European Journal of Cardiovascular Medicine

The period immediately following bowel resection is characterized by a profound shift in metabolic demand. Surgical trauma induces a systemic stress response marked by hypermetabolism, increased protein catabolism, and heightened inflammatory activity [1]. In the absence of timely enteral nutrition, patients experience accelerated lean tissue loss, impaired wound healing, and diminished immune defenses. These factors collectively prolong recovery, increase susceptibility to infectious complications, and extend hospital length of stay, placing a significant burden on both patients and healthcare systems [2].

Traditional postoperative management after intestinal surgery has prioritized “gut rest,” withholding oral intake until clinicians observe objective signs of gastrointestinal (GI) function, typically the return of bowel sounds and passage of flatus [3]. This approach was conceived to minimize mechanical stress on fresh anastomoses and prevent postoperative ileus. However, prolonged fasting further exacerbates gut mucosal atrophy, promotes bacterial translocation from the lumen, and deprives the enterocytes of essential luminal nutrients necessary for barrier maintenance [4]. Moreover, prolonged starvation often necessitates reliance on parenteral nutrition, which carries its own risks of catheter-related infections and metabolic complications.

In contrast, early enteral feeding (EEF) has emerged as a key component of enhanced recovery after surgery (ERAS) protocols. Initiating clear-liquid intake within 24 hours of surgery preserves the structural and functional integrity of the gut mucosa, stimulates the release of gut peptides (such as gastrin, motilin, and cholecystokinin) that promote motility, and supports the gut-associated lymphoid tissue critical for mucosal immunity [5]. Early feeding also confers systemic benefits attenuating the inflammatory response, reducing insulin resistance, and improving nitrogen balance which translate into faster return of GI function, shorter hospital stays, and lower overall morbidity [6].

A growing body of clinical trials and meta-analyses in colorectal and upper GI surgery has demonstrated that EEF can shorten time to first flatus and bowel movement by up to 24 hours, reduce the length of hospitalization by 1–2 days, and decrease rates of postoperative infections without increasing anastomotic leak or aspiration [7]. Yet, heterogeneity in trial designs variations in the timing of feeding, the composition of enteral formulas, and patient selection criteria has limited the universal adoption of EEF. Furthermore, most prior studies have focused on narrow patient groups (e.g., only colorectal resections or exclusively benign disease), leaving uncertainty about EEF’s efficacy across the full spectrum of bowel resections and in a broad adult age range [8].

To address these gaps, our trial prospectively randomizes adults aged 18–60 years undergoing elective small- or large-bowel resection to either early clear-liquid feeding at 24 hours or conventional delayed feeding after clinical evidence of GI recovery. By standardizing feeding protocols, ensuring adequate sample size with a five-year enrollment window, and evaluating a comprehensive set of outcomes including GI recovery metrics, nutritional biomarkers, pain scores, complication rates, readmissions, and patient satisfaction we aim to provide definitive evidence on the safety and efficacy of EEF versus delayed feeding in routine surgical practice.

Aims and Objectives

Aim

To determine whether initiating clear-liquid feeding at 24 hours postoperatively (early enteral feeding) versus delaying oral intake until clinical return of gastrointestinal function improves recovery outcomes in adults aged 18–60 years undergoing elective bowel resection.

Primary Objectives

1. Compare the time to first flatus between early-feeding and delayed-feeding groups.
2. Compare the time to first bowel movement between the two groups.
3. Assess the difference in total postoperative hospital stay between early-feeding and delayed-feeding patients.

Secondary Objectives

1. Evaluate and compare 30-day postoperative complication rates (anastomotic leak, wound infection, pneumonia, ileus) between groups.
2. Measure and contrast serum albumin and prealbumin levels on postoperative day 5 as markers of nutritional recovery.
3. Compare patient-reported pain scores (VAS on postoperative days 1–5) between early- and delayed-feeding cohorts.
4. Determine differences in 30-day readmission rates between the two feeding strategies.
5. Assess patient satisfaction with their feeding regimen at discharge using a standardized Likert scale.
6. Explore whether age subgroup (18–39 vs. 40–60 years) or type of resection (small vs. large bowel) modifies the effect of feeding timing on primary and secondary outcomes.

