Radiation Monitoring of an Isolation Room for 131I Therapy After the Patients Were Released.

PURPOSE: This study was performed to obtain a better understanding of the radiation environment in an I isolation room after the release of patients with metastasis from thyroid cancer that were treated with I doses ranging from 3.7 GBq (100 mCi) to 5.5 GBq (150 mCi) because there have not been any previous studies regarding the ambient radiation levels encountered in I isolation rooms after patients are released. METHODS: Ambient radiation levels and total and removable surface contamination levels were monitored for 3 weeks after each patient's release (and before the entry of the next patient). An area located 0.75 m along the corridor outside the room, the door, window, bedside, and the wall of the shower room were monitored with a Nal scintillation survey meter, which was used to obtain readings of the ambient radiation level in six directions, and the mean value for each area was recorded. In addition, areas that were suspected to be highly contaminated, including the toilet bowl, toilet sink, bed head, back of the bed, sink, trash box, and the patient's pillow, were monitored for total surface contamination with a GM survey meter. Furthermore, the toilet's U-bend, toilet sink, bed guard, table, shielding, sink plug, and door knob were swabbed for monitoring removable surface contamination, which was measured using a well counter. CONCLUSION: Ambient radiation monitoring in an I isolation room showed that there was negligible risk of harm in terms of the occupational radiation dose level after patients were released. The ambient radiation dose rate was higher near the door because the sink and trash box were located nearby. The toilet bowl, the toilet's U-bend, and the area around the sink exhibited heavy surface contamination, so these areas require cautious hygiene management.

[Biventricular pacing].

QRS widening has important clinical and prognostic implications in patients with chronic heart failure. Ventricular conduction abnormalities such as a left bundle branch block, cause ventricular dysynchrony and several hemodynamic disadvantages. The presence of ventricular dysynchrony results in abnormal wall motion, impaired ventricular contractility, decreased ventricular filling, and increased mitral regurgitation. Biventricular pacing has been recently proposed as an adjunct therapy for advanced heart failure in patients with ventricular conduction abnormalities. Biventricular pacing acutely increases the + dP/dt of left ventricle, the systolic blood pressure and the pulse pressure, prolongs the diastolic left ventricular filling time, shortens the mitral regurgitation duration, and reduces the pulmonary wedge pressure. The implantation of biventricular pacemaker results in improvements of the functional class, exercise capacity, quality of life, echocardiographic findings, and neurohormonal data. Although the indication for biventricular pacing has not yet established, patients with functional class III or IV and left bundle branch block or left ventricular conduction delay showing QRS duration > or = 150 ms are good candidates.