Intrathecal morphine analgesia in idiopathic scoliosis surgery: does sex or racial group affect optimal dosing?

BACKGROUND: We previously determined the intrathecal morphine optimal dose to maximize analgesia in patients undergoing idiopathic scoliosis surgery while minimizing adverse effects. Our purpose was to determine if this protocol was equally effective across sex and racial groups. METHODS: We studied 287 patients given a moderate dose of intrathecal morphine of 9 to 19 µg/kg (mean 14 µg/kg): 240 female and 47 male patients and 224 White (W) and 63 African-American (AA) patients. Factors analyzed included postoperative visual analog pain scores (VAS), time to first opioid dose, total morphine over the first 48 hours, and postoperative complications of respiratory depression requiring pediatric intensive care unit (PICU) admission, nausea/vomiting and pruritis. RESULTS: For female and male patients, mean VAS pain scores in postanesthesia care unit (PACU) were 0.48 ± 1.14 and 0.56 ± 1.16, mean times to first opioid dose were 16.65 ± 4.38 and 16.72 ± 4.97 hours, and total morphine over the first 48 hours were 1.49 ± 0.53 and 1.49 ± 0.58 mg/kg, respectively. Respiratory depression and PICU admission occurred in 10 of 240 female (4.1%) and 3 of 47 male (6.4%) patients. Minor complications of nausea/vomiting and pruritis occurred in 78 of 240 female (31.7%) and 12 of 47 male (25.5%) patients. For W and AA patients, mean VAS pain scores in PACU were 0.48 ± 1.10 and 0.46 ± 1.13, mean times to first opioid dose were 16.53 ± 3.77 and 17.12 ± 6.05 hours, and total morphine over the first 48 hours were 1.54 ± 0.53 and 1.30 ± 0.53 mg/kg, respectively. Respiratory depression and PICU admission occurred in 9 of 224 W (4.0%) and 4 of 63 AA (6.3%) patients. Nausea/vomiting and pruritis occurred in 77 of 224 W (34.4%) and 11 of 63 AA (17.5%) patients, respectively. CONCLUSIONS: Intrathecal morphine results in safe and effective for postoperative pain relief in patients undergoing surgery for idiopathic scoliosis irregardless of sex or race. LEVEL OF EVIDENCE: III, retrospective comparative study.

Continuous intravenous morphine infusion for postoperative analgesia following posterior spinal fusion for idiopathic scoliosis.

STUDY DESIGN: A retrospective study of postoperative pain management. OBJECTIVE: Evaluate the efficacy and safety of continuous intravenous morphine infusion for postoperative pain management in patients with idiopathic scoliosis (IS) undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). SUMMARY OF BACKGROUND DATA: Postoperative pain is a common problem following surgery for IS. There are no published reports regarding the use of a continuous intravenous morphine infusion for this patient population. METHODS: We retrospectively reviewed data regarding 339 consecutive patients with IS who underwent PSF and SSI between 1992 and 2006. All patients received intrathecal morphine after the induction of general anesthesia. Following surgery, preordered morphine infusion (0.01 mg/kg/h) was started at first reported pain. The infusion rate was titrated based on vital signs, visual analog scale (VAS) pain scores (0-10), and clinical status. It was continued until patients were able to take oral analgesics. We reviewed intrathecal morphine dosage, VAS pain scores through the third postoperative day, interval to start of morphine infusion, total morphine requirements in the first 48 hours, and any adverse reactions (nausea/vomiting, pruritus, respiratory depression, and pediatric intensive care unit admission). RESULTS: Mean intrathecal morphine dose was 15.5 +/- 3.9 microg/kg and mean interval to start of the intravenous morphine infusion was 17.5 +/- 5 hours. Mean VAS pain scores were 3.1, 4.5, 4.5, and 4.6 at 12 hours, 1, 2, and 3 days after surgery, respectively.The total mean morphine dose in the first 48 hours postoperatively was 0.03 +/- 0.01 mg/kg/h. Total morphine received was 1.44 +/- 0.5 mg/kg. Nausea/vomiting and pruritus, related to the morphine infusion occurred in 45 patients (13.3%) and 14 patients (4.1%), respectively. No patients had respiratory depression or required Pediatric Intensive Care Unit admission. CONCLUSION: A low frequency of adverse events and a mean postoperative VAS pain score of 5 or less demonstrate that a continuous postoperative morphine infusion is a safe and effective method of pain management in patients with IS following PSF and SSI.

