Guidelines for the management of postoperative obstructive symptoms in children with Hirschsprung disease.

Although most children with Hirschsprung disease ultimately do well, many experience a variety of ongoing problems after pull-through surgery. The most common include obstructive symptoms, soiling, enterocolitis and failure to thrive. The purpose of this guideline is to present a rational approach to the management of postoperative obstructive symptoms in children with Hirschsprung disease. The American Pediatric Surgical Association Board of Governors established a Hirschsprung Disease Interest Group. Group discussions, literature review and expert consensus were then used to summarize the current state of knowledge regarding causes, methods of diagnosis, and treatment approaches to children with obstructive symptoms following pull-through for Hirschsprung disease. Causes of obstructive symptoms post-pull-through include mechanical obstruction; persistent or acquired aganglionosis, hypoganglionosis, or transition zone pull-through; internal sphincter achalasia; disordered motility in the proximal intestine that contains ganglion cells; or functional megacolon caused by stool-holding behavior. An algorithm for the diagnosis and management of obstructive symptoms after a pull-through for Hirschsprung disease is presented. A stepwise, logical approach to the diagnosis and management of patients experiencing obstructive symptoms following pull-through for Hirschsprung disease can facilitate treatment. Level of evidence V.

Non-operative treatment versus percutaneous drainage of pancreatic pseudocysts in children.

PURPOSE: The objective of this study was to characterize the clinical course and outcomes of children with pancreatic pseudocysts that were initially treated non-operatively or with percutaneous drainage. METHODS: A retrospective review of children with pancreatic pseudocysts over a 12-year period was completed. Categorical variables were compared using Fischer's exact method and the Student's t test was used to compare continuous variables. Analysis was done using logistic and linear regression models. RESULTS: Thirty-six children met the criteria for pancreatic pseudocyst and 33 children were treated either non-operatively or with percutaneous drainage. Of the 22 children managed non-operatively, 17 required no additional intervention (77 %) and five required surgery. Operative procedures were: Frey procedure (3), distal pancreatectomy (1), and cystgastrostomy (1). Eight of the 11 children treated with initial percutaneous drainage required no additional treatment (72 %). The other three children underwent distal pancreatectomy. Success of non-operative management or percutaneous drainage was not dependent on size or complexity of the pseudocyst Logistic regression did not identify any patient demographic (gender, age, and weight), etiologic (trauma, non-traumatic pancreatitis) or pseudocyst characteristic (size, septations) that predicted failure of non-operative therapy. CONCLUSIONS: In children, pancreatic pseudocysts can frequently be managed without surgery regardless of size or complexity of the pseudocyst. When an intervention is needed, percutaneous drainage can be performed successfully, avoiding the need for major surgical intervention in the majority of patients.

A population-based comparison of joint survival of hemiarthroplasty versus total shoulder arthroplasty in osteoarthritis and rheumatoid arthritis.

AIMS: Few studies have compared survivorship of total shoulder arthroplasty (TSA) with hemiarthroplasty (HA). This observational study compared survivorship of TSA with HA while controlling for important covariables and accounting for death as a competing risk. PATIENTS AND METHODS: All patients who underwent shoulder arthroplasty in Ontario, Canada between April 2002 and March 2012 were identified using population-based health administrative data. We used the Fine-Gray sub-distribution hazard model to measure the association of arthroplasty type with time to revision surgery (accounting for death as a competing risk) controlling for age, gender, Charlson Comorbidity Index, income quintile, diagnosis, and surgeon factors. RESULTS: During the study period, 5777 patients underwent shoulder arthroplasty (4079 TSA, 70.6%; 1698 HA, 29.4%), 321 (5.6%) underwent revision, and 1090 (18.9%) died. TSA patients were older (TSA mean age 68.4 years (sd 10.2) vs HA mean age 66.5 years (sd 12.7); p = 0.001). The proportion of female patients was slightly lower in the TSA group (58.0% vs 58.4%). The adjusted association between surgery type and time to shoulder revision interacted significantly with patient age. Compared with TSA patients, revision was more common in the HA group (adjusted-health ratio (HR) 1.214, 95% confidence interval (CI) 0.96 to 1.53) but this did not reach statistical significance. CONCLUSION: Although there was a trend towards higher revision risk in patients undergoing HA, we found no statistically significant difference in survivorship between patients undergoing TSA or HA. Cite this article: Bone Joint J 2019;101-B:454-460.

