Anticoagulation and Spine Surgery

Obstacles in "Time to Spine": Challenges for the Timely Delivery of Acute Surgical Care for Patients with Traumatic and Non-Traumatic Spinal Cord Injury

Over the past three decades, advancements in our understanding of the pathophysiology of spinal cord injury (SCI) have underscored the critical importance of early treatment for both traumatic and non-traumatic cases. Early surgical intervention significantly improves outcomes by limiting the extent of secondary damage. Despite numerous studies highlighting the superior outcomes associated with early decompression surgery for patients with SCIs, hospital reviews reveal that less than 60% of patients undergo surgical decompression within 24 h of injury. This occurs despite consensus among physicians regarding the benefits of early surgery. Therefore, it is important to highlight the multifactorial causes of this knowledge to action discordance. This review aims to elucidate the administrative, logistical, and technical challenges that hinder timely access to surgery for SCIs.

The effect of high-normal preoperative international normalized ratios on postoperative outcomes and complications following posterior cervical spine surgery

INTRODUCTION

Current guidelines recommend that the International Normalized Ratio (INR) be less than 1.5 prior to spine intervention. Recent studies have shown that an INR > 1.25 is associated worse outcomes following anterior cervical surgery. We sought to determine the risk of complications associated with an INR > 1.25 following elective posterior cervical surgery.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was queried. Patients undergoing elective posterior cervical surgery from 2012 to 2016 with an INR level within 24 h of surgery were included. Primary outcomes were hematoma requiring surgery, 30-day mortality, and transfusions within 72-hours. There were 815 patients in the INR ≤ 1 cohort (Cohort A), 410 patients in the 1 < INR ≤ 1.25 cohort (Cohort B), and 33 patients in the 1.25 < INR ≤ 1.5 cohort (Cohort C).

RESULTS

Cohort C had a higher rate of transfusion (4% Cohort A; 6% Cohort B; 12% Cohort C; p = 0.028) and the rate of mortality within 30 days postoperatively trended toward significance (0.4% Cohort A; 0.5% Cohort B; 3% Cohort C; p = 0.094). There was no significant difference in the rate of postoperative hematoma formation requiring surgery (0.2% Cohort A; 0% Cohort B; 0% Cohort C; p = 0.58). On multivariate analysis, increasing INR was not associated with an increased risk of developing a major complication.

CONCLUSION

An INR > 1.25 but ≤ 1.5 may be safe for posterior cervical surgery. An INR > 1.25 but ≤ 1.5 was associated with a significantly higher rate of transfusions. However, increasing INR was not significantly associated with increased risk of any of the major complications.

The Influence of Preoperative Anticoagulant and Antiplatelet Therapy on Rebleeding Rates in Patients Suffering from Spinal Metastatic Cancer: A Retrospective Cohort Study

INTRODUCTION

The age of patients requiring surgery for spinal metastasis, primarily those over 65, has risen due to improved cancer treatments. Surgical intervention targets acute neurological deficits and instability. Anticoagulants are increasingly used, especially in the elderly, but pose challenges in managing bleeding complications. The study examines the correlation between preoperative anticoagulant/antiplatelet use and bleeding risks in spinal metastasis surgery, which is crucial for optimizing patient outcomes.

MATERIAL AND METHODS

In a retrospective study at our department from 2010 to 2023, spinal tumor surgery patients were analyzed. Data included demographics, neurological status, surgical procedure, preoperative anticoagulant/antiplatelet use, intra-/postoperative coagulation management, and the incidence of rebleeding. Coagulation management involved blood loss assessment, coagulation factor administration, and fluid balance monitoring post-surgery. Lab parameters were documented at admission, preop, postop, and discharge.

RESULTS

A cohort of 290 patients underwent surgical treatment for spinal metastases, predominantly males (63.8%, n = 185) with a median age of 65 years. Preoperatively, 24.1% (n = 70) were on oral anticoagulants or antiplatelet therapy. Within 30 days, a rebleeding rate of 4.5% (n = 9) occurred, unrelated to preoperative anticoagulation status (p > 0.05). A correlation was found between preoperative neurologic deficits (p = 0.004) and rebleeding risk and the number of levels treated surgically, with fewer levels associated with a higher incidence of postoperative bleeding (p < 0.01).

