Effects of epidural anesthesia on the incidence of deep-vein thrombosis after total knee arthroplasty

Bilateral Total Ankle Arthroplasty

Patients with bilateral ankle arthritis have higher rates of primary and secondary/inflammatory arthritis and a more debilitating condition than those with unilateral pathology. The limited bilateral total ankle arthroplasty (TAA) literature supports both 1-surgeon and 2-surgeon team bilateral TAAs as safe and effective with comparable improvements in patient-reported outcome measures (PROMs), complications, reoperations, and prosthesis survival as unilateral TAA and staged bilateral TAA. Additional benefits of bilateral arthroplasty supported in the hip and knee literature include cost reduction, noninferior and even superior perioperative complication profiles, improved PROM and satisfaction, shorter recovery time, early rehabilitation, and less time away from employment.

Spinal Versus General Anesthesia in Total Knee Arthroplasty: Are There Differences in Complication and Readmission Rates?

BACKGROUND

Spinal anesthesia (SP) utilization continues to expand in total knee arthroplasty (TKA). However, little is known regarding differences in complication rates between spinal and general anesthesia used for primary TKA. Therefore, the purpose of this study is to compare the length of stay (LOS), operative time, and readmission and revision rates between patients who received spinal and general anesthesia during TKA.

METHODS

The American Joint Replacement Registry (AJRR) was used to identify primary elective TKA patients from 2017 to 2020. Patients were divided into 2 cohorts, general (GN) and SP, based on the mode of anesthesia administered during the index surgery. In total, 270,251 TKAs were identified, of which 126,970 (47.0%) received general anesthesia and 143,281 (53.0%) received spinal anesthesia. Length of stay, operative time, 90-day readmission, and 90-day revisions were compared between the 2 groups. Multivariable logistic regression analyses were used to adjust for potential confounders.

RESULTS

After accounting for confounding factors, SP was associated with a lower risk of having a LOS greater than 3 days (odds ratio [OR] 0.470, 95% confidence interval [CI] 0.454-0.487, P < .0001), but a slightly higher likelihood of having a longer operative time (OR 1.075, 95% CI 1.056-1.094, P < .0001). SP was also linked to lower rates of 90-day readmission (OR 0.845, 95% CI 0.790-0.904, P < .0001) and lower risk of 90-day all-cause revision (OR 0.506, 95% CI 0.462-0.555, P < .0001).

CONCLUSION

SP was associated with a lower 90-day readmission rate and a lower risk of 90-day revision. These findings support the best practice guidelines of The Joint Commission to use spinal anesthesia when possible as part of an enhanced recovery after surgery (ERAS) pathway.

Association of Neuraxial Anesthesia With Postoperative Venous Thromboembolism After Noncardiac Surgery: A Propensity-Matched Analysis of ACS-NSQIP Database

BACKGROUND

Neuraxial anesthesia improves components of the Virchow's triad (hypercoagulability, venous stasis, and endothelial injury) which are key pathogenic contributors to venous thrombosis in surgical patients. However, whether neuraxial anesthesia reduces the incidence of venous thromboembolism (VTE) remain unclear. We therefore tested the primary hypothesis that neuraxial anesthesia reduces the incidence of 30-day VTE in adults recovering from orthopedic surgery. Secondarily, we tested the hypotheses that neuraxial anesthesia reduces 30-day readmission, 30-day mortality, and the duration of postoperative hospitalization.

METHODS

Inpatient orthopedic surgeries from American College of Surgeons National Surgical Quality Improvement Program database (2011-2015) in adults lasting more than 1 hour with either neuraxial or general anesthesia were included. Groups were matched 1:1 by propensity score matching for appropriate confounders. Logistic regression model was used to assess the effect of neuraxial anesthesia on 30-day VTE, 30-day mortality, and readmission, while Cox proportional hazard regression model was used to assess its effect on length of stay.

RESULTS

Neuraxial anesthesia decreased odds of 30-day VTE (odds ratio 0.85, 95% confidence interval, 0.78-0.95; P = .002) corresponding to number-needed-to-treat of 500. Although there was no difference in 30-day mortality, neuraxial anesthesia reduced 30-day readmission (odds ratio 0.90, 98.3% confidence interval, 0.85-0.95; P < .001) corresponding to number-needed-to-treat of 250 and had a shortened hospitalization (2.87 vs 3.11; P < .001).

CONCLUSIONS

Neuraxial anesthesia appears to provide only weak VTE prophylaxis, but can be offered as an adjuvant to current thromboprophylaxis in high-risk patients.

Anaesthetic care of patients undergoing primary hip and knee arthroplasty: consensus recommendations from the International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) based on a systematic review and meta-analysis

BACKGROUND

Evidence-based international expert consensus regarding anaesthetic practice in hip/knee arthroplasty surgery is needed for improved healthcare outcomes.

METHODS

The International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) systematic review, including randomised controlled and observational studies comparing neuraxial to general anaesthesia regarding major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, genitourinary, thromboembolic, neurological, infectious, and bleeding complications. Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, from 1946 to May 17, 2018 were queried. Meta-analysis and Grading of Recommendations Assessment, Development and Evaluation approach was utilised to assess evidence quality and to develop recommendations.