Lessons learned from laparoscopic treatment of gastric and gastroesophageal junction stromal cell tumors.

BACKGROUND: Stromal cell tumors of the gastric and gastroesophageal junction are rare neoplasms that traditionally have been resected for negative margins using an open approach. This study aimed to evaluate the efficacy laparoscopic resection of gastric and gastroesophageal stromal cell tumors and the lessons learned from experience with this method. METHODS: This retrospective review evaluated all patients who underwent laparoscopic resection of gastric or esophageal stromal cell tumors at a tertiary referral center between December 2002 and March 2005. Medical records were reviewed with regard to patient demographics, preoperative evaluation, operative approach, tumor location and pathology, length of operation, complications, and length of hospital stay. RESULTS: A total of 12 consecutive patients with a mean age of 55 +/- 5.9 years were treated. Preoperative endoscopic ultrasound (EUS) was performed for 11 of 12 patients with a diagnostic accuracy of 100%, whereas EUS-guided fine-needle aspiration was performed for 10 of 12 patients with a diagnostic accuracy of 50%. Four patients with symptomatic gastroesophageal junction leiomyomas were treated with enucleation and Nissen fundoplication. Eight patients were treated with laparoscopic wedge resection of gastric lesions. Complete R0 resection was achieved for all the patients undergoing laparoscopic resection. Intraoperative endoscopy was performed for four patients and resulted in shorter operative times. The average operative time for this entire series was 169 +/- 17 min: 199 +/- 24 min for the first six cases and 138 +/- 19 min for the last six cases. The median hospital length of stay was 2 days. One patient with esophageal leiomyoma had persistent dysphagia at the 12-month follow-up assessment. There were no other complications and no deaths in this series of patients. CONCLUSIONS: Laparoscopic resection of gastric and gastroesophageal junction stromal cell tumors may be performed safely with low patient morbidity. This approach can achieve adequate surgical margins and lead to short hospital stays. Improvements in the technique have led to shorter operative times.

Wound oxygen levels during hyperbaric oxygen treatment in healing wounds.

Hyperbaric oxygen (HBO2) increases wound oxygen delivery, but few data quantify wound oxygen levels over the course of healing. We characterized these changes during and after HBO2 treatment in a rat wound model. The treatment group (n=7) received 2.0 ATA HBO2, 90 minutes BID for 15 days. Control rats (n=5) were only exposed to HBO2 during measurement. On days 5, 10, and 15, wound pO2 was measured before, during, and for an hour after HBO2 treatment. Both the peak pO2 and the pO2 one hour after HBO2 treatment were significantly greater than baseline on all days in both the treatment (p < .01) and control group (p < .05). The peak pO2 during HBO2 exposure and one hour after decreased significantly in the treatment group on day 15 compared to day 5 (p <.01, p <.05 respectively). No significant differences were found in pO2 values between days within the control group. These results demonstrate that both the peak wound oxygen levels and duration of elevation change significantly throughout the course of HBO2 treatment.

Effect of hyperoxia on vascular endothelial growth factor levels in a wound model.

