Evaluation of an inaccurate pulmonary artery catheter thermistor.

A previously undescribed complication involving PAC thermistor temperature readings is characterized in this study. The thermistor readings became falsely elevated after the PAC was immersed in water, increasing steadily to 17.6 degrees C above control temperature readings. The abnormality resolved when the PAC was removed from immersion. A survey of ICUs revealed that PAC thermistors are frequently used to monitor the body temperature of patients requiring PACs. Only seven (35 percent) of 20 surveyed ICUs using PAC thermistors routinely confirmed PAC estimates of body temperature with another thermometric device. Since erroneous temperature measurements can have profoundly deleterious effects on clinical management, routine validation of PAC thermistors should be considered.

Benign oncocytic endocrine tumor of the pancreas in a patient with polyarteritis nodosa.

An 8-cm mass in the tail of the pancreas was resected from a 40-year-old man with polyarteritis nodosa. The tumor cells contained abundant, finely granular, eosinophilic cytoplasm arranged in a gyriform pattern that suggested the tumor was an oncocytoma of the endocrine pancreas. Electron microscopy confirmed that the tumor was an oncocytoma by demonstrating tumor cell cytoplasm packed with mitochondria. Ultrastructural and immunocytochemical studies confirmed the neuroendocrine nature of the tumor by demonstrating dense-core, membrane-bound structures consistent with neurosecretory granules and neuron-specific enolase immunoreactivity. No immunoreactivity for insulin, glucagon, gastrin, somatostatin, or pancreatic polypeptide was found. No human chorionic gonadotropin alpha-chain immunoreactivity was detected. The patient is well without evidence of tumor five years after operation. The apparently benign behavior of the pancreatic endocrine oncocytoma reported here is in contrast to the malignant nature of another case reported recently.