Core outcome set for perinatal interventions for congenital diaphragmatic hernia

OBJECTIVE

To develop a core set of prenatal and neonatal outcomes for clinical studies evaluating perinatal interventions for congenital diaphragmatic hernia, using a validated consensus-building method.

METHODS

An international steering group comprising 13 leading maternal-fetal medicine specialists, neonatologists, pediatric surgeons, patient representatives, researchers and methodologists guided the development of this core outcome set. Potential outcomes were collected through a systematic review of the literature and entered into a two-round online Delphi survey. A call was made for stakeholders with experience of congenital diaphragmatic hernia to review the list and score outcomes based on their perceived relevance. Outcomes that fulfilled the consensus criteria defined a priori were discussed subsequently in online breakout meetings. Results were reviewed in a consensus meeting, during which the core outcome set was defined. Finally, the definitions, measurement methods and aspirational outcomes were defined in online and in-person definition meetings by a selection of 45 stakeholders.

RESULTS

Overall, 221 stakeholders participated in the Delphi survey and 198 completed both rounds. Fifty outcomes met the consensus criteria and were discussed and rescored by 78 stakeholders in the breakout meetings. During the consensus meeting, 93 stakeholders agreed eventually on eight outcomes, which constituted the core outcome set. Maternal and obstetric outcomes included maternal morbidity related to the intervention and gestational age at delivery. Fetal outcomes included intrauterine demise, interval between intervention and delivery and change in lung size in utero around the time of the intervention. Neonatal outcomes included neonatal mortality, pulmonary hypertension and use of extracorporeal membrane oxygenation. Definitions and measurement methods were formulated by 45 stakeholders, who also added three aspirational outcomes: duration of invasive ventilation, duration of oxygen supplementation and use of pulmonary vasodilators at discharge.

CONCLUSIONS

We developed with relevant stakeholders a core outcome set for studies evaluating perinatal interventions in congenital diaphragmatic hernia. Its implementation should facilitate the comparison and combination of trial results, enabling future research to better guide clinical practice. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Association of timing of congenital diaphragmatic hernia repair with survival and morbidity for patients not requiring extra-corporeal life support

BACKGROUND

While physiologic stabilization followed by repair has become the accepted paradigm for management of congenital diaphragmatic hernia (CDH), few studies have examined the effect of incremental changes in operative timing on patient outcomes. We hypothesized that later repair would be associated with higher morbidity and mortality.

METHODS

Data were queried from the CDH Study Group (CDHSG) from 2007-2020. Patients with chromosomal or cardiac abnormalities and those who were never repaired or required pre-repair extra-corporeal life support (ECLS) were excluded. Time to repair was analyzed both as a continuous variable and by splitting the cohort into top/bottom percentiles. The primary outcome of interest was in-hospital mortality. Secondary outcomes included need for and duration of post-repair ventilatory and nutritional support.

RESULTS

A total of 4,104 CDH infants were included. Median time to repair was 4 days (IQR 2-6). On multivariable analysis, high-risk (CDHSG stage C/D) defects and lower birthweight predicted later repair. Overall, in-hospital mortality was 6%. On univariate analysis, there was no difference in the number of days to repair between survivors and non-survivors. On risk-adjusted analysis, single-day changes in day of repair were not associated with increased mortality. Later repair was associated with longer time to reach full oral feeds, increased post-repair ventilator days, and increased need for tube feeds and supplementary oxygen at discharge.

CONCLUSIONS

For infants with isolated CDH not requiring pre-operative ECLS, there is no difference in mortality based on timing of repair, but single-day delays in repair are associated with increased post-repair duration of ventilatory and nutritional support.

Does a highest pre-ductal O(2) saturation <85% predict non-survival for congenital diaphragmatic hernia?

OBJECTIVE

To analyze operative repair, extracorporeal membrane oxygenation (ECMO) and survival rates based on highest pre-ductal oxygen saturation (Pre-O(2)SAT) in a large infant cohort reported to Congenital Diaphragmatic Hernia Study Group Registry between 2000 and 2010.

STUDY DESIGN

Analyzed data included gestational age, birth weight, defect side and size, repair, ECMO use, survival and highest reported PaO(2) and Pre-O(2)SAT in first 24 h of life. We excluded 614 infants due to severe anomaly. Pre-O(2)SAT data were available for 1672 infants.

RESULT

Among infants with highest Pre-O(2)SAT value <85%, survival (24/105=23%) and repair (55/105=52%) rates were significantly decreased compared with infants with higher values. Survival increased to 44% for infants with highest Pre-O(2)SAT<85% who underwent operative repair. Of these, 83% (20/24) required ECMO support compared with 15% (144/961) of survivors with Pre-O(2)SAT>99% (P<0.001). The lowest reported Pre-O(2)SAT with survival was 32% and for survival without ECMO was 52%.

CONCLUSION

A reported highest Pre-O(2)SAT<85% in the first 24 h of life was not uniformly fatal; but survival of infants with Pre-O(2)SAT<85% was associated with high ECMO use and prolonged hospitalization.

Hyperglycemia and morbidity and mortality in extremely low birth weight infants

OBJECTIVE

The purpose of this study was to determine the association between hyperglycemia and mortality and late-onset infections (>72 h) in extremely low birth weight (ELBW) infants.

STUDY DESIGN

Retrospective analysis of a prospective cohort study of 201 ELBW infants who survived greater than 3 days after birth. Mean morning glucose levels were categorized as normoglycemia (<120 mg/dl), mild-moderate hyperglycemia (120 to 179 mg/dl) and severe hyperglycemia (> or =180 mg/dl). Hyperglycemia was further divided into early (first 3 days of age) and persistent (first week of age). Logistic regression was performed to assess whether hyperglycemia was associated with either mortality or late-onset culture-proven infection, measured after 3 and 7 days of age.

RESULTS

Adjusting for age, the odds ratio (OR) for either dying or developing a late infection was 5.07 (95% confidence interval (CI): 1.06 to 24.3) for infants with early severe hyperglycemia and 6.26 (95% CI: 0.73 to 54.0) for infants with persistent severe hyperglycemia. Adjusting for age, both severe early and persistent hyperglycemia were associated with increased mortality. Among survivors, there was no significant association between hyperglycemia and length of mechanical ventilation or length of hospital stay. Persistent severe hyperglycemia was associated with the development of Stage II/III necrotizing enterocolitis, after adjusting for age and male gender (OR: 9.49, 95% CI: 1.52 to 59.3).

CONCLUSION

Severe hyperglycemia in the first few days after birth is associated with increased odds of death and sepsis in ELBW infants.

Surgery-associated complications in necrotizing enterocolitis: A multiinstitutional study

PURPOSE

This study was designed to evaluate the wound and stomal complication rate associated with surgical intervention in infants with necrotizing enterocolitis (NEC).

METHODS

Comprehensive demographic and perioperative data were collected prospectively from 4 separate university hospitals on 51 infants with surgically treated NEC. The postoperative complication rate included wound (infection, dehiscence) and stomal (prolapse, retraction, necrosis, stricture) problems. For analysis, patients were grouped based on gestational age less than 28 weeks (group I, n = 30) and >/=28 weeks (group II, n = 21). Z-score analysis was used for intergroup evaluation.

RESULTS

Significantly more infants in group I (21 of 30 [70%] versus group II, 6 of 21 [29%]; P <.001) were treated initially with Penrose drainage alone, but most eventually underwent laparotomy (group I, 28 of 30 [93%] versus group II, 19 of 21 [91%]; P value, not significant). The combined stomal/wound complication rate was significantly higher in group I (14 of 30 [47%]) versus group II (6 of 21 [29%]; P <.025). Of 51 patients, one operation was required in 23 (45%), 2 in 18 (35%), 3 in 8 (16%), and 4 in 2 (4%).

CONCLUSIONS

Although the stomal/wound complication rate was significantly higher in group I, both groups had very substantial complication rates, emphasizing the vulnerability of this infant population. Parents, especially of very premature babies, should be advised that multiple operations are likely and that complications should be expected.

