Long-term response to subtotal colectomy in colonic inertia.

The purpose of this study was to determine the long-term outcome of patients who had previously undergone subtotal colectomy for severe idiopathic constipation at the University of Florida between 1983 and 1987. In addition, we aimed to determine whether preoperative motility abnormalities of the upper gastrointestinal tract are more common among those patients who have significant postoperative complications after subtotal colectomy. We evaluated 13 patients who underwent subtotal colectomy for refractory constipation between 1983 and 1987 at the University of Florida. Preoperatively, all patients exhibited a pattern consistent with colonic inertia as demonstrated by means of radiopaque markers. Each patient was asked to quantitate the pain intensity and frequency of their bowel movements before and after surgery. In seven patients an ileosigmoid anastomosis was performed, whereas in six patients an ileorectal anastomosis was used. Abdominal pain decreased after subtotal colectomy. Patients with abnormal upper gastrointestinal motility preoperatively experienced greater postoperative pain than those with normal motility regardless of the type of anastomosis. In addition, the number of postoperative surgeries was similar in those patients with abnormal upper motility compared to those with normal motility. Overall, the total number of bowel movements per week increased from 0.5 +/- 0.03 preoperatively to 15 +/- 4.5 (P < 0.007) postoperatively. The results of our study suggest that patients with isolated colonic inertia have a better long-term outcome from subtotal colectomy than patients with additional upper gastrointestinal motility abnormalities associated with their colonic inertia.

Assessment of gastric emptying using a low fat meal: establishment of international control values.

OBJECTIVE: The diagnosis of gastroparesis implies delayed gastric emptying. The diagnostic gold standard is scintigraphy, but techniques and measured endpoints vary widely among institutions. In this study, a simplified scintigraphic measurement of gastric emptying was compared to conventional gastric scintigraphic techniques and normal gastric emptying values defined in healthy subjects. METHODS: In 123 volunteers (aged 19-73 yr, 60 women and 63 men) from 11 centers, scintigraphy was used to assess gastric emptying of a 99Tc-labeled low fat meal (egg substitute) and percent intragastric residual contents 60, 120, and 240 min after completion of the meal. In 42 subjects, additional measurements were taken every 10 min for 1 h. In 20 subjects, gastric emptying of a 99Tc-labeled liver meal was compared with that of the 99Tc-labeled low fat meal. RESULTS: Median values (95th percentile) for percent gastric retention at 60, 120, and 240 min were 69% (90%), 24% (60%) and 1.2% (10%) respectively. A power exponential model yielded similar emptying curves and estimated T50 when using images only taken at 1, 2 and 4 h, or with imaging taken every 10 min. Gastric emptying was initially more rapid in men but was comparable in men and women at 4 h; it was faster in older subjects (p < 0.05) but was independent of body mass index. CONCLUSIONS: This multicenter study provides gastric emptying values in healthy subjects based on data obtained using a large sample size and consistent meal and methodology. Gastric retention of >10% at 4 h is indicative of delayed emptying, a value comparable to those provided by more intensive scanning approaches. Gastric emptying of a low fat meal is initially faster in men but is comparable in women at 4 h; it is also faster in older individuals but is independent of body mass.

Products of cyclooxygenase-2 catalysis regulate postoperative bowel motility.

Laparotomy involving manipulation of the small intestine causes injury, initiating an inflammatory cascade in the small bowel wall, which generates eicosanoids and proinflammatory cytokines. We have shown that ketorolac and salsalate, nonselective cyclooxygenase (COX) inhibitors, ameliorate postoperative small bowel ileus in a rodent model. Others have shown that interleukin-1 receptor antagonism improves postoperative gastric emptying. We examined whether inhibition of the proinflammatory cytokines, tumor necrosis factor alpha (TNFalpha) and interleukin-1 (IL-1), or selective blockade of cyclooxygenase-2 (COX-2), the COX isoform induced during inflammation, would accelerate postoperative small bowel transit in our model. Duodenostomy tubes were inserted into male Sprague-Dawley rats. One week later, animals were randomized to receive TNF-binding protein (TNF-bp), IL-1 receptor antagonist (IL-1ra), or saline (NS) prior to standardized laparotomy. Additional rats were gavaged preoperatively with a selective COX-2 inhibitor (NS-398) or NS. Small intestinal transit was measured as the geometric center (GC) of distribution of (51)CrO(4) at 30 min, 3 h, or 6 h (n = 5-9 rats/group) following laparotomy. Selective inhibition of COX-2 significantly increased postoperative small bowel transit compared to controls (GC 2.9 +/- 0.3 vs 2.2 +/- 0.1 at 30 min, GC 2.9 +/- 0.3 vs 2.5 +/- 0.2 at 3 h, and GC 3.3 +/- 0.3 vs 2.8 +/- 0.2 at 6 h, P < 0.05). In contrast, neither TNF-bp nor IL-1ra altered postoperative small intestinal transit in this model. Use of selective COX-2 inhibitors may accelerate recovery of postoperative bowel dysmotility without the undesirable effects (e.g., gastrointestinal irritation and anti-platelet effect) of nonselective COX inhibitors.

