Sidney F. Phillips

Gastrointestinal transit after proctocolectomy with ileal pouch-anal anastomosis or ileostomy

Proctocolectomy with ileal pouch-anal anastomosis increases the frequency of stooling, perhaps due in part to the loss of an ileocecal or colonic braking effect on gastrointestinal transit. To assess whether colectomy with ileal pouch-anal anastomosis (IPAA) or with ileostomy accelerates gastrointestinal transit, we studied 16 IPAA patients (mean +/- SEM stool frequency, 8 +/- 1 stools/day), 5 patients after colectomy and Brooke ileostomy, and 8 healthy, unoperated controls (1 +/- 1 stools/day). Gastric emptying of liquids and small bowel transit of chyme were measured concurrently with a dual isotope technique. Gastric emptying was similar among all groups. In contrast, postprandial small bowel transit of the head of a duodenal marker was slowed, not accelerated, in IPAA patients (178 +/- 26 min) compared to Brooke subjects (80 +/- 32 min, P less than 0.05) and controls (75 +/- 15 min, P less than 0.01). Maximal filling of both the ileal pouch (341 +/- 19 min) and the ileostomy bag (348 +/- 12 min) occurred later than filling of the colon in controls (243 +/- 32 min, P less than 0.01). Overall stool frequency did not correlate with small bowel transit in the ileoanal patients, but the two ileoanal subjects with greatest stool frequency (11 and 18 stools/day) had the earliest arrival of marker at the pouch. In conclusion, removal of the colon markedly slowed small bowel transit in most patients, although it did not alter gastric emptying of liquids. Creation of an ileal pouch and ileoanal anastomosis further slowed transit of the head of the meal.(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution of Mesalamine Enemas in Patients With Active Distal Ulcerative Colitis

Mesalamine (5-aminosalicylic acid), a topically administered anti-inflammatory agent, is effective treatment by enema for distal ulcerative colitis; it lacks many of the side effects of orally administered sulfasalazine. In this study, we determined the colonic distribution of a 60-ml mesalamine enema in eight patients (five women and three men, 18 to 48 years old) with active distal ulcerative colitis that ranged from 12 to 40 cm proximal to the anal verge. On 3 consecutive days, each patient self-administered a 4-g (60-ml) 5-aminosalicylic acid enema that contained 3.7 MBq of [99mTc]technetium-sulfur colloid. Anterior and posterior images were obtained at 0, 30, 60, 120, and 240 minutes. During the 4-hour study period, all patients retained the enemas. The enemas spread to the sigmoid region in 24 of 24 studies, to the splenic flexure region in 22 of 24, and to the transverse colon in 1 of 24. Most of the enema was retained in the sigmoid colon. Therefore, we conclude that a 60-ml enema, when administered as recommended clinically, routinely flows retrograde as far as the splenic flexure but rarely spreads beyond this point. These results support the use of intrarectally administered 5-aminosalicylic acid for segmental colitis of the descending colon.

Effect of extrinsic denervation on muscarinic neurotransmission in the canine ileocolonic region

Abstract  To explore the hypothesis that denervation hypersensitivity increases ileocolonic motor activity after extrinsic denervation, we compared muscarinic neurotransmission in canine ileocolonic loops that were isolated and either extrinsically innervated or extrinsically denervated. We recorded ileal, ileocolonic sphincter (ICS) and colonic pressures, and colonic tone, compliance and relaxation during ileal distention. Muscarinic effects were probed by neostigmine, and minimally effective doses of muscarinic receptor antagonists. Denervation augmented ileal, ICS and colonic contractile activity; colonic high‐amplitude propagating contractions (HAPCs) were also augmented; colonic relaxation during ileal distention was abolished. Neostigmine induced HAPCs in both loop preparations. Pirenzipine (M1 antagonist) reduced ileal contractile activity in all loops and reduced colonic relaxation during ileal distention in innervated loops. Pirenzipine also reduced colonic tone and colonic HAPCs, more in denervated loops. Darifenacin (M3 antagonist) reduced ileocolonic contractile activity and tone more than did AF‐DX 116 (M2 antagonist) in all loops. Cholinergic receptor subtypes modulate different facets of ileocolonic motor activity in the canine ileocolonic region. Increased sensitivity at M1 muscarinic receptors may partly account for the effects of extrinsic denervation.

A continent ileostomy device.

The feasibility of achieving fecal continence by mechanical occlusion of an end-ileostomy is explored. Accordingly, progressive stomal occlusion with an indwelling occluding device was evaluated in four healthy patients with Brooke ileostomies. Pre-occlusion clinical and physiologic tests were done, including fat balance, intestinal transit time, ileal motility and absorption, ileal compliance, ileal radiography, and ileoscopy. Progressive stomal occlusion was then employed until periods of occlusion of 5 to 8 hours were achieved after 10 to 16 weeks. Pre-occlusion tests were then repeated. Patients mastered use of the occluding device rapidly, and the device achieved reliable stomal continence in each patient. Whereas ileal capacity was small initially, intermittent occlusion resulted in a large, capacious ileal reservoir. Fasting ileal motility was increased slightly by stomal occlusion, although intestinal transit during feeding was not altered. Also, ileal absorption of glucose, electrolytes, vitamin B-12, and fat were not changed, and ileal mucosa at the site of occlusion remained intact endoscopically. The authors concluded that chronic intermittent occlusion of a Brooke ileostomy with an indwelling stomal device achieved enteric continence without impairing intestinal function.

Limitations of implantable, miniature ultrasonic transducers to measure wall movement in the canine jejunum

BACKGROUND We used implantable miniature ultrasonic transducers to measure longitudinal distance, circumference, and wall thickness dynamically in vivo in canine jejunum. We hoped to differentiate circular from longitudinal smooth muscle contractions and to correlate physical measurements of change in distance within the jejunal wall with intraluminal manometry. MATERIALS AND METHODS In acute experiments at the time of celiotomy, longitudinal distances, circumferences, and wall thickness were measured directly and by ultrasonic transducers sewn to serosa and mucosa. Measurements were obtained with the intestine empty and after distention with air, water, or semisolid slurry. In chronic in vivo experiments in conscious dogs with indwelling ultrasonic transducers and intraluminal manometers, sonometric dimensions were correlated with manometric recordings. In acute experiments, sonometric measurements were similar to direct measurements. In chronic experiments in vivo, smallest ultrasonometric measurements of circumferences of the jejunum correlated in a phase-locked temporal manner with both highest intraluminal pressures and greatest wall thickness. RESULTS Longitudinal distances increased during decreases in circumference. Distances orad to the site maximal intraluminal pressure peaked at 0.58 +/- 0.04 s ( x +/- SEM) before, and those aborad to this point 0.42 +/- 0.04 s after attaining minimum circumferences. CONCLUSIONS Ultrasonic crystals can monitor geometric changes in the bowel wall with certain limitations, especially when obtained in vivo. Contraction of circular and longitudinal muscles, although phase-locked, do not appear to occur exactly synchronously in canine jejunum.