Usefulness of surveillance cultures in neonatal extracorporeal membrane oxygenation

Sepsis is difficult to identify in patients treated with extracorporeal membrane oxygenation (ECMO). This study evaluates the usefulness of surveillance cultures obtained during ECMO. We retrospectively reviewed the records of 187 patients from four ECMO centers with birth weights 1,574 to 4,900 gm and gestational ages 33-43 weeks, over a 4 year interval. Most patients had surveillance blood cultures daily, and tracheal aspirates and urine culture every other day. Charts were reviewed for culture results before, during, and for the 7 days after ECMO, and clinical response to the culture results. A total of 2,423 cultures were obtained during 1,487 days of ECMO, of which 155 were positive (6.4%): 13 of 1,370 blood cultures (0.9%), 137 of 850 tracheal aspirate cultures (16%), and 5 of 203 urine cultures (2.3%). After 72 hours, tracheal aspirate cultures became positive with nosocomial organisms in 33 of 131 patients. None of 153 bacterial urine cultures were positive, and only one of 34 viral urine cultures were positive (CMV). We conclude that routine daily blood cultures are not useful in neonatal ECMO. Tracheal aspirate cultures may be helpful in the management of antibiotic therapy in patients on ECMO for more than 5 days. Routine bacterial urine cultures did not provide useful information.

The role of surgery in children with neurofibromatosis

BACKGROUND/PURPOSE

Neurofibromatosis frequently is complicated by the development of symptomatic lesions such as optic gliomas and plexiform neurofibromas that require operative resection. Although characteristically benign, these neoplasms have often devastating functional and cosmetic effects and must be monitored for malignant transformation. The purpose of this study is to identify and describe the surgical considerations in the care of children with neurofibromatosis.

METHODS

The authors reviewed the charts of all children (<21) at our institution with neurofibromatosis who underwent an operative procedure from 1979 to 1999. Patient demographics, symptomatic lesions, malignant transformation, form of surgical intervention, type of anesthesia, and outcome were collected.

RESULTS

A total of 249 patients with either neurofibromatosis 1 or 2 were identified. Of these, 50 (20%) underwent a total of 93 operations. The average age at operation was 9.4 years (1.2 to 21 years). There were 40 soft tissue procedures, 21 intracranial, and 32 miscellaneous. The soft tissue masses typically were treated with wide local excision, and in 8 of these procedures multiple resections were performed. Fourteen of the 50 patients had malignancies. Five of the tumors were soft tissue sarcomas, and 9 were intracranial malignancies. Three patients died, 2 from malignancy and 1 from acute, obstructive hydrocephalus after operation. There were 3 patients alive with malignancy and 8 others living with varying levels of disability.

CONCLUSIONS

Neurofibromatosis in the pediatric patient frequently requires surgical intervention, often because of symptoms such as pain or cosmetic deformity, or for malignancy. Children should be watched carefully for signs of malignant transformation and undergo biopsy for neurofibromas that exhibit rapid growth. Management of sarcomas should be aggressive with consideration given to re-excision, placement of brachytherapy catheters, metastectomy, and limb salvage with adjuvant therapy when possible. Preoperatively, children should receive clinical and radiographic (computed tomography or magnetic resonance imaging) evaluation for hydrocephalus.

Lymphatic mapping with sentinel node biopsy in pediatric patients

BACKGROUND/PURPOSE

Lymphatic mapping with sentinel node biopsy is used widely in adult melanoma and breast cancer to determine nodal status without the morbidity associated with elective lymph node dissection. This technique can be used in children to determine lymph node status with limited dissection and accurate interpretation. The authors report their initial experience.

METHODS

The charts of patients who underwent lymphatic mapping with sentinel node biopsy were reviewed retrospectively. Lymphoscintigraphy was performed in patients with truncal lesions 24 hours before surgery to determine the draining nodal basin (for surgical mapping). The tumors were injected 1 hour preoperatively with technetium sulfur colloid and in the operating room with Lymphazurin blue. The draining basin was examined using a radioisotope detector. The blue nodes with high counts were localized and removed. If nodal metastases were identified, lymph node dissection was recommended. Four patients were injected only with Lymphazurin blue.

RESULTS

Thirteen children (7 girls, 6 boys; mean age, 7 years) underwent lymphatic mapping with sentinel node biopsy. The tumor types were as follows: 8 malignant melanoma (6 extremity, 2 truncal), 1 malignant peripheral nerve sheath tumor, 1 alveolar soft part sarcoma, and 3 rhabdomyosarcoma. A mean of 2.4 nodes (range, 1 to 6) were removed from each patient. Six patients had a positive sentinel node. Formal lymph node dissection was performed on 4 of the 6 patients, 1 of whom had further nodal disease with 2 of 13 nodes containing micrometastases. One of the 6 patients refused lymph node dissection and adjuvant therapy; the final patient had rhabdomyosarcoma, a malignancy for which lymph node dissection is not indicated. Pulmonary metastasis developed 26 months after diagnoses in the patient with alveolar soft part sarcoma and a negative sentinel node. This patient was injected only with Lymphazurin blue at the time of sentinel node biopsy and refused adjuvant therapy. There have been no other recurrences. There were no complications related to lymphatic mapping or sentinel node biopsy.

CONCLUSIONS

Lymphatic mapping with sentinel node biopsy, using both technetium-labeled sulfur colloid and Lymphazurin blue, can be performed safely in pediatric skin and soft tissue malignancies. Further study with long-term follow-up will determine the utility and accuracy of this technique in pediatric malignancies.

The role of anti-tumor necrosis factor-alpha and interleukin-10 in protecting murine neonates from Escherichia coli sepsis

BACKGROUND/PURPOSE

The neonate is at much higher risk for septic complications and death than the adult. Although some aspects of the infant's immune response are immature, others are fully functional. Many models of septic death are caused by an overexpression of proinflammatory cytokines. If there were inadequate down regulatory mechanisms, this could lead to an overexpression of proinflammatory cytokines. The authors hypothesized that the high mortality rate of the newborn was caused by overexpression of tumor necrosis factor (TNF-alpha) and that interleukin-10 (IL-10) would attenuate this response. The aim of this study was to determine if TNF-alpha plays an important role in early death from Escherichia coli sepsis in the newborn animal and if blocking TNF improves survival.

METHODS

A dose response curve was determined for 1 day old C3H/HEN mice using 10(5) intraperitoneal E coli resulting in a 30% to 50% mortality rate. Litters of newborn (1 day old) C3H/HEN mice received a subcutaneous injection of either 25 or 50 ng of murine IL-10 or 20 microL of anti-TNF-alpha 4 hours before a bacterial challenge. Control animals received nothing. Animals were observed for 5 to 7 days. At least 6 litters (18 pups per group) were used for each regimen.

RESULTS

Anti-TNF-alpha resulted in a significant improvement in survival rate compared with controls (100% v 53%, P < .001). In separate experiments, IL-10 at a dose of 25 ng failed to produce any improvement in survival; however, a 50-ng dose resulted in a significant improvement in treated animals compared with controls (95% v 65%, P < .01).

CONCLUSIONS

TNF-alpha plays an important role in neonatal sepsis, suggesting that the newborn mouse is capable of mounting a significant proinflammatory response to gram-negative bacteria. Newborn mice may respond to bacterial challenge with an overexpression of proinflammatory cytokines or an underproduction of downregulating cytokines. Future attempts at immunomodulation in human infants must be undertaken with caution until the inflammatory response is better defined.

Emergent abdominal decompression with patch abdominoplasty in the pediatric patient

BACKGROUND/PURPOSE

Abdominal compartment syndrome (ACS) is the cardiac, pulmonary, and renal dysfunction that occurs as a result of elevated intraabdominal pressure. The authors present their experience with patch abdominoplasty (PA) in pediatric patients as a means to treat and prevent ACS.

METHODS

The charts of patients who underwent PA were reviewed retrospectively. ACS was defined as the increased oxygen requirements and elevation of peak inspiratory pressures (PIP) associated with abdominal distension and worsening renal and or cardiac function.

RESULTS

A total of 23 patients (13 boys) were treated (average age, 23 months). Diagnoses included necrotizing enterocolitis (NEC, n = 13), trauma (n = 3), Hirschsprung's enterocolitis (n = 2), perforated bowel (n = 4), and bilateral Wilms' tumor with bowel obstruction (n = 1). Oxygen requirements decreased after patch abdominoplasty (mean preoperative FIO2, 0.87 +/- 24, mean postoperative, 0.67 +/- 24 [P = .01]). The PIP decreased significantly in the 13 patients who survived (mean preoperative PIP, 33 +/- 8, mean postoperative PIP, 27 +/- 7 [P = .01]). These PIPs failed to respond in the 8 nonsurvivors (mean preoperative PIP, 35 +/- 10, mean postoperative PIP, 33 +/- 14 [P value not significant]). Six of the 8 nonsurvivors had NEC. Complications of intraabdominal abscess and enterocutaneous fistula were seen in 5 patients, all of who had NEC.

CONCLUSIONS

Patch abdominoplasty effectively decreases airway pressures and oxygen requirements associated with ACS. Complications with PA occur primarily in patients with NEC. Failure to respond with a decrease in PIP and FIO2 requirements is an ominous sign.

