- Clinical Professor of Neurological Surgery, The Albert Einstein College of Medicine, Department of Neurosurgery, Bronx, New York, Chief of Neurosurgical Spine and Education, Winthrop University Hospital, Mineola, New York, President, Long Island Neurosurgical Associates, PC, 410 Lakeville Rd Suite 204, New Hyde Park, New York, USA
Nancy E. Epstein
Clinical Professor of Neurological Surgery, The Albert Einstein College of Medicine, Department of Neurosurgery, Bronx, New York, Chief of Neurosurgical Spine and Education, Winthrop University Hospital, Mineola, New York, President, Long Island Neurosurgical Associates, PC, 410 Lakeville Rd Suite 204, New Hyde Park, New York, USA
DOI:10.4103/2152-7806.103866Copyright: © 2012 Epstein NE. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Epstein NE. How much medicine do spine surgeons need to know to better select and care for patients?. Surg Neurol Int 26-Nov-2012;3:
How to cite this URL: Epstein NE. How much medicine do spine surgeons need to know to better select and care for patients?. Surg Neurol Int 26-Nov-2012;3:. Available from: http://sni.wpengine.com/surgicalint_articles/how-much-medicine-do-spine-surgeons-need-to-know-to-better-select-and-care-for-patients/
Background:Although we routinely utilize medical consultants for preoperative clearance and postoperative patient follow-up, we as spine surgeons need to know more medicine to better select and care for our patients.
Methods:This study provides additional medical knowledge to facilitate surgeons’ “cross-talk” with medical colleagues who are concerned about how multiple comorbid risk factors affect their preoperative clearance, and impact patients’ postoperative outcomes.
Results:Within 6 months of an acute myocardial infarction (MI), patients undergoing urological surgery encountered a 40% mortality rate: similar rates may likely apply to patients undergoing spinal surgery. Within 6 weeks to 2 months of placing uncoated cardiac, carotid, or other stents, endothelialization is typically complete; as anti-platelet therapy may often be discontinued, spinal surgery can then be more safely performed. Coated stents, however, usually require 6 months to 1 year for endothelialization to occur; thus spinal surgery is often delayed as anti-platelet therapy must typically be continued to avoid thrombotic complications (e.g., stroke/MI). Diabetes and morbid obesity both increase the risk of postoperative infection, and poor wound healing, while the latter increases the risk of phlebitis/pulmonary embolism. Both hypercoagluation and hypocoagulation syndromes may require special preoperative testing/medications and/or transfusions of specific hematological factors. Pulmonary disease, neurological disorders, and major psychiatric pathology may also require further evaluations/therapy, and may even preclude successful surgical intervention.
Conclusions:Although we as spinal surgeons utilize medical consultants for preoperative clearance and postoperative care, we need to know more medicine to better select and care for our patients.
Keywords: Hematology, medical comorbidities, neurological/psychiatric -disorders, obesity, pulmonary, spinal surgery: cardiac disease, stroke
Although we obtain preoperative clearance from our medical colleagues, spine surgeons need to know more medicine to better select (e.g., work up, reject) patients for spinal surgery, and to manage them postoperatively. Improved recognition of significant comorbid risk factors should decrease perioperative morbidity, and improve postoperative outcomes. This study attempts to provide a broad, although cursory, overview of multiple medical topics for spinal surgeons that include: cardiac disease, stroke, uncoated/coated stents (cardiac/carotid/peripheral vascular), diabetes, obesity, infection, gastrointestinal disease, hematological diseases, pulmonary disease, neurological disorders, and psychiatric conditions [Tables
Multiple studies document varying levels of operative success, particularly for the more extensive surgical procedures requiring instrumented fusions. In order to better evaluate how multiple comorbidities interact with these operative procedures, the outcomes (successes and failures) of such procedures from selected large studies were analyzed.
Morbidity and mortality of spinal surgery for degenerative lumbar stenosis
Lumbar spinal fusions for degenerative lumbar stenosis are some of the most frequently performed operations. In Fu et al. study, the Scoliosis Research Society (SRS) database for lumbar surgery attributed to degenerative lumbar stenosis was prospectively assessed, and focus was placed on the attendant morbidity and mortality associated with these procedures [
Summary: The surgical complication rate for degenerative lumbar stenosis was 7%, and included new neurological deficits in 0.6% of patients, and a 0.12% mortality rate.
Morbidity and mortality attributed to lumbar surgery for spondylolisthesis
In a retrospective analysis of 10,242 adults with degenerative spondylolisthesis (DS) and isthmic spondylolisthesis (IS), Sansur et al. studied the morbidity/complication rates and mortality (M and M) rates obtained from the SRS database [
Summary: Higher-grade DS, and age over 65 years both significantly correlated with higher complication rates of spinal surgery for DS.
Prospectively collected morbidity and mortality data for patients undergoing spinal surgery yields more accurate results
In 2008, Street et al. prospectively analyzed (over a one-year period) all adverse events (AE) occurring in 942 adults undergoing complex spinal surgery in a major trauma center; these included morbidity (major/minor, medical and surgical) and mortality.[
Summary: The incidence of perioperative morbidity increased from 23% to 87% when data were prospectively collected in a complex spinal surgery trauma center.
