Background and objectives: The purpose of this study was to determine whether intra-articular injection of bupivacaine, morphine, or a combination prior to surgery provided pain control after arthroscopic anterior cruciate ligament (ACL) reconstruction.
Methods: These data were collected as a two-stage prospective, randomized, blinded observer study. All patients received a standard general anesthetic, which included an intra-articular injection 20 minutes prior to incision. In phase I, three solutions were assigned randomly in a 60-mL volume. Group 1 was saline, group 2 was 0.25% bupivacaine, and group 3 was 0.25% bupivacaine with 1 mg morphine sulfate (MS). Phase II was identical to phase I in technique and had four groups. Group 1 was 0.25% bupivacaine, group 2 was 1 mg MS in saline, group 3 was 0.25% bupivacaine with 1 mg MS, and group 4 was 0.25% bupivacaine with 3 mg MS. All groups in phases I and II contained 1:200,000 epinephrine, freshly added. Pain scores were evaluated at 0, 30, 60, 90, 120, and 240 minutes postoperative using a visual analog scale. For pain scores of 5 or greater, 50 microg fentanyl was administered at 5-minute intervals until pain was controlled. After transition from phase I to phase II of the postanesthesia care unit (PACU), hydrocodone/acetaminophen tablets were used.
Results: Thirty patients were entered into phase I of the study. Both treatment groups (2 and 3) had significant (P < .05) pain reduction on arrival to the PACU. Group 3 had significantly (P < .05) reduced need for fentanyl during the PACU stay. Forty-nine patients entered phase II of the study. In phase II, group 3 had the lowest pain scores on arrival to the PACU. At 120 and 240 minutes, pain scores were lower in groups 3 and 4. Fentanyl and hydrocodone uses were significantly lower during the PACU stay in groups 3 and 4.
Conclusions: Presurgical injection of a solution of 0.25 % bupivacaine, morphine, and epinephrine provided pain control and decreased opioid use in the PACU. Increasing the morphine dose did not improve the clinical result.