HYPOTHESIS: Hyperbaric oxygen (HBO) therapy increases vascular endothelial growth factor (VEGF) levels in wounds. DESIGN: Wounds were monitored for oxygen delivery during HBO treatment, and wound fluids were analyzed for VEGF and lactate on days 2, 5, and 10 following wounding. SETTING: Experimental animal model. INTERVENTIONS: Rats were randomized to HBO therapy and control groups. The HBO therapy was administered for 90 minutes, twice daily with 100% oxygen at 2.1 atmospheres absolute. Treatment was administered for 7 days following wounding. MAIN OUTCOME MEASURES: Vascular endothelial growth factor, PO(2), and lactate levels in wound fluid were measured on days 2, 5, and 10. RESULTS: Wound oxygen rises with HBO from nearly 0 mm Hg to as high as 600 mm Hg. The peak level occurs at the end of the 90-minute treatment, and hyperoxia of lessening degree persists for approximately 1 hour. The VEGF levels significantly increase with HBO by approximately 40% 5 days following wounding and decrease to control levels 3 days after exposures are stopped. Wound lactate levels remain unchanged with HBO treatment (range, 2.0-10.5 mmol/L). CONCLUSIONS: Increased VEGF production seems to explain in part the angiogenic action of HBO. This supports other data that hypoxia is not necessarily a requirement for wound VEGF production.

Laparoscopy for appendicitis and cholelithiasis during pregnancy: a new standard of care.

BACKGROUND: Subsequent to a report from the authors' institution, the laparoscopic management of symptomatic cholelithiasis and appendicitis during pregnancy has become the standard of care at LDS Hospital using institutional guidelines. For comparison with previous outcomes described by the authors, 59 additional laparoscopic cases are reported. METHODS: Medical records of all pregnant patients at LDS Hospital who underwent open or laparoscopic cholecystectomy or appendectomy between 1998 and 2002 were reviewed. The outcomes were compared with the authors' previous data. RESULTS: The laparoscopic management of symptomatic cholelithiasis and appendicitis during pregnancy increased from 54% to 97%. No significant differences in preterm delivery rates, birth weights, or 5-min Apgar scores were found between the two periods. No birth defects or uterine injuries occurred. CONCLUSIONS: With the use of the authors' guidelines, laparoscopy has become the standard of care for managing symptomatic cholelithiasis and appendicitis during pregnancy at LDS Hospital without significant increase in morbidity or mortality.

Transabdominal oxygenation using perfluorocarbons.

PURPOSE: Evaluation of the intraabdominal (intraperitoneal and intraluminal) administration of oxygen-saturated perfluorocarbon on both portal and arterial blood oxygenation. METHODS: Eight male rabbits were divided into the test (n = 5) and control (n = 3) groups. Each underwent intrajejunal, intraperitoneal, and intravascular (artery, portal vein) catheter placements along with ligation of the duodenum and the terminal ileum under general anesthesia. The test group received oxygen-saturated perfluorotripropylamine (FTPA), and the control group received oxygen desaturated FTPA. The oxygen delivery was assessed by serial blood gas measurements before and after the administration of FTPA. RESULTS: The administration of oxygen-saturated FTPA significantly increased the partial pressure of oxygen within both the arterial and the portal venous blood (PaO2, PpVO2) without significant changes in PCO2 values. Oxygen desaturated FTPA failed to show any effects on blood gas values. Compared with oxygen desaturated FTPA, oxygen-saturated FTPA increased PaO2, PpVO2, and oxygen saturation (artery, portal vein) significantly at some, but not all of the time-points measured. CONCLUSIONS: The intraabdominal administration of saturated FTPA improved both the portal venous and the arterial oxygenation. This new mode of oxygenation may be helpful as an adjunct to conventional oxygen delivery systems.

Cord blood erythropoietin, pH, PaO2 and haematocrit following caesarean section before labour.

