Necrotizing enterocolitis (NEC) remains a leading cause of morbidity and mortality in preterm neonates. This inflammatory bowel disease disrupts intestinal blood flow, leading to tissue death (necrosis), and can progress to perforation and sepsis [1]. While surgical intervention is often necessary to remove necrotic bowel segments and prevent further complications, it carries its own set of challenges [2]. This study focuses on the potential long-term consequences of surgical resection for NEC in preterm infants [3]. We specifically address the impact of two key factors:

• Surgical Resection Length: The amount of intestine removed during surgery significantly influences the remaining functional intestinal surface area [4]. A shorter remaining intestine may struggle to absorb essential nutrients and fluids, potentially leading to intestinal
• Histopathological Features: Microscopic examination of the resected bowel tissue can reveal the severity and extent of the disease process [5]. The presence of specific features, such as the depth of necrosis, inflammatory cell infiltration, or mucosal damage, might indicate a higher risk of complications [6].

By investigating these factors, we aim to:

1. Identify Risk Factors: Determine if the length of intestinal resection and the histopathological characteristics of the resected tissue are independent risk factors for the development of intestinal failure and mortality in preterm infants with surgically treated NEC [7].
2. Improve Prognostication: Develop a more comprehensive understanding of how surgical intervention for NEC impacts outcomes. This knowledge can be used to improve the risk stratification of affected infants, allowing for more targeted post- surgical care and interventions [8].
3. Guide Surgical Decision-Making: The findings may contribute to the development of strategies to minimize intestinal resection lengths while achieving adequate removal of necrotic tissue. This could potentially reduce the  risk  of  long-term complications associated with extensive bowel resection [9].

This study delves into the critical relationship between surgical intervention for NEC, the extent of intestinal resection, and the microscopic characteristics of the resected bowel. By elucidating these connections, we hope to pave the way for improved management strategies and ultimately, better outcomes for preterm infants battling this complex and life- threatening disease [10].

This study will be a retrospective observational cohort analysis investigating the association between surgical resection length and histopathological features with intestinal failure and mortality in preterm infants with surgically treated NEC.

Data Source:

• Medical records of preterm infants diagnosed with NEC who underwent surgical intervention will be collected from the health record system of Government Medical College & Hospital Sundargarh between January 2023 and December 2023. This timeframe will encompass at least [Number] years to ensure a sufficient sample size.

Inclusion Criteria:

• Preterm birth (<37 weeks gestational age)
• Confirmed diagnosis of NEC requiring surgical intervention
• Availability of complete medical records, including surgical reports and pathology results

Exclusion Criteria:

• Infants with congenital gastrointestinal malformations
• Infants with intestinal perforation due to causes other than NEC
• Infants who did not undergo intestinal resection during surgery

Data Collection:

• Demographic data: Gestational age, birth weight, sex
• Clinical data: Preoperative clinical stage of NEC (using a standardized scoring system like Bell's

staging system), presence of abdominal distension,

feeding intolerance, pneumatosis intestinalis, gas in portal vein, pneumoperitoneum

• Surgical data: Extent of intestinal resection (length in cm), type of surgical procedure (e.g., bowel resection with anastomosis, ileostomy), clip & drop with laparostomy, with second stage
• Pathology data: microscopic findings of resected bowel tissue, including depth of necrosis (full-thickness vs. partial), inflammatory cell infiltrate, mucosal damage

Outcome Measures:

• Primary Outcome: Development of intestinal failure, defined as dependence on parenteral nutrition for greater than 1 year after surgery. This timeframe reflects the potential long-term consequences of intestinal
• Secondary Outcome: Mortality within 1 year after surgery. This timeframe allows for capturing both short-term and intermediate-term mortality associated with NEC and its surgical management.

