Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition). Reg Anesth Pain Med. 2010;35:64-101. [PMID: 20052816 DOI: 10.1097/aap.0b013e3181c15c70]

Comparison of analgaesia with lumbar epidurals and lumbar plexus nerve blocks in patients receiving multimodal analgaesics following primary total hip arthroplasty: a retrospective analysis

PURPOSE

Significant post-operative pain occurs after hip arthroplasty. In a prior study, lumbar plexus nerve blocks provided comparable analgaesia to lumbar epidurals; however, multimodal analgaesics were not used consistently.

METHODS

This study assessed a randomly selected cohort of 48 patients undergoing primary hip arthroplasty who received a regional anaesthesia technique for post-operative pain. Twenty-four patients with lumbar epidurals and 24 with single-injection lumbar plexus nerve blocks were reviewed using electronic medical records. Post-operative opiate consumption was the primary endpoint. Secondary endpoints were participation in physical therapy, side effects, and time to discharge. Descriptive statistics were calculated to describe patients in the different groups. Opiate consumption was compared using linear mixed models. Multivariable models were examined for both primary and secondary endpoints.

RESULTS

In comparison with patients receiving lumbar epidural catheters, patients with lumbar plexus blocks consumed less opiates post-operatively at 24-36 and 36-48 hours (P = 0.037 and 0.002, respectively); it did not differ at zero to 12 hours or 12-24 hours post-operatively. Patients with lumbar plexus blocks had earlier times to first ambulation (28.5 ± 3.29 vs 21.9 ± 1.76 h; P = 0.043). However, differences by block type were not observed for ambulation distance, level of assistance to ambulate or time of discharge orders.

CONCLUSIONS

Following primary total hip arthroplasty, lumbar plexus nerve blocks provide effective post-operative analgaesia with decreased opiate consumption compared with lumbar epidural catheters. Lumbar plexus blocks also promote earlier post-operative ambulation and are compatible with post-operative prophylactic anticoagulants.

Novel Anticoagulant Agents in the Perioperative Setting

An increasing number of oral anticoagulants have become available over the past decade. Each of these agents has differing implications on both regional and neuraxial anesthetic techniques. This article describes the pharmacology, pharmacokinetics, and pharmacodynamics of the most commonly used novel oral anticoagulants (NOACs). It also outlines recent guidelines for the use of NOACs in the perioperative setting, especially with regard to neuraxial anesthesia.

Preoperative Assessment of Risk Factors

Hemostasis is essential during endoscopic sinus and skull base surgery. Patients must be adequately assessed for bleeding risk to appropriately consent to surgery. The patient and the surgeon must be aware of the individual bleeding risk for a given procedure. A thorough history and physical examination is the best screening methodology available to determine whether a patient requires further hematologic work-up. Included in this assessment should be any medications and herbals that the patient consumes. This ensures a safe evaluation of the patient, streamlines appropriate consultation and testing when necessary, and confers accurate surgical risk assessment.

Perioperative Considerations and Management of Patients Receiving Anticoagulants

Anticoagulants remain the primary strategy for the prevention and treatment of thrombosis. Unfractionated heparin, low molecular weight heparin (LMWH), fondaparinux, and warfarin have been studied and employed extensively with direct thrombin inhibitors typically reserved for patients with complications or those requiring interventions. Novel oral anticoagulants have emerged from clinical development and are expected to replace older agents with their ease to use and more favorable pharmacodynamic profiles. Increasingly, anesthesiologists are being requested to anesthetize patients who are on some form of anticoagulants and hence it is important to have sound understanding of pharmacology, dosing, monitoring, and toxicity of anticoagulants. We searched the online databases including PubMed Central, Cochrane, and Google Scholar using anticoagulants, perioperative management, anesthetic considerations, and LMWH as keywords for the articles published between 1994 and 2015 while writing this review. In this article, we will review the different classes of anticoagulants and how to manage them in the perioperative settings.

