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Error traps and culture of safety in the treatment of abdominal wall defects
Seminars in Pediatric Surgery 28 (2019) 124–130
Contents lists available at ScienceDirect
Seminars in Pediatric Surgery journal homepage: www.elsevier.com/locate/sempedsurg
Error traps and culture of safety in the treatment of abdominal wall defects Sherif Emil Department of Pediatric Surgery, The Montreal Children’s Hospital, McGill University Health Centre, Room B04.2028, 1001 Decarie Boulevard, Montreal, QC H4A 3J1, Canada
a r t i c l e
i n f o
Keywords: Gastroschisis Omphalocele Abdominal wall defects Safety Errors
a b s t r a c t The importance of defining and implementing a culture of safety in pediatric surgery is being increasingly seen as essential to decreasing complications and improving outcomes. The concept of a safety culture is a universal one, but the elements of such a culture are different for every disease and anomaly treated. In this paper, I will review these elements as they pertain to the treatment of abdominal wall defects starting from fetal evaluation to post-discharge care. © 2019 Elsevier Inc. All rights reserved.
Introduction The publication of the landmark study, “To Err Is Human”, by the United States Institute of Medicine at the turn of the century heralded a new era in health care, where institution of a culture of safety became increasingly recognized as fundamental to optimizing outcomes and minimizing complications.1 This culture of safety can be described as a health care environment where deliberate efforts are exerted to prevent avoidable medical errors at both the practitioner and system levels. While the institution of a culture of safety has not been frequently addressed in pediatric surgery, recent publications have pointed to increasing recognition of the importance of such a culture in pediatric surgical care.2-5 Due to the diversity of conditions treated, and operations performed, by pediatric surgeons, the elements of a safety culture may differ for different conditions. However, any safety culture must also be cognizant of error traps, described as a method that works well in most circumstances but which is apt to fail under certain conditions.6,7 For example, in gastroschisis, use of the silastic silo can be a classic error trap. The silo is thought to protect against compartment syndrome, is quite easy to use, and has a favorable safety profile. However, under certain circumstances, the silo can result in disastrous complications.8,9 The two main abdominal wall defects treated by pediatric surgeons are gastroschisis and omphalocele. For both anomalies, a culture of safety starts with the unborn patient. Decisions regarding fetal follow-up, delivery mode and timing, and delivery site should be made with the intention of minimizing immediate postnatal complications. The surgeon’s therapeutic role includes closure of
E-mail address: [email protected] https://doi.org/10.1053/j.sempedsurg.2019.04.015 1055-8586/© 2019 Elsevier Inc. All rights reserved.
the defect, and treating potential intestinal complications. A number of error traps can occur during performance of these tasks. Finally, adequate patient follow-up is essential to ensure long-term safety. The pediatric surgeon is typically the only physician who follows the child from birth (or before birth) onward, and is therefore at the center of continuity of care for the child. Despite the existence of a large body of literature on all aspects of diagnosis and treatment of abdominal wall defects, there are virtually no publications that have specifically addressed iatrogenic avoidable complications of these anomalies. Although the two defects share several aspects, they are different enough to warrant separate discussions Gastroschisis Outcomes In a number of publications from high-income countries, gastroschisis has been repeatedly shown to be associated with excellent survival and long-term outcomes. The most important outcome determinant in gastroschisis is the presence or absence of intestinal complications, including atresia, volvulus, necrosis, perforation, and short bowel syndrome.10 An objective risk stratification system that takes these potential complications into account is the Gastroschisis Prognostic Score (GPS), created using the prospective gastroschisis database of the Canadian Pediatric Surgery Network (CAPSnet).11,12 This score can be easily calculated upon the first examination of the patient, and helps establish the severity of the condition along the spectrum of gastroschisis. In the absence of intestinal complications, the condition is referred to as simple gastroschisis and survival now approaches 100%.13 Even in the presence of intestinal complications, survival to discharge is above 90%, and long-term survival exceeds 80%.13,14 Despite these ex-
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Fig. 1. A typical case of closing gastroschisis.
cellent outcomes, gastroschisis bowel should be considered fragile bowel that has already been subjected to a major in-utero insult. A second post-natal insult is often all that is necessary to result in a very poor outcome for an individual patient. Perinatal care The care of a gastroschisis patient begins with fetal assessment. Gastroschisis is usually seen on the mid second trimester ultrasound performed at 18–20 weeks gestational age. The anomaly is diagnosed when a para-umbilical abdominal wall defect, typically to the right of the midline, is seen along with herniation of freefloating bowel into the amniotic cavity. The diagnosis of gastroschisis immediately warrants closer follow of the pregnancy, due to increased risk of intrauterine growth restriction, preterm labor, and intrauterine fetal demise.15–17 Biweekly fetal ultrasound should be performed, increasing in frequency if there is suspicion of impending or present complications. In addition to diagnosis and follow-up, fetal ultrasound has been used to attempt to predict intestinal complications. Oakes et al. recently reviewed the literature on this subject.17 A number of sonographic markers that may potentially predict intestinal complications, or complex gastroschisis, have been studied. These include location, extent, and onset of bowel dilation, the trajectory of such dilation, gastric dilation, and bowel wall thickening.17 Of these, intra-abdominal bowel dilation appears to be the most reliable antenatal predictor of complex gastroschisis.17 Evidence of in utero intestinal perforation may also be seen on fetal ultrasound, prompting early delivery.18 A particularly devastating variant of complex gastroschisis is closing gastroschisis. This represents an in-utero narrowing of the defect that essentially strangulates the extra-abdominal bowel, typically resulting in atresias at the abdominal entry and exit points, as shown in Fig. 1.14 Cases of closing gastroschisis may manifest a triad of intra-abdominal bowel dilation, stability or shrinkage of the extra-abdominal bowel, and a small defect size.19,20 High suspicion of closing gastroschisis is one of the few indications for early delivery. Such a case is shown in Figs. 2 and 3. The evolving ultrasound findings of a male fetus with gastroschisis showed progressive intra-abdominal bowel dilation with stable extra-abdominal dilation (Fig. 2), raising the suspicion of closing gastroschisis. The baby was delivered at 35 weeks. A closing gastroschisis was confirmed with a tight ring and fusion of the fascia to the mesentery, but fortunately the bowel had not progressed
to atresia or necrosis (Fig. 3). An error trap in the fetal management of gastroschisis is to consider premature delivery always disadvantageous to the fetus. It usually is, but in some circumstances, it can be life-saving. Another important aspect of perinatal management is to decide on the safest site of delivery of the mother and care of the infant after birth.21 A number of studies have looked at the effect of transfer after birth on outcomes of gastroschisis.21 Most of the evidence points to an improvement in gastroschisis outcomes when infants are born at, or treated at, higher volume centers and higher level neonatal intensive care units.21 In a recent CAPSnet study, outborn status was associated with a higher incidence of necrotizing enterocolitis in gastroschisis patients.22 Therefore, whenever possible, mothers carrying a baby with gastroschisis should ideally be delivered at a facility that eliminates the need for transport of the infant and provides the highest level of neonatal and pediatric surgical expertise. Closure For almost three decades following Moore’s landmark paper on gastroschisis, surgeons essentially had only two options to close the defect, namely primary closure or suturing synthetic material to the fascial ring to create a temporary silo.23 In 1995, Fischer et al. published the first experience of deliberate staged closure of gastroschisis with the pre-formed spring-loaded silo.24 The next major advance in closure techniques occurred with the popularization of sutureless closure techniques by Bianchi and Sandler.25,26 Current options for closure of the abdominal wall defect include immediate or staged reduction with sutured or sutureless closure. Petrosyan and Sandler recently reviewed these options, and offered an algorithm that can help surgeons choose among the various options.27 The two major error traps in abdominal wall closure include failure to predict or diagnose compartment syndrome after closure, and bowel compromise during primary or staged closure. Abdominal compartment syndrome is almost exclusively a complication of primary closure, particularly if sutured fascial closure is undertaken. An intra-abdominal pressure less than 15 mmHg is considered safe, while higher pressures will likely increase the risk of compartment syndrome. Intra-abdominal pressure can be measured using intra-gastric or intra-vesical catheters. These are not always easy to employ in neonates, and are not widely used. The safest approach to prevent intestinal injury is to immediately release the closure
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Fig. 2. Ultrasound findings in closing gastroschisis.