Late versus early surgical correction for congenital diaphragmatic hernia in newborn infants

BACKGROUND

Congenital diaphragmatic hernia, although rare (1 per 2-4,000 births), is associated with high mortality and cost. Opinion regarding the timing of surgical repair has gradually shifted from emergent repair to a policy of stabilization using a variety of ventilatory strategies prior to operation. Whether delayed surgery is beneficial remains controversial.

OBJECTIVES

To summarize the available data regarding whether surgical repair in the first 24 hours after birth rather than later than 24 hours of age improves survival to hospital discharge in infants with congenital diaphragmatic hernia who are symptomatic at or immediately after birth.

SEARCH STRATEGY

Search of Medline (1966-1999), Embase (1978-1999) and the Cochrane databases using the terms "congenital diaphragmatic hernia" and "surg*"; citations search, and contact with experts in the field to locate other published and unpublished studies.

SELECTION CRITERIA

Studies were eligible for inclusion if they were randomized or quasi-randomized trials that addressed infants with CDH who were symptomatic at or shortly after birth, comparing early (<24 hours) vs late (>24 hours) surgical intervention, and evaluated mortality as the primary outcome.

DATA COLLECTION AND ANALYSIS

Data were collected regarding study methods and outcomes including mortality, need for ECMO and duration of ventilation, both from the study reports and from personal communication with investigators. Analysis was performed in accordance with the standards of the Cochrane Neonatal Review Group.

MAIN RESULTS

Two trials met the pre-specified inclusion criteria for this review. Both were small trials (total n<90) and neither showed any significant difference between groups in mortality. Meta-analysis was not performed because of significant clinical heterogeneity between the trials.

REVIEWER'S CONCLUSIONS

There is no clear support for either immediate (within 24 hours of birth) or delayed (until stabilized) repair of congenital diaphragmatic hernia, but a substantial advantage to either one cannot be ruled out. A large, multicenter randomized trial would be needed to answer this question.

Effects of dexamethasone on meconium aspiration syndrome in newborn piglets

We examined the effects of dexamethasone on lung function in a piglet model of meconium aspiration syndrome. We induced lung injury in 10 newborn piglets (age 5 +/- 0.2 d) with 4 mL/kg body weight of 20% sterile human meconium in normal saline given via tracheostomy. Ventilator management was aimed at maintaining comparable values of end tidal carbon dioxide, Hb saturation, and arterial blood gases. Lung function was assessed using a BICORE CP100 neonatal monitor. Five piglets received 0.5 mg/kg of dexamethasone 2 and 8 h after meconium administration, whereas control piglets received normal saline at similar times. Ventilator settings, oxygen requirements, and lung compliance were similar between groups at the start of the study. Two hours after the instillation of meconium, there was marked lung dysfunction in both groups as evidenced by increased oxygen requirements [fraction of inspired oxygen (FiO2) 0.98 +/- 0.01 versus FiO2 0.21 +/- 0, p < 0.0001] and reduced lung compliance (0.35 +/- 0.03 versus 0.8 +/- 0.03 mL x kg(-1) x cm(-1) H2O, p < 0.0001). Administration of dexamethasone resulted in lower oxygen requirements (FiO2 0.27 +/- 0.01 versus FiO2 1.0 +/- 0.0, p < 0.00001), lower oxygenation index (2.17 +/- 0.17 versus 22.64 +/- 3.39, p < 0.0001), ventilatory efficiency index (0.30 +/- 0.01 versus 0.07 +/- 0.01, p < 0.0001), and improved lung compliance (0.68 +/- 0.04 versus 0.34 +/- 0.05 mL x kg(-1) x cm(-1) H2O, p < 0.001) compared with the control group. In summary, a two-dose course of 0.5 mg/kg of dexamethasone improved blood gases and lung function in a piglet model of meconium aspiration syndrome.

Evidence-based practice in pediatric surgery

BACKGROUND/PURPOSE

The current medical environment demands the provision of quality healthcare at an affordable cost. Both payors and regulators are committed to lowering cost through initiation of best practice strategies that include practice guidelines, clinical pathways, and standards of care. The only practical way to join this debate is through the use of objective, unbiased clinical data. This study was undertaken to review the current state of the pediatric surgery literature and its value in determining best clinical practice.

METHODS

The National Library of Medicine Medline database was accessed using the Ovid Internet client software. All references, abstracts, and keyword indexes from the core pediatric surgery literature, the Journal of Pediatric Surgery, the European Journal of Pediatric Surgery, Pediatric Surgery International, Zeitschrift fur Kinderchirurgie, and Seminars in Pediatric Surgery were downloaded and reviewed. Search criteria were defined to identify prospective, randomized, controlled studies. References were then categorized as case reports; retrospective case series; prospective case series; randomized, controlled studies; laboratory studies; review articles; or miscellaneous studies.

RESULTS

As of March 1, 1998, there are 9,373 references, excluding citations of letters or comments, contained in the core pediatric surgery literature, as provided through Medline. Of these, 485 were identified as studies for review, possible prospective case series or prospective, randomized, controlled studies. After review, 34 studies (0.3%) were classified as prospective, randomized, controlled studies, whereas 139 (1.48%) were classified as prospective studies. There were 3,241 (34.6%) case reports, 5,619 (59.9%) retrospective case series, 1,109 (11.8%) laboratory studies, 195 (2.1%) review articles, and 36 (0.3%) miscellaneous studies that did not fit into other categories. When analyzed by decade of publication, prospective studies and prospective, randomized, controlled studies (n = 173) numbered 103 in the 1990s, 63 in the 1980s, and seven in the 1970s.

CONCLUSIONS

There is a paucity of scientifically rigorous data on which to base clinical practice in pediatric surgery. The increasing numbers of prospective, case-controlled studies or the more sound prospective, randomized, controlled trials in the 1990s suggests that pediatric surgeons are aware of the need to generate unbiased data to support current clinical practice and the development of practice guidelines. Limitations exist in conducting prospective, randomized, controlled trials because of the rare nature of many pediatric surgical conditions and the lack of clinical "equipoise" over available treatment options. The authors encourage the use of multiinstitutional trials and the prospective, randomized, controlled study methodology to develop data that can be used to guide clinical practice in our evolving healthcare environment.

Meconium stimulates a pro-inflammatory response in peritoneal macrophages: implications for meconium peritonitis

BACKGROUND/PURPOSE

Although meconium peritonitis is a rare condition, the mortality rate can be as high as 40%. Meconium peritonitis is a result of intestinal perforation in utero, which leads to dense inflammation in the peritoneal cavity. The fetus has relatively immature peritoneal defense mechanisms, so the cause of this dense inflammation is unclear. The peritoneal macrophage is a key cell in the peritoneal inflammatory response in adults. The purpose of this investigation was to determine if sterile meconium had a direct stimulatory effect on the peritoneal macrophage.

METHODS

Peritoneal macrophages were harvested from adult C3H/HEN mice. The cells were placed in microtiter wells at 10(5) cells per well. Sterile human meconium was diluted in media and placed in the wells at varying concentrations for 8 hours. Lipopolysaccharide (LPS) (10 microg/mL) served as a positive control. Supernatants were harvested and assayed for tumor necrosis factor alpha (TNF-alpha) using a commercial ELISA kit. Separate cells were assayed for TNF-alpha message using polymerase chain reaction (PCR). In another series of experiments, procoagulant activity (PCA) was determined on freeze-thawed cells using a two-stage amidolytic assay. To test for the role of protein kinase C (PKC) in the PCA response H7, a PKC inhibitor, was used as well.

RESULTS

Meconium stimulation resulted in a significant increase in TNF-alpha compared with negative controls with a peak at 0.1% meconium (121 pg/mL v 11 pg/mL, P<.05). There was a significant increase in PCA, with a 10-fold increase with 1% meconium compared with controls (P<.05). This response was limited to less than 5% by PKC inhibition.

CONCLUSIONS

Sterile meconium results in a marked proinflammatory response in the peritoneal macrophage with elevations of both PCA and TNF-alpha. The TNF response is likely mediated at a pretranscriptional level because there is a marked increase in TNF mRNA. These data suggest that the PCA response is regulated by a PKC mechanism similar to LPS. Stimulation of the peritoneal macrophage by meconium is a possible cause of the marked inflammation seen in meconium peritonitis.

