Analgesic efficacy of continuous intravenous magnesium infusion as an adjuvant to morphine for postoperative analgesia: a systematic review and meta-analysis.

BACKGROUND: The efficacy of perioperative intravenous magnesium administration on postoperative opioid use, opioid-related side effects (e.g., nausea and vomiting) and pain are uncertain, as randomized controlled trials on this topic have reported disparate results. The objective of this systematic review is to determine if perioperative magnesium reduces opioid use, opioid-related side effects, and postoperative pain. METHODS: An electronic search was conducted using the Library of Medicine's PubMed and EMBASE databases. Included studies consisted of randomized controlled trials in an adult population with a clearly defined comparison of perioperative intravenous magnesium administration to a control with a documented assessment of opioid usage and postoperative pain. Relevant data was abstracted from included studies. Pooled estimates for weighted mean difference (WMD) with 95% confidence intervals (CI) were obtained for our primary outcome (opioid usage) using the Cochrane Collaboration's RevMan version 4.2.7 (Cochrane Collaboration; Oxford, United Kingdom). WMD and odds ratios (OR) were calculated using a random effects model. RESULTS: The literature search ultimately yielded 22 trials, enrolling 1177 (599 magnesium, 578 control) patients, who were included in the analysis. A significant decrease in morphine usage by those patients who received magnesium was noted (WMD = -7.40; 95% CI: -9.40 to -5.41, p < 0.00001). Perioperative magnesium administration was not associated with a difference in postoperative nausea or vomiting (RR = 0.76; 95% CI: 0.52 to 1.09, p = 0.14). The pooled visual analog scores for pain at 4-6 hours after surgery were significantly less in those patients who received magnesium surgery (WMD = -0.67; 95% CI: -1.12 to -0.23, p = 0.003); however, there was no difference in pain scores at 20-24 hours after surgery (WMD = -0.25; 95% CI: -0.62 to 0.71, p = 0.17). CONCLUSION: Based on the results of this systematic review, perioperative intravenous magnesium may be a useful adjuvant for the management of postoperative pain providing analgesia through a different mechanism of action than that of opioids and would make a potential addition to a multimodal anlgesic treatment plan; however, the decrease in opioid use with perioperative magnesium infusion does not appear to be associated with a decresea in opioid-related side effects.

Diagnosis of orthopedic infection in clinical practice using Tc-99m sulesomab (antigranulocyte monoclonal antibody fragment Fab'2).

OBJECTIVE: The aim of the study was to analyze the use of Tc-99m-labeled antigranulocyte monoclonal antibody fragment Fab'2 (SMab, Leukoscan) in the diagnosis of acute osteomyelitis and articular prosthesis infection. One hundred seventeen patients (118 studies) have been included, 92 women and 25 men. Thirty-seven had a suspicion of osteomyelitis and 81 with suspicion of infection of a hip (35 patients) or a knee (45 patients) prosthesis. The mean age was 64 years. A 3-phase bone scan and a SMab scan were obtained in all patients. Antigranulocyte scans were obtained within 3 and 8 hours postinjection of 20 mCi (740 MBq) of Tc-99m-labeled antibody. Diagnosis of infection was based on bone biopsy in 8 cases and on at least 2 positive cultures in the remaining cases. Infection was ruled out with negative cultures or 1-year patient follow up with negative C-reactive protein and normal erythrocyte sedimentation rate. RESULTS: Sensitivity, specificity, accuracy, and negative predictive value of Tc 99m-SMab scintigraphy were: 75%, 95%, 87%, and 92% for long bone osteomyelitis and 80%, 89%, 87%, and 91% for articular prosthesis infection, respectively. Positive predictive values were 83% and 63%, respectively. CONCLUSION: Tc-99m-antigranulocyte monoclonal antibody fragment Fab'2 scintigraphy seems to be a useful method in the diagnosis of osteoarticular infection.