and close observation of the contents and configuration of the silo throughout its use. These principles are demonstrated in the following video: https://www.youtube.com/watch?v=vizFAf4R6Kk. An example of segmental bowel compromise within a silo is shown in Fig. 4. In this case, the segment of bowel was resected, a primary anastomosis was performed, and a new silo was placed. If complications due to the firm ring are encountered, it is best to cut the ring and suture the silo directly to the skin or fascial margins. Complex gastroschisis
Fig. 3. Postnatal findings of closing gastroschisis without intestinal compromise.
and decompress the abdomen using a silo if there are any worrisome signs of an impending compartment syndrome . These include a significant increase in peak or mean inspiratory pressures, decreased urine output, a new requirement for vasopressor support, or unexplained metabolic acidosis. As mentioned earlier, despite the avoidance of compartment syndrome, the spring-loaded silo can also result in bowel compromise by a variety of routes, including pressure necrosis by the silo ring, compression of the root of the mesentery, or intestinal volvulus within the silo.8,9,14 Safe principles of silo use include lysis of any adhesions to the fascial ring, choice of appropriate silo size, ensuring no trapped bowel between the silo and abdominal wall, appropriate tension on the silo to avoid pressure on abdominal organs, avoidance of mesenteric torsion, minimizing silo duration by performing closure as soon as near complete reduction is achieved,
As mentioned earlier, complex gastroschisis is used to describe patients who have suffered in-utero bowel compromise in the form of atresia, necrosis, perforation, or a combination of insults. The severity of gastroschisis in these patients is therefore defined by the patient. These can be the most challenging patients from both a diagnostic and therapeutic approach.28 In some cases, the bowel insult is readily identifiable after birth. In other cases, severe bowel matting (graded as 4 in the GPS) can obscure the existence of other complications. An error trap in evaluation of the bowel is to assume that severe matting implies significant bowel loss or compromise. Fig. 5 demonstrates such a scenario. In this newborn girl, the appearance of the bowel at birth did not allow determination of the degree of viability of the intestine or the possible presence of atresia. The large cystic-appearing area (A) represented fluid accumlation in the lesser sac. The bowel was placed in a 7.5 cm silo and reduced over 8 days. Three weeks after fascial closure, the patient demonstrated bowel function and was subsequently discharged on full oral feedings. She has never been re-admitted during eight years of follow-up. Care of patients with complex gastroschisis should be individualized, depending on the gestational age, bowel insult, length of
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Fig. 4. Segmental bowel gangrene within a spring-loaded silo.
Fig. 5. Severe bowel matting. @ birth (A and B) and at closure after 8 days of silo reduction.
bowel remaining, any comorbidities, and the general status of the patient. However, there are several principles of safe surgical care in these patients. Closure should be customized and should take into account potential future procedures that may be required to address the bowel complications. Bowel necrosis and perforation should be addressed immediately after birth. Immediate bowel resection and primary anastomosis are not contra-indicated in appropriate patients and should not be delayed as a routine practice. The surgical goals should be to establish bowel continuity as early as possible, preserve maximum bowel length, and address potentially dysfunctional dilated bowel. Given the frequent poor motility of gastroschisis bowel, contrast studies of the bowel may be unable to diagnose stenosis or missed atresia. Exploration is there-
fore required if there is prolonged bowel obstruction. A gastrostomy should be placed early in cases of short bowel syndrome. Bowel resection will be necessary at some point in most patients with complex gastroschisis. Surgeons are often reluctant to explore obstructed bowel early in these patients, and often resort to diversion versus primary anastomosis. A surgical dictum of waiting six weeks before exploring a patient with complex gastroschisis is not supported by evidence.28,29 Exploration and establishment of intestinal continuity may be performed two to three weeks after birth. Early establishment of bowel continuity may represent one of the few opportunities for potentially improving the outcomes of complex gastroschisis patients. If the bowel blood supply is tenuous and/or distal obstruction cannot be ruled out, it is best to delay primary anastomosis for two reasons. First, the
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status of the bowel will improve with time. Second, contrast studies may be performed to elucidate the anatomy and rule out other points of obstruction. Diverting stomas should be rarely needed in gastroschisis patients, and should be avoided if short bowel syndrome is likely to exist. Post-operative care and follow-up Total parenteral nutrition is required in all patients with gastroschisis, and is in fact the major factor that differentiates care and survival between high-income and low-income countries. This should be continued until bowel function returns. Due to concern about necrotizing enterocolitis, many patients are progressed very slowly on enteral feeds. This leads to prolonged central venous access. In fact, necrotizing enterocolitis is quite rare in gastroschisis patients.22 There is no evidence that slow progression of enteral feeds is protective. On the other hand, central-line associated blood stream infections are the most important predictors of morbidity in the form of prolonged total parenteral nutrition and hospital stay in simple gastroschisis patients.22 Therefore, once bowel function returns, feedings should progress as tolerated and central lines should be removed as soon as feasible. Gastroschisis patients may represent