Deep Parasternal Intercostal Plane Blocks and Their Role in a Cardiac Fast-Track Program.

Objectives: To determine if deep parasternal intercostal plane (DPIP) blocks are associated with reduced opioid consumption and a subsequent reduction in postoperative delirium after cardiac surgery.

Design: A retrospective observational study.

Setting: A single-center tertiary care hospital.

Participants: Three hundred and eight adult patients who underwent cardiac surgery with median sternotomy between March 2021 and February 2023.

Interventions: DPIP blocks are performed after chest closure in the operating room under sterile conditions and with real-time ultrasound guidance. The control group did not receive DPIP blocks.

Measurements And Main Results: Median [range] postoperative hydromorphone consumption at 12 hours was 0.8 [0-2.6] mg vs. 1.2 [0-2.6] mg, p = 0.0004, and at 24 hours was 0.4 [0-3.2] mg versus 0.6 [0-3.4] mg, p = 0.007 in the DPIP and control groups, respectively. Predictors of reduced hydromorphone requirements included the presence of DPIP blocks, use of a dexmedetomidine infusion, and absence of composite comorbidities. Postoperative delirium was present in 17 (11%) and 23 (14.9%) patients in the DPIP block and control groups respectively (odds ratio 0.76; 95% confidence interval 0.38-1.53, p = 0.45). The median [IQR] time to extubation was 135 [65, 274] minutes versus 196.5 [74, 420] minutes in the DPIP and control groups, respectively, p = 0.04. There was no difference with respect to major morbidity and mortality between the two groups.

Conclusions: DPIP blocks were associated with decreased perioperative opioid consumption, and earlier tracheal extubation after cardiac surgery. DPIP blocks may be incorporated within the fast-track cardiac anesthesia pathways; however, alternative strategies need to be further explored to reduce postoperative delirium after cardiac surgery.