Hemodynamic effects of laparoscopic radiofrequency ablation of liver tumors versus laparoscopic hepatic ultrasound examination

Study Objective: To compare the hemodynamic changes that occur during laparoscopic radiofrequency ablation of liver metastases with those occurring during laparoscopic ultrasound hepatic examination alone. Design: Prospective, observational study. Setting: Operating rooms of a university-affiliated hospital. Patients: 40 ASA physical status 2 and 3 patients with liver metastases. Interventions: 20 patients underwent laparoscopic radiofrequency ablation of liver tumors following laparoscopic ultrasound examination, and 20 had laparoscopic ultrasound examination alone. The anesthetic technique was standardized. Measurements: The primary endpoint of the study was the number of episodes of mean arterial pressure (MAP) < 70 mmHg. Secondary endpoints were significant differences between the groups in MAP, heart rate, cardiac index, ejection fraction (EF; both measured with thoracic bioimpedance), calculated systemic vascular resistance index (SVRI), and central venous pressure. Main Results: The number of episodes of MAP < 70 mmHg did not differ between groups: there were 9 episodes in the ultrasound alone group and 7 in the radiofrequency group (P = 0.668). Cardiac index, EF, and SVRI were similar between groups. Central venous pressure was slightly higher in the radiofrequency group [11.99 (10.8-13.2) mmHg vs. 10.3 (9.2-11.4) mmHg, P = 0.04]. Conclusions: Hemodynamic profiles were similar when comparing laparoscopic radiofrequency ablation of liver metastases with laparoscopic ultrasound hepatic examination alone.