Robert M. Arensman

A correlation of pulmonary hypoplasia, mean airway pressure, and survival in congenital diaphragmatic hernia treated with extracorporeal membrane oxygenation

Thirty infants with congenital diaphragmatic hernia (CDH) who required therapy within the first day of life were treated in our institution over the past 3 years. Eighteen of these infants were not treated with extracorporeal membrane oxygenation (ECMO). Survival in this group was 83%. Twelve infants were treated with ECMO. Seven (58%) were weaned from ECMO and ventilator support with six (50%) long-term survivors. Minimum preoperative alveolar-arterial oxygen gradient (AaDO2), maximum postoperative mean airway pressure (MAP), and pulmonary hypoplasia were evaluated. Bohn et al have prospectively shown that the relationship of PaCO2 to mechanical ventilatory requirements accurately predicted survival in a group of 58 infants with CDH in whom ECMO was not a therapeutic option. This criteria would predict nonsurvival in all 12 of our patients treated with ECMO, including the seven survivors. Differences between our ECMO and non-ECMO groups were statistically significant for all three criteria. All P values less than .05. Morphometric analysis of the lungs of all ECMO nonsurvivors revealed hypoplastic ipsilateral lungs by lung weight to body weight ratios and radial alveolar counts when compared with experimental and historical controls (P less than .05). The contralateral lung was hypoplastic in 80% of the nonsurvivors. There is a strong correlation between the maximum postoperative MAP and the degree of contralateral pulmonary hypoplasia (r = .03, P = .02). We conclude that the maximum postoperative MAP is an accurate predictor of survival in the treatment of CDH and can be correlated with the degree of pulmonary hypoplasia.(ABSTRACT TRUNCATED AT 250 WORDS)

Extracorporeal membrane oxygenation for nonneonatal respiratory failure

Extracorporeal membrane oxygenation (ECMO) has been used for 20 years in neonates and children with cardiac and respiratory failure. The number of neonates treated with ECMO has increased exponentially, but the number of older children treated is small. The selection and exclusion criteria for pediatric ECMO are poorly defined, and the results vary because of variable selection criteria and institutional experience with the technique. In order to help define the role of pediatric ECMO, we reviewed our experience in noneonatal pediatric respiratory failure. We have treated 22 patients ranging in age from 1 to 105 months and ranging in weight from 3 to 35 kg. Eighteen patients met the criteria for adult respiratory distress syndrome, two had respiratory syncytial virus pneumonia, and one had severe barotrauma complicating the management of reactive airway disease. All patients were considered by the referring institutions and by us to be failing conventional management as evidenced by hypoxia, hypercarbia, excessive ventilatory pressures, or progressive barotrauma. All were considered likely to die with continued conventional management. Sixteen of the 22 patients had complications (73%), but half of the last 10 patients had no complications. Hemorrhagic complications occurred in 12 patients. Mechanical complications included membrane failure, raceway rupture, pump malfunction, and improper cannula positioning. Other complications included culture-proven infection and renal failure. Eleven of the 22 patients survived (50%); nine of the last 12 survived (75%). These results suggest that ECMO may be a useful technique in selected pediatric patients with respiratory failure. Survival and complication rates improve as experience with the technique increases.

Improving Survival in the Treatment of Congenital Diaphragmatic Hernia

Thirty-two infants were treated for congenital diaphragmatic hernia at our institution from 1979 to 1984. Eight were in no or minimal distress at birth and had operative intervention when they were more than 24 hours old; survival was 100%. The remaining 24 neonates required immediate intubation and ventilation followed by operation at less than 12 hours of age. Overall survival was 54%; survival was 31% (4 of 13 patients, Group 1) in the first three years of the series and 82% (9 of 11 patients, Group 2) in the last three years (p less than 0.001). Apgar score, gestational age, birth weight, and incidence of associated congenital heart disease were equal for the two groups (all, p greater than 0.05). The two groups also were examined with reference to alveolar-arterial oxygen differences P(A-a)O2 and mean airway pressure (MAP). The best preoperative P(A-a)O2 was greater than 600 mm Hg for 7 neonates in Group 1 and 6 in Group 2, and survival was 0% and 71%, respectively (p less than 0.001). Infants with a postoperative MAP of 13 cm H2O or greater had a higher mortality (100% in Group 1 and 50% in Group 2, p greater than 0.05). Our treatment protocol was studied to determine those methods related to improved survival. Sodium bicarbonate infusion was used earlier in Group 2 as a prophylaxis against persistent fetal circulation (PFC) (p greater than 0.05). The incidence of severe PFC dropped from 85 to 54% (p greater than 0.05). Higher ventilator rates rather than pressures were used to achieve equally effective ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical management of the infant with mesenchymal hamartoma of the chest wall

Mesenchymal hamartoma of the chest wall is a rare lesion that presents as a chest wall mass. Four infants are reported, three of whom underwent extensive chest wall resection.

Serum vascular endothelial growth factor as a surveillance marker for cellular rejection in pediatric cardiac transplantation.

