Impact of the Body Mass Index on Hemorrhage After Surgery for Thyroid Cancer

To investigate the effects of different values of the body mass index (BMI) on postoperative hemorrhage (PH) in thyroid cancer (TC) and its clinical management.

This retrospective cohort study selected 43 patients with hemorrhage after TC surgery in 7413 cases. Patients were divided based on the BMI (kg/m²) into normal (24), overweight group (24 ≤BMl<28) and obese (≥28) groups. Clinical and pathologic data, bleeding cause, bleeding site, treatment and prognosis were assessed.

BMI (P=0.038) is an independent risk factor for PH of TC, related to hypertension (P=0.004) and coronary heart disease (P=0.001) in the three groups. Preoperative weight loss was not noted (P=0.477). Hemorrhage in 60.47% of patients occurred between 4 h and 8 h after surgery. The higher the BMI, the longer was the operative time (≥1 h, 65.12%) (P=0.017), which resulted in greater intraoperative blood loss (≥20 mL, 74.42%) (P=0.025), postoperative hypoparathyroidism (P=0.015) and the probability of injury to the recurrent laryngeal nerve (P=0.026). The main causes of bleeding were incomplete vascular ligation (30.23%), severe postoperative cervical activity (16.28%) and long-term use of anticoagulant drugs (11.63%). Overall survival at 5 years in the obese group was poor (P=0.015). Forty patients (93.02%) underwent surgical exploration and hemostasis and two patients (4.65%) underwent tracheotomy. All PH complications disappeared completely after active postoperative treatment, and all patients were discharged from hospital.

Obesity is closely associated with PH in TC patients. Therefore, in obese patients, active prevention preoperatively, complete hemostasis intraoperatively, early detection and timely treatment postoperatively are the key factors to reduce PH risk.