Postoperative complications significantly contribute to prolonged hospital stay, increased healthcare costs, and mortality in surgical patients. Despite advancements in surgical and anesthetic techniques, early recognition of at-risk patients remains a challenge. Traditional risk scores such as ASA and POSSUM are widely used but lack sensitivity in dynamic postoperative settings.

Biomarkers reflecting systemic inflammation, infection, and immune response have emerged as potential tools for predicting complications. CRP and PCT are routinely available markers, while IL-6 and hematological indices such as NLR are gaining clinical importance. However, their collective predictive value in general surgery remains underexplored.

This study investigates the predictive role of selected biomarkers for postoperative complications in a general surgery cohort.

Study Design and Population: A prospective observational study was conducted at a tertiary care center. Adult patients (>18 years) undergoing elective or emergency general surgery between January 2023 and June 2024 were included. Patients with pre-existing sepsis, immunosuppressive therapy, or malignancy were excluded.

Sample Size: 300 patients were enrolled based on power calculation assuming 25% expected complication rate.

Biomarker Assessment: Blood samples were collected preoperatively and on postoperative days 1 and 3. The following biomarkers were analyzed: CRP, PCT, NLR, and IL-6.

Outcome Measures: Primary outcome was occurrence of postoperative complications within 30 days, classified as infectious or non-infectious.

Statistical Analysis: Biomarker levels were compared between groups using t-tests and chi-square tests. Logistic regression identified independent predictors. ROC analysis evaluated discriminatory ability. p<0.05 was significant

Patient Characteristics: Of 300 patients, mean age was 54.2 ± 12.7 years, with male predominance (62%). Elective surgeries accounted for 68%, while 32% were emergency procedures.
Complication Profile: 92 patients (30.6%) developed postoperative complications. Most frequent: surgical site infection (14.6%), sepsis (7.3%), pulmonary (5.3%), cardiovascular (3.3%).

Table 1. Biomarker Findings

Table 2. Baseline Characteristics

Table 3. Multivariate Logistic Regression Predictors

Figures

Figure 1. PRISMA-style flow diagram of patient inclusion and analysis.

Figure 2. Forest plot of odds ratios for biomarkers predicting postoperative complications.

Figure 3. ROC curves comparing predictive performance of biomarkers (PCT, CRP, IL-6, NLR).

Figure 4. Kaplan–Meier complication-free survival curve stratified by PCT levels.

Table 4. Types of Surgeries Performed

Table 5. Distribution of Postoperative Complications

Table 6. Biomarker Cut-off Values and Diagnostic Performance

Table 7. Length of Hospital Stay

Table 8. Postoperative Mortality

Our study demonstrates that biomarkers reflecting systemic inflammation and infection can serve as valuable predictors of postoperative complications in general surgery. Among them, PCT showed the strongest predictive value, particularly for sepsis and infectious complications (1,2,4,5,11). CRP, though less specific, remained reliable when persistently elevated (12–14). NLR independently predicted cardiopulmonary complications (6,7), and IL-6 demonstrated early elevation within 24 hours (8,9). These findings align with prior reports highlighting the role of inflammatory biomarkers in surgical outcomes (1,3,10,15).

These findings suggest that combining traditional risk scores with biomarker monitoring could enhance perioperative assessment. Limitations: single-center study, short 30-day follow-up, lack of long-term outcomes. Future multicenter trials are warranted.

Biomarkers including PCT, CRP, NLR, and IL-6 provide significant predictive value for postoperative complications in general surgery patients. Incorporating biomarker surveillance into perioperative protocols may improve early detection, intervention, and outcomes.

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