Postoperative lumbar microdiscectomy pain. Minimalization by irrigation and cooling.

ABSTRACT

STUDY DESIGN: Seventy patients undergoing de novo lumbar microdiscectomy were prospectively randomized into a control group and a group in which cold intraoperative wound irrigation along with postoperative wound cooling was used. Postoperative analgesia requirements and length of hospital stay were analyzed and correlated. OBJECTIVES: To evaluate the role of intraoperative cold irrigation and postsurgical cooling in minimizing postoperative lumbar discectomy pain. SUMMARY OF BACKGROUND DATA Regulated hypothermia has been used frequently in pain reduction; however, the efficacy of such a strategy in lumbar disc procedures has not been established. METHODS: Seventy patients (43 men and 27 women), operated on the first time for lumbar disk herniation were prospectively randomized into two groups. A standard microdiscectomy was performed on all patients. In cohort A the wound site was irrigated with a cold (18 C) 5% bacitracin solution for 5 minutes. Additionally, a cooling microtemperature pump was placed on the wound site for 24 hours after surgery. The patients in the control group (cohort B) were treated in a standard fashion without additional hypothermic therapy. All patients received postoperative analgesia through a self-administered morphine pump. The amount of postoperative analgesia received was calculated in morphine equivalents per kilogram. The length of hospital stay was also noted. RESULTS: The total amount of pain medication was significantly smaller in cohort A than in the control group (cohort B). For the statistical analysis of the results, covariate analyses for both the length of hospital stay and the morphine dose were used, demonstrating a statistically significant difference with P = 0.0001. No postoperative wound infection was noted in either group. CONCLUSIONS: Intraoperative and postoperative wound site cooling is a safe, inexpensive, and efficient therapeutic method. It reduces the patients' postoperative pain, promotes earlier ambulation and decreases the length of hospital stay.