Epidural Versus Paravertebral Nerve Block for Postoperative Analgesia in Patients Undergoing Open Liver Resection: A Randomized Clinical Trial

BACKGROUND AND OBJECTIVES

Although many studies have found no difference between thoracic epidural block and unilateral thoracic paravertebral block after thoracotomy, no previous studies have compared epidural block with bilateral thoracic paravertebral block (bTPVB) in patients undergoing open liver resection. We aimed to investigate whether there was a significant analgesic advantage of thoracic epidural over bTPVB after liver resection.

METHODS

This randomized, prospective, open-label study included adult patients undergoing elective open liver resection. Patients were randomized to receive either thoracic epidural block or bTPVB, through which ropivacaine (0.2%) was infused for 3 days. The primary outcome was pain Verbal Rating Scale (VRS) score (0-10) at rest and with postoperative incentive spirometry. Secondary outcomes included VRS at rest, inspired volumes during incentive spirometry, patient-controlled analgesia hydromorphone utilization, measures of hemodynamic stability, and postoperative bowel function.

RESULTS

Eighty patients completed the study and received thoracic epidural block (n = 41) or bTPVBs (n = 39). No catheter-related complications were noted. The primary outcome, pain (VRS) with incentive spirometry, was significantly lower in the epidural group (epidural vs bTPVB, mean [SD]) (4.5 [2.7] vs 5.4 [2.7] at 24 hours postoperatively, and 3.2 [2.1] vs 4.6 [2.4] at 48 hours postoperatively). Maximal inspired volumes at 24 hours postoperatively (917 [379] vs 1042 [468] mL) and cumulative utilization of patient-controlled analgesia hydromorphone during the first 48 hours postoperatively (10.7 [7.9] vs 13.6 [8.5] mg) were not significantly different between groups. Decrease in mean arterial pressure from baseline at 24 hours postoperatively was greater for the epidural group (-12.6 [15.8] vs -3.8 [16.2]; P = 0.016).

CONCLUSIONS

This study suggests that there is a modest analgesic advantage of thoracic epidural over bTPVBs for patients after open liver resection.

Analysis of contributing factors influencing thromboembolic events after total knee arthroplasty

BACKGROUND

Venous thromboembolic events (VTE) are a known and well-described complication following total knee arthroplasty (TKA). We sought to validate the American College of Chest Physicians thromboprophylaxis recommendations after elective TKA, paying special attention to our dose adjustments for weight, and their impact on VTE in our population.

METHODS

We retrospectively investigated risk factors in patients undergoing TKA, focusing mainly on symptomatic VTE occurrence rates from deep vein thrombosis (DVT) or pulmonary embolism (PE). The anticoagulation protocol consisted of starting low molecular-weight heparin (LMWH) therapy, with dalteparin administered 12 h after surgery in patients who received general anesthesia or 24 h later in patients who received single-dose regional anesthesia.

RESULTS

Data from 346 patients (mean age 66.8 [range 24-91] yr) who underwent primary or revision TKA depicted an overall symptomatic VTE rate of 15%. The proximal DVT rate was 1.7%, and the nonfatal PE rate was 0.9%. The mean time to VTE diagnosis was 5.6 days. The first dalteparin dose was administered 19.5 (range 10-48) h after surgery in patients without VTE and 22.6 (range 11.5-52) h after surgery in patients with VTE (p = 0.003). With a first dose of dalteparin administered 12 h postoperatively, patients presented significantly lower DVT and PE rates than if it was administered 24 h postoperatively (8.5% v. 16.3%, p = 0.048).

CONCLUSION

Delayed administration of LMWH has deleteriously impacted the VTE rate after TKA at our institution. Prompt initiation of LMWH (≤ 12 h after surgery) is appropriate, without increasing the risk of major bleeding.

Comparison of Lumbar Epidurals and Lumbar Plexus Nerve Blocks for Analgesia Following Primary Total Hip Arthroplasty: A Retrospective Analysis

BACKGROUND

Total hip arthroplasty (THA) is associated with significant postoperative pain. Both lumbar epidurals and lumbar plexus nerve blocks have been described for postoperative pain control, but it is unclear if one technique is more beneficial.