We have investigated the relationship between erythropoietin (Epo) and pH, PaO2 and haematocrit in 100 cord blood samples obtained at Caesarean section prior to labour. Of 82 term (> 37 weeks) infants, 64 were appropriately grown (10th-90th centiles), and their mean cord serum Epo and cord blood Epo was 23 +/- 8 mU/ml (mean +/- SD). Strong inverse correlations were found between cord serum Epo and cord blood pH (r = -0.74; p < 0.0001), and between cord serum Epo and cord blood PaO2 (r = -0.55; p < 0.0001), but not between cord serum Epo and cord haematocrit (r = 0.02; p < 0.9). For the 18 preterm babies (gestation 32.4 +/- 4.1 weeks, birth weight 1,820 +/- 476 g), the Epo level was 36 +/- 8 mU/ml, which was not significantly greater than for the term babies. Strong inverse correlations were again found between Epo and pH (r = -0.87; p < 0.0001) and Epo and PaO2 (r = -0.69; p < 0.002). Babies from complicated pregnancies (intra-uterine growth retardation, pre-eclampsia, antepartum haemorrhage, diabetes mellitus and fetal distress) tended to have higher Epo levels. Thirteen babies had Epo levels > 40 mU/ml, and 11 (85%) of these required neonatal intensive care. Cord serum Epo correlates better with oxygen tension and pH at birth than with fetal growth and haematocrit, which are measures of chronic stress to the fetus.

Increased incidence of respiratory distress syndrome in babies of hypertensive mothers.

There is controversy over the effect of hypertension in pregnancy on the incidence of neonatal respiratory distress syndrome. We investigated the association between maternal hypertension and the incidence of respiratory distress syndrome in 268 very low birthweight babies of less than 34 weeks' gestation. A lower incidence of respiratory distress syndrome was associated with growth retardation and membrane rupture greater than 24 hours. Maternal hypertension was associated with an increased incidence of respiratory distress syndrome. We used the multiple logistic regression model to control for confounding variables, as the maternal and neonatal factors associated with respiratory distress syndrome were not evenly distributed between the two groups. After adjustment for birth weight, gestational age, growth retardation, and membrane rupture greater than 24 hours, the risk of developing respiratory distress syndrome was significantly greater in babies of hypertensive mothers. Significance was lost when labour before delivery and mode of delivery were taken into account. The increased incidence of respiratory distress syndrome in babies of hypertensive mothers may be due to the absence of labour before delivery because of the greater likelihood of caesarean section.

Pyloric stenosis: congenital or acquired?

Pyloric muscle dimensions were measured in 1400 consecutive newborn infants. Nine of these subsequently developed pyloric stenosis. Their pyloric measurements at birth were all within the normal range. Congenital preformed muscular hypertrophy does not appear to be present in babies who later develop pyloric stenosis.

Value of ultrasound in differentiating causes of persistent vomiting in infants.

A prospective study of abdominal ultrasound was undertaken in 100 consecutive infants who presented with a history of persistent vomiting aged 5 to 90 days. Each infant had a 'test feed' followed by an ultrasonographic scan of the pylorus at the cotside. On test feeding a palpable tumour was evident in 38 infants. On real time ultrasound using the criteria for diagnosing pyloric stenosis, these 38 infants as well as six others were documented as having pyloric stenosis. In the other 56 patients the vomiting settled in six and a barium examination was performed on the remaining 50. This confirmed gastro-oesophageal reflux in 46, two of whom had an associated hiatus hernia, one with a duodenal malrotation, and three were reported as normal. Ultrasound of the abdomen is an accurate, reliable, and rapid screening method to differentiate the causes of severe vomiting in infancy.

Power spectral analysis of the electrocardiogram in diabetic children.

In recent years it has been shown that alteration in heart rate variability can be used for the objective assessment of autonomic function in adult diabetic patients. Using a microcomputer based system for on-line monitoring and analysis of heart rate variability by power spectral analysis, 100 children with Type 1 (insulin-dependent) diabetes mellitus were studied. A highly significant negative correlation was identified between heart rate variability and duration of diabetes (r = -0.88, p less than 0.0001). The mean heart rate variability in patients with diabetes of duration 3 years or more was significantly lower in comparison to age-matched control subjects. A highly significant negative correlation was evident between heart rate variability and mean HbA1 in patients with duration of diabetes of 5 years or more. A mean HbA1 over 10% during this period was associated with the greatest reduction in heart rate variability. Serial measurements of heart rate variability in diabetic children may be of predictive value prior to the onset of symptomatic neuropathy.