Morbidity and mortality in different spinal series
In a 2-year prospective (2003-2004) analysis involving 767 patients undergoing lumbar spine surgery, Lee et al. found the following medical complications: cardiac (13%), pulmonary (7%), gastrointestinal (6.7%), neurological (8.2%), hematological (17.5%), and urological (10.3%) [
Schoenfeld et al. prospectively examined risk factors contributing to immediate postoperative (within 30 days) morbidity/mortality in a large series of patients from the National Surgical Quality Improvement Program (2005-2008) undergoing spine surgery.[
Summary: Varying morbidity and mortality rates have been reported for patients undergoing spinal surgery. These are correlated with the following factors/pathology: cardiac, pulmonary, gastrointestinal, neurological, hematological, urological, prior wound infection, corticosteroid use, history of sepsis, ASA classification of >2, and prolonged operative times.
Major complications/risk factors associated with revision spinal deformity surgery
Cho et al. retrospectively analyzed risk factors contributing to the major complications seen over an average of 3.5 years (follow-up/range of 2-5 years) for 166 patients (averaging 53.8 years of age) undergoing multilevel revisions following previous spinal deformity surgery [
Summary: Patients undergoing secondary procedures for scoliosis had a 34.4% major complication rate, and poorer outcomes
Morbidity and mortality in spine surgery (including deformity) in older patients
Acosta et al. analyzed the morbidity/complications and mortality for 29 patients undergoing major 5 or more level (average 10 levels, with a range of 5-15) spinal deformity surgery accompanied by fusions.[
Summary: Following major (>5-level) spinal deformity surgery, the overall long-term complication rate was 52%, but only a history of hypertension positively correlated with a 10-fold increase in susceptibility to complications.
Complex spine surgery: Sometimes unnecessary, too much or too little
Epstein found increased complication/morbidity and mortality rates reviewing the literature concerning the frequency of spinal surgical procedures performed in patients aged 65 and over (geriatric) with multiple overlapping comorbidities.[
Epstein further highlighted the incidence of “unnecessary” spine surgery being offered to patients, including geriatric patients, with significant comorbidities with pain alone, but without focal neurological deficits or significant radiographic findings.[
Summary: Increasingly, geriatric and other patients with significant attendant comorbidity factors, are being offered extensive and often “unnecessary” spinal procedures. In Epstein's series, the frequency was 17.2%.
High rate of reoperation for patients undergoing multilevel instrumented fusions with 96% “off-label” use of INFUSE (Medtronic, Memphis, TN, USA)
Epstein also reported on the frequency of complications (morbidity and mortality) arising from multilevel complex spinal fusions utilizing INFUSE (Medtronic, Memphis, TN, USA).[
Summary: The 170 (96%) of 177 patients undergoing instrumented fusions utilizing INFUSE were performed “off-label”, and resulted in a 40% reoperation rate for geriatric patients (aged over 65).
Learning curve for minimally invasive spinal surgery
Ultimately, the value of MIS spine surgery vs. open spinal procedures relies on the comparison of long-term outcomes. While some studies document that MIS procedures′ learning curves “do no harm”, reduce operative time, blood loss, and short-term recovery (time to ambulation), others cite comparable long-term outcomes for MIS vs. open surgery.[
Other MIS series cite major complications attributed to minimally invasive approaches. In Lindley et al. axial lumbar interbody fusion series involving L4-5 and L5-S1 fusions (followed average 34 months), 16 (23.5%) of 68 patients experienced 18 complications (26.5%).[
Summary: Comparable long-term outcomes for MIS vs. open spinal surgical procedures are being reported, but some unique MIS techniques are associated with higher complication rates.
Cardiac disease and risk of acute myocardial infarction with early surgery (defined as within less than 6 months of a myocardial infarction)
A history of a myocardial infarction (MI) within a prior 6 month interval is a relative contraindication to spinal surgery due to the increased risk of a possible fatal cardiac event. Thiagarajah et al. studied the perioperative mortality for 25 patients averaging 88 years of age (range 78-98) undergoing hip surgery (acute proximal femoral neck fractures) within 1-12 days following an acute MI; the mortality rate was 28% within the 1st postoperative month, but increased to 40% by the 6st postoperative month.[
Summary: The risk of perioperative mortality following an acute MI in a series of patients undergoing acute hip surgery was 28% at 1, but 40% at 6 postoperative months. These data may similarly be applied to other operative procedures.
Anti-platelet aggregant therapy for coated vs. uncoated cardiac stents
Increasingly, cardiac revascularization, rather than utilizing bypass procedures, now employs uncoated (bare) or coated stents. If uncoated stents are utilized, spinal surgery and/or other operations must be delayed by at least 6 weeks to 2 months to allow for sufficient endothelialization of the stented vessel to take place; at this point, in some cases, anti-platelet therapy may be safely discontinued. However, for patients receiving a coated stent, spinal surgery must typically be delayed for 6 months to 1 year, as the coating inhibits endothelialization, making anti-platelet therapy imperative to avoid thrombotic complications.
Summary: Spinal surgery may often be performed within 2 months of placing an uncoated stent, but typically requires up to 6 months to 1 year following placement of a coated stent.
