Long-term use of neuromuscular blockers associated with increased 90-day mortality in mechanically ventilated patients in the ICU: a retrospective cohort study

Objective To analyze the safety and efficacy of neuromuscular blockers (NMBAs) in mechanically ventilated patients in the ICU. Methods A retrospective analysis was conducted on data from adult patients admitted to the ICU of Deyang People's Hospital and received mechanical ventilation from 2015 to 2022. Demographic characteristics, laboratory data, mechanical ventilation parameters ［positive end-expiratory pressure (PEEP), mean airway pressure (Pmean), peak airway pressure (Ppeak)］, arterial blood gas data ［pH, arterial oxygen partial pressure (PaO2), arterial carbon dioxide partial pressure (PaCO2)］, NMBA usage, length of ICU stay, and 90-day mortality were collected and analyzed. Results A total of 2 765 mechanically ventilated patients were included, of which 55.23% were male, aged (69.89±14.66) years, and the 90-day mortality rate during ICU stay was 30.78% (851/2765). Compared to the survivors, the mortality group had an older age, lower BMI, as well as higher sequential organ failure assessment (SOFA) score, acute physiological score (APS), systemic inflammatory response syndrome (SIRS) score, simplified acute physiology score Ⅱ (SAPS Ⅱ) score and Oxford acute severity of illness score (OASIS) (P＜0.05). In the mortality group, the duration of mechanical ventilation was longer ［137 (90, 237)h vs 75 (36, 143)h, Z=15.22, P<0.05］, and the length of ICU stay was longer ［7 (5, 12)d vs 5 (3, 10)d, Z=11.39, P<0.05］, and were also more likely to receive NMBA treatment for more than 48 hours (4.23% vs 1.67%, P＜0.05) compared to the survival group. After adjusting for age, sex, and relevant covariates, the use of NMBAs for more than 48 hours was found to be independently associated with increased mortality risk (adjusted HR=2.48, 95%CI: 1.75-3.50). Subgroup analysis showed that this association was stronger in patients requiring higher PEEP (HR=2.90, 95%CI: 1.72-4.88). Conclusion Long-term use of NMBA is associated with an increased long-term mortality risk in critically ill patients requiring mechanical ventilation. Further research is needed to validate these findings.