Introduction

Postoperative complications following abdominal surgery remain a significant global health concern because they contribute substantially to patient morbidity, mortality, prolonged hospitalization, increased healthcare costs, and reduced quality of life. Despite advances in surgical techniques, anesthesia, infection prevention, and perioperative care, postoperative complications continue to occur in approximately 15–30% of patients undergoing major abdominal surgery, depending on patient characteristics, procedure type, and healthcare setting [1,2].

Abdominal surgery includes a broad range of elective and emergency procedures involving the gastrointestinal tract, hepatobiliary system, abdominal wall, and other intra-abdominal organs. Although these operations are frequently lifesaving, they expose patients to numerous postoperative complications, including wound infection, postoperative ileus, respiratory complications, thromboembolic events, bleeding, cardiovascular complications, and psychological disturbances. These adverse events can delay recovery, prolong hospital stay, increase readmission rates, and negatively affect long-term health outcomes [3,4].

The occurrence of postoperative complications is multifactorial. Patient-related factors such as advanced age, obesity, smoking, diabetes mellitus, hypertension, cardiovascular disease, previous abdominal surgery, and other chronic comorbidities have consistently been identified as major predictors of poor postoperative outcomes. These factors impair immune function, delay wound healing, reduce physiological reserve, and increase susceptibility to infection and other postoperative adverse events [5–8].

Similarly, several surgical-related factors influence postoperative recovery. Emergency surgery, prolonged operative duration, open laparotomy, extensive surgical incisions, greater intraoperative tissue trauma, and certain anesthetic techniques have all been associated with increased postoperative morbidity. Conversely, minimally invasive surgical approaches, shorter operative times, and optimized perioperative management have been shown to reduce complication rates and improve patient recovery [9–12].

Early recognition of patients at increased risk enables surgeons, anesthesiologists, and nurses to implement evidence-based preventive interventions. Nursing surveillance during the postoperative period is particularly important for detecting early signs of gastrointestinal dysfunction, respiratory compromise, wound infection, thromboembolic complications, and psychological distress. Comprehensive postoperative assessment and multidisciplinary care are therefore essential to improving patient safety and surgical outcomes [13,14].

Although numerous studies have examined postoperative complications worldwide, evidence from Iraq, particularly the Kurdistan Region, remains scarce. Furthermore, little information is available regarding the incidence and determinants of postoperative abdominal surgery complications at Raniya Teaching Hospital. Generating local evidence is essential for identifying context-specific risk factors and supporting quality improvement initiatives aimed at reducing postoperative morbidity. Therefore, this study aimed to determine the incidence of postoperative complications following abdominal surgery and examine their association with sociodemographic characteristics and surgery-related factors among patients undergoing abdominal surgery at Raniya Teaching Hospital.

Materials and Methods

Study Design

A hospital-based quantitative cross-sectional study was conducted to assess postoperative complications following abdominal surgery and identify their associations with patients' sociodemographic and surgical-related characteristics. This design was considered appropriate for estimating the incidence of postoperative complications and examining the relationships between potential risk factors and postoperative outcomes.

Study Setting and Period

The study was carried out in the General Surgery Ward of Raniya Teaching Hospital, Raparin Administration, Sulaymaniyah Governorate, Iraq. Data collection was conducted over four months, from 3 November 2024 to 2 February 2025.

Study Population and Sample

The study population consisted of adult patients admitted to the General Surgery Ward who underwent abdominal surgery during the study period. A non-probability purposive sampling technique was employed to recruit eligible participants. The required sample size was calculated using the population proportion formula:

n=Z2P(1−P)d2n=\frac{Z^{2}P(1-P)}{d^{2}}n=d2Z2P(1−P)​

where Z = 1.96 (95% confidence interval), P = 0.53, q = 1 − P, and d = 0.05, yielding a minimum required sample of 204 patients, all of whom were included in the study.

Eligibility Criteria

Inclusion criteria

• Adult patients (≥18 years) undergoing elective or emergency abdominal surgery.
• Patients admitted to the General Surgery Ward during the study period.
• Patients willing to participate and who provided informed consent.

