The Viladot implant in flatfooted children.

In 1991, Viladot described an implant for the treatment of painless flatfeet in children. This was inserted through a double approach to allow the talus to function while limiting its ability to slide off the calcaneus. The wineglass shaped prosthesis was inserted into the sinus tarsi with a tibialis posterior advancement and soft tissue correction to allow the foot to adopt a neutral position. This is in keeping with other procedures described for the correction of flatfoot. Viladot reported excellent results in 234 feet operated on in such a manner using clinical, radiological and photopodographic parameters. In Sheffield, over three years, 22 implants were inserted for similar painless flatfeet in children. The results were assessed using clinical, radiological and pedobarographic parameters. Viladot was able to demonstrate an improvement in all cases, clinically, radiologically and photopodographically with little or no discomfort and a return to preoperative levels of activity including sport. We found that in all cases, postoperative pain was a major feature which limited activity in all but 2 feet and which reduced the ability to take part in sport and other preoperative pastimes. Unlike Viladot, we were unable to demonstrate consistent improvements radiologically. Pedobarographically, the loading of the first metatarsal head remained unchanged and the centre of pressure was corrected in only 14%.

Acute carpal tunnel syndrome as a complication of oral anticoagulant therapy.

Acute carpal tunnel syndrome is well recognized in patients with haemophilia and conservative management with factor replacement and temporary splinting is recommended. There have, however, been very few reported cases of acute carpal tunnel syndrome as a complication of oral anticoagulant therapy. We describe such a case in a patient on long-term warfarin anticoagulation, drawing attention to particular features of the history and clinical findings. In contrast to previous reports, we recommend prompt decompression under local anaesthesia and continuation of the anticoagulant therapy.

Mesenteric defects as a cause of intestinal volvulus without malrotation and as the possible primary etiology of intestinal atresia.

Mesenteric defects can lead to intestinal volvulus even when the midgut is normally rotated. There are two types of mesenteric defects: basilar, in which the entire base of the mesentery is involved, and segmental, in which only an isolated portion of the mesentery is affected. These defects can present at any age, and the clinical symptoms depend on the extent of the disease and the amount of intestine involved in the volvulus. In the newborn, the basilar defects have clinical signs and symptoms similar to those of midgut volvulus secondary to malrotation. Similar to midgut volvulus secondary to malrotation, this is a surgical emergency. In older patients, basilar defects can be misdiagnosed because of the normal placement of the ligament of Treitz and because of failure to consider mesenteric defects as a possible cause. The treatment for basilar mesenteric defects is intestinal fixation. Intestinal volvulus secondary to segmental defects always presents as intestinal obstruction. In the newborn, these lesions may be indistinguishable from intestinal atresia. Older children present with intestinal obstruction of an unknown cause. Resection of the affected intestine is the treatment for segmental mesenteric defects. Intestinal mesenteric abnormalities as a cause of intestinal atresia unifies under one etiology all the lesions observed in intestinal atresia. Although this theory does not rule out other causes of intestinal atresia, intestinal mesenteric defects may be the primary condition under which intestinal atresia occurs.

Mediastinal cystic hygroma: prenatal decompression with neonatal resection and recurrence at 19 months of age.

A case of an anterior mediastinal cystic hygroma detected prenatally at 22 weeks' gestation is reported. Because of progressive nonimmune hydrops, cardiac compromise, and mediastinal shift compressing the lungs, in utero decompression was successfully performed at 24 weeks. This newborn infant was delivered at 37 weeks' gestation with no respiratory distress. Operative excision of a large thoracic cystic hygroma was performed shortly after birth. At 19 months of age, this patient appeared with unilateral wheezing and fever. Operative findings confirmed recurrence of a cystic hygroma.

An association of pulmonary hypoplasia with unilateral agenesis of the diaphragm.

During a period of 5 years, 33 newborns with congenital diaphragmatic hernia were treated. Three groups presenting with respiratory distress in the delivery room were identified. These included 8 newborns with agenesis (group 1) and 4 newborns with nonagenesis (group 2), all of whom died. There were 19 nonagenesis survivors (group 3), giving an overall survival rate of 61%. Two newborns who presented beyond 6 hours of life were excluded. No one specific arterial blood gas value or ventilation parameter obtained preoperatively could predict survival. Postmortem right and left lung weights, lung/body weight ratio, and radial alveolar counts demonstrate that agenesis is a unique subgroup with profound pulmonary hypoplasia and a dismal prognosis.