RESULTS

The analysis of 94 studies revealed that neuraxial anaesthesia was associated with lower odds or no difference in virtually all reported complications, except for urinary retention. Excerpt of complications for neuraxial vs general anaesthesia in hip/knee arthroplasty, respectively: mortality odds ratio (OR): 0.67, 95% confidence interval (CI): 0.57-0.80/OR: 0.83, 95% CI: 0.60-1.15; pulmonary OR: 0.65, 95% CI: 0.52-0.80/OR: 0.69, 95% CI: 0.58-0.81; acute renal failure OR: 0.69, 95% CI: 0.59-0.81/OR: 0.73, 95% CI: 0.65-0.82; deep venous thrombosis OR: 0.52, 95% CI: 0.42-0.65/OR: 0.77, 95% CI: 0.64-0.93; infections OR: 0.73, 95% CI: 0.67-0.79/OR: 0.80, 95% CI: 0.76-0.85; and blood transfusion OR: 0.85, 95% CI: 0.82-0.89/OR: 0.84, 95% CI: 0.82-0.87.

CONCLUSIONS

Recommendation: primary neuraxial anaesthesia is preferred for knee arthroplasty, given several positive postoperative outcome benefits; evidence level: low, weak recommendation.

RECOMMENDATION

neuraxial anaesthesia is recommended for hip arthroplasty given associated outcome benefits; evidence level: moderate-low, strong recommendation. Based on current evidence, the consensus group recommends neuraxial over general anaesthesia for hip/knee arthroplasty.

TRIAL REGISTRY NUMBER

PROSPERO CRD42018099935.

Changes in Markers of Thrombin Generation and Interleukin-6 During Unicondylar Knee and Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is associated with a risk of thromboembolism requiring routine thromboprophylaxis, but there is debate about the risk with unicondylar knee arthroplasty (UKA) as it is a more minor procedure. We sought to investigate the relative risk of thromboembolism with UKA compared to TKA and one-staged bilateral TKA (BTKA) by measuring the increase in circulating biochemical markers of thrombin generation during the procedures. Degree of surgical trauma was also assessed by measuring interleukin-6, a marker of metabolic injury.

METHODS

We prospectively studied a total of 75 patients: 25 patients undergoing UKA, unilateral TKA, and BTKA, respectively. All patients had surgery performed with tourniquet and received no tranexamic acid. Blood samples were taken during surgery and assayed for circulating markers of thrombin generation: prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complexes plus interleukin-6.

RESULTS

Thrombin-antithrombin complexes, increased during all time points (P < .001) but was not significantly different between surgical treatment groups. F1+2 also rose significantly during surgery, with no significant difference between UKA and TKA. There was, however, a significant difference in F1+2 between BTKA and UKA or TKA (P < .02). Interleukin-6 rose minimally with UKA but rose significantly with TKA and BTKA (P < .001).

CONCLUSION

Based on these data of circulating biochemical markers, patients undergoing UKA are at similar risk of thromboembolism with respect to TKA despite a lower index of metabolic injury. We believe that UKA patients should receive thromboprophylaxis comparable to TKA patients.

Comparison of Short-Term Complications of General and Spinal Anesthesia for Primary Unilateral Total Knee Arthroplasty

Purpose

To compare the occurrences of perioperative complications of two anesthetic techniques (general anesthesia [GA] and spinal anesthesia [SA] in patients undergoing primary unilateral total knee arthroplasty (TKA).

Materials and Methods

Patients who underwent unilateral primary TKA due to osteoarthritis from January 2005 to January 2014 were retrospectively reviewed. They were divided into two groups: GA (n=490) and SA (n=746). The operation duration, length of perioperative stay in the operation room and occurrences of adverse events in postoperative 30 days (mean, 29.7±3.1 days) were compared. Before multivariate linear or logistic regression analysis, different baseline characteristics were adjusted in the statistical models.

Results

There were significant intergroup differences in mean age (GA, 68.4±7.2 years; SA, 70.7±7.5 years; p<0.001) and mCCI (GA, 3±1.4; SA, 3.2±1.5; p<0.001). The GA group required longer preoperative room time (+9.4 minutes; p<0.001), postoperative room time (+12.7 minutes; p<0.001), and postoperative hospital stay (+2.5 days; p=0.001) and had more surgical site infections (5 [1%] vs. 0 [0%]; p=0.005) and blood transfusion (205 [41.8%] vs. 262 [35.1%]; p=0.01). No differences in operative duration and other adverse events were identified.

Conclusions

We should cautiously consider that GA may be associated with slightly increased preoperative and postoperative room times, postoperative hospital stay, transfusion and surgical site infection rates in primary unilateral TKA.

Spinal anesthesia increases the risk of venous thromboembolism in total arthroplasty: Secondary analysis of a J-PSVT cohort study on anesthesia

Clinical guidance on the choice of anesthetic modality vis-à-vis the risk of perioperative venous thromboembolism (VTE) is largely lacking because of a paucity of recent evidence. A comparative effect of general anesthesia and neuraxial blockade on the perioperative incidence of VTE has not been well-investigated.We compared the effects of different types of anesthetic modalities on the risk of VTE after total hip arthroplasty (THA) and total knee arthroplasty (TKA).This is a secondary analysis of the Japanese Study of Prevention and Actual Situation of Venous Thromboembolism after Total Arthroplasty (J-PSVT). Data pertaining to a total of 2162 patients who underwent THA and TKA at 34 hospitals were included in this analysis. We compared the different anesthetic modalities with respect to the incidence of VTE. The composite end-point was asymptomatic/symptomatic deep vein thrombosis detected using scheduled bilateral ultrasonography up to postoperative day (POD) 10 and fatal/non-fatal pulmonary embolism up to POD 10.The study groups were as follows: general anesthesia (n = 646), combined epidural/general anesthesia (n = 1004), epidural anesthesia (n = 87), and spinal anesthesia (n = 425). On multivariate analysis, only spinal anesthesia was associated with a significant increase in the risk of VTE as compared with that associated with general anesthesia. Propensity score-matched analysis for "combined epidural/general anesthesia group" versus "spinal anesthesia group" demonstrated a 48% higher incidence of VTE (relative risk = 1.48, 95% confidence interval [CI] 1.18-1.85) in the latter.Spinal anesthesia was associated with a higher risk of postoperative VTE, as compared with that associated with combined epidural/general anesthesia, in patients undergoing total arthroplasty.