Exclusion criteria

• Patients who declined participation.
• Patients discharged before postoperative assessment could be completed.
• Patients with incomplete clinical information or missing postoperative follow-up data.

Data Collection Instrument

Data were collected using a researcher-developed structured questionnaire based on an extensive review of the relevant literature. The instrument was evaluated for content validity by a panel of 17 experts, and demonstrated acceptable internal consistency with a Cronbach's alpha coefficient of 0.78.

The questionnaire consisted of three sections:

1. Sociodemographic characteristics: age, sex, residence, educational level, body mass index (BMI), smoking status, and comorbidities.
2. Surgical profile: previous surgical history, time since previous surgery, surgical site, duration of surgery, type of surgery (elective or emergency), surgical procedure, operative approach (laparotomy or laparoscopy), incision length, anesthesia type, and medication history.
3. Postoperative complications: assessment of mechanical complications, paralytic ileus, gastrointestinal complications, cardiovascular complications, respiratory complications, wound complications, infectious complications, thrombotic complications, hematoma, bleeding, postoperative pain, nausea, vomiting, constipation, anorexia, abdominal distension, anxiety, and psychological complications.

Data Collection Procedure

Eligible patients were identified after admission to the General Surgery Ward. Following written informed consent, participants were interviewed face-to-face using the structured questionnaire. Additional clinical information, including medical history, operative details, laboratory investigations, surgeons' notes, and nursing documentation, was extracted from patients' medical records. Patients were monitored throughout the postoperative period, and any complications that developed before discharge were documented.

Statistical Analysis

Data were entered, coded, cleaned, and analyzed using the Statistical Package for the Social Sciences (SPSS). Descriptive statistics, including frequencies, percentages, means, and standard deviations, were used to summarize participant characteristics and postoperative complications. Associations between postoperative complications and independent variables were examined using Spearman's rank correlation coefficient. Statistical significance was established at p < 0.05, while p < 0.01 was considered highly significant.

Ethical Considerations

Ethical approval was obtained from the appropriate Institutional Review Board before commencement of the study. Official permission to conduct the research was granted by the College of Nursing, University of Raparin, and the Raparin General Directorate of Health. Participation was voluntary, written informed consent was obtained from all participants, confidentiality and anonymity were maintained throughout the study, and all procedures complied with the ethical principles of the Declaration of Helsinki.

Results

A total of 204 patients who underwent abdominal surgery were included in the study. Their sociodemographic characteristics, surgical profiles, and postoperative complications were analyzed to determine the incidence of complications and their associations with patient- and surgery-related factors.

Sociodemographic Characteristics

The largest proportion of participants (47.5%) were aged 34–49 years, followed by 25.0% aged 50–65 years, while only 9.3% were 66–81 years. Males accounted for 56.9% of the study population. Most participants resided in urban areas (87.7%). Regarding educational level, 35.8% were illiterate, 26.5% had primary education, 19.6% had secondary education, and 18.1% had completed university education or higher. One-third of participants had a normal body mass index (33.3%), another one-third were overweight (33.3%), whereas 20.6% were underweight and 12.7% were obese. The majority (79.4%) were non-smokers, and 78.4% had no documented comorbidities. Among those with chronic illnesses, hypertension (8.8%) was the most common, followed by diabetes mellitus (3.9%), other diseases (3.9%), COVID-19 (2.9%), and heart disease (2.0%) (Table 1).

Surgical Profile

Most participants (62.7%) had no previous history of abdominal surgery, while 32.8% had undergone one previous operation and 4.4% had undergone multiple previous surgeries. Among patients with previous operations, 30.9% had their last surgery more than two years before the current admission. The right lower quadrant was the most frequent surgical site (53.9%), followed by the left lower quadrant (21.6%) and right upper quadrant (17.2%). More than half of the procedures (54.4%) lasted less than 30 minutes, whereas only 8.3% exceeded 60 minutes. Elective surgeries represented 59.8% of procedures, while emergency surgeries accounted for 40.2%. Hernia repair (37.7%) and appendectomy (36.3%) were the most common procedures. Most operations were performed through laparotomy (90.7%), and 63.7% involved medium-sized incisions (7.5–15 cm). General anesthesia was administered in 68.6% of cases, and 92.2% of participants reported no history of medication use before surgery (Table 2).