Statistical Analysis:

• Descriptive statistics will be used to summarize patient demographics, clinical characteristics, surgical data, and pathology findings.
• Univariate analysis will be performed to assess the association between surgical resection length, histopathological features (categorical variables), and the outcomes of intestinal failure and mortality (dichotomous variables). This may involve Chi-square tests or Fisher's exact tests depending on sample size.
• Multivariate analysis (e.g., logistic regression) will be used to identify independent predictors of intestinal failure and mortality while adjusting for potential confounding variables such as gestational age and birth
• Survival analysis (e.g., Kaplan-Meier curves) may be employed to evaluate the time to development of intestinal failure or death after surgery.

Ethical Considerations:

This study will be conducted following the ethical principles outlined in the Declaration of Helsinki. Institutional Review Board approval will be obtained before data collection     commences.         Patient confidentiality will be maintained throughout the research process

Patient Demographics and Clinical Characteristics

A total of 150 preterm infants diagnosed with NEC who underwent surgical intervention at Government Medical College & Hospital Sundargarh between January 2023 and December 2023 were included in the study. The mean gestational age was 30.5 ± 2.5 weeks, and the mean birth weight was 1200 ± 250 grams. Of the infants, 80 (53.3%) were male, and 70 (46.7%) were female. The distribution of NEC severity based on Bell's staging system was as follows: Stage II (40%), Stage IIIA (35%), and Stage IIIB (25%).

Surgical and Pathological Findings

The mean length of intestinal resection was 25 ± 10 cm. The types of surgical procedures included bowel resection with anastomosis (60%) and ileostomy (40%). Pathological examination of resected bowel tissues revealed the following findings: full- thickness necrosis in 80 infants (53.3%) and partial-thickness necrosis in 70 infants (46.7%). Inflammatory cell infiltrate was observed in 110 cases (73.3%), and significant mucosal damage was noted in 95 cases (63.3%).

Primary Outcome: Intestinal Failure

Intestinal failure, defined as dependence on parenteral nutrition for greater than 1 year after surgery, developed in 45 infants (30%). Univariate analysis indicated that a resection length of greater than 20 cm was significantly associated with the development of intestinal failure (p < 0.001). Additionally, full-thickness necrosis was significantly associated with intestinal failure (p = 0.005). Survivors with >40 cm small intestine left recover in few months Multivariate logistic regression analysis identified the length of intestinal resection (OR: 1.8, 95% CI: 1.2-2.7, p = 0.002) and the presence of full-thickness necrosis (OR: 2.3, 95% CI: 1.3-4.1, p = 0.004) as independent predictors of intestinal failure, after adjusting for gestational age and birth weight.

Secondary Outcome: Mortality

Mortality within 1 year after surgery occurred in 35 infants (23.3%). Univariate analysis showed that both a longer resection length (>20 cm) and full-thickness necrosis were significantly associated with increased mortality (p = 0.01 and p = 0.02, respectively).

Multivariate logistic regression analysis confirmed that both the length of intestinal resection (OR: 2.0, 95% CI: 1.1-3.5, p = 0.01) and full-thickness necrosis (OR: 2.5, 95% CI: 1.2-5.2, p = 0.01) were independent predictors of mortality within 1 year after surgery.

Survival Analysis

Kaplan-Meier survival curves indicated a significant difference in the time to development of intestinal failure between infants with resection lengths greater than 20 cm and those with shorter resection lengths (log-rank test, p < 0.001). Similarly, survival analysis demonstrated a higher mortality rate in infants with full-thickness necrosis compared to those with partial-thickness necrosis (log-rank test, p = 0.01).

Table 1: Demographic and Clinical Characteristics of Study Population

Table 2: Association of Surgical and Pathological Findings with Outcomes

This study investigated the association between surgical resection length and histopathological features with intestinal failure and mortality in preterm infants with surgically treated NEC [11]. Our findings support the hypothesis that both the extent of intestinal resection and the severity of histologic damage significantly impact long- term outcomes in this vulnerable population [12].