Role of alpha- and beta-calcitonin gene-related peptide in postoperative small bowel ileus.

Ablation of a-calcitonin gene-related polypeptide (CGRP) containing neurons with the afferent neurotoxin capsaicin improves postoperative foregut transit in a rodent model. Similarly, administration of a selective alpha-CGRP antibody or hCGRP((8-37)), a CGRP receptor antagonist, improves postoperative gastric emptying. Unlike the stomach, which contains only alpha-CGRP, the small bowel additionally contains beta-CGRP. The role of the latter in postoperative small bowel transit is unknown. The purpose of this study was to evaluate the effect of an alpha-CGRP antibody and hCGRP((8-37)) on postoperative small bowel transit. Male Sprague-Dawley rats underwent placement of duodenal catheters and were randomly assigned to 1 of 11 groups. Four groups were pretreated with 1% capsaicin. One week later, all animals underwent standardized laparotomy following administration of a control antibody or the alpha-CGRP mono-clonal antibody, or during infusion of hCGRP((8-37)) at varying doses. Small bowel transit was measured 25 minutes postoperatively. The alpha-CGRP antibody sped postoperative transit when given alone or in combination with capsaicin. In contrast, animals treated with hCGRP((8-37)) showed no significant improvement in postoperative transit, and the beneficial effect of capsaicin was blocked. Unlike their similar effects on postoperative gastric emptying, we found that hCGRP((8-37)) and the alpha-CGRP antibody had differing effects on postoperative small bowel transit. The reason for this is unknown but may be related to their differing specificities for alpha- and beta-CGRP.

Unusual presentation of hemoptysis in a 78-year-old with previous Nissen fundoplication.

A 78-year-old individual, who had a previous transthoracic Nissen fundoplication 20 years earlier, presented to our institution with hemoptysis. Initial workup included chest roentgenogram, upper gastrointestinal series, and upper endoscopy, all of which were nondiagnostic. A repeat upper endoscopy diagnosed a gastrobronchial fistula by revealing a large gastric ulcer that penetrated into the lung parenchyma. The patient underwent surgery for takedown of the fistula. One of the most common symptoms associated with gastrobronchial fistula is hemoptysis, although insidious cough, recurrent pneumonia, or gastrointestinal bleeding are also observed. The most useful diagnostic study is an upper gastrointestinal series, which must be read with a high index of suspicion. Gastrobronchial fistula is most commonly a long-term complication from hiatal hernia repair. The most frequently used procedure for repair of this disorder is the Nissen fundoplication. This can be done from either an abdominal or transthoracic approach. When the procedure is done such that the gastric wrap is left above the diaphragm, serious complications can occur. These include gastric ulceration, gastric herniation with gastric outlet obstruction, slippage or perforation of the wrap, and gastrobronchial fistula. Because of these serious complications, the Nissen fundoplication with the wrap left above the diaphragm should only be used in certain situations, such as obesity and shortened esophagus.

Long-term consequences after jejunoileal bypass for morbid obesity.