with bowel obstruction after discharge. An error trap in such patients is to assume that all obstructions are due to adhesions. In fact, bowel obstructions that occur in the first year may be due to intestinal stenosis that becomes symptomatic once the child starts to consume solid feedings. Highgrade small obstructions that occur early in life and do not resolve after a short period of medical management should therefore be explored. Obstructions that occur later in life are typically due to adhesions and can be treated like any adhesive small bowel obstruction. Omphalocele Outcomes Population-based outcome studies of patients with omphalocele are less common than those of patients with gastroschisis.30,31 This is perhaps due to the significant difference in outcome determinants between the two anomalies. Gastroschisis outcomes are typically dictated by the anomaly itself, whereas omphalocele outcomes are typically dictated by associated anomalies and chromosomal syndromes.31 Overall survival in patients with omphalocele is less than 75%, with the worst survival seen in patients with chromosomal anomalies and low birth weight.31 Major cardiac anomalies are also encountered in about one-third of all patients with omphalocele.31 These anomalies often dictate management and outcomes. Perinatal care Like gastroschisis, omphalocele is usually a prenatal diagnosis. In the case of omphalocele, a contained herniation within a membranous sac is seen through the umbilical ring. Color flow Doppler shows cord insertion directly into the umbilical sac of an omphalocele. An extracorporeal liver is also commonly seen in large omphaloceles. In some cases, fetal ultrasound may not be able to differentiate a ruptured omphalocele from a gastroschisis. As in gastroschisis, there has been a search for fetal sonographic variables that may predict outcomes of omphalocele. The finding of herniated liver implies a large defect and confers the term “giant omphalocele.” To avoid such qualitative terms, certain indices, such as omphalocele diameter divided by head circumference, or omphalocele diameter divided by abdominal circumference, have
been used to objectively describe the size of an omphalocele and the likelihood of successful postnatal closure.32,33 Although associated anomalies and chromosomal syndromes may be diagnosed on fetal ultrasound, a significant proportion of fetuses with apparently isolated omphalocele will be found to have additional anomalies on postnatal work-up. Therefore, an error trap is to assume that an isolated omphalocele on fetal ultrasound is in fact an isolated anomaly. Performing fetal magnetic resonance imaging on patients with omphalocele to screen for other anomalies has been proposed. Although the evidence is quite weak, most pediatric surgeons recommend a Cesarean section delivery if liver is herniated. This is due to concern about the possibility of omphalocele rupture and liver hemorrhage during a vaginal delivery. A Cesarean section may maximize safety during delivery and prevent immediate complications. The issues pertaining to fetal follow-up and delivery site are similar for omphalocele and gastroschisis. Associated anomalies As mentioned above, associated anomalies may occur in up to 50% of patients with omphalocele. Anomalies may be seen in the neurologic, cardiac, pulmonary, and renal systems.34 Omphaloceles may also be seen in association with lethal malformations, such as the Pentalogy of Cantrell, or those associated with very high morbidity, such as cloacal exstrophy. Syndromes associated with omphalocele include Beckwith-Weidemann, Marshall-Smith, and Meckel-Gruber. Omphaloceles are also seen in association with Trisomy 13 and Trisomy 18.34 A more recently understood association exists between giant omphalocele and pulmonary hypertension, with or without pulmonary hypoplasia.35 It may be seen in up to one third of patients with giant omphalocele. Although it does not appear to increase mortality, it significantly increases morbidity through prolonged mechanical ventilation and hospital stay. Therefore, it is best to allow a period of at least 24 h of observation before any intervention for large omphaloceles. The onset of pulmonary hypertension and requirement for mechanical ventilation in these patients will help inform closure decisions. Closure In omphaloceles containing only bowel, closure is usually quite straight forward. The bowel in these patients is not injured or matted. Reduction and defect closure is typically easily accomplished. Large omphaloceles with liver herniation present both decisionmaking and technical challenges. In addition to exacerbating underlying cardiorespiratory morbidities, closure can result in compartment syndrome and decreased venous return due to kinking of the hepatic veins. A systematic way to proceed is to use the algorithm shown in Fig. 6. If the baby is premature or has significant cardiorespiratory comorbidities that result in oxygen dependence, respiratory insufficiency, or hemodynamic instability, the baby is best served by omitting any surgical procedure and resorting to escharization of the sac.36 An error trap in the case of mechanically ventilated patients is to assume that mechanical ventilation will allow safe reduction and closure. The most common agent used for escharization currently is silver sulfadiazine which is applied to the sac once or twice daily. A controlled ventral hernia results and can be closed in one or more procedures later in life after the cardiorespiratory morbidities have been addressed. This treatment is shown in Figs. 7 and 8. This baby boy had a presumptive diagnosis of isolated omphalocele but developed respiratory distress and evidence of pulmonary hypertension during the first 24 h of life, followed by a subsequent
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Fig. 6. Decision tree for omphalocele closure.
Fig. 9. Giant omphalocele containing the entire liver in a term baby girl with no associated anomalies. Fig. 7. Early results of omphalocele escharization.
Fig. 10. Single stage reduction and closure. Fig. 8. Closure at 18 months of age after successful omphalocele escharization.