Surgical Technique of Total Knee Arthroplasty without Soft Tissue Balance

Total knee arthroplasty (TKA) without soft tissue balance can create a balanced knee to a mechanical axis of near neutral with bone cuts, and remove osteophytes thoroughly. In this study, the authors present detailed steps for performing TKA. The attached video demonstrates the TKA procedure. The patient is a 77-year-old man who had suffered from knee pain for 12 years. Physical examination showed the Apley test to be positive and that the range of motion (ROM) decreased. An X-ray filmed at the positive lateral of the knee joint and the double lower extremity revealed a progression of degenerative osteoarthritis with genu varum. The key point of no soft tissue release is to make a rectangular extensional space by osteotomy. In addition, the osteophytes, especially syndesmophytes, should be removed thoroughly. As a result, the ligaments can achieve ideal length and the flexion contracture can also be remedied. Moreover, in surgeries without soft tissue release, bone mass and normal tissue are retained. Patients are satisfied to the surgery not only with less blood loss, anterior knee pain and DVT, but also faster rehabilitation. In summary, TKA without soft tissue balance is an efficient procedure for patients with knee osteoarthritis which can result in good prognosis.

One-Year All-Cause Mortality of Patients Diagnosed as Having In-Hospital Pulmonary Embolism After Modern Elective Joint Arthroplasty Is Low And Unaffected By Radiologic Severity

BACKGROUND

We studied the 1-year complication rate of patients diagnosed as having a pulmonary embolism (PE) after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) surgery and the distribution of emboli in the pulmonary circulation, and determined if a relationship exists between the location of the PE and age, gender, body mass index, preoperative predisposing factors, American Society of Anesthesiology classification, type of surgery, prophylaxis, hospital stay, transfer to a higher level of care, and mortality.

METHODS

Two hundred sixty-nine patients who developed an in-hospital PE proved by computed tomography pulmonary angiography after elective THA or TKA between 2005 and 2012 were studied.

RESULTS

The most proximal location of the emboli was central in 62, segmental in 139, and subsegmental in 68. Nineteen patients (7%) developed a bleeding complication during PE treatment. Twenty-nine patients (11%) were readmitted during the first year. Two patients (0.74%) died: one had a segmental PE after TKA. He died 11 months after surgery due to an autopsy-proven sepsis. The second patient developed a segmental PE after THA. She was anticoagulated, developed an intracranial bleed, and died 8 months after surgery. Multivariate analysis showed that demographic variables, American Society of Anesthesiology class, preoperative comorbidities (with the exception of arrhythmia), and the presence of preoperative predisposing factors had no effect in the location of the PE.

CONCLUSION

The 1-year mortality rate of these patients is low. Death can be caused by bleeding complications secondary to anticoagulation or by unrelated conditions. This information may aid clinicians while counseling patients who developed a PE after surgery, particularly those with small subsegmental emboli.

Thromboprophylaxis for deep vein thrombosis and pulmonary embolism after total joint arthroplasty in a low incidence population

Postoperative venous thromboembolism is one of the most serious complications following total joint arthroplasty. Pharmacological and mechanical prophylaxis methods are used to reduce the risk of postoperative symptomatic deep vein thrombosis and pulmonary embolism. Use of pharmacological prophylaxis requires a fine balance between the efficacy of the drug in preventing deep vein thrombosis and the adverse effects associated with the use of these drugs. In regions with a low prevalence of deep vein thrombosis such as Korea, there might be a question whether the benefits of using pharmacological prophylaxis outweigh the risks involved. The current article reviews the need for thromboprophylaxis, guidelines, problems with the guidelines, pharmacological prophylaxis use, and the current scenario of deep vein thrombosis, and discusses whether the use of pharmacological prophylaxis should be mandatory in low incidence populations.

II Italian intersociety consensus statement on antithrombotic prophylaxis in orthopaedics and traumatology: arthroscopy, traumatology, leg immobilization, minor orthopaedic procedures and spine surgery

Pharmacological prophylaxis for preventing venous thromboembolism (VTE) is a worldwide established procedure in hip and knee replacement surgery, as well as in the treatment of femoral neck fractures, but few data exist in other fields of orthopaedics and traumatology. Thus, no guidelines or recommendations are available in the literature except for a limited number of weak statements about knee arthroscopy and lower limb fractures. In any case, none of them are a multidisciplinary effort as the one here presented. The Italian Society for Studies on Haemostasis and Thrombosis (SISET), the Italian Society of Orthopaedics and Traumatology (SIOT), the Association of Orthopaedic Traumatology of Italian Hospitals (OTODI), together with the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI) and the Italian Society of General Medicine (SIMG) have set down easy and quick suggestions for VTE prophylaxis in a number of surgical conditions for which only scarce evidence is available. This inter-society consensus statement aims at simplifying the approach to VTE prophylaxis in the single patient with the goal to improve its clinical application.

