Cutaneous microcirculation during operations with a cardiopulmonary bypass.

Area of Science:

• Cardiovascular Surgery
• Physiology
• Medical Monitoring

Background:

• Cardiac surgery frequently involves cardiopulmonary bypass (CPB) and induced cardiac arrest.
• Cutaneous microcirculation (cMC) is a critical physiological parameter affected by surgical interventions.

Purpose of the Study:

• To investigate the relationship between cMC and hemodynamic parameters in cardiac surgery patients.
• To compare the effects of two distinct cardioplegic solutions on cMC.

Main Methods:

• Twenty patients undergoing cardiac surgery were divided into two groups: Histidine-Tryptophane-α-Ketoglutarate (HTK) solution and blood cardioplegia (BCP).
• Continuous monitoring of cMC using Laser-Doppler-Perfusion (LDP) was performed throughout CPB.
• Hemoglobin concentration (HbC) was measured using a Blood-Parameter-Monitoring-System.

Main Results:

• LDP levels decreased during aortic cross-clamping and were influenced by central venous pressure, mean arterial pressure, and total peripheral resistance.
• Patients receiving BCP exhibited higher relative LDP (RLDP) and relative HbC (RHbC) compared to the HTK group post-cardioplegia administration.
• HTK patients with a body surface area (BSA) < 2 m² showed lower RLDP than those with BSA ≥ 2 m².

Conclusions:

• Cardiopulmonary bypass significantly impacts cMC during cardiac surgery.
• Cutaneous LDP monitoring serves as a valuable non-invasive tool for intraoperative hemodynamic assessment.