Feeding jejunostomy for post-operative nutritional support

Enteral feeding by tube jejunostomy, inserted during definitive surgery, was used in 19 adult patients operated upon in a 24 month period. Jejunostomy feeding was associated with a low rate of minor complications enabling delivery of adequate caloric and protein input shortly after major abdominal operations and up to 9 months later. We feel that the insertion of a regular size jejunostomy tube during surgery is a simple, brief and safe procedure which offers efficient and inexpensive nutritional support, and thus has an important role in the post-operative management of selected patients. It is also easily used in the home setting if needed.

Air encircling the intussusceptum on air enema for intussusception reduction: an indication for surgery?

OBJECTIVES

The prompt identification of children in whom enema reduction of intussusception might fail and surgery is necessary is crucial in order to avoid futile repeat attempts and untoward complications. The purpose of this retrospective review was to determine whether air encircling the intussusceptum in the small bowel during air enema for intussusception reduction could serve as an indication for operation rather than repeat attempts at radiological reduction.

METHODS

Imaging studies of 83 children aged 4 to 40 months with idiopathic intussusception who had air enema for intussusception reduction were reviewed for the presence of air encircling the intussusceptum in the distal small bowel. Findings were correlated with clinical course and surgical findings.

RESULTS

In 12 of 83 patients, air was seen encircling the intussusceptum in the small bowel, and in 11 of these (88%) air enema failed to reduce the intussusception. In 8 of the 11, delayed repeated attempts using air enema failed to reduce intussusception. Clinical signs and their duration did not differ between those children without and those with air encircling the intussusceptum.

CONCLUSION

In the presence of air encircling the intussusceptum in the distal small bowel on air enema, delayed repeated attempts for intussusception reduction are unlikely to succeed, and surgery is indicated.

Ectopic liver tissue within the umbilical cord

A solid mass in the umbilical cord is a very rare finding. A neonate with isolated ectopic liver tissue found in the umbilical cord is reported. This is the first known such reported case.

Liquid enteral diets induce bacterial translocation by increasing cecal flora without changing intestinal motility

The aim of this study was to determine the contribution of intestinal motility and cecal bacterial overgrowth to liquid diet-induced bacterial translocation (BT). Three different commercially available liquid diets were offered to mice for 1 week. BT to the mesenteric lymph nodes (MLN), spleen, and liver were examined as well as cecal bacterial counts and populations, small bowel length and weight, and histopathologic changes in the ileal and jejunal mucosa. In addition, the effect of the various diets on intestinal motility was measured by the transit index of a charcoal mixture introduced into the stomach. The incidence of BT to the mesenteric lymph nodes was significantly and similarly increased (p < .05) in mice fed Vivonex (30%), Ensure (30%), and Osmolite (33%) compared with chow-fed controls (0%). Compared with chow-fed controls, all three liquid diets were associated with the development of cecal bacterial overgrowth (p < .01). There were no significant changes in the transit index for the three liquid diet groups compared with the chow-fed controls. BT to the MLN was induced by all three liquid diets tested, casting some doubts as to their role in preventing BT in clinical use. BT was associated with a statistically significant increase in cecal bacterial count but was not associated with gut motility changes in this model. In fact, no significant changes in intestinal motility were noted in all groups tested.

The alpha-defensins stimulate proteoglycan-dependent catabolism of low-density lipoprotein by vascular cells: a new class of inflammatory apolipoprotein and a possible contributor to atherogenesis

Inflammation may contribute to the pathogenesis of atherosclerosis. On the basis of previous reports that human atherosclerotic lesions contain alpha-defensins, a class of cationic proteins released by activated neutrophils, the study was designed to ask whether defensins modulate the binding and catabolism of low-density lipoprotein (LDL) by human vascular cells. The results of the study demonstrated that defensin stimulated the binding of (125)I-LDL to cultured human umbilical vein endothelial cells, smooth muscle cells, and fibroblasts approximately 5-fold in a dose-dependent and saturable manner. Defensin and LDL formed stable complexes in solution and on cell surfaces. Stimulation of LDL binding by defensin was not inhibited by antibodies against the LDL-receptor (LDL-R), or by recombinant receptor-associated protein, which blocks binding of ligands to the alpha(2)-macroglobulin receptor/LDL-R-related protein and other LDL-R family members. Furthermore, defensin stimulated the binding, endocytosis, and degradation of LDL by fibroblasts lacking LDL-R. Stimulation of LDL degradation by defensin was inhibited approximately 75% by low concentrations of heparin (0.2 units/mL) and was similarly reduced in CHO cells lacking heparan-sulfate-containing proteoglycans. The effect of defensin was substantially increased in cells overexpressing the core protein of the syndecan-1 heparan sulfate proteoglycan. The alpha-defensins released from activated neutrophils may provide a link between inflammation and atherosclerosis by changing the pattern of LDL catabolism from LDL-R to the less efficient LDL-R-independent, proteoglycan-dependent pathway. (Blood. 2000;96:1393-1398)

