Riboflavin intakes and status of morbidly obese females during the first postoperative year following gastroplasty

Eighteen women participated in a prospective study to assess the need for supplemental riboflavin after gastroplasty. Three groups of five patients received either a placebo or 0.6 or 1.2 mg riboflavin daily for up to 12 months, except during months 4 and 7 when all participants were given a "one-a-day" supplement containing 1.7 mg riboflavin. Dietary intakes of riboflavin decreased from 1.43 +/- 0.17 mg before the operation to 0.70 +/- 0.07 mg at 3 months, and then increased to 1.02 +/- 0.17 mg by 6 months. Even at 12 months, only 33% of the subjects had dietary intakes greater than or equal to 1.2 mg. All those with total intakes less than or equal to 1.7 mg at 3 months had impaired riboflavin status, as indicated by an erythrocyte gluthatione reductase activity coefficient greater than 1.40 and an erythrocyte riboflavin concentration less than 372 nmol/L. In contrast, 62% of the same subjects had urinary riboflavin excretion in the acceptable range. Supplemental intake of 1.7 mg riboflavin appeared to prevent tissue depletion in all subjects.

Pathogenesis of complications of percutaneous endoscopic gastrostomy. A lesson in surgical principles

In two comparable series of percutaneous endoscopic gastrostomy differing in only one technical detail, complications were significantly reduced by omitting traction on the gastrostomy tube to approximate the gastric to the abdominal wall. Radiologic studies show that traction shortened the tract (4.9 +/- 1.1 cm with traction, 11.6 +/- 2.3 cm without traction). In two patients with fasciitis, gross pericatheter leak of contrast into a short and patulous tract was observed. Tube extrusion and gastrointestinal bleeding from gastric ersion ulcers were eliminated when traction was not used. No peritonitis occurred as a result of not attempting to approximate the stomach to the abdominal wall. The data suggest that traction on the gastrostomy tube is not only unnecessary, but is the cause of many of the complications reported.

Effect of energy restriction on riboflavin retention in normal and deficient tissues of the rat

We investigated the effects of energy restriction on tissue riboflavin depletion and subsequent repletion of deficient tissues. Groups of male Sprague Dawley rats with average body weights between 268 and 275g were placed on energy-restricted diets consisting of 8g (31kcal or 130kJ) per day of a basal diet adequate in all other nutrients and either 12mg of riboflavin/kg or no added riboflavin. The ad libitum controls received additional energy as a mixture of sucrose, starch, and corn oil (10:3:1 by wt). No significant difference in the degree of riboflavin deficiency was detected between energy-restricted and ad libitum-fed rats as assessed by riboflavin concentrations in the liver and gastrocnemius and soleus muscles and by the erythrocyte glutathione reductase activity coefficient (EGRAC). Additional energy-restricted riboflavin-deficient rats were subsequently repleted by feeding either the supplemented basal diet with no additional energy or with ad libitum energy. Repletion of liver riboflavin concentration and reduction of the EGRAC values to control levels occurred regardless of energy intake. Muscle riboflavin concentrations were normal in the ad libitum-fed group but decreased in the energy-restricted rats despite 4 weeks of supplementation. The latter group had muscle riboflavin levels similar to those in the rats fed the riboflavin-deficient diet for 8 weeks. The results suggest that energy restriction impairs flavo-protein synthesis in muscle but not in the liver.

Plasma pyridoxal phosphate as indicator of vitamin B6 status in morbidly obese women after gastric restriction surgery

