Coronary Artery Stents: II. Perioperative Considerations and Management

[Perioperative management of coagulation in otorhinolaryngologic surgery]

Considering the increasing number of patients suffering from drug-induced coagulation disorders caused by antiplatelet or anticoagulant therapy, the right balance between minimizing the risk of bleeding and the risk of a venous thrombosis or embolism during otorhinolaryngologic (ORL) surgery is becoming increasingly important. According to a recent study, the highest risk of intraoperative bleeding in ORL surgery is associated with transoral tumor surgery, tonsillectomy, thyroidectomy, and glomus tumor surgery. The risk of venous thrombosis or embolism during ORL surgery is estimated to be 1%, and increases to 6% among tumor patients. Currently, there is no general recommendation for perioperative hemostatic management because of the limited available data. In the majority of patients who continue antiplatelet therapy with acetylsalicylic acid (ASS) to prevent thromboembolic events, the perioperative bleeding risk is considered to be acceptable. For patients with dual antiplatelet therapy, surgical procedures should be only performed after adaption of the medication.

Preoperative echocardiogram does not increase time to surgery in hip fracture patients with prior percutaneous coronary intervention

BACKGROUND

The purpose of this study was to (1) assess the effect of preoperative echocardiogram on time to surgery and (2) assess the outcomes of patients with a previous percutaneous coronary intervention (PCI).

METHODS

Demographic, clinical, quality and cost data were obtained and a validated risk predictive tool (STTGMA) was calculated for each of a consecutive series of hip fracture patients. Comparative analyses of patients who had an echocardiogram prior to surgery or a PCI prior to hospitalization were performed.

RESULTS

Between 2014 and 2020, 2625 patients presented to our institution with a hip fracture. From this cohort 471 patients underwent a preoperative transthoracic echocardiogram (TTE), 30 who had a history of a PCI, and an additional 26 who had a history of PCI but did not undergo a preoperative TTE. Those undergoing a preoperative TTE had similar time (days) to surgery (1.73 vs 1.77, p = 0.86) and 30-day mortality (4% vs 7%, p = 0.545) regardless of PCI history. PCI patients who underwent a preoperative TTE experienced increased rates of 1-year mortality (27% vs 10%, p = 0.007) and major complications (23% vs 12%, p = 0.08) compared to those without a PCI history. PCI patients undergoing a preoperative TTE had a similar time (days) to surgery (1.77 vs 1.48, .p = 0.397) compared to PCI patients without a preoperative TTE. Patients who underwent a preoperative TTE had higher rates of 90-day readmission (31.0% vs 8.0%, p = 0.047) and 1-year mortality (26.7% vs 3.8%, p = 0.029).

CONCLUSIONS

Having a preoperative TTE does not affect surgical wait times in hip fracture patients regardless of PCI history, but it may not improve mortality outcomes or reduce postoperative complications in patients with a history of a PCI.

Effect of Routine Clopidogrel Use on Bleeding Complications After Endobronchial Ultrasound-guided Fine Needle Aspiration

BACKGROUND

Endobronchial ultrasonography has proven to be highly sensitive and specific in the diagnoses of patients with mediastinal and hilar adenopathy. Many of these patients are on a combination of clopidogrel (a compound that inhibits adenosine diphosphate-induced platelet aggregation) and aspirin due to neurological and/or cardiac-related comorbidities, and stopping anticoagulation may place these patients at high risk for potential complications. Our group has previously showed that thoracentesis with an 8-french catheter is safe in patients receiving clopidogrel and aspirin with low risk of complications. In this manuscript, we report the outcomes of the largest prospective multicenter series of patients undergoing endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) while receiving clopidogrel.

METHODS

Patients presenting to our institutions with mediastinal/hilar adenopathy, requiring EBUS-TBNA, and actively taking clopidogrel and aspirin were included in the study. If the medication could be held for 5 to 7 days before the procedure, the patient was excluded. EBUS-TBNA was performed by an interventional pulmonology faculty on a total of 42 patients. All patients received total intravenous anesthesia, and a total of 92 nodes were sampled. First, 3 passes were performed with a 22-G needle. If no complications were encountered, we followed with additional 3 passes with a 21 G. Rapid onsite evaluation was performed in all patients. Bleeding at the puncture site was considered significant if it required cold saline, topical sympathomimetic, or balloon tamponade for hemostasis. Bleeding was considered nonsignificant if no interventions were required to achieve hemostasis.

RESULTS

We were able to perform all procedures successfully using both the 21 and 22-G needles. One patient required 30 mL cold saline installation to accomplish hemostasis with the 21 and 22-G needles. Our yield was comparable with the current literature. No statistically significant complications occurred during the procedure. All patients were contacted within 24 hours, and none reported bloody sputum.

CONCLUSION

We suggest that EBUS-TBNA, using 22 and 21-G needles, is safe with high yields in patients with mediastinal/hilar adenopathy, actively taking clopidogrel and aspirin, and are at high risk for thrombotic complications if the medication is discontinued.

