Joeky Senders

74 Chapter 4 0-7 days of dalteparin; p = 0.24) (Table 2) or 90 days (8.9% versus 4.8%; p = 0.09) (Table 3) (Figure 1). No other risk factors were identified for VTE within 21 days. Patients that developed a VTE within 90 days had a significantly higher BMI compared to patients who did not (28.1±5.8 versus 25.9±4.4 kg/m 2 p = 0.04). In the multivariable analysis including LMWH duration and all variables with a p-value less than 0.20, prolonged prophylaxis was not significantly associated with the rate of VTE within 21 days (Odds Ratio[OR] 2.86; 95% CI 0.53 – 21.45; p = 0.24) or 90 days (OR 2.19; 95% CI 0.88 – 5.75; p = 0.09) after surgery. Additionally, immobility was associated with VTE within 21 days (OR 7.75; 95% CI 1.01 – 43.97; p = 0.02) and 90 days after surgery (OR 4.15; 95% CI 1.15 – 13.03; p = 0.03). High BMI was associated with VTE within 90 days after surgery (OR 1.66 per 5 kg/m 2 increase; 95% CI 1.08 – 1.83; p = 0.02). In the univariable analysis for ICH, prolonged prophylaxis was significantly associated with the occurrence of ICH (5.9% vs 0.6%; p = 0.02) (Table 4). In the multivariable analysis, prolonged prophylaxis was also associated with the occurrence of ICH (OR 9.67; 95% CI 1.73 – 180.95; p = 0.03). No other risk factors for ICH were identified. FIGURE 1. Incidence of venous thromboembolism and intracranial hemorrhage compared by duration of postoperative thromboprophylaxis. Abbreviations: ICH=intracranial haemorrhage; LMWH=low-molecular weight heparin; VTE=venous thromboembolism; VTE21=VTE within 21 days after surgery; VTE90=VTE within 90 days after surgery.