Pediatric surgery. First of two parts

Enthusiasm, evidence and ethics: the triple E of minimally invasive pediatric surgery

Minimally invasive techniques are applicable in more than 60% of abdominal and thoracic operations in children. Enthusiasts promoted these techniques for many years. However, level 1 evidence on advantages of minimally invasive surgery in children remains limited. Randomized controlled trials have been conducted for some types of procedures such as laparoscopic appendectomy, fundoplication, pyloromyotomy, and inguinal hernia repair. The results of these studies confirm some advantages of minimally invasive surgery, but for most types of laparoscopic and all types of thoracoscopic procedures, such data remain to be established. This article also focuses on reports on complications and disadvantages which are relevant for final conclusions and recommendations. The ethical implications of the application of new techniques in children are also discussed. On the basis of evidence based data and ethical principles, minimally invasive techniques may be appropriately used in the future.

Physiological impact of pneumoperitoneum on gastric mucosal CO2 pressure during laparoscopic versus open appendectomy in children

INTRODUCTION

Funded knowledge about the physiological impact of laparoscopic surgery in children is sparse. Although there are data on hemodynamic compromise after creation of a pneumoperitoneum in children, little is known about microcirculatory changes at the mucosa level. Therefore, the aim of this study was to assess gastric microcirculation by continuous gastric air tonometry in the setting of laparoscopic versus open appendectomy.

PATIENTS AND METHODS

Twenty children 5-17 years old undergoing laparoscopic and 7 children undergoing open appendectomy were included in the study. Gastric intramucosal CO(2) pressure (pCO(2)i) was measured under standardized flow and intraperitoneal pressure using continuous air tonometry (TONOCAP(®), Datex Ohmeda), and ΔpCO(2) (pCO(2)i - end-expiratory CO(2) pressure [pCO(2)e]) was obtained for the time course of surgery.

RESULTS

ΔpCO(2) increased significantly from the baseline value not only in the laparoscopic group but also in the open surgery group. Even though ΔpCO(2) was higher in the laparoscopic group at all time points, the overall increase in ΔpCO(2) for both groups was uniform. The largest differences were observed during the initial 20 minutes of the operation. The changes observed were exclusively due to an increase of pCO(2)i in relation to a constant pCO(2)e.

DISCUSSION

In the setting of a standardized, simple operation in an otherwise healthy child above the age of 5 years, our data suggest that the effect of a pneumoperitoneum on splanchnic perfusion is comparable to the compromise caused by open surgery. Further research must be obtained when evaluating the full impact of laparoscopy in children.

Defecation disorders in children after surgery for Hirschsprung disease

BACKGROUND AND OBJECTIVE

The majority of children with Hirschsprung disease (HD) after corrective surgery (CS) develop protracted defecation disorders (DDs) such as constipation, fecal incontinence, and/or enterocolitis. The aim of this investigation was to determine the diagnoses, therapies, and long-term clinical outcomes using a systematic algorithm to address protracted DD in children with HD after CS.

METHODS

Retrospective review of children with HD after CS cared for using a systematic algorithm at a tertiary care center. Potential anatomic etiologies were evaluated for first. Clinical outcome was categorized into 4 groups based on symptom severity, time interval from last enterocolitis episode, laxative usage, and/or rectal therapies at the time of last follow-up.

RESULTS

Fifty-seven children were identified, of whom 51 (89.5%) had obstructive symptoms and/or enterocolitis and 6 (10.5%) had nonretentive fecal incontinence. Nonintractable constipation responsive to laxatives was identified in 10 (17.5%), colonic dysmotility in 4 (7.0%), nonrelaxing anal sphincter as a primary etiology in 22 (38.6%), bacterial overgrowth in 2 (3.5%), food intolerance in 2 (3.5%), and rapid transit in 2 (3.5%). Further surgical intervention was undertaken in 22 (38.6%), including 9 (15.8%) for residual aganglionosis. Mean follow-up was 41.4 ± 4.5 months. Clinical outcomes were excellent in 16 (28.1%), good in 22 (38.6%), fair in 1 (1.8%), and poor in 18 (31.6%). Children with enterocolitis were more likely to have an excellent or good clinical outcome.

CONCLUSIONS

The majority of children with HD and protracted DD after CS have a favorable long-term clinical outcome when following a systematic algorithm.

Type A esophageal atresia: a critical review of management strategies at a single center

PURPOSE

The purpose of was to study the short- and long-term outcomes in the management of isolated esophageal atresia with different operative strategies.

METHODS

All patients undergoing type A atresia repair over a 15-year period were included. Demographic data, birth weight, gestational age, incidence of associated anomalies, management, and long-term outcomes were studied.