Patterns and Impact of Dual Antiplatelet Cessation on Cardiovascular Risk After Percutaneous Coronary Intervention in Patients With Acute Coronary Syndromes

The aim of this study was to examine the patterns and clinical impact of differing modes of dual-antiplatelet therapy (DAPT) cessation after percutaneous coronary intervention (PCI) in patients presenting with and without acute coronary syndromes (ACS). The PARIS (patterns of nonadherence to antiplatelet regimens in stented patients) registry was a multicenter study of 5,018 patients who underwent PCI. DAPT cessation was categorized as physician-recommended discontinuation, interruption, or disruption. Overall rates of 2-year DAPT discontinuation did not differ between non-ACS and ACS patients (38.8% vs 37.2%, p = 0.252). ACS patients were less likely to interrupt DAPT (8.5% vs 10.7% p<0.001), but were more likely to disrupt DAPT (16.4% vs 11.9%, p<0001). Adverse events after DAPT cessation were highest after disruption, intermediate with discontinuation, and lowest with interruption across both groups. Disruption of DAPT predicted MACE in both ACS patients (hazard ratio [HR] 2.89 [1.88 to 4.45; p<0.001]) and non-ACS patients (HR 2.08 [1.29 to 3.35; p = 0.002]). Interruption of DAPT predicated MACE in ACS patients (HR 2.72 [1.35 to 5.48]) but not in non-ACS patients (HR 0.44 [0.14 to 1.40]; p_interaction≤0.01). In conclusion, the incidence of DAPT cessation mode differs by presentation with or without ACS. Physician guided DAPT discontinuation was the most common mode of DAPT cessation and appears to be safe across both groups. There were higher rates of adverse events associated with the interruption of DAPT in ACS patients.

Comparison of the postoperative effect between epidural anesthesia and continuous wound infiltration on patients with open surgeries: A meta-analysis

PURPOSE

The study aimed to compare the effect of epidural anesthesia (EA) and continuous wound infiltration (CWI) on surgical patients.

METHODS

The literature retrieval was conducted in relevant databases from their inception to June 2018 with the predefined searching strategy and selection criteria. Then, the Cochrane Collaboration's tool was used to assess the quality of included studies. In addition, odds ratio (OR) and standardized mean difference (SMD) with its corresponding 95% confidence interval (CI) were used as a measure of effect size for evaluating outcomes indicators.

RESULTS

Totally, sixteen RCTs were included. The incidence of hypotension in EA group was significantly higher than CWI group (OR = 3.7398; 95% CI: 1.0632 to 13.1555). In addition, EA provided better pain relief than CWI on rest at 72 h (SMD = -0.6037; 95% CI: -1.0767 to -0.1308) after surgery. Additionally, there were no significant differences in pain score on rest and mobilization at 2 h, 12 h, 24 h and 48 h. Moreover, the subgroup analysis showed that pain scores in EA group was significantly reduced at 2 h on rest and 12 h on mobilization than CWI group after liver resection surgery, as well as at 72 h on rest after colorectal surgery.

CONCLUSION

CWI is superior to EA with a lower incidence of complications for use in surgery, and EA may provide better pain control than CWI on pain relief after surgery.

A retrospective study showing the extent of compliance with perioperative guidelines in patients with coronary stents with regard to double antiplatelet therapy

STUDY OBJECTIVE

To evaluate perioperative dual antiplatelet therapy management in patients with previously placed coronary stents.

DESIGN

Retrospective medical record review.

SETTING

Academic medical center.

PATIENTS

A total of 1891 surgical cases performed at Vanderbilt University Medical Center in 2012 were evaluated using a perioperative database. Of these, 161 had complete data records that were evaluated using 2 evidence-based and expert opinion-supported protocols.

INTERVENTIONS

N/A.

MEASUREMENTS

This study is meant to evaluate perioperative antiplatelet management decisions in patients with coronary stents.

MAIN RESULTS

Management decisions were consistent with guidelines regarding antiplatelet therapy in 13% (21/161) of patients. Of the 87% (140/161) of cases where decisions were not consistent, 88% (123/140) were due to discontinuing aspirin preoperatively when there was not a high risk of surgical bleeding.

CONCLUSIONS

This study revealed suboptimal adherence to current perioperative antiplatelet management guidelines in patients with coronary stents. The lack of adherence to current guidelines is concerning and could be used to support the notion of an anesthesiologist-led Perioperative Surgical Home.

Survival analysis for high-dimensional, heterogeneous medical data: Exploring feature extraction as an alternative to feature selection

BACKGROUND

In clinical research, the primary interest is often the time until occurrence of an adverse event, i.e., survival analysis. Its application to electronic health records is challenging for two main reasons: (1) patient records are comprised of high-dimensional feature vectors, and (2) feature vectors are a mix of categorical and real-valued features, which implies varying statistical properties among features. To learn from high-dimensional data, researchers can choose from a wide range of methods in the fields of feature selection and feature extraction. Whereas feature selection is well studied, little work focused on utilizing feature extraction techniques for survival analysis.

