Effect of fundoplication on the gastric emptying of liquids

Effect of different types of fundoplication on the gastric emptying of liquids and gastric compliance in rats

BACKGROUND/PURPOSE

The aim of this study is to evaluate the early and late effects of partial fundoplication (PFp) and total fundoplication (TFp) on gastric emptying (GE) and on gastric compliance (GC) in rats.

METHODS

One hundred fifty-nine male Wistar rats, 6 to 8 weeks of age and weighing 150 to 250 g underwent sham operation, PFp or TFp. They were randomly divided into early group (group E) and late group (group L), evaluated on the 7th and 28th postoperative days, respectively. Gastric emptying studies were performed with and without short-term induction of GE delay.

RESULTS

Gastric emptying studies: In group E, TFp altered gastric retention when compared with sham subgroup in rats with GE delay. In group L, neither PFp nor TFp produced changes in GE. Gastric volume-gastric compliance studies: In group E, only TFp reduced significantly gastric volume, but both PFp and TFp caused a significant decrease in GC. A trend toward normalization of gastric volume and GC was perceived in group L. Partial fundoplication did not change the intragastric pressure response in either group E or group L. Total fundoplication increased the intragastric pressure significantly in group E, but this difference disappeared on the 28th postoperative day.

CONCLUSIONS

Partial fundoplication induces less change in gastric motor physiology than TFp. These findings provide background to explain some differences in the postoperative course after PFp and TFp.

Postfundoplication Complications in Children

The optimal "treatment" of postfundoplication complications is preoperative prevention of them. Nonreflux causes of the symptom prompting surgery should be carefully eliminated preoperatively. Failure to respond to optimal powerful antireflux pharmacotherapy suggests that GERD was not the cause of symptoms. Neurologic or respiratory disease, delayed gastric emptying or retching, short esophagus, and esophageal dysmotility may predispose patients to complications, and may require careful tailoring of the fundoplication. The optimal antireflux surgery, with a wrap neither too loose nor too tight, may require a nadir lower esophageal sphincter pressure of more than 5 mm Hg to prevent reflux, but less than some value to prevent dysphagia. This latter value may be approximately 10 mm Hg, but depends on swallowing parameters such as peristaltic pressure, lower esophageal sphincter opening diameter, swallowed bolus diameter, and other considerations. Infants may require a gastrostomy tube for venting because of their lower gastric compliance to deal with swallowed air. Children with delayed gastric emptying may benefit from pyloroplasty, but this is debated. When complications occur, re-evaluate the diagnosis and the competence of the fundoplication with barium fluoroscopy, endoscopy with histology, pH probe, and other modalities as indicated. Initially try conservative management of the patient's complications, including dietary and feeding modifications. Give a trial of antireflux pharmacotherapy for recurrent reflux or pharmacotherapy directed at the specific side-effect of the fundoplication if one is present. Consider endoscopically dilating a persistently tight wrap or surgically revising the fundoplication if it is suggested by the evaluation.

Pyloroplasty improves long-term gastric emptying in rats undergoing fundoplication

BACKGROUND

Conflicting reports exist regarding the permanence of improved gastric emptying (GE) after fundoplication for gastroesophageal reflux in children.

METHODS

Changes in gastric volume (GV) and GE of a radiolabeled mixed meal induced by a Nissen fundoplication (NF) were compared with those with a NF plus pyloroplasty (NF + P). GE was measured preoperatively, 15 and 30 days postoperation, in 24 Sprague-Dawley rats; 12 had NF alone, and 12 had NF + P Results were expressed as percent gastric retention at 90 minutes (GR90). GV was measured at the same time periods in 20 additional rats.

RESULTS

NF rats had enhanced GE with reduction of preoperative GR90 from 37.6% to 23.7% at 15 days (P < .05); however, at 30 days the GR90 increased to 34.3%. NF + P rats had enhanced GE with reduction in GR90 from 37.2% to 20.8% at 15 days (P< .05), which persisted at 30 days (20.4%). Mean GV decreased from (1.36 mL/100 g body weight) preoperation to 0.86 at 15 days (P< .05) at 15 days in the NF group, and returned to 1.29 at 30 days. Mean GV decreased from 1.36 to 0.91 at 15 days in the NF + P rats and persisted at 0.90 at 30 days.

CONCLUSION

In the rat model, NF enhances GE transiently, whereas NF + P produces long-term enhancement of GE.

Gastric emptying after fundoplication is dependent on changes in gastric volume and compliance

BACKGROUND/PURPOSE

Nissen gastroesophageal fundoplication (GEF) increases gastric emptying (GE); however, the duration and the mechanisms for this improvement in GE remain unclear. The aim of this study was to evaluate the effects of a GEF on GE of a mixed meal, and to determine the correlation between GE and changes in intragastric pressure (IGP) and compliance.

METHODS

Using a radiolabeled mixed meal, GE was measured preoperatively 15 and 30 days after operation in 24 Sprague-Dawley rats divided into SHAM and GEF groups. Results were expressed as percent gastric retention at 90 minutes (GRg90), and time to evacuate 50% of the isotope meal (T1/2). Changes in IGP and compliance were determined at the same time-points using a different set of 20 rats.

