Kevin P. Lally

Postoperative outcomes of extremely low birth-weight infants with necrotizing enterocolitis or isolated intestinal perforation: A prospective cohort study by the NICHD Neonatal Research Network

Objective:Purposes of this study were: 1) to compare mortality and postoperative morbidities (intra-abdominal abscess, wound dehiscence, and intestinal stricture) in extremely low birth weight (ELBW) infants who underwent initial laparotomy or drainage for necrotizing enterocolitis (NEC) or isolated intestinal perforation (IP); 2) to determine the ability to distinguish NEC from IP preoperatively and the importance of this distinction on outcome measures; and 3) to evaluate the association between extent of intestinal disease determined at operation and outcome measures. Background:ELBW infants who undergo operation for NEC or IP have a postoperative, in-hospital mortality rate of approximately 50%. Whether to perform laparotomy or drainage initially is controversial. Also unknown is the importance of distinguishing NEC from IP and the current ability to make this distinction based on objective data available prior to operation. Methods:A prospective, multicenter cohort study of 156 ELBW infants at 16 neonatal intensive care units (NICU) within the NICHD Neonatal Research Network. Results:Among the 156 enrolled infants, 80 underwent initial peritoneal drainage and 76 initial laparotomy. Mortality rate was 49% (76 of 156). Ninety-six patients had a preoperative diagnosis of NEC and 60 had presumed IP. There was a high level of agreement between the presumed preoperative diagnosis and intraoperative diagnosis in patients undergoing initial laparotomy (kappa = 0.85). The relative risk for death with a preoperative diagnosis of NEC (versus IP) was 1.4 (95% confidence interval, 0.99–2.1, P = 0.052). The overall incidence of postoperative intestinal stricture was 10.3%, wound dehiscence 4.4%, and intra-abdominal abscess 5.8%, and did not significantly differ between groups undergoing initial laparotomy versus initial drainage. Conclusions:Survival to hospital discharge after operation for NEC or IP in ELBW neonates remains poor (51%). Patients with a preoperative diagnosis of NEC have a relative risk for death of 1.4 compared with those with a preoperative diagnosis of IP. A distinction can be made preoperatively between NEC and IP based on abdominal radiographic findings and the patients age at operation. Future randomized trials that compare laparotomy versus drainage would likely benefit from stratification of treatment assignment based on preoperative diagnosis.

Laparotomy versus peritoneal drainage for necrotizing enterocolitis or isolated intestinal perforation in extremely low birth weight infants: outcomes through 18 months adjusted age.

OBJECTIVE. Extremely low birth weight (ELBW; ≤1000 g) infants with necrotizing enterocolitis (NEC) or isolated intestinal perforation (IP) are treated surgically with either initial laparotomy or peritoneal drain placement. The only published data comparing these therapies are from small, retrospective, single-center studies that do not address outcomes beyond nursery discharge. The objective of this study was to conduct a prospective, multicenter, observational study to (1) develop a hypothesis about the relative effect of these 2 therapies on risk-adjusted outcomes through 18 to 22 months in ELBW infants and (2) to obtain data that would be useful in designing and conducting a successful trial of this hypothesis. METHODS. A prospective, cohort study was conducted at 16 clinical centers within the National Institute of Child Health and Human Development Neonatal Research Network. To assist in risk adjustment, the attending pediatric surgeon recorded the preoperative diagnosis and intraoperative diagnosis and identified infants who were considered to be too ill for laparotomy. Predefined measures of short- and longer-term outcome included (1) either predischarge death or prolonged parenteral nutrition (>85 days) after enrollment and (2) either death or neurodevelopmental impairment on a standardized examination at 18 to 22 months adjusted age. RESULTS. Severe NEC or IP occurred in 156 (5.2%) of 2987 ELBW infants; 80 were treated with initial drainage, and 76 were treated with initial laparotomy. By 18 to 22 months, 78 (50%) had died; 112 (72%) had died or were shown to be impaired. Outcome was worse in the subgroup with NEC. Laparotomy was never performed in 76% (28 of 36) of drain-treated survivors. CONCLUSIONS. Drainage was commonly used, and outcome was poor. Our findings, particularly the risk-adjusted odds ratio favoring laparotomy for death or impairment, indicate the need for a large, multicenter clinical trial to assess the effect of the initial surgical therapy on outcome at ≥18 months.

