Oxygen therapy with nasal cannula reduces the risk of reintubation in the ICU

Dr. Cesar Laborda, member of the Shock, Organ Dysfunction and Resuscitation group of Vall d'Hebron Research Institute (VHIR), has participated in a multicentre study that concludes that oxygen therapy with high-flow nasal cannula reduces risk of reintubation, compared with conventional therapy, among mechanically ventilated patients at low risk of reintubation.

The high-flow system with nasal cannula is designed to deliver a mixture of air and humidified and heated oxygen higher than the patient's respiratory flow stream. The high flow has several advantages over conventional low-flow oxygen therapy in terms of humidification, oxygenation, gas exchange and breathing pattern. Compared with low-flow oxygen or high-concentration oxygen mask, high-flow nasal cannula with improves patient tolerance to reduce the sensation of breathlessness and dry mouth.

The randomized multicentre clinical trial was carried out in 7 intensive care units (ICUs) of Spain from September 2012 to October 2014. The patients were 527 adults in critical state who had received mechanical ventilation for more than 12h. All of them were recruited for the study when they were ready for the scheduled extubation.

Patients were randomly assigned to undergo conventional oxygen therapy or oxygen therapy with high-flow nasal cannula during 24 hours after extubation. The application of high-flow therapy was restricted to 24 hours because this is the standard monitoring time before patients are discharged to the ICU, which is the environment in which the study was conducted. Over 72 hours after extubation several variables were recorded, and patients were monitored until they were discharged.

Out of 527 patients, 264 received high-flow therapy and 263 received conventional oxygen therapy, and clinical and demographic characteristics of the patients in both groups were similar. Reintubation during the next 72 hours was less frequent in the group of high-flow (13 patients, 4.9%) to 32 patients (12.2%) in the conventional group.

According to Dr. Laborda, the study showed that "high-flow therapy promotes the success of extubation in different ways: improves oxygenation and reduces other causes of respiratory insufficiency" as an increase in the work of breathing and fatigue of the respiratory muscles, often associated with reintubation secondary to hypoxia. Previous studies demonstrated that high-flow oxygen therapy improves the handling of respiratory secretions, and the lowest rate of secondary reintubations in obstruction of the superior airways in the high-flow group in this study corroborates it.