RESULTS

We investigate how well feature extraction methods can deal with features having varying statistical properties. In particular, we consider multiview spectral embedding algorithms, which specifically have been developed for these situations. We propose to use random survival forests to accurately determine local neighborhood relations from right censored survival data. We evaluated 10 combinations of feature extraction methods and 6 survival models with and without intrinsic feature selection in the context of survival analysis on 3 clinical datasets. Our results demonstrate that for small sample sizes - less than 500 patients - models with built-in feature selection (Cox model with ℓ1 penalty, random survival forest, and gradient boosted models) outperform feature extraction methods by a median margin of 6.3% in concordance index (inter-quartile range: [-1.2%;14.6%]).

CONCLUSIONS

If the number of samples is insufficient, feature extraction methods are unable to reliably identify the underlying manifold, which makes them of limited use in these situations. For large sample sizes - in our experiments, 2500 samples or more - feature extraction methods perform as well as feature selection methods.

Influence of catheter insertion on the hemodynamic environment in coronary arteries

Intravascular stenting is one of the most commonly used treatments to restore the vascular lumen and flow conditions, while perioperative complications such as thrombosis and restenosis are still nagging for patients. As the catheter with crimped stent and folded balloon is directly advanced through coronary artery during surgery, it is destined to cause interference as well as obstructive effect on blood flow. We wonder how the hemodynamic environment would be disturbed and weather these disturbances cause susceptible factors for those complications. Therefore, a realistic three-dimensional model of left coronary artery was reconstructed and blood flow patterns were numerically simulated at seven different stages in the catheter insertion process. The results revealed that the wall shear stress (WSS) and velocity in left anterior descending (LAD) were both significantly increased after catheter inserted into LAD. Besides, the WSS on the catheter, especially at the ending of the catheter, was also at high level. Compared with the condition before catheter inserted, the endothelial cells of LAD was exposed to high-WSS condition and the risk of platelet aggregation in blood flow was increased. These influences may make coronary arteries more vulnerable for perioperative complications.

Periarticular infiltration for pain relief after total hip arthroplasty: a comparison with epidural and PCA analgesia

PURPOSE

Epidural and intravenous patient-controlled analgesia (PCA) are established methods for pain relief after total hip arthroplasty (THA). Periarticular infiltration is an alternative method that is gaining ground due to its simplicity and safety. Our study aims to assess the efficacy of periarticular infiltration in pain relief after THA.

METHODS

Sixty-three patients undergoing THA under spinal anaesthesia were randomly assigned to receive postoperative analgesia with continuous epidural infusion with ropivacaine (epidural group), intraoperative periarticular infiltration with ropivacaine, clonidine, morphine, epinephrine and corticosteroids (infiltration group) or PCA with morphine (PCA group). PCA morphine provided rescue analgesia in all groups. We recorded morphine consumption, visual analog scale (VAS) scores at rest and movement, blood loss from wound drainage, mean arterial pressure (MAP) and adverse effects at 1, 6, 12, 24 h postoperatively.

RESULTS

Morphine consumption at all time points, VAS scores at rest, 6, 12 and 24 h and at movement, 6 and 12 h postoperatively were lower in infiltration group compared to PCA group (p < 0.05), but did not differ between infiltration and epidural group. There was no difference in adverse events in all groups. At 24 h, MAP was higher in the PCA group (p < 0.05) and blood loss was lower in the infiltration group (p < 0.05).

CONCLUSIONS

In our study periarticular infiltration was clearly superior to PCA with morphine after THA, providing better pain relief and lower opioid consumption postoperatively. Infiltration seems to be equally effective to epidural analgesia without having the potential side effects of the latter.

Patients with ischemic heart disease

Ischemic heart disease (IHD) occurs when myocardial oxygen supply is not adequate for myocardial oxygen demand. Patients with IHD who are undergoing surgery are at risk for development of perioperative cardiac events (PCEs), and this risk depends on the type of surgery, the presence of clinical risk factors, and functional status of the patients. Appropriate perioperative management of medications such as dual antiplatelet therapy and β-blockers has a significant impact on outcomes. Perioperative management decisions should be communicated clearly between the surgeon, cardiologist, and anesthesiologist in charge of the patient. Appropriate perioperative management reduces the incidence of PCEs.

Questions and answers on proper peri-operative management of antiplatelet therapy after coronary stent implantation to prevent stent thrombosis

Stent thrombosis (ST) is a rare but life-threatening complication of coronary artery stenting. Although dual-antiplatelet therapy is an effective management strategy in reducing the risk for ST, some patients may need to interrupt their regimens because of unforeseen circumstances, such as the requirement for surgery. In conclusion, this case presentation highlights some pertinent issues related to ST, including its risk factors, the perioperative management of antiplatelet agents, and treatment for ST.