Guidelines for the management of postoperative pain after total knee arthroplasty

This clinical practice guideline was approved by Korean Knee Society on February 28, 2012. It is based on a systematic review of published studies on the management of postoperative pain after total knee arthroplasty and was developed to include the overall pain management modalities. The purpose of the guideline is to help improve treatment based on current best evidence. Eleven recommendations have been developed based on a systematic review of research evidence and the consensus opinions of a multidisciplinary working group of experts. These recommendations will be revised regularly following systematic review of new research evidence as this becomes available.

Reduction of the incidence of development of venous thromboembolism by ultrasound-guided femoral nerve block in total knee arthroplasty

Background

Venous thromboembolism (VTE) and the subsequent development of pulmonary embolism (PE) is a major cause of post-operative mortality in total knee arthroplasty (TKA). We evaluated whether the addition of an ultrasound-guided femoral nerve block with general anesthesia affected the incidence in the development of VTE following TKA.

Methods

This was a retrospective non-randomized comparative study with patients assigned to groups based on the surgery date (pre-femoral nerve block versus post-femoral nerve block periods). All anesthesia and medical records of the patients who had undergone computer-navigated TKA in our facility between January 2009 and March 2010 were retrospectively reviewed.

Results

Forty patients were identified; 15 patients underwent computer-navigated TKA under general anesthesia alone (Group G) and 25 patients underwent surgery under general anesthesia combined with ultrasound-guided femoral nerve block (Group F). The incidence of development of VTE post-operatively was significantly lower in Group F (P = 0.037). Logistic regression analysis identified the use of a femoral nerve block as the most significant variable correlating with the incidence of post-operative development of VTE, and the odds ratio for VTE development in Group G was 3.12 (95% CI, 0.57-20.56).

Conclusions

We suggest the possibility that the addition of a femoral nerve block on general anesthesia may reduce the incidence of the development of VTE following TKA.

Detection and Prevention of Post-Operative Deep Vein Thrombosis [DVT] Using Nadroparin Among Patients Undergoing Major Abdominal Operations in India; a Randomised Controlled Trial

Deep vein thrombosis [DVT] is one of the most dreaded complications in post-operative patients as it is associated with considerable morbidity and mortality. Majority of patients with postoperative DVT are asymptomatic. The pulmonary embolism, which is seen in 10% of the cases with proximal DVT, may be fatal. Therefore it becomes imperative to prevent DVT rather than to diagnose and treat. Only one randomized trial has been reported from India to assess the effectiveness of low molecular weight heparin in preventing post-operative DVT. To assess the risk of DVT in North Indian patients following major abdominal operations and to evaluate the effectiveness of Nadroparin, A Low Molecular Weight Heparin (LMWH) therapy in preventing post-operative DVT. Sixty five patients were randomised preoperatively into Group-I; Nadroparin prophylaxis and Group-II: No prophylaxis. The primary outcome was the occurrence of DVT, diagnosed by bilateral lower limb venogram performed, seven to ten days after operation. Secondary outcome measures included adverse effects of radio-opaque dye, intra-operative blood loss, operating time, postoperative platelet count, intraoperative blood transfusion requirements and the total duration of postoperative bed rest. No case of DVT occurred in either group. There was no statistical difference in the risk of secondary outcome measures in the two groups. DVT was not observed in any of the patients, even with several high risk factors indicating a possible protective mechanism in the North Indian population.

Periprosthetic joint infection can cause abnormal systemic coagulation

Surgery may often be needed for treatment of patients with a periprosthetic joint infection (PJI). This study intended to evaluate the incidence of abnormal coagulation and determine the efficacy of treatment of reversing a coagulation abnormality in patients with PJI. The cohort included 294 patients undergoing treatment of PJI at our institution from 1998 to 2005. In our final analysis, 72 patients (56%) had abnormal coagulation (defined as international normalized ratio >1.12). Fresh frozen plasma and/or vitamin K were administered to 29 of these patients (40%). The international normalized ratio was normalized in only 7 (24.1%) of the latter patients. It appears that more than one half of patients with PJI may have abnormal coagulation even without being exposed to anticoagulation agents, highlighting the possibility that patients with PJI may have circulating levels of biologically active agents that affect coagulation.

Lessons learned with extended-release epidural morphine after total hip arthroplasty

An extended-release epidural morphine (EREM) has been introduced to improve postoperative pain management. Studies have shown the effectiveness of this agent in providing better pain control and patient satisfaction for patients undergoing total joint arthroplasty. We evaluated postoperative pain relief by comparing average daily pain scores and opioid use with those of the control group. Safety was measured by comparing the occurrence of postoperative complications, nausea and vomiting, pruritus, and respiratory depression between the two groups. Between February 2006 and March 2008, we selected 203 patients to receive EREM for THA. These patients were matched in a 2:1 ratio with patients undergoing THA and receiving spinal anesthesia. We retrospectively reviewed all major and minor postoperative complications from a prospective database. Patients receiving EREM had lower pain scores than patients not receiving EREM on Postoperative Day 1 (POD 1) but not POD 2, or POD 3. Patients receiving EREM experienced a slightly higher incidence of pulmonary embolism and supraventricular tachycardia. Patients receiving EREM also experienced more nausea and vomiting and pruritus. We found EREM provided better pain relief on POD 1 at the expense of a slightly higher incidence of side effects compared with spinal anesthesia alone.