Pulmonary fibrosarcoma in childhood: fiber-optic bronchoscopic diagnosis and review of the literature

Primary pulmonary fibrosarcoma is a rare malignant tumor in childhood. In the absence of metastases, complete resection is curative. An 8-year-old boy suffered from unresolving pneumonia due to an obstructing lesion in the left main bronchus. Cytology of the bronchoalveolar lavage fluid and histology of bronchial biopsy revealed the diagnosis of pulmonary fibrosarcoma. The tumor did not respond to chemotherapy, and a total lobectomy with sleeve resection was performed with complete removal of the neoplasm. Two years after the operation the child has no evidence of disease.

Thoracoscopic surgery in a general surgical service

Following the great success and wide acceptance of laparoscopic surgery, the mini-invasive approach has been adopted for use in thoracic surgery. Thoracoscopic surgery is gaining acceptability as the procedure of choice for the treatment of recurrent pneumothorax and bullous lung disease, peripheral benign and malignant lesions, diffuse pulmonary infiltrates, mediastinal and pleural lesions, esophageal surgery, and major pulmonary resections for primary lung tumors. We present the 4-year experience of a general surgery service that extended the use of its advanced laparoscopic skills to the performance of thoracoscopic surgery in 80 patients. Using thoracoscopy, we performed biopsy or excision of pulmonary lesions (23 patients), spontaneous pneumothorax (14 patients), thoracic sympathectomy (41 patients), and Heller's esophagomyotomy and pericardiotomy (1 patient each). The results are excellent, and we believe the procedures presented in this series, and similar ones, can be accomplished safely and successfully by well-trained laparoscopic surgeons.

Nitroxide radical attenuates ischaemia/reperfusion injury to the rat small intestine

BACKGROUND

Free radicals are associated with post-ischaemic intestinal injury and contribute to major clinical problems primarily in premature infants. Various antioxidative means and modes of intervention, previously tested, have demonstrated only limited efficacy.

AIMS

To study the protective activity of the stable nitroxide radical 4-OH, 2,2,6,6-tetramethylpiperidine-1-oxyl (TPL) and its respective hydroxylamine (TPL-H) against ischaemia/reperfusion (I/R) injury.

METHODS

An isolated loop of ileum was created in laboratory male Sabra rats and constantly perfused with warmed normal saline. Intestinal injury was elicited through clamping of the superior mesenteric rat artery followed by reperfusion. Either TPL or TPL-H was given intravenously immediately before ischaemia or reperfusion and continuously afterwards. The rate of mucosal to lumen clearance of para-aminohippurate (PAH) was used to evaluate intestinal mucosal injury. Serum and perfusate levels of both TPL and TPL-H were measured using electron paramagnetic resonance spectrometry.

RESULTS

The increase in intestinal permeability induced by I/R was significantly inhibited by both TPL and TPL-H. The nitroxide was effective also when given immediately before reperfusion.

CONCLUSIONS

Through a continuous exchange, TPL and TPL-H act as self-replenishing antioxidants and thus protect from intestinal injury. This demonstrates the potential of the family of nitroxide antioxidants against oxidative stress in general and I/R injury in particular.

Plasma-to-lumen clearance of para-aminohippurate can replace 51Cr EDTA clearance in the evaluation of intestinal mucosal injury

Intestinal mucosal injury of various degrees occurs in many clinical situations and is initially evidenced by altered mucosal permeability. The latter may be assessed in animal models by determination of plasma-to-intestinal lumen clearance of specific molecules, usually chromated 51Cr EDTA. The purpose of this study was to evaluate the usage of para-aminohippurate (PHA) as a substitute for the commonly used radioactive material, i.e., 51Cr-EDTA, in the evaluation of intestinal mucosal injury. An isolated loop of ileum was created in rats and constantly perfused with warmed normal saline. Both renal pedicles were ligated. Either 51Cr-EDTA (18.5 Bq/kg) or PAH (58 mg/kg) was injected i.v. Fifteen-minute intestinal ischemia was produced by clamping the superior mesenteric artery immediately after the end of an equilibration period. The perfusate was collected for 10 min prior to the initiation of intestinal ischemia, during the last 10 min of ischemia, and during the following three 10-min periods of reperfusion. Blood samples were collected at the end of each collection period for the determination of either PAH or 51Cr-EDTA concentrations and the calculation of either PHA or 51Cr-EDTA plasma-to-lumen clearances. PAH and 51Cr-EDTA plasma-to-lumen clearances followed the same pattern in all five assessed periods with no statistical difference between the two. PAH plasma-to-lumen clearance is a feasible, reliable, and inexpensive method for the evaluation of ischemia/reperfusion injury to the intestinal mucosa. It can safely replace the commonly used method in animal models that utilizes radioactive materials such as 51Cr-EDTA.

