Surviving a stressful MIBI scan.

Dipyridamole/technetium sestamibi scans (more commonly known as MIBI scans, an acronym for methoxyisobutyl isonitrile) are used commonly for the diagnosis and risk stratification of coronary artery disease. Adverse events from MIBI scans are extremely rare. We present the case of a 64-year-old man who was successfully resuscitated after two asystolic episodes following dipyridamole infusion for a MIBI scan. The second asystolic episode occurred in the emergency department 40 minutes after the patient had been transferred from the Cardiac Stress Test Laboratory. To our knowledge, there are no previous reports of patients having two discrete asystolic episodes or an asystolic episode as delayed as we report after a MIBI scan. Our case illustrates why emergency physicians should be aware of the potential for asystole following MIBI scanning and why aminophylline, the antidote for dipyridamole, should be readily available in emergency departments that could see patients after pharmacologic stress testing. Patients who become asystolic following dipyridamole infusion likely require prolonged cardiac monitoring, given the potential for further episodes after periods of hemodynamic stability.

Pharmacokinetics/pharmacodynamics of levofloxacin 750 mg once daily in young women with acute uncomplicated pyelonephritis.

This pilot study was undertaken to characterise the pharmacokinetics, pharmacodynamics and potential clinical efficacy of levofloxacin 750 mg once daily for 5 days for treatment of women with acute uncomplicated pyelonephritis. Four women diagnosed with acute pyelonephritis were enrolled. Following pre-therapy specimen collection, an initial oral dose of 750 mg levofloxacin was administered. The mean pharmacokinetic parameters for the first dose were: maximum serum concentration (C(max)) 12.5+/-4.7 mg/L (range 5.6-16.0mg/L) (fC(max) 8.8+/-3.3, where f indicates the levofloxacin free or non-protein-bound fraction), area under the serum concentration-time curve (AUC) 85.4+/-14.1 mgh/L (range 66.2-96.8 mgh/L) (fAUC 59.8+/-9.9) and serum half-life (t(1/2)) 6.7+/-0.5h. Mean urine concentrations were 88.0+/-100mg/L at the 0-3 h collection, 307+/-143 mg/L at 3-6 h, 170+/-107 mg/L at 6-12 h and 85+/-8 mg/L at 12-24 h. Mean levofloxacin serum pharmacodynamics for infecting Escherichia coli were: C(max)/minimum inhibitory concentration (MIC) 323+/-185(fC(max)/MIC 226+/-129); and AUC/MIC 2339+/-830(fAUC/MIC 1647+/-579). Mean urine levofloxacin concentration/MIC ratios were: 900+/-1389 for 0-3 h, 12100+/-4950 for 3-6 h, 5922+/-3912 for 6-12 h and 2233+/-1037 for 12-24 h. Levofloxacin eradicated E. coli from the urine by 3-6 h after the first dose. Levofloxacin 750 mg once daily for 5 days has pharmacodynamics that support further evaluation of this regimen for treatment of women with acute uncomplicated pyelonephritis.