A systematic review of the literature yielded no studies to adequately address this question.

A systematic review of the literature yielded no studies to adequately address this question.

There is poor quality evidence that routine postoperative assessment for DVT does not reduce the risk of PE in patients undergoing spine surgery; however, screening for high-risk patients may be considered, as it may offer benefit. Grade of Recommendation: C

Yoshioka et al1, studied 4 distinct patient groups: Group 1 comprised patients with lumbar spinal stenosis treated with posterior decompression without fusion; Group 2 included patients with lumbar or lower thoracic degenerative disease treated with instrumentation for spine fusion; Group 3 consisted of patients with cervical degenerative disease treated with posterior decompression or instrumentation for fusion; and Group 4 comprised patients with spinal tumors treated with total spondylectomy or piecemeal excision with stabilization. Deep venous thrombosis (DVT) and pulmonary thromboembolism (PTE) screening were conducted for all 340 patients between 7 to 10 days postoperatively. All 340 patients received mechanical prophylaxis, such as compression stockings and intermittent pneumatic compression devices, from the induction of general anesthesia to postoperative ambulation. No anticoagulation medications were used for prophylaxis against VTE. Duplex ultrasonography assessments of both lower extremities and lung perfusion scintigraphy were performed 7 to 10 days postoperatively to ensure that any asymptomatic thromboembolism was not overlooked. The overall incidence of VTE was 13.5% (46/340), with a DVT rate of 11.8% (40/340) and a PTE rate of 2.9% (10/340). However, no patients experienced symptomatic DVT, and only 0.59% (2/340) experienced symptomatic PTE. Statistically significant factors that increased risk for VTE identified in the univariable analysis included advanced age, neurologic deficits, spinal tumor, intraoperative blood loss, and duration of bed rest. No significant differences were found in operative time or body mass. Multivariate analysis revealed that advanced age, neurological deficits, and spinal tumor resulted risk factors for VTE. This study provides Level IV evidence indicating the necessity for screening for PTE in high-risk patients. Kim et al2, performed a retrospective, observational study of all patients who underwent a spiral CT after spine surgery to evaluate for pulmonary embolism (PE) and deep vein thrombosis (DVT). Of the total 3331 patients undergoing spine surgery, 136 patients had spiral CT scans to evaluate for PE and proximal DVTs, and 130 were included in the final analysis. Investigators evaluated surgical procedure type, PE risk factors, CT scan indicators, prophylactic anticoagulation, and DVT/PE size, location, and treatment. The authors found that the history of PE / DVT was the only significant risk factor for a positive CT scan. Symptoms including tachycardia / arrhythmia, syncope, chest pain, and shortness of breath did not show significant associations. Risk factors including smoking, use of estrogen or oral contraceptives, and history of cancer also did not show any significant association. The surgical approach was not predictive of a positive CT scan. The study provides Level III evidence that CT scans can be positive without evidence of DVT, and patients with a history of PE / DVT may require more aggressive prophylaxis including preoperative temporary IVC filters and should be monitored more closely for signs and symptoms of thromboembolic complications. Epstein et al3 performed an analysis of 240 patients undergoing spine surgery and subsequently had negative lower extremity ultrasounds but a positive spiral computed tomography contrast angiography for PE. Two groups were included: 75 patients who underwent cervical laminectomies and multilevel fusions and 165 patients who underwent lumbar laminectomies and in situ posterolateral lumbar fusion. All patients had routine ultrasounds for DVTs, and those with signs and symptoms for a PE underwent a spiral computed tomography contrast angiography (CTA). Patients with a positive PE but a negative ultrasound were further evaluated on the severity of the PE and evaluation of hypercoagulation syndromes. The authors found that 11 patients (4.6%) experienced a PE despite negative ultrasound results, and those patients were treated with an inferior vena cava filter. Those patients with significant symptoms associated with their PE were also treated with full-dose anticoagulation. This study provides Level IV evidence that routine postoperative assessment for DVT does not reduce the risk of PE in patients undergoing elective spine surgery. Dearborn et al4 performed a prospective analysis of 116 spine surgery patients and a retrospective analysis of 318 patients to determine the incidence of symptomatic and occult DVT and PE after spinal reconstructive surgery. All prospectively studied patients had one duplex ultrasound postoperatively by the same ultrasound technologist between 3-20 days postoperatively to determine the incidence of DVTs. 73 of these patients also had a combined ventilation/perfusion (V/Q) scan to evaluate for a pulmonary embolism. Patients with symptoms of a DVT were scanned emergently. In the retrospective study, only patients with symptoms of a DVT or PE underwent doppler or perfusion scans. Only one patient in the prospective group had a positive DVT scan. The DVT was asymptomatic, and her surgery was complicated by an iliac vein laceration that required repair. However, three patients in the prospective group (2.6%) had PEs, and none of these patients had risk factors. All four of these patients underwent anterior / posterior procedures. In the retrospective group, 1 patient had an asymptomatic DVT, 7 patients had symptomatic PEs, and one patient had a fatal PE. Six of the 7 PEs occurred in patients undergoing combined anterior / posterior spinal fusions. Only 1 of the 7 PEs occurred in a patient undergoing only a posterior lumbar surgery. None of the patients with PEs had a DVT according to their clinical record. This study provides Level III evidence that routine postoperative assessment of DVT does not reduce the risk of PE in patients undergoing elective thoracolumbar surgery. Duplex ultrasound appeared insensitive for diagnosing clots before embolization in this patient group.

References

1. Yoshioka K, Murakami H, Demura S, et al. Comparative study of the prevalence of venous thromboembolism after elective spinal surgery. Orthopedics. 2013;36(2):e223-e228. doi:10.3928/01477447-20130122-26
2. Kim HJ, Walcott-Sapp S, Adler RS, Pavlov H, Boachie-Adjei O, Westrich GH. Thromboembolic Complications Following Spine Surgery Assessed with Spiral CT Scans: DVT/PE Following Spine Surgery. HSS J. 2011;7(1):37-40. doi:10.1007/s11420-010-9179-7
3. Epstein NE, Staszewski H, Garrison M, Hon M. Pulmonary embolism diagnosed on computed tomography contrast angiography despite negative venous Doppler ultrasound after spinal surgery. J Spinal Disord Tech. 2011;24(6):358-362. doi:10.1097/BSD.0b013e3181fee66a
4. Dearborn JT, Hu SS, Tribus CB, Bradford DS. Thromboembolic complications after major thoracolumbar spine surgery. Spine (Phila Pa 1976). 1999;24(14):1471-1476. doi:10.1097/00007632-199907150-00013