Laparoscopic Nissen fundoplication in children under 2 years of age

BACKGROUND

Antireflux operations have been recommended for infants and children suffering from complications related to gastroesophageal reflux (GER). In recent years, the laparoscopic approach has been used increasingly for antireflux surgery in adult patients. This is our initial experience with Nissen fundoplication in infants and children under 2 years of age.

PATIENTS

We operated on 11 patients weighing between 3.0 and 10.0 kg. The main indications for surgery were GER-induced aspiration pneumonia and failure to thrive, in spite of intensive conservative treatment. All patients except one had an associated neurological abnormality, including six patients with familial dysautonomia.

RESULTS

All attempted operations were completed successfully laparoscopically, with only a few postoperative complications and acceptable short-term results. The clinical considerations and technical aspects unique to this specific group of patients are discussed.

CONCLUSION

Laparoscopic Nissen fundoplication is feasible, safe, and effective, even in very small babies.

Infantile hemangioendothelioma of the ovary: a monodermal teratoma or a neoplasm of ovarian somatic cells?

Vascular tumors of the female genital tract are uncommon, and only a few cases have been reported in the ovary. We describe herein, an unusual tumor of the ovary: infantile hemangioendothelioma (cellular hemangioma of infancy) in a newborn. The tumor consisted of well-formed blood vessels and proliferating endothelial cells that were arranged in solid cordlike structures. The tumor permeated the ovarian stroma and entrapped normal ovarian follicles. By immunohistochemistry the neoplastic cells expressed factor VIII, CD34, and alpha smooth-muscle actin, and ultrastructurally they had the features of endothelial cells that were focally associated with pericytes. We examined simple sequence repeat (SSR) polymorphic markers in the tumor tissue, as well as in the patient's and parents' blood. The informative SSR markers were found to be identical in the tumor and in the patient's somatic cells. We suggest that the tumor described herein is a congenital infantile hemangioendothelioma arising from ovarian parenchymal cells rather than a teratoma originating from germ cells. A similar morphologic lesion has been described recently in the ovary and interpreted as monodermal teratoma composed of vascular tissue.

[Nissen fundoplication by laparoscopy]

Short term results following laparoscopic Nissen fundoplication were evaluated in 31 patients with symptomatic gastroesophageal reflux. 6 were females and 26 males, and they ranged in age from 5 months to 64 years (mean: 4.9 years in 19 younger than 18 years, and 39.3 years in 12 adults). Most of the adults who complained of pain and heartburn underwent pH monitoring, endoscopy, and manometry as needed. Milk scan was the most useful diagnostic tool for the evaluation of the children, who suffered mainly from gastroesophageal-related pulmonary disease. Indications for laparoscopic operation were identical with those for conventional open Nissen fundoplication. 1 case of dysautonomia died postoperatively; the rate of complications, mostly minor, was 22.5%. 3 patients required conversion to open Nissen fundoplication due to cardiorespiratory instability secondary to pneumothorax in 2, and to esophageal perforation in the third. 5 adults developed temporary dysphagia. 3 children had only partial improvement in their pulmonary disease following the operation, while the other 15 had complete relief. The total time for the laparoscopic operation averaged 245 minutes in adults, and 228 in children. Discharge was usually on the fourth postoperative day in adults (mean: 6.0 days). Regurgitation and heartburn were cured in 10 out of 11 adults (91%). All parents of children were satisfied. Symptomatic outcomes following laparoscopic Nissen fundoplication compare favorably with those of open surgery with respect to mortality, complications, and outcome.

Late-appearing diaphragmatic hernia following resolution of right pleural effusion

A case of late-appearing congenital diaphragmatic hernia in a premature infant with previously normal chest X-ray is reported. Pleural effusion accumulation and resolution preceded herniation of the liver to the right hemithorax and development of respiratory symptoms. Chest X-ray, ultrasound and computed tomography of the chest were useful in establishing the correct diagnosis. Pleural effusion without obvious cause should alert the paediatrician to the possibility of this rare condition.

Cooling strangulated intestine before and following release of an obstruction protects from ischemia/reperfusion injury

OBJECTIVE

To evaluate whether cooling of ischemic intestine before and immediately after the release of the obstruction is more advantageous than is warming in an isolated ileal loop rat model.

DESIGN

Prospective randomized experimental trials.

SETTING

Laboratory.

MATERIALS

Male Sabra rats.

INTERVENTIONS

An isolated loop of ileum was created in rats and constantly perfused with warmed normal saline (37 degrees C). Intestinal ischemia was caused by clamping of the superior mesenteric artery for 15 minutes. Cooling of the isolated ileal loop to 32 degrees C by the application of cold saline was done for the last half of the ischemic period and continued during the first 10 minutes of reperfusion. The intestine was warmed to 37 degrees C for the next 20 minutes of reperfusion.