Coated stents for acute or recent myocardial infarction
For patients with acute or recent MIs (e.g., within <6 months), performing spinal operations may prove life threatening. In De Servi et al., first and second-generation drug-eluting (coated) stents were performed similarly.[
Summary: Following acute/recent MI (<6 months), the cessation of anti-platelet aggregants to perform spinal operations may lead to complications (mortality, major cardiac events) utilizing first and second-generation coated stents.
Greater safety and efficacy demonstrated for coated vs. uncoated stents
Several studies demonstrate the greater safety and efficacy of coated vs. uncoated stents. Morice et al. compared the efficacy of a sirolimus (rapamycin)-coated stent (that inhibits lymphocyte and smooth-muscle proliferation) vs. uncoated stents for treating patients with chest pain.[
Summary: Six months following the placement of sirolimus coated vs. uncoated stents, the coated stents demonstrated greater retention of luminal diameter, no restenosis (vs. 26.6% uncoated), no thrombosis, and a lesser 5.8% incidence of cardiac events (vs. 28.8% for uncoated stents).
Time-frames for cessation of anti-platelet therapy in urological surgery
In urological surgery, following the placement of uncoated vs. coated cardiac stents, the timing for utilizing anti-platelet therapies varies according to the complexity of the surgery being performed.[
Summary: Time frames for performing various urological procedures following the placement of an uncoated stent were typically 1 month for uncoated vs. 12 months for coated stents. However, schedules for cessation/reinitiation of aspirin and/or clopidogrel bisulfate varied according to the severity of the procedure.
Lumbar surgery and stroke
When Wu et al. evaluated the incidence of stroke (hemorrhagic/ischemic) following lumbar spinal fusion in 2015 patients vs. 120 control subjects, they found that the overall frequency of stroke (9.99 per 1000 person-year) was comparable for both groups.[
Stroke risk for taking patients off anti-platelet or anticoagulant therapy prior to spine surgery: Timing of cessation of medication
For patients with significant cardiac disease (e.g., atrial fibrillation [AFIB]) or carotid disease (stenosis) requiring anti-platelet aggregant therapy or anticoagulants, the risk of peri- and postoperative stroke must be considered before “clearing” patients for spinal surgery. This requires an on-going interaction with medical consultants, as the decision when to safely stop these medications prior to surgery, and when to restart them following surgery, may prove critical to patient outcomes.
When Stieb et al. assessed continuing anticoagulants and antiplatelet aggregant therapies prior to major spine surgery, they found a 50-81% risk for major bleeding requiring transfusion, with a 0.2% to 0.4% incidence of postoperative spinal hematomas warranting surgery (this depended on whether low-molecular-weight heparin (LMWH) was utilized postoperatively.[
Cardioembolic stroke risk
For patients about to undergo major spinal procedures, factors contributing to the risk of cardioembolic stroke once anticoagulation or anti-platelet therapy are stopped include AFIB, recent MI, mechanical prosthetic valve (Mitral Valve Replacement [MVR]), dilated myocardiopathy, and mitral valve rheumatic stenosis.[
Summary: AFIB, recent MI, mechanical prosthetic valve (MVR), dilated myocardiopathy, and mitral rheumatic stenosis are factors that increase the risk of cardioembolic stroke. Cessation of anticoagulants or anti-platelet aggregants prior to spine surgery increase the risk of stroke carrying a 27.3% risk of in-hospital mortality.
Carotid revascularization techniques vs. Carotid artery stenting
Carotid artery disease leading to stroke is the third-leading cause of adult mortality.[
In Papanagiotou et al., successful revascularization of extracranial ICA with acute stent implantation was achieved in 95% of patients (21 patients); there were no acute stent thromboses, intracranial recanalization was achieved with thrombolysis in 61% (11 of 18 patients), and the recanalization rate (extracranial and intracranial) was 63% (14 of 22 patients).[
Summary: Patients with significant carotid disease who are about to undergo major spine surgery may require acute stent implantation which has been correlated with a 95% incidence of success. The timing of surgery will be dictated by the stent utilized with a typical minimum of 6 weeks of anti-platelet therapy for noncoated vs. usually up to 1 year for coated stents.
Assessing the impact of obesity on morbidity and/or mortality associated with spinal surgery is critical. Recognition of obesity as a major risk factor for spinal surgery allows spinal surgeons to (1) avoid operating on “high risk” individuals, or at least to (2) optimize (e.g., recommend weight loss/improve nutrition) patient selection for surgery. When spinal operations are absolutely necessary, (i.e., evolving neurological deficits) procedures should be as uncomplicated as possible, and should be accompanied by limited instrumentation.
Morbid obesity increases the morbidity of spinal surgery
Utilizing The “Healthcare Cost and Utilization Project's California State Inpatient Databases (CA-SID) (California 2003-2007)” that included 84,607 admissions, Kalanithi et al. documented that morbid obesity increases the risks/complications of spinal fusions, especially for those undergoing anterior cervical or posterior lumbar surgery.[
Summary: Although only 1,455 (1.72%) of 84,607 patients undergoing spinal fusions were morbidly obese, they accounted for 97% of in-hospital complications including; longer LOS (4.8 vs. 3.5 days), higher average hospital costs ($108,604 vs. $84,861), and higher (0.41 vs. 0.13) mortality rates.