Measured energy expenditure in critically III infants and young children

Technological limitations have impeded accurate energy expenditure assessment in critically ill infants and young children. Instead, a predicted energy expenditure (PEE) is derived based on weight, heat loss, activity, growth requirements, and degree of stress. This study compared actual measured energy expenditure (MEE) with conventional predicted values in 20 critically ill infants and children using a validated metabolic cart designed for use in this age group. All patients were studied either within 4 days of major surgery or during an acute disease process necessitating intensive care. All were severely stressed clinically and were studied while mechanically ventilated in a temperature-controlled environment. The study interval ranged from 1 to 12 hr and averaged 4 hr after a stabilization period of 30 min. The mean MEE was significantly lower than the mean PEE (52.2 +/- 16 kcal/kg/day vs 101.8 +/- 17 kcal/kg/day, P less than 0.001) with a mean MEE/PEE of 52.6 +/- 17% (range 26 to 92%). In a subgroup of 7 paralyzed patients, the mean MEE was significantly lower than in the 13 nonparalyzed patients when compared with PEE and predicted basal metabolic rate (PBMR). The coefficient of variance, conventionally recognized to be approximately 15% for PEE, averaged 6.35% for MEE in this study. These data indicate that if PEE is used as the sole guide for caloric repletion in the stressed infant or child, these patients will be substantially overfed.

Necrotizing fasciitis. A serious sequela of omphalitis in the newborn.

We reviewed all cases of omphalitis seen at Childrens Hospital of Los Angeles from 1961 to 1981. One hundred and forty patients were seen and, of these, eight had necrotizing fasciitis. All patients with necrotizing fasciitis acquired omphalitis at home, making the incidence of necrotizing fasciitis over 10% in patients with community acquired omphalitis. Most of the infants appeared relatively well on admission with no fever but had a marked leukocytosis. The disease rapidly spread to involve most of the abdominal wall over a period of several hours to days. Seven of the eight patients died (87.5%). Five patients were operated upon but despite extensive resection of involved tissue, four died within 24 hours of surgery. A polymicrobial flora of both gram positive and gram negative bacteria was recovered in all patients cultured. The high incidence of necrotizing fasciitis following omphalitis in the newborn with its attendant morbidity and mortality mandates close observation of these infants with early surgical intervention if there is any question of the diagnosis.

Hamartomas of the chest wall in infants

Chest wall hamartomas in infancy are rare lesions with distinct clinical, radiologic, and pathologic characteristics. Four cases treated at Childrens Hospital of Los Angeles are presented and previously reported cases are reviewed. Chest wall hamartomas arise antenatally and present as hard, immobile masses, which may cause respiratory insufficiency. An extrapleural mass arising from the ribs can be seen radiographically. Histologically, these lesions are hypercellular and consist of a disorganized array of mesenchymal tissues endogenous to the chest wall. Rapid growth may occur, but usually is self-limited. Chest wall hamartomas are usually benign. This series includes the malignant transformation of one of these lesions. En bloc resection is curative, but the large residual chest wall defect frequently results in scoliosis.

Indirect calorimetry in mechanically ventilated infants and children : measurement accuracy with absence of audible airleak