Patients who require non-cardiac surgery in acute coronary syndrome

The coexistence of an acute coronary syndrome (ACS) and non-cardiac surgery (NCS) in an individual patient can be summarized in two challenging clinical scenarios for the treating physician: 1) Post-operative patients who develop ACS and 2) Patients with ACS who subsequently require NCS. Both settings are characterized by a struggle on the part of treating physicians attempting to optimize antithrombotic therapies for ACS while minimizing post-surgical bleeding risk. In this review we address specific clinical issues related to patients with coexistent NCS and ACS, discussing possible management strategies balancing ischemic and bleeding risk in these complex patient scenarios.

Effect of routine clopidogrel use on bleeding complications after ultrasound-guided thoracentesis

BACKGROUND

Thoracentesis is one of the most commonly performed medical procedures with an excellent safety profile. Clopidogrel (a compound that inhibits adenosine diphosphate-induced platelet aggregation) is often prescribed for primary or secondary prevention of cardiovascular disease and has been associated with bleeding complications in patients undergoing surgical procedures. The purpose of this study was to assess the safety of ultrasound (US)-guided thoracentesis in patients receiving clopidogrel therapy.

METHODS

Data were collected on 30 consecutive patients taking clopidogrel without other known underlying coagulation problems. These patients underwent 45 US-guided thoracenteses over 26 months. Clopidogrel was not discontinued before the thoracentesis in patients presenting with symptomatic pleural effusion. Thoracenteses were performed in these patients and the incidence of bleeding and other complications among patients was reported.

RESULTS

Between June 2009 and August 2011, there were 30 consecutive patients on clopidogrel at the time of thoracenteses. These patients presented with respiratory distress because of pleural effusion and underwent a total of 45 thoracenteses. There was no significant bleeding or other complications in this patient population. No patient required transfusion after the procedure.

CONCLUSION

Patients who are receiving clopidogrel and present with symptomatic pleural effusion can safely undergo US-guided thoracentesis without interrupting clopidogrel before the procedure. Larger studies are required to confirm these results.

What would surgeons like from materials scientists?

Surgery involves the repair, resection, replacement, or improvement of body parts and functions and in numerous ways, surgery should be considered human engineering. There are many areas in which surgical materials could be improved, but surgeons are generally unaware of materials available for use, while materials scientists do not know what surgeons require. This article will review some of the areas where surgeons and materials scientists have interacted in the past and will discuss some of the most pressing problems which remain to be solved. These include better implant materials for hernia repair, breast reconstruction, the treatment of diabetes, vascular stenting and reconstruction, and electrical pacing devices. The combination of tissue engineering and nanomaterials has great potential for application to nearly every aspect of surgery. Tissue engineering will allow cells or artificial organs to be grown for specific uses while nanotechnology will help to ensure maximal biocompatibility. Biosensors will be combined with improved electrodes and pacing devices to control impaired neurological functions.

Painless myocardial ischemia is associated with mortality in patients with chronic kidney disease

BACKGROUND

Painless myocardial ischemia (PMI) is associated with poor outcomes in the general population. We hypothesized that the presence of PMI is inversely related to the level of kidney function and is associated with impaired survival in chronic kidney disease (CKD).

METHODS

A total of 356 patients who underwent percutaneous coronary intervention were assessed for PMI, which was defined as the absence of chest pain in response to balloon dilation of the affected vessel. Cox proportional hazards analysis was used to calculate 10-year all-cause mortality.

RESULTS

There was an increase in PMI occurrence by strata of estimated glomerular filtration rate (eGFR), whereby PMI was present in only 20.6% of individuals with eGFR ≥ 90 ml/min/1.73 m(2), but was found in 50.0% of individuals with eGFR <30 ml/min/1.73 m(2) (p = 0.004 for trend). Classification of individuals as having either CKD or PMI showed significant differences in adjusted mortality between groups (p < 0.001 for trend), with individuals having both CKD and PMI demonstrating the highest 10-year mortality. Compared to individuals with neither CKD nor PMI, individuals with CKD and no PMI had a hazard ratio (HR) for mortality of 1.64 (95% CI: 1.03-2.63, p = 0.038), while individuals with both PMI and CKD had an HR of 2.08 (1.30-3.33, p = 0.002).

CONCLUSION

PMI is common in the CKD population, is inversely related to the level of eGFR, and confers a substantially increased risk in CKD. These findings may partially explain the high mortality traditionally attributed to cardiovascular disease in CKD patients.