This study assesses the long-term results of jejunoileal bypass (JIB) in 43 prospectively followed patients whose surgical bypass remained intact. Follow-up was 12.6+/-0.25 years from JIB. Weight loss and improved lipid levels, glucose tolerance, cardiac function, and pulmonary function were maintained. Adverse effects such as hypokalemia, cholelithiasis, and B12 or folate deficiency decreased over time. The incidence of diarrhea remained constant (63% vs 64% at five years), while the occurrence of hypomagnesemia increased (67% vs 43% at five years, P < 0.05). Nephrolithiasis occurred in 33% of patients. Hepatic fibrosis developed in 38% of patients and was progressive. Overall, after more than 10 years, 35% of patients appeared to benefit from JIB as defined by alleviation of preoperative symptoms and the development of only mild complications (vs 47% at five years). On the other hand, irreversible complications appeared to outweigh any benefit derived from the JIB in 19% (vs no patients at five years; P < 0.01). In summary, patients with JIB remain at risk for complications, particularly hepatic fibrosis, even into the late postoperative period.

Gastrointestinal myoelectric activity in a child with gastroschisis and ileal atresia.

Gastroschisis is frequently associated with intestinal atresia and alterations in gastrointestinal function. The authors studied gastric and small bowel myoelectric activity in a child who had a complex course and prolonged inability to tolerate oral intake after staged repair of gastroschisis and an associated ileal atresia. The child remained unable to tolerate oral intake after repair of the atresia and was reexplored 3 months later to rule out a partial small bowel obstruction, with simultaneous placement of serosal electrodes on the stomach and proximal small bowel. Persistent gastric dysrhythmias were observed postoperatively, and the child was unable to tolerate gastrostomy tube feedings. Abnormalities were also seen in small bowel motility, including retrograde propagation of activity fronts of the migrating myoelectric complex. However, the intestine converted to a fed myoelectric pattern with tube feedings, and the child was subsequently able to tolerate feedings via a tube placed directly into the small bowel. The authors conclude that myoelectric recordings via implanted electrodes are safe and feasible in children, and may give information regarding underlying motility alterations. The ultimate clinical role of myoelectric recordings in treating children with suspected motility disorders will require further study.

Salsalate, morphine, and postoperative ileus.

BACKGROUND: Previously, we demonstrated that ketorolac, a nonsteroidal antiinflammatory drug (NSAID), prevented postoperative small bowel ileus in a rodent model. The aim of this study was to evaluate the effect of salsalate, an NSAID without antiplatelet effect, on postoperative ileus alone or in combination with morphine. METHODS: Forty-eight rats underwent placement of duodenal catheters and were then randomly assigned to one of eight groups (n = 6). Four groups had standardized laparotomy following drug administration, whereas 4 groups underwent the same treatment without laparotomy: control and morphine animals received 0.1 mL alcohol via the catheter, whereas salsalate and salsalate-plus-morphine animals received salsalate (15 mg/kg) dissolved in 0.1 mL alcohol. The animals also received 0.5 mg/kg morphine (morphine and salsalate plus morphine) or the same volume of saline (control and salsalate) subcutaneously. Transit was measured following the injection of a nonabsorbed marker via the duodenal catheter and is defined as the geometric center (GC) of distribution. An additional 20 rats had serosal electrodes placed on the jejunum, and were assigned to one of four treatment groups (control, salsalate, morphine, and salsalate plus morphine; n = 5 each group). Myoelectric activity was recorded until the reappearance of the migrating myoelectric complex (MMC) following laparotomy. RESULTS: Laparotomy and morphine independently reduced small bowel transit (P = 0.0006 and 0.006, respectively, by three-way analysis of variance [ANOVA]; GC 4.3 +/- 0.2 control versus 2.2 +/- 0.3 laparotomy versus 3.6 +/- 0.4 morphine), but morphine did not further worsen postoperative transit (GC 2.4 +/- 0.4; P = 0.42). Although salsalate did not alter baseline transit, pretreatment improved postoperative transit (P = 0.0002; GC 3.6 +/- 0.4). This effect was lost with the addition of morphine (GC 2.7 +/- 0.2; P = 0.21). The MMCs returned earlier after laparotomy in salsalate-pretreated rats (63 +/- 18 minutes salsalate versus 160 +/- 12 minutes laparotomy; P < 0.01, one-way ANOVA). However, this effect was also lost in animals receiving morphine (106 +/- 16 min; P > 0.05). CONCLUSION: Salsalate improves postoperative small bowel motility in a rodent model; however, this effect is masked by morphine.

The effect of Roux-en-Y diversion on gastric and Roux-limb emptying in a rodent model.