A multicenter trial of 6-aminocaproic acid (Amicar) in the prevention of bleeding in infants on ECMO

BACKGROUND/PURPOSE

Intracranial hemorrhage (ICH), is a major source of morbidity and the leading cause of death in neonates treated with extracorporeal membrane oxygenation (ECMO). Anecdotal reports have suggested that epsilon-aminocaproic acid (EACA) can decrease the risk of ICH. The purpose of this study was to evaluate, in a multiinstitutional, prospective, randomized, blinded fashion, the effect of EACA on the incidence of hemorrhagic complications in neonates receiving ECMO.

METHODS

All neonates (except congenital diaphragmatic hernia) who met criteria for ECMO at three institutions were eligible for enrollment. EACA (100 mg/kg) or placebo was given at the time of cannulation followed by 25 mg/kg/h for 72 hours. Bleeding complications, transfusion requirements, and thrombotic complications were recorded. Post-ECMO imaging included head ultrasound scan computed tomography (CT) scan, and duplex ultrasound scan of the inferior vena cava and renal vessels.

RESULTS

Twenty-nine neonates were enrolled (EACA, 13 and placebo, 16). Five (17.2%) patients had a significant (grade 3 or larger) ICH. There was no statistical difference in the incidence of significant ICH in patients who received EACA (23%) versus placebo (12.5%). Septic patients accounted for all of the ICH in the EACA group. Thrombotic complications (aortic thrombus and SVC syndrome) developed in two patients from the placebo group. There was no difference in thrombotic circuit complications between groups.

CONCLUSIONS

Our results suggest that the use of EACA in neonates receiving ECMO is safe but may not decrease the overall incidence of hemorrhagic complications.

Utility of daily head ultrasonography for infants on extracorporeal membrane oxygenation

BACKGROUND/PURPOSE

Intracranial hemorrhage (ICH) is a major concern during extracorporeal membrane oxygenation (ECMO). Daily cranial ultrasonography has been used by many ECMO centers as a diagnostic tool for both detecting and following ICH while infants are on bypass. The purpose of this patient review was to look at the usefulness of performing daily cranial ultrasonography (HUS) in infants on ECMO in detecting intraventricular hemorrhage of a magnitude sufficient to alter patient treatment.

METHODS

The authors reviewed retrospectively all of the records of all neonates treated with ECMO at the Hermann Children's Hospital, Wilford Hall USAF Medical Center, Cincinnati Children's Hospital, The University of Texas Medical Branch at Galveston, and Texas Children's Hospital between February 1986 to March 1995. Two hundred ninety-eight patients were placed on ECMO during this period. All patients had HUS before, and daily while on ECMO, and all were reviewed by the staff radiologists. A total of 2,518 HUS examinations were performed.

RESULTS

Fifty-two of 298 patients (17.5%) had an intraventricular hemorrhage seen on ultrasound scan. Nine of 52 patients (17.3%) had an ICH seen on the initial HUS examination before ECMO, all of which were grade I, and 43 of 52 patients (82.7%) had ICH while on ECMO. Of these ICH, 15 were grade I, 10 were grade II, 10 were grade III, and eight were grade IV. Forty of these ICH (93%) were diagnosed by HUS during the first 5 days of the ECMO course. Seven hundred eighty-six HUS were performed after day 5, at an estimated cost of $300,000 to $450,000 (charges), demonstrating three new intraventricular hemorrhages, one grade I, and one grade IV on day 7 and one grade I on day 8. Eight patients were taken off ECMO because of ICH diagnosed within the first 5 days. One patient was taken off ECMO because of ICH diagnosed after 5 days. This patient had clinical symptoms suggestive of ICH.

CONCLUSIONS

Almost all ICH occur during the first 5 days of an ECMO course. Unless there is a clinical suspicion, it is not cost effective to perform HUS after the fifth day on ECMO, because subsequent HUS examinations are unlikely to yield information significant enough to alter management.

Current surgical management of congenital diaphragmatic hernia: a report from the Congenital Diaphragmatic Hernia Study Group

BACKGROUND

Repair of congenital diaphragmatic hernia (CDH) has changed from an emergent procedure to a delayed procedure in the last decade. Many other aspects of management have also evolved since the first successful repair. However, most reports are from single institutions. The lack of a large multicenter database has hampered progress in the management of congenital diaphragmatic hernia (CDH) and makes determination of the current standard difficult.

METHODS

The CDH study group was formed in 1995 to collect data from multiple institutions in North America, Europe, and Australia. Participating centers completed a registry form on all live-born infants with CDH during 1995 and 1996. Demographic information, data about surgical management, and outcome were collected for all patients.

RESULTS

Sixty-two centers participated, with 461 patients entered. Overall survival was 280 of 442 patients (63%) where survival was recorded. The defect was left-sided in 78%, right-sided in 21%, and bilateral in 1%. A subcostal approach was used in 91% of patients, with pleural drainage used in 76%. A patch of some kind was used in just over half (51%) of the patients, with polytetrafluoroethylene being the most commonly used material (81%) in those patients with a patch. The mean surgical time was 102 minutes, with an average blood loss of 14 mL (range, 0 to 500 mL). The overwhelming majority of patients underwent repair between 6:00 AM and 6:00 PM (289 of 329, 88%). Nineteen percent of patients had surgical repair on extracorporeal membrane oxygenation (ECMO) at a mean time of 170 hours into the ECMO course (range, 10 to 593 hours). The mean age at surgery in patients not treated with ECMO was 73 hours (range, 1 to 445 hours).

CONCLUSIONS

The multicenter nature of this report makes it a snapshot of current management. The data would indicate that prosthetic patching of the defect has become common, that after-hours repair is infrequent, and that delayed surgical repair has become the preferred approach in many centers. Furthermore, the mean survival rate of 63% indicates that despite decades of individual effort, the CDH problem is far from solved. This highlights the need for a centralized database and cooperative multicenter studies in the future.

Postoperative respiratory complications in ex-premature infants after inguinal herniorrhaphy

BACKGROUND/PURPOSE

The duration of postoperative cardiorespiratory monitoring of premature infants after inguinal herniorrhaphy is uncertain. Prolonged observation requiring hospital admission may be unnecessary and increases costs.

METHODS

This study was a retrospective review of 191 inguinal herniorrhaphies performed between 1993 and 1996 at the Hermann Children's Hospital. The authors reviewed their experience to identify factors associated with postoperative apnea and bradycardia and determine a safe period of observation.

RESULTS

Among 191 elective inguinal herniorrhaphies performed, 57 (29.8%) were in expremature infants (< or =60 weeks postconception). Five (8.8%) infants either failed extubation or were unable to extubate (group 1). The average age for this group was 41.0 +/- 1.2 weeks compared with 47.2 +/- 1.0 (P = .06) for those who were successfully extubated (group II). Preoperative apnea-bradycardia was found in four (80%) infants in group I compared with 32 (61.5%) in group II (P = 0.67). All group I and 21 (40.4%, P = .09) group II infants with a history of preoperative apnea required intubation for an average of 24.4 +/- 7.8 days and 8.2 +/- 2.4 days, respectively (P = .04). American Society of Anesthesia (ASA) scores were 2.6 +/- 0.4 for group I compared with 1.8 +/- 0.1 for group 11 (P = .01). The use of both intraoperative narcotics (three [60%] in group I v six [12%] in group II, P = .01]) and vecuronium (four [80%] in group I v 16 [31%] in group II, P = .03) were significantly more common in group I infants. Operating room time was 46.4 +/- 4.1 minutes for group I compared with 60.6 +/- 3.9 minutes for group II (P = .27). Postoperative apnea-bradycardia occurred in all five group I infants and two (3.8%, P = .001) group II infants. Group II infants were treated successfully with supplemental oxygen.

CONCLUSIONS

All instances of postoperative apnea-bradycardia and laryngospasm occurred within 4 hours after operation without significant differences between groups. The risk of postoperative cardiorespiratory distress requiring reintubation in premature infants who undergo inguinal herniorrhaphy is not insignificant (8.8%). The judicious use of narcotics and vecuronium, and limiting patient selection to those with ASA score of less than 3 may lessen the need for reintubation. When present cardiorespiratory distress occurs early; therefore we recommend outpatient inguinal herniorrhaphy as a safe and cost-effective choice.

Pediatric wound infections: a prospective multicenter study

OBJECTIVE

Surgical wound infections remain a significant source of postoperative morbidity. This study was undertaken to determine prospectively the incidence of postoperative wound infections in children in a multi-institutional fashion and to identify the risk factors associated with the development of a wound infection in this population.

SUMMARY BACKGROUND DATA

Despite a large body of literature in adults, there have been only two reports from North America concerning postoperative wound infections in children.

