Effects of SK-896, a new human motilin analogue ([Leu13]motilin-Hse), on postoperative ileus in dogs after laparotomy

Gastric Motility Disorders in Dogs and Cats

Gastric motility disorders present both diagnostic and therapeutic challenges and likely are under-recognized in small animal practice. This review includes a comparative overview of etiopathogenesis and clinical presentation of gastric motility disorders, suggests a practical approach to the diagnosis of these conditions, and provides an update on methods to evaluate gastric motor function. Furthermore, management of gastric dysmotility is discussed, including a review of the documented effect of gastric prokinetics.

Motilin: from gastric motility stimulation to hunger signalling

After the discovery of motilin in 1972, motilin and the motilin receptor were studied intensely for their role in the control of gastrointestinal motility and as targets for treating hypomotility disorders. The genetic revolution - with the use of knockout models - sparked novel insights into the role of multiple peptides but contributed to a decline in interest in motilin, as this peptide and its receptor exist only as pseudogenes in rodents. The past 5 years have seen a major surge in interest in motilin, as a series of studies have shown its relevance in the control of hunger and regulation of food intake in humans in both health and disease. Luminal stimuli, such as bitter tastants, have been identified as modulators of motilin release, with effects on hunger and food intake. The current state of knowledge and potential implications for therapy are summarized in this Review.

Effect of prolonged general anesthesia with sevoflurane and laparoscopic surgery on gastric and small bowel propulsive motility and pH in dogs

OBJECTIVE

To determine if general anesthesia with sevoflurane and laparoscopic surgery changed gastric and small bowel propulsive motility or pH in dogs.

STUDY DESIGN

Prospective, controlled trial.

ANIMALS

Twelve, 19-24 months old, female, Treeing Walker Hound dogs, weighing 23-30 kg.

METHODS

Dogs were anesthetized for a median of 8.5 hours during another study to determine the minimum alveolar concentration of sevoflurane using a visceral stimulus. Gastric and small bowel motility were determined using a sensor capsule that measures pressure, pH and temperature. Gastric transit time and motility index were calculated. For 8/12 dogs, gastric motility, pH and transit time were measured. In 4/12 dogs, small bowel motility and pH were measured.

RESULTS

Anesthesia decreased gastric and small bowel motility but did not change luminal pH. Mean gastric contraction force decreased from median (range) 11 (8-20) to 3 (1-10) mmHg (p < 0.01) and gastric motility index decreased from 0.63 (0-1.58) to 0 (0-0.31; p = 0.01). Frequency of contractions did not change, 3.7 (1.6-4.4) versus 2.8 (0.1-5.1) contractions minute(-1) (p = 0.1). Gastric motility returned to normal 12-15 hours following anesthesia. Gastric emptying was prolonged from 12 (5.3-16) to 49 (9.75-56.25) hours (p < 0.01). Mean small bowel contraction force decreased from 34 (24-37) to 3 (0.9-17) mmHg (p < 0.02) and motility index decreased from 3.75 (1-4.56) to 0 (0-1.53; p = 0.02). Frequency of contractions did not change, 0.5 (0.3-1.4) versus 1.4 (0.3-4.6) contractions minute(-1) (p = 0.11). Small bowel motility returned within 2 hours after anesthesia. Laparoscopy did not result in changes to gastric or small bowel parameters beyond those produced by general anesthesia.

CONCLUSIONS AND CLINICAL RELEVANCE

The force of gastric and small bowel contractions decreased during sevoflurane anesthesia for laparoscopy. Although gastric motility returned to normal within 12-15 hours the impairment of gastric emptying lasted 30-40 hours, predisposing dogs to postoperative ileus.

New therapies in the treatment of postoperative ileus after gastrointestinal surgery

Postoperative ileus after gastrointestinal surgery results from many factors, including the effects of surgical trauma, anesthetic agents, hyperactivity of the sympathetic nervous system, local inflammatory reactions, and the use of opioids in the postoperative period. Postoperative ileus can lead to potential complications and may prolong patients' hospitalization, thereby leading to an increase in healthcare costs. There have been recent efforts to improve the understanding of the pathogenesis of postoperative ileus and to develop new treatments to prevent or minimize its occurrence. Here, we present a review of the factors related to the development of postoperative ileus and new therapies directed at its prevention.