Segmental absence of small intestinal musculature.

Three instances of segmental absence of small intestinal musculature are described. Based on their clinical and pathological features and on the 12 cases previously described in the English literature, these can be classified into two groups: primary and secondary. In the primary group, the etiology is unknown, the onset of symptoms is acute, and there are no pathologic findings in the remaining layers of the small bowel except for superimposed perforation, or intussusception. In the secondary group, there is a longer history of intestinal symptoms and of multiple surgical procedures. Histologically, there may be ischemic necrosis of remaining layers, fibrosis, calcification, chronic inflammation, and presence of macrophages. These findings indicate secondary destruction of muscle layers due to ischemia and/or infarction, interruption of the blood supply, or trauma.

Ileal perforation due to arteriovenous malformation in a premature infant.

Gastrointestinal arteriovenous malformations (AVM) in children are most commonly associated with bleeding. Although not previously reported, we present a case of an AVM associated with intestinal perforation in a premature infant.

Adenosine reversal of in vivo hepatic responsiveness to insulin.

Modulation by adenosine of hepatic responsiveness to insulin was investigated in vivo in 10 healthy mongrel dogs of both sexes by determining net hepatic glucose output (NHGO) in response to insulin during the presence or absence of exogenous adenosine infusion. In addition, two separate series of experiments were performed to study the effect of adenosine (n = 7) or glucagon (n = 5) on NHGO. Basal NHGO, quantitated via the Fick principle, was significantly decreased by insulin infusion (4 U/min; 4.8 +/- 0.6 vs. -1.7 +/- 2.6 mg.kg-1.min-1, P less than 0.05). The addition of an intrahepatic arterial infusion of adenosine (10 mumol/min) during insulin infusion caused glucose output to return to basal levels (insulin, -1.7 +/- 2.6 mg.kg-1.min-1; insulin + adenosine, 3.8 +/- 1.6 mg.kg-1.min-1, P less than 0.05). The addition of intrahepatic arterial saline (control) during insulin infusion had no effect on insulin's action (insulin, -1.0 +/- 1.9 mg.kg-1.min-1; insulin + saline, -1.2 +/- 1.6 mg.kg-1.min-1, P greater than 0.05). Hepatic glucose, lactate, and oxygen deliveries were not affected during either insulin or insulin plus adenosine infusion. Intrahepatic arterial infusion of adenosine alone had no effect on NHGO, whereas intrahepatic arterial infusion of glucagon alone stimulated glucose output approximately fivefold (basal, 2.7 +/- 0.4 mg.kg-1.min-1; glucagon, 15.5 +/- 1.2 mg.kg-1.min-1, P less than 0.01). These results show that adenosine completely reversed the inhibition by insulin of NHGO. These data suggest that adenosine may act as a modulator of insulin action on the liver.

The heated dorsal hand vein: an alternative arterial sampling site.

Studies of substrate flux, isotope activity and metabolic balance frequently require arterial sampling. We evaluated: (1) whether substrate concentrations obtained from heated dorsal hand veins (HDHV) were comparable to samples obtained from the radial artery, (2) whether heat sufficient to arterialize HDHV altered contralateral forearm blood flow thus affecting flux calculations, (3) whether a +14 heating pad equaled a cumbersome +700 heating chamber, and (4) whether HDHV showed a dose-response curve to varying heat loads. In 12 normals, dorsal hand temperature was raised from 31.8 +/- 0.6 degrees C to 39.8 +/- 0.8 degrees C (chamber) and 39.3 +/- 0.3 degrees C (pad). Basal contralateral forearm blood flow (3.37 +/- 0.7 ml/100 ml tissue/min) was not significantly altered in the chamber (3.39 +/- 0.5 ml) or the pad (3.44 +/- 0.5 ml). Skin temperature of the unheated hand, an index of superficial blood flow (31.5 +/- 0.7 degrees C) did not change significantly in the chamber (31.6 +/- 0.7 degrees C) or the pad (31.2 +/- 0.7 degrees C). Forearm blood flow did not change with heating in eight postoperative patients. Comparative arterial and HDHV blood gases and 10 metabolic substrates from simultaneously drawn samples at various temperatures showed HDHV PO2 approached but did not equal arterial PO2 at temperatures greater than 39 degrees C. Glucose, amino acid, and substrate concentrations were comparable at 39 degrees C and did not change with increasing temperature. HDHV can reliably determine arterial substrate concentrations using an inexpensive heating pad. In cool environments (20-22 degrees C), contralateral forearm blood flow is not significantly altered. There is no benefit to heating the hand above 39 degrees C.