METHODS

All infants and children undergoing operation on the pediatric surgical services of three institutions during a 17-month period were prospectively followed for 30 days after surgery for the development of a wound infection.

RESULTS

A total of 846 of 1021 patients were followed for 30 days. The overall incidence of wound infection was 4.4%. Factors found to be significantly associated with a postoperative wound infection were the amount of contamination at operation (p = 0.006) and the duration of the operation (p = 0.03). Comparing children who developed a wound infection with those who did not, there were no significant differences in age, sex, American Society of Anesthesiologists (ASA) preoperative assessment score, length of preoperative hospitalization, location of operation (intensive care unit vs. operating room), presence of a coexisting disease or remote infection, or the use of perioperative antibiotics.

CONCLUSIONS

Our results suggest that wound infections in children are related more to the factors at operation than to the overall physiologic status. Procedures can be performed in the intensive care unit without any increase in the incidence of wound infection.

Congenital diaphragmatic hernia survival and use of extracorporeal life support at selected level III nurseries with multimodality support

BACKGROUND

Congenital diaphragmatic hernia (CDH) has been cited to have a mortality rate of 50%. There have been multiple studies at individual institutions demonstrating potential benefits from various strategies including extracorporeal life support (ECLS), delayed repair, and lower levels of ventilator support. There has been no multicenter survey of institutions offering these modalities to describe the current use of ECLS and survival of these infants. In addition, the relationship between the number of patients with CDH managed at an individual institution and outcome has not been evaluated.

METHODS

We queried 16 level III neonatal intensive care centers on the use of ECLS and survival of infants with CDH who were treated during 2 consecutive years (1993 to 1995). Data are presented as mean +/- SEM, median, and range.

RESULTS

Data were collected on 411 patients. Of these, 71% +/- 8% were outborn and 8% +/- 3% were considered nonviable. Overall survival of CDH infants was 69% +/- 4% (range, 39% to 95%). The survival rate of infants on ECLS was 55% +/- 4%, whereas survival of infants not requiring ECLS was significantly increased at 81% +/- 5% (p = 0.005). The mean rate of ECLS use was 46% +/- 2%. There was no correlation between the number of cases per year at an individual institution and overall survival, ECLS survival, or ECLS use (r = 0.341, 0.305, and 0.287, respectively). There was also no correlation between case volume at an individual institution and ECLS survival (r = 0.271).

CONCLUSIONS

The current survival rate and rate of ECLS use in infants with CDH at level III neonatal intensive care units in the United States are 69% +/- 4% and 46% +/- 2%, respectively. There is no correlation between the yearly individual center experience with managing CDH and rate of ECLS use or outcome.

Operative treatment of truncal vascular injuries in children and adolescents

BACKGROUND/PURPOSE

Pediatric truncal vascular injuries are rare, but the reported mortality rate is high (35% to 55%), and similar to that in adults (50% to 65%). This report examines the demographics, mechanisms of injury, associated trauma, and results of treatment of pediatric patients with noniatrogenic truncal vascular injuries.

METHODS

A retrospective review (1986 to 1996) of a pediatric (< or = 17 years old) trauma registry database was undertaken. Truncal vascular injuries included thoracic, abdominal, and neck wounds.

RESULTS

Fifty-four truncal vascular injuries (28 abdominal, 15 thoracic, and 11 neck injuries) occurred in 37 patients (mean age, 14+/-3 years; range, 5 to 17 years); injury mechanism was penetrating in 65%. Concomitant injuries occurred with 100% of abdominal vascular injuries and multiple vascular injuries occurred in 47%. Except for aortic and one SMA injury requiring interposition grafts, these wounds were repaired primarily or by lateral venorrhaphy. Nonvascular complications occurred more frequently in patients with abdominal injuries who were hemodynamically unstable (systolic blood pressure [BPS] <90) on presentation (19 major complications in 11 patients versus one major complication in five patients). Thoracic injuries were primarily blunt rupture or penetrating injury to the thoracic aorta (nine patients). Thoracic aortic injuries were treated without bypass, using interposition grafts. In patients with thoracic aortic injuries, there were no instances of paraplegia related to spinal ischemia (clamp times, 24+/-4 min); paraplegia occurred in two patients with direct cord and aortic injuries. Concomitant injuries occurred with 83% of thoracic injuries and multiple vascular injuries occurred in 25%. All patients with thoracic vascular injuries presenting with BPS of less than 90 died (four patients), and all with BPS 90 or over survived (eight patients). There were 11 neck wounds in 9 patients requiring intervention, and 8 were penetrating. Overall survival was 81%; survival from abdominal vascular injuries was 94%, thoracic injuries 66%, and neck injuries 78%.

CONCLUSIONS

Survival and subsequent complications are related primarily to hemodynamic status at the time of presentation, and not to body cavity or vessel injured. Primary anastomosis or repair is applicable to most nonaortic wounds. The mortality rate in pediatric abdominal vascular injuries may be lower than previously reported.

Should laparoscopic appendectomy be avoided for complicated appendicitis in children?

BACKGROUND/PURPOSE

Laparoscopic appendectomy is becoming the preferred technique for treating acute appendicitis. However, recent literature on adults suggests that laparoscopic appendectomy may increase the risk for postoperative infectious complications in complicated (gangrenous or perforated) cases. This study was undertaken to compare the results of open versus laparoscopic appendectomy for complicated appendicitis in children.

METHODS

A retrospective review from two institutions was performed for all children treated operatively for complicated appendicitis from January 1994 through November 1996.

RESULTS

Fifty-six cases were identified. Twenty-seven children underwent laparoscopic appendectomy, whereas 22 underwent open appendectomy. Seven children underwent conversion from laparoscopic to open surgery. Operating times and length of hospital stay did not differ significantly between the laparoscopic and open groups. Postoperative complications developed in 24 children (42.8%). Complications were more frequent after laparoscopic appendectomy compared with open appendectomy (56% v 18%, P = .002). A postoperative intraabdominal abscess (IAA) developed in 14 children (25%). An IAA occurred in two children after open appendectomy compared with 11 children after laparoscopic appendectomy (9% v 41%, P = .01).

CONCLUSION

The findings suggest that laparoscopic appendectomy should be avoided in children who have complicated appendicitis because of the increased risk for postoperative intraabdominal abscesses. The authors propose a prospective, randomized trial to verify this finding.

Importance of diarrhea as a presenting symptom of appendicitis in very young children

BACKGROUND

Appendicitis is an uncommon diagnosis in very young children. It is frequently complicated by delays in diagnosis, perforation, and lengthy hospital stays.

OBJECTIVES

To review our recent experience with appendicitis among children younger than 3 years old, and to identify the independent predictors of a prolonged hospital stay.

METHODS

A retrospective case series review was performed on all children under age 3 who had an appendectomy for appendicitis between January 1983 and February 1994. Multiple regression analysis was used to identify the independent predictors of a prolonged hospital stay.

RESULTS

Sixty-three children were identified. Mean age was 2.2 years (range 11 to 35 months). The mean delay from onset of symptoms to presentation was 4.3 days. Fifty-seven percent were initially misdiagnosed. Diarrhea was reported in 33%. Perforation and/or gangrene were found in 84%. Perforation and/or gangrene at laparotomy and a history of diarrhea at presentation were independent predictors of a prolonged hospital stay.

CONCLUSIONS

Appendicitis in children under 3 years old is characterized by delays in diagnosis and perforation. A history of diarrhea is an important factor that confuses the diagnosis, prolongs the observation period, and delays appropriate therapy.

Second malignant neoplasms in children after treatment of soft tissue sarcoma

Currently, approximately 67% of children diagnosed with cancer can be expected to survive more than 5 years. Among the most significant late effects of cancer therapy is the development of second malignant neoplasm (SMN). This study was performed to identify the factors associated with the development of second malignant neoplasms after treatment for soft tissue sarcomas in childhood. Retrospectively the charts of 20 children who developed second malignant neoplasms after treatment for primary childhood soft tissue sarcoma were reviewed. Presentation, age at diagnosis, tumor histology, extent of tumor, treatment, family histories (when available), and outcome were recorded. The mean age of the patients (10 boys, 10 girls) was 8.5 years of age (range, 1 to 20 years). Most primary tumors were rhabdomyosarcoma (14/20) and occurred in an extremity (10/20). Ninety percent of the patients (18/20) had a complete response to treatment of the primary cancer. Eleven out of 20 received combined chemotherapy and radiation therapy. The most common secondary malignancy was a bone sarcoma (6/20), followed by brain tumors (n = 3), leukemia (n = 2), and other sarcomas (n = 2). Four of the bone sarcomas developed in the field of radiation treatment. Median follow-up was 16 years (range, 1 to 26 years). The median time to development of a SMN was 11.4 years (range, 1.5 to 21 years). Survival after a second malignancy was only 30%. Two patients developed a third malignant neoplasm. The occurrence of a secondary malignancy represents a serious complication of childhood cancer. Certain tumors are related directly to treatment such as osteosarcoma within irradiated fields and secondary leukemias or lymphomas after certain chemotherapy regimens. Combined radiotherapy and chemotherapy may play an additive role in the development of second malignant neoplasms. Genetic factors may predispose affected patients to the development of both primary and secondary malignancies. Close surveillance of children previously treated for childhood cancers is warranted.