Intrathecal morphine for postoperative analgesia in patients with idiopathic scoliosis undergoing posterior spinal fusion.

STUDY DESIGN: A retrospective study of postoperative pain management with intrathecal morphine. OBJECTIVE: Identify the dosing regimen of intrathecal morphine that safely and effectively provides postoperative analgesia with minimal complications in patients with idiopathic scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). SUMMARY OF BACKGROUND DATA: Postoperative pain after surgery for idiopathic scoliosis is a concern. Intrathecal morphine has been used to decrease pain. However, the most appropriate dose has not been determined. METHODS: We retrospectively analyzed 407 consecutive patients with idiopathic scoliosis who underwent PSF and SSI at our institution from 1992 through 2006. Patients were divided into 3 groups based on the intrathecal morphine dose: no dose (n = 68); moderate dose of 9 to 19 microg/kg, mean 14 microg/kg (n = 293); and high dose of 20 microg/kg or greater, mean 24 microg/kg (n = 46). Data included demographics, Wong-Baker visual analog scale postoperative pain scores, postoperative intravenous morphine requirements, time to first rescue dose of intravenous morphine, and postoperative complications of pruritus, nausea/vomiting, respiratory depression, and pediatric intensive care unit (PICU) admission. RESULTS: The demographics of the 3 study groups showed no statistical differences. The mean Wong-Baker visual analog scale pain score in the post anesthesia care unit was 5.2, 0.5, and 0.2, and the mean time to first morphine rescue was 6.6, 16.7, and 22.9 hours, respectively. In the first 48 postoperative hours, respiratory depression occurred in 1 (1.5%), 8 (2.7%), and 7 (15.2%) patients, whereas PICU admission occurred in 0 (0%), 6 (2%), and 8 (17.4%) patients, respectively. The majority of PICU admissions were the result of respiratory depression. Frequency of pruritus and nausea/vomiting was similar in all 3 groups. CONCLUSION: Intrathecal morphine in the moderate dose range of 9 to 19 microg/kg (mean 14 microg/kg), provides safe and effective postoperative analgesia in the immediate postoperative period for patients with idiopathic scoliosis undergoing PSF and SSI. Higher doses did not result in significantly better analgesia and had a greater frequency of respiratory depression requiring PICU admission.

Multi-slice CT angiography for arterial evaluation in the injured lower extremity.

BACKGROUND: With the evolution of multi-slice helical computed tomographic angiography (MCTA), the optimal imaging modality for arterial injury in the traumatized lower extremity has been challenged. The objective of this study was to evaluate the ability of MCTA to detect arterial injury in the traumatized lower extremity. Our hypothesis was that MCTA is a sensitive and specific test for the non-invasive evaluation of lower extremity arterial injury. METHODS: After Institutional Review Board approval, we reviewed all patients at our Level I trauma center who sustained lower extremity trauma and underwent initial evaluation by MCTA over a 3-year period ending in February 2005. MCTA accuracy was tested against a gold standard of operative intervention, duplex ultrasonography, catheter-based angiography, or clinical follow-up. RESULTS: Sixty-three MCTAs were performed in 59 patients. MCTA was diagnostic in 62 of the 63 scans (98.4%). The mechanism was penetrating in 45.8%. Lower extremity fractures were present in 38.7% of patients studied. There were 22 positive studies. Out of this group, 19 were confirmed at operation and 3 were managed non-operatively. In the 19 injuries confirmed in the operating theater, there were 5 superficial femoral, 2 profunda, 10 popliteal, 1 posterior tibial, and 1 injury to all 3 mid-calf arteries. There were two injuries below the trifurcation managed non-operatively and there was one popliteal occlusion with distal reconstitution that was confirmed by duplex and managed non-operatively because of patient refusal of surgery. Forty studies were negative for arterial injury, with clinical follow up available in 89.5%, for a mean of 48.2 days (range, 5-287 days). No missed injuries were identified during the follow-up period. MCTA was non-diagnostic in 1 patient (1.6%), secondary to artifact from retained missile fragments. MCTA achieved 100% sensitivity and 100% specificity in detecting clinically significant arterial injury. CONCLUSION: MCTA is a sensitive and specific non-invasive imaging modality for arterial evaluation in the injured lower extremity that may replace catheter-based angiography in most patients.