An unusual case of clarithromycin associated ergotism.

A 41-year-old woman presented to the Emergency Department complaining of a 4-day history of worsening lower leg pain, pallor, and a sensation of coolness aggravated by exertion. Evaluation revealed severe lower extremity vasospasm. She recently had been prescribed clarithromycin for "flu-like" symptoms, and for many years had been taking a caffeine-ergotamine preparation for migraine headaches. Clarithromycin is known to interfere with ergotamine metabolism. This drug interaction is often not recognized. Ergot alkaloids are commonly used for migraine headaches and have vasoconstrictive properties. In a patient with ergotamine toxicity, these vasoconstrictive properties can lead to frank ischemia. We reviewed the literature for reports of ergotamine-associated ischemia and for reports of ergotamine toxicity caused by drug-drug interaction.

Comparison of staples vs suturing for securing central venous catheters.

OBJECTIVE: To determine whether skin staples can be used to secure central venous catheters as effectively as does suturing. METHODS: A prospective, randomized trial of techniques to secure a central venous catheter was performed in a medical school human anatomy laboratory using human cadavers. Central lines were secured to the upper left thorax using either standard suture material (000 silk) or skin staples (5.7 mm x 3.8 mm). Once secured, an upward force was applied to the hub of the catheter perpendicular to the skin. The amount of force needed to break the catheter hub free of the skin was measured in kg. A total of 10 measurements were made for each of 3 methods for securing the catheters (2 sutures, 2 staples, 4 staples). In addition, the site of catheter breakage was recorded. RESULTS: Those catheter hubs secured by 2 sutures required a mean force of 3.1 +/- 0.5 kg to cause breakage, and the break always occurred at the suture. Those hubs secured by 2 staples gave way at 3.0 +/- 0.3 kg (p = NS), while those secured with 4 staples gave way at 4.5 +/- 1.4 kg (p < 0.05). Although 1 hub did break, in all other stapled cases, the break occurred at the staple. CONCLUSIONS: Based on this cadaver model, use of staples appears to be as effective as suturing for securing central venous catheters. Further studies of safety and time for placement are needed.

Prehospital blood pressures: inaccuracies caused by ambulance noise?

Blood pressure measurements in a moving ambulance can be difficult to obtain. Sirens, engine noise, and road noise can all interfere with the accurate detection of a patient's blood pressure. This study was undertaken to determine the influence of ambulance noise and vibration on auscultated blood pressures. A model was developed that used dynamic pressures to simulate systolic Korotkoff sounds. Forty-nine emergency personnel were asked to obtain blood pressures using the model in both a quiet environment and in a moving ambulance. A total of 485 blood pressure measurements were obtained. Systolic pressures were randomized to two settings: 76 mm Hg and 138 mm Hg. Stationary readings were compared with moving readings using analysis of variance for repeated measures. Systolic blood pressure measurements obtained in the quiet environment averaged 133 +/- 5 mm Hg at the high setting, and 45 +/- 6 mm Hg at the low setting. Systolic blood pressure measurements obtained in a moving ambulance averaged 86 +/- 7 mm Hg at the high setting, and 41 +/- 7 mm Hg at the low setting. The average differences between quiet and moving measurements were 47 mm Hg at the "high" setting (P < .01) and 4 mm Hg at the "low" setting (P > .01). At physiological levels, blood pressures obtained in moving ambulances differ significantly from those obtained in a quiet environment, which may be caused by road noise and ambulance motion.