LEVEL OF EVIDENCE

Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

One-Day vs Two-Day Epidural Analgesia for Total Knee Arthroplasty (TKA): A Retrospective Cohort Study

Introduction:

Over 500,000 total knee arthroplasties (TKAs) are performed annually in the US, yet postoperative pain management varies widely. In patients managed with epidural analgesia, the epidural catheter is generally removed on the second postoperative day. We compared in-hospital outcomes associated with removing the epidural catheter on postoperative day 1 (POD1-group) vs on postoperative day 2 (POD2-group) among patients undergoing TKA.

Methods:

We identified 89 patients who had TKA performed by a single surgeon from January through July 2007, and who were managed with epidural analgesia. This study took advantage of a change of policy from removing the epidural on the second postoperative day prior to March 2007 (n = 34) to removing the epidural on the first postoperative day thereafter (n = 55). Data were obtained by medical record review and analyzed with bivariate and multivariate techniques. Outcomes included knee range of motion (ROM), pain (0-10 scale), distance walked, narcotic usage, and length of stay.

Results:

The mean patient age was 68 ± 10 years. We did not identify clinically important differences in preoperative characteristics across groups. Patients in the POD1- group had a shorter length of stay (median of 3 vs 4 days in the POD2-group, p<0.001). The POD1-group also walked a greater distance on the second postoperative day (mean of 38 feet vs 9 feet in the POD2-group, p < 0.002). We did not observe a difference between the two groups with respect to change in passive ROM, pain on the second postoperative day, or narcotic usage. The POD1-group had more restricted continuous passive motion settings on the second postoperative day than the POD2-group (50° vs 65°, p = 0.031), and the POD1-group had somewhat worse passive range of motion at discharge (e.g. passive flexion 82o vs 76o in the POD2- group, p = 0.078).

Conclusion:

The balance between a shorter hospital stay and earlier walking achievement with the POD1-strategy-- vs better ROM at the time of discharge with the POD2-strategy-- should be considered when planning TKA pain management. These results should be confirmed with longer term studies and randomized designs.

Evidence Level III:

Retrospective comparative study.

High incidence of complications from enoxaparin treatment after arthroplasty

Pulmonary embolism (PE) complicates 1% to 10% of total joint arthroplasties and generally requires immediate anticoagulation. Low-molecular-weight heparins have supplanted unfractionated heparin as the treatment of choice for PE and hold a 1A recommendation from the American College of Chest Physicians for this indication. However, the complications of enoxaparin treatment begun in close proximity to arthroplasty surgery are not well described. We examined the records of 135 patients who underwent total joint arthroplasty, experienced an in-hospital PE, and received treatment with enoxaparin at therapeutic doses (1 mg/kg body weight). The type and frequency of complications were determined and classified as major or minor. Twenty-seven percent of patients experienced minor complications and 10% experienced major complications. The incidence of major bleeding was substantially higher than rates reported for nonsurgical patients. The overall complication rate of enoxaparin treatment is similar to the rate of complications reported for unfractionated heparin treatment in this setting, but the complications are less severe.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

A comparison of regional and general anaesthesia for total replacement of the hip or knee: a meta-analysis

We performed a meta-analysis to evaluate the relative efficacy of regional and general anaesthesia in patients undergoing total hip or knee replacement. A comprehensive search for relevant studies was performed in PubMed (1966 to April 2008), EMBASE (1969 to April 2008) and the Cochrane Library. Only randomised studies comparing regional and general anaesthesia for total hip or knee replacement were included. We identified 21 independent, randomised clinical trials. A random-effects model was used to calculate all effect sizes. Pooled results from these trials showed that regional anaesthesia reduces the operating time (odds ratio (OR) -0.19; 95% confidence interval (CI) -0.33 to -0.05), the need for transfusion (OR 0.45; 95% CI 0.22 to 0.94) and the incidence of thromboembolic disease (deep-vein thrombosis OR 0.45, 95% CI 0.24 to 0.84; pulmonary embolism OR 0.46, 95% CI 0.29 to 0.80). Regional anaesthesia therefore seems to improve the outcome of patients undergoing total hip or knee replacement.

Multimodal pain management after total hip and knee arthroplasty at the Ranawat Orthopaedic Center

Improvements in pain management techniques in the last decade have had a major impact on the practice of total hip and knee arthroplasty (THA and TKA). Although there are a number of treatment options for postoperative pain, a gold standard has not been established. However, there appears to be a shift towards multimodal approaches using regional anesthesia to minimize narcotic consumption and to avoid narcotic-related side effects. Over the last 10 years, we have used intravenous patient-controlled analgesia (PCA), femoral nerve block (FNB), and continuous epidural infusions for 24 and 48 hours with and without FNB. Unfortunately, all of these techniques had shortcomings, not the least of which was suboptimal pain control and unwanted side effects. Our practice has currently evolved to using a multimodal protocol that emphasizes local periarticular injections while minimizing the use of parenteral narcotics. Multimodal protocols after THA and TKA have been a substantial advance; they provide better pain control and patient satisfaction, lower overall narcotic consumption, reduce hospital stay, and improve function while minimizing complications. Although no pain protocol is ideal, it is clear that patients should have optimum pain control after TKA and THA for enhanced satisfaction and function.