METHODS

Using electronic medical records, a randomly selected, cohort of 58 patients with lumbar epidurals were compared with 58 patients with lumbar plexus nerve blocks following primary THA. The primary end point was 48-hour postoperative opiate consumption. Secondary end points included time of first ambulation, distance ambulated, level of assistance with ambulation, presence of side effects, and time to discharge. Descriptive statistics were calculated to characterize subjects in the different block-type groups. Comparisons in morphine consumption were conducted using linear mixed models. Primary and secondary end points were examined in multivariable models.

RESULTS

Patients with lumbar plexus blocks consumed less opiates at 24, 36, and 48 hours relative to patients that received lumbar epidural catheters (P = .047, .002, and .002, respectively). Patients with lumbar plexus blocks ambulated earlier (24.6 ± 2.01 hours vs 31.7 ± 3.01 hours) and farther relative to patients with epidurals (P < .001 for both) and had discharge orders written earlier (58.2 ± 6.68 hours vs 73.6 ± 6.35 hours).

CONCLUSION

In comparison to lumbar epidural catheters, lumbar plexus nerve blocks are an effective pathway for postoperative pain control following primary THA. Furthermore, this clinical pathway expedites physical rehabilitation and is more compatible with postoperative prophylactic anticoagulants.

The Effectiveness and Risks of Fluoroscopically Guided Lumbar Interlaminar Epidural Steroid Injections: A Systematic Review with Comprehensive Analysis of the Published Data

Objective

To determine the effectiveness and risks of fluoroscopically guided lumbar interlaminar epidural steroid injections.

Design

Systematic review of the literature with comprehensive analysis of the published data.

Interventions

Three reviewers with formal training in evidence-based medicine searched the literature on fluoroscopically guided lumbar interlaminar epidural steroid injections. A larger team consisting of five reviewers independently assessed the methodology of studies found and appraised the quality of the evidence presented.

Outcome Measures

The primary outcome assessed was pain relief. Other outcomes such as functional improvement, reduction in surgery rate, decreased use of opioids/medications, and complications were noted, if reported. The evidence on each outcome was appraised in accordance with the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) system of evaluating evidence.

Results

The search yielded 71 primary publications addressing fluoroscopically guided lumbar interlaminar epidural steroid injections. There were no explanatory studies and all pragmatic studies identified were of low quality, yielding evidence comparable to observational studies.

Conclusions

The body of evidence regarding effectiveness of fluoroscopically guided interlaminar epidural steroid injection is of low quality according to GRADE. Studies suggest a lack of effectiveness of fluoroscopically guided lumbar interlaminar epidural steroid injections in treating primarily axial pain regardless of etiology. Most studies on radicular pain due to lumbar disc herniation and stenosis do, however, report statistically significant short-term improvement in pain.

Thoracic epidural catheter for postoperative pain control following an ineffective transversus abdominis plane block using liposome bupivacaine

A 24-year-old female with a history of ulcerative colitis underwent colectomy. The patient received an ineffective transversus abdominis plane (TAP) block with liposome bupivacaine (Exparel) intraoperatively and was started on a hydromorphone patient-controlled analgesia 5 hours after the TAP block, which did not relieve her pain. A continuous thoracic epidural (CTE) was then placed after blood levels of bupivacaine were drawn, and the patient immediately experienced significant pain relief. The combined use of liposome bupivacaine and bupivacaine CTE infusion in the postoperative management of this patient demonstrated no safety concerns, provided excellent analgesia and plasma concentrations of bupivacaine remained far below toxic levels.

Ultrasound-guided peripheral nerve blocks in anticoagulated patients - case series

BACKGROUND AND OBJECTIVES

The advent of ultrasound has brought many benefits to peripheral nerve blocks. It includes both safety and effectiveness, given the possibility of visualizing the neurovascular structures and the needle during the procedure. Despite these benefits, there is no consensus in the literature on the use of this technique in anticoagulated patients or with other coagulation disorders. Moreover, peripheral blocks vary in depth, spreadability, and possibility of local compression. However, few societies take it into account when drawing up its recommendations, establishing a single recommendation for performing peripheral blocks, regardless of the route used. The objective of this series is to expand the discussion on peripheral nerve block in anticoagulated patients.