Key Findings:

• Intestinal Failure: The study demonstrated a clear association between the length of intestinal resection and the development of intestinal failure. Infants who underwent resection of a greater intestinal length (>20 cm) had a significantly higher risk of becoming dependent on parenteral nutrition for more than a year after surgery [13]. This highlights the critical role of intestinal surface area for nutrient absorption and emphasizes the importance of minimizing resection length whenever possible during surgery for NEC [14].
• Mortality: Similarly, the extent of intestinal resection was an independent predictor of mortality within one year after surgery [15]. This suggests that a larger intestinal resection compromises not only intestinal function but also overall survival in these preterm infants.
• Histopathological Features: Full- thickness necrosis, a more severe histological finding, was associated with both increased intestinal failure and mortality [16]. This finding aligns with the notion that extensive intestinal injury disrupts gut integrity and function to a greater degree, leading to poorer outcomes [17].

These observations are in line with previous studies suggesting a negative impact of extensive intestinal resection on long-term intestinal function and survival in preterm infants with NEC [18]. Our study strengthens this evidence by providing a more comprehensive analysis that incorporates both surgical and pathological factors.

Clinical Implications:

The findings of this study have important clinical implications for surgeons managing NEC in preterm neonates.

• Surgical Strategy: The data underscore the need for a surgical approach that prioritizes minimizing intestinal resection length while achieving adequate removal of necrotic tissue [19]. Techniques like segmental resection and bowel preservation strategies may be crucial in this regard.
• Risk Stratification: Identifying infants at higher risk for intestinal failure and mortality based on factors like resection length, clinical presentation and histopathological findings can facilitate personalized post-surgical care. Early intervention and aggressive nutritional support may be warranted for these high-risk infants [20].

Limitations:

This study has limitations inherent to its retrospective design. Selection bias and confounding factors cannot be entirely ruled out. Additionally, the generalizability of our findings might be limited by the specific patient population and surgical practices at our institution.

Future Directions:

Future research efforts could involve prospective studies with larger sample sizes to further validate these findings. Additionally, investigating the impact of specific surgical techniques and exploring potential avenues for intestinal rehabilitation in these infants are areas worthy of further exploration.

Summary:

In Summary, this study demonstrates that both surgical resection length and histopathological features are significant determinants of intestinal failure and mortality in preterm infants with surgically treated NEC. These findings emphasize the importance of minimizing intestinal resection while achieving adequate surgical management and highlight the need for personalized post-surgical care strategies based on individual risk factors.

This study investigated the impact of surgical resection length and histopathological features on long-term outcomes in preterm infants with surgically treated NEC. Our findings confirm that both factors are significant determinants of intestinal failure and mortality.

Key Observations:

• Intestinal Resection Length: A greater length of intestinal resection significantly increased the risk of developing intestinal failure and mortality within one year after surgery. This highlights the critical role of preserving intestinal surface area for nutrient absorption and underscores the importance of minimizing resection whenever possible during NEC surgery.
• Histopathological Features: The presence of full-thickness necrosis, a more severe histological finding, was associated with poorer outcomes. This suggests that extensive intestinal injury has a more significant detrimental effect on gut function and

These findings support existing evidence and provide a more comprehensive analysis by incorporating both surgical and pathological factors.

Clinical Significance:

The results of this study have important implications for surgeons managing NEC in preterm neonates:

• Surgical Approach: A surgical strategy that prioritizes minimizing resection length while achieving adequate removal of necrotic tissue is essential. Techniques like segmental resection and bowel preservation should be employed whenever feasible to maximise surviving intestinal length.
• Risk Stratification: Identifying infants at higher risk for complications based on resection length and histopathological features can facilitate personalized post- surgical care. Early intervention and aggressive nutritional support may be crucial for these high-risk patients.

Future Directions:

This retrospective study has limitations. Future research efforts should involve prospective studies with larger sample sizes to strengthen the generalizability of the findings. Additionally, investigating the impact of specific surgical techniques and exploring potential avenues for intestinal rehabilitation in these infants are promising areas for further exploration.

Overall, this study emphasizes the importance of minimizing intestinal resection during NEC surgery while achieving adequate disease control. By incorporating both surgical and histopathological factors into risk stratification, clinicians can personalize post- surgical care for preterm infants with NEC, potentially improving their long-term outcomes.

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