Factors associated with venous thromboembolic events following ICU admission in patients undergoing spinal surgery: an analysis of 1269 consecutive patients

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Venous thromboembolic events (VTEs) are a common cause of morbidity and mortality after spine surgery. Patients admitted to the intensive care unit (ICU) following spine surgery exhibit high-risk clinical characteristics.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The authors retrospectively analyzed 1269 ICU patients who had undergone spine surgery between January 1, 2009, and May 31, 2015. Relevant demographic, procedural, and outcome variables were collected.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>Patients admitted to the ICU postoperatively had a postoperative VTE rate of 10.2%, compared to 2.5% among all spine surgery patients during the study period. ICU patients had a higher comorbid disease burden (odds ratio [OR] 1.45, p &lt; 0.001), and were more likely to have a history of a bleeding disorder (2.60% vs 0.46%, OR 2.85, p = 0.028), receive a transfusion (OR 4.81, p &lt; 0.001), have a fracture repaired (OR 4.30, p &lt; 0.001), have an estimated blood loss &gt; 500 ml (OR 1.95, p = 0.009), have an osteotomy (OR 20.47, p = 0.006), or have a corpectomy (OR 3.48, p = 0.007) than patients not admitted to the ICU. There was a significant difference in time to VTE between patients undergoing osteotomy and patients undergoing scoliosis corrections without osteotomy (p = 0.0431), patients with fractures (p = 0.0113), and patients undergoing fusions for indications other than scoliosis or fracture (p = 0.0056). Patients who developed a deep vein thrombosis (DVT) during their ICU stay were more likely to have received a prophylactic inferior vena cava filter placement (OR 8.98, p &lt; 0.001), have undergone an interbody fusion procedure (OR 2.38, p = 0.037), have a history of DVT (OR 3.25, p &lt; 0.001), and have shorter surgery times (OR 0.30, p = 0.002). Patients who developed a pulmonary embolism (PE) during the ICU stay were more likely to have a history of PE (OR 12.68 p = 0.015), history of DVT (OR 5.11, p = 0.042), fracture diagnosis (OR 7.02, p = 0.040), and diagnosis of scoliosis (OR 7.78, p = 0.024). Patients with higher BMIs (OR 0.85, p = 0.036) and those who received anticoagulation treatment (OR 0.16, p = 0.031) were less likely to develop a PE during their ICU stay.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>Patients admitted to the ICU following spine surgery have a higher rate of VTE than non-ICU patients. Time to VTE varied by pathology. Factors independently associated with VTE in the ICU are distinct from factors otherwise associated with VTE. Some factors are independently associated with VTE throughout the 30-day postoperative period, while others are associated with VTE specifically during the initial ICU stay or after leaving the ICU.</jats:p></jats:sec>

The incidence and risk factors of thromboembolism in patients with traumatic spine fractures in a tertiary care hospital

“…This finding controverts with most studies that presented a significant association between neurological injuries of spine and developing VTE in spinal patients. [18,19] On the other hand, some of these factors were found to be associated with VTE in other studies as well, for instance, a longer duration of the hospital [20] and ICU [21] stay. Both circumstances led to decreased physical activity, which will increase the risk of developing thrombosis by affecting Virchow's triad.…”

Recommendations from the ICM-VTE: Spine

“…Infection has been shown to increase VTE risk in multiple studies, with an OR of 18.5 in a 1:2 matched cohort of 85 VTE, and an incidence of 10.7% in a database study of 357,926 patients 51,55 . Similarly, a retrospective study of 6,869 patients with 1,269 postoperative ICU admissions reported a VTE incidence of 10.2% in the ICU group and 2.5% in the non-ICU group despite an increased use of chemoprophylaxis in the former group 54 .…”

“…This relationship has also been elucidated separately for cervical and thoracolumbar procedures, with studies reporting OR of 5.2 or 1.8, respectively 50,51 . Furthermore, any surgery for infection or requiring an ICU admission should be considered high-risk 51,54,55 . Infection has been shown to increase VTE risk in multiple studies, with an OR of 18.5 in a 1:2 matched cohort of 85 VTE, and an incidence of 10.7% in a database study of 357,926 patients 51,55 .…”

Commentary: Surgical Site Infection in the Intensive Care Setting After Posterior Spinal Fusion: A Case Series Highlighting the Microbial Profile, Risk Factors, and the Importance of Comorbid Disease Burden

“…1,2 Some patients are admitted to the intensive care unit (ICU) after PSF, and they are susceptible to atypical pathogens uniquely present in the ICU environment. [3][4][5][6][7] The authors conducted a retrospective study at a single institution over a 15-year period and identified 3965 patients who underwent PSF. 8 They examined the differences in microbial profile of SSIs in PSF patients admitted to the ICU vs non-ICU after surgery.…”

“…1,2 Some patients are admitted to the intensive care unit (ICU) after PSF, and they are susceptible to atypical pathogens uniquely present in the ICU environment. 3-7…”