LEVEL OF EVIDENCE

Level V, expert opinion. See the Guidelines for Authors for a complete description of levels of evidence.

Can epidural anesthesia and warfarin be coadministered?

Epidural hypotensive anesthesia can, in addition to imparting numerous intraoperative benefits, provide excellent postoperative pain control for patients having joint arthroplasties. However, because of the risk of epidural hematoma, epidural anesthesia is not coadministered with anticoagulation in some centers. We retrospectively ascertained, by chart review, the incidence of epidural hematoma in 11,235 patients having 12,991 knee arthroplasties at our institution who received oral anticoagulation and epidural anesthesia for their surgery. Warfarin was administered on the day of surgery. With the exception of 212 patients, the epidural catheter was removed within 48 hours of surgery. Based on clinical examinations, we detected no epidural hematomas. For 1030 patients (1038 knees) whose charts were reviewed in detail, the mean international normalized ratio at the time of removal of the epidural catheter was 1.54 (range, 0.93-4.25). We identified no other complications related to the coadministration of epidural anesthesia and warfarin. Although administration of epidural anesthesia in patients with coagulopathy can be detrimental, we recognized no cases of epidural hematoma causing neurologic symptoms in patients receiving controlled oral anticoagulation after total knee arthroplasty.

Effect on deep venous thrombosis with flexion during total knee arthroplasty

This study investigates the relationship between intraoperative extreme flexion and tibia-femoral dislocation during total knee arthroplasty on the prevalence of postoperative deep venous thrombosis. Knees were randomized into two groups. The control group underwent the procedure according to normal protocol, which kept the knee in extreme flexion and maintained dislocation for the duration of the exposure, whereas the variable group underwent the procedure modified to minimize the total amount of time the knee was hyperflexed and dislocated. Venograms were positive in 42% (39/92) of the control knees and 38% (30/79) of the modified group (p = 0.6). Proximal deep venous thrombosis were found in 12% (11/92) of the control knees and in 16% (13/79) of the modified knees (p = 0.4). No statistical difference could be detected between the two techniques in regards to the incidence of deep venous thrombosis.

The epidemiology of venous thromboembolism in the community: implications for prevention and management

The epidemiology of venous thromboembolism (VTE) in the community has important implications for VTE prevention and management. This review describes the incidence, survival, recurrence, complications and risk factors for deep vein thrombosis and pulmonary embolism occurring in the community. VTE incidence among whites of European origin exceeds 1 per 1000; the incidence among persons of African and Asian origin may be higher and lower, respectively. VTE incidence over recent time remains unchanged. Survival after VTE is worse than expected, especially for pulmonary embolism where one-quarter of patients present as sudden death. Of those patients who survive, 30% develop VTE recurrence and venous stasis syndrome within 10 and 20 years, respectively. Common independent VTE risk factors include surgery, hospitalization for acute medical illness, nursing home confinement, trauma, active cancer, neurologic disease with extremity paresis, superficial vein thrombosis, central venous catheter/transvenous pacemaker, and among women, oral contraceptives, pregnancy and the puerperium, and hormone and SERM therapy. Exposures can identify populations at risk but have a low predictive value for the individual person. An acquired or familial thrombophilia may predict the subset of exposed persons who actually develop symptomatic VTE. In conclusion, VTE is a common, lethal disease that recurs frequently and causes serious long-term complications. To improve survival and prevent complications, VTE occurrence must be reduced. Better individual risk stratification is needed in order to modify exposures and target primary and secondary prophylaxis to the person who would benefit most.

Safety of one-stage bilateral hip and knee arthroplasties under regional anaesthesia and routine anaesthetic monitoring

Using a computer-based quality assurance program, we analysed peri-operative data on 160 patients undergoing one-stage bilateral hip or knee arthroplasties under regional anaesthesia with routine anaesthetic monitoring and only using peripheral intravenous access for peri-operative safety. We monitored defined intra-operative adverse events such as hypotension, myocardial ischaemia, arrhythmias, hypovolaemia, hypertension and early post-operative complications. We also determined post-operative hip and knee function, and patient satisfaction with different aspects of the anaesthetic management. Those patients undergoing one-stage bilateral arthroplasties were matched according to a cross-stratification which used three variables (American Society of Anesthesiologists’ physical status scoring system, age and joint replaced) to patients undergoing unilateral hip or knee arthroplasties. Serious intra-operative adverse events were, with the exception of intra-operative hypotension, very infrequent in patients undergoing bilateral (nine adverse events) as well as unilateral arthroplasties (five adverse events). Early post-operative complications were also infrequent in both groups. However, the risks of receiving a heterologous blood transfusion (odds ratio 2.5; 95% confidence interval (CI) 1.3 to 5.0, estimated by exact conditional logistic regression) or vasoactive drugs (odds ratio 3.9; 95% CI 2.0 to 7.8) were significantly greater for patients undergoing bilateral operations. Patient satisfaction with anaesthesia was high; all patients who underwent the one-stage bilateral operation would choose the same anaesthetic technique again.