BACKGROUND: The "Roux stasis syndrome" is characterized by symptoms of upper gut stasis following Roux-en-Y gastrojejunostomy (RG). Whether symptoms result from delayed gastric emptying, altered Roux-limb transit, or both has never been settled, partly because of the difficulty of measuring Roux-limb transit. The aim of this study was to develop a model to simultaneously quantitate Roux-limb transit and gastric emptying. METHODS: Rats underwent vagotomy and antrectomy with RG or Billroth II reconstruction (B-II). Gastrointestinal transit of a solid meal (Technetium-99m sulfur colloid-labelled egg white) was assessed 0.5, 1, and 1.5 hours postprandial (pp). Transit of a liquid marker (Na51-CrO4 injected through an efferent-limb catheter) was measured at 25 minutes pp. RESULTS: Solid gastric emptying was slower in RG than in B-II rats at 60 and 90 minutes pp. More of the solid meal and of the liquid marker was retained in the Roux limb than the efferent limb of the B-II at all time points (P < 0.05). CONCLUSIONS: In a rodent model, Roux-en-Y gastrojejunostomy is associated with delayed gastric emptying and slowed efferent-limb transit of solids and liquids.

Vasoactive intestinal peptide and substance P receptor antagonists improve postoperative ileus.

Octreotide, a somatostatin analogue that inhibits the release of most gut peptides, hastens the resolution of experimental postoperative ileus, suggesting that gut peptides mediate this process. We studied the role of two gut peptides involved in the control of normal gut motility, vasoactive intestinal peptide (VIP), and substance P (SP), in the initiation and maintenance of postoperative small bowel ileus in rats by preoperative administration of VIP and SP receptor antagonists, (VIP-ra and SP-ra). Thirty male Sprague-Dawley rats (300-350 g) underwent laparotomy. One half underwent placement of a duodenal catheter for transit studies while the other half had serosal electrodes placed on the proximal jejunum for myoelectric recordings. Six days later, animals were separated into three treatment groups of five each. Control animals were pretreated with ip saline, while the others received either VIP-ra or SP-ra prior to standardized laparotomy. Following abdominal closure, [Na51]CrO4 was injected into the duodenum and the animals were sacrificed 25 min later. The small bowel was then excised and divided into 10 equal segments. Small bowel transit was calculated as the geometric center of [Na51]CrO4 distribution. The interval until the return of migrating myoelectric complexes (MMCs) was determined in animals with intestinal electrodes. VIP-ra-treated rats demonstrated a 67% improvement in the geometric center of radiolabel relative to controls and SP-ra-treated rats had a 23% improvement (3.67 +/- 0.06 VIP-ra vs 2.69 +/- 0.09 SP-ra vs 2.20 +/- 0.09 control, P < 0.01). MMCs returned 180 +/- 17 min in controls vs 99 +/- 14 min in VIP-ra-treated rats (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Efferent limb myoneural and luminal continuity and postgastrectomy gastric emptying.

Delayed gastric emptying and altered upper gut transit or both are common following Roux-en-Y gastrojejunostomy and are thought to be due to altered efferent limb transit secondary to isolation of the Roux limb from the duodenal pacemaker. We postulated that preservation of myoneural continuity of the Roux limb with the duodenal pacemaker would enhance solid gastric emptying, while division of the afferent limb of a Billroth II gastrojejunostomy (B-II), isolating the efferent jejunal limb from the duodenal pacemaker, would slow gastric emptying. Solid gastric emptying was measured in 14 dogs, who then underwent gastric vagotomy and antrectomy. Eight animals were reconstructed with a Roux-en-Y gastrojejunostomy, preserving myoneural but not luminal continuity of the Roux limb with the afferent limb via a muscularis bridge, while six dogs underwent standard B-II gastrojejunostomy. Serosal electrodes were placed on the afferent and efferent jejunal limbs. Gastric emptying was restudied, with fed and fasted myoelectric recordings. The bridge was then divided to create a standard Roux, while the afferent limb was transected and reanastomosed just proximal to the gastrojejunostomy in the B-II dogs to isolate the efferent limb from the duodenal pacemaker, with repeat studies. Bridge dogs had delayed solid gastric emptying compared to their preoperative state, despite normal efferent limb motility.(ABSTRACT TRUNCATED AT 250 WORDS)

Erythromycin enhances gastric emptying in patients with gastroparesis after vagotomy and antrectomy.