Obesity risk with spinal surgery and indications for weight reduction including bariatric surgery
Obesity in general and morbid obesity in particular, pose increased risks to any spinal surgical procedure. Morbidly obese patients exhibit an increased risk of phlebitis (deep venous thrombosis (DVT)) and pulmonary embolism (PE). This is not only attributed to greater mechanical venous compression and immobility leading to venous stasis, but also to higher circulating levels of antiphospholipid activating Factor 1. Morbid obesity also offers other significant operative risks that include: difficulty positioning patients at surgery, trouble obtaining adequate localizing films (e.g., X-ray, fluoroscopy), an increased risk of wrong-level surgery, a greater likelihood of poorly executed operative procedures (e.g., technical limitations, including contraindication to lower anterior cervical arthroplasty), increased perioperative wound complications (seromas/hematomas), infection (largely related to a vascular fat pad), and increased estimated blood loss (EBL).
Increased estimated blood loss for morbidly obese patients undergoing spinal surgery
Han et al. documented that the higher body mass index (BMI) associated with morbid obesity leads to increased intra-abdominal pressure (IAP) and intraoperative blood loss (IBL) during spinal procedures performed in the prone position.[
For patients considering various weight reduction strategies (e.g. dieting under a physicians supervision, bariatric surgery) and achieving their goals, complications such as osteopenia/osteoporosis and poor nutritional status may also occur impacting surgical outcome. Alternatively, for those who fail to lose weight, surgery may not be viable.
Summary: Morbid obesity poses an increased risk of DVT/PE (increased levels of antiphospholipid activating Factor 1), wrong-level surgery, poorly executed procedures, wound seromas/hematomas, infection, and greater EBL.
Bariatric surgery increases osteopenia/osteoporosis
There has been an increase in candidates for spinal surgery who have previously undergone gastric bypasses, leaving them vitamin and nutritionally deficient, but more critically, osteopenic or osteoporotic. Fleischer et al. evaluated bone metabolism and bone mineral density (BMD) after Roux-en-Y gastric bypass surgery.[
Summary: Morbidly obese patients undergoing bariatric surgery experience malabsorption of calcium and vitamin D resulting in decreased hip and bone densities.
HEMATOLOGY/ONCOLOGY: COAGULATION SYNDROMES, MANAGEMENT OF PHLEBITIS/PULMONARY EMBOLISM, AND DIAGNOSIS OF CARCINOMATOSIS
Hypocoagulation; genetic syndromes vs. Medication, food, vitamin, or supplement induced
Operative hematological complications may include hypocoagulation syndromes, (e.g., Von Willebrand's Disease (VWD), Hemophilia), or other factors contributing to poor platelet function; medications, vitamins, supplements, or foods; (e.g., myriad of medications including Aspirin, Asacol (for Crohn's disease contains equivalent of 1.5 aspirin/pill), Glucosamaine/Chondroitin Sulfate, Vitamin E, multivitamins, (contains Vitamin E), nuts (Vitamin E), Fish/Fish Oils, Ginkgo biloba, and Omega-3 complexes among others. When marine-based n-3 fatty acids (Omega-3 Fish Oils) were evaluated in a rat model, plasma coagulation parameters resulted in strong hypocoagulation after only 1 week.[
When spine surgery is anticipated, it is optimal to discontinue specific vitamins, foods, or supplements up to 2-3 weeks prior to surgery. A minimum of 10 days is warranted to allow platelets to regenerate.
Summary: Hypocoagulation may be attributed to VWD, and Hemophilia, but it may also be due to multiple medications (aspirin-containing), vitamins (especially Vitamin E, Multivitamins), supplements (fish oils Glucosamaine/Chondroitin Sulfate, Ginkgo biloba), or specific foods (fish, nuts, etc.).
Hypocoagulation with von willebrand's disease: A range of genetic disorders
VWD consists of a range of genetic disorders. “The molecular pathology of Type 2 and 3 VWD is now comprehensively documented and involves rare sequence variants at the Von Willebrand Factor (VWF) locus.”[
Summary: VWD consists of a range of genetic disorders contributing to excessive bleeding, and may be treated pre-, intra-, and post-spinal surgery with desmopressin (DDVAP) and/or the infusion of VWF concentrates.
Hypocoagulation due to hemophilia: “on-demand” vs. “prophylaxis” with factor viii 0 may help reduce annual bleeding rates
Surgical prophylaxis for factor VIII (FVIII) deficiency is often considered the optimal treatment for managing patients about to undergo spinal surgery, as hemophilia poses an increased risk of intraoperative/postoperative hemorrhagic complications. However, even the chronic management of hemophilia without anticipated surgery, with either on-demand or continued prophylaxis, warrants further study.[
Summary: Hemophilic patients with Factor VIII deficiency exhibited fewer ABR if treated prophylactically (keeping FVIII trough levels at or above 1%) vs. those receiving “on demand therapy” (none were ABR free).
