Reverse Triggering Dyssynchrony 24 h after Initiation of Mechanical Ventilation

Abstract

Background Reverse triggering is a delayed asynchronous contraction of the diaphragm triggered by passive insufflation by the ventilator in sedated mechanically ventilated patients. The incidence of reverse triggering is unknown. This study aimed at determining the incidence of reverse triggering in critically ill patients under controlled ventilation. Methods In this ancillary study, patients were continuously monitored with a catheter measuring the electrical activity of the diaphragm. A method for automatic detection of reverse triggering using electrical activity of the diaphragm was developed in a derivation sample and validated in a subsequent sample. The authors assessed the predictive value of the software. In 39 recently intubated patients under assist-control ventilation, a 1-h recording obtained 24 h after intubation was used to determine the primary outcome of the study. The authors also compared patients’ demographics, sedation depth, ventilation settings, and time to transition to assisted ventilation or extubation according to the median rate of reverse triggering. Results The positive and negative predictive value of the software for detecting reverse triggering were 0.74 (95% CI, 0.67 to 0.81) and 0.97 (95% CI, 0.96 to 0.98). Using a threshold of 1 μV of electrical activity to define diaphragm activation, median reverse triggering rate was 8% (range, 0.1 to 75), with 44% (17 of 39) of patients having greater than or equal to 10% of breaths with reverse triggering. Using a threshold of 3 μV, 26% (10 of 39) of patients had greater than or equal to 10% reverse triggering. Patients with more reverse triggering were more likely to progress to an assisted mode or extubation within the following 24 h (12 of 39 [68%]) vs. 7 of 20 [35%]; P = 0.039). Conclusions Reverse triggering detection based on electrical activity of the diaphragm suggests that this asynchrony is highly prevalent at 24 h after intubation under assist-control ventilation. Reverse triggering seems to occur during the transition phase between deep sedation and the onset of patient triggering. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

The physiological underpinnings of life-saving respiratory support

“…Second, even when all mechanical breaths are initiated by time (i.e., controlled), a patient's breathing effort might still occur in the form of reverse triggering efforts in which patient's breathing efforts are "entrained" by the passive insufflations [25], a phenomenon which is very frequent in the transition from fully controlled to assisted mechanical ventilation [26] (see Fig. 4).…”

Reverse Trigger in Ventilated Non-ARDS Patients: A Phenomenon Can Not Be Ignored!

“…We supposed that the proportional relationship between diaphragm contraction force and ventilator energy played the key role in the occurrence of RT, which was in line with the mechanisms of the entrainment. Recently Mellado Artigas et al (2021) found that the incidence of RT was higher in patients who had more patient-triggered breaths or were more likely to be extubated. Their retrospective results also support our assumption.…”

Reverse Triggering: An Introduction to Diagnosis, Management, and Pharmacologic Implications

“…However, recent literature has been unable to show a significant correlation between sedative dosing and incidence of reverse triggering ( Rodriguez et al, 2020a ). Other reports suggest that the occurrence of reverse triggering may represent the transition between deep sedation and recovery of the patient’s respiratory drive ( Mellado Artigas et al, 2021 ).…”