Association Between Surgical Factors and Postoperative Complications

Correlation analysis demonstrated significant associations between several surgical characteristics and postoperative complications (Table 3). Previous surgical history was positively associated with abdominal distension, paralytic ileus, functional complications, and mechanical complications. Longer operative duration was significantly associated with hematoma formation and postoperative bleeding. Emergency surgery was significantly correlated with thrombotic and infectious complications. Laparotomy was associated with higher rates of mechanical complications and paralytic ileus compared with laparoscopy. Longer surgical incisions were significantly related to gastrointestinal and mechanical complications, while the use of general anesthesia was associated with postoperative nausea and mechanical complications. Furthermore, medication history showed significant positive correlations with cardiovascular, respiratory, infectious, thrombotic, and psychological complications (all p < 0.05) (Table 3).

Association Between Sociodemographic Characteristics and Postoperative Complications

Table 4 demonstrates significant relationships between sociodemographic variables and postoperative complications. Increasing age was significantly associated with abdominal distension, paralytic ileus, and functional complications, whereas older age showed negative correlations with hematoma and postoperative bleeding. Higher body mass index was significantly associated with bleeding, abdominal distension, and paralytic ileus. Smoking status demonstrated significant positive relationships with abdominal distension and postoperative bleeding. Patients with comorbidities experienced significantly higher rates of abdominal distension, postoperative bleeding, paralytic ileus, and wound complications. Male sex and lower educational level were also associated with selected postoperative complications. These findings indicate that both patient-related and surgical factors contribute significantly to the development of postoperative complications following abdominal surgery (p < 0.05) (Table 4).

Overall Incidence of Postoperative Complications

The overall incidence of postoperative complications among patients undergoing abdominal surgery was 21%. The observed complications included mechanical complications, paralytic ileus, gastrointestinal dysfunction, wound complications, respiratory complications, thrombotic events, cardiovascular complications, psychological complications, postoperative pain, abdominal distension, nausea, vomiting, hematoma, bleeding, constipation, anorexia, and anxiety. The findings indicate that postoperative complications were significantly associated with both surgical characteristics and patients' sociodemographic profiles.

Table 1. Sociodemographic Characteristics of the Participants (N = 204)

Table 2. Surgical Characteristics of the Participants (N = 204)

Table 3. Significant Associations Between Surgical Factors and Postoperative Complications

Spearman's rank correlation coefficient was used to examine associations.

Table 4. Significant Associations Between Sociodemographic Characteristics and Postoperative Complications

Spearman's rank correlation coefficient was used for all analyses

Discussion

The present study investigated the incidence of postoperative complications following abdominal surgery and explored their associations with sociodemographic and surgical-related factors among patients treated at Raniya Teaching Hospital. The findings revealed that 21% of patients experienced one or more postoperative complications, indicating that postoperative morbidity remains an important clinical concern despite advances in perioperative care. The observed complication rate is consistent with reports from other low- and middle-income countries, where postoperative complication rates following abdominal surgery range between 15% and 30% depending on patient characteristics, operative complexity, and healthcare resources [1,2].

The study demonstrated that previous surgical history, duration of surgery, emergency procedures, operative approach, incision length, anesthesia type, and medication history were significantly associated with postoperative complications. Patients with a history of previous abdominal surgery were more likely to develop abdominal distension, paralytic ileus, and mechanical complications. This finding is biologically plausible because repeated abdominal operations frequently result in intra-abdominal adhesions that increase operative difficulty and postoperative bowel dysfunction. Similar findings have been reported by Li et al., who described previous abdominal surgery as an important predictor of postoperative complications because of altered anatomical structures and increased technical challenges during surgery [3].