diagnosis of aortic coarctation. Silver sulfadiazine application started on the second day of life and continued for several weeks. Repair of the defect without need for component separation was successful at 18 months of age. If the baby is not premature and does not appear to have any significant cardiorespiratory comorbidity after 24–48 h observation, the goal should be to obtain complete fascial closure during the first few weeks of life in a primary or staged manner. Primary
closure can be attempted and is often successful in many large defects containing all or most of the liver. The surgeon can get an impression of abdominal domain by examining the abdomen. In some patients, the abdomen will appear “empty” despite a large omphalocele. In giant omphaloceles, the rectus muscles are always far apart. Transverse closure may be easier. An example of such a patient is shown in Figs. 9 and 10. In many cases, part of the sac is stuck to the live surface. An error trap is to insist on complete
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removal of the sac prior to reduction. This often incites a significant liver capsular hemorrhage, and is unnecessary. If the contents cannot be reduced due to lack of abdominal domain, or if the closure results in substantially increased mean airway pressures or hemodynamic compromise, the surgeon can either use a biologic mesh to close the abdomen or convert to a staged closure by installing a spring-loaded or sutured silo, with or without an abdominal expander. If the omphalocele sac is intact and unattached to the viscera, the redundant sac can be used as a silo. Vacuum assisted closure (VAC) has also proven useful in these difficult cases. Conclusion Many outcomes in patients with abdominal wall defects are defined by the disease itself or associated anomalies. Preventable complications, some of which can be lethal, are more likely to occur due to judgment errors, rather than technical mishaps. Like every area in pediatric surgery, a culture of safety can be instituted in the care of patients with abdominal wall defects. Such a culture demands an understanding of all the error traps that can occur, as well as all potential options in the care of the patient. References 1. Institute of Medicine (US). To Err is human: Building a Safer Health System. Committee on quality of health care in America. Washington, DC: National Academies Press (US); 20 0 0. 2. Berman L, Rangel S, Goldin A, et al. Safety culture among pediatric surgeons: a national survey of attitudes and perceptions of patient safety. J Pediatr Surg. 2018;53:381–395. 3. Skarsgard ED. Recommendations for surgical safety checklist use in Canadian children’s hospitals. Can J Surg. 2016;59(3):161–166. 4. Tsao K1, Browne M. Culture of safety: a foundation for patient care. Semin Pediatr Surg. 2015;24(6):283–2877. 5. Macdonald AL, Sevdalis N. Patient safety improvement interventions in children’s surgery: a systematic review. J Pediatr Surg. 2017;52:504–511. 6. Reason J. Human error: models and management. BMJ. 20 0 0;320:768–770. 7. Strasberg SM. Error traps and vasculo-biliary injury in laparoscopic and open cholecystectomy. J Hepatobiliary Pancreat Surg. 2008;15(3):284–292. 8. Ryckman J1, Aspirot A, Laberge JM, et al. Intestinal venous congestion as a complication of elective silo placement for gastroschisis. Semin Pediatr Surg. 2009;18(2):109–112. 9. Abadir J, Emil S, Nguyen N. Abdominal foregut perforations in children: a 10-year experience. J Pediatr Surg. 2005;40(12):1903–1907. 10. Molik KA, Gingalewski CA, West KW, et al. Gastroschisis: a plea for risk categorization. J Pediatr Surg. 2001;36(1):51–55. 11. Cowan KN, Puligandla PS, Laberge J-M, et al. The gastroschisis prognostic score: reliable outcome prediction in gastroschisis. J Pediatr Surg. 2012;47(6):1111–1117.
12. Puligandla PS, Baird R, Skarsgard ED, et al. Outcome prediction in gastroschisis: the gastroschisis prognostic score (GPS) revisited. J Pediatr Surg. 2017;52(May):718–721. 13. Youssef F, Cheong LH, Emil S. Gastroschisis outcomes in North America: a comparison of Canada and the United States. J Pediatr Surg. 2016;51(6):891–895. 14. Emil S, Canvasser N, Chen T, et al. Contemporary 2-year outcomes of complex gastroschisis. J Pediatr Surg. 2012;47(8):1521–1522. 15. Brantberg A, Blaas HG, Salvesen KA, et al. Surveillance and outcome of fetuses with gastroschisis. Ultrasound Obstet Gynecol. 2004;23(1):4–13. 16. South AP, Stutey KM, Meinzen-Derr J. Metaanalysis of the prevalence of intrauterine fetal death in gastroschisis. Am J Obstet Gynecol. 2013;209 114.e111-113. 17. Oakes MC, Porto M, Chung JH. Advances in prenatal and perinatal diagnosis and management of gastroschisis. Semin Pediatr Surg. 2018;27(5):289–299. 18. Chung JH, Norton C, Emil S. Sour grapes: ultrasound abnormalities spurred delivery and neonatal surgery. Am J Obstet Gynecol. 2009;332:e1–e2. 19. Houben C, Davenport M, Ade-Ajayi N, et al. Closing gastroschisis: diagnosis, management, and outcomes. J Pediatr Surg. 2009;44(2):343–347. 20. Geslin D, Clermidi P, Gatibelza ME, et al. What prenatal ultrasound features are predictable of complex or vanishing gastroschisis? A retrospective study. Prenat Diagn. 2017;37(2):168–175. 21. Taylor JS, Shew SB. Impact of societal factors and health care delivery systems on gastroschisis outcomes. Semin Pediatr Surg. 2018;27(5):316–320. 22. Youssef F, Laberge JM, Puligandla P, et al. Determinants of outcomes in patients with simple gastroschisis. J Pediatr Surg. 2017;52(5):710–714. 23. Moore T. Gastroschisis with antenatal evisceration of intestines and urinary bladder. Ann Surg. 1963;158(2):263–269. 24. Fischer JD, Chun K, Moores DC, Andrews HG. Gastroschisis: a simple technique for staged silo closure. J Pediatr Surg. 1995;30(8):1169–1171. 25. Bianchi A, Dickson AP, Alizai NK. Elective delayed midgut reduction-No anesthesia for gastroschisis: selection and conversion criteria. J Pediatr Surg. 2002;37(9):1334–1336. 26. Sandler A, Lawrence J, Meehan, et al. A “plastic” sutureless abdominal wall closure in gastroschisis. J Pediatr Surg. 2004;39(5):738–741. 27. Petrosyan M, Sandler AD. Closure methods in gastroschisis. Semin Pediatr Surg. 2018;27(5):304–308. 28. Emil S. Surgical strategies in complex gastroschisis. Semin Pediatr Surg. 2018;27(5):309–315. 29. Alshehri A, Emil S, Laberge JM, et al. Outcomes of early versus late intestinal operations in patients with gastroschisis and intestinal atresia: results from a prospective national database. J Pediatr Surg. 2013;48(10):2022–2026. 30. Kong JY, Yeo KT, Abdel-Latif ME, et al. Outcomes of infants with abdominal wall defects over 18years. J Pediatr Surg. 2016;51(10):1644–1649. 31. Marshall J1, Salemi JL, Tanner JP, et al. Prevalence, correlates, and outcomes of omphalocele in the United States, 1995-2005. Obstet Gynecol. 2015;126(2):284–293. 32. Fawley JA, Peterson EL, Christensen MA, et al. Can omphalocele ratio predict postnatal outcomes? J Pediatr Surg. 2016;51(1):62–66. 33. Montero FJ, Simpson LL, Brady PC, et al. Fetal omphalocele ratios predict outcomes in prenatally diagnosed omphalocele. Am J Obstet Gynecol. 2011;205 284.e1-7. 34. Corey KM, Hornik CP, Laughon MM, et al. Frequency of anomalies and hospital outcomes in infants with gastroschisis and omphalocele. Early Hum Dev. 2014;90(8):421–424. 35. Partridge EA, Hanna BD, Panitch HB, et al. Pulmonary hypertension in giant omphalocele infants. J Pediatr Surg. 2014;49(12):1767–1770. 36. Akinkuotu AC, Sheikh F, Olutoye OO, et al. Giant omphaloceles: surgical management and perinatal outcomes. J Surg Res. 2015;198(2):388–392.