MAIN OUTCOME MEASURES

The chromium 51-labeled ethylenediaminetetraacetic acid (51Cr-EDTA) plasma-to-lumen clearance rate was used for the evaluation of intestinal mucosal injury. Multiple intestinal samples were harvested at the end of the reperfusion period, and the histological features were evaluated.

RESULTS

The 51Cr-EDTA plasma-to-lumen clearance rates were significantly lower (P < .001) in the rats in which cooling of the ischemic intestine was performed in comparison with the control group, indicating reduced intestinal mucosal injury in all three 10-minute reperfusion periods. Cooling also significantly changed the resultant histological damage to the intestinal mucosa exerted by ischemia (P < .001).

CONCLUSION

Cooling of the ischemic intestine before the release of the obstruction and for a short period during reperfusion provides significant protection from ischemia/ reperfusion injury compared with the traditional method of warming the ischemic intestine.

Gastric outlet obstruction caused by prepyloric mucosal diaphragm mimicking duodenal ulcer: a case report

An 11-year-old child was evaluated for chronic gastric obstruction with intermittent symptoms from the age of 11 months. An upper gastrointestinal series performed at the age of 11 months was interpreted as compatible with severe pyloric stenosis due to a duodenal ulcer, but no surgery was recommended. Several other UGIT series, and at least four endoscopies performed during the following years by experienced gastroenterologists in Israel and in the United States, failed to reveal the true nature of the gastric outlet obstruction. The patient was operated upon shortly after referral to our institute. Upon celiotomy, a congenital antral web was found, the excision of which resulted in long-term relief of all symptoms. The differential diagnoses of childhood gastric outlet obstruction and the possible pitfalls in the diagnostic workup are discussed.

Laparoscopic-modified Nissen fundoplication in children with familial dysautonomia

Children with familial dysautonomia (FD) often require an antireflux operation and gastrostomy to prevent the detrimental effects of aspirated gastric juice on the lungs and to facilitate liquid feeding. The aim of this study was to examine whether a laparoscopic procedure in such patients is as safe and effective as the traditional open technique. The data for all pediatric patients who underwent a laparoscopic antireflux procedure for familial dysautonomia were reviewed and compared with those the last pediatric patients with FD who were operated upon using the open technique, before the introduction of the laparoscopic procedure. Of the 61 children who underwent an antireflux procedure for FD (1978-1996), 13 were operated on laparoscopically. The authors found that the postoperative course of these patients was less complicated than that of patients who had the traditional laparotomy procedure. There was no need for mechanical ventilation during the postoperative course, and there were no respiratory complications. The mean hospitalization period was significantly shorter (7.9 days v 13.2 days). There were no complications attributable to laparoscopy, and the antireflux procedure has been effective in all patients (short-term follow-up). The authors conclude that laparoscopic procedures that include a modified Nissen fundoplication, gastrostomy, and appendectomy are feasible and as safe as conventional surgery for the treatment of FD in children. It appears that this approach has fewer complications than laparotomy, might reduce the need for postoperative mechanical ventilation, and is associated with a shorter postoperative stay.

[Laparoscopic surgery in children and adolescents]

Laparoscopic surgery is a rapidly developing field in general surgery. The advantages of laparoscopic procedures are short postoperative courses, fewer wound-related complications, possible reduction in rate of late postoperative adhesions and better cosmetic results. Laparoscopic procedures are indicated in well-defined clinical settings, after enough experience has been acquired and technical problems solved. Children and adolescents may also benefit from laparoscopic procedures. The technique is suitable for cholecystectomies, appendectomies in selected cases, splenectomies, anti-reflux procedures, bowel resections, and diagnostic procedures, among others. In the past 3 years we have performed 65 laparoscopic procedures in patients younger than 17 years, including 10 cholecystectomies, 31 appendectomies and 7 Nissen fundoplications.

Nitric oxide-containing nerves in bowel segments of patients with Hirschsprung's disease

To assess the role of nerves that synthesize nitric oxide (NO) in Hirschsprung's Disease (HD), the authors studied the distribution of the enzyme NADPH diaphorase (NADPHd) in normal and diseased bowel segments. In the proximal (ganglionic) segment of the colon, NADPHd-positive neurons were present in both myenteric and submucosal plexuses. In the distal involved colonic segments from HD patients, the typical pattern of the neuronal network was completely missing in the regions of the two plexuses; instead, only disorganized NADPHd-positive nerve fibers were present and NADPHd-reactive neurons were absent. Mucosal NO synthase activity was 2.76 +/- 0.38 nmol/g/min in the proximal segment and only 0.83 +/- 0.49 nmol/g/min in the distal segment (P < .05, N = 3).