The creation and impact of a dedicated section on quality and patient safety in a clinical academic department

Optimizing the effectiveness, efficiency, integration, and satisfaction associated with delivered health care is not only highly principled but also good business practice in an extremely competitive environment. Programs that foster quality improvement and patient safety efforts while also promoting a scholarly focus can generate the incentives and organizational recognition needed to make patient safety and quality improvement bona fide components of the academic mission. The authors describe the development, implementation, and results of a dedicated Section on Quality and Patient Safety (SQPS) within an academic anesthesiology department. Spearheaded by a physician champion and vigorously supported by the departmental chair, this SQPS engaged core leaders from the Department of Anesthesiology. This departmental quality and patient safety management team adopted quality improvement and performance improvement techniques that have been successfully used in other industries. The SQPS has gained support through data-driven results and reiterative promotion. Transparency and accountability have also been powerful motivators for achieving clinician buy-in and changing behavior. Since its inception in 2007, the SQPS has initiated or managed through to completion more than 25 quality and performance improvement projects, including an intraoperative corneal injury reduction program, a wrong-sided regional anesthesia procedure, a drug-eluting coronary stent protocol, and a practice-improvement initiative for resident physicians. The SQPS has not only robustly promoted a departmental culture of quality patient care and safety but also set the standard for other departments and stakeholders within the authors' health system.

Perioperative management of a patient with recently placed drug-eluting stents requiring urgent spinal surgery

Patients receiving drug-eluting coronary stents (DES) require antiplatelet therapy for at least 12 months to prevent stent thrombosis (ST), a potentially calamitous event. Since interruption of antiplatelet therapy is the greatest risk factor for ST, it is imperative that the decision to discontinue these agents be based on an accurate assessment of the patient's risk for bleeding complications. Individuals who are regarded as being at a high risk are those undergoing intracranial, spinal or intraocular surgeries. These patients require alternative agents during the perioperative period to minimize both their risk of perioperative thrombosis and intraoperative hemorrhage. We report the case of a woman who required spinal surgery 3 months after she underwent placement of two drug-eluting stents. The patient's clopidogrel was stopped 5 days prior to surgery and an infusion of eptifibatide was used to "bridge" antiplatelet therapy during the perioperative period. Postoperatively, anticoagulation therapy was reinstituted using aspirin with clopidogrel. This case serves as a successful example of bridging therapy using a short acting and gycoprotein (GP) IIb/IIIa inhibitor as a means of maintaining antiplatelet therapy during the perioperative period to minimize the risk of stent thrombosis and the risk of intraoperative bleeding.

Perioperative antiplatelet management in patients with coronary artery stenting

Coronary artery disease is the primary cause of mortality in men and women in the United States. Transcatheter coronary intervention is the mainstay of treatment for patients with acute coronary artery disease presentations and patients with stable disease. Although percutaneous intervention initially only included balloon angioplasty, it now typically involves the placement of intracoronary stents. To overcome the limitations of bare-metal stents, namely in-stent restenosis, stents have been developed that remove pharmaceuticals that reduce neointimal hyperplasia and in-stent restenosis. However, these pharmaceutical agents also delay stent endothelialization, posing a prolonged risk of in situ thrombosis. Placement of an intracoronary stent (eg, bare-metal or drug-eluting stent) requires dual antiplatelet therapy to prevent the potentially life-threatening complication of stent thrombosis. The optimal duration of dual antiplatelet therapy following stent placement is unknown. This article discusses the factors to be considered when deciding when dual antiplatelet therapy can be safely discontinued. Unfortunately, in the hospital setting, this decision to interrupt dual antiplatelet therapy frequently must be made shortly after stent placement because of unanticipated surgical procedures or other unforeseen complications. The decision of when dual antiplatelet therapy can be safely interrupted needs to be individualized for each patient and involves factoring in the type of stent; the location and complexity of the lesion stented; post-stent lesion characteristics; the amount of time since stent placement; and the antiplatelet regimen currently in use, along with its implication for bleeding during the proposed procedure. Having a protocol in place, such as the protocol described in this article, can help guide this decision-making process and avoid confusion and potential error.

The perioperative management of patients with coronary artery stents: surveying the clinical stakeholders and arriving at a consensus regarding optimal care

BACKGROUND

The perioperative management of patients with a coronary artery stent is a major patient safety issue currently confronting clinicians. Surgery on a patient on antiplatelet therapy creates the following dilemma: is it better to withdraw the drugs and reduce the hemorrhagic risk or to maintain them and reduce the risk of a myocardial ischemic event?

METHODS

An electronic survey was used to sample a cross-section of local clinicians regarding the perioperative management of patients with an indwelling coronary artery stent. The reiterative Consensus-Oriented Decision-Making model was applied by an institutional task force with representation from anesthesiology, cardiology, primary care medicine, and surgery.

RESULTS

Significant disagreement existed among the multidisciplinary survey respondents regarding various aspects of the perioperative management of patients with indwelling coronary artery stents.

CONCLUSIONS

We clarified the perioperative risk factors for coronary stent thrombosis and an alternate process for immediate access to a cardiac catheterization laboratory at our institution.

The management of anticoagulants perioperatively

Perioperative management of anticoagulants requires one to balance the patient's risk factors for operative bleeding, the type of operation to be performed, and the patient's risk of thromboembolism. At present, no set algorithm exists for the perioperative management of all the anticoagulants. In this article, we address the perioperative management of the most commonly used anticoagulants seen in practice today, such as warfarin, heparin, dabigatran, clopidogrel, and aspirin, for the most commonly performed general thoracic operations.