Contents lists available at ScienceDirect
Seminars in Pediatric Surgery journal homepage: www.elsevier.com/locate/sempedsurg
Error traps and culture of safety in the treatment of abdominal wall defects Sherif Emil Department of Pediatric Surgery, The Montreal Children’s Hospital, McGill University Health Centre, Room B04.2028, 1001 Decarie Boulevard, Montreal, QC H4A 3J1, Canada
a r t i c l e
i n f o
Keywords: Gastroschisis Omphalocele Abdominal wall defects Safety Errors
a b s t r a c t The importance of defining and implementing a culture of safety in pediatric surgery is being increasingly seen as essential to decreasing complications and improving outcomes. The concept of a safety culture is a universal one, but the elements of such a culture are different for every disease and anomaly treated. In this paper, I will review these elements as they pertain to the treatment of abdominal wall defects starting from fetal evaluation to post-discharge care. © 2019 Elsevier Inc. All rights reserved.
Introduction The publication of the landmark study, “To Err Is Human”, by the United States Institute of Medicine at the turn of the century heralded a new era in health care, where institution of a culture of safety became increasingly recognized as fundamental to optimizing outcomes and minimizing complications.1 This culture of safety can be described as a health care environment where deliberate efforts are exerted to prevent avoidable medical errors at both the practitioner and system levels. While the institution of a culture of safety has not been frequently addressed in pediatric surgery, recent publications have pointed to increasing recognition of the importance of such a culture in pediatric surgical care.2-5 Due to the diversity of conditions treated, and operations performed, by pediatric surgeons, the elements of a safety culture may differ for different conditions. However, any safety culture must also be cognizant of error traps, described as a method that works well in most circumstances but which is apt to fail under certain conditions.6,7 For example, in gastroschisis, use of the silastic silo can be a classic error trap. The silo is thought to protect against compartment syndrome, is quite easy to use, and has a favorable safety profile. However, under certain circumstances, the silo can result in disastrous complications.8,9 The two main abdominal wall defects treated by pediatric surgeons are gastroschisis and omphalocele. For both anomalies, a culture of safety starts with the unborn patient. Decisions regarding fetal follow-up, delivery mode and timing, and delivery site should be made with the intention of minimizing immediate postnatal complications. The surgeon’s therapeutic role includes closure of
E-mail address: [email protected] https://doi.org/10.1053/j.sempedsurg.2019.04.015 1055-8586/© 2019 Elsevier Inc. All rights reserved.
the defect, and treating potential intestinal complications. A number of error traps can occur during performance of these tasks. Finally, adequate patient follow-up is essential to ensure long-term safety. The pediatric surgeon is typically the only physician who follows the child from birth (or before birth) onward, and is therefore at the center of continuity of care for the child. Despite the existence of a large body of literature on all aspects of diagnosis and treatment of abdominal wall defects, there are virtually no publications that have specifically addressed iatrogenic avoidable complications of these anomalies. Although the two defects share several aspects, they are different enough to warrant separate discussions Gastroschisis Outcomes In a number of publications from high-income countries, gastroschisis has been repeatedly shown to be associated with excellent survival and long-term outcomes. The most important outcome determinant in gastroschisis is the presence or absence of intestinal complications, including atresia, volvulus, necrosis, perforation, and short bowel syndrome.10 An objective risk stratification system that takes these potential complications into account is the Gastroschisis Prognostic Score (GPS), created using the prospective gastroschisis database of the Canadian Pediatric Surgery Network (CAPSnet).11,12 This score can be easily calculated upon the first examination of the patient, and helps establish the severity of the condition along the spectrum of gastroschisis. In the absence of intestinal complications, the condition is referred to as simple gastroschisis and survival now approaches 100%.13 Even in the presence of intestinal complications, survival to discharge is above 90%, and long-term survival exceeds 80%.13,14 Despite these ex-
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Fig. 1. A typical case of closing gastroschisis.
cellent outcomes, gastroschisis bowel should be considered fragile bowel that has already been subjected to a major in-utero insult. A second post-natal insult is often all that is necessary to result in a very poor outcome for an individual patient. Perinatal care The care of a gastroschisis patient begins with fetal assessment. Gastroschisis is usually seen on the mid second trimester ultrasound performed at 18–20 weeks gestational age. The anomaly is diagnosed when a para-umbilical abdominal wall defect, typically to the right of the midline, is seen along with herniation of freefloating bowel into the amniotic cavity. The diagnosis of gastroschisis immediately warrants closer follow of the pregnancy, due to increased risk of intrauterine growth restriction, preterm labor, and intrauterine fetal demise.15–17 Biweekly fetal ultrasound should be performed, increasing in frequency if there is suspicion of impending or present complications. In addition to diagnosis and follow-up, fetal ultrasound has been used to attempt to predict intestinal complications. Oakes et al. recently reviewed the literature on this subject.17 A number of sonographic markers that may potentially predict intestinal complications, or complex gastroschisis, have been studied. These include location, extent, and onset of bowel dilation, the trajectory of such dilation, gastric dilation, and bowel wall thickening.17 Of these, intra-abdominal bowel dilation appears to be the most reliable antenatal predictor of complex gastroschisis.17 Evidence of in utero intestinal perforation may also be seen on fetal ultrasound, prompting early delivery.18 A particularly devastating variant of complex gastroschisis is closing gastroschisis. This represents an in-utero narrowing of the defect that essentially strangulates the extra-abdominal bowel, typically resulting in atresias at the abdominal entry and exit points, as shown in Fig. 1.14 Cases of closing gastroschisis may manifest a triad of intra-abdominal bowel dilation, stability or shrinkage of the extra-abdominal bowel, and a small defect size.19,20 High suspicion of closing gastroschisis is one of the few indications for early delivery. Such a case is shown in Figs. 2 and 3. The evolving ultrasound findings of a male fetus with gastroschisis showed progressive intra-abdominal bowel dilation with stable extra-abdominal dilation (Fig. 2), raising the suspicion of closing gastroschisis. The baby was delivered at 35 weeks. A closing gastroschisis was confirmed with a tight ring and fusion of the fascia to the mesentery, but fortunately the bowel had not progressed
to atresia or necrosis (Fig. 3). An error trap in the fetal management of gastroschisis is to consider premature delivery always disadvantageous to the fetus. It usually is, but in some circumstances, it can be life-saving. Another important aspect of perinatal management is to decide on the safest site of delivery of the mother and care of the infant after birth.21 A number of studies have looked at the effect of transfer after birth on outcomes of gastroschisis.21 Most of the evidence points to an improvement in gastroschisis outcomes when infants are born at, or treated at, higher volume centers and higher level neonatal intensive care units.21 In a recent CAPSnet study, outborn status was associated with a higher incidence of necrotizing enterocolitis in gastroschisis patients.22 Therefore, whenever possible, mothers carrying a baby with gastroschisis should ideally be delivered at a facility that eliminates the need for transport of the infant and provides the highest level of neonatal and pediatric surgical expertise. Closure For almost three decades following Moore’s landmark paper on gastroschisis, surgeons essentially had only two options to close the defect, namely primary closure or suturing synthetic material to the fascial ring to create a temporary silo.23 In 1995, Fischer et al. published the first experience of deliberate staged closure of gastroschisis with the pre-formed spring-loaded silo.24 The next major advance in closure techniques occurred with the popularization of sutureless closure techniques by Bianchi and Sandler.25,26 Current options for closure of the abdominal wall defect include immediate or staged reduction with sutured or sutureless closure. Petrosyan and Sandler recently reviewed these options, and offered an algorithm that can help surgeons choose among the various options.27 The two major error traps in abdominal wall closure include failure to predict or diagnose compartment syndrome after closure, and bowel compromise during primary or staged closure. Abdominal compartment syndrome is almost exclusively a complication of primary closure, particularly if sutured fascial closure is undertaken. An intra-abdominal pressure less than 15 mmHg is considered safe, while higher pressures will likely increase the risk of compartment syndrome. Intra-abdominal pressure can be measured using intra-gastric or intra-vesical catheters. These are not always easy to employ in neonates, and are not widely used. The safest approach to prevent intestinal injury is to immediately release the closure
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Fig. 2. Ultrasound findings in closing gastroschisis.
