Incidence of Venous Thromboembolism in Rhinoplasty

Venous thromboembolism (VTE) is defined by deep venous thrombosis (DVT) with or without pulmonary embolism (PE). It affects up to 200,000 Americans every year.1 In the absence of a specific study addressing the incidence of VTE in rhinoplasty, it is difficult to justify not administering thromboprophylaxis to these patients as surgery is a major risk factor for VTE. However, chemoprophylaxis is not without risk, especially in rhinoplasty where bleeding can carry significant functional and cosmetic consequences. The objective of the present letter is to evaluate the incidence of VTE in cosmetic and functional rhinoplasty over a 5-year period in a single institution in order to precisely establish its value for future reference. After obtaining approval from the Stanford Institutional Review Board, we have retrospectively identified all consecutive rhinoplasty cases (with or without septoplasty) performed by the senior author (S.P.M.) from January 1, 2010 to December 31, 2014. For each patient, age, body mass index (BMI), and surgery duration in minutes were recorded. Intraoperative mechanical VTE prophylaxis with sequential compressive devices (SCDs) was used in all patients. The Caprini score is a risk assessment model consisting of about 40 risk factors, each of which is given a relative risk score of 1 to 5, with increasing scores representing a higher risk of VTE,2 and this score was recorded for each patient during chart review. Finally, for each patient, the presence or not of VTE up to 30 days after discharge was recorded. The definition of VTE was the identification of clinically evident DVT and/or PE that was proven on diagnostic testing. Descriptive statistical analyses were used in order to establish the incidence of VTE in this patient population. The 95% confidence interval (95% CI) for the incidence of VTE was calculated using the Newcombe procedure without continuity correction. A total of 412 patients (207 female, 205 male) were identified during our observation period. All underwent rhinoplasty under general anesthesia. The mean age was 37.5 years (range, 20-75 years), the mean BMI was 25 kg/m2 (range, 19-45 kg/m2), and the mean surgery duration was 156 minutes (range, 27-264 minutes). The median Caprini score was 3 (range, 1-8). There were no identified cases of DVT or PE in our patient population. The incidence of VTE was calculated as 0.0% (95% CI, 0.0%-0.92%). Risk factors are broken down in Table 1. Figure 1 shows that we have a low-risk cohort. Caprini Score Risk Factor Distribution, With Points Attributed to Each, Among Our Rhinoplasty Population (n = 412) Caprini Score Risk Factor Distribution, With Points Attributed to Each, Among Our Rhinoplasty Population (n = 412) Distribution of Caprini scores within our rhinoplasty population (n = 412). The present letter the first study to specifically attempt to estimate the incidence of VTE in rhinoplasty patients. Our finding of 0.0% (95% CI, 0.0%-0.92%) puts rhinoplasty patients in the low to very low-risk categories as defined by the American College of Chest Physicians, and for which chemoprophylaxis is not recommended, based on general surgery data.1 This is confirmed by a recent systematic review of plastic surgery patients for which chemoprophylaxis is not recommended for low-risk patients.3 We believe that the low VTE risk profile of rhinoplasty patients is inherent to both the patient population (young, lean) and the nature of the surgery (early ambulation, outpatient procedure). A median Caprini score of 3.0 was found in our patient population. A score of 3 to 4, according to the initial publication by Caprini,2 puts patients in a high-risk category, and could warrant chemoprophylaxis. This has been disputed in plastic surgery literature that recommends chemoprophylaxis in patients with scores of 8 or higher.4,5 We have not identified a single other study specifically addressing the issue of incidence of VTE in rhinoplasty patients. This makes our findings novel and may serve as future reference for comparison should other investigators decide to further research this issue. In our study, variability was minimized by including cases performed by a single surgeon. A recent database study identified one case of VTE among a subset of 3608 rhinoplasty patients, in the context of a series of 129,007 cosmetic surgery patients.6 This is also in line with the very low incidence of VTE in facelift patients (0.3%) based on a series of 630 patients.7 Our study however has the advantage of showing a single-surgeon experience in consecutively evaluated patients, and we have included both functional and cosmetic cases. A final strength of our study is that Caprini scores were calculated for all patients. A larger study would be required in order to ascertain the exact incidence of VTE in the rhinoplasty population. The confidence interval will be narrowed further with a larger number of patients in subsequent studies. In conclusion, we have identified the incidence of VTE in rhinoplasty patients as 0.0% (95% CI, 0.0%-0.92%). With a theoretical risk of increased bleeding with VTE chemoprophylaxis, we recommend withholding such medication in patients undergoing rhinoplasty. Early ambulation and SCDs suffice to reduce VTE complications to a minimum in this population. The authors declared no potential conflicts of interest with respect to the research, authorship, and publication of this article. The authors received no financial support for the research, authorship, and publication of this article.