Melanoma as a second malignant neoplasm after childhood cancer

BACKGROUND

As more children survive childhood cancers, the population at risk for second malignant tumors increases. The development of melanoma as a second malignant tumor is not well described.

METHODS

The M.D. Anderson Cancer Center's 50-year experience with patients who developed melanoma after treatment of a childhood cancer was retrospectively reviewed.

RESULTS

One hundred seventy-two patients with a second malignancy were identified; 11 patients had melanoma as a second malignancy. The most common first malignancies were Hodgkin's disease, brain tumors, and retinoblastomas. Melanoma developed in an irradiated field in 4 patients. Six patients had lymphatic or distant metastasis at diagnosis. Five of 11 patients died of melanoma.

CONCLUSIONS

Factors contributing to melanoma as a second malignancy may include genetic factors and the effects of chemotherapy and radiation. Survivors of childhood malignancy should be considered at risk for developing melanoma, and suspicious pigmented lesions should be carefully evaluated.

Extracorporeal membrane oxygenation in patients with congenital diaphragmatic hernia

Since the introduction of extracorporeal membrane oxygenation (ECMO) support for neonatal respiratory failure, the use of ECMO for infants with congenital diaphragmatic hernia has increased significantly. ECMO is offered to infants with a high risk of dying (with reported survival rates of 38% to 65%). Unstable infants can be placed on ECMO with subsequent repair on ECMO or after weaning from support. The complication rate can be high with repair on ECMO, but changes in operative techniques have decreased the risk. Most centers use venoarterial ECMO in patients with congenital diaphragmatic hernia (CDH), but venovenous ECMO appears as effective. ECMO support appears to have improved the survival rate in high-risk infants with CDH, but because almost all studies are retrospective single institutional and have small numbers of patients, the true improvement in survival rate is difficult to quantitate. Further studies of the value of ECMO in patients with CDH are warranted.

Malignant fibrous histiocytoma in children

Because malignant fibrous histiocytoma (MFH) rarely occurs in children, the natural history of this tumor and prognostic factors predictive of outcome have not been well described. The charts of all pediatric patients with MFH seen at M.D. Anderson Cancer Center were reviewed with respect presentation, treatment, and outcome, in an attempt to determine prognostic factors that are predictive of survival. Forty-four pediatric patients were identified. Extremities were the most common tumor site (31 of 44 patients). Five patients presented with angiomatoid histology subtype; all subsequently survived. The estimated 5-year survival rate was 85% for clinical group I patients, 87% for clinical group II, 53% for clinical group III, and 0% for clinical group IV. The estimated 5-year survival rate was 95% for patients with tumors of less than 5 cm in diameter and 45% for those with larger tumors. Overall, the estimated 5-year survival rate was 71%. Significant prognostic factors found to affect survival (by univariate analysis) were clinical group, tumor size, and recurrence. Gender and race were not significant predictors. The use of chemotherapy and radiation was not found to improve the chance of survival, but this most likely reflected the more frequent use of adjuvant therapy in patients with unresectable or high-grade tumors. Although adequate surgical resection continues to be the most effective treatment, investigation of adjuvant chemotherapy and radiation therapy on protocol is warranted.

Evaluation of a new thin-walled endotracheal tube for use in children

Conventional endotracheal tubes have high intrinsic resistive properties due to their high outer-to-inner diameter ratio. This has significant disadvantages in the treatment of the small neonatal or pediatric patient as work of breathing increases with decreasing internal radius. Diagnostic and therapeutic procedures, including suctioning, may be very difficult in patients with small endotracheal tubes. We therefore measured airway resistance and pressure differential during simulated mechanical ventilation using proximal and distal endotracheal tube flow transducers. Conventional and new, ultrathin-walled endotracheal tubes reinforced with flat stainless steel or a novel, crush-proof nickel-titanium alloy were compared using fixed ventilator settings. Ventilation through the ultrathin-walled tubes resulted in a significantly reduced airway resistance (p < or = 0.01). These new ultrathin-walled endotracheal tubes showed flow characteristics typical of much larger conventional endotracheal tubes: the 3.2-mm internal diameter had an airway resistance (Raw) of 36, while a standard 2.5-mm internal diameter endotracheal tube had a Raw of 146. Both endotracheal tubes have identical external diameters of 3.6 mm. We conclude that ultrathin-walled endotracheal tubes could have a significant role in the treatment of the ventilated child by facilitating interactive ventilation and maintenance of airway patency and may make procedures such as fiberoptic endoscopy and intrapulmonary ventilation using reverse-thrust catheters possible in the small child.

Supraumbilical skin-fold incision for pyloromyotomy

We describe our experience with a supraumbilical skin-fold incision for pyloromyotomy in infants. Our technique uses a vertical fascial incision. This approach provides excellent exposure to the pylorus, allows greater operative flexibility, and results in a superior cosmetic outcome compared to the traditional right upper-quadrant incision.

Intratracheal pulmonary ventilation provides effective ventilation in a near-drowning model

Overdistension of the lungs from high inspiratory pressure is increasingly recognized as a major contributor to lung injury and worsening respiratory failure in the child who requires prolonged mechanical ventilation. Many modes of ventilation (such as high-frequency ventilation) have been introduced in an attempt to decrease this lung injury. Recently, a new mode of tracheal ventilation, intratracheal pulmonary ventilation (ITPV), has been described. By using a catheter positioned at the carina with continuous gas flow, it is possible to achieve effective ventilation at very low pressures. The purpose of this study was to evaluate the usefulness of ITPV in a near-drowning model. Ten domestic Yorkshire swine underwent arterial, venous, and pulmonary arterial catheter as well as tracheotomy placement. All animals received 13 mL/kg of fresh water intratracheally to induce a pulmonary injury. Six pigs were ventilated for 4 hours using ITPV; the other four pigs received conventional mechanical ventilation (CMV). Circulatory and ventilatory pressures, hemodynamic variables, arterial blood gases, and end-tidal CO2 were measured before lung injury and every 30 minutes thereafter. Both proximal and distal peak and mean airway pressures were measured. The animals were ventilated as needed to maintain the arterial blood gases in the normal range. The authors found the expected changes in pulmonary compliance, oxygen requirement, and airway pressure after inducement of lung injury. The six animals treated with ITPV had significantly lower airway pressures than those of controls. Peak inspiratory pressures with ITPV were 8.2 +/- 1.9 cm H2O versus 17.8 +/- 3.7 with CMV (P < .001). Distal mean airway pressures using ITPV were 2.3 +/- 0.1 cm H2O versus 9.0 +/- 3.2 with CMV (P < .01). With respect to hemodynamic variables, there were no differences between experimental and control animals. In conclusion, ITPV can afford effective ventilation in a near-drowning model of lung injury at airway pressures significantly lower than those required with CMV. ITPV could be a very valuable addition to the currently available methods of mechanical ventilation.

Age-dependent susceptibility to intraabdominal abscess formation

Infection remains a major cause of morbidity and mortality in the surgical neonate, with the risk of developing infectious complications decreasing as age increases. Developmental changes in the immune system, as well as transplacentally acquired immunity, likely play a role in this differential risk. The purpose of this study was to determine whether there is an age-related susceptibility to intraabdominal abscess formation. The authors used a mouse model in which the combination of an aerobe, anaerobe, and adjuvant routinely forms abscesses. Litters of at least six C57 BL/6 mice were used. The mice received 10(7) of Enterococcus faecalis and 10(7) Bacteroides distasonis or 10(7) B distasonis alone. The mice were given 8 microL/g of 50% wheat bran (40 mg/mL) and 50% bacteria. There were at least four litters for each experiment. Intraabdominal abscesses were counted after 7 days. Ten-day-old mice had an incidence of intraabdominal abscesses that was similar to that of the adults (81% v 91%). There was a significant decrease in intraperitoneal infection after 10 days, until weaning (37% and 38%; P < .05). The authors conclude that there are significant developmental changes in susceptibility to intraabdominal abscess formation, which may reflect changes in peritoneal defense mechanisms.

