Reduction of heart rate variability after colorectal resections

BACKGROUND: Heart rate variability (HRV) is a sensitive marker of altered sympathetic-parasympathetic function and is reduced in inflammation, illness, and trauma. The effect of major abdominal surgery on the course of HRV parameters is still an issue requiring further investigation.

MATERIALS AND METHODS: A prospective, observational study including 40 consecutive patients undergoing elective colorectal surgery under "fast-track" perioperative management. Time and frequency domain parameters of HRV were measured 1 day prior to operation and on days 1-5 postoperatively. General and surgical complications as well as the course of leucocytes and C-reactive protein (CRP) were documented and correlated to the HRV measurements.

RESULTS: Time domain parameters of HRV showed a significant decrease compared to the preoperative values on postoperative day 1 and returned to baseline on day 2, demonstrating impaired autonomic regulation in the early postoperative period. No correlation to complications or course of leukocytes or CRP was significant in our study.

CONCLUSIONS: Colorectal resections significantly influence the HRV course. The autonomic regulation is reduced in the early postoperative time and all parameters return to baseline until the third day.