RESULTS

Fifteen patients with type A atresia (9 male) were treated in the study period. The mean gestational age was 35.5 weeks (range, 27-39 weeks), and the mean birth weight was 2179 g (range, 670-3520 g). Eight babies had associated anomalies. Thirteen patients underwent gastrostomy as the initial procedure, and 2 underwent the Foker procedure. In the delayed management group, 9 patients underwent primary anastomosis, with 2 patients needing proximal pouch myotomy. Two patients underwent a Collis gastroplasty. Two patients underwent a cervical esophagostomy and a gastric tube replacement at 4 months and 1 year, respectively. Eight patients (60%) in this group had anastomotic leaks. All patients are currently on prokinetics and proton pump inhibitors. Seven required antireflux surgery. The median length of hospital admission was 4 months (range, 3-19 months). The native esophagus was preserved in 13 (85%) of 15 babies. All patients are alive, and 14 of 15 are capable of feeding orally.

CONCLUSIONS

Type A esophageal atresia continues to be associated with significant morbidity despite advances in surgical technique and intensive care.

Management of fetal lung lesions

Prenatal diagnosis provides insight into the in utero evolution of fetal thoracic lesions such as congenital cystic adenomatoid malformation (CCAM), bronchopulmonary sequestration (BPS), congenital lobar emphysema, and mediastinal teratoma. Serial sonographic study of fetuses with thoracic lesions has helped define the natural history of these lesions, determine the pathophysiologic features that affect clinical outcome, and formulate management based on prognosis.

Thoracoscopy versus thoracotomy improves midterm musculoskeletal status and cosmesis in infants and children

BACKGROUND

It has been postulated that video-assisted thoracoscopic surgery (VATS) achieves a better biometric and aesthetic outcome than conventional thoracic surgery (CTS), but data are lacking. We aimed to compare the midterm effects of both approaches in children.

METHODS

Sixty-two infants and children, who underwent VATS (34; 55%) or CTS (28; 45%) for benign thoracic conditions, were evaluated at follow-up after a mean of 3.8 years (1 to 7 years). The patients underwent standardized clinical assessment of the skeletal system and function. The intercostal spaces were investigated for rib fusion by ultrasound. Patients (+/- parents) themselves, as well as clinicians, subsequently assessed the scars.

RESULTS

Comparing the operated versus nonoperated sides, chest asymmetry was significantly less frequent after VATS versus CTS in the horizontal plane (mean relative difference 0.996 +/- 0.003 vs 0.964 +/- 0.008, p < 0.001) and in nipple location (mean relative difference 0.985 +/- 0.008 vs 0.949 +/- 0.013, p = 0.047). The ranges of motion of the shoulder joints did not differ significantly. However, the incidence of scoliosis was lower in VATS patients (9% vs 54%, p < 0.001) and the intercostal spaces of the operated hemithoraces were narrower after CTS (p < 0.001). The Manchester scar assessment scores were in favor of VATS (mean 7.5 vs 13.1, p < 0.001). The visual analog scale scores recorded by patients-parents and independent observers were also significantly better after VATS. Patient satisfaction was less with CTS as 10% wanted to have the scar revised, compared with none in the VATS group.

CONCLUSIONS

The thoracoscopic versus conventional approach to the thoracic cavity in children is associated with significantly less midterm musculoskeletal sequelae and a better cosmetic outcome.

Large bowel obstruction in an adult after Soave for Hirschsprung's disease in childhood

Whereas Hirschsprung's disease is usually managed by surgery in infancy, late complications in adult life are rarely described. We report on a 36-year-old male presenting with an unusual complication after definitive treatment of Hirschsprung's disease as an infant.

Neonatal anesthesia

The physiology of the preterm and term neonate is characterized by a high metabolic rate, limited pulmonary, cardiac and thermoregulatory reserve, and decreased renal function. Multisystem immaturity creates important developmental differences in drug handling and response when compared to the older child or adult. Neonatal anesthetic management requires an understanding of the pharmacophysiologic limitations of the neonate as well as the pathophysiology of coexisting surgical disease. This review addresses the pertinent aspects of neonatal physiology and pharmacology, general considerations in the anesthetic care of surgical neonates, and concludes with a brief review of the anesthetic management of neonates with necrotizing enterocolitis, diaphragmatic hernia, and tracheoesophageal fistula.

Stapled anopexy for short segment Hirschprungs disease in adults

Traditional treatment of short segment Hirschprungs disease in adult consists of major resectional procedures, often with the use of a temporary stoma. Patients with this disease may have significant morbidities that increase their risk of post-operative morbidity and mortality. In an attempt to minimize the procedural related morbidity, we describe the application of the stapled anopexy technique to treat short segment Hirschprungs disease.