Artificial beta-cell promotes positive nitrogen balance and whole body protein synthesis in insulin-dependent diabetic subjects.

To assess the effects of artificial beta-cell-directed insulin therapy on protein metabolism in patients with diabetes mellitus, nitrogen balance, urea production, and whole body protein turnover were determined in five type I insulin-dependent subjects and five age- and sex-matched controls. Each diabetic participant was studied over two 4-day periods while receiving conventional insulin therapy (one or two daily injections of short and intermediate acting insulin) or insulin delivered by the artificial beta-cell. While the diabetic participants received conventional insulin therapy, nitrogen balance, urea production, whole body protein turnover, and protein synthesis and breakdown rates did not differ significantly from the control group. However, when the same subjects were on artificial beta-cell-directed insulin therapy, they manifested a significant net positive nitrogen balance of over 2 g/day. This change in nitrogen balance was largely due to a fall in urea nitrogen production from 174 +/- 6 to 140 +/- 13 mg/kg body weight per day (p less than 0.05). In addition, while artificial beta-cell therapy did not affect whole body protein turnover or breakdown rates, a significant rise (2.1 +/- 0.2 to 2.4 +/- 0.1 g/kg per day) in whole body protein synthesis was observed (p less than 0.05). Thus when compared to conventional insulin treatment, artificial beta-cell-directed insulin therapy was associated with a 14% increase in the rate of protein synthesis and a decrease of 20% in urea nitrogen production, leading to a net positive nitrogen balance.

Pulmonary agenesis (aplasia), esophageal atresia, and tracheoesophageal fistula: a different treatment strategy.

This is a report of a patient with esophageal atresia, distal tracheoesophageal fistula, and right pulmonary agenesis who survived for 10 months. Death was due to progressive respiratory failure following a complicated clinical course. Several lessons were learned. First, the remaining lung is at high risk. Since the number of respiratory units in these infants is already decreased, the loss of more units has a more profound effect than in an otherwise healthy child. Second, while the establishment of esophageal continuity is important, all attempts to perform an esophagoesophagostomy should be abandoned if doing so further jeopardizes the solitary lung. Third, since all of these children have some degree of tracheomalacia, early tracheostomy should be considered. The tracheostomy will not only act as a tracheal stent but will also avoid progressive laryngeal pathology, which would result from long-term endotracheal intubation.

Insulin stimulates branched chain amino acid uptake and diminishes nitrogen flux from skeletal muscle of injured patients.