Intracranial stents for treatment of acute ischemic stroke: evolution and current status

BACKGROUND

Intravascular stents have been applied to treat a variety of pathophysiologic conditions. With advances in stent design and delivery, stenting has become a viable treatment option in neurovascular disease. Recently, intracranial arterial stenting has received increasing interest as a modality to rapidly and effectively recanalize affected vessels in the setting of acute ischemic stroke.

METHODS

To examine the potential of stenting procedures for stroke, we compiled and analyzed relevant experimental and clinical studies in the available databases.

RESULTS

Our resulting discussion covers the brief history of stents, from their initial inception in the 1960s, to the developments of interventional cardiology, and finally to the treatment of acute occlusions of the neurovasculature. We also detail technological advances that have improved stent delivery to intracranial arteries and review the several clinical studies that feature stenting for the treatment of acute ischemic stroke.

CONCLUSION

Numerous clinical studies have revealed that stents are a quick and efficacious endovascular tool for acute ischemic stroke treatment. It appears likely that issues regarding design, safety, and feasibility of stent-based devices will experience further improvement and refinement, and from fruitful criticism of existing technologies and techniques, along with lessons from past mistakes, will arise safer and more effective devices.

Coronary stent management in elective genitourinary surgery

What's known on the subject? and What does the study add? Withdrawal of dual antiplatelet therapy before the recommended, 12 months for drug-eluting stents and 1 month for bare-metal stents increases the rate of major adverse coronary events and mortality. However, in those undergoing surgery the risk of bleeding is increased substantially for those on antiplatelet agents. Successful management in patients with coronary stents who must undergo elective or non-elective urological surgery should be a multidisciplinary decision. This article reviews the literature and recommends a protocol for clinical management of patients undergoing urological procedures after coronary stent placement. To review the literature on coronary stents and genitourinary surgery and provide a protocol for perioperative. The keywords, 'elective surgery', 'aspirin', 'clopidogrel', 'guidelines for percutaneous coronary intervention', and 'antiplatelet therapy after coronary stent placement' were used to search PubMed for any relevant articles relating to coronary stents. Recommendations were made based on the whether the procedures patients were exposed to placed them at low-, moderate- or high-bleeding risk based on the extent of the procedure. All elective procedures should be delayed for 1 month after bare-metal stent placement and 1 year after drug-eluting stent placement. In patients classified as low risk (endoscopy and laser prostatectomy), aspirin should be continued throughout the perioperative period and dual antiplatelet therapy should continue 24-48 h postoperatively, if there is no concern for active bleeding. In those classified as moderate risk (scrotal procedures, transurethral resection of bladder tumours, transurethral resection of the prostate, urinary sphincter placement) dual antiplatelet therapy should be discontinued 5-7 days before the procedure and continued within 7 days after procedure, if there is no concern for active bleeding, in consultation with cardiology. In high-risk procedures (cystectomy, nephrectomy, prostatectomy, penile prosthesis placement) dual antiplatelet therapy should be discontinued 10 days before the procedure and continued postoperatively within 7-10 days of the procedure, when there is no longer a concern for active bleeding with the assistance of a cardiologist. Coronary artery disease is becoming more prominent in our society, increasing the use of coronary stents and antiplatelet agents. With the proposed protocol, it is safe to proceed with surgical intervention in those that have adequate stent endothelialisation.

Antiplatelet therapy in ENT surgery: a review

INTRODUCTION

Antiplatelet agents such as aspirin and clopidogrel are increasingly encountered in clinical practice. Otorhinolaryngological surgeons are involved in the peri-operative decision of whether to continue treatment and risk haemorrhage or to discontinue treatment and risk thrombosis.

METHODS

Literature relating to the risk of spontaneous or operative haemorrhage was reviewed. The morbidity and mortality associated with cessation of agents was evaluated. Published guidelines were also evaluated. A protocol for the management of antiplatelet agents in the peri-operative period, with particular reference to ENT operations, is presented.

CONCLUSION

SIGNIFICANT morbidity and mortality is associated with the premature cessation of antiplatelet agents. Data from cardiac surgery suggest that operative blood loss only marginally increases in patients on aspirin and clopidogrel. However, the management of antiplatelet agents in the peri-operative period should be made after multidisciplinary consultation.

Perioperative management of patients on clopidogrel (Plavix) undergoing major lung resection

BACKGROUND

Management of patients requiring antiplatelet therapy with clopidogrel (Plavix) and major lung resection must balance the risks of bleeding and cardiovascular events. We reviewed our experience with patients treated with clopidogrel perioperatively to examine outcomes, including results of a new strategy for high-risk patients.

