Invasive blood pressure monitoring does not improve survival in septic critically ill patients

Invasive blood pressure (BP) monitoring with arterial catheters is commonly used in the management of septic shock, however its impact on recovery remains unclear. We aimed to determine whether invasive BP monitoring improves survival, impacts length of stay (LOS) or accelerates shock resolution.

We conducted a multicenter case-control study of ICU patients with septic shock from January 2021 to December 2023. Cases received arterial lines for invasive BP monitoring; controls did not. Patients were matched 1: 1 based on exact Sequential Organ Failure Assessment (SOFA) score, mechanical ventilation status, and propensity scores using age, race, and sex. Primary outcomes were all-cause inpatient mortality and ICU LOS.

Among 739 eligible patients, 326 were matched. The mean age was 67 ± 14 years, and 57 % were male. Inpatient mortality was similar between cases and controls (41 % vs. 38 %, p = 0.43). Patients with arterial lines had longer ICU LOS (median 5.6 vs. 3.7 days, p < 0.01). Time to vasopressor discontinuation (28.6 vs. 26.5 h, p = 0.82) did not differ significantly. Patients with arterial lines had more daily blood draws (median 9 vs. 7, p = 0.046), lower nadir hemoglobin levels (median 7.0 vs. 7.8 g/dL, p < 0.01), and received more red blood cell transfusions (median 2.2 vs. 1.5 units, p = 0.03).

Invasive BP monitoring with arterial catheters did not improve survival in critically ill patients with septic shock. It was associated with longer lengths of stay, increased blood sampling, and higher transfusion requirements. These findings suggest the need to reassess the routine use of arterial lines in this population.