Background
Epidural opiate analgesia carried by gelfoam in the epidural space is to improve the quality of perioperative pain relief. The aim of this study was to compare the analgesic efficacy of gelfoam soaked in morphine with crystalloids versus colloid versus direct application of morphine in epidural space in patients undergoing lumbar laminectomy under general anesthesia.
Methods
This study was a prospective, randomized, double-blinded trial. 75 male and female patients aged from 18 to 65 years  from ASA class I or II scheduled for Lumbar laminectomy surgery were randomly divided into three equal groups: group A: (control group): 5 ml of 1 mg/ml morphine was directly instilled over intact epidural space, group B (crystalloid group): apiece of gelfoam 5 cm × 1 cm soaked in 5 mg morphine diluted with 5 ml crystalloid (0.9% sodium chloride) placed in intact epidural space; and group C (colloid group): apiece of gelfoam 5 cm × 1 cm soaked in 5 mg morphine diluted with 5 ml hydroxyethyl starch 6% (HES 6%) placed in intact epidural space by the neurosurgeon. Total analgesics, time to first analgesic request, visual analogue scale (VAS), hemodynamics, respiratory rates and adverse effects were recorded.
Results
As regards Patient’s characteristics, age, gender, weight, ASA class and operative time were comparable in all studied groups, and groupsB and C showed less amount of analgesia, long time to analgesic request, and less main VAS. No statistically significant differences are in hemodynamics, and the incidences of side effects showed no statistically significant differences among the three groups of study.
Conclusion
Epidural use of gelfoam soaked by morphine in HES 6% is an effective method for post operative analgesia after lumbar laminectomy.