CASE REPORTS

This series reports 9 cases of superficial peripheral nerve blocks guided by ultrasound in patients with primary or secondary dyscrasias. All blocks were performed by experienced anesthesiologists in the management of ultrasound, and there was no bruising or neurological injuries in the cases.

CONCLUSIONS

This case series support the discussion on conducting surface peripheral nerve blocks and easy local knowledge as the axillary, interscalene, femoral, saphenous or popliteal in anticoagulated patients, on dual antiaggregation therapy and/or with other coagulation disorders, provided that guided by ultrasound and performed by an anesthesiologist with extensive experience in guided nerve blocks. However, larger series should be performed to prove the safety of the technique for these patients.

Coagulative safety of epidural catheters after major upper gastrointestinal surgery: advanced and routine coagulation analysis in 38 patients

BACKGROUND

The risk of spinal haematoma in patients receiving epidural catheters is estimated using routine coagulation tests, but guidelines are inconsistent in their recommendations on what to do when results indicate slight hypocoagulation. Postoperative patients are prone to thrombosis, and thromboelastometry has previously shown hypercoagulation in this setting. We aimed to better understand perioperative haemostasis by comparing results from routine and advanced tests, hypothesizing that patients undergoing major upper gastrointestinal surgery would be deficient in vitamin K-dependent coagulation factors because of malnutrition, or hypocoagulative because of accumulation of low molecular weight heparin (LMWH).

METHODS

Thirty-eight patients receiving epidural analgesia for major upper gastrointestinal surgery were included. We took blood at the time of preoperative epidural catheterization and at catheter withdrawal. Prothrombin time-international normalized ratio (PT-INR), activated partial thromboplastin time (aPTT) and platelet count (Plc) were analysed, and also albumin, proteins induced by vitamin K absence (PIVKA-II), rotational thromboelastometry (ROTEM®), multiple electrode aggregometry (Multiplate®) and activities of factors II, VII, IX, X, XI, XII and XIII.

RESULTS

Postoperative coagulation was characterized by thrombocytosis and hyperfibrinogenaemia. Mean PT-INR increased significantly from 1.0 ± 0.1 to 1.2 ± 0.2 and mean aPTT increased significantly from 27 ± 3 to 30 ± 4 s. Activity of vitamin K-dependent factors did not decrease significantly: FIX and FX activity increased. FXII and FXIII decreased significantly. Mean Plc increased from 213 ± 153 × 10⁶/L while all mean ROTEM-MCFs (maximal clot firmnesses) especially FIBTEM-MCF increased significantly to above the reference interval. All mean ROTEM® clotting times were within their reference intervals both before and after surgery. ROTEM® (HEPTEM minus INTEM) results were spread around 0. There were significant correlations between routine tests and the expected coagulation factors, but not any of the viscoelastic parameters or PIVKA-II. Multiplate® area under curve and EXTEM-MCF correlated significantly to Plc as did EXTEM-MCF to fibrinogen, FIX, FX and FXIII; and FIBTEM-MCF to Plc, FII, FXI and FXIII.

CONCLUSIONS

The increase in PT-INR may be caused by decreased postoperative FVII while the elevated aPTT may be caused by low FXII. The mild postoperative hypocoagulation indicated by routine tests is not consistent with thromboelastometry. The relevance of ROTEM® and Multiplate® in the context of moderately increased routine tests remains unclear. Trial registration number is not applicable since this is not a clinical trial.

Administration of Coagulation-Altering Therapy in the Patient Presenting for Oral Health and Maxillofacial Surgery

Oral health care providers are concerned with how to manage patients prescribed coagulation-altering therapy during the perioperative/periprocedural period for dental and oral surgery interventions. Management and recommendation can be based on medication pharmacology and the clinical relevance of coagulation factor levels/deficiencies. Caution should be used with concurrent use of medications that affect other components of the clotting mechanisms; prompt diagnosis and any necessary intervention to optimize outcome is warranted. However, evidence-based data on management of anticoagulation therapy during oral and maxillofacial surgery/interventions is lacking. Therefore, clinical understanding and judgment are needed along with appropriate guidelines matching patient- and intervention-specific recommendations.

