Local administration of morphine for analgesia after iliac bone graft harvest

BACKGROUND

Harvesting autogenous bone grafts from the ilium may cause considerable pain and may represent a significant source of postoperative morbidity. The local application of morphine can reduce pain in a rat model of bone damage. We evaluated the analgesic efficacy of administering morphine to the donor bone graft site for spinal fusionsurgery.

METHODS

Sixty patients undergoing cervical spinal fusion surgery using autogenous bone harvested from the ilium were randomly assigned to one of three groups: Group 1 was given saline infiltrated into the harvest site, group 2 was given 5 mg intramuscular morphine; group 3 was given 5 mg morphine infiltrated into the harvest site. After surgery, all patients were given morphine through a patient-controlled analgesia pump. Pain scores both from the harvest and the incision sites, as well as morphine use, were recorded at 2, 4, 6, 8, 12, and 24 h after surgery. At 1 yr after surgery the presence and subjective characteristics of donor site pain were recorded.

RESULTS

Total 24-h morphine use (milligrams) was significantly lower (P < 0.0001) in group 3 (33.7+/-8.3 mg, mean +/- SD), compared with either group 1 (64.3+/-6.6 mg) or group 2 (59.6+/-9.3 mg). Pain from the graft site was scored the same at 2 h but remained significantly lower (P < 0.0001) for group 3 at all later time intervals. Pain scores from the incision site were similar among the three study groups. One year after surgery, 25% of patients reported having chronic donor site pain. The association of chronic donor site pain was significantly higher (P < 0.05) in groups 1 (33%) and 2 (37%) compared with group 3 (5%).

CONCLUSION

Low-dose morphine applied to the harvest graft site can reduce local pain, morphine use, and chronic donor site pain after cervical spine fusion surgery.

Postoperative analgesia for outpatient arthroscopic knee surgery with intraarticular clonidine and/or morphine

Both clonidine, an alpha(2) agonist, and morphine, an opioid agonist, provide enhanced patient analgesia after arthroscopic knee surgery when administered via the intraarticular (IA) route. Clonidine potentiates morphine analgesia in the animal model. We designed this study to determine whether clonidine or morphine results in better analgesia and whether their combination would provide superior analgesia to either drug alone. We evaluated 60 patients undergoing arthroscopic knee meniscus repair under local anesthesia with sedation. After surgery, patients were randomized into four IA groups: Group B received 30 mL 0.25% bupivacaine; Group BC received 30 mL 0.25% bupivacaine and clonidine 1 microg/kg; Group BM received 30 mL 0.25% bupivacaine and morphine 3 mg; and Group BCM received 30 mL 0.25% bupivacaine, clonidine 1 microg/kg, and morphine 3 mg. This study revealed a significant benefit from the individual IA administration of both clonidine and morphine. The combination of these drugs resulted in decreased postoperative pain and analgesic use, as well as an increased analgesic duration compared with either drug alone. We conclude that IA clonidine and morphine improved comfort compared with either drug alone in patients undergoing knee arthroscopy.

Use of clonidine in hernia patients: intramuscular versus surgical site

BACKGROUND AND OBJECTIVES

This study was designed to determine if administration of clonidine in hernia patients enhances analgesia. It was also designed to determine whether administration directly in the surgical site further improves the analgesia.

METHODS

A randomized, double-blinded study was undertaken at a tertiary care hospital. Forty-five outpatients undergoing unilateral inguinal hernia repair by one of two surgeons (D.P. or M.A.) under local anesthesia with monitored anesthesia care were evaluated. Patients were invited to participate in this investigation at the time of the preoperative surgical visit. Patients who had a contraindication to the use of clonidine or who refused repair under local anesthesia with sedation were excluded. Patients were randomized to one of three groups: (a) clonidine 0.5 microg/kg intramuscularly and saline in the surgical site (mixed with the local anesthetic); (b) clonidine 0.5 microg/kg in the surgical site and saline intramuscularly; or (c) saline in both the surgical site and intramuscularly. The outcome measures included visual analog pain scores twice in the hospital, pain scores at rest and with movement 24 hours postoperatively, the time to first analgesic, and total analgesic requirement.

RESULTS

The pain scores were lower in both clonidine groups at 2 hours postoperatively than in the control group (P < .03). No difference was observed with respect to the time to first analgesic, 24-hour analgesic use, or 24-hour pain scores among the groups.

CONCLUSIONS

When clonidine is administered to patients undergoing hernia repair, the 2-hour pain scores are lowered. No difference was exhibited when clonidine was administered intramuscularly or directly into the hernia site.

Postoperative analgesia with controlled-release oxycodone for outpatient anterior cruciate ligament surgery

Reconstruction of the anterior cruciate ligament (ACL) of the knee is associated with a considerable degree of postoperative pain. Although immediate-release oral opioids are usually effective in relieving moderate to severe pain, they must be given every 4-6 h. A controlled-release (CR) formulation of oxycodone maintains therapeutic opioid concentrations for a more prolonged period, thus providing sustained pain relief. We designed this study to determine whether CR oxycodone is more effective and clinically acceptable than immediate-release oxycodone for managing pain after ambulatory ACL repair surgery. All patients received a standard general anesthetic and postoperative analgesic regimen with one of three oxycodone dosing regimens: oxycodone 10 mg every 4 h as needed, oxycodone 10 mg every 4 h, and CR oxycodone 20 mg every 12 h. Rescue analgesic consisted of oxycodone 5 mg every 6 h as needed. At 24, 36, 48, 60, and 72 h, there was a difference in pain scores among the groups (P < 0.0001); there was less pain in the CR oxycodone group. At most times, the fixed-dose group had lower pain scores than the as-needed group. The sedation scores were significantly different at 12 h (P < 0.02) and at 24, 36, 48, 60, and 72 h (P < 0.0001); the patients were more alert in the CR oxycodone group. The 72-h consumption of oxycodone was less in the CR oxycodone group (P < 0.0001). The patients had less sleep disturbance (P < 0.0001), were more satisfied (P < 0.0001), and experienced less vomiting (P < 0.02) in the CR oxycodone group compared with the other two groups. In conclusion, using CR oxycodone in the immediate 72 h after ambulatory ACL surgery provides more effective analgesia with less sedation, sleep disturbance, and postoperative vomiting compared with oxycodone prescribed on either a fixed dose or as-needed schedule.

IMPLICATIONS

A controlled-release formulation of oxycodone in patients undergoing anterior cruciate ligament repair on an ambulatory basis provides significant analgesic benefit and a lowering of side effects compared with either fixed-dose or as-needed oxycodone regimens.