Postischemic intestinal motility in rat is inversely correlated to length of ischemia. An in vivo animal model

An inverse correlation between postischemic gastrointestinal motility and the length of intestinal ischemia was found in an animal model. Intestinal ischemia was caused without concurrent laparotomy and for a predetermined time period (ischemia time) by pulling on an external nylon thread that was threaded through a double-lumen catheter. This catheter was passed into the abdominal cavity to encircle the superior mesenteric artery. Gastrointestinal motility was determined by the introduction of a color-marked meal into the animal's stomach and the measurement of the proportionate length of the small bowel filled with it (transit index). This simple and reliable animal model can also be used for the evaluation of techniques and pharmacological manipulations aimed at modulation of the effects of intestinal ischemia on intestinal motility and its consequences.

Antley-Bixler syndrome and esophageal atresia in a patient with trisomy 21

The Antley-Bixler syndrome (ABS) is characterized by craniofacial, skeletal and urogenital anomalies. While most patients with ABS die of severe respiratory complications in their first months, long-term survivors have been reported. We report an infant girl, born to a consanguineous couple, with craniofacial and skeletal anomalies, consistent with ABS, in addition to atresia of the esophagus and trisomy 21.

A pitfall in the technique of jejunal tube insertion, resulting in jejunal perforation

Enteral feeding by a jejunostomy tube is a reliable and cost-effective method for both long- and short-term nutritional support in selected patients, although a high complication rate has been reported in some series. The authors report on jejunal perforation in an infant, caused by a kinked jejunostomy tube, and emphasize this possible pitfall as a warning to others.

Epidural anesthesia accelerates the recovery of postischemic bowel motility in the rat

BACKGROUND

Intestinal ischemia is associated with derangement of gastrointestinal motility. Uncontrolled clinical observations that bupivacaine injected into the epidural space causes faster recovery of bowel motility after various abdominal operations led us to assess the hypothesis that epidural anesthesia can hasten the recovery of gastrointestinal motility in the immediate postischemic period.

METHODS

Gut motility studies were performed in rats in which epidural anesthesia and intestinal ischemia could be initiated without the need to provoke surgical trauma. Epidural lidocaine was compared to epidural saline in their effect on intestinal motility after a 30-min period of bowel ischemia.

RESULTS

Total ischemia to the small bowel resulted in pronounced postischemic adynamic ileus as evidenced by only 0.7% of the total length of the small bowel filled with a marker meal at the end of the study period (transit index) compared with 84.4% in the control group. Lidocaine epidural anesthesia caused significantly more rapid resolution of the adynamic ileus (60.3% of the bowel filled with the marker meal vs. 30.9% in the controls in which saline was injected).

CONCLUSIONS

Epidural lidocaine compared to epidural saline hastens the recovery of gastrointestinal motility in rats after a 30-min period of bowel ischemia. This effect may be elicited by attenuation of sympathetic efferent inhibitory pathways or by vasodilatation caused by the sympathetic block. These results suggest that lidocaine epidural block not only alleviates pain in situations of ischemic injury to the bowel but may also hasten the recovery from postischemic paralytic ileus.

The time sequence of injury and recovery following transient reversible intestinal ischemia

Intestinal mucosal damage and regeneration were examined in rats following transient ischemia produced by the occlusion of the superior mesenteric artery for 30 min. Animal groups were assigned for harvesting of small bowel specimens at 10, 17, and 30 min and 1, 2, 3, 4, 6, 12, and 24 hr post-relief of ischemia. Severe damage to the villi was evident already at 10 min postischemia. Thereafter a very rapid restitutional process was observed with restoration of villi epithelium in 47.6% of the examined animals at 60 min, 75% at 4 hr, and 100% at 12 hr. This rapid sequence of events should be taken into consideration when designing experimental ischemic bowel animal models and possible therapeutic modalities.

A simple and rapid method for staining the enteric ganglia: application for Hirschsprung's disease

A simple and reliable method is described for staining the nerve plexuses of the human gastrointestinal tract in whole-mounts. The staining does not require fixation and consists of a single step of 6 to 10 minutes incubation in a solution of the fluorescent dye 4-(4-diethylaminostyryl)-methylpyridinium iodide. Aganglionic bowel specimens from 6 patients with Hirschsprung's disease were stained by this method and displayed the absence of ganglion cells and an abundance of nerve fibers in the myenteric and submucosal plexuses. This staining may be suitable for the diagnosis of Hirschsprung's disease.

[Spontaneous splenic rupture associated with facial erysipelas]

Spontaneous rupture of the spleen is rare Although over 100 cases have been reported, only a few were of true spontaneous rupture. Most cases were associated with diseases which directly involved the spleen. We report a 53-year-old woman with facial erysipelas and true spontaneous rupture of the spleen.