We studied the effect of erythromycin on gastric emptying in nine patients with gastroparesis following truncal vagotomy and antrectomy, and assessed their clinical response to chronic oral erythromycin. Gastric emptying was evaluated using a solid-phase radio-labeled meal. Patients were studied after erythromycin 200 mg intravenously (N = 9) and after an oral suspension of erythromycin 200 mg (N = 7) each given 15 min after ingestion of the meal. Three parameters of gastric emptying were analyzed: half-emptying time (T1/2), area under the curve, and percent gastric residual at 2 hr. Nine patients were subsequently placed on oral suspension erythromycin 150 mg three times a day before meals (range 125-250 mg three times a day) and symptoms of nausea, vomiting, postprandial fullness, and abdominal pain were assessed before and after erythromycin. Intravenous erythromycin markedly accelerated the gastric emptying (all three parameters studied) of solids (P < 0.01) in seven of nine patients with postsurgical gastroparesis [baseline T1/2 154 +/- 15 min; after intravenous erythromycin, T1/2 56 +/- 17 min (mean +/- SEM)]. Oral erythromycin enhanced (P < 0.05) the gastric emptying rate (T1/2, area under the curve) in five of seven patients (baseline T1/2 146 +/- 16 min; after oral erythromycin, T1/2 87 +/- 20 min). Of the nine patients who were placed on oral maintenance erythromycin, three showed clinical improvement after two weeks. In summary, erythromycin significantly enhances gastric emptying in many patients with vagotomy and antrectomy-induced gastroparesis; however, only a small subset of patients respond clinically to chronic oral erythromycin.

Postoperative gastroparesis and tachygastria--response to electric stimulation and erythromycin.

BACKGROUND: The purpose of this study was to correlate clinical course, gastric emptying, and gastric myoelectric activity in a patient after gastric operation and to determine the effect of electric stimulation and the administration of erythromycin on the patient's gastric rhythm. METHODS: Daily myoelectric recordings were obtained through implanted gastric electrodes after truncal vagotomy and gastroenterostomy for an obstructing duodenal ulcer. RESULTS: The patient had acute postoperative delayed gastric emptying, accompanied initially by stomal edema but subsequently associated with persistent tachygastria. The gastric rhythm was only transiently slowed by multiple attempts at electroversion but appeared to respond dramatically to intravenous erythromycin therapy. Although delayed gastric emptying persisted on radionuclide gastric emptying studies, the patient slowly improved clinically with continued erythromycin therapy. CONCLUSIONS: Disturbances in gastric rhythm may accompany postoperative gastroparesis, although in our patient the dysrhythmias appeared to occur secondary to gastric outlet obstruction. Although his stomach could be paced, pacing was not effective in restoring a normal gastric rhythm. In contrast, intravenous erythromycin therapy was associated with rapid restoration of a normal gastric rhythm and slow improvement in gastric function.

Ketorolac prevents postoperative small intestinal ileus in rats.

The effect of ketorolac, a parenterally administered, nonsteroidal anti-inflammatory drug, was examined in a rat model of postoperative ileus. Small intestinal transit was measured by calculating the geometric center (GC) of distribution of 51CrO4. Laparotomy significantly delayed transit (GC: 2.2 +/- 0.2 after laparotomy versus 5.6 +/- 0.5 for unoperated controls, p < 0.01). The administration of ketorolac (1 mg/kg) improved the GC to 5.2 +/- 0.2 (p < 0.01), indicating normal intestinal transit after surgery in ketorolac-treated animals. Small intestinal myoelectric activity was recorded in rats with implanted electrodes. Animals treated with saline 2 hours postoperatively did not show return of the migrating myoelectric complex (MMC) in 183 +/- 25 minutes. In contrast, rats receiving ketorolac postoperatively had return of MMC activity in 59 +/- 18 minutes (p < 0.01). Preoperative ketorolac treatment reduced the duration of MMC inhibition after surgery from 197 +/- 55 minutes to 13 +/- 5 minutes (p < 0.05) when compared with saline. In summary, ketorolac hastens the return of MMC activity when given postoperatively. When ketorolac is administered preoperatively, it completely prevents the delay in intestinal transit and the inhibition of myoelectric activity seen in postoperative ileus. We concluded that ketorolac may be of benefit in the prevention and treatment of postoperative ileus.