Plasma pyridoxal phosphate (PLP) concentrations were determined in 15 morbidly obese women before and after gastric restriction surgery for weight reduction. The subjects received a daily vitamin-mineral supplement containing 2 or 3 mg of vitamin B6 for 9 days before the operation and either a placebo or a multivitamin supplement containing 0.4, 0.8 or 2 mg of vitamin B6 for 3 months postoperatively. During the fourth month, all subjects received 2 mg of supplemental vitamin B6 per day. Dietary intakes of the vitamin were calculated from 3-day intake records kept by the subjects. Blood samples for PLP determination were obtained preoperatively and twice between weeks 4 and 8 and at 3 and 4 months postoperatively. The mean concentration of plasma PLP increased significantly from preoperation to 4 to 5 weeks postoperation and returned to the preoperative level by 6 to 8 weeks, with no further changes during the rest of the experimental period. There was no correlation between plasma PLP and either total or supplemental intakes of vitamin B6 at any of the time periods studied. Significant positive correlations were found between the preoperative and the first two postoperative plasma PLP levels (r = 0.93 and 0.67, p less than 0.001 and 0.005, respectively) and between the rate of weight loss and plasma PLP at 4-5 weeks and at 4 months postoperatively. Muscle PLP reserve may be mobilized during the early postoperative period and complicate the use of plasma PLP as a measure of vitamin B6 status.

Videoendoscopy for difficult anastomoses

To determine whether intra-operative videoendoscopy provides useful information on the integrity of gastrointestinal anastomoses, laboratory and clinical studies were undertaken. In the dog model, the videoendoscope was inserted per orum to visualize side-to-side (gastrojejunostomy) and end-to-end (jejunojejunostomy) anastomoses and to establish endoscopic criteria of normal anastomosis, verified by examination of the specimen. Technically faulty anastomoses were then constructed and inspected endoscopically to determine the signs of poor technique. In clinical application, the videoendoscope was used to inspect the anastomoses after low anterior resection, revision of gastric bypass, and choledochoduodenostomy. The laboratory results indicate that direct visualization of a defect in suture-line with the end-viewing endoscope is difficult, although indirect signs of trouble are helpful. Conversely, the appearance of a perfect anastomosis without any indirect signs of poor technique is accurate in the assurance of a trouble-free anastomosis. The best clinical use is in low anterior resection of the rectum and the worst is in choledochoduodenostomy. It is concluded that videoendoscopic inspection of anastomosis is only of limited help in determining the integrity of a difficult anastomosis, and much work is required to perfect both the instrument and technique before general use is recommended.

Prediction of post-cardiopulmonary bypass cardiac output

The ability to predict cardiac output (CO) before termination of cardiopulmonary bypass (CPB) allows identification of potential complications once the patient is off bypass. We have previously demonstrated that CO early after CPB can be reliably predicted by a plot of venous oxygen saturation at various flow rates on CPB, based on in-line monitoring of venous oxygen saturation. In this study, we evaluated a simplified technique for predicting CO with a series of 50 patients on CPB. When CPB weaning began, patients were normothermic, anesthetized, and paralyzed. Venous oxygen saturation and arterial blood flow were recorded. At low pump flow just before termination of CPB, the final venous oxygen saturation was recorded. Assuming a proportional relationship between venous oxygen saturation and arterial blood flow, CO early after CPB was predicted. The simplified CO prediction was compared with the thermodilution CO immediately after CPB. The simplified technique reliably predicted CO early after CPB compared with the thermodilution technique. The simplicity and reliability increase the clinical value of the CO prediction.

The role of tissue ischemia in the pathogenesis of anastomotic stricture

In a chronic dog model, colocolostomies with intact blood supplies were constructed with the circular stapler. By means of "tight" stapling, an ischemic suture line was induced (suture line blood flow reduced to less than 10% of baseline mucosal blood flow). Under these conditions, only one of 20 anastomoses resulted in stenosis at 1 month. Correctly stapled colocolostomies were then performed in bowels rendered ischemic by removal of all mesenteric arcades for 4 to 6 cm. Mucosal blood flow in such ischemic bowels was reduced to 30% and 16% of control, respectively, and suture line blood flow was as low as that of the tightly stapled anastomoses. Significant stenosis (more than 68% reduction of the lumen) was observed in the group with 6 cm of mesenteric clearance. In no dogs did peritonitis or colonic gangrene develop. Gross and histologic revascularization was evident when dogs were killed at 6 weeks. These findings suggest that it is ischemia of the bowel, rather than ischemia at the suture line itself, that leads to anastomotic stricture. In view of the known susceptibility of the human intestine to ischemia, the model may have overstated the degree of ischemia necessary to produce strictures in clinical practice. Since the induced acute ischemia did not persist in the chronic state, we conclude that it is the adequacy of collateral development that determines the outcome in this model.