Objective:To establish the effect of an audible airleak (around an endotracheal tube) on oxygen consumption (Vo2) measurements in pediatric ICU patients. Design:Prospective trial comparing Vo2 measurements before and after deflation of the endotracheal tube cuff. Setting:Pediatric ICU in a large pediatric tertiary care center. Patients:Twenty critically ill infants and children receiving mechanical ventilatory support via cuffed endotracheal tube. Interventions:Deflation of endotracheal tube cuff. Measurements and Main Results:The presence (group 1, n = 9) or absence (group 2, n = 11) of an audible airleak with the cuff deflated was confirmed by two independent observers. The percent difference in Vo2 was calculated for both groups using the following formula: ([Vo2cuff up -Vo2 cuff down]/Vo2 cuff up × 100. An audible airlelk associated with cuff deflation (group 1) caused a significant (p = .0012) reduction of Vo2 by 45.6% (mean difference in Vo2 = 45.6%). In contrast, with no audible airleak after cuff deflation (group 2), only minimal changes in Vo2 (mean difference in Vo2 = −0.4%) were observed. Conclusions:These data suggest that if no audible airleak is detected, Vo2 determined by indirect calorimetry may be reliably measured in infants and children with a noncuffed endotracheal tube.

Surgical Management of Necrotizing Enterocolitis and Isolated Intestinal Perforation in Premature Neonates

Necrotizing enterocolitis (NEC) and isolated intestinal perforation (IP) are two relatively common disease conditions that require neonatal surgical therapy. The early mortality rate approaches 50%, and survivors frequently have growth and neurodevelopmental impairment. Much discussion has occurred regarding whether initial drain placement alone or laparotomy with resection of diseased intestine should be the initial surgical therapy. Several recent prospective studies have shown that the early mortality rate is likely not significantly different after either of these surgical approaches. Major morbidity, especially the likelihood for neurodevelopmental impairment, may be different in the two treatment groups. Further prospective trials are needed to further explore this question and are planned. Studies focusing on prevention of NEC and IP and also on improved medical treatment are needed to allow a major advance in the outcomes of infants with NEC and IP. As these studies are being performed, trials evaluating existing medical and surgical therapies are also needed.

Persistent pulmonary hypertension complicating cystic adenomatoid malformation in neonates

Neonates with congenital diaphragmatic hernia (CDH) are known to be susceptible to stress-induced persistent pulmonary hypertension (PPHN). Congenital cystic adenomatoid malformations (CCAMs) may also present as respiratory distress in the newborn. Intubation and mechanical ventilation cause clinical deterioration because of air trapping within cystic spaces; these patients require prompt lobectomy. PPHN has not been commonly associated with CCAM. Three patients with CCAM were encountered who developed PPHN postlobectomy. Three newborns, 36 to 38 weeks gestation, presented with respiratory distress. Two had diagnosis of thoracic tumors on fetal ultrasound (22 and 33 weeks). Chest x-ray at birth confirmed cystic intrathoracic tumors in all and they underwent immediate thoracotomy and lobectomy (1 right upper, 1 left lower, 1 left upper). The patients were stable for 4 hours to 5 days postoperatively and then developed findings consistent with PPHN by cardiac echocardiography and required extracorporeal membrane oxygen (ECMO) support. ECMO was required for 66.5 to 120 hours. Each patient was successfully weaned to conventional ventilatory support. The clinical course of these patients was similar to those with CDH who undergo immediate surgery. The stress of surgical intervention combined with hypoxia and hypercarbia stimulates a hyperactive pulmonary vasculature and the development of PPHN. ECMO provides an effective adjunct to support patients with PPHN on the basis of congenital cystic adenomatoid malformations.

Primary endodermal sinus (yolk sac) tumor of the falciform ligament.

Extragonadal yolk sac tumors (YSTs) are uncommon and YSTs of the liver are exceedingly rare, with only three reported cases in the literature. A case is described of primary YST of the falciform ligament extending into the left lobe of the liver in a 14-month-old boy. This is the first reported case of primary YST arising within the falciform ligament. The patient underwent an exploratory laparotomy after presenting with hemoperitoneum. An extremely friable and necrotic tumor was found extending from the falciform ligament into the liver. The tumor was debulked and the patient received 5 months of chemotherapy employing a modified Einhorn regimen. After a partial response to chemotherapy the patient had a second-look laparotomy, at which time a left hepatic lobectomy and en bloc resection of the falciform ligament was performed in order to remove residual tumor. At the present time the patient has no signs of metastases and is alive and well 2 years after his presentation.