge of adherence to protocols is necessary to improve clinical practice.