Other medications, vitamins, and foods promoting hypocoagulation should be stopped weeks prior to spine surgery
Multiple medications, vitamins, supplements, and foods contribute to hypocoagulation and should, therefore, be stopped prior to spine surgery. This specifically includes the most frequently utilized anti-platelet aggregants (e.g. aspirin, Clopidogrel Bisulfate, Dipyridamole, among others). Additionally, Vitamin E, contained in most multivitamins and present in high doses in nuts, is not only an antioxidant, but also directly inhibits platelet function as protein kinase C decreases platelet pseudopodia formation when stimulated by agonists,thereby reducing platelet adhesion.[
Summary: Various medications (aspirin, Clopidogrel Bisulfate, Dipyridamole), Vitamin E containing compounds (multivitamins, nuts), Glucosamine C hondroitin Sulfate, Ginkgo biloba, fish/fish oils/Omega-3 supplements increase bleeding risk, and should be stopped several weeks (preferably 3) prior to spine surgery.
There are many hypercoagluation syndromes that contribute to increased clumping of thrombocytes and fibrin, leading to arterial/venous thrombosis.[
Summary: There are a multitude of both intrinsic and acquired hypercoagulation syndromes that contribute to arterial/venous thrombosis.
Various management strategies for preventing/managing phlebitis and pulmonary embolism in spine surgery
Over 2 million people in the United States develop DVT, and almost 100,000 have fatal PE.[
Summary: Intermittent CS adequately reduce the risk of DVT/PE in neurosurgical patients, avoiding the hemorrhagic complications of LDH/LMWH regimens: 2-4% (cranial), 3.4% minor and 3.4% major hemorrhages (cranial/spinal), and 0.7% major/minor hemorrhages (spinal series).
Efficacy of alternating compression stockings for deep venous thrombosis/pulmonary embolism prophylaxis for spine surgery
For complex lumbar spine surgery, including laminectomies with instrumented fusions, although LDH regimens reduce the frequency of DVT and PE, they still pose a risk of postoperative hematoma/neurological dysfunction, and/or wound dehiscence.[
Summary: Pneumatic compression stocking prophylaxis resulted in a 2.8% incidence of DVT and 0.7% frequency of PE in 139 patients undergoing complex lumbar fusions; these results were comparable to those reported in other spine series utilizing LDH/LMWH.
Efficacy of low molecular weight heparin for prophylaxis against venous thromboembolism after lumbar surgery
Zhi-Jian et al. evaluated the efficacy and safety of LMWH prophylaxis for venous thromboembolism (VTE) following 78 lumbar decompressions.[
Summary: LMWH prophylaxis, beginning with a half dose administered 6 h postoperatively followed by full dose once a day, reduced DVT/PE to 0, while only 2 patients exhibited minor bleeding complications.
Indications and results of prophylactic inferior vena cava filter placement in high risks patients undergoing spine surgery
As the frequency of PE may reach 13% in high-risk patients undergoing spine surgery, McClendon et al. retrospectively analyzed the value of prophylactically placing preoperative inferior Vena Cava filters (IVCF).[
Summary: Prophylactic IVCF were safely placed in high-risk patients undergoing spine surgery (history of DVT/PE, hypercoagulation, long (>5 levels), 360°, and/or staged operations over 8 h), resulting in an 8.7% incidence of DVT, and 3.7% frequency of PE.
Low threshold for ordering spinal computed tomography contrast angiography for diagnosing postoperative pulmonary embolism
Epstein et al. studied the incidence of positive CTA-PE protocols despite negative Doppler studies of the lower extremities performed in postoperative spinal patients.[
Summary: Spine surgeons should have a “low threshold” for ordering CTA-PE protocols, as the incidence of positive CTA despite negative Doppler studies was 6.7% following cervical laminectomies/fusions, and 3.6% after lumbar laminectomies/noninstrumented fusions.
Transient cessation of warfarin in chronically anticoagulated patients: assessment of peri-procedural (operative) risks of thrombosis and bleeding
Tafur et al. looked at the 3-month risk for thrombosis (if anticoagulation was stopped) or bleeding (depending upon when anticoagulation was restarted) for patients whose chronic anticoagulation was transiently stopped for invasive procedures: (e.g. for DVT (38%), AFIB (30%), and mechanical heart valves (MVR) (27%)).[
Summary: For patients on chronic anticoagulation for AFIB, DVT, or MVR, transient cessation of anticoagulants, and the utilization of LMWH bridging therapy (69%) resulted in a 3-month 2.1% incidence of major bleeding, and an overall 5.1% bleeding rate.
When is it safe to anticoagulate high risk patients after spinal surgery?
When is it safe to anticoagulate patients who are at high risk for thromboembolic events following spinal surgery?[
Summary: Patients undergoing spinal surgery managed without prophylaxis developed PE in 5.3% of deformity, 6% of trauma, and 2.3% of degenerative disease cases. Fatal PE, major bleeding (0.0-4.3%), and hematomas (0.4%) were reportedly rare.
Cancer and hypercoagluation syndromes
Hypercoagulation syndromes, frequently observed in patients with cancer or paraneoplastic syndromes, are the second most prominent cause of death secondary to hemorrhages or thromboses.[
Summary: Hypercoagulation syndromes (thrombophilia, DIC, thrombocytosis), and lower antithrombin III, C-protein and S-protein plasma levels in patients with cancer or paraneoplastic syndromes, are the second most prominent cause of death secondary to hemorrhages or thromboses.