Study Design and Setting

This single-center, parallel-group, randomized controlled trial was conducted at the Department of General Surgery, Katihar Medical College Hospital, Katihar, Bihar during the period of January 2020 through December 2025. The protocol was approved by the Institutional Ethics Committee (IEC No. XXX/2020) and registered prospectively with the Clinical Trials Registry of India (CTRI/2020/01/012345). All participants provided written informed consent prior to enrollment.

Participants

Inclusion criteria:

• Age 18–60 years.
• Scheduled for elective small- or large-bowel resection with primary anastomosis for benign or malignant indications.
• American Society of Anesthesiologists (ASA) physical status I–III.

Exclusion criteria:

• Emergency or damage-control surgery.
• Pre-existing gastrointestinal motility disorders (e.g., gastroparesis).
• Chronic organ failure (renal dialysis, decompensated liver disease) or immunosuppression.
• Pregnancy or lactation.
• Inability to provide informed consent.

Sample Size Calculation

Based on prior data indicating a mean 1.5-day reduction in hospital stay (standard deviation 3.0 days) with early feeding, 90 patients per arm were required to achieve 80% power at a two-sided α = 0.05. Allowing for a 10% drop-out rate, we planned to enroll 200 patients (100 per group).

Randomization and Allocation Concealment

An independent statistician generated a computer-based randomization sequence with permuted blocks of four, stratified by type of resection (small vs. large bowel). Allocations were sealed in sequentially numbered, opaque envelopes. After skin closure, the circulating nurse opened the envelope to assign the patient to early- or delayed-feeding, ensuring blinding of the surgical team to intraoperative care.

Interventions

• Early-Feeding (EEF) Group:
• Initiation of clear liquids at 24 hours postoperatively if hemodynamically stable and pain controlled.
• Advancement to full liquids on postoperative day (POD) 2 and to soft solids by POD 3–4 as tolerated.
• Delayed-Feeding (DF) Group:
• Nil per os until clinical return of bowel function, defined as presence of bowel sounds in ≥3 quadrants and passage of flatus.
• Upon meeting these criteria, feeding advanced identically to the EEF group.

All patients received standardized ERAS components: multimodal analgesia, thromboprophylaxis, early mobilization, and goal-directed fluid therapy.

Outcome Measures

Primary outcomes:

1. Time to first flatus (hours from end of surgery)
2. Time to first bowel movement (hours from end of surgery)
3. Length of postoperative hospital stay (days)

Secondary outcomes:

• Incidence of complications within 30 days: anastomotic leak, wound infection, pneumonia, and ileus.
• Readmission within 30 days of discharge.
• Nutritional markers on POD 5: serum albumin and prealbumin.
• Patient-reported VAS pain scores on POD 1–5.
• Patient satisfaction with feeding regimen at discharge (5-point Likert scale).

Data Collection and Follow-Up

Trained research staff, blinded to group allocation, recorded perioperative data on case forms. Daily assessments continued until discharge. A follow-up visit or telephone call on POD 30 captured late complications and readmissions.

STATISTICAL ANALYSIS

Continuous variables are reported as mean ± standard deviation or median (IQR) based on distribution. Categorical variables are presented as counts and percentages. Between-group comparisons used Student’s t-test or Mann–Whitney U test for continuous data and χ² or Fisher’s exact test for categorical data. Time-to-event outcomes were further analyzed with Kaplan–Meier curves and log-rank tests. A two-sided p-value < 0.05 denoted statistical significance. Analyses adhered to intention-to-treat principles and were performed.

Quality Assurance

An independent Data Safety Monitoring Board reviewed adverse events biannually. Protocol adherence was audited quarterly, and missing data exceeding 5% for any outcome were addressed via multiple imputation.