Venous thromboembolism: disease burden, outcomes and risk factors

The epidemiology of venous thromboembolism (VTE) in the community has important implications for VTE prevention and management. This review describes the disease burden (incidence), outcomes (survival, recurrence and complications) and risk factors for deep vein thrombosis and pulmonary embolism occurring in the community. Recent comprehensive studies of the epidemiology of VTE that reported the racial demography and included the full spectrum of disease occurring within a well-defined geographic area over time, separated by event type, incident vs. recurrent event and level of diagnostic certainty, were reviewed. Studies of VTE outcomes had to include a relevant duration of follow-up. VTE incidence among whites of European origin exceeded 1 per 1000; the incidence among persons of African and Asian origin may be higher and lower, respectively. VTE incidence over recent time remains unchanged. Survival after VTE is worse than expected, especially for pulmonary embolism. Thirty percent of patients develop VTE recurrence and venous stasis syndrome. Exposures can identify populations at risk but have a low predictive value for the individual. An acquired or familial thrombophilia may predict the subset of exposed persons who actually develop symptomatic VTE. In conclusion, VTE is a common, lethal disease that recurs frequently and causes serious long-term complications. To improve survival and prevent complications, VTE occurrence must be reduced. Better individual risk stratification is needed in order to modify exposures and target primary and secondary prophylaxis to the person who would benefit most.

Risk factors for venous thromboembolism

Venous thromboembolism is a common and potentially lethal disease. Patients who have pulmonary embolism are at especially high risk for death. Death owing to pulmonary embolism is independent of other comorbid conditions (e.g., cancer, chronic heart disease, or lung disease). Sudden death is often the first clinical manifestation. Only a reduction in the incidence of venous thromboembolism can reduce sudden death owing to pulmonary embolism and venous stasis syndrome owing to deep vein thrombosis. The incidence of venous thromboembolism has been relatively constant since about 1980. Improvement in the incidence of venous thromboembolism will require better recognition of persons at risk, improved estimates of the magnitude of risk, the avoidance of risk exposure when possible, more widespread use of safe and effective prophylaxis when risk is unavoidable, and targeting of prophylaxis to those persons who will benefit most. Recognition of venous thromboembolism as a multifactorial disease with genetic and genetic-environmental interaction has provided significant insights into its epidemiology and offers the possibility of improved identification of persons at risk for incident and recurrent venous thromboembolism.

Comprehensive deep venous thrombosis prevention strategy after total-knee arthroplasty

OBJECTIVE

Venous thromboembolism after total-knee arthroplasty represents a common early postoperative complication resulting in significant morbidity. Despite this, the optimal prophylactic regimen is controversial. The prevalence of venous thromboembolism has been cited as high as 35% in patients receiving pharmacologic prevention alone. We investigated the efficacy of a comprehensive prevention protocol encompassing the use of epidural anesthesia, aspirin, venous foot compression pumps, and early mobilization in a series of consecutive total-knee arthroplasties.

DESIGN

A series of 100 consecutive total-knee arthroplasty patients were enrolled into the prospective trial. All patients were allowed full weight bearing on the first postoperative day and ambulation as tolerated. Venous foot compression pumps and aspirin were used immediately after surgery in the totality of subjects. Seventy-five percent of the patients were transferred to an acute rehabilitation service during the first postoperative week. The presence of deep-vein thrombosis was subsequently determined with the routine use of venous duplex scans.

RESULTS

Three patients (3%) demonstrated evidence of distal deep-vein thrombosis. No patient had symptomatic pulmonary embolism.

CONCLUSION

The combination of epidural anesthesia, aspirin, immediate postoperative venous foot compression pumps, and early ambulation together seem to be a more effective approach to prevent the occurrence of thromboembolic events after knee replacements than pharmacologic prevention alone.

A multimodality regimen for deep venous thrombosis prophylaxis in total knee arthroplasty

Data indicate that deep venous thrombosis (DVT) occurs at the time of knee arthroplasty. Nevertheless, literature concerning DVT prophylaxis has only recently addressed this contention. This prospective study evaluated the efficacy of a perioperative prophylactic regimen. Between January 1996 and June 2001, 1,308 knees (964 surgeries) underwent total knee arthroplasty. Patients were treated routinely with intraoperative heparin (1000 units intravenous push before inflation of the tourniquet and 500 units at deflation), hypotensive epidural anesthesia (MAP 70-90), external pneumatic compression boots, and aspirin (325 mg, PO, BID for 6 weeks). Duplex venous ultrasonography was performed before discharge. DVT was detected in 4% of cases (1% proximal and 3% distal). Bleeding complications occurred in 1%, and perioperative medical complications occurred in 12%.

Respiratory complications associated with anesthesia

Adverse pulmonary outcomes that follow anesthesia and surgery are often attributed to anesthesia care. PPCs are a significant concern for anesthesia caregivers because they use drugs and techniques that temporarily decrease lung volume, impair airway reflexes, limit immune function, and depress secretion mobilization. A significant component of perioperative risk derives from the surgical site, postoperative pain, and effects of pharmacologic pain management. Rapidly evolving surgical and anesthesia techniques and the introduction of newer pharmaceutical agents make it difficult to identify best practice from retrospective experience reported in the perioperative literature. Prospective studies that deal with specific patient populations, incomparable patient groups or techniques, and unique practice bias have limited validity of claims regarding several promising approaches to perioperative risk reduction. In the absence of clear scientific principles, a perioperative pulmonary risk management strategy for the early part of this century is based on the consensus practice of informed clinicians (Box 4).

