Study objective: To determine whether the use of continuous IV sedation is associated with prolongation of the duration of mechanical ventilation.
Design: Prospective observational cohort study.
Setting: The medical ICU of Barnes-Jewish Hospital, a university-affiliated urban teaching hospital.
Patients: Two hundred forty-two consecutive ICU patients requiring mechanical ventilation.
Interventions: Patient surveillance and data collection.
Measurements and results: The primary outcome measure was the duration of mechanical ventilation. Secondary outcome measures included ICU and hospital lengths of stay, hospital mortality, and acquired organ system derangements. A total of 93 (38.4%) mechanically ventilated patients received continuous IV sedation while 149 (61.6%) patients received either bolus administration of IV sedation (n=64) or no IV sedation (n=85) following intubation. The duration of mechanical ventilation was significantly longer for patients receiving continuous IV sedation compared with patients not receiving continuous IV sedation (185±190 h vs 55.6±75.6 h; p<0.001). Similarly, the lengths of intensive care (13.5±33.7 days vs 4.8±4.1 days; p<0.001) and hospitalization (21.0±25.1 days vs 12.8±14.1 days; p<0.001) were statistically longer among patients receiving continuous IV sedation. Multiple linear regression analysis, adjusting for age, gender, severity of illness, mortality, indication for mechanical ventilation, use of chemical paralysis, presence of a tracheostomy, and the number of acquired organ system derangements, found the adjusted duration of mechanical ventilation to be significantly longer for patients receiving continuous IV sedation compared with patients who did not receive continuous IV sedation (148 h [95% confidence interval: 121, 175 h] vs 78.7 h [95% confidence interval: 68.9, 88.6 h]; p<0.001).
Conclusion: We conclude from these preliminary observational data that the use of continuous IV sedation may be associated with the prolongation of mechanical ventilation. This study suggests that strategies targeted at reducing the use of continuous IV sedation could shorten the duration of mechanical ventilation for some patients. Prospective randomized clinical trials, using well-designed sedation guidelines and protocols, are required to determine whether patient-specific outcomes (eg, duration of mechanical ventilation, patient comfort) can be improved compared with conventional sedation practices.