An algorithm for the control of nosocomial varicella-zoster virus infection

Inadvertent or uncontrolled introduction of varicella-zoster virus into the hospital environment occurs commonly and must be investigated in a systematic and efficient manner to minimize secondary spread to patients (particularly the immunocompromised) or hospital personnel. On the basis of a review of the literature and our practical experience with 11 such exposures to varicella-zoster virus during a 2-year period, we have developed a working algorithm for such investigations. Index cases most often are children, resident physicians, students, young nurses, and ancillary personnel, or adult patients with herpes zoster. A negative or uncertain past history of this infection is an unreliable predictor of susceptibility among the exposed and should be confirmed by serology tests or delayed hypersensitivity skin testing. An incubation-contagion timetable, coupled with a stratification of risk among the exposed, permits a prioritized response in dealing with an introduction of varicella-zoster virus. The preemployment screening of all hospital workers for susceptibility to varicella-zoster virus should be considered as a practical and cost effective policy.     

Effect of PEEP on the rate of thoracic duct lymph flow and clearance of bacteria from the peritoneal cavity

A nonvirulent strain of E. coli, type K¹²F-, that was labelled with chromium-51 was injected intraperitoneally. The thoracic duct was cannulated in the left side of the neck. Dogs were randomly divided into two groups. In Group A, six dogs were ventilated with a mechanical ventilator for 1 hour. They were then ventilated with PEEP (expiratory limb of the nonrebreathing system 10 cm below water level) for 1 hour, and finally ventilated without PEEP for another 30 minutes. In Group B, five dogs were initially ventilated with PEEP in the same manner employed in Group A for 1 hour, then were ventilated without PEEP for 1 hour, and finally were again ventilated with 10 cm PEEP for 30 minutes. Thoracic duct lymph was collected in 10 minute aliquots throughout the experiment.In Group A, when PEEP was instituted after a period of mechanical ventilation, there was significant diminution in the rate of lymph flow, but no significant change in bacterial clearance. When PEEP was discontinued, both lymph flow rate and bacterial clearance increased significantly. In Group B, when PEEP was removed, both lymph flow rate and bacterial clearance increased significantly. When PEEP was reinstituted, the rate of lymph flow significantly decreased, but the change in bacterial clearance was not significant.PEEP may exert a deleterious effect on the clearance of bacteria and particulate debris from the peritoneal cavity through the thoracic lymphatic vessels and should be used with caution in patients with abdominal sepsis.     

Adenomyomatosis of the gallbladder

Adenomyomatosis of the gallbladder is characterized by hyperplasia of the mucosa and hypertrophy of the muscularis which may result from a functional obstruction to the outflow of bile. The resulting increased intracystic pressure results in invagination of the mucosa through the muscularis as intramural diverticula which may be diffuse, segmental or localized. From a series of 1,500 patients who had cholecystectomies performed during a 10 year period, 9 patients presented with symptoms indistinguishable from calculous cholecystitis and were found to have a pathologic diagnosis of adenomyomatosis without other pathologic findings. The striking feature in this group of patients was the chronicity of the symptoms before surgery (mean 7.7 years). During this time, eight of the nine patients underwent repeated radiologic investigation of the upper gastrointestinal tract for frequent symptoms. Surgical treatment led to the disappearance of symptoms in eight of the nine patients and marked improvement in the remaining patient. The presence of adenomyomatosis in a patient presenting with a symptom complex similar to that of calculous cholecystitis is an indication for cholecystectomy.