Fetal surgery for lung lesions, congenital diaphragmatic hernia, and sacrococcygeal teratoma

After more than 2 decades of experimental and clinical work, fetal surgery is an accepted treatment option for highly selected fetuses with life-threatening anomalies. Fetal lung masses associated with hydrops are nearly 100% fatal. These lesions can be resected in utero if they are predominantly solid or multicystic. Thoracoamniotic shunt placement may be effective in the setting of a single large cyst. Fetuses diagnosed with left congenital diaphragmatic hernia before 26 weeks' gestation with associated liver herniation and a low right lung to head circumference ratio have a relatively poor prognosis with conventional therapy after birth, but in utero therapeutic approaches have yet to show a comparative survival benefit. A prospective randomized trial is required to critically evaluate the efficacy of fetal tracheal occlusion for severe diaphragmatic hernia. Fetal sacrococcygeal teratoma complicated with progressive high output cardiac failure may benefit from in utero resection of the tumor.

Can 'long-gap' esophageal atresia be safely managed at home while awaiting anastomosis?

BACKGROUND

Neonates with "long gap" esophageal atresia (EA) are often managed with gastrostomy and tube drainage of the proximal pouch for a number of months while awaiting definitive repair. Because of the risk of aspiration and need for complex nursing care, most remain hospitalized during this time. However, prolonged hospitalization utilizes scarce resources and may be difficult for many families.

METHODS

The authors report on 5 patients who were treated successfully at home while awaiting esophageal anastomosis.

RESULTS

Four patients had pure EA (one had a duodenal atresia), and one had a distal fistula. Gestational ages ranged from 31 to 41 weeks. All had a gastrostomy within days of birth. Age at definitive repair ranged from 6 to 12 months. Time at home while awaiting anastomosis ranged from 42 to 113 days. Care at home included nursing care, suction equipment and training, gastrostomy feeding, and ability to perform cardiopulmonary resuscitation. The only complications noted while at home consisted of ear infection in one patient and recurrent upper respiratory tract infections in another patient.

CONCLUSIONS

Selected patients with long gap esophageal atresia can be treated safely at home while awaiting esophageal anastomosis. Success of this approach depends on a motivated, reliable family, and adequate support from community health care providers.

Challenging embryological theories on congenital diaphragmatic hernia: future therapeutic implications for paediatric surgery

Lung hypoplasia is central to the poor prognosis of babies with congenital diaphragmatic hernia (CDH). Prolapse of abdominal organs through a diaphragmatic defect has traditionally been thought to impair lung growth by compression. The precise developmental biology of CDH remains unresolved. Refractory to fetal correction, lung hypoplasia in CDH may instead originate during embryogenesis and before visceral herniation. Resolving these conflicting hypotheses may lead to reappraisal of current clinical strategies. Genetic studies in murine models and the fruitfly, Drosophila melanogaster are elucidating the control of normal respiratory organogenesis. Branchless and breathless are Drosophila mutants lacking fibroblast growth factor (FGF) and its cognate receptor (FGFR), respectively. Sugarless and sulphateless mutants lack enzymes essential for heparan sulphate (HS) biosynthesis. Phenotypically, all these mutants share abrogated airway branching. Mammalian organ culture and transgenic models confirm the essential interaction of FGFs and HS during airway ramification. Embryonic airway development (branching morphogenesis) occurs in a defined spatiotemporal sequence. Unlike the surgically-created lamb model, the nitrofen rat model permits investigation of embryonic lung growth in CDH. Microdissecting embryonic lung primordia from the nitrofen CDH model and normal controls, we demonstrated that disruption of stereotyped airway branching correlates with and precedes subsequent CDH formation. To examine disturbed branching morphogenesis longitudinally, we characterised a system that preserves lung hypoplasia in organ culture. We tested FGFs and heparin (an HS analogue) as potential therapies on normal and hypoplastic lungs. Observing striking differences in morphological response to FGFs between normal and hypoplastic lung primordia, we postulated abnormalities of FGF/HS signalling in the embryonic CDH lung. Evaluating this hypothesis further, we examined effects of an HS-independent growth factor (epidermal growth factor, EGF) on hypoplastic lung development. Visible differences in morphological response indicate an intrinsic abnormality of hypoplastic lung primordia that may involve shared targets of FGFs and EGE. These studies indicate that lung hypoplasia precedes diaphragmatic hernia and may involve disturbances of mitogenic signalling pathways fundamental to embryonic lung development. What does this imply for human CDH? Fetal surgery may be 'too little, too late' to correct an established lung embryopathy. In utero growth factor therapy may permit antenatal lung rescue. Prevention of the birth defect by preconceptual prophylaxis may represent the ultimate solution.