The sources of recurrent hemorrhage during long-term sclerotherapy

The sources of recurrent hemorrhage during long-term sclerotherapy undertaken by a single surgeon were studied prospectively in a consecutive series of 53 patients for a period of 2 to 6 years. Recurrent hemorrhage, defined as upper gastrointestinal bleeding requiring transfusion or hospitalization or both, in the course of chronic sclerotherapy was investigated aggressively by means of endoscopy and the findings archived with videotape recording. In 24 patients 51 episodes of recurrent hemorrhage developed in the entire series. On the basis of endoscopic findings and serial comparison of videotape recordings, the most common source of recurrent hemorrhage was the original varices, which accounted for rebleeding in 18 patients. The risk of such bleeding was highest in the first month, diminishing thereafter until total variceal eradication. Rebleeding after eradication of varices was always from sources other than varices, as regenerated vessels were small and infrequent and never the source of bleeding. Continued sclerotherapy ultimately achieved total variceal eradication in 15 of 18 patients with variceal rebleeding. Sclerotherapy alone was successful in eradicating all varices in a total of 38 patients in this series, the mean time required being 13 +/- 4.1 months. Rebleeding from sources not amenable to sclerotherapy was treated with porto-azygos disconnection (6 patients) or distal splenorenal shunts (3 patients). There were 12 deaths: four attributed to hemorrhage (3 after surgery), five from liver failure, and three late deaths from causes not due to liver disease. Recurrent hemorrhage per se during the course of sclerotherapy may not be taken as a sign of treatment failure but must be vigorously investigated, since findings profoundly affect management and outcome.

Endoscopic measurement of gastric mucosal blood flow by laser Doppler velocimetry: effect of chronic esophageal variceal sclerosis

A technique of endoscopic measurement of gastric mucosal blood flow using laser Doppler velocimetry was described. The technique was validated in the laboratory by performing endoscopic measurement of gastric mucosal blood flow in the dog simultaneously with application of a second probe at open operation, utilizing the same laser Doppler flowmeter. Probe pressure causing minor dimpling (less than 20 gm/cm2) was found to cause insignificant alteration of mucosal blood flow. Criteria were developed to aid separation of artifacts introduced by probe motion. A conversion factor was established for converting the readout of the instrument (Hertz x 10(2] into ml/100g/min by synchronously measuring mucosal blood flow by hydrogen gas clearance technique and laser Doppler velocimetry in the gastric and duodenal mucosa. In patients with portal hypertension gastric mucosal blood flow was determined before and after sclerotherapy, and compared to the gastric mucosal blood flow in subjects without portal hypertension. Gastric mucosal blood flow was elevated in portal hypertensives, but sclerotherapy did not appear to cause changes in blood flow. Endoscopic mucosal blood flow measurement is non-invasive, practical and of potential value in clinical investigation of gastrointestinal pathophysiology.

Percutaneous endoscopic gastrostomy and jejunostomy by a single pass of the endoscope

A modified Gauderer-Ponsky technique of percutaneous endoscopic gastrostomy has been described. The major advantage is elimination of a second insertion of the endoscope, as well as unnecessary traversing of the esophagus by snares and strings. The result achieved is equal to what has been achieved with the original technique, but the single-pass technique is more expeditious and less uncomfortable for the patient. In addition, it can easily be modified to insert both draining gastrostomy and feeding jejunostomy tubes at the same time, using only one pass of the endoscope.