Guidance for the practical management of the direct oral anticoagulants (DOACs) in VTE treatment

Venous thromboembolism (VTE) is a serious medical condition associated with significant morbidity and mortality, and an incidence that is expected to double in the next forty years. The advent of direct oral anticoagulants (DOACs) has catalyzed significant changes in the therapeutic landscape of VTE treatment. As such, it is imperative that clinicians become familiar with and appropriately implement new treatment paradigms. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance for VTE treatment with the DOACs. When possible, guidance statements are supported by existing published evidence and guidelines. In instances where evidence or guidelines are lacking, guidance statements represent the consensus opinion of all authors of this manuscript and are endorsed by the Board of Directors of the Anticoagulation Forum.

The authors of this manuscript first developed a list of pivotal practical questions related to real-world clinical scenarios involving the use of DOACs for VTE treatment. We then performed a PubMed search for topics and key words including, but not limited to, apixaban, antidote, bridging, cancer, care transitions, dabigatran, direct oral anticoagulant, deep vein thrombosis, edoxaban, interactions, measurement, perioperative, pregnancy, pulmonary embolism, reversal, rivaroxaban, switching, \thrombophilia, venous thromboembolism, and warfarin to answer these questions. Non- English publications and publications > 10 years old were excluded. In an effort to provide practical information about the use of DOACs for VTE treatment, answers to each question are provided in the form of guidance statements, with the intent of high utility and applicability for frontline clinicians across a multitude of care settings.

Perioperative management of patient with intracoronary stent presenting for noncardiac surgery

As the number of percutaneous coronary interventions increase annually, patients with intracoronary stents (ICS) who present for noncardiac surgery (NCS) are also on the rise. ICS is associated with stent thrombosis (STH) and requires mandatory antiplatelet therapy to prevent major adverse cardiac events. The risks of bleeding and ischemia remain significant and the management of these patients, especially in the initial year of ICS is challenging. The American College of Cardiologists guidelines on the management of patients with ICS recommend dual antiplatelet therapy (DAT) for minimal 14 days after balloon angioplasty, 30 days for bare metal stents, and 365 days for drug-eluting stents. Postponement of elective surgery is advocated during this period, but guidelines concerning emergency NCS are ambiguous. The risk of STH and surgical bleeding needs to be assessed carefully and many factors which are implicated in STH, apart from the type of stent and the duration of DAT, need to be considered when decision to discontinue DAT is made. DAT management should be a multidisciplinary exercise and bridging therapy with shorter acting intravenous antiplatelet drugs should be contemplated whenever possible. Well conducted clinical trials are needed to establish guidelines as regards to the appropriate tests for platelet function monitoring in patients undergoing NCS while on DAT.

Fontan's circulation with dextrocardia, recent pulmonary embolism, and inferior vena cava filter: Anesthetic challenges for urgent hysterectomy

Fontan's circulation is a unique challenge for the anesthesiologist. Venous pressure is the only source of blood flow for the pulmonary circulation. Patients with such circulation are extremely sensitive to progression of cyanosis (decreased pulmonary blood flow) or circulatory failure. Any major venous compression can compromise the pulmonary blood flow worsening cyanosis; simultaneously, an increased afterload can precipitate circulatory failure. We present a rare patient of surgically corrected Ivemark syndrome with Fontan's physiology with dextrocardia who developed a large uterine fibroid compressing inferior vena cava (IVC). As a result of compression, not only the pulmonary circulation was compromised but she also developed stasis-induced venous thrombosis in the lower limbs that lead to pulmonary embolism (PE) (increased afterload). In addition to oral anticoagulation an IVC filter was inserted to prevent ongoing recurrent PE. Further, to prevent both circulatory compromise and deep venous thrombosis an urgent myomectomy/hysterectomy was planned. In the present case, we discuss the issues involved in the anesthetic management of such patients and highlight the lacunae in the present guidelines for managing perioperative anticoagulation these situations.