and close observation of the contents and configuration of the silo throughout its use. These principles are demonstrated in the following video: https://www.youtube.com/watch?v=vizFAf4R6Kk. An example of segmental bowel compromise within a silo is shown in Fig. 4. In this case, the segment of bowel was resected, a primary anastomosis was performed, and a new silo was placed. If complications due to the firm ring are encountered, it is best to cut the ring and suture the silo directly to the skin or fascial margins. Complex gastroschisis
Fig. 3. Postnatal findings of closing gastroschisis without intestinal compromise.
and decompress the abdomen using a silo if there are any worrisome signs of an impending compartment syndrome . These include a significant increase in peak or mean inspiratory pressures, decreased urine output, a new requirement for vasopressor support, or unexplained metabolic acidosis. As mentioned earlier, despite the avoidance of compartment syndrome, the spring-loaded silo can also result in bowel compromise by a variety of routes, including pressure necrosis by the silo ring, compression of the root of the mesentery, or intestinal volvulus within the silo.8,9,14 Safe principles of silo use include lysis of any adhesions to the fascial ring, choice of appropriate silo size, ensuring no trapped bowel between the silo and abdominal wall, appropriate tension on the silo to avoid pressure on abdominal organs, avoidance of mesenteric torsion, minimizing silo duration by performing closure as soon as near complete reduction is achieved,
As mentioned earlier, complex gastroschisis is used to describe patients who have suffered in-utero bowel compromise in the form of atresia, necrosis, perforation, or a combination of insults. The severity of gastroschisis in these patients is therefore defined by the patient. These can be the most challenging patients from both a diagnostic and therapeutic approach.28 In some cases, the bowel insult is readily identifiable after birth. In other cases, severe bowel matting (graded as 4 in the GPS) can obscure the existence of other complications. An error trap in evaluation of the bowel is to assume that severe matting implies significant bowel loss or compromise. Fig. 5 demonstrates such a scenario. In this newborn girl, the appearance of the bowel at birth did not allow determination of the degree of viability of the intestine or the possible presence of atresia. The large cystic-appearing area (A) represented fluid accumlation in the lesser sac. The bowel was placed in a 7.5 cm silo and reduced over 8 days. Three weeks after fascial closure, the patient demonstrated bowel function and was subsequently discharged on full oral feedings. She has never been re-admitted during eight years of follow-up. Care of patients with complex gastroschisis should be individualized, depending on the gestational age, bowel insult, length of
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Fig. 4. Segmental bowel gangrene within a spring-loaded silo.
Fig. 5. Severe bowel matting. @ birth (A and B) and at closure after 8 days of silo reduction.
bowel remaining, any comorbidities, and the general status of the patient. However, there are several principles of safe surgical care in these patients. Closure should be customized and should take into account potential future procedures that may be required to address the bowel complications. Bowel necrosis and perforation should be addressed immediately after birth. Immediate bowel resection and primary anastomosis are not contra-indicated in appropriate patients and should not be delayed as a routine practice. The surgical goals should be to establish bowel continuity as early as possible, preserve maximum bowel length, and address potentially dysfunctional dilated bowel. Given the frequent poor motility of gastroschisis bowel, contrast studies of the bowel may be unable to diagnose stenosis or missed atresia. Exploration is there-
fore required if there is prolonged bowel obstruction. A gastrostomy should be placed early in cases of short bowel syndrome. Bowel resection will be necessary at some point in most patients with complex gastroschisis. Surgeons are often reluctant to explore obstructed bowel early in these patients, and often resort to diversion versus primary anastomosis. A surgical dictum of waiting six weeks before exploring a patient with complex gastroschisis is not supported by evidence.28,29 Exploration and establishment of intestinal continuity may be performed two to three weeks after birth. Early establishment of bowel continuity may represent one of the few opportunities for potentially improving the outcomes of complex gastroschisis patients. If the bowel blood supply is tenuous and/or distal obstruction cannot be ruled out, it is best to delay primary anastomosis for two reasons. First, the
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status of the bowel will improve with time. Second, contrast studies may be performed to elucidate the anatomy and rule out other points of obstruction. Diverting stomas should be rarely needed in gastroschisis patients, and should be avoided if short bowel syndrome is likely to exist. Post-operative care and follow-up Total parenteral nutrition is required in all patients with gastroschisis, and is in fact the major factor that differentiates care and survival between high-income and low-income countries. This should be continued until bowel function returns. Due to concern about necrotizing enterocolitis, many patients are progressed very slowly on enteral feeds. This leads to prolonged central venous access. In fact, necrotizing enterocolitis is quite rare in gastroschisis patients.22 There is no evidence that slow progression of enteral feeds is protective. On the other hand, central-line associated blood stream infections are the most important predictors of morbidity in the form of prolonged total parenteral nutrition and hospital stay in simple gastroschisis patients.22 Therefore, once bowel function returns, feedings should progress as tolerated and central lines should be removed as soon as feasible. Gastroschisis patients may represent