Nissen fundoplication in the treatment of children with familial dysautonomia

Thirty-four children with familial dysautonomia (FD) underwent Nissen fundoplication and gastrostomy. The indications for operation were persistent cyclic vomiting that resulted in repeated aspiration pneumonia (94% of the patients), chronic dehydration (82%), failure to thrive (97%), and frequent hospitalizations (76%). There was no operative or early postoperative mortality. Long-term follow-up for up to 12 years was available. Eight patients died during this period from 7 months to 7.5 years postoperatively. In 5 patients (15% of the operated patients), the fundoplication ceased to function 16 months to 5 years postoperatively, which was attributed mainly to repeated severe dysautonomic crises with vigorous retching. Vomiting ceased in 85% of the symptomatic patients; pulmonary deterioration was halted, and the frequency of aspiration pneumonia was reduced in 68%; nutritional improvement was seen in 44%; the hydration status improved in 88%; and the frequency of hospital admissions decreased in 74%. These long-term findings resulted in a significant improvement in the quality of life for the majority of the patients. The absence of operative mortality and the low postoperative morbidity, together with the long-term beneficial results of this surgical procedure, should encourage early surgical intervention in selected FD patients.

Eicosanoids in hypoxic insult to neonatal rabbit bowel

Eicosanoids, derivatives of arachidonic acid, play a role in several inflammatory diseases of the bowel. To determine whether prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and leukotriene C4D4E4 (LTC4D4E4), have a role in hypoxic insult to the intestine, we examined the levels of these mediators in a hypoxic neonatal rabbit model. One group of animals underwent hypoxic insult postnatally, the second group did not undergo hypoxia and served as a control. The levels of PGE2, LTB4, and LTC4D4E4 were determined by radioimmunoassay. PGE2 in the hypoxic group was 1,779 +/- 142 pg/mg protein (mean +/- SD) as opposed to 2,380 +/- 197 pg/mg protein in the control group (p less than 0.02). LTB4 level was 5,446 +/- 3,492 pg/mg protein in the hypoxic rabbits and 3,362 +/- 2,570 pg/mg protein in the control group (p less than 0.03). There was no statistically significant difference in the level of LTC4D4E4 between the two groups. Our study shows that hypoxia shifts the arachidonic acid metabolism toward enhanced lipoxygenase activity with a resultant increase in LTB4 levels and a concomitant decrease in cyclooxygenase activity with reduced PGE2 levels in the bowel. The shift in the balance between these eicosanoids may play a role in the pathogenesis of ischemic-hypoxic bowel diseases by enhancing the inflammatory response in the intestine, and simultaneously, diminishing cytoprotection.

Acquired tracheoesophageal fistula in infancy and childhood

Acquired tracheoesophageal fistula (TEF) is a rare entity in the pediatric age group. We report two pediatric patients with acquired TEF caused by shells of pistachio nuts. In both patients the primary operation did not resolve the problem and a second intervention for recurrent fistula was needed. The special nature of acquired TEF, particularly the one described herein, requires delayed surgical intervention and meticulous separation of the respiratory and alimentary tracts by an intercostal muscle flap.

Mechanistic aspects of 1-methyl-4-phenyl pyridinium iodide toxicity in Escherichia coli: the role of oxygen and hydrogen peroxide

1-Methyl-4-phenyl pyridinium iodide (MPP+) and paraquat (PQ+2) are two structurally analogous and highly toxic pyridinium compounds. The mechanism of PQ+2 toxicity is best understood in the bacterial model system. While numerous studies in a variety of systems have indicated the causative role of free radicals and other oxygen-derived active species in PQ+2 toxicity, this question is yet unresolved in the case of MPP+. In this study we have used the Escherichia coli model and demonstrated that MPP+ is toxic to bacterial cells in dose- and time-dependent modes. Additionally, it is shown that only in the presence of molecular oxygen did bacterial inactivation occur. This requirement for oxygen can be circumvented by adventitious H2O2. The protective effects of the chemical scavenger--mannitol--and of histidine are presented. These results are in complete accord with a free radical mechanism for MPP+ toxicity.

Salicylate as an in vivo free radical trap: studies on ischemic insult to the rat intestine

Ischemia of rat intestine was induced in vivo by occlusion of the superior mesenteric artery (SMA) for 15 min. Sodium salicylate, 100 mg/kg, given IP, 30 min prior to the ischemic event served as a specific trap for hydroxyl radicals. Portions of the bowel were sequentially isolated and removed--2 min prior to ischemia, 2 min prior to declamping of the SMA, and 10 min following reperfusion. The bowel segments were homogenized in 3% TCA. The homogenate was centrifuged and filtrated through a 0.22 mu filter. The hydroxylation products of salicylate, dihydroxybenzoic acid (DHBA) derivatives, were isolated, identified, and quantified by HPLC coupled with electrochemical detection (ECD). The level of 2,5-DHBA (M +/- SE, ng/g tissue) in the preischemic bowel (N = 21) was 241.8 +/- 10.0. In the ischemic specimen the level of 2,5-DHBA increased significantly to 313.3 +/- 15.5 (p = 0.0129), and remained unchanged in the reperfusion period (322.8 +/- 15.5). The histological examination correlated well with these levels: mild villi damage in the ischemic period with no further exacerbation during the reperfusion period. This study in an in vivo animal model of intestinal ischemia-reperfusion provides direct evidence for the involvement of free radicals during the ischemic insult.