Resistance to insulin-mediated glucose disposal occurs in uninjured skeletal muscle of trauma patients but the effect of insulin on the accelerated proteolysis of trauma is unknown. We examined the influence of insulin on forearm amino acid and substrate exchange in five normals and four trauma patients using the hyperinsulinemic glucose clamp technique. Forearm substrate and amino acid flux (Q, nM/100 ml tissue/min), the product of blood flow and arterial deep venous concentration difference, was calculated before and during insulin infusion. Total nitrogen release (NQ, nM/100 ml tissue/min) was calculated as the algebraic sum of all nitrogen groups contained in the amino acids released. Among normal subjects, total nitrogen release from the forearm did not change (581 +/- 197 nM/100 ml tissue/min to 1167 +/- 455) during insulin infusion nor did total branched chain amino acid flux (0 +/- 30 nM/100 ml/min to 106 +/- 36). Under conditions of hyperinsulinemia, neither glutamine nor alanine changed in control subjects. In trauma patients, total nitrogen release (3843 +/- 1383 nM/100 ml/min) was inhibited during insulin administration (819 +/- 314, P less than 0.05). Total branched chain amino acid flux went from a net release of 460 +/- 134 nM/100 ml/min to a net uptake of 10 +/- 82 (P less than 0.05). In patients, statistically significant (P less than 0.05) differences were seen in individual amino acids as well. Forearm nitrogen flux was directly related to total branched chain amino acid flux in patients (r2 = 0.89). Additional studies in normals (n = 4) at higher insulin infusion rates confirmed that these effects were unique to injured subjects and not an effect of the insulin dose. Insulin attenuates the accelerated release of skeletal muscle amino acid in trauma patients. This effect may be mediated in part by facilitated branched chain amino acid uptake. The manipulation of both insulin and branched chain amino acid concentrations may provide a method to reduce post-traumatic protein catabolism.

Juxtapancreatic intestinal duplications with pancreatic ductal communication: a cause of pancreatitis and recurrent abdominal pain in childhood.

Pancreatic duplications with ductal communications should be included in the differential diagnosis of any child presenting with recurrent abdominal pain of unknown etiology and should be considered as a possible cause of pancreatitis in childhood. Such duplications most likely arise from nonregressing diverticula of the pancreatic bud during embryologic development. Their clinical presentation is unique from other duplications because of their anatomic association with the pancreatic duct. Pain and weight loss are the major presenting complaints, although many patients have nausea and vomiting. Serum chemistries, in particular the serum amylase, are usually normal and are of little help in the differential diagnosis. Radiographic evaluation has not been particularly helpful in the past. ERCP, ultrasonic examination, and CT scan show great promise, however. Operative intervention should be tailored for the individual patient. The operation performed will depend upon operative findings. Intraoperative pancreatograms or cystograms are very helpful in differentiating these cysts from others at the time of operation. Pathologically, most of the duplications have a thickened muscular coat that usually has some evidence of inflammation. They are usually lined with gastric mucosa. Except in the most severe cases, the pancreas is histologically normal, suggesting that most of the pain experienced by these patients is secondary to inflammation within the duplication. The inflammatory response may completely destroy the mucosal lining and cause fibrosis within the muscular coat of the duplication. In those instances, these lesions cannot be differentiated from pancreatic pseudocyst. This may account for some of the "idiopathic" pseudocysts reported in the literature.

The pulmonary hemodynamic response to perioperative anesthesia in the treatment of high-risk infants with congenital diaphragmatic hernia.

The continuing high mortality in congenital diaphragmatic hernia led us to study the cardiopulmonary disturbances associated with this lesion. Since these infants infrequently have right-to-left shunting in the operating room, we adopted a treatment protocol of: continuing general anesthesia in the postoperative period using fentanyl and pancuronium; cardiac catheterization postoperatively, including placement of a pulmonary artery line and a pulmonary angiogram; rapid frequency ventilation; moderate fluid restriction; and avoidance of vasodilators until other means of management had clearly failed. Fourteen high-risk infants, presenting within 6 hours of birth, were studied and compared to 17 high-risk infants, who served as historical controls. As revealed by the physiologic data acquired in the catheterization laboratory, high-risk infants divided into "Responder" and "Nonresponder" groups. Seven of 10 "Responders" actually shunted left to right during the catheterization, demonstrating a low pulmonary vascular resistance. Seven of 10 subsequently demonstrated significant right-to-left shunting at the level of the ductus and the foramen ovale, indicating the hyperreactivity of the pulmonary vascular bed. All but one was managed successfully by ventilatory adjustments and deepening of the level of anesthesia. "Nonresponders" had a fixed right-to-left shunt unresponsive to any medical or ventilatory manipulation. All "Nonresponders" died. Pulmonary angiography suggested a smaller diameter of the affected pulmonary artery compared to the main pulmonary artery in the "Nonresponders." This implies true hypoplasia resulting in a vasculature too small to accept a full cardiac output. Survival in the treatment group "Responders" was eight of 10 (80%) v seven of 14 (50%) in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)