Early predictors of success of non-invasive positive pressure ventilation in hypercapnic respiratory failure

Background

Non-invasive positive pressure ventilation (NIPPV) has emerged as a significant advancement in the management of acute hypercapnic respiratory failure.

Method

Patients with hypercapnic respiratory failure requiring ventilation therapy (respiratory rate RR] of > 30 breaths per minutes, PaCO2 > 55 mmHg and arterial pH < 7.35) were included in the study. Baseline clinical parameters and arterial blood gas (ABG) were recorded before initiating NIPPV. Clinical parameters including heart rate (HR), RR, oxygen saturation and ABG were revaluated at 1, 4, and 24 hours after initiation of NIPPV. Change in these parameters and need for intubation was evaluated.

Results

Of the 100 patients, 76 (76%) showed improvement in clinical parameters and ABG. There was improvement in HR and RR, pH, and PCO2 within the first hour in the success group and these parameters continued to improve even after four and 24 hours of NIPPV treatment. Out of 24 (24%) patients who failed to respond, 13 (54%) needed endotracheal intubation within one hour. The failure group had higher baseline HR than the success group.

Conclusion

Improvement in HR, RR, pH, and PCO2 one hour after putting the patient on NIPPV predicts success of non-invasive positive pressure ventilation in hypercapnic respiratory failure.