METHODS

Patients who underwent major lung resection and received perioperative clopidogrel between January 2005 and September 2010 were reviewed. Initially, clopidogrel management consisted of discontinuation approximately 5 days before surgery and resumption immediately after surgery. After July 2010, high-risk patients (drug-eluting coronary stent placement within prior year or previous coronary event after clopidogrel discontinuation) were admitted 2 to 3 days preoperatively and bridged with the intravenous glycoprotein IIb/IIIa receptor inhibitor eptifibatide (Integrilin) according to a multidisciplinary cardiology/anesthesiology/thoracic surgery protocol. Outcomes were compared with control patients (matched for preoperative risk factors and extent of pulmonary resection) who did not receive perioperative clopidogrel.

RESULTS

Fifty-four patients who had major lung resection between January 2005 and September 2010 and received clopidogrel perioperatively were matched with 108 control subjects. Both groups had similar mortality, postoperative length of stay, and no differences in the rates of perioperative transfusions, reoperations for bleeding, myocardial infarctions, and strokes. Seven of the 54 clopidogrel patients were admitted preoperatively for an eptifibatide bridge. Two of these patients received perioperative transfusions, but there were no deaths, reoperations, myocardial infarctions, or stroke.

CONCLUSIONS

Patients taking clopidogrel can safely undergo major lung resection. Treatment with an eptifibatide bridge may minimize the risk of cardiovascular events in higher risk patients.

Paclitaxel coated balloons for coronary artery interventions: a comprehensive review of preclinical and clinical data

After the "mechanical era" in interventional cardiology (represented by balloon angioplasty and bare metal stent implantation), arrived the "local dispensing" era, began with the intracoronary delivery of antithrombotic or antirestenotic drugs. However, even drug eluting stents have some pitfalls and cannot be used in all clinical subsets. In this article we will review the significant data on the paclitaxel-coated balloons for the treatment of coronary artery disease. Particularly, we will review the rationale of this new treatment strategy, the preclinical data and will focus on available clinical studies in humans. After the initial boost of the paclitaxel coated balloons with the Paccocath technology in in-stent restenotic lesions, the experimentation of newer devices in native coronary arteries raised some concerns on their efficacy and safety. We will comment on this topic trying to understand the reasons of this failure, and will discuss on possible future developments and applications for these devices for the treatment of coronary artery disease.

Intraoperative thrombosis of right coronary artery drug-eluting stent after 2 years of dual antiplatelet therapy

This study presents the case of intraoperative thrombosis of a right coronary drug-eluting stent and subsequent right heart ischemia more than 2 years poststent placement and after recent withdrawal of clopidogrel therapy. Dual antiplatelet therapy had been continued uninterrupted since placement until 7 days prior to surgery when clopidogrel was stopped. This case highlights the emerging evidence that drug-eluting stents are susceptible to late occlusive thrombosis on acute withdrawal of antiplatelet therapy. Right heart ischemia resolved with rapid intraoperative management and emergent cardiac catheterization. This emphasizes the necessity of immediate availability to cardiac interventional facilities, which can influence outcomes.

Anticoagulants: newer ones, mechanisms, and perioperative updates

With a growing number of new anticoagulant/antiplatelet agents being developed, it is likely that an increasing number of patients taking these drugs will present for surgery and other procedures. A familiarity with mechanisms of action and drug interactions helps to maintain optimal patient safety in the perioperative period. Furthermore, it is crucial for anesthesiologists to remain current on recommendations regarding discontinuation or need to continue the newer anticoagulants/antiplatelet drugs in patients presenting for surgery and/or regional anesthesia. Further studies are needed for monitoring of many of these newer agents and to identify antidotes.

General thoracic surgery is safe in patients taking clopidogrel (Plavix)

BACKGROUND

The objective of this study was to assess the safety of general thoracic surgery in patients taking antiplatelet (clopidogrel) therapy.

METHODS

A prospective study was conducted of consecutive patients who underwent general thoracic surgery and who were taking clopidogrel perioperatively. They were matched using a propensity score from our prospective database of 11,768 patients. Intraoperative and postoperative outcomes were compared.

RESULTS

Between January 2009 and April 2010 there were 33 patients on clopidogrel at the time of surgery and 132 controls. The most common procedures were thoracotomy with lobectomy in 11 patients (robotic in 1), video-assisted wedge resection in 6, mediastinoscopy in 4, and Ivor Lewis esophagogastrectomy in 2. Epidurals were not used. There was no intraoperative morbidity or bleeding in primary thoracotomy; however, 2 of the 4 patients who underwent redo thoracotomy had bleeding that required transfusions. None of the 8 patients receiving clopidogrel who had a coronary artery stent and underwent lobectomy had a perioperative myocardial infarction whereas 5 of the 14 control patients undergoing lobectomy who had a coronary artery stent did (P = .05). Otherwise, morbidity, mortality, and length of stay were no different.

CONCLUSIONS

Patients who are receiving clopidogrel and who have a coronary artery stent placed can safely undergo general thoracic surgery. The widely held belief that surgery cannot be performed without bleeding is untrue. This new finding not only eliminates much of the preoperative dilemma posed by these patients but also may reduce their risk of a postoperative myocardial infarction. However, patients who require a redo thoracotomy may be at increased risk of bleeding.