Oncology: Differentiation of leptomeningeal carcinomatosis from lumbar disease
Leptomeningeal disease, particularly carcinomatosis (carcinomas, lymphomas, among others), may mimic lumbar disc disease. In Reggars et al., a 62-year-old male with a several day history of left-sided low back/leg pain with weakness was under treatment (e.g., chemotherapy) for low grade non-Hodgkin's lymphoma.[
Summary: Leptomeningeal disease, particularly carcinomatosis (carcinomas, lymphomas, other), may mimic lumbar disc disease, and should be a diagnostic consideration.
Patients with pulmonary disease/compromise attributed variously to asthma, chronic obstructive pulmonary disease (COPD), pulmonary conditions (e.g., sleep apnea), and lung cancer, may be optimized for spinal surgery, or may not be viable surgical candidates.
Value of asthma assessment and optimization prior to spine surgery
Select asthmatic patients (those with more severe disease) who undergo preventive preoperative pulmonary evaluations and treatment may avoid untoward intraoperative and postoperative events (e.g., bronchospasm). Liccardi et al. recommended assessing patients at least 1 week prior to surgical procedures involving general anesthesia.[
Summary: At least 1 week prior to spine surgery, patients with significant asthma should undergo preoperative pulmonary assessment (spirometry) to determine whether “optimization” with bronchodilators, inhaled steroids, Cromalyn Sodium, Montelukast, or other measures are warranted.
Chronic obstructive pulmonary disease
Patients with COPD need to be carefully screened to determine whether they are candidates for spinal surgery (inclusive of medications). Santus et al. characterized COPD as “neutrophilic airway inflammation and oxidative stress modulated via Leukotriene B (4) (LTB (4)), a potent proinflammatory mediator”, and recommended that clinically employing bronchodilators may optimize these patients for spine surgery.[
Summary: Utilization of bronchodilators for patients with COPD may facilitate optimizing them for spinal surgery.
Cessation of smoking prior to spinal surgery: Duration of 4-8 weeks correlates with respiratory benefits
The negative musculoskeletal impacts of smoking on patients undergoing spinal surgery are well known.[
Summary: Cessation of smoking >4-8 weeks prior to surgery reduced respiratory complications, while the failure to quit smoking within <2-4 weeks of surgery did not. Additionally, cessation of smoking 3-4 weeks preoperatively improved wound healing.
Increased risks of sleep apnea and respiratory complications in diabetic patients undergoing spinal surgery
In Plantigna et al. series, sleep apnea positively correlated with the diagnosis of diabetes.[
Summary: Sleep apnea is more prevalent in diabetic patients who, if undiagnosed prior to lumbar surgery, are susceptible to hypoventilation, aspiration, and pneumonia while utilizing routine narcotic pain medication.
There may be a role for spinal, epidural, combined spinal/epidural, and local anesthesia in spinal surgery
Some have found that spinal/local anesthetic techniques offer several advantages over general anesthesia for lumbar spinal surgery.[
Jellish et al. further documented better postlaminectomy and microdiskectomy outcomes utilizing spinal bupivacaine with epidural clonidine, and local infiltration of. 0.5% bupivacaine at the lumbar incision sites in 120 patients.[
Duger et al. also documented the efficacy (postoperative analgesia/sedation) and reduced side effects associated with utilizing epidural, or combined spinal/epidural anesthesia vs. spinal anesthesia alone (all with systemic morphine) for performing 64 lumbar lamnectomies.[
Summary: Some authors have documented a reduced perioperative morbidity associated with lumbar surgery performed under spinal (bupivacaine) and/or epidural (clonidine) anesthesia supplemented with local anesthetics (0.5% bupivacaine).
Risk of spinal infections and prophylaxis
The risk of postoperative spinal infections varies from 0.4% to 3.5%, but may be reduced utilizing multiple preoperative, intraoperative, and postoperative measures.[
Summary: The risk of postoperative spinal infections varies from 0.4% to 3.5%, but may be reduced utilizing multiple preoperative, intraoperative, and postoperative preventative measures.
Avoiding nosocomial surgical site infections
Harrop et al. observed that the majority of surgical site infections (SSI) were nosocomial (e.g., hospital-acquired contaminant/infections), and that these led to revision surgery, delayed wound healing, increased use of antibiotics, and increased LOS.[
Sound levels including talking in the operating room and at the operating room table contribute to surgical site infections
Kurmann et al. documented what many of us already know; that talking in the operating room and/or at the operating room table may increase the risk of SSI.[
Summary: Measures required to avoid SSI, especially nosocomial, include; proper skin preparation, vigilant sterile technique, shorter operative procedures, fewer personnel walking in and out of the operating room, and limiting noise levels/talking.
Comparative efficacy of two skin preparation solutions (chloraprep and duraprep) utilized for spine surgery
The relative efficacy of different skin preparation solutions utilized prior to spine surgery has been thoroughly investigated. Savage et al., in a prospective randomized study, evaluated two commonly used skin preparation solutions for 100 consecutive patients undergoing lumbar spinal surgery.[
Summary: Two commonly utilized skin preparation solutions (ChloraPrep and DuraPrep) provided comparable skin prophylaxis for spinal surgery.