Surveillance for venous thromboembolic disease after total knee arthroplasty

The value of deep venous thrombosis screening after total knee arthroplasty is controversial. The purpose of the current study was to examine the value of routine surveillance for venous thrombosis after total knee arthroplasty done with modern operative and perioperative treatment. Computerized search engines were used to identify papers published between 1985 and July 2000 relevant to the purpose of the study. Papers that met the inclusion criteria for review were categorized as follows: the frequency of deep venous thrombosis; the natural history of deep venous thrombosis; the accuracy of screening methods for venous thrombosis; and efficacy of screening in reducing morbidity attributable to venous thromboembolism after total knee arthroplasty. Several studies have shown a low complication rate related to venous thromboembolic disease when compression ultrasound is used for screening as part of a clinical algorithm after knee arthroplasty. However, the only large prospective randomized trial evaluating ultrasound screening failed to show a reduction in morbidity with a surveillance protocol. The benefits of surveillance depend on factors specific to each surgeon's practice including the type and duration of venous prophylaxis, the rate of symptomatic and asymptomatic thromboembolic disease associated with that protocol, and the accuracy of screening tests used for surveillance.

Nonpharmacologic thromboembolic prophylaxis in total knee arthroplasty

Deep venous thrombosis is the most common complication in patients having elective total knee replacement. Pneumatic compression devices play an important role in the prophylaxis of deep venous thrombosis and effectively decrease the risk of distal deep venous thrombosis. The combination therapy with pharmacologic agents has the benefit of decreasing the rate of proximal deep venous thrombosis and therefore is recommended. In the absence of clinical data, recent in vivo flow studies suggest that calf or combined foot and calf compression are superior to foot compression alone. Epidural anesthesia in comparison with general anesthesia decreases the incidence of thromboembolic disease after total knee arthroplasty. Although hypotensive anesthesia and intraoperative heparin have been proven to substantially lower the incidence of deep venous thrombosis after total hip arthroplasty, the current literature does not support its application during the implantation of a total knee replacement. Pneumatic compression devices are an important part of deep venous thrombosis prophylaxis especially in the early postoperative period considering that pharmacologic anticoagulation is contraindicated in the first 12 hours after spinal anesthesia and in the presence of an epidural line.

The Insall legacy in total knee arthroplasty

John N. Insall was a pioneer in the field of knee surgery. He was a rare individual who accomplished unparalleled levels of success as a surgeon, designer, and teacher. During the past 4 decades, he was instrumental in evolving total knee arthroplasty to its current state of excellence. Insall's impact on orthopaedics is felt by all who have come in contact with him.

Patient satisfaction and effectiveness of lumbar plexus and sciatic nerve block for total knee arthroplasty

The purpose of this study was to evaluate the efficacy of combined lumbar plexus block techniques for total knee arthroplasty. Long-acting local anesthetics were used to ensure adequate intraoperative and postoperative anesthesia and analgesia. All patients undergoing total knee arthroplasty at our institution were offered lumbar plexus block after obtaining informed consent. Patients for study were a continuous group of 87 patients over a 1-year period. A subset of 40 patients was studied for postoperative analgesia effect. All patients were contacted by phone for a satisfaction survey. There were 87 patients who received initial lumbar plexus and sciatic nerve blocks, 78% (68 of 87) of whom had adequate initial blocks. Sixteen patients (22%) required conversion to general anesthesia intraoperatively because of inadequate anesthesia. A subset of patients studied for postoperative analgesia revealed an average time of 13 hours before the first request for supplemental narcotics. There were no complications related to the lumbar plexus block in our study group of patients. There was a 92% overall satisfaction rate with the anesthesia provided by the lumbar plexus block. Lumbar plexus block can be used successfully for total knee arthroplasty. Lumbar plexus block appears to have advantages for early postoperative analgesia, leading to increased patient comfort and satisfaction.

Current trends in perioperative pain management

Wider use of optimized multimodal accelerated postoperative recovery programs require that anesthesiologists step out of traditional operating room anesthesia roles and even beyond current pain management consultant roles. Development of optimal postoperative recovery services requires close collaboration between anesthesiologists, surgeons, nurses, physical therapists, administrators, and others involved in the management of patients after surgery. Optimization of perioperative care is an ongoing process enhanced by clinical investigation; however, making significant improvements to clinical practice does not have to wait for additional research data, but should proceed now, with broader application of techniques known to enhance rehabilitation and recovery. Based on existing data, the challenges of developing perioperative recovery services seem likely to be rewarded with improved patient outcomes and reduced cost.

Influencing factors on perioperative morbidity in knee arthroplasty

In an unselected, prospective case control study, the incidence of risk factors and perioperative complications was investigated in 237 knees (203 patients) undergoing implantation of cementless total knee endoprostheses. Intraoperative complications and postoperative complications occurred in 84 patients (99 knees), with 61 specific orthopaedic complications in 50 patients (57 knees) and 74 nonsurgical complications in 55 patients (65 knees). The presence of cardiac, neurologic, or psychiatric concomitant diseases, advanced age, male gender, high-risk anesthesia scores, number and extent of intraoperative blood pressure fluctuations, and surgery under intubation anesthesia are associated significantly with the incidence of nonsurgical perioperative complications. In contrast, body weight, concomitant metabolic and circulatory diseases, previous surgery on the joint, origin of the articular disease, and the duration of surgery and tourniquet time do not correlate with the probability of a nonsurgical perioperative complication. A significant correlation with the parameters investigated could not be found for the occurrence of specific orthopaedic complications. The current report identifies specific risk factors that define patients with risk of having perioperative complications according to objective criteria. These parameters must be given individual consideration when establishing the indication and planning of surgery.