A total of 200 patients were randomized equally to Early-Feeding (EEF, n = 100) and Delayed-Feeding (DF, n = 100). Twenty patients (10 %) 10 in each arm withdrew before primary endpoints, yielding 180 evaluable patients (90 per group). Baseline characteristics were well balanced. EEF significantly accelerated gastrointestinal recovery, reduced hospital stay, and improved nutrition and pain scores without increasing complications. Readmissions and patient satisfaction also favored EEF. Subgroup analyses confirmed consistent benefits across age and resection type.

Table 1. Baseline Characteristics of the Analyzed Cohort

Table 1 shows demographics, surgical indications, resection types, and ASA status for the 180 evaluable patients.

Table 2. Gastrointestinal Recovery Metrics

Table 2 compares time to first flatus and first bowel movement between groups.

Table 3. Length of Postoperative Hospital Stay

Table 3 shows total days hospitalized after surgery.

Table 4. Postoperative Complications

Table 4 presents 30-day complication rates in each group.

Table 5. Nutritional Parameters on Postoperative Day 5

Table 5 compares serum protein levels as markers of nutritional recovery.

Table 6. Pain Scores (VAS) on Postoperative Days 1–5

Table 6 shows daily pain assessments, reflecting patient comfort.

Table 7. Readmissions and Patient Satisfaction

Table 7 depicts 30-day readmissions and discharge satisfaction.

Table 8. Subgroup Analysis of Length of Stay

Table 8 shows hospital stay by age and resection type.

Table 1 confirms matching of baseline demographic and clinical characteristics between Early-Feeding and Delayed-Feeding groups. Table 2 demonstrates that Early-Feeding significantly accelerates time to first flatus and bowel movement (both p < 0.001). Table 3 shows a markedly shorter hospital stay with Early-Feeding (6.2 vs. 8.5 days; p < 0.001). Table 4 indicates no significant difference in overall postoperative complications. Table 5 reveals superior nutritional recovery by postoperative day 5 in the Early-Feeding arm. Table 6 highlights reduced pain scores from postoperative day 2 onward. Table 7 suggests a trend toward fewer readmissions and significantly higher patient satisfaction with Early-Feeding. Finally, Table 8 confirms that the benefits of Early-Feeding on hospital stay are consistent across age groups and types of bowel resection.

In this rigorous five-year randomized trial involving 200 adults (18–60 years) undergoing elective bowel resection, we demonstrated that initiating clear-liquid feeding at 24 hours postoperatively (early enteral feeding, EEF) confers substantial recovery advantages over traditional delayed feeding (DF) without compromising patient safety [9]. After accounting for a 10 % attrition (20 withdrawals equally distributed between arms), 180 patients (90 per group) were analyzed, providing the statistical power to detect meaningful differences in gastrointestinal (GI) function, length of hospital stay, nutritional recovery, pain control, and patient-centered outcomes [10].

Acceleration of GI Recovery

EEF led to an 18-hour reduction in time to first flatus (36 ± 12 h vs. 54 ± 16 h) and a 24-hour reduction in time to first bowel movement (60 ± 18 h vs. 84 ± 20 h). These improvements likely reflect the physiologic benefits of early luminal stimulation: enteral nutrients provoke the release of motility-enhancing gastrointestinal hormones, maintain mucosal structure, and support the gut-associated lymphoid tissue that regulates barrier function. By jump-starting peristalsis, EEF helps overcome the postoperative ileus that commonly delays feed tolerance in DF protocols [11,12].

Reduction in Hospital Stay and Resource Use

The enhanced motility translated directly into shorter hospitalization—EEF patients were discharged on average 2.3 days earlier (6.2 ± 1.8 vs. 8.5 ± 2.3 days). A reduction of this magnitude carries significant implications for hospital throughput, bed availability, and overall healthcare costs. When applied across a surgical service, routine EEF could free valuable resources and reduce the financial burden of prolonged admissions [13,14].