Neonatal surgical emergencies: stabilization and management

The transitional period following birth can be complicated by the presence of congenital anomalies requiring emergent surgical management. Newborns with congenital diaphragmatic hernia require immediate intubation and gastric decompression to minimize gastric distention, as well as cautious ventilation to avoid pneumothorax. Newborns with omphalocele and gastroschisis are at risk for bacterial contamination, as well as heat and evaporative losses from exposed viscera. These newborns benefit from the use of a protective bowel bag. Newborns with meningomyelocele require meticulous care to avoid infection and trauma to exposed portions of the spinal cord. An illustrated protocol provides guidance in the initial stabilization of these defects. Nurses providing family-centered care must be knowledgeable about congenital anomalies presenting at birth so they can properly stabilize these newborns and provide accurate information to families.

Advances in fetal and neonatal surgery for gastrointestinal anomalies and disease

The last decade has seen considerable improvement in the understanding and treatment of neonatal surgical disorders. Translation of basic molecular biology research to clinical practice has directly improved the understanding and treatment of a number of congenital, developmental disorders, such as Hirschsprung's disease and congenital hyperinsulinism. Miniaturized instruments and improved optics have permitted increased use of videoscopic and minimally invasive techniques to even the smallest infants. Continued improvements in prenatal imaging will permit enhanced understanding of the prenatal natural history of congenital structural disorders and the development of more specific therapies. Finally, rigorous clinical research tools have begun to be applied to rare pediatric surgical disorders with the use of organized multicenter trials. It is an exciting time for all involved in the care of neonates.

Applications of robotic surgery in pediatric patients

Minimally invasive surgery is increasingly becoming the standard approach to treatment for pediatric patients. Infants present a technical challenge due to the small size of structures and the small workspace available. Master-slave robotic surgical telemanipulators help overcome this challenge by facilitating microsurgery in a confined workspace. The Zeus Robotic Surgical System (Computer Motion, Inc., Goleta, CA, U.S.A.) was used to develop the robotic approach and to evaluate the technical feasibility of performing four technically challenging procedures that are typically performed in infants. Robotic enteroenterostomy, hepaticojejunostomy, portoenterostomy, and esophagoesophagostomy were performed in piglets and compared with the same procedures performed by standard minimally invasive techniques. Enteroenterostomy, hepaticojejunostomy, and esophagoesophagostomy procedures were successfully developed and are technically feasible. The portoenterostomy procedure needs further study to validate data from the second set of experiments, showing a lower complication rate in the robotic group. Survivor studies are needed to fully elucidate the advantages that may be provided by the robotic approach.

The "diaphanous" diaphragm: a radiographic sign seen after patch repair of congenital diaphragmatic hernia in neonates

OBJECTIVE

The purpose of this study was to describe the radiographic features and etiology of the "diaphanous" (translucent) diaphragm. This sign, which, to our knowledge, has not previously been described, is a transient phenomenon seen on chest radiographs, after surgical patch repair of congenital diaphragmatic hernia.

CONCLUSION

The diaphanous diaphragm is a consequence of air trapped in the porous polytetrafluoroethylene graft that creates an intragraft radiolucency apparent on postoperative chest radiographs obtained within the first 24 hr. This radiolucency is transient and gradually disappears over the first few postoperative days as the air is replaced by granulation tissue. This sign should be recognized and not mistaken for a persistent pneumothorax after repair of a congenital diaphragmatic hernia.

Technical assessment of porcine enteroenterostomy performed with ZEUS robotic technology

BACKGROUND/PURPOSE

Limitations of minimally invasive pediatric surgery include the inability to perform precise anastomoses of 2 to 15 mm. Robotic technology facilitates the performance of endoscopic microsurgical procedures. This study examined the technical feasibility of performing an enteroenterostomy in piglets utilizing ZEUS robotic technology.

METHODS

Ten piglets (6.5 to 8.5 kg) underwent enteroenterostomy. Standard laparoscopic techniques were used in the control group (n = 5), and ZEUS robotic technology was used in the experimental group (n = 5). AESOP controlled the camera in both groups. Anesthesia time; surgery time; robotic set-up time; and anastomotic time, patency, diameter, and integrity were compared.

RESULTS

No statistical difference existed between the means of the control and experimental groups for anesthesia time (176.0 v 154.0 minute; P =.63), surgery time (143.0 v 139.2 minute; P =.92), anastomosis time (109.4 v 93.0 minutes; P =.56), AESOP set-up time (4.2 v 7.0 minutes; P =.51), and anastomotic diameter (7.062 v 7.362 mm; P =.62). All anastomoses were patent without narrowing. The ZEUS cases averaged 14 minutes faster than the standard laparoscopic cases, even with the ZEUS set-up time included.

CONCLUSIONS

These data supports the hypothesis that robotic-assisted enteroenterostomy is technically feasible. ZEUS robotic technology will potentially play an important role in expanding the applications of minimally invasive pediatric surgery.