Direct evidence for the involvement of free radicals in ischemic insult to the intestine

Ischemia of rat intestine was induced in vivo by occlusion of the superior mesenteric artery (SMA) for 15 min. Sodium salicylate, 100 mg/kg, given IP, 30 min prior to the ischemic event served as a specific trap for hydroxyl radicals and provided direct evidence for the involvement of free radicals during the ischemic insult. Portions of the bowel were sequentially isolated and removed. The hydroxylation products, dihydroxybenzoic acid (DHBA) derivatives were isolated, identified and quantified by HPLC coupled with electrochemical detection (ECD). The level of 2,5-DHBA (Mean +/- SE, ng/g tissue) in the preischemic bowel (N = 21) was 241.8 +/- 10.0. It rose significantly to 313.3 +/- 15.5 in the ischemic specimen (p = 0.0129) and remained unchanged in the reperfusion period (322.8 +/- 15.5). The histological examination correlated well with these levels: mild villi damage in the ischemic period with no further damage in the reperfusion period.

Long-term evaluation of a new selectively biodegradable vascular graft coated with polyethylene oxide-polylactic acid for right ventricular conduit. An experimental study

Low-porosity woven Dacron grafts have been used extensively as an extracardiac conduit in the surgical treatment of congenital and acquired heart diseases involving total heparinization. Caution is still warranted in their use, however, because of long-term complications, including calcification and development of obstructive fibrous peel. In contrast, high-porosity grafts offer much better tissue anchorage and healing but cannot be used under heparinization. We have developed a compound vascular prosthesis in which a knitted Dacron graft is coated with a polymeric biodegradable sealant. Polyethylene oxide-polylactic acid-segmented copolymers comprised the degradable component of the graft. In vitro studies showed that the coated prosthesis exhibited a highly flexible elastomer-like mechanical response. The prostheses were completely watertight, and significant degradation started after 1 week, with absorption completed after 3 weeks. Seven woven and six knitted polyethylene oxide-polylactic acid-coated Dacron grafts used as extracordiac conduits (16 mm), connecting the right ventricle and the pulmonary artery were implanted in dogs. The dogs were killed after 12 to 18 months, and the results are reported. Scanning electron microscopy examination showed peel detachment and nonhomogenous intimal surface with fenestrations in the woven graft group, but complete healing and incorporation of the pseudointima with homogenous, thin lining of the luminal surface in the polyethylene oxide-polylactic acid-coated group. Histologic studies indicated much superior healing and anchorage of the periprosthetic tissue and the pseudointima in the polyethylene oxide-polylactic acid-coated grafts. The biodegradable polymer was fully degraded and exhibited a complete incorporation of the compound vascular prosthesis. This study indicates the superior healing properties of these selectively biodegradable grafts, which might increase long-term patency and decrease complications of right ventricular conduits.

[Congenital diaphragmatic hernia presenting after the neonatal period]

Congenital diaphragmatic hernia (Bochdalek) is a congenital malformation usually presenting early after birth with a mortality of 50-70%. It is rarely diagnosed after the neonatal period, when the prognosis is considered favorable. We operated on 11 children past the neonatal period, ranging from 6 months to 5.5 years of age. 9 had presented with respiratory symptoms and were operated on semi-electively with excellent results. 2, operated on for strangulation of bowel incarcerated in the hernia, eventually died (aged 7 months and 1 year, respectively). Early diagnosis is important, as early surgery is recommended, even in those without symptoms.

[Physiological responses to heat and effort and complaints of hyperperspiration]

The sensation of hyperperspiration is a common complaint in hot, humid climates. 54 men and 20 women, 18-47 years old, who had this complaint and 27 male control subjects were examined at rest and after 1 hour of mild exercise (40W) under conditions of heat stress (37 degrees C, 50% relative humidity). During exposure to heat rectal and skin temperatures and heart rate were measured every 15 min. Sweat rate was calculated for the entire period of exposure and sweat gland density was measured at 0, 60 and 120 min. Only insignificant deviations from baseline values were noted at rest. During exercise the sweat rate of the men with the complaint was within normal limits and similar to that of the control men (285 +/- 75 ml/m2 vs 272 +/- 48). Matching for age and V02 max revealed no significant differences in physiological responses of men with and those without the complaint. Women with the complaint lost 25-30% less fluid (226 +/- 67 ml/m2) and their concentrations of active sweat glands were lower than in either of the male groups. 2 men and 1 woman with the complaint and 1 control lost 400-425 ml/m2 during exercise, the upper limit of normal. Only 1 subject showed hyperperspiration (855 ml/m2) during the test. All physiological parameters examined in these 5 subjects were within normal limits. It is concluded that the complaint of hyperperspiration in our self-selected group is basically a subjective feeling and has no pathological basis. None of the subjects was heat intolerant.