Maintenance of Safety Profile

A primary concern with early feeding is potential stress on fresh anastomoses and risk of aspiration. In our study, EEF did not increase the incidence of anastomotic leak (2.2 % vs. 3.3 %), wound infection, pneumonia, or ileus; overall complication rates were statistically equivalent (13.3 % vs. 15.6 %). This safety finding underscores that, with careful patient selection (ASA I–III) and adherence to enhanced-recovery pathways—including multimodal analgesia, goal-directed fluids, and early mobilization EEF can be implemented without elevated surgical risk [15,16].

Improvement in Nutritional Status and Symptom Control

On postoperative day 5, EEF recipients exhibited higher serum albumin (3.8 ± 0.4 vs. 3.4 ± 0.5 g/dL) and prealbumin (18.2 ± 3.1 vs. 15.7 ± 3.4 mg/dL), indicating better protein repletion during the critical early catabolic period. Restoration of nutrition during this window helps preserve lean body mass and supports wound healing and immune function. Pain scores, measured by VAS, were significantly lower in the EEF group from day 2 onward, likely reflecting reduced opioid requirements (as patients tolerate early feeds, analgesia can be more targeted) and quicker resolution of ileus-related discomfort [17,18].

Patient-Centered Outcomes

Beyond physiologic metrics, EEF enhanced the patient experience. Satisfaction at discharge was significantly higher (88.9 % vs. 75.6 %), and although not powered as a primary endpoint, there was a favorable trend in 30-day readmission rates (5.6 % vs. 11.1 %). Improved satisfaction may derive from earlier return to normalcy—eating, mobility, and discharge plans—which contribute to psychological as well as physical well-being [19,20].

Consistency Across Subgroups

Subgroup analyses by age (18–39 vs. 40–60 years) and type of resection (small vs. large bowel) consistently mirrored the overall findings: EEF shortened stay by approximately 2–3 days and did not alter complication rates regardless of patient age or surgical procedure. This broad applicability suggests that EEF protocols can be generalized across diverse adult surgical populations.

Strengths and Limitations

Key strengths include the randomized, stratified design; adequate sample size with dropout allowance; standardized ERAS protocols; and comprehensive outcome assessment encompassing objective, biochemical, and patient-reported measures. Limitations stem from the single-center setting, which may limit extrapolation to institutions without established ERAS programs or in resource-constrained environments. The reliance on serum albumin and prealbumin as nutritional proxies, while practical, does not capture changes in body composition; future studies might incorporate direct measures such as bioimpedance or nitrogen balance. Finally, the balanced 10 % withdrawal rate underscores the importance of sustained patient engagement in prolonged trials.

Clinical Implications

Our findings support updating traditional “nil by mouth” policies to incorporate EEF within 24 hours of bowel resection. Surgeons and perioperative teams should consider revising postoperative order sets to allow clear liquids at 24 hours for appropriately selected patients, with stepwise progression to full diet as tolerated. Implementation of EEF has the potential to accelerate recovery, improve nutrition and comfort, reduce hospital utilization, and enhance patient satisfaction—core goals of modern enhanced recovery pathways.

Future Directions

Further research should evaluate cost-effectiveness analyses of EEF implementation, explore its benefits in higher-risk cohorts (e.g., malnourished or elderly patients), and determine the optimal composition of early feeds (immunonutrition vs. standard formulas). Multi-center collaborations will help validate these results across varied clinical environments and refine best-practice guidelines for postoperative feeding.

In this five-year randomized trial of 200 adults undergoing elective bowel resection, early initiation of clear-liquid feeding at 24 hours postoperatively proved both safe and highly effective. After 10 % attrition (20 withdrawals), 180 patients were analyzed, revealing that early feeding:

• Accelerates gastrointestinal recovery (first flatus 18 h sooner; first bowel movement 24 h sooner)
• Shortens hospital stay by an average of 2.3 days
• Enhances nutritional recovery by postoperative day 5
• Reduces pain from postoperative day 2 onward
• Improves patient satisfaction without increasing complication rates
• Trends toward fewer 30-day readmissions

These findings support incorporating early enteral feeding into standard postoperative protocols for adults aged 18–60 years undergoing bowel resection, aligning with enhanced recovery principles and optimizing both clinical outcomes and patient experience.

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