Background Previous research suggests that limitations of life-sustaining treatment (LST) may be more common in women than men, but few studies have included data on clinical reasoning or limitation type. This study aimed to investigate sex differences in LST-limitations in the ICU and in their documented characteristics. Methods All adult (≥18 years) ICU patients registered in the Swedish Intensive Care Register between 2019 and 2024 were included. A multivariable logistic regression model, adjusted for SAPS3 and age, analysed the association between sex and LST-limitations. Limitation characteristics were compared using Chi-square test (categorical variables) and Wilcoxon rank-sum test (numeric variables). Results The cohort included 111,354 patients; 41.7% women. LST-limitations occurred in 24.4% of patients and were more frequent in women than in men (25.3% vs. 23.8%, p < 0.0001). In adjusted analyses women had higher odds of receiving an LST-limitation than men, both in the full cohort (OR 1.21, 95% CI 1.17−1.25) and among 30-day non-survivors (OR 1.24, 95% CI 1.18−1.32). Women received LST-limitations earlier than men (2.8 h after admission vs 4.5 h, p < 0.0001). Acute disease and therapy failure were more often documented reasons in men than in women (78.8% vs 74.3%, p < 0.0001; 21.2% vs. 18.6%, p = 0.0001), whereas autonomy and chronic disease were more frequent in women (7.8% vs 5.9%, p < 0.0001; 63.2% vs. 60.7%, p = 0.0021). Women were more often involved in decision-making (13.3% vs 11.8%, p = 0.0074). Conclusions Women were more likely to receive LST-limitations and received them earlier. Men who died within 30 days were less likely to have had an LST-limitation than women. Documented reasons for LST-limitations differed by sex, and women had higher rates of documented patient involvement.
Background 0.9% saline solution has a supraphysiological chloride concentration and has been associated observationally with acute kidney injury and mortality. How randomized fluid type changes serum chloride early in critical illness, and what determines this change, remain uncertain. Focusing on the first three days after randomization, we estimated the randomized saline-versus-Plasma-Lyte difference in serum chloride and its variation by renal function, the observational association with study-saline volume, and the sources of variation in serum chloride. Methods This secondary analysis of BaSICS (75 Brazilian ICUs; Plasma-Lyte 148 vs 0.9% saline) included participants with baseline serum chloride and at least one measurement on days 1–3. A Bayesian hierarchical longitudinal model estimated the treatment effect over time and its variation by baseline estimated glomerular filtration rate (eGFR). Group-level analyses used day 2, which balanced accumulated exposure against attrition of measurements. We normalized randomized between-group differences, estimated an inverse-probability-weighted within-saline volume association, and partitioned modeled variation in serum chloride. Results Among 3,482 patients (33% of the trial population), serum chloride rose 2.15 mmol/L (95% confidence interval, 1.76–2.53) more with saline than with Plasma-Lyte by day 2, when saline recipients had received on average 145.7 mmol more study-fluid chloride, corresponding to 1.47 mmol/L per 100 mmol of additional chloride (1.17–1.81). Within saline recipients, the weighted association was +0.31 mmol/L per 100 mmol (0.22 to 0.44). The day-2 between-group difference decreased by 0.29 mmol/L (95% credible interval, 0.12 to 0.46) per 15 mL/min/1.73 m2 higher baseline eGFR (+3.0 mmol/L at 30 vs +1.8 mmol/L at 90 mL/min/1.73 m2). Of modeled variation in serum chloride, the fluid component accounted for 0.7% (0.4–1.0; 1.8% with randomized arm included); measured baseline characteristics, almost entirely baseline serum chloride, for 48.1%; persistent patient-specific differences not explained by measured characteristics for 24.5%; and day-to-day within-patient fluctuation for 26.9%. Conclusions Over the first three ICU days, randomization to saline increased serum chloride relative to Plasma-Lyte, and the between-group difference was larger at lower baseline eGFR. Most modeled variation in serum chloride reflected each patient's baseline chloride and persistent patient-specific differences that measured characteristics did not explain; the fluid component was small. Trial registration ClinicalTrials.gov, NCT02875873.