CONCLUSIONS

Surgical intervention for spinal metastatic cancer appears to be safe regardless of the patient's preoperative anticoagulation status. However, it remains imperative to customize preoperative planning and preparation for each patient, emphasizing meticulous risk-benefit analysis and optimizing perioperative care.

Risk factors for in-hospital mortality in geriatric patients aged 80 and older with axis fractures: a nationwide, cross-sectional analysis of concomitant injuries, comorbidities, and treatment strategies in 10,077 cases

PURPOSE

To investigate the association between treatment, comorbidities, concomitant injuries, and procedures with in-hospital mortality in patients aged 80 years or older with axis fractures.

METHODS

Data were extracted from the German InEK (Institut für das Entgeltsystem im Krankenhaus) GmbH database (2019-2021) for patients aged 80 years or older with axis fractures and the in-hospital mortality rate was calculated. Differences in comorbidities and concomitant diseases and injuries were analyzed using the Chi-square test. In surgically treated patients, odds ratios (OR) with 95% confidence intervals (95% CI) were used to analyze potential risk factors for in-hospital mortality.

RESULTS

Among 10,077 patients, the in-hospital mortality rate was 8.4%, with no significant difference between surgically (9.4%) and non-surgically treated patients (7.9%; p = 0.103). The most common comorbidities were essential hypertension (67.3%), atrial fibrillation (28.2%), and chronic kidney disease (23.3%), while the most common concomitant injuries were head and face wounds (25.9%), concussions (12.8%), and atlas fractures (11.6%). In surgically treated patients, spinal cord injury (OR = 4.62, 95% CI: 2.23-9.58), acute renal failure (OR = 3.20, 95% CI: 2.26-4.53), and acute bleeding anemia (OR = 2.06, 95% CI: 1.64-2.59) were associated with increased in-hospital mortality (all p < 0.01). Screw-rod-system fixation of one segment (OR = 0.74, 95% CI: 0.56-0.97) and intraoperative navigation (OR = 0.45, 95% CI: 0.16-0.71) were identified as potential protective factors (both p < 0.05).

CONCLUSION

Comprehensive geriatric assessment and optimization of comorbidities during treatment are crucial. The indication for surgical treatment must be carefully individualized. Future studies should focus on the choice of surgical technique, perioperative blood management, and intraoperative navigation as potential protective factors.

The Effect of High-Normal Preoperative International Normalized Ratios on Outcomes and Complications After Anterior Cervical Spine Surgery

Hematoma after anterior cervical spine surgery can result in neurologic and airway compromise. Current guidelines recommend an international normalized ratio (INR) <1.5 before elective spine surgery because of increased complications. The risk associated with an INR of 1.25 is not well studied. The purpose of this study was to determine the risk of complications associated with a preoperative INR >1.25 and ≤1.5 in patients undergoing elective anterior cervical spine surgery. The American College of Surgeons National Surgical Quality Improvement Program database was queried. Patients undergoing elective anterior cervical spine surgery from 2012 to 2016 who had an INR recorded within 24 hours of surgery were included. Outcomes of interest included postoperative hematoma requiring surgery, 30-day mortality, and 30-day readmissions and reoperations. A total of 2949 patients were included. The incidence of a postoperative hematoma that required surgical management was 0.2%, 0.6%, and 4.5% in the INR≤1, 11.25 and ≤1.5 before elective anterior cervical spine surgery is associated with significantly higher rates of postoperative hematoma formation as well as 30-day readmission and reoperation; there was a trend toward significance in mortality rate. [Orthopedics. 2024;47(1):e26-e32.].

Safety of Continuing Aspirin Use in Cervical Laminoplasty: A Propensity Score-Matched Analysis

Introduction

Aspirin is commonly used for the primary and secondary prevention of cardiovascular disease and stroke. Controversy exists concerning whether and when is the optimal time to stop aspirin before spinal surgery. Previous studies on this topic mainly focused on patients who received thoracolumbar spine surgeries. There are only a few literatures concerning the safety of aspirin use in cervical spine surgery patients.

