Session II Foot and Ankle
*Postoperative Analgesia After Operative Repair of Calcaneus Fractures - An Outcome Study Comparing Morphine Alone with Morphine and One-shot Perioperative Sciatic Nerve Blockade
Jeremy O. Cooper, MBChB, FANZCA, Stephen K Benirschke, MD, Bruce J Sangeorzan, MD, Christopher M. Bernards, MD, W. Thomas Edwards, PhD, MD
University of Washington, Harborview Medical Center, Seattle, WA
Purpose of the study: Calcaneus fracture repair generates severe postop pain. We aimed to compare two kinds of postop pain relief: morphine alone vs. morphine and one-shot perioperative sciatic nerve blockade (SNB). We also compared preop vs. postop blocks to investigate any preemptive analgesia effect.
Methods and Materials: Following human subjects committee approval and written informed consent, thirty patients undergoing internal fixation of calcaneus fractures were studied. Anesthesia was induced with 1-4 mcg /kg fentanyl and thiopental 4-7 mg/kg, and maintained with nitrous oxide/oxygen and isoflurane 0.5-2.5% (end tidal concentration). No opioid was used for maintenance anesthesia. Patients were randomized blindly into three groups. All groups had IV PCA morphine for postop analgesia. Group I had no SNB. Group 2 had one shot SNB performed after induction prior to surgery. Group 3 had SNB performed after surgery prior to anesthesia emergence. Nerve blockade using the Labat approach was with 25cc 1/2% bupivacaine (with epinephrine) after nerve location via peripheral nerve stimulation. Patients with uncontrollable pain received ketorolac as rescue medication. Data collected included morphine use in 48 hrs, visual analogue pain scores (VAPS) (0-l00mm) over 24 hrs, patient satisfaction, block duration, patient state of alertness in the Recovery Room (RR). Statistical analysis was performed using ANOVA, repeated measures ANOVA, and Fishers exact test. A p-value of 0.05 was considered significant.
Results: Twenty-eight patients successfully completed the study. One block failed. One patient did not complete the protocol. There was no morbidity from the anesthesia or the sciatic nerve blocks. Mean surgical time was 4.4 hours. Sciatic nerve blockade conferred better quality analgesia with fewer side effects than did PCA morphine alone (Table 1). Patient satisfaction was higher in groups 2 and 3. Post surgical block was preferred by patients. Preemptive analgesia effects of sciatic nerve blockade could not be shown. Intravenous ketoralac was effective as a rescue medication.
Conclusions: Patients having operative repair of calcaneus fractures experience severe pain. One-shot sciatic nerve block at the end of surgery confers significant benefits to these patients. Intravenous ketorolac is successful as rescue medication should pain become difficult to treat.
| SPI | GP2 | GP3 | |
| Morphine RR (mg) | 36.7 (6.9) | 3.6 (1.30) * | 4.8 (1.7)* |
| Morphine 1st 8 hrs. | 76.5 (8.5) | 32.1 (9.2)* | 19.1 (7.2)* |
| Morphine 24 hrs. | 170.4 (16.6) | 180.0 (36.5) | 151.6 (39.7) |
| Morphine 48 hrs. | 273.5 (36.0) | 306.6 (76.2) | 307.3 (82.2) |
| % Patients stuporous RR | 50 | 0* | 0* |
| HRSVAPS>40 | 23 | 7* | 6* |
| HRSVAPS>50 | 19 | 3* | 0* |
| Ketorolac rescues | 2/10 | 3/8 | 2/10 |
All values are mean +/-se.