**9.4 Post-surgery intestinal failure and short bowel syndrome**

About 9% of NEC cases result in short bowel syndrome (SBS) with incidence inversely related to GA and almost 42% in intestinal failure and SBS [52, 53]. Such infants suffer from significant malabsorption and are at risk for sepsis, cholestasis, and liver failure due to prolonged parenteral nutrition (PN). It is suggested that infants with residual small bowel length ≤ 10% of expected small bowel length may develop SBS. The cumulative probability of weaning from PN by 24 months is 96% in infants with >50 cm of residual small bowel compared to 38% in those who have <50 cm of residual small bowel. Those with ≥41 cm of residual bowel are significantly more likely to achieve enteral autonomy than those with less than 41 cm [53]. In general, those with post-resection length of remaining bowel less than 25% of the normal small bowel length have higher chances of developing SBS. The length of remaining bowel, however, is not the sole or best predictor of SBS. Infants at risk of SBS are as follows: parenteral antibiotics or mechanical ventilation on the day of onset of NEC, birth weight less than 750 g, enteral nutrition before the diagnosis of NEC, percentage of bowel resected, and placement and duration of a diverting jejunostomy. The intestines continue to grow after resection and contribute to the process of attaining enteral autonomy.

#### **9.5 Surgical procedures for short bowel syndrome**

In a NICHD cohort, 95% of cases of SBS were due to NEC with an overall incidence of 0.7% of infants <1500 g at birth [52]. Approximately 42% of cases of NEC in infants <1500 g of BW who undergo surgery develop intestinal failure and SBS,

**39**

**9.6 Intestinal rehabilitation**

*Necrotizing Enterocolitis*

*DOI: http://dx.doi.org/10.5772/intechopen.85784*

risk factors being lower birth weight, antibiotics use, positive pressure ventilation on the day of NEC, feeding, and lower post-resection length of remaining bowel [53]. Intestinal tailoring and lengthening procedure, also called "autologous intestinal reconstruction surgery" are performed in conditions where likelihood of weaning from PN is low despite rigorous intestinal rehabilitation measures. The criteria for surgery, tentative and not well supported by studies, include dilated small intestine, failure to attain intestinal autonomy, and absence of liver failure and GI dysmotility. The procedures aim at surgical lengthening of the bowel to increase the absorptive area and tapering or plicating the dilated bowel to improve motility. There is not enough literature on the subject to assess its clinical advantage. Bianchi procedure is a longitudinal intestinal lengthening and tailoring procedure (LILT) and may be successful in improving absorption and nutritional status but requires multiple anastomoses. Complications of this procedure include fistula formation, anastomotic stenosis, or leakage and sepsis [54]. The 6-year survival rate is 45%, and survivors have residual bowel length greater than 40 cm and no liver disease. The Bianchi procedure is not recommended in neonates with liver disease or intestine length less than 50 cm. The serial transverse enteroplasty procedure (STEP) is a substitute for LILT which increases the girth of bowel. It has a simpler technique that does not need bowel anastomoses, and the tapering can be performed on dilated bowel. STEP increases intestinal length, improves intestinal absorptive capacity, and may decrease the risk of D-lactic acidosis due to bacterial overgrowth. STEP is more favored over other techniques as the weaning from parenteral nutrition is faster and the need for later transplants lesser. There is no difference in early complications, growth rates, or survival between the two procedures, and nearly half of patients operated achieve enteral autonomy, with the median time to wean from parenteral nutrition (PN) being 21 months postoperatively. Patients whose bowel re-dilates after a lengthening procedure have worse overall outcomes. Complications of STEP include gastrointestinal bleeding, staple line leak, hematoma, abscess formation, stricture, pleural effusion, obstruction, a need for transplantation, and even death. In a recent publication, the rate of independence from PN post-STEP was reported as 58% with parenteral calories decreasing from 71 to 36% within 1 month and to 12% after 1 year. The total increase in intestinal length achieved was about 49% [54]. Small bowel transplantation (SBT) may be considered in patients who have progressive, severe, or irreversible intestinal failure with associated liver disease. Other considerations might be a lack of venous access, recurrent life-threatening central venous catheter-associated sepsis, complete mesenteric thrombosis, slow growing tumors of the hepatic hilum or root of mesentery, or extremely short residual bowel with no chance of achieving enteral autonomy in patients who prefer transplantation over lifelong PN dependence [54]. Small bowel transplantation has a 5-year graft survival rate of 48% with lifelong immunosuppressant medications. Types of transplantation include isolated intestine, isolated liver, combined liver and intestine, and multi-visceral. Complications are rejection, infection, graft-versus-host disease, and posttransplant lymphoproliferative disease. Overall, one year patient and intestine graft survival is 89%, being 79% in intestine and 72% in liver-intestine graft recipients. Patient and intestine graft survival falls to 46% by 10 years. At 10 years the survival of intestine only recipients is 29%, whereas, that of liver-intestine recipients 39-42%. More recently, living donor intestinal transplantation has been