RESULTS

Fifteen days after surgery, GR90 and T1/2 in the GEF group were reduced significantly when compared with preoperative values but returned to near preoperative values 30 days postoperation. In contrast, rats from the SHAM group showed no change in GR90 and T1/2 at 15 days and 30 days postoperation. Immediately after GEF, maximal distension of the stomach resulted in pressures 65% higher than those recorded before operation (20.2 v 11.7 mm Hg; P< .05), which persisted on the 15th postoperative day (17.7 v 10.7 mm Hg; P<.05). On the 30th postoperative day, however, there was no difference in the IGP between rats undergoing GEF compared with those undergoing a SHAM operation (11.7 v 12.0 mm Hg; P < .05). Similarly, mean gastric compliance decreased significantly immediately after and 15 days after GEF, but returned to preoperative levels 30 days after the operation.

CONCLUSIONS

In a rat model, GEF produces a transitory increase in GE, which is related to a simultaneous decrease in gastric volume and compliance. However, 30 days after GEF, associated with an elevated IGP, gastric volume increases and GE returns to preoperative levels.

Gastric emptying procedures decrease the risk of postoperative recurrent reflux in children with delayed gastric emptying

PURPOSE

Although several centers often perform gastric emptying procedures (GEP) together with fundoplication for gastroesophageal reflux (GER) and delayed gastric emptying (DGE), the benefit of GEP is controversial. The present study addresses the question of whether adding a GEP in children with preoperatively diagnosed GER and DGE affects the recurrence rate of GER after Nissen fundoplication (NF).

METHODS

A retrospective chart review was performed on all children under the age of 16 years, operated on for GER from 1980 to 1997, who had a preoperative diagnosis of DGE, and at least 6 months of follow-up. Gastric retention of more than 50% of a radiolabeled meal at 90 minutes was considered DGE. Recurrent reflux was defined as reappearance of GER symptoms, confirmed by postoperative esophagram or 24 hours of pH monitoring.

RESULTS

Of the 183 patients with DGE, 92 were available for long-term follow-up. Of these, 20 had no gastric emptying procedure performed (no-GEP group) and 72 had a GEP performed together with an NF (GEP group). Groups were comparable as to age at operation, mean follow-up time, male to female ratio and prevalence of associated anomalies. A higher prevalence of neurological impairment (NI) was present in the GEP group (48.6% v20.0%). Mean preoperative gastric retention was significantly higher in the GEP group (69.9 +/- 1.3%) than in the no-GEP group (61.4 +/- 2.2%). No complications resulted from the GEP. Recurrent reflux rate was 18.1% in the GEP group (13 of 72) versus 35.0% (7 of 20) in the no-GEP group. Actuarial analysis disclosed a marginally significant difference in the rate of recurrent reflux between the groups (P = .057) and estimation of the relative risk showed a 1.94 increase of recurrent reflux risk in the no-GEP (0.89<RR<4.20).

CONCLUSIONS

Children with DGE, who did not have GEP, had twice the frequency of recurrent reflux as those who had a GER Preoperative screening for DGE, as well as operative correction of DGE at the time of fundoplication, is therefore recommended.

Long-term quantitative results following fundoplication and antroplasty for gastroesophageal reflux and delayed gastric emptying in children

BACKGROUND

The operative management of children with combined gastroesophageal reflux and delayed gastric emptying is controversial. This study measures the long-term follow-up of gastric emptying in children who have undergone gastroesophageal fundoplication combined with antroplasty.

METHODS

Fifteen randomly selected children with gastroesophageal reflux and scintigraphically demonstrated delayed gastric emptying underwent fundoplication and antroplasty. Each patient had another gastric emptying scintigraphic study performed an average of 3.6 years postoperation.

RESULTS

All patients reported improvement of their symptoms compared with before the operation, and none required further medical therapy for gastroesophageal reflux or experienced dumping syndrome. Eleven of the 15 patients had significant long-term improvement of their gastric emptying postoperatively. The mean percent of isotope meal remaining in the stomach at 90 minutes improved from 72% preoperatively to 40% postoperatively (P = 0.0005).

CONCLUSIONS

Gastric emptying in children with gastroesophageal reflux and delayed gastric emptying is significantly improved for several years in three-fourths of patients after fundoplication and antroplasty. Fundoplication and concomitant antroplasty are recommended for symptomatic children with documented gastroesophageal reflux and delayed gastric emptying.

Is a gastric drainage procedure necessary at the time of antireflux surgery?

BACKGROUND

Gastroesophageal reflux is part of a generalized foregut motility disorder, which may also include delayed gastric emptying. With persistence of gastroesophageal reflux, or the presence of complications, including recurrent aspiration syndrome and esophageal stricture formation, surgical correction may be indicated. It is uncertain whether a procedure to resolve delayed gastric emptying is indicated at this time as well.

METHODS

Sixty-seven children with proven gastroesophageal reflux had preoperative gastric emptying assessed using 99Technetium-Sn-colloid labelled milk. Delayed gastric emptying was defined as a gastric residual activity of more than 40% at 2 hours after feeding. The antireflux operation was a partial anterior fundoplication. Postoperative milk scans assessed the effect of surgery on gastric emptying.

RESULTS

Gastric emptying at 2 hours improved overall from a median of 22% before surgery to 17% after surgery. In 17 patients delayed gastric emptying was identified before surgery; in 15 of those it returned to within normal limits after surgery. In 50 children with normal gastric emptying before surgery (gastric residual activity at 2 hours 16%), 14 (28%) showed delayed gastric emptying in the postoperative scan.

CONCLUSIONS

Delayed gastric emptying is common in children who undergo surgery for gastroesophageal reflux disease. A partial anterior fundoplication antireflux operation improves gastric emptying to within normal limits in the majority (88%) in this group, rendering a synchronous gastric drainage procedure unnecessary.