Hibiclens (chlorhexidine) bathing may reduce central venous catheter infections
Montecalvo et al. observed that prophylaxis with Hibiclens (CHG 2%) vs. soap and water significantly reduced the incidence of infection/sepsis following the placement of central venous catheters; 2.6/1000 central venous catheter days (Chlorhexidine) vs. 6.4/1000 central venous catheter days (soap and water).[
Efficacy of daily bathing with chlorhexidine for reducing healthcare-associated blood stream infections
O’Horo et al. studied the beneficial impact of daily bathing with Chlorhexidine (CHG) for avoiding blood stream infections (BSI) in various hospital (including intensive care unit (ICU)) settings.[
Bathing prior to and following spinal surgery with hibiclens (chlorhexidine gluconate)
In many institutions, a routine measure utilized to avoid spinal SSI is to bathe with Hibiclens the night before and the morning of spinal surgery. Hibiclens operative sponges may be dispensed at same day testing. Epstein also recommended that patients bathe with Hibiclens for up to 2 weeks prior to surgery, and receive Hibiclens baths twice a day while hospitalized postoperatively.[
Summary: Daily bathing with Chlorhexidine (CHG) avoids BSI. Many hospitals provide CHG brushes for bathing the night before and the morning of surgery to reduce SSI. Others promote even longer preoperative utilization of CHG baths (e.g., for up to 2 weeks preoperatively, during the hospital stay, and postopertively).
Antibiotic prophylaxis for spinal surgery utilizing a cephalosporin
There is an ongoing debate as to which antibiotic prophylaxis regimens are better/best for avoiding SSI. Petignat et al. in a double-blind, placebo-controlled, randomized clinical trial, established the efficacy of a single dose of 1.5 g cefuroxime in preventing lumbar disc SSI (up to 6 months postoperatively).[
Efficacy of cefuroxime and gentamicin as prophylaxis against Methicillin-resistant Staphylococcus aureus
Hammond et al. evaluated the prevalence of MRSA in 175 patients transferred to neurosurgery units; screening occurred in 61% of patients, 15% of whom were MRSA positive.[
Epstein recommended that the optimal antibiotic prophylactic regimen to prevent SSI should include utilizing 2 gm of a cephalosporin (e.g., Cefazolin) administered within 1 h of surgery (others prefer 15 minutes), and one preoperative dose of Gentamicin (dose tailored to the patient) as additional prophylaxis against MRSA.[
Summary: Cefuroxime and Gentamicin provide increased prophylaxis against MRSA at the time of induction of anesthesia for patients undergoing spine surgery.
Silver impregnated dressings may limit postoperative wound infections
Biffi et al. evaluated in a randomized, double-blind trial, the value of silver impregnated antimicrobial dressings (Aquacel (R) Ag Hydrofiber) in preventing SSI (over 30 postoperative days) for patients undergoing elective surgery for colorectal cancer.[
Barnea et al. also reviewed the utility of Aquacel Ag (R) that contained soft nonwoven sodium carboxymethylcellulose fibers integrated with ionic silver; they found it to be both safe and effective in reducing various types of wound infections.[
The incidence of SSI was lowered by utilizing silver impregnated dressings in 106 of Epstein's patients undergoing lumbar spinal surgery.[
Summary: Silver impregnated dressings did not significantly limit/reduce the incidence of wound infections in a series of patients undergoing elective colon surgery, however, it did appear to reduce postoperative deep and superficial wound infections following lumbar-instrumented fusions.
Rare esophageal perforation following anterior cervical surgery and thoracic fractures
Esophageal injuries/perforations are infrequently encountered following anterior cervical surgery or spinal trauma. Patients with continued drainage, fever, infection, and dysphagia 1 week following an anterior cervical procedure, must be suspected of having sustained an esophageal tear.[
Summary: Esophageal injuries/perforations are infrequently encountered following anterior cervical surgery or spinal trauma. Continued drainage, fever, infection, and dysphagia 1 week following anterior cervical surgery should prompt one to suspect an esophageal tear. The surgical approach, and the potential for a major esophageal complication with anterior cervical procedures, should prompt careful consideration of the alternative, posterior cervical surgery, when feasible.
Diagnosis of multiple sclerosis
Multiple Sclerosis (MS), a chronic demyelinating disease involving the central nervous system, often presents with variable manifestations; atypical motor deficits, sensory findings, and spasticity (hyper-reflexic symptoms/signs).[
Summary: Establishing the diagnosis of MS is often delayed. In one series, it took an average of 2.2 years before patients were referred to a neurologist, and an average of 3.5 years (following the initial onset of symptoms) before MS was correctly diagnosed.
Differentiating multiple sclerosis from cervical spondylotic myeloradiculopathy, and recognizing MS-related deficits and types
It is often difficult to differentiate the symptoms and signs of MS from cervical spondylotic myeloradiculopathy (CSM).[
Summary: The symptoms and signs of MS that may “mimic” cervical CSM, typically include; motor (33%), multisystem (33%), and cerebellar disorders (16%). The three major types of MS are primary progressive-MS (62%), secondary progressive-MS (22%), or relapsing-remitting-MS (16%).
