A comparison of ultrasound-guided and landmark-based approaches to saphenous nerve blockade: a prospective, controlled, blinded, crossover trial.

BACKGROUND: Blockade of the saphenous nerve is often used for surgeries below the knee. Depending on the approach, success rates vary widely ranging from 33% to 88%. In this prospective volunteer study, we compared 2 ultrasound-guided techniques, the modified vastus medialis and perifemoral saphenous nerve block with a below the knee field block. METHODS: Twenty volunteer adults, in a single-blinded, crossover, prospective trial underwent 3 different saphenous nerve blocks. The primary end point of block success was loss of sensation in the distal two-thirds distribution of the saphenous nerve. Secondary variables included time to perform the block, time to sensory loss, pain during block, and motor weakness. RESULTS: Compared with the below the knee field block success rate (30%), both the modified vastus medialis and perifemoral techniques had significantly higher success rates (80%, difference 50% with confidence interval [CI], 23%-77%, P = 0.009, and 100%, difference 70% with CI, 41%-91%, P < 0.001, respectively). However, the difference when comparing the perifemoral ultrasound technique against the modified vastus medialis ultrasound technique did not show significance (difference 20% with CI, -7% to 49%, P = 0.125). Also, no statistical differences were found with the other variables measured, except the perifemoral technique showed faster block performance times than below the knee field block (P = 0.007). CONCLUSION: In our prospective study, we have demonstrated that ultrasound-guided above the knee saphenous nerve blocks have higher success rates than a below the knee field block and are easily performed in a short amount of time.

Pacific partnership 2010: Anesthesia support aboard the USNS Mercy humanitarian civic assistance.

INTRODUCTION: The USNS Mercy has been integral in providing humanitarian and civic assistance as part of the Department of Defense's ongoing Combatant Commander Theater Security Cooperation Plans. The purpose of this study was to critically assess patient demographics and procedures performed to provide guidance for future missions. METHODS: A retrospective review was performed on a cohort of 825 surgical patients who underwent surgery during a 4-month period during Pacific Partnership 2010. Patient demographics, anesthesia exam findings, comorbidities, and surgical data were compared among the mission sites. RESULTS: Of the 825 patients, the mean age ranged from 39.7 to 24.7 with a statistical difference between Vietnam (39.7, p < 0.0087 for all tests) and the remaining sites. Poorer health by American Society of Anesthesiologist grading was noted in Vietnam (1.61) as compared to patients in Cambodia (1.21, p < 0.001) and Timor-Leste (1.40, p = 0.001). No difference in complication rates was noted. DISCUSSION: The reason for apparent differences in age or health status by site weren't clearly explained, but these differences had no bearing on surgical outcome. CONCLUSION: Analysis of anesthesia data compiled during Pacific Partnership 2010 provided meaningful data for future humanitarian efforts at these sites.

Coronary artery aneurysm and thrombosis following chronic ephedra use.

Ephedra, also known as Ma Huang, was commonly used to enhance athletic performance, "fat burning", and weight loss before its removal from the United States in April 2004 due to acute adverse health reactions including lethal arrhythmias, stroke, vasoconstriction, and myocardial infarction. We report the case of a 29-year-old patient with acute myocardial infarction, secondary to coronary artery aneurysms and thrombosis who reported use of Ma Huang, Xenadrine(r)RFA, and Hydroxycut at recommended dosages for a combined total of approximately 2 years. Other causes of coronary artery aneurysm and hypercoagulability were ruled out. Our case exemplifies the long-term (as opposed to acute) danger of ephedrine products and the first case of coronary artery aneurysm associated with its use.