Gastric adaptive changes following experimental gastroplasty

To study the adaptive response of the stomach secondary to partial obstruction imposed by gastroplasty, groups of rabbits with calibrated midgastric constrictions created as a stoma (unreinforced, Group II), as a short channel (Group III), or as a stoma reinforced with polypropylene mesh (Group IV), were compared to controls (Group I). It was found that the unreinforced stoma dilated rapidly while the pouch dilated moderately. In both the channel and reinforced stomas, the pouch dilated markedly. Increased fibrosis was found inside of the polypropylene banding, resulting in a significant incidence of luminal obstruction. The channel dilated in stages, affecting the proximal end first; but obstructive effect remained as long as part of the channel was undilated. We conclude that a narrow stoma is incompatible with a small pouch over time. Since anatomic specifications do not define function, both function (such as emptying) and adaptive changes should be studied in animal models before introduction of any new gastric limiting procedures into clinical practice.

Blood flow in colonic anastomoses. Effect of stapling and suturing

Sutureline blood flow was measured with laser Doppler velocimetry in colonic anastomoses created with the stapler, manual suturing, or a combination. Blood flow was always reduced in the sutureline compared with normal mucosa. Of all the anastomoses studied, tight stapling reduced sutureline blood flow the most, whereas the two-layered manual anastomosis or stapling reinforced with sutures were somewhat less ischemic. Stapling adjusted to bowel wall thickness impaired flow only moderately. It was possible with practice to outperform the stapler by single-layered manual anastomosis using fine sutures. In humans, stapled ileocolostomy had a higher sutureline blood flow than the two-layered manual anastomosis. In view of the existing clinical experience of safe stapling without adjustment for bowel wall thickness, a low sutureline blood flow is probably tolerated to a considerable degree in humans. However, this study clearly shows that tight stapling can reduce sutureline blood flow unduly, whereas superior blood supply can be attained by attention to staple closure height relative to bowel wall thickness.

Palliation of inoperable esophageal carcinoma. Therapeutic endoscopy as an adjunct to combined chemotherapy and radiotherapy

The combined regimen of irradiation and chemotherapy has been successfully used as a preoperative measure to improve the cure rate for squamous cell carcinoma of the esophagus. In the nonresectable patient, we have seen response to this regimen in the form of conversion of the neoplastic stricture into a fibrous one. Dysphagia remained unchanged due to the persistence of a stricture. In this situation, therapeutic endoscopy can be highly effective for relief of dysphagia, as illustrated by a case report, and is proposed as the palliative procedure of choice when the patient has shown response to combined chemotherapy and radiotherapy.

End colostomy and Brooke's ileostomy constructed by surgical stapler

A technique for making an end colostomy and a Brooke's ileostomy using the surgical stapler is described. The resulting stoma is geometrically perfect. No complication or wound infection occurred in a series of 26 stomas observed for up to ten months. The cost of the cartridge may be considered recovered if this technique decreases the operating time by 13 minutes.

The hemodynamic effects of the sclerosant sodium morrhuate in dogs

The hemodynamic effects of systemic administration of 5 per cent sodium morrhuate was evaluated in normal dogs. Dogs in the control group were injected with 2 per cent benzyl alcohol with pH adjusted to 9.5. Animals injected with sodium morrhuate had a significant reduction in cardiac output, arterial blood pressure, portal vein and hepatic artery flows. These changes occurred primarily in the first 30 minutes of observation. In response to the reduction of the hepatic blood flow, there was an increase in portal vein pressure and resistance.

Side-to-side and end-to-side anastomosis in partial gastrectomy and hemicolectomy using the EEA stapler

We have described a new technique for side-to-side gastrojejunostomy as performed in Billroth II gastrectomy and for end-to-side ileocolostomy after right hemicolectomy utilizing the EEA stapler. By introducing the stapler through the area to be resected, we eliminated the need to close insertion enterostomies. This stapling technique also reduces the hazards and complications associated with multiple pursestring sutures normally required for end-to-end anastomosis with the EEA stapler, since, at most, one such suture is used. With minor modifications, the surgical technique can be applied to other operations in the alimentary tract, thus enhancing the utility of the EEA surgical stapler.