done successfully in pediatric patients which eliminates waiting time.

This requires a multidisciplinary approach. The focus is on optimizing enteral feeding and weaning from PN with judicious use of pharmacotherapy and surgical

#### *Necrotizing Enterocolitis DOI: http://dx.doi.org/10.5772/intechopen.85784*

*Pediatric Surgery, Flowcharts and Clinical Algorithms*

undertaken in the routine management of NEC.

**9.3 Comparison of laparotomy and PPD**

required laparotomy. Six (14%) infants died due to NEC totalis and two of ongoing and recurrent NEC following recovery from the acute episode of each. The authors concluded that laparoscopy is a useful procedure in the management of NEC, with one-fifth of patients not requiring further surgery. However, due to the lack of enough evidence about its utility and benefits, the procedure is generally not

There are limited data about the superiority of one procedure over other. In a multicenter controlled study, 117 infants who were <34 weeks of gestation with perforated NEC were randomized to PPD or laparotomy. No differences were noted in mortality (34.5 versus 35.5%), TPN dependence on postoperative day 90 (47.2 versus 40%), and length of hospital stay (126 ± 58 versus 116 ± 56 days) [49]. A subgroup analysis of cases with extensive pneumatosis intestinalis, GA less than 25 weeks, and serum pH less than 7.30 at presentation showed no significant advantage of one procedure over the other. In another randomized multicenter trial of 69 extremely low birth weight (ELBW) infants with NEC or SIP, no difference in the survival rates was noted between the two interventions, while 74% treated with PPD subsequently required laparotomy [50]. A cohort study from the NICHD neonatal research group reported no difference in mortality rate, and 24% treated with PPD required subsequent laparotomy. Blakely et al. reported that PPD is more likely to result in a composite outcome of death or neurodevelopmental impairment at 18–22 months postmenstrual age [51]. However in their study, PPD was performed in infants who were more premature (gestational age 24.7 versus 25.7 weeks), were more likely to be hypotensive, required higher respiratory support, and were more likely to have a preoperative diagnosis of SIP. Most of these studies are compromised by a lack pf power.

**9.4 Post-surgery intestinal failure and short bowel syndrome**

About 9% of NEC cases result in short bowel syndrome (SBS) with incidence inversely related to GA and almost 42% in intestinal failure and SBS [52, 53]. Such infants suffer from significant malabsorption and are at risk for sepsis, cholestasis, and liver failure due to prolonged parenteral nutrition (PN). It is suggested that infants with residual small bowel length ≤ 10% of expected small bowel length may develop SBS. The cumulative probability of weaning from PN by 24 months is 96% in infants with >50 cm of residual small bowel compared to 38% in those who have <50 cm of residual small bowel. Those with ≥41 cm of residual bowel are significantly more likely to achieve enteral autonomy than those with less than 41 cm [53]. In general, those with post-resection length of remaining bowel less than 25% of the normal small bowel length have higher chances of developing SBS. The length of remaining bowel, however, is not the sole or best predictor of SBS. Infants at risk of SBS are as follows: parenteral antibiotics or mechanical ventilation on the day of onset of NEC, birth weight less than 750 g, enteral nutrition before the diagnosis of NEC, percentage of bowel resected, and placement and duration of a diverting jejunostomy. The intestines continue to grow after resection and contribute to the