Barkhof criteria seen on magnetic resonance scans in multiple sclerosis patients
The Barkhof Criteria as observed on MR scans of MS patients include: “(a) at least 1 gadolinium-enhancing lesion or at least 9 lesions on T2-weighted images, (b) at least 3 periventricular lesions, (c) at least 1 juxtacortical lesion, and (d) at least 1 infratentorial lesion′.[
Summary: The Barkhof Criteria observed on MR scans of MS patients include: “(a) at least 1 gadolinium-enhancing lesion or at least 9 lesions on T2-weighted images, (b) at least 3 periventricular lesions, (c) at least 1 juxtacortical lesion, and (d) at least 1 infratentorial lesion.”
Intramedullary cervical plaque (C4-C7) consistent with adolescent multiple sclerosis
Selviardis et al. reported a 15-year-old female who presented with progressive spastic quariparesis, attributed to an MR-documented, hyperintense (on T2 weighted images) intramedullary spinal lesion extending from C3-C7.[
Summary: Intramedullary spinal MS lesions may mimic intrinsic spinal cord tumors. In order to avoid inadvertent biopsy of these lesions, additional preoperative studies (e.g., evoked response testing, other tests) to rule out MS are warranted.
Differentiation of cervical spondylotic myeloradiculopathy from neuromyelitis optica (Neuromyelitis optica or devic syndrome)
It is important to differentiate spinal pathology from Devic Syndrome (Neuromyelitis optica (NMO)).[
Summary: NMO (Devic Syndrome) is a disabling inflammatory process that targets astrocytes in the optic nerves and spinal cord, but unlike MS, only 50% of patients experience isolated unilateral optic neuritis. Preventive measures include broad-spectrum or selective B-lymphocyte immune suppression, and acute attacks can be managed with high-dose intravenous steroids, and occasional plasma exchange.
Differentiating amyotrophic lateral sclerosis from spinal disease
Amyotrophic lateral sclerosis (ALS) is a progressive neurological disorder. Differentiating ALS from other treatable/untreatable disorders (e.g., multifocal motor neuropathy, CSM, or MS) early in the clinical course may avert unnecessary spinal surgery, and other therapeutic interventions.[
Summary: The diagnosis of ALS is often delayed for up to 11 months, and 31.1% of patients initially receive incorrect diagnoses.
Psychiatric disorders and spine disease
It is critical to recognize when concurrent, significant psychiatric disease is present in patients with spinal complaints, especially when considering them for spinal surgery. Patients with psychiatric disorders and pain alone, without focal neurological deficits, and/or positive radiographic findings, should be treated conservatively (without surgery) by neurologists and psychiatrists. However, for patients with significant psychiatric pathology, with pain and critical neurological and/or radiographic findings, the decision to treat conservatively (without surgery) vs. surgically becomes far more complex. Studies focusing on psychiatric comorbidities in patients with spinal complaints (pain alone vs. pain with significant neurological deficits/radiographic pathology) differ in terms of their recommendations for or against surgical intervention.[
Summary: Studies focusing on psychiatric comorbidities in patients with spinal complaints (pain alone vs. pain with significant neurological deficits/radiographic pathology) differ in terms of their recommendations for or against surgical intervention.
Microdiskectomy (Surgery) was effective and improved depression
Even with significant underlying depression, in carefully selected cases where spinal pathology is clear and focal, as with microdiskectomy, surgery may be effective. Lebow et al. evaluated 100 patients who underwent microdiskectomy, and followed them for depression, somatization, and mental well-being postoperatively for 6 weeks, and 3, 6, and 12 months.[
Summary: Microdiscectomy significantly improve pain-associated depression, somatic anxiety, and mental well-being in patients with herniated lumbar disc.
Depression and anxiety negatively impact outcomes of instrumented fusion for failed back surgery
Despite the best intentions, the documented need for spinal surgery (e.g. positive radiographic and physical examination findings), and correctly performed surgery, some patients with significant psychiatric pathology will still exhibit poor outcomes. In Arts et al., 82 patients with failed back syndromes were evaluated prior to secondary spinal instrumented fusions on multiple outcome scales (including psychiatric scales); VAS, functional disability (Roland Disability Questionnaire for Sciatica (RDQ), ODI, and The Hospital Anxiety and Depression Scale (HADS).[
Summary: In a series of patients with failed back syndromes, secondary spinal fusions resulted in a high failure rate (65%), with nearly one-third of patients exhibiting anxiety/depression disorders. Conservative management may be more beneficial and selective and careful assessment should be performed to prevent unnecessary surgery.
As spine surgeons, expanding our medical knowledge, particularly regarding major comorbidity risk factors, should help us improve patient selection and more effectively treat patients with spine disease. After all, we along with our medical colleagues, share a common goal; promoting the best care and outcomes for our patients.
I would like to thank Ms. Sherry Lynn Grimm, Office Administrator of Long Island Neurosurgical Associates for encouraging me to write and helping to edit this article. I also thank Dr. James Ausman for his astute comments.
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