Operative duration also emerged as an important determinant of postoperative outcomes. Longer surgical procedures were significantly associated with postoperative hematoma and bleeding. Prolonged operative time may reflect increased surgical complexity and greater tissue manipulation, leading to increased blood loss, prolonged anesthesia exposure, and impaired tissue perfusion. These findings agree with the systematic review by Cheng et al., which concluded that longer operative duration independently increases the risk of postoperative complications across various surgical specialties [4].

Emergency surgery demonstrated a significant association with infectious and thrombotic complications. Patients undergoing emergency procedures generally have inadequate preoperative optimization, more severe disease, and limited preparation time compared with elective surgical patients. Consequently, emergency operations are consistently associated with poorer postoperative outcomes. This observation is consistent with previous studies demonstrating significantly higher complication rates after emergency laparotomy than after elective abdominal surgery [5].

The present study further found that laparotomy was associated with significantly higher rates of mechanical complications and paralytic ileus than laparoscopic surgery. Open abdominal surgery produces greater tissue trauma, larger incisions, and increased inflammatory responses, which may delay gastrointestinal recovery and increase postoperative pain. Likewise, longer surgical incisions were associated with gastrointestinal and mechanical complications. These findings support previous evidence indicating that minimally invasive surgical techniques reduce postoperative morbidity by limiting tissue injury and promoting faster recovery [6,7].

An additional finding was the significant association between general anesthesia and postoperative nausea as well as mechanical complications. General anesthesia has been associated with delayed gastrointestinal motility and increased postoperative nausea and vomiting, whereas regional anesthesia may facilitate earlier postoperative recovery through reduced opioid requirements and improved gastrointestinal function. Similar conclusions were reported by Li et al., who demonstrated lower postoperative complication rates among patients receiving combined epidural-general anesthesia compared with general anesthesia alone [8].

Medication history was another significant predictor of postoperative complications. Patients receiving anticoagulants, corticosteroids, or other medications experienced higher frequencies of cardiovascular, respiratory, infectious, thrombotic, and psychological complications. Anticoagulants increase bleeding risk, whereas corticosteroids suppress immune function and delay wound healing, thereby increasing susceptibility to postoperative infection. These findings are consistent with previous literature emphasizing careful preoperative medication assessment and optimization to reduce postoperative adverse events [9].

The present study also demonstrated that several sociodemographic characteristics significantly influenced postoperative outcomes. Advanced age was associated with abdominal distension and paralytic ileus, reflecting age-related physiological decline, impaired gastrointestinal motility, and reduced physiological reserve. Body mass index, smoking status, and pre-existing comorbidities were likewise associated with several postoperative complications, including bleeding, wound complications, and gastrointestinal dysfunction. These findings are consistent with numerous previous studies identifying obesity, smoking, diabetes, hypertension, and cardiovascular disease as important risk factors for postoperative morbidity [10–12].

From a nursing perspective, these findings emphasize the importance of comprehensive preoperative risk assessment and vigilant postoperative monitoring. Nurses play a central role in identifying patients at increased risk, promoting early mobilization, encouraging pulmonary hygiene, monitoring wound healing, assessing gastrointestinal function, and recognizing early signs of complications. Implementation of standardized postoperative nursing protocols and multidisciplinary perioperative care pathways may substantially reduce complication rates and improve patient outcomes.

Although this study provides valuable evidence regarding postoperative complications in a regional teaching hospital, several limitations should be acknowledged. The cross-sectional design precludes causal inference between risk factors and postoperative complications. The use of purposive sampling and recruitment from a single hospital may limit the generalizability of the findings to other healthcare settings. Additionally, postoperative outcomes were evaluated only during hospitalization; therefore, complications occurring after discharge were not captured. Future multicenter prospective cohort studies with longer follow-up periods are recommended to validate these findings and establish causal relationships between perioperative risk factors and postoperative outcomes.