with bowel obstruction after discharge. An error trap in such patients is to assume that all obstructions are due to adhesions. In fact, bowel obstructions that occur in the first year may be due to intestinal stenosis that becomes symptomatic once the child starts to consume solid feedings. Highgrade small obstructions that occur early in life and do not resolve after a short period of medical management should therefore be explored. Obstructions that occur later in life are typically due to adhesions and can be treated like any adhesive small bowel obstruction. Omphalocele Outcomes Population-based outcome studies of patients with omphalocele are less common than those of patients with gastroschisis.30,31 This is perhaps due to the significant difference in outcome determinants between the two anomalies. Gastroschisis outcomes are typically dictated by the anomaly itself, whereas omphalocele outcomes are typically dictated by associated anomalies and chromosomal syndromes.31 Overall survival in patients with omphalocele is less than 75%, with the worst survival seen in patients with chromosomal anomalies and low birth weight.31 Major cardiac anomalies are also encountered in about one-third of all patients with omphalocele.31 These anomalies often dictate management and outcomes. Perinatal care Like gastroschisis, omphalocele is usually a prenatal diagnosis. In the case of omphalocele, a contained herniation within a membranous sac is seen through the umbilical ring. Color flow Doppler shows cord insertion directly into the umbilical sac of an omphalocele. An extracorporeal liver is also commonly seen in large omphaloceles. In some cases, fetal ultrasound may not be able to differentiate a ruptured omphalocele from a gastroschisis. As in gastroschisis, there has been a search for fetal sonographic variables that may predict outcomes of omphalocele. The finding of herniated liver implies a large defect and confers the term “giant omphalocele.” To avoid such qualitative terms, certain indices, such as omphalocele diameter divided by head circumference, or omphalocele diameter divided by abdominal circumference, have
been used to objectively describe the size of an omphalocele and the likelihood of successful postnatal closure.32,33 Although associated anomalies and chromosomal syndromes may be diagnosed on fetal ultrasound, a significant proportion of fetuses with apparently isolated omphalocele will be found to have additional anomalies on postnatal work-up. Therefore, an error trap is to assume that an isolated omphalocele on fetal ultrasound is in fact an isolated anomaly. Performing fetal magnetic resonance imaging on patients with omphalocele to screen for other anomalies has been proposed. Although the evidence is quite weak, most pediatric surgeons recommend a Cesarean section delivery if liver is herniated. This is due to concern about the possibility of omphalocele rupture and liver hemorrhage during a vaginal delivery. A Cesarean section may maximize safety during delivery and prevent immediate complications. The issues pertaining to fetal follow-up and delivery site are similar for omphalocele and gastroschisis. Associated anomalies As mentioned above, associated anomalies may occur in up to 50% of patients with omphalocele. Anomalies may be seen in the neurologic, cardiac, pulmonary, and renal systems.34 Omphaloceles may also be seen in association with lethal malformations, such as the Pentalogy of Cantrell, or those associated with very high morbidity, such as cloacal exstrophy. Syndromes associated with omphalocele include Beckwith-Weidemann, Marshall-Smith, and Meckel-Gruber. Omphaloceles are also seen in association with Trisomy 13 and Trisomy 18.34 A more recently understood association exists between giant omphalocele and pulmonary hypertension, with or without pulmonary hypoplasia.35 It may be seen in up to one third of patients with giant omphalocele. Although it does not appear to increase mortality, it significantly increases morbidity through prolonged mechanical ventilation and hospital stay. Therefore, it is best to allow a period of at least 24 h of observation before any intervention for large omphaloceles. The onset of pulmonary hypertension and requirement for mechanical ventilation in these patients will help inform closure decisions. Closure In omphaloceles containing only bowel, closure is usually quite straight forward. The bowel in these patients is not injured or matted. Reduction and defect closure is typically easily accomplished. Large omphaloceles with liver herniation present both decisionmaking and technical challenges. In addition to exacerbating underlying cardiorespiratory morbidities, closure can result in compartment syndrome and decreased venous return due to kinking of the hepatic veins. A systematic way to proceed is to use the algorithm shown in Fig. 6. If the baby is premature or has significant cardiorespiratory comorbidities that result in oxygen dependence, respiratory insufficiency, or hemodynamic instability, the baby is best served by omitting any surgical procedure and resorting to escharization of the sac.36 An error trap in the case of mechanically ventilated patients is to assume that mechanical ventilation will allow safe reduction and closure. The most common agent used for escharization currently is silver sulfadiazine which is applied to the sac once or twice daily. A controlled ventral hernia results and can be closed in one or more procedures later in life after the cardiorespiratory morbidities have been addressed. This treatment is shown in Figs. 7 and 8. This baby boy had a presumptive diagnosis of isolated omphalocele but developed respiratory distress and evidence of pulmonary hypertension during the first 24 h of life, followed by a subsequent
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Fig. 6. Decision tree for omphalocele closure.
Fig. 9. Giant omphalocele containing the entire liver in a term baby girl with no associated anomalies. Fig. 7. Early results of omphalocele escharization.
Fig. 10. Single stage reduction and closure. Fig. 8. Closure at 18 months of age after successful omphalocele escharization.
