Date of Award

January 2022

Document Type

Open Access Thesis

Degree Name

Medical Doctor (MD)



First Advisor

Jonathan N. Grauer


Venous thromboembolism (VTE, including deep venous thrombosis and pulmonary embolism) was studied in children undergoing surgery in general, and those specifically undergoing orthopaedic surgery. Due to the low overall incidence of VTE in this population, VTE chemoprophylaxis is not routinely recommended. However, understanding and quantifying risk factors can help define the risk/benefit considerations of these practices.

The study populations were identified from 2012-2016 National Surgical Quality Improvement Project Pediatric (NSQIP-P) database. Patient demographics, comorbidity factors, and 30-day postoperative outcomes were defined. The populations were then dichotomized into those that did and not have VTE diagnosed in the first 30 postoperative days. In multivariate analysis, patient and surgical factors were controlled for to identify independent risk factors for VTE.

For the overall pediatric surgical population, 361,384 patients were identified, of which VTE was diagnosed in 378 (0.10%). Predictors of VTE in the pediatric surgical population were found to be: American Society of Anesthesiologists (ASA) class of II or greater, age 16-18 years old, non-elective surgery, general surgery (compared to several other surgical specialties), cardiothoracic surgery, and longer operative time (p<0.001 for each comparison). Further, most adverse events investigated were associated with increased risk of subsequent VTE (p<0.001).

For the orthopaedic-specific study, (2) Of 81,490 pediatric orthopaedic surgical patients, 60 (0.07%) were identified as experiencing postoperative VTE. Predictors of VTE in pediatric orthopaedic surgical population were found to be: age 16-18 years (p = 0.002; compared to ages 11-15), ASA class III-V (p = 0.003; compared to ASA class I-II), preoperative blood transfusion (p < 0.001), arthrotomy (p < 0.001), and femur fracture (p < 0.001). Further, any adverse event, major adverse events, minor adverse events, reoperation, and readmission were found to be associated with increased risk of subsequent VTE (p < 0.001 for each category of adverse outcome).

The overall incidence of VTE in the postoperative pediatric population and orthopaedic population was found to be 0.10% and 0.07%, respectively. For both cohorts, defined patient, surgical, and postoperative factors were found to be associated with such VTE events. The identification of risk factors for VTE in both patient populations raises the question of VTE prophylaxis in select high-risk subpopulations.


This is an Open Access Thesis.

Open Access

This Article is Open Access