Simplified portoazygous disconnection (Tanner's operation) combined with operative sclerotherapy for bleeding varices

A simplified method of portoazygous disconnection employing the linear stapler and operative sclerotherapy was employed in six patients. Endoscopic maintenance sclerotherapy was instituted for five patients in the follow-up period. Combining the operative and endoscopic modalities is attractive, since the deficiencies of each tend to be offset by the other.

Ninety-five percent duodenectomy. An experimental study

Subtotal excision of the duodenum with preservation of the pancreas and bile and pancreatic ducts was achieved in five dogs without complications. Reconstruction was performed by direct anastomosis of the jejunum to the duodenal strip remaining attached to the head of the pancreas. Radiologic, metabolic, and histologic parameters 4 months postoperatively documented the success of this procedure. We suggest that this technique may be used to further investigate the role of the duodenum in digestive physiologic functions and may have clinical applications for benign diseases of the duodenum.

A technique for rapid intubation of the sigmoid and left colon

Repeated endoscopic intubation of the left colon resulted in decompression of the cecum in all four patients with pseudo-obstruction of the colon complicating critical illnesses. The technique involved fiberoptic sigmoidoscopy and placement of a large-bore tube above the sigmoid flexures under visual control. The technique is rapid, safe and readily repeatable and deserves a trial prior to undertaking cecostomy.

The effect of secretin on pancreatic blood flow in the awake and anesthetized dog

The canine pancreatic blood flow was studied after iv secretin (resulting in a plasma level commensurate with the postcibal state), and also after larger iv doses and after duodenal acidification. We found that blood flow was unaffected by "physiological" doses of secretin, or by perfusion of duodenum at a pH as low as 2.0, but increased by bolus doses (0.5 CU/kg and above), and by acidification to pH 1.4. Anesthesia does not affect the blood flow response although the bicarbonate response appeared to be blunted under anesthesia. We conclude that increase in pancreatic blood flow is not a physiological effect of secretin.

Transient bacteremia following endoscopic injection sclerotherapy of esophageal varices

The incidence of transient bacteremia following endoscopic injection sclerotherapy of esophageal varices was evaluated in 18 patients subjected to 40 sessions of injection sclerotherapy. Blood cultures were obtained before sclerotherapy and at five minutes, 30 minutes, and 24 hours after sclerotherapy. The injectors as well as the endoscope were cultured before and after the procedure. Blood cultures were positive in two patients after injection sclerotherapy (Enterobacter cloacae and Staphylococcus species, coagulase-negative, respectively) for an incidence of 5% of transient bacteremia. Pseudomonas aeruginosa was the most frequent bacteria isolated from the injector after sclerotherapy. We conclude that the incidence of transient bacteremia after sclerotherapy is no higher than routine upper-intestinal endoscopy.

Pathogenesis of the "Courvoisier gallbladder"

To investigate the pathophysiological basis of Courvoisier's law, the gallbladder size and pliability were measured in chronic calculous cholecystitis with (7 patients) or without (25 patients) common duct obstruction, in periampullary malignancy (6 patients), and in the normal state (3 patients). The duration and level of jaundice, when present, were correlated to the gallbladder size and ductal pressure as measured at operation. It was found that in vitro the gallbladders were equally pliable in all groups. Therefore, the classical explanation, that stone obstruction of the common duct does not result in dilated gallbladders because of less pliable organs from preexisting fibrosis, does not seem to apply for this series of patients. A markedly higher ductal pressure and a longer history of and deeper jaundice were also found in patients with dilated gallbladders. The data of this study support the alternative explanation that chronically increased ductal pressure is the probable cause of dilated gallbladders seen in malignant obstruction of the common duct.