Peritonitis and empyema following the use of dextran in tubal operations

Two patients developed severe bacterial sepsis with peritonitis and pleural empyema following tubal surgery. Intraperitoneal low-molecular dextran was used in both patients and hydrocortisone was administered perioperatively. The use of dextran in tubal surgery probably increases the risk of severe postoperative infection and should be avoided in susceptible patients. Prophylactic antibiotics may be indicated when dextran is administered.

Gallbladder distention in premature neonates receiving parenteral nutrition

Contraction of the gallbladder is mediated through the release of cholecystokinin from duodenal cells secondary to enteral feedings. Premature infants are often nourished by parenteral hyperalimentation leading to prolonged inactivation of the gallbladder. Such inactivation probably accounts for the increased incidence of gallbladder distention observed in premature neonates. Two cases of premature infants are described in whom distention of the gallbladder occurred during parenteral hyperalimentation. The distention resolved spontaneously secondary to the introduction of enteral feedings. A trial period of oral or tube feeding is recommended in such cases prior to any attempt to release the distention by a surgical intervention.

Ring 18 chromosome with mental retardation, hemidysmorphism, and mitochondrial encephalomyopathy

A 2 1/2-year-old female is reported with ring 18 chromosome syndrome. The chromosomal abnormality was found in all examined leukocytes and cultured skin fibroblasts. Besides the usual clinical characteristics of this syndrome, two additional features are described that have not been reported previously: right hemidysmorphism, including hypertrophy of the tongue and lower extremity; coloboma of the lower right side of the gums; atretic external right ear canal; and hypotonia with mitochondrial encephalomyopathy associated with excessive ketonemia during normal food intake and a large increase after overnight fast.

Multiple gastrointestinal atresias with intraluminal calcifications

A case is reported of multiple atresia of the entire gastrointestinal tract, extending from the stomach to the distal colon. The defect is rare and no survivors have been reported.

Gastrointestinal perforations in the neonatal period

Forty-eight neonates were treated for gastrointestinal perforation during a 9-year period. In 30, perforation occurred within the first week of life. Thirty-six were preterm infants and many had a history of obstetric and postnatal complications. Perforation resulted from necrotizing enterocolitis in 26 patients, whereas in 14 neonates spontaneous perforation occurred in an apparently normal bowel, with no evident cause (idiopathic perforation). In 6 patients perforation was associated with meconium ileus. Primary closure was carried out for perforations of the duodenum and stomach. Intestinal perforations were usually treated by resection and enterostomies. The overall mortality rate in this series was 46%. The highest mortality rate was associated with necrotizing enterocolitis (62%). The mortality rate was only 14% in patients with idiopathic perforation. Despite improvement in the prognosis of neonatal gastrointestinal perforations in recent years, it is still discouraging, reflecting the difficulty in preventing and treating necrotizing enterocolitis.

Idiopathic gastrointestinal perforation in the neonate

Spontaneous localized perforation of the gastrointestinal tract, unrelated to mechanical intestinal obstruction and with no evidence of necrotizing entrocolitis (NEC), occurred in 20 neonates. Three perforations were located in the stomach, 11 in the small intestine, and six in the colon. Maternal obstetric complications as well as prematurity and postnatal distress were common in these patients. The overall survival rate was 80%. There was no late gastrointestinal symptoms in the survivors. Whether idiopathic perforation of the gastrointestinal tract results from a localized form of NEC or from a distinct lesion of unknown etiology has not yet been ascertained. Some ideas concerning the etiology of this entity, as well as some diagnostic aspects are discussed.

Localized pseudomembranous colitis simulating carcinoma of the cecum

A 76-yr-old woman complained of right lower quadrant abdominal pain, nausea, and fever. There was no history of antibiotic therapy or preceding diarrhea. At laparotomy, a cecal lesion simulating a tumor was found with an otherwise normal colon. Right hemicolectomy was performed. Pathological examination showed pseudomembranous colitis confined to the cecum. It is suggested that pseudomembranous colitis unrelated to prior exposure to antimicrobial agents can occur without diarrhea, and may be a localized process mimicking colonic carcinoma.

Serum copper level in gynecologic malignancies

Serum copper level was determined before operation in 179 patients with various histologically proved gynecologic tumors: malignant, benign, or metastases to the ovary. Serum copper level was significantly higher (p less than 0.01) in all groups of patients with cancer and in the benign group when compared with control subjects. Serum copper level correlated well with stage of cancer disease (r = 0.70 to 0.79) except for ovarian carcinoma, in which serum copper level was already significantly elevated in Stages I and II. The sensitivity of serum copper level greater than 150 micrograms/dl in detecting malignancy was 87% to 100% in late cancer stages in all malignancies. Our data imply that the addition of serum copper level determination to other screening tests could increase their sensitivity.