Prophylactic Low-Molecular-Weight Heparin Versus Unfractionated Heparin in Spine Surgery (PLUSS): A Pilot Matched Cohort Study

Abstract

BACKGROUND Despite a proven superior efficacy of prophylactic low-molecular-weight heparin (LMWH) over unfractionated heparin (UFH) in the majority of surgical specialties, chemoprophylactic techniques after spine surgery have not been established because of the fear of epidural hematomas with LMWH. OBJECTIVE To determine the efficacy of LMWH vs UFH in the prevention of venous thromboembolism (VTE) events, balanced against the risk of epidural hematoma. METHODS This is the first matched cohort design that directly compares prophylactic LMWH to UFH after spine surgery for degenerative/deformity pathologies at a tertiary academic center. Prospectively collected patients receiving prophylactic LMWH and a historical cohort of patients receiving prophylactic UFH (prior to 2017) were matched in 1:1 ratio based on age ±5 yr, American Society of Anesthesiologists classification, location in the spinal column, and type of surgery. RESULTS Of 562 patients, VTE events equaled 1.4% (n = 8): 1.4% (n = 4) with LMWH was exactly equal to 1.4% (n = 4) with UFH. Epidural hematomas reached 0.8% (n = 5): 1.4% (n = 4) with UFH vs 0.3% (n = 1) with the LMWH (P = .178). Utilizing adjusted odds ratio (ORadj), the type of chemoprophylaxis after spine surgery failed to predict VTE events. Similarly, the chemoprophylactic technique failed to predict epidural hematoma in the multivariable regression analysis, although UFH trended toward a higher complication rate (ORadj = 3.15 [0.48-20.35], P = .227). CONCLUSION Chemoprophylactic patterns failed to predict VTE. Although no differences in epidural hematoma rates were detected, our analysis does highlight a trend toward a safer profile with LMWH vs UFH. LMWH may be a safe alternative to UFH in spine surgery.

Chemical prophylaxis and venous thromboembolism following elective spinal surgery: A systematic review and meta-analysis

“…Countries of origin included the United States (52.6%), China (15.8%), United Kingdom (10.5%), Iran (10.5%), Canada (5.3%), and Australia (5.3%). Fourteen studies used patient data from single-center institutional populations, with an average sample size of 1,145 [14 , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , 35] . Two studies used data from national databases, comprising an average sample size of 101,864 [36 , 37] .…”

Rivaroxaban versus nadroparin for thromboprophylaxis following thoracic surgery for lung cancer: A randomized, noninferiority trial

“…Pharmacological prophylaxis with UFH or LMWH is recommended to be initiated preoperatively (2–12 h prior to surgery) and given postoperatively within 6–12 h, as per the current guidelines 46 . In recent years, it has been clinically shown that LMWH may be as effective as low‐dose subcutaneous UFH for thromboprophylaxis in patients undergoing orthopedic or general surgery; however, the risk of bleeding complications is lower with LMWH 47–49 . Furthermore, long‐term therapy using LMWH has been reported to be linked to fewer heparin‐related complications, such as osteoporosis, allergic skin reactions, and heparin‐induced thrombocytopenia, than UFH 50 .…”

“…46 In recent years, it has been clinically shown that LMWH may be as effective as low-dose subcutaneous UFH for thromboprophylaxis in patients undergoing orthopedic or general surgery; however, the risk of bleeding complications is lower with LMWH. [47][48][49] Furthermore, long-term therapy using LMWH has been reported to be linked to fewer heparin-related complications, such as osteoporosis, allergic skin reactions, and heparin-induced thrombocytopenia, than UFH. 50 The higher bioavailability, longer half-life and resulting predictable anticoagulant effect of LMWH also allow for its use in the outpatient setting.…”

Venous thromboembolism risk after spinal cord injury: A secondary analysis of the CLOTT study

“…In a retrospective study of nearly 7,000 consecutive patients from a single center undergoing spine surgery, the rate of epidural hematoma in the chemoprophylaxis group was 0.2% with no significant difference in the group that did not receive chemoprophylaxis (0.18%) 20 . Despite the safety of initiating pharmacologic prophylaxis and the low rates of epidural hematoma, 21,22 there is lack of consensus among spine surgeons as to best practices for initiation of VTEppx in patients undergoing spinal surgery. In one study that surveyed orthopedic and neurosurgical spine surgeons, opinions on the risk of VTEppx on the development of clinically relevant epidural hematoma formation were highly variable, with a majority overestimating the risk of epidural compared with published rates 23 .…”