BACKGROUND Early detection and treatment of acute rejection in cardiac transplant recipients significantly improves long-term survival. Endomyocardial biopsy is used routinely for diagnosing allograft rejection; however, in young children, this procedure carries some risk. We evaluated serum vascular endothelial growth factor (VEGF) as a potential surveillance marker of acute cellular rejection. METHODS Blood samples (n=62) were analyzed from 23 patients and compared with controls (n=18) using an ELISA for VEGF. Results were correlated with endomyocardial biopsy rejection grades. RESULTS Mean baseline VEGF levels of the transplant population were consistently higher than controls. Serum VEGF levels were significantly higher during acute cellular rejection when compared with the non-rejecting transplant group (700.7+/-154 pg/ml vs. 190.5+/-29 pg/ml). VEGF decreased two- to eightfold after immunosuppressive therapy in 9 of 11 rejection episodes. CONCLUSIONS These data suggest that VEGF may play a role in the pathogenesis of acute allograft rejection and it may serve as a reliable serologic surveillance marker.

Extracorporeal membrane oxygenation for newborn respiratory failure

Respiratory failure is the leading cause of death in the newborn. Conventional therapy is very successful with 80% of infants weaned from ventilatory support. For neonates with severe respiratory failure, unresponsive to maximal medical therapy, extracorporeal membrane oxygenation (ECMO) offers an alternative means of management. Venoarterial bypass is achieved by cannulating the right atrium via the internal jugular vein and the aortic arch via the right common carotid artery. A 5-inch roller pump is used to circulate the blood through a 0.4 or 0.8 m2 silicone membrane lung. Management includes heparinization, intravenous alimentation, antibiotic coverage, and reduction of FiO2 and airway pressure. Thirty infants aged 12 to 186 hours were placed on ECMO. Each met strict criteria designed to predict greater than 90% mortality. Time on bypass ranged from 37 to 250 hours. Success, defined by weaning from ECMO and ventilatory support, was achieved in 23. Twenty-one remain alive; 18 have excellent outcome with normal growth and development although follow-up is short (1 to 19 mos). These results corroborate reports from the pioneers of the technique and further support the use of ECMO for neonates with respiratory failure unresponsive to conventional therapy.

Closing arguments for gastroschisis: management with silo reduction.

Abstract Background: There are two approaches to close gastroschisis. Primary closure (PC) is reduction and fascial closure; silo closure (SC) places viscera in a preformed-silo and reduces the contents over time. We have shifted from PC to SC. This study compared the outcomes of these two techniques. Methods: Records of babies with gastroschisis from 1994–2004 were reviewed. Closure type, ventilator days, days to full-feeds, hospital days, complications, and mortality were recorded. Results: Twenty-eight patients underwent PC; 20 patients had SC. Differences in ventilator days, days to full-feeds, and hospital days were not statistically significant. Nine PC patients developed closure-related complications vs. none in SC (P<0.05). Eight PC vs. two SC patients had non-closure-related complications (P<0.05). Four PC vs. zero SC patients developed necrotizing enterocolitis (P<0.05). Five PC vs. one SC patients had ventral hernia (P<0.05). No patient died. Conclusion: PC resulted in higher incidence of reclosure, non-closure-related complications, and necrotizing enterocolitis. Consequently, we recommend SC as the preferred treatment.

Pediatric extracorporeal membrane oxygenation in posttraumatic respiratory failure.

The leading cause of death in the pediatric population in the United States is trauma. A retrospective review of patients treated with extracorporeal membrane oxygenation (ECMO) for traumatic respiratory failure was performed. Eight children were treated at the Ochsner Medical Foundation and additional data on six children were available from the National Registry. Six children developed respiratory failure as a result of blunt trauma and eight as a result of near drowning. Standard venoarterial ECMO was used with a circuit very similar to that used in neonatal ECMO. Vascular access was via the common carotid artery and the internal jugular vein. Ventilatory support was weaned to minimal settings during ECMO. Central hyperalimentation and systemic antibiotics were used in all of the cases. Four of six children survived in the blunt trauma group; three of eight children survived in the near drowning group. Although significant conclusions cannot be drawn from a small group of patients the average pre-ECMO PO2 for survivors was 87 mm Hg, whereas for nonsurvivors the average PO2 was only 46 mm Hg. Ventilatory support for both groups was not remarkably different, and the average PCO2 was lower in the nonsurvivor group. The cause of death in this group of patients is usually multisystem organ failure. In the four patients treated at Ochsner who did not survive, all had positive blood cultures and presumed systemic sepsis. ECMO has been demonstrated to be very successful in neonatal respiratory failure. Predicting mortality and morbidity in pediatric respiratory failure has been more difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

Omphalopagus Twins With Covered Cloacal Exstrophy

The incidence of conjoined twins is approximately 1/100,000 births and 70% of the twins are female.’ Approximately 40 to 60% of conjoined twins are stillborn and an additional 35% survive only 1 day. These early deaths generally occur in the most severely malformed twins, especially those with thoracopagus joining and major cardiopulmonary malformation. Approximately 35% of the twins are the omphalopagus type, which comprises a wide spectrum ranging from shared liver, intestines and bladder to a mere skin bridge.* We report the anatomical findings and separation of the eighteenth reported case of minimally conjoined omphalopagus twins.3

Polysplenia syndrome: Spectrum of gastrointestinal congenital anomalies

This report describes four children with polysplenia syndrome seen in our hospital during the past year. Each had gastrointestinal abnormalities as their predominant problem, and two presented with gastrointestinal duplications not previously reported with this syndrome.