Biomedical subjects

Shue-ren Wann

Publications and source records attributed to Shue-ren Wann.

3 recordsLinked to original sources

PubMed2005

Abbreviated duration of superheat-and-flush and disinfection of taps for Legionella disinfection: lessons learned from failure.

One medical center in southern Taiwan faced an outbreak of nosocomial Legionnaires' disease; a total of 81 suspected cases were detected during an 8-month period. Baseline environmental surveillance showed that 80% of the distal sites in intensive care units (ICUs) were positive for Legionella pneumophila. Superheat-and-flush was selected for hospital water supply disinfection because it required no special equipment, and it can be initiated expeditiously. We conducted 2 episodes of superheat-and-flush based on the published recommendations from the Department of Health, Taiwan; US Centers for Disease Control and Prevention; and American Society of Heating, Refrigerating, and Air-Conditioning Engineers. Both flushes failed to control colonization of Legionella in the hospital water supply. The rate of distal sites positive for Legionella in wards and ICUs was 14% and 66%, respectively, 10 days after the second flush. The effect of replacement of faucets and showerheads in ICUs appeared to be insignificant in colonization of Legionella. The application of superheat-and-flush for flush duration of 5 minutes was ineffective. Superheat-and-flush may not be economic for a large medical center because it could be costly and labor intensive.

Academic Medical Centers↗

PubMed2002

Pharmacologic defibrillation.

Ventricular fibrillation (VF) is generally sustained. The mechanism is, at least in part, caused by progressive accumulation of intracellular sodium and calcium ions during untreated ventricular fibrillation, which subsequently increases defibrillation threshold. Cariporide, a potent and specific inhibitor of the sodium-hydrogen exchanger, has been shown to reduce intracellular sodium and calcium concentration in the setting of myocardial ischemia and reperfusion. We hypothesized that cariporide would facilitate defibrillation from prolonged ventricular fibrillation in a rodent model of cardiac arrest and resuscitation. Fifteen Sprague-Dawley rats were randomized to receive bolus injections of cariporide or placebo in a dose of 3 mg/kg into the right atrium either 5 mins before or at 8 mins after onset of ventricular fibrillation. Ventricular fibrillation was electrically induced and untreated for 8 mins. Precordial compression together with mechanical ventilation was then started and continued for an interval of 8 mins before attempted electrical defibrillation. All but one placebo-treated animal were successfully resuscitated. Spontaneous defibrillation with restoration of circulation was observed in both cariporide pretreatment and treatment groups but in none of the placebo-treated animals. The duration of postresuscitation survival was significantly increased in animals pretreated with cariporide. Therefore, sodium-hydrogen exchanger inhibitors may provide new options in settings of cardiopulmonary resuscitation to facilitate defibrillation.

Animals↗

PubMed2002

Cariporide for pharmacologic defibrillation after prolonged cardiac arrest.

BACKGROUND: We hypothesized that cariporide, a sodium-hydrogen exchange inhibitor, would be as cardioprotective during the global myocardial ischemia of prolonged cardiac arrest as it is in settings of coronary occlusion. METHODS AND RESULTS: Fifteen Sprague-Dawley rats were randomized to receive bolus injections of cariporide or placebo in a dose of 3 mgxkg(-1) into the right atrium either 5 minutes before, or at 8 minutes after, onset of ventricular fibrillation. Ventricular fibrillation was electrically induced and untreated for 8 minutes. Precordial compression, together with mechanical ventilation, was then started and continued for an interval of 8 minutes prior to attempted resuscitation. All but one placebo-treated animal were successfully resuscitated. Spontaneous defibrillation with restoration of circulation was observed in both cariporide-pretreatment and post-treatment groups but in none of the placebo-treated animals. Postresuscitation cardiac index, end-tidal CO(2), mean aortic pressure, left ventricular systolic pressure, left ventricular end-diastolic pressure, and left ventricular contractile and lusitropic functions (dP/dt(40), and -dP/dt) were significantly less impaired after cariporide, especially in the pretreated group, compared to electrically defibrillated controls. Postresuscitation ventricular premature beats were significantly reduced after cariporide. The duration of post-resuscitation survival was significantly increased in animals pretreated with cariporide. CONCLUSIONS: Cariporide, when administered prior to and during cardiac arrest, improved both the success of resuscitation and postresuscitation myocardial function.

Animals↗