Intensive care medicine essentials [CICM]: Overview

The “ICU Toolbox” collection provides practical advice on a range of special focus topics. It aims to be a beacon of practical insights, offering concise and insightful hands-on guidance for healthcare professionals navigating the intricate landscapes of intensive care, and providing them with tangible tools and strategies to enhance their daily practice.

Abstract
Background: Septic shock is common and associated with significant morbidity and mortality. The ADRENAL trial examined the use of hydrocortisone in patients with septic shock, demonstrating no difference in patient-centred outcomes but a decrease in the time to shock resolution. The change in clinical practice related to the publication of the ADRENAL trial is currently unknown.

Methods: A retrospective cohort study examining the use of hydrocortisone in patients with septic shock was conducted in 12 intensive care units (ICUs). A segmented linear regression was performed to identify a stepwise change in hydrocortisone administration and 90-day mortality associated with the publication of the ADRENAL trial.

Results: We included 4,198 patients with a mean age of 58 years (standard deviation, SD17), and the median noradrenaline equivalent score (NEE) was 0.07 µg/kg/min (IQR 0.02 - 0.17). Segmented regression analysis for hydrocortisone administration identified two breakpoints, 3 months before and 6 months after publication, leading to three periods: Pre-publication, Transition and Post-publication. Compared to the pre-publication period, the Transition and Post-publication cohorts had a higher proportion of hydrocortisone administration (28% vs. 34% vs. 43%; p < 0.0001). Furthermore, after adjustment for temporal change, the transition period had a significant change in the slope of the proportion of patients receiving hydrocortisone (-0.1% per month vs. +1.4% per month; p = 0.026), whereas this was not statistically significant during the post-publication period (+0.1% per month, p = 0.66). After adjusting for confounders, the Transition and Post-publication periods were independently associated with an increase in hydrocortisone (OR 1.4, 95% CI 1.14 - 1.77; p = 0.0015 and OR 2.03; 95% CI 1.74 - 2.36; p < 0.001, respectively). Furthermore, after adjusting for confounders, when compared to the Pre-transition period, the use of hydrocortisone was associated with a statistically significant decrease in 90-day mortality (14% vs. 24% absolute difference, aHR for hydrocortisone effect -0.81; 95% CI 0.65 - 0.99; p = 0.044).

Conclusion: Publication of the ADRENAL trial changed clinical practice in Queensland ICUs with increased prescription of hydrocortisone for patients with septic shock with an associated reduction in mortality.

Keywords: septic shock hydrocortisone ADRENAL trial critical care.

Abstract
Background: Ketamine and fentanyl are commonly used for sedation and induction of anesthesia in critically ill patients. This study aimed to compare the hemodynamic effects of ketamine versus fentanyl bolus in patients with septic shock.

Methods: This randomized controlled trial included mechanically ventilated adults with septic shock receiving sedation. Patients were randomized to receive either 1 mg/kg ketamine bolus or 1 mcg/kg fentanyl bolus. Cardiac output (CO), stroke volume (SV), heart rate (HR), and mean arterial pressure (MAP) were measured at the baseline, 3, 6, 10, and 15 min after the intervention. Delta CO was calculated as the change in CO at each time point in relation to baseline measurement. The primary outcome was delta CO 6 min after administration of the study drug. Other outcomes included CO, SV, HR, and MAP.

Results: Eighty-six patients were analyzed. The median (quartiles) delta CO 6 min after drug injection was 71(37, 116)% in the ketamine group versus - 31(- 43, - 12)% in the fentanyl group, P value < 0.001. The CO, SV, HR, and MAP increased in the ketamine group and decreased in the fentanyl group in relation to the baseline reading; and all were higher in the ketamine group than the fentanyl group.

Conclusion: In patients with septic shock, ketamine bolus was associated with higher CO and SV compared to fentanyl bolus.

Abstract
Study objective: Compare physician gestalt to existing screening tools for identifying sepsis in the initial minutes of presentation when time-sensitive treatments must be initiated.

Methods: This prospective observational study conducted with consecutive encounter sampling took place in the emergency department (ED) of an academic, urban, safety net hospital between September 2020 and May 2022. The study population included ED patients who were critically ill, excluding traumas, transfers, and self-evident diagnoses. Emergency physician gestalt was measured using a visual analog scale (VAS) from 0 to 100 at 15 and 60 minutes after patient arrival. The primary outcome was an explicit sepsis hospital discharge diagnosis. Clinical data were recorded for up to 3 hours to compare Systemic Inflammatory Response Syndrome (SIRS), Sequential Organ Failure Assessment (SOFA), quick SOFA (qSOFA), Modified Early Warning Score (MEWS), and a logistic regression machine learning model using Least Absolute Shrinkage and Selection Operator (LASSO) for variable selection. The screening tools were compared using receiver operating characteristic analysis and area under the curve calculation (AUC).

Results: A total of 2,484 patient-physician encounters involving 59 attending physicians were analyzed. Two hundred seventy-five patients (11%) received an explicit sepsis discharge diagnosis. When limited to available data at 15 minutes, initial VAS (AUC 0.90; 95% confidence interval [CI] 0.88, 0.92) outperformed all tools including LASSO (0.84; 95% CI 0.82 to 0.87), qSOFA (0.67; 95% CI 0.64 to 0.71), SIRS (0.67; 95% 0.64 to 0.70), SOFA (0.67; 95% CI 0.63 to 0.70), and MEWS (0.66; 95% CI 0.64 to 0.69). Expanding to data available at 60 minutes did not meaningfully change results.

Conclusion: Among adults presenting to an ED with an undifferentiated critical illness, physician gestalt in the first 15 minutes of the encounter outperformed other screening methods in identifying sepsis.