Methods

This pilot study recruited patients who received cervical laminoplasty from January 2010 to December 2021. The operation time, intraoperative blood loss, and postoperative complications of the patients who had taken aspirin during the perioperative period were compared with age, sex, and comorbidity-matched control patients. Propensity score matching was utilized in the selection of control to minimize bias.

Results

Twenty-one patients who have received cervical laminoplasty while taking aspirin during the perioperative period were included. The control group included 21 age, sex, and comorbidity-matched patients who have not taken aspirin. The operation time and intraoperative and postoperative blood loss were higher in patients taking aspirin but were not statistically significant. There was no statistically significant difference in the wound infection rate. No case of epidural hematoma was found.

Conclusions

In patients undergoing cervical laminoplasty, a continuation of aspirin is safe and does not increase the difficulty of the surgery, wound complication, or hemorrhage.

Fondaparinux Sodium: Recent Advances in the Management of Thrombosis

Fondaparinux sodium is a chemically synthesized selective factor Xa inhibitor approved for the prevention and treatment of venous thromboembolic events, that is, deep vein thrombosis, pulmonary embolism, and superficial vein thrombosis, in acutely ill (including those affected by COVID-19 or cancer patients) and those undergoing surgeries. Since its approval in 2002, the efficacy and safety of fondaparinux is well demonstrated by many clinical studies, establishing the value of fondaparinux in clinical practice. Some of the advantages with fondaparinux are its chemical nature of synthesis, minimal risk of contamination, 100% absolute bioavailability subcutaneously, instant onset of action, a long half-life, direct renal excretion, fewer adverse reactions when compared with direct oral anticoagulants, and being an ideal alternative in conditions where oral anticoagulants are not approved for use or in patients intolerant to low molecular weight heparins (LMWH). In the last decade, the real-world use of fondaparinux has been explored in other conditions such as acute coronary syndromes, bariatric surgery, in patients developing vaccine-induced immune thrombotic thrombocytopenia (VITT) and in pregnant women with heparin-induced thrombocytopenia (HIT), or those intolerant to LMWH. The emerging data from these studies have culminated in recent updates in the guidelines that recommend the use of fondaparinux under various conditions. This paper aims to review the recent data and the subsequent updates in the recommendations of various guidelines on the use of fondaparinux sodium.

Who bleeds during elective anterior lumbar surgery?

Background

Blood loss (BL) during elective anterior lumbar access for interbody fusion or disc replacement is a potentially major complication. This study sought to identify factors other than major vascular injury which contribute to BL and therefore this risk. Factors suggested to effect blood loss include age, increasing body mass index (BMI), sex, prothesis, intraoperative heparinization and continuation of low-dose aspirin (LD-ASA).

Methods

A Cell Saver was used in all cases with BL measured and recorded by an independent autotransfusionist. Heparin was administered intravenously when one or both of 2ndtoe saturation metre signal/s lost pulsatility indicating lower limb arterial flow was interrupted.

Results

The mean age of the 364 patients was 47 ± 13.2 yrs. [95% CI: 45 - 48]; and 191 (52%) were male. Age, BMI and heparinization showed a positive correlation with increased BL. There was no significant association with continuation of low-dose ASA with increased BL. Most patients underwent an ALIF - 265 (72%), 52 (14%) had a TDR, and 47 (13%) had a hybrid operation. There was a significant increase in mean BL between single- and two-level procedures in the non-heparinised group (48 vs 83 mls, p = 0.003). Intraoperative heparinization was administered in 102 patients (28%). The total mean BL for the heparin group (104 ml) which was significantly higher than for the non-heparin group (53 ml) (p = 0.001). Heparinisation did not significantly increase the mean BL in single or double level ALIF patients but did significantly increase the BL in single level TDR (57 vs 151 mls, p = 0.039).