Bronchogenic and esophageal duplication cyst in a single mediastinal mass in a child

We report an unusual case of a mediastinal foregut malformation consisting of complete components of both a bronchogenic and an esophageal duplication cyst in a child. The lesion was identified as an incidental finding during evaluation of a clavicular fracture. Thoracotomy was performed for excision of the mass. A discussion of the pathological findings and the diagnosis and management of foregut malformations is presented.

A half century of experience with carcinoid tumors in children

PURPOSE

To investigate the frequency, presentation, clinical management, and prognosis of appendiceal carcinoid tumors in children.

METHOD

A review of our institution's experience over 50 years.

RESULTS

Twenty-two patients below the age of 20 presented with appendiceal carcinoid tumor. The mean age at presentation was 14.6 years. Twelve patients presented with symptoms of appendicitis. No tumor was > 2.0 cm in size. Only 2 patients underwent resection beyond appendectomy. No patient had recurrent or metastatic carcinoid tumor, and all but 1 patient (who died of ovarian choriocarcinoma) are alive without evidence of carcinoid tumors 1.5 to 30 years after diagnosis.

CONCLUSIONS

Appendiceal carcinoid tumors in children are rarely life-threatening and the incidence of large tumors (> 2.0 cm) is very low. The role of right hemicolectomy in large (> 2.0 cm) tumors is questionable in this age group.

Venovenous bypass as an adjunct for the management of a retrohepatic venous injury in a child

We report the successful utilization of venovenous bypass in the case of an 8-year-old-boy who suffered a major hepatic injury with a retrohepatic venous injury after a kick by a horse. Initial nonoperative management was successful, but a delayed hemorrhage required operation. Vascular access was obtained via the peripheral circulation, and venovenous bypass was performed without systemic heparinization. Venovenous bypass improved vascular control and allowed the repairs to be performed in a relatively bloodless field, while not compromising venous return.

Complications after surgical intervention for necrotizing enterocolitis: a multicenter review

Necrotizing enterocolitis (NEC) is a serious condition affecting predominantly the premature infant. The purpose of this study is to report a multicenter experience of complications in 252 infants requiring surgical therapy for NEC. Data from eight institutions for the years 1980 through 1990 were collected and analyzed for infants undergoing surgical therapy for NEC. Records were reviewed for gestational age, birth weight, age at operation, indications for operation, degree of intestinal involvement, operation(s) performed, complications, and 30-day mortality rates. A total of 264 infants underwent surgical intervention for NEC during the study period. Complete information was available for 252 patients. The mean gestational age was 31 +/- 5 weeks and the mean birth weight was 1,552 +/- 823 g. The mean age at operation was 18 +/- 35 days. Pneumoperitoneum was the most common indication for operation (42%). The 30-day survival rate was 72%. Eighty-one percent of patients underwent primary laparotomy, whereas peritoneal drainage was performed in 48 (19%) patients. Postoperative complications were identified in 119 (47%) patients. The most common postoperative complications were sepsis (9%), intestinal strictures (9%), and short gut (9%). Wound infections occurred in 6%, and the incidence of intraabdominal abscess formation was only 2.3%. Gestational age < 27 weeks (P < .005) and birth weight < 1,000 g (P < .005) were associated with significantly increased mortality but no increase in postoperative morbidity. The incidence of complications was similar in the very low birth weight (< 1,000 g) infants (51%) compared with infants > or = 1,000 g (46%).(ABSTRACT TRUNCATED AT 250 WORDS)

Use of extracorporeal membrane oxygenation in the septic neonate

Extracorporeal membrane oxygenation (ECMO) is widely used for cardiopulmonary support in neonates with cardiopulmonary failure secondary to overwhelming sepsis. The purpose of this study was to examine the effects of culture status on the eventual outcome of septic neonates requiring ECMO support. Data from the Extracorporeal Life Support Organization (ELSO) for the tears 1990 through 1992 inclusive were collected and analyzed for all neonates with a primary diagnosis of sepsis. Records were reviewed for gestational age, birth weight, culture status and isolated organism, last arterial blood gas before beginning ECMO, hemorrhagic complications during bypass, and overall survival. Gram-positive sepsis accounted for 85% of positive cultures. Group B streptococcus (GBS) and Escherichia coli were the most commonly isolated organisms (GBS: 95% of all gram-positive sepsis; E coli: 76% of all gram-negative sepsis) from culture-positive patients. Culture-negative patients were found to have a significantly lower mortality rate compared with culture positive patients (16.6% versus 26.9%, P < .001). The incidence of intracranial hemorrhage (ICH) was greater in culture-positive neonates when compared with culture negative (27.6% versus 20.1%, P < .05). There was no difference in the incidence of ICH or eventual outcome between gram-positive and gram-negative sepsis. The culture-positive, septic neonate who requires ECMO support appears to be at an increased risk for intracranial hemorrhage and death. Intracranial hemorrhage appears to be the primary factor affecting survival in these patients. The etiologic organism does not affect the incidence of ICH or outcome. Frequent head ultrasounds and strict control of coagulation parameters are recommended in this patient population.

Malignant solid tumors in neonates: a 40-year review

To evaluate the outcome of neonatal malignant solid tumors, we reviewed the records of 222 infants under the age of 1 year with malignant disease who were treated at the University of Texas M.D. Anderson Cancer Center over a 40-year period. Forty-five cases of neonatal (< 30 days old at the time of presentation) malignancies were found. Thirty-two infants had solid tumors and form the basis of this report. Diagnoses included soft tissue sarcoma (13), brain tumor (5), neuroblastoma (6), retinoblastoma (3), malignant melanoma (2), hemangiopericytoma (2), and nephroblastoma (1). The mean age at which initial signs and symptoms were noted was 9 days of life. Fifty-nine percent (19) presented within the first week of life, and 47% (15) presented at birth. The mean age at histological diagnosis was 54 days. The head and neck region was the most common site (18), followed by trunk (9), and extremities (5). Thirty-one patients underwent surgical resection of the primary tumor. Thirteen of those neonates received no additional chemotherapy and/or radiation therapy, whereas 18 received some combination of surgery plus perioperative chemotherapy and/or radiation therapy. Overall survival was 78% (25 of 32) with an average follow-up of 8 years (range, 2 months to 29 years). There were no survivors among those patients with distant metastatic disease at the time of diagnosis. Despite delays, prognosis is excellent in the absence of distant metastatic disease, particularly for extracranial tumors.

A second course of extracorporeal membrane oxygenation in the neonate--is there a benefit?

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is an effective therapy for infants with severe respiratory failure and pulmonary hypertension. In most patients once the disease reverses, it does not recur. However, in some patients pulmonary hypertension recurs and these infants meet criteria for a second course of ECMO. We evaluated the survival rate and feasibility of a second course of ECMO in neonates.

METHODS

A questionnaire was sent to all active ECMO programs that requested data about patients who received two courses of ECMO. A retrospective review of the results from responding centers was performed to evaluate indications and outcome.

RESULTS

The overall survival rate for the 58 neonates was 40%. Thirty-four patients with congenital diaphragmatic hernia had a survival rate of 47%, and 12 infants with primary persistent pulmonary hypertension had an 8% survival rate (p < 0.05). Most patients were treated with venoarterial ECMO for both courses.

CONCLUSIONS

There is a reasonable survival rate for selected neonates who are treated with a second course of ECMO. Infants with primary persistent pulmonary hypertension should be carefully examined before institution of a second course of ECMO.

Effect of ductal patency on organ blood flow and pulmonary function in the preterm baboon with hyaline membrane disease

OBJECTIVE

To examine the effect of early ductal ligation vs. maintenance of ductal patency on vital organ perfusion and pulmonary function in premature baboons with hyaline membrane disease.

DESIGN

Randomized, controlled interventional study to compare early ligation with formalin infiltration of the ductus arteriosus.

SETTING

Animal care facility at a dedicated research foundation.

SUBJECTS

Eighteen premature baboons delivered by hysterotomy at 140 +/- 2 day gestation.

INTERVENTION

Nine premature baboons underwent formalin infiltration of the ductus arteriosus (group 1), and nine underwent ductal ligation (group 2). Surgical ligation or formalin infiltration was performed at 2 to 4 hrs of age. Animals were maintained on mechanical ventilation and ventilator parameters were adjusted to maintain PaO2 and PaCO2 within the physiologic range.

