Defecation delay in patients after lung tumor surgery: a prospective nested case-control study

BACKGROUND: Defecation delay (greater than or equal to 3 days post-surgery) is a common symptom in patients after lung tumor surgery. This study investigated the incidence and relevant risk factors of defecation delay in patients after lung tumor surgery. METHODS: Between October 2019 and March 2020, a prospective nested case-control study was conducted in 80 patients who received lung tumor surgery in the Department of Thoracic Surgery at the Sun Yat-sen University Cancer Center. According to the Rome III criteria for functional constipation and the accepted definitions in the literature, patients with defecation delay time greater than or equal to 3 days post-surgery were classified as the defecation delay group, and the remaining patients were considered the control group. A questionnaire survey was conducted to explore the trait of the stool, defecation time, postoperative activity, diet, and perioperative pain score. Statistical analyses were performed to compare the risk factors affecting defecation time in the two groups. RESULTS: Out of 80 patients, a total of 44 patients (44/80) experienced defecation delay after the operation. Univariate analysis showed that there were significant differences between the two groups in operation methods (P<0.029), postoperative stool trait (P<0.001), difficulty in defecation (P<0.01), and perioperative pain score (P=0.0178), suggesting that change of stool characteristics and pain were possible factors causing defecation delay. Multivariate analysis also revealed significant differences between the two groups in the postoperative pain score on the first day post-surgery (P=0.03). CONCLUSIONS: Defecation delay is a common symptom in patients after lung cancer surgery, and is related to operation method, pain score, and changes in stool characteristics. This study identified that minimally invasive surgery, postoperative pain relief treatment, and health education may play an important role in preventing delayed defecation.