Human gastric myoelectric activity and gastric emptying following gastric surgery and with pacing.

Postoperative gastric myoelectric activity, gastric emptying, and clinical course were correlated in 17 patients at high risk of developing gastroparesis after gastric surgery. In addition, an attempt was made to pace the stomach with an electrical stimulus and determine the effect of pacing on early postoperative gastric emptying. Gastric dysrhythmias (bradygastria, slow wave frequency < 2 cycles/min; tachygastria, slow wave frequency > 4 cycles/min) persisted beyond the first postoperative day in 6 patients (35%). Delayed gastric emptying was identified by a radionuclide meal in 15 patients (88%), but symptoms of gastroparesis developed in only 6 of 15 (40%). Patients with postoperative gastroparesis had more frequent dysrhythmias than asymptomatic patients (67% vs. 18%), but these differences were not significant, although we cannot exclude a type II statistical error. Gastric rhythm was entrained in 10 of 16 patients (63%). Pacing increased the gastric slow wave frequency (3.1 vs. 4.1 cycles/min; P < 0.01) but did not improve gastric emptying (gastric retention at 60 minutes, 86% +/- 6% for control and 90% +/- 2% for paced). In conclusion, gastric dysrhythmias do not appear to play a major role in the development of postsurgical gastroparesis. Although gastric rhythm could be entrained in the majority of patients, pacing did not improve gastric emptying overall.

Surgical approach to the obese patient.

Morbid obesity is a life-threatening disorder associated with medical and psychological complications. The failure of medical therapy has led to the development of a new surgical discipline called bariatric surgery, which has evolved over the past three decades. Initial techniques created malabsorption to produce weight loss. Due to complications, later techniques limited oral intake to produce weight loss. Currently, most bariatric surgeons perform either gastric bypass or gastric partition (vertical banded gastroplasty or vertical ring gastroplasty). However, other techniques are also being evaluated, including a modified intestinal bypass, gastric banding, and a new gastric balloon. Only with continued follow-up will we determine the ultimate risk/benefit ratio of these procedures and their place in the management of the morbidly obese. In the setting of an experienced multidisciplinary team committed to long-term follow-up, surgical therapy can be considered.

Preoperative and postoperative motility disorders of the stomach.

Improved technology has expanded the study and understanding of gastrointestinal motility. Although no clear cause and effect relation has been demonstrated, altered motility has been found in association with a variety of nonsurgical and postoperative settings. As this relation is better defined, perhaps patients who are at risk to develop complications of surgery can be better identified so that treatment can be tailored toward their specific defect. Technological advances can also be expected to provide new and more effective interventions in this expanding field.

Does selective vagotomy prevent delayed gastric emptying and altered myoelectric activity following Roux-en-Y gastrojejunostomy?

Delayed gastric emptying occurs frequently following Roux-en-Y gastrojejunostomy. The role of vagal denervation in the etiology of this "Roux-stasis syndrome" is controversial. This study evaluates the effect of selective vagotomy on gastric emptying and motility following Roux-en-Y. Four dogs underwent control gastric emptying studies. The animals then underwent selective vagotomy, antrectomy, and Billroth II gastrojejunostomy, with placement of serosal electrodes. Gastric emptying was assessed with simultaneous myoelectric recordings, and the animals were converted to Roux-en-Y, followed by repeat studies. Gastric emptying was unchanged following selective vagotomy, antrectomy, and Billroth II gastrojejunostomy (T 1/2: 132 +/- 18 min [SEM] versus 118 +/- 14 min control) but was markedly delayed following Roux-en-Y diversion (T 1/2: 286 +/- 44 min; p less than 0.01). All animals went into the fed pattern following Billroth II gastrojejunostomy (migrating myoelectric complex [MMC] interval: 326 +/- 6 min postprandial versus 92 +/- 5 min fasting; p less than 0.01), but no fed pattern was recognized in three of four animals following Roux-en-Y diversion (MMC interval: 68 +/- 12 min postprandial versus 62 +/- 1.5 min fasting; p = NS). In a canine model, selective vagotomy does not prevent delayed gastric emptying or myoelectric alterations following Roux-en-Y.