Spontaneous Breathing Trials Don't Aid Decision Making in Extreme Preemies

By Reuters Staff

December 24, 2019

NEW YORK (Reuters Health) - Spontaneous breathing trials (SBTs) are increasingly being used to help determine readiness for extubation in mechanically ventilated extremely preterm neonates, but a new study suggests they provide little added value over clinical judgement alone and may be risky.

As currently performed, SBTs are "unwarranted in clinical practice because they may expose neonates to clinical instability without improving the ability to assess extubation readiness," Dr. Guilherme Sant'Anna from Montreal Children's Hospital in Quebec and colleagues conclude.

In a paper in JAMA Pediatrics, they report results of a diagnostic study of 259 neonates (birth weight <1250 g) from five neonatal intensive care units from the prospective Automated Prediction of Extubation Readiness (APEX) study. All of them required mechanical ventilation, were thought to be ready for extubation and underwent endotracheal continuous positive airway pressure (ET-CPAP) before extubation.

The study team recorded cardiorespiratory signals during five minutes of ET-CPAP immediately before extubation and documented signs of clinical instability (apnea requiring stimulation, presence and cumulative durations of bradycardia and desaturation, and increased supplemental oxygen).

More than half of the babies (147 of 259; 57%) developed at least one of these clinical events during ET-CPAP; 10% suffered apneas, 19% bradycardias, 53% desaturations, and 41% had increased need for oxygen.

Compared with babies who failed extubation (defined as reintubation within a week), babies with successful extubation (71%) had significantly fewer clinical events and shorter cumulative bradycardia and desaturation time and less increase in oxygen need.

However, in an algorithm that included multiple clinical event combinations to define SBT success or failure, none had "sufficient accuracy to justify their routine use," the investigators report.

"Arguably," they write, documenting clinical events during ET-CPAP would be justifiable if it could accurately predict which babies would succeed or fail extubation. In their cohort, babies who failed extubation were significantly more likely to have clinical events compared to babies with successful extubation. However, there was "considerable" overlap between these two groups.

"Consequently, when computing the diagnostic performance of all possible SBT definitions, none had an acceptable trade-off between sensitivity and specificity," they note. "In fact, given that nearly one-third of neonates who failed extubation had an uneventful ET-CPAP recording, they would have been automatically misclassified by any SBT definition."

Their findings, they say, are in line with the only study to their knowledge to prospectively audit the consequences of incorporating routine SBTs into clinical practice. That study found that SBT-driven extubation did not improve extubation success rates compared with clinical judgment alone. (http://bit.ly/34VKIC5)

SOURCE: http://bit.ly/391S0as JAMA Pediatrics, online December 20, 2019.