Conclusions

Younger, leaner, non-heparinized, single level ALIF patients represented the lowest bleeding risk in anterior lumbar surgery. Conversely, older, increasing BMI, two operative levels, TDR prosthesis and heparinization represent the highest bleeding risk. Continuation of LD-ASA was not associated with an increase in BL.

Comparison between rivaroxaban versus enoxaparin for venous thromboembolism prophylaxis following spine surgeries, a randomized clinical trial

BACKGROUND

Enoxaparin is currently used for VTE prophylaxis. Rivaroxaban is more cost-effective and is as potent as enoxaparin in VTE prophylaxis.

METHODS

The study was held at Al-Zahra and Kashani university hospitals in Isfahan, Iran, from January 2019 to October 2020. Two hundred ninety-six patients requiring instrumented spine surgery were enrolled; 23 were excluded (lack of consent/interfering medical situations). They were randomized into the groups of rivaroxaban (case, n = 137) and enoxaparin receiving (control, n = 136). Medical data were recorded and 244 patients (case = 123, control = 121) were analyzed value < 0.05 was meaningful.

RESULTS

150 patients were males, and 94 were females. The mean age was 52.09 ± 12.6 years. Postoperative drain volume was higher in rivaroxaban received patients than in enoxaparin (p = 0.02). Post-operation epidural hematoma was detected in 3 patients in the case and 1 in the control group, which was not meaningful(p = 0.622). All of them were evacuated surgically. POH was associated with cervical canal stenosis surgery, existing comorbidities, and new medical events. New medical events were associated with postoperative wound dehiscence (p = 0.001). Short and long-term postoperative outcomes were similar in both groups. The mean follow-up duration was 25.8 ± 7.5 months.

CONCLUSION

Rivaroxaban is as effective as enoxaparin in venous thromboembolic event prophylaxis. Regarding postoperative epidural hematoma, statistical analysis showed equal safety of both drugs. Still, the authors would like to recommend more discretion in rivaroxaban administration in cervical spine laminectomy until future studies are conducted.

The incidence of stroke among selected patients undergoing elective posterior lumbar fusion: a retrospective cohort study

BACKGROUND

Although stroke is a rare complication among spinal surgery patients, the recognition of this adverse event is critical given the aging population undergoing surgical procedures. The objective of this study was to estimate the incidence of stroke among selected adults undergoing elective posterior lumbar fusion (PLF) during various post-operative risk windows and among different subgroups.

METHODS

A retrospective cohort study using a longitudinal electronic healthcare record (EHR) database was conducted from January 1, 2007 to June 30, 2018. Elective PLF, stroke, and select clinical characteristics were defined based on International Classification of Disease codes. Patients aged 18 to 85 years with ≥183 days of enrollment in the database prior to undergoing elective PLF were followed from the index date until the occurrence of stroke, death, loss to follow-up, or end of study period, whichever occurred first. The incidence of stroke was estimated in the following risk windows: index hospitalization, ≤ 30 days, ≤ 90 days, ≤ 180 days, and ≤ 365 days post-operation.

RESULTS

A total of 43,063 patients were eligible for the study. The incidence of stroke following elective PLF was 0.29% (95% confidence interval [CI]: 0.25, 0.35%) during index hospitalization, 0.44% (95% CI: 0.38, 0.50%) ≤ 30 days, 0.59% (95% CI: 0.52, 0.67%) ≤ 90 days, 0.76% (95% CI: 0.68, 0.85%) ≤ 180 days, and 1.12% (95% CI: 1.03, 1.23%) ≤ 365 days post-operation. Stratified analyses revealed that older patients had a higher incidence of stroke. Additionally, black patients had higher stroke incidences. Post-operative stroke incidence was higher among patients with a history of type 2 diabetes than among patients without such history; similarly, stroke incidence was higher among patients with a history of stroke compared to patients without such history.

CONCLUSIONS

The incidence of stroke following elective PLF using an EHR database in this study is slightly higher than that reported in the literature. Our results suggest that stroke risk modification prior to PLF may be important for patients who are older, black, type 2 diabetic, and/or have a history of stroke.