The Usefulness of Noninvasive Positive Pressure Ventilation in Patients With Acute Respiratory Failure after Extubation

Na, Joo Ock; Lim, Chae Man; Shim, Tae Sun; Park, Joo Hun; Lee, Ki Man; Lee, Sang Do; Kim, Woo Sung; Kim, Dong Soon; Kim, Won Dong; Koh, Younsuck

Abstract

BACKGROUND: Acute Respiratory failure which is developed after extubation in the weaning process from mechanical ventilation is an important cause of weaning failure. Once it was developed, endotracheal reintubation has been done for respiratory support. Noninvasive Positive Pressure Ventilation (NIPPV) has been used in the management of acute or chronic respiratory failure, as an alternative to endotracheal intubation, using via nasal or facial mask. In this study, we evaluated the usefulness of NIPPV as an alternative method of reintubation in paients who developed acute respiratory failure after extubation. METHOD: We retrospectively analyzed thirty one patients (eighteen males and thirteen females, mean ages 63+/-13.2 years) who were developed acute respiratory failure within forty eight hours after extubation, or were extubated unintentionally at medical intensive care unit(MICU) of Asan Medical Center. NIPPV was applied to the patients. Ventilatory mode of NIPPV, level of ventilatory support and inspiratory oxygen concentration were adjusted according to the patient condition and results of blood gas analysis by the attending doctors at MICU. NIPPV was completely weaned when the patients maintained stable clinical condition under 8 cmH2O of pressure support level. Weaning success was defined as maintenance of stable spontaneous breathing more than forty eight hours after discontinuation of NIPPV. Respiratory rate, heart rate, arterial blood gas analysis, level of pressure support, and level of PEEP were monitored just before extubation, at thirty minutes, six hours, twenty four hours after initiation of NIPPV. They were also measured at just before weaning from NIPPV in success group, and just before reintubation in failure group.
RESULTS
1) NIPPV was successfully applied to thirty-one patients of thirty-two trials and one patient could not tolerated NIPPV longer than thirty minutes. Endotracheal reintubation was successfully obviated in fourteen patients (45%) among them. 2) There was no difference in age, sex, APACHE III score on admission at MICU, duration of intubation, interval from extubation to initiation of NIPPV, baseline heart rate, respiratory rate, arterial blood gas, and PaO2/FiO2 between the success and the failure group. 3) Heart rate and respiration rate were significantly decreased with increase SaO2 after thirty minutes of NIPPV in both groups (p<0.05). Ho wever, in the patients of failure group, heart rate and respiratory rate were increased again with decrease in SaO2 leading to endotracheal reintubation. 4) The success rate of NIPPV treatment was significantly higher in the patients with COPD compared to other diseases (62% vs 39%) (p=0.007). 6) The causes of failure were deterioration of arterial blood gas without aggravation of underlying disease (n=9), aggravation of undelying disease (n=5), mask intolerance (n=2), and retained airway secretion (n=1).
CONCLUSION
NIPPV would be a useful therapeutic alternative which can avoid reintubation in patient who developed acute respiratory failure after extubation.