MAIN OUTCOME MEASURES

Left ventricular output indexed to body weight and vital organ perfusion were measured at 24 hrs of age by the radiolabeled microsphere method. Lung mechanics, including lung wet/dry weight ratio, total lung water, static compliance and functional residual capacity were measured immediately following euthanasia.

RESULTS

Total pulmonary blood flow was significantly lower (p = .0001) in group 2 (mean = 94 mL/min/kg), compared with group 1 (mean = 287 mL/min/kg). Systemic blood flow and effective pulmonary blood flow were higher in group 1 (p = .07). No significant difference between groups in absolute organ blood flow was noted, although flow as a percent of left ventricular index was significantly higher in all organs except the kidney in group 2. There was no difference in arterial blood gas values, parameters of mechanical ventilation, percent lung water, or postmortem measurement of lung mechanics between groups.

CONCLUSION

Early ductal ligation did not result in improved cardiac output, increased organ blood flow, or improved pulmonary function. We postulate that gradual constriction of the ductus arteriosus may play an important role in successful cardiovascular adaptation in the premature infant. While it is clear that premature infants with symptomatic patent ductus arteriosus often benefit from ductal closure, we question the practice of prophylactic early ductal closure.

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 Children's 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.

ECMO for left ventricular assist in a newborn with critical aortic stenosis

Extracorporeal membrane oxygenation (ECMO) has been used in neonates for a variety of disease states including congenital diaphragmatic hernia, meconium aspiration syndrome, sepsis, and postoperative cardiac compromise. To our knowledge, ECMO has not been employed prior to cardiac catheterization in critical aortic stenosis (CAS). We report a neonatal case of CAS where ECMO was used early as a form of left ventricular assist to achieve adequate systemic perfusion and oxygenation and reduce myocardial ischemia. The patient was maintained on ECMO during subsequent attempts at cardiac catheterization, balloon valvuloplasty, and operative valvotomy.

Utility of sonography in the diagnosis of bronchopulmonary sequestration

Sonography in six patients with pulmonary sequestration demonstrated findings associated with and indicative of that diagnosis. The most useful feature, which was seen in three cases and is diagnostic of sequestration, is the identification of an anomalous systemic artery arising from the aorta.

Comparison of different techniques of stapled bowel anastomoses in a canine model

OBJECTIVE

To evaluate different methods of creating a stapled enteroanastomosis and to determine which method would create a larger anastomosis.

DESIGN

Prospective comparison of three groups with a total of 17 mongrel dogs.

SETTING

Clinical investigation facility.

MAIN OUTCOME MEASURES

Stapled side-to-side enteroanastomoses were created with the stapled edges touching or separated. Anastomoses were created in both functional bowel and in a defunctionalized limb. The anastomotic circumference was measured in a blinded fashion after 28 days. The third group had anastomoses created and measured the same day. Groups were compared using the t test.

RESULTS

There was significant narrowing after healing with both types of anastomoses. Anastomoses created by separating the stapled lines were larger than those fashioned with the cut edges touching, both immediately and after healing.

CONCLUSIONS

While clinically significant narrowing of a stapled anastomosis is uncommon, separating the staple lines of a functional end-to-end anastomosis may be the preferable method.

Hormonal response of the premature primate to operative stress

There are few data on the hormonal response to operation in the premature infant. Studies examining the response of newborn human infants have been performed on patients beyond the first few days of life, where some adaptation to postnatal life has occurred. This study evaluated the response of the newly born premature primate to surgical stress. Premature baboons (75% gestation) were intubated, mechanically ventilated and underwent thoracotomy at 2 hours of life with exposure of the ductus arteriosus (PDA). In group 1, formalin was infiltrated to keep the ductus patent. In group 2, the PDA was ligated. Controls had no operation. Blood was drawn at 0, 6, 24, 48, 72, and 96 hours of age. Echocardiograms were performed to confirm patency or closure of the ductus and to monitor cardiac function. Epinephrine, norepinephrine, renin, and cortisol levels were measured. Cortisol levels rose in all groups. Operation stimulated a marked increase in catecholamine and renin levels in both operative groups, which was more marked in the group with PDA ligation at 24 hours. These data reflect expected pathophysiology since early PDA ligation exerts additional hemodynamic demand on the heart. In conclusion, the premature primate is able to mount a significant and severity-dependent endocrine response to stress.

Cefepime for infections of the biliary tract

Antibiotic treatment of biliary tract infections is widely accepted. An open, prospective, randomized, multicenter trial comparing cefepime (2 grams every 12 hours) with gentamicin (1.5 milligrams per kilograms every eight hours) plus mezlocillin (3 grams every four hours) for a minimum of five days was undertaken. Of the 149 patients enrolled, 120 were evaluable; 80 were randomized to receive cefepime and 40 were randomized to receive gentamicin plus mezlocillin (two to one randomization schedule). The diagnosis was acute cholecystitis in 101 patients and acute cholangitis in the remainder. There were no differences between the two treatment groups with regard to gender, age, disease, signs and symptoms, admitting temperature or laboratory values. All patients (100 percent) treated with gentamicin and mezlocillin were cured of the infection, as were 78 (97.5 percent) of the patients treated with cefepime (difference not significant). The incidence and spectrum of adverse events and complications were similar between the two groups (8.8 percent for cefepime versus 10 percent for gentamicin and mezlocillin). Our data show that the efficacy and safety of cefepime administered every 12 hours is equivalent to that of gentamicin and mezlocillin combination for treating patients with acute infections of the biliary tract. In addition, twice-daily administration of cefepime may be more cost-effective than the aminoglycoside-based combination.

Prosthetic diaphragm reconstruction in the growing animal

Widespread use of extracorporeal membrane oxygenation (ECMO) has allowed an increasing number of infants with total agenesis of the diaphragm to survive. Polytetrafluoroethylene (PTFE) is the most widely used material for reconstruction. However, recurrent hernia is a growing problem; PTFE also does not grow with the patient. This study evaluated different materials for diaphragmatic reconstruction in growing animals. Sprague-Dawley rats with a mean weight of 93 g were anesthetized and underwent laparotomy. The control group had an incision into the diaphragm with primary repair. The other three groups underwent complete removal of the left hemidiaphragm and were randomly assigned to one of three reconstruction methods: oxidized cellulose, polyglactin mesh, or a 1-mm PTFE patch. All patch materials were sewn around the ribs circumferentially and into the membranous portion of the central diaphragm medially with 4-0 silk. Thirty-seven animals survived operation, were followed with weekly chest radiographs, and were killed when they reached 400 g. The radiographs were reviewed in a blinded fashion by two observers as were the necropsies, and rib deformity was graded on a scale of 0 to 3. Histological examination of several animals from each group was performed. There was significantly greater rib deformity (2.0 v 0.2, P < .01) in the PTFE group versus controls with 5 of 10 animals also having a smaller thorax. The PTFE pulled away from the chest wall in the animals leaving a fibrous remnant anteriorly. The polyglactin group had significantly more animals with eventration (P < .03, 7/10) compared with all others.(ABSTRACT TRUNCATED AT 250 WORDS)

Congenital diaphragmatic hernia. Stabilization and repair on ECMO

Availability of extracorporeal membrane oxygenation (ECMO) support and the potential advantages of delayed repair of congenital diaphragmatic hernia (CDH) have led several centers to delay CDH repair, using ECMO support if necessary. This study reviews the combined experience of five ECMO centers with infants who underwent stabilization with ECMO and repair of CDH while still on ECMO. All infants were symptomatic at birth, with a mean arterial oxygen pressure (PaO2) of 34 mmHg on institution of bypass despite maximal ventilatory support. A total of 42 infants were repaired on ECMO, with 18 (43%) surviving. Seven infants had total absence of the diaphragm, and 28 required a prosthetic patch to close the defect. Only five infants ever achieved a best postductal PaO2 over 100 mmHg before institution of ECMO. Prematurity was a significant risk factor, with no infants younger than 37 weeks of age surviving. Significant hemorrhage on bypass was also a hallmark of a poor outcome, with 10 of the 24 nonsurvivors requiring five thoracotomies and six laparotomies to control bleeding, whereas only one survivor required a thoracotomy to control bleeding. In follow-up, nine of the 18 survivors (50%) have developed recurrent herniation and seven (43%) have significant gastroesophageal reflux. Importantly, five of the 18 survivors were in the extremely high-risk group who never achieved a PaO2 over 100 mmHg or an arterial carbon dioxide pressure (PaCO2) less than 40 mmHg before the institution of ECMO. In conclusion, preoperative stabilization with ECMO and repair on bypass may allow some high-risk infants to survive. Surviving infants will require long-term follow-up because many will require secondary operations.