ICU Physicians' Perception of Patients' Tolerance Levels in Light Sedation Impacts Sedation Practice for Mechanically Ventilated Patients

Purpose: To investigate physicians' perception of patients' tolerance levels regarding sedation, which could affect sedation practice for mechanically ventilated (MV) patients. Methods: This is a questionnaire survey combined with a 24 h cross-sectional study. The physician's propensity score for light sedation (PS-_LS) was estimated by his/her response to the given answers for each item of the questionnaire, which tested the levels of interviewee's desire to manage MV patient with light sedation. Thereby, the mean physicians' PS-_LS of each participating ICU (ICU-_meanPS-_LS) was calculated. The practical measurements of all variables listed on the questionnaire were used to semi-quantitatively assess stimulus intensity of what the recruited patients suffered (i.e., semi-quantitative stimulus intensity, SSI). Sedation depth was assessed by Richmond Agitation Sedation Scale (RASS). Results: 555 of 558 (99.5%) physicians from 102 ICUs were concerned with patients' tolerance levels regarding sedation while titrating sedation depth. The physician's PS-_LS was non-normally distributed with median (IQR) of 3 (0-5). ICU-_meanPS-_LS was calculated in 92 out of 102 ICUs participating in the cross-sectional study, which was ranged from -5 to 7 with a median (IQR) of 2.37 (0.16-4.33). A significant increasing trend in prevalence of light sedation was observed over increasing ICU-_meanPS-_LS quartiles (from Q1 to Q4, χ²-test for trend, p = 0.002). Moreover, odds ratio for probability of light sedation remained significant in MV patients from Q4 ICUs vs. Q1 ICUs, adjusted by APACHE II score (OR, 2.332; 95% CI: 1.463-3.717; p < 0.001) or SSI score (OR, 2.445; 95% CI: 1.468-4.074; p = 0.001). Notably, adjusted OR for mortality was significant in deeply sedated MV patients (OR, 2.034; 95% CI: 1.435-2.884; p < 0.001). Conclusions: ICU physician's individualized perception for patients' tolerance levels regarding sedation, in light sedation affected sedation practice for MV patients.