diagnosis of aortic coarctation. Silver sulfadiazine application started on the second day of life and continued for several weeks. Repair of the defect without need for component separation was successful at 18 months of age. If the baby is not premature and does not appear to have any significant cardiorespiratory comorbidity after 24–48 h observation, the goal should be to obtain complete fascial closure during the first few weeks of life in a primary or staged manner. Primary
closure can be attempted and is often successful in many large defects containing all or most of the liver. The surgeon can get an impression of abdominal domain by examining the abdomen. In some patients, the abdomen will appear “empty” despite a large omphalocele. In giant omphaloceles, the rectus muscles are always far apart. Transverse closure may be easier. An example of such a patient is shown in Figs. 9 and 10. In many cases, part of the sac is stuck to the live surface. An error trap is to insist on complete
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removal of the sac prior to reduction. This often incites a significant liver capsular hemorrhage, and is unnecessary. If the contents cannot be reduced due to lack of abdominal domain, or if the closure results in substantially increased mean airway pressures or hemodynamic compromise, the surgeon can either use a biologic mesh to close the abdomen or convert to a staged closure by installing a spring-loaded or sutured silo, with or without an abdominal expander. If the omphalocele sac is intact and unattached to the viscera, the redundant sac can be used as a silo. Vacuum assisted closure (VAC) has also proven useful in these difficult cases. Conclusion Many outcomes in patients with abdominal wall defects are defined by the disease itself or associated anomalies. Preventable complications, some of which can be lethal, are more likely to occur due to judgment errors, rather than technical mishaps. Like every area in pediatric surgery, a culture of safety can be instituted in the care of patients with abdominal wall defects. Such a culture demands an understanding of all the error traps that can occur, as well as all potential options in the care of the patient. References 1. Institute of Medicine (US). To Err is human: Building a Safer Health System. Committee on quality of health care in America. Washington, DC: National Academies Press (US); 20 0 0. 2. Berman L, Rangel S, Goldin A, et al. Safety culture among pediatric surgeons: a national survey of attitudes and perceptions of patient safety. J Pediatr Surg. 2018;53:381–395. 3. Skarsgard ED. Recommendations for surgical safety checklist use in Canadian children’s hospitals. Can J Surg. 2016;59(3):161–166. 4. Tsao K1, Browne M. Culture of safety: a foundation for patient care. Semin Pediatr Surg. 2015;24(6):283–2877. 5. Macdonald AL, Sevdalis N. Patient safety improvement interventions in children’s surgery: a systematic review. J Pediatr Surg. 2017;52:504–511. 6. Reason J. Human error: models and management. BMJ. 20 0 0;320:768–770. 7. Strasberg SM. Error traps and vasculo-biliary injury in laparoscopic and open cholecystectomy. J Hepatobiliary Pancreat Surg. 2008;15(3):284–292. 8. Ryckman J1, Aspirot A, Laberge JM, et al. Intestinal venous congestion as a complication of elective silo placement for gastroschisis. Semin Pediatr Surg. 2009;18(2):109–112. 9. Abadir J, Emil S, Nguyen N. Abdominal foregut perforations in children: a 10-year experience. J Pediatr Surg. 2005;40(12):1903–1907. 10. Molik KA, Gingalewski CA, West KW, et al. Gastroschisis: a plea for risk categorization. J Pediatr Surg. 2001;36(1):51–55. 11. Cowan KN, Puligandla PS, Laberge J-M, et al. The gastroschisis prognostic score: reliable outcome prediction in gastroschisis. J Pediatr Surg. 2012;47(6):1111–1117.
12. Puligandla PS, Baird R, Skarsgard ED, et al. Outcome prediction in gastroschisis: the gastroschisis prognostic score (GPS) revisited. J Pediatr Surg. 2017;52(May):718–721. 13. Youssef F, Cheong LH, Emil S. Gastroschisis outcomes in North America: a comparison of Canada and the United States. J Pediatr Surg. 2016;51(6):891–895. 14. Emil S, Canvasser N, Chen T, et al. Contemporary 2-year outcomes of complex gastroschisis. J Pediatr Surg. 2012;47(8):1521–1522. 15. Brantberg A, Blaas HG, Salvesen KA, et al. Surveillance and outcome of fetuses with gastroschisis. Ultrasound Obstet Gynecol. 2004;23(1):4–13. 16. South AP, Stutey KM, Meinzen-Derr J. Metaanalysis of the prevalence of intrauterine fetal death in gastroschisis. Am J Obstet Gynecol. 2013;209 114.e111-113. 17. Oakes MC, Porto M, Chung JH. Advances in prenatal and perinatal diagnosis and management of gastroschisis. Semin Pediatr Surg. 2018;27(5):289–299. 18. Chung JH, Norton C, Emil S. Sour grapes: ultrasound abnormalities spurred delivery and neonatal surgery. Am J Obstet Gynecol. 2009;332:e1–e2. 19. Houben C, Davenport M, Ade-Ajayi N, et al. Closing gastroschisis: diagnosis, management, and outcomes. J Pediatr Surg. 2009;44(2):343–347. 20. Geslin D, Clermidi P, Gatibelza ME, et al. What prenatal ultrasound features are predictable of complex or vanishing gastroschisis? A retrospective study. Prenat Diagn. 2017;37(2):168–175. 21. Taylor JS, Shew SB. Impact of societal factors and health care delivery systems on gastroschisis outcomes. Semin Pediatr Surg. 2018;27(5):316–320. 22. Youssef F, Laberge JM, Puligandla P, et al. Determinants of outcomes in patients with simple gastroschisis. J Pediatr Surg. 2017;52(5):710–714. 23. Moore T. Gastroschisis with antenatal evisceration of intestines and urinary bladder. Ann Surg. 1963;158(2):263–269. 24. Fischer JD, Chun K, Moores DC, Andrews HG. Gastroschisis: a simple technique for staged silo closure. J Pediatr Surg. 1995;30(8):1169–1171. 25. Bianchi A, Dickson AP, Alizai NK. Elective delayed midgut reduction-No anesthesia for gastroschisis: selection and conversion criteria. J Pediatr Surg. 2002;37(9):1334–1336. 26. Sandler A, Lawrence J, Meehan, et al. A “plastic” sutureless abdominal wall closure in gastroschisis. J Pediatr Surg. 2004;39(5):738–741. 27. Petrosyan M, Sandler AD. Closure methods in gastroschisis. Semin Pediatr Surg. 2018;27(5):304–308. 28. Emil S. Surgical strategies in complex gastroschisis. Semin Pediatr Surg. 2018;27(5):309–315. 29. Alshehri A, Emil S, Laberge JM, et al. Outcomes of early versus late intestinal operations in patients with gastroschisis and intestinal atresia: results from a prospective national database. J Pediatr Surg. 2013;48(10):2022–2026. 30. Kong JY, Yeo KT, Abdel-Latif ME, et al. Outcomes of infants with abdominal wall defects over 18years. J Pediatr Surg. 2016;51(10):1644–1649. 31. Marshall J1, Salemi JL, Tanner JP, et al. Prevalence, correlates, and outcomes of omphalocele in the United States, 1995-2005. Obstet Gynecol. 2015;126(2):284–293. 32. Fawley JA, Peterson EL, Christensen MA, et al. Can omphalocele ratio predict postnatal outcomes? J Pediatr Surg. 2016;51(1):62–66. 33. Montero FJ, Simpson LL, Brady PC, et al. Fetal omphalocele ratios predict outcomes in prenatally diagnosed omphalocele. Am J Obstet Gynecol. 2011;205 284.e1-7. 34. Corey KM, Hornik CP, Laughon MM, et al. Frequency of anomalies and hospital outcomes in infants with gastroschisis and omphalocele. Early Hum Dev. 2014;90(8):421–424. 35. Partridge EA, Hanna BD, Panitch HB, et al. Pulmonary hypertension in giant omphalocele infants. J Pediatr Surg. 2014;49(12):1767–1770. 36. Akinkuotu AC, Sheikh F, Olutoye OO, et al. Giant omphaloceles: surgical management and perinatal outcomes. J Surg Res. 2015;198(2):388–392.