A case of acute esophageal variceal hemorrhage

All those who deal with patients suffering from this discouraging and lethal disease are constantly searching for the ideal method in which to control active hemorrhage from esophageal varices. Continued nonoperative management in those whose hemorrhage does cease on purely conservative measures results in an unacceptably high mortality, the most common cause of which is recurrent bleeding. Those patients who undergo portoazygos disconnection via the transabdominal or transthoracic route are equally prone to recurrent hemorrhage unless an elective portosystemic shunt is performed. Whether such a shunt is done as an elective or as an emergency procedure, the postoperative mortality and morbidity are high. Although protection against recurrent bleeding can be expected in most, the natural history of liver disease progression (and prognosis therefrom) remains unaltered, if not occasionally aggravated. Resurgence of interest in injection sclerotherapy for immediate control of hemorrhage, with subsequent longterm control of varices by repeated injections at intervals of several months, has received enthusiastic support. Preservation of existing hepatocellular function, the simplicity of the technique, especially with the fibreoptic endoscope, and its likely impact on medical care costs in this disease are attractive benefits. It is not perfect, and prospective randomized controlled trials are required to prove its superiority over other forms of treatment, but it currently appears to be the most viable alternative. We are not alone in fervently hoping that portoazygos disconnection will rarely be required and that portosystemic shunting will become a superfluous procedure, comfortably consigned to the history books.

Injection sclerotherapy for control of acute variceal hemorrhage

Acute variceal hemorrhage can be controlled effectively with injection sclerotherapy using the flexible gastroscope and endoscopic balloon tamponade. The complication rate is low; however, mortality from irreversible liver failure remains high. This technique is suggested as an alternative to standard medical and operative treatment.

Transgastric approach to posterior juxta-esophageal gastric ulcer

Three cases are reported to illustrate the transgastric techniques for approach to posterior wall juxta-esophageal gastric ulcers. The author emphasizes the importance of making the incision or suture line parallel to the esophagus to avoid compromise of esophageal entry. The advantages of this technique include speed, good direct exposure for a mucosal view, and minimal interruption of gastric blood supply in the exploratory phase before planning a definitive procedure. It is particularly suitable for occasions when surgical risks are increased by obesity or critical clinical status, or when the pathology is strictly localized.

Gastrointestinal anastomoses constructed with singly placed staples

Thirty gastrointestinal anastomoses were created in dogs by stapling with singly placed staples, using a commercially available skin and fascial stapler. The exercise served to illustrate the advantages of automation of individual sutures rather than the whole suture line, pointing out a new direction for the future development of gastrointestinal staplers.

Sclerotherapy of esophageal varices

Sclerotherapy of esophageal varices is being reevaluated by many surgeons because of increasing dissatisfaction with shunting procedures. A new technique of sclerotherapy using the flexible fiberoptic endoscope with balloon tamponade of variceal channels is being evaluated. To date, 18 patients have been treated by us with this method. Nine patients with active bleeding had control of their hemorrhage. Two patients experienced three episodes of rebleeding. Of patients not actively bleeding at the time of injection, one patient experienced rebleeding and subsequently died. Four other deaths not related to varices have occurred in this series. All surviving patients underwent repeated sclerotherapy until eradication of varices was achieved. This report demonstrates the feasibility of sclerotherapy of esophageal varices using the flexible fiberoptic endoscope.

Perforation of peptic ulcers related to fiberoptic endoscopy

Three cases of perforation of peptic ulcers related to either fiberoptic endoscopy or esophageal dilation are presented. A correct preoperative diagnosis can be made by recognising the onset of acute abdominal symptoms and signs after an uneventful fiberoptic examination or dilation of stricture in patients with preexisting ulcer symptoms. The complication is especially likely to occur in peptic ulcer disease coexisting with esophageal stricture, possible due to air trapping in the stomach.

A controlled clinical trial of whole gut lavage as a method of bowel preparation for colonic operations

In a prospective randomized clinical trial, whole gut lavage was evaluated against conventional mechanical cleansing for colonic operations. The lavage took less time to perform, was better tolerated by patients, and resulted in more satisfactory preparation as judged by frequency of collapsed intestines. There was no difference in the outcome in the two series as measured by wound infection rate and length of hospitalization. It is concluded that whole gut lavage is as good as conventional mechanical cleansing but surpasses the latter in logistic advantages.