In a NICHD cohort, 95% of cases of SBS were due to NEC with an overall incidence of 0.7% of infants <1500 g at birth [52]. Approximately 42% of cases of NEC in infants <1500 g of BW who undergo surgery develop intestinal failure and SBS,

**38**

process of attaining enteral autonomy.

**9.5 Surgical procedures for short bowel syndrome**

risk factors being lower birth weight, antibiotics use, positive pressure ventilation on the day of NEC, feeding, and lower post-resection length of remaining bowel [53]. Intestinal tailoring and lengthening procedure, also called "autologous intestinal reconstruction surgery" are performed in conditions where likelihood of weaning from PN is low despite rigorous intestinal rehabilitation measures. The criteria for surgery, tentative and not well supported by studies, include dilated small intestine, failure to attain intestinal autonomy, and absence of liver failure and GI dysmotility. The procedures aim at surgical lengthening of the bowel to increase the absorptive area and tapering or plicating the dilated bowel to improve motility. There is not enough literature on the subject to assess its clinical advantage. Bianchi procedure is a longitudinal intestinal lengthening and tailoring procedure (LILT) and may be successful in improving absorption and nutritional status but requires multiple anastomoses. Complications of this procedure include fistula formation, anastomotic stenosis, or leakage and sepsis [54]. The 6-year survival rate is 45%, and survivors have residual bowel length greater than 40 cm and no liver disease. The Bianchi procedure is not recommended in neonates with liver disease or intestine length less than 50 cm. The serial transverse enteroplasty procedure (STEP) is a substitute for LILT which increases the girth of bowel. It has a simpler technique that does not need bowel anastomoses, and the tapering can be performed on dilated bowel. STEP increases intestinal length, improves intestinal absorptive capacity, and may decrease the risk of D-lactic acidosis due to bacterial overgrowth. STEP is more favored over other techniques as the weaning from parenteral nutrition is faster and the need for later transplants lesser. There is no difference in early complications, growth rates, or survival between the two procedures, and nearly half of patients operated achieve enteral autonomy, with the median time to wean from parenteral nutrition (PN) being 21 months postoperatively. Patients whose bowel re-dilates after a lengthening procedure have worse overall outcomes. Complications of STEP include gastrointestinal bleeding, staple line leak, hematoma, abscess formation, stricture, pleural effusion, obstruction, a need for transplantation, and even death. In a recent publication, the rate of independence from PN post-STEP was reported as 58% with parenteral calories decreasing from 71 to 36% within 1 month and to 12% after 1 year. The total increase in intestinal length achieved was about 49% [54].

Small bowel transplantation (SBT) may be considered in patients who have progressive, severe, or irreversible intestinal failure with associated liver disease. Other considerations might be a lack of venous access, recurrent life-threatening central venous catheter-associated sepsis, complete mesenteric thrombosis, slow growing tumors of the hepatic hilum or root of mesentery, or extremely short residual bowel with no chance of achieving enteral autonomy in patients who prefer transplantation over lifelong PN dependence [54]. Small bowel transplantation has a 5-year graft survival rate of 48% with lifelong immunosuppressant medications. Types of transplantation include isolated intestine, isolated liver, combined liver and intestine, and multi-visceral. Complications are rejection, infection, graft-versus-host disease, and posttransplant lymphoproliferative disease. Overall, one year patient and intestine graft survival is 89%, being 79% in intestine and 72% in liver-intestine graft recipients. Patient and intestine graft survival falls to 46% by 10 years. At 10 years the survival of intestine only recipients is 29%, whereas, that of liver-intestine recipients 39-42%. More recently, living donor intestinal transplantation has been done successfully in pediatric patients which eliminates waiting time.
