Differences between women and men in prolonged weaning

Background: In recent years, the importance of sex as a factor influencing medical care has received increasing attention in the field of intensive care medicine. The objective of this study was to examine the influence of sex in prolonged weaning. Methods: A retrospective analysis of patients undergoing prolonged weaning at Thoraxklinik, University Hospital Heidelberg between 12/08 and 12/23 was conducted. Patients with neuromuscular diseases were excluded from the analyses. The risk factors for weaning failure in men and women were identified through stepwise cox-regression analyses. Results: A total of 785 patients were included, of whom 313 (39.9%) were women. 77.9% of the women and 75.4% of the men were successfully weaned from invasive ventilation. In group comparisons and multivariable analyses, sex was not found to be a risk factor for weaning failure. Cox regression analyses were performed separately for both sexes on the outcome of weaning failure, adjusting for relevant covariates. The results indicated that age ≥ 65 years (HR 2.38, p < 0.001) and the duration of IMV before transfer to the weaning centre (HR 1.01/day, p < 0.001) were independent risk factors in men. In women, however, the duration of IMV before transfer (HR 1.01, p < 0.001), previous non-invasive ventilation (HR 2.9, p 0.005), the presence of critical illness polyneuropathy (HR 1.82; p = 0.040) and delirium (HR 2.50, p = 0.017) were identified as relevant risk factors. In contrast delirium was associated with a favourable weaning outcome in men (HR 0.38, p = 0.020) and nosocomial pneumonia as a reason for prolonged weaning in women (HR 0.43; p = 0.032). Conclusion: The analyses indicate that there are sex-based differences in the risk factors associated with weaning failure. Further studies, ideally prospective, should confirm these findings to assess whether sex is a factor that should be taken into account to improve weaning outcomes.