Characterization of the three-compartment gel-entrapment porcine hepatocyte bioartificial liver.

A hybrid bioartificial liver device supporting a large mass of cells expressing differentiated hepatocyte metabolic capabilities is necessary for the successful treatment of fulminant hepatic failure. The three-compartment gel-entrapment porcine hepatocyte bioartificial liver was designed to provide "bridge" support to transplantation or until native liver recovery is achieved for patients with acute liver failure. The device is an automated mammalian cell culture system supporting 6-7 x 10(9) porcine hepatocytes entrapped in a collagen matrix and inoculated into the capillary lumen spaces of two 100 kDa molecular mass cut-off hollow fiber bioreactors. Gel contraction recreates a small lumen space within the hollow fiber which allows for the delivery of a nutrient medium. This configuration supported hepatocyte viability and differentiated phenotype as measured by albumin synthesis, ureagenesis, oxygen consumption, and vital dye staining during both cell culture and ex vivo application. The hollow fiber membrane was also shown to isolate the cells from xenogenic immunoglobulin attack. The gel-entrapment bioartificial liver maintained a large mass of functional hepatocytes by providing a three-dimensional cell culture matrix, by delivering basal nutrients through lumen media perfusion, and by preventing rejection of the xenocytes. These features make this device a favorable candidate for the treatment of clinical fulminant hepatic failure.

Gel-entrapment bioartificial liver therapy in galactosamine hepatitis.

A need exists for an effective, safe bioartificial liver to support patients in fulminant hepatic failure (FHF). The purpose of this study was to determine the treatment efficacy of the novel gel-entrapment porcine hepatocyte bioartificial liver (BAL) in a fatal model of canine hepatic failure. FHF was produced in 27- to 30-kg halothane-anesthetized dogs by bolus infusion of the hepatotoxin D-galactosamine (D-Gal). Three groups were studied during the 48-hr experiment: Group D-Gal (n = 5) received galactosamine, 1.0 g/kg, iv at Time O, Group HepBAL (n = 5) received D-Gal followed by continuous hemoperfusion with the BAL device loaded with approximately 6 billion viable pig hepatocytes starting at Time 24 hr, and three dogs served as healthy controls (Group Control) and received no galactosamine. The primary endpoints were survival and coma development. Group D-Gal demonstrated 100% mortality from liver failure by 42 hr, characterized by a progressive rise in liver enzymes, total bilirubin, ammonia, and lactate and associated with coagulopathy, hypoglycemia, coma, and brain death. BAL therapy significantly delayed the onset of coma and improved survival (median 47 hr vs D-Gal median 36 hr). A significant delay in the rise of lactate and ammonia was also noted. BAL therapy prolonged survival and improved both laboratory and clinical markers of fatal liver failure. These data indicate that this BAL may have clinical utility in supporting human liver failure.

An anesthetized model of lethal canine galactosamine fulminant hepatic failure.

A reproducible large animal model of fulminant hepatic failure was developed in the anesthetized dog by the administration of the amino sugar D-galactosamine. Galactosamine in 5% dextrose in water (D5W), was given as an intravenous bolus to 10 young male dogs weighing 27 to 30 kg. Three dogs that received an equal volume of D5W alone served as controls. Galactosamine at 0.5 g/kg (n = 5) produced significant biochemical evidence of liver injury with 100% survival at 48 hours. Galactosamine 1.0 g/kg (n = 5) yielded in 100% 48-hour mortality resulting from fulminant liver failure characterized by a progressive increase in liver enzymes, total bilirubin, ammonia, and lactate and associated coagulopathy, hypoglycemia, coma, and increased intracranial pressure. Necropsy showed liver pallor, ascites, and brain swelling. Liver histology showed significant hepatocellular necrosis. This clinically relevant large animal model will enable the quantitative evaluation of new technologies, such as the bioartificial liver, for the support of hepatic failure in humans.