R. Douglas McEvoy

Relationship between sleep patterns and human colonic motor patterns

BACKGROUND/AIMSnThe precise relationships among colonic motor patterns, depth of sleep, and awakening are incompletely understood. The aim of this study was to correlate human colonic motor patterns with sleep stage, nocturnal arousals, and waking.nnnMETHODSnWe monitored sleep and correlated sleep stage, arousals, and waking with pressures (area under curve and propagating contractions) recorded from the entire colon in 11 healthy volunteers.nnnRESULTSnPropagating contraction frequency (P = 0.01) and area under the curve (P = 0.001) were significantly reduced at night. There was a highly significant correlation between depth of sleep and suppression of area under curve (P = 0.001) and propagating contraction frequency (P = 0.0001). Propagating contractions were eliminated during slow-wave sleep. During rapid eye movement sleep, colonic pressure and propagating contraction frequency increased sharply to levels comparable with those found in stage 2 sleep. Transient arousal from stable sleep, with or without waking, was a potent and immediate stimulus for colonic propagating contractions.nnnCONCLUSIONSnSleep per se has a profound inhibitory effect on propagating and nonpropagating activity and is the major determinant of diurnal variation of colonic motility. Propagating contractions are eliminated in slow-wave sleep. Rapid eye movement sleep, arousals, and waking have immediate stimulatory effects on colonic motility.

Percutaneous biopsy of intrapulmonary mass lesions. Experience with a disposable cutting needle

This study investigated the diagnostic efficacy and safety of a percutaneous core biopsy technique in patients with undiagnosed intrapulmonary mass lesions. Eighty‐four consecutive biopsies were performed in 81 patients with intrapulmonary mass lesions. Follow‐up data permitted a final diagnosis in 79 of these 81 patients, which allowed an assessment of the accuracy of the technique. Fifty‐nine of 68 patients with malignant lesions were diagnosed by core biopsy (87% sensitivity) and nine of 11 with benign lesions (82% sensitivity). The complication rate was 21%. Malignant tumor cell‐type was predicted correctly from biopsy material in 60% of patients. It is concluded that core biopsy is a safe procedure if restricted to the investigation of intrapulmonary mass lesions, and is effective in the identification of malignant tumors. Its chief advantage over aspiration techniques is that the tissue core obtained permits a specific diagnosis in a high proportion of patients with benign lesions, thus reducing the need in these patients for continued observation or diagnostic thoracotomy.