The Management of Antiplatelet Therapy in Patients With Coronary Stents Undergoing Noncardiac Surgery

Whereas the development of coronary stents has been a major breakthrough in the treatment of coronary artery disease, stent thrombosis, associated with myocardial infarction and death, has introduced a new challenge in the care of patients with coronary stents undergoing noncardiac surgery. This review presents the authors’ recommendations regarding the optimal management of such patients. Elective surgery should be postponed for at least 6 weeks and optimally 3 months for a bare-metal stent and at least 1 year for a drug-eluting stent. On the other hand, managing a patient undergoing non-elective surgery is more difficult and necessitates a case-by-case assessment of bleeding risk versus thrombotic risk based on patient comorbidities, type of stents present, details of the coronary intervention, and type of surgical procedure. Patients with a risk of bleeding that outweighs the risk of stent thrombosis should discontinue at least clopidogrel, whereas all other patients should continue dual antiplatelet therapy throughout the perioperative period.

Prevention of the renarrowing of coronary arteries using drug-eluting stents in the perioperative period: an update

The management of patients scheduled for surgery with a coronary stent, and receiving 1 or more antiplatelet drugs, has many controversies. The premature discontinuation of antiplatelet drugs substantially increases the risk of stent thrombosis (ST), myocardial infarction, and cardiac death, and surgery under an altered platelet function could also lead to an increased risk of bleeding in the perioperative period. Because of the conflict in the recommendations, this article reviews the current antiplatelet protocols after positioning a coronary stent, the evidence of increased risk of ST associated with the withdrawal of antiplatelet drugs and increased bleeding risk associated with its maintenance, the different perioperative antiplatelet protocols when patients are scheduled for surgery or need an urgent operation, and the therapeutic options if excessive bleeding occurs.

The management of patients on dual antiplatelet therapy undergoing orthopedic surgery

Cardiovascular disease is prevalent in patients undergoing orthopedic surgery. Many patients who have undergone previous percutaneous coronary intervention (PCI) with stenting are on dual antiplatelet therapy in order to minimize the risk of stent thrombosis. The optimal management of these patients in the perioperative setting remains unclear. We aim to provide information about the management of patients who have undergone a PCI with stents who are subsequently indicated for an orthopedic procedure. We will review the concerns from a cardiologist's and orthopedic surgeon's perspective in regards to the management of these patients in the perioperative setting. In addition, the current American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, and American College of Surgeons guidelines are reviewed. The decision to discontinue dual antiplatelet therapy in a patient who has undergone a PCI with stent should be made only after careful review of the risks for thrombosis and bleeding. Best practice suggests that these risks should be jointly assessed by the orthopedic surgeon and cardiologist. Those patients with stents at high risk of thrombosis should have surgery delayed if possible. There is little data supporting a significantly increased bleeding risk associated with mortality in orthopedic patients when antiplatelet therapy is continued perioperatively.

[Current aspects of anesthetic management in urological patients]

Patients with coronary stents should take clopidogrel and acetylsalicylic acid for 4 weeks or 12 months after stenting. Stopping this medication early, e.g., for surgery, results in a 90-fold increase in the patient's risk for myocardial infarction from stent thrombosis. The mortality due to perioperative acute coronary syndrome clearly exceeds that due to perioperative bleeding complications. If oral medication resulting in platelet inhibition has to be paused "bridging" with short-acting, intravenous GPIIb/IIIa antagonists is possible. In recent years perioperative beta-blockade has been recommended for patients with high coronary vascular risk, and recently also for those with medium or low risk. Current studies, however, indicate that patients on beta-blockers have increased perioperative mortality because of bradycardia, hypotension, and anemia. Therefore, anemia and hypotension should be rigorously avoided.Anesthetic management may have an influence on the postoperative course of cancer. Combined epidural-general anesthesia provides a benefit by minimizing the use of systemic opioids and volatile anesthetics. Presumably, this and a decreased response to surgical stress increase the ability of the patient's immune system to deal with cancer dissemination and micrometastasis.

Progress in platelet medicine: focus on stent thrombosis and drug resistance

The outcome importance of coronary stent thrombosis has mandated the careful management of these devices and their associated platelet blockade during the perioperative period. Recent trials have highlighted the catastrophic outcomes after stent thrombosis. The maintenance of clinically effective platelet blockade not only is essential to prevent stent thrombosis but also to optimize outcome in the integrated management of acute coronary syndromes. Dual antiplatelet blockade with aspirin and clopidogrel must balance the risks of ischemia and bleeding in patients with acute coronary syndromes, especially in the subset who require urgent surgical coronary revascularization. Platelet resistance to thienopyridines such as clopidogrel and prasugrel may be a significant risk factor for adverse cardiovascular outcomes. This phenomenon is detectable by point-of-care assays although standardized definitions and standardized testing batteries have yet to be formulated. The determinants of platelet resistance to thienopyridine therapy include genetic polymorphisms (especially related to hepatic drug metabolism) and drug