Mean arterial pressure versus cardiac index for haemodynamic management and myocardial injury after hepatopancreatic surgery: A randomised controlled trial.

BACKGROUND

Myocardial injury after noncardiac surgery (MINS) frequently complicates the peri-operative period and is associated with increased mortality.

OBJECTIVES

We hypothesised that cardiac index (CI) based haemodynamic management reduces peri-operative high-sensitive troponin-T (hsTnT) elevation and MINS incidence in patients undergoing hepatic/pancreatic surgery compared to mean arterial pressure.

DESIGN

A randomised controlled study.

SETTING

A single-centre study conducted in a university-affiliated tertiary hospital between June 2022 and March 2023.

PATIENTS: Ninety-one patients, who were ≥ 65 years old or ≥ 45 years old with a history of at least one cardiac risk factor were randomised to either mean arterial pressure (MAP) based ( n  = 45) or CI-based ( n  = 46) management groups, and completed the study.

INTERVENTIONS: In group-MAP, patients received fluid boluses and/or a noradrenaline infusion to maintain MAP above the predefined threshold. In group-CI, patients received fluid boluses and/or dobutamine infusion to keep CI above the predefined threshold. When a low MAP was observed despite a normal CI, a noradrenaline infusion was started.

MAIN OUTCOME MEASURES: The primary outcome was peri-operative hsTnT elevation. The secondary outcomes were MINS incidence and 90-day mortality.

RESULTS

The median absolute troponin elevation was 4.3 ng l -1 (95% CI 3.4 to 6) for the CI-based group, and 9.4 ng l -1 (95% CI 7.7 to 12.7) for the MAP-based group (median difference: 5.1 ng l -1 , 95% CI 3 to 7; P  < 0.001). MINS occurred in 8 (17.4%) patients in the CI-based group and 17 (37.8%) patients in the MAP-based group (relative risk: 0.46, 95% CI: 0.22 to 0.96; P  = 0.029). Two patients in group-MAP died from cardiovascular-related causes. One patient in group-CI and two in group-MAP died from sepsis-related complications (for all-cause mortality: χ2  = 1.98, P  = 0.16). MAP-AUC and CI-AUC values of the CI- and MAP-based groups were 147 vs. 179 min × mmHg ( P  = 0.85) and 8.4 vs. 43.2 l m -2 min -1  × min ( P  < 0.001), respectively.

CONCLUSIONS

CI-based haemodynamic management assures sufficient flow and consequently is associated with less peri-operative hsTnT elevation and lower incidence of MINS compared to MAP.

TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05391087.