Effects of methylprednisolone on hydrogen ion absorption in the canine stomach

The effect of methylprednisolone (2 mg/kg per day given parenterally for 3 doses, 2 wk or 12 wk) on the permeability of mammalian gastric mucosa to hydrogen ion (H(+)) was examined with denervated fundic pouches in dogs with antrectomies. Transmucosal electric potential difference (PD) and net fluxes of H(+) and Na(+) were determined for luminal [H(+)] from 20 to 160 mM and [Na(+)] from 1 to 140 mM ([H(+)] and [Na(+)] were varied reciprocally). The PD was 50-60 mV lumen negative and was constant over the entire range of Na(+) and H(+) concentration tested. Net H(+) flux varied linearly with [H(+)]. Extrapolation indicated apparent H(+) loss at zero luminal concentration, suggesting a basal HCO(3) (-) secretion. Addition of acetylsalicylic acid (ASA) or taurocholate decreased the PD to 30-40 mV and increased threefold the slope of the relation between net H(+) flux and [H(+)] (k(H)). Calculation of PD-independent permeability constants for H(+) (P(H)) with the Goldman constant field equation indicated that this increase in k(H) could not be attributed solely to the associated decrease in PD. Prednisolone administered for 3 doses had no effect on either the basal mucosal permeability to H(+) or the altered permeability induced by ASA or taurocholate. Chronic administration induced a low rate of basal acid secretion (at 12 wk) but had no effect on either PD or k(H). However, the increase in k(H) and P(H) that developed upon addition of ASA or taurocholate in chronically treated dogs was more than one and a half times that of controls. These data suggest that prolonged treatment with glucocorticoids increases susceptibility of the gastric mucosa to damage by agents that increase permeability to H(+).

Duodenojejunostomy in gastric operations for postbulbar duodenal ulcer

In two cases, two different techniques of duodenojejunostomy were employed as an alternative to an insecure closure of the "difficult duodenal stump." The arrangements are either duodenojejunostomy Roux-en-Y or isoperistaltic jejunal interposition. A single-layered suture line is employed. The ampulla of Vater is visualized during the construction of these anastomoses. In addition to obviating a tenuous stump closure, this technique has the theoretical advantage of providing internal drainage.

Dilation of esophageal strictures. A new technique controlled by fiberoptic endoscopy

Dilation of peptic esophageal strictures visually controlled by means of fiberoptic endoscopy was carried out in 16 patients. The dilation was performed by passing the woven silk bougies alongside the endoscope, so that the process could be observed in detail. The technique affords a better view of the procedure because of a wider visual angle and because the field of vision is not blocked by the bougie, as would be the case with the rigid endoscope. The size of the bougie employed is not limited by the size of the endoscope. All 16 patients, with and without subsequently undergoing Nissen fundoplication, were able to eat a normal diet after therapy.

New procedures. Improved technique for placement of intestinal feeding tube with the fibreoptic endoscope

A feeding tube can be rapidly introduced into the small intestine through a makeshift 'external channel' of the fibreoptic endoscope. To prevent dislodgement of the feeding tube upon withdrawal of the endoscope, the former may be stabilized by means of the biopsy forceps introduced through its regular channel.

Hydrogen ion transport in the rabbit esophagus

The lumen of the rabbit esophagus was perfused in vivo with solutions (one solution per esophagus) containing 0-160 mM HCl by a constant circulation technique for 5 h. During the 1st h, net H+ flux out of the lumen (efflux) was minimal at H+ concentrations of 80 mM or less, but increased linearly with increase in luminal H+ concentrations above 80 mM. After 3 h, the net H+ efflux increased proprtionately to increasing H+ concentrations above a threshold of 20 mM. At the 5th h a linear relationship between net H+ efflux and luminal concentration was seen at all concentrations. Histological damage accompanied increase in H+ efflux and correlated with luminal acid concentrations and duration of exposure. We conclude that the rabbit esophageal mucosa is essentially impermeable to H+ below a threshold concentration of 80 mM for up to 1 h of exposure. When exposure is prolonged, this threshold steadily decreases with time. The occurrence of passive H+ diffusion above threshold concentrations most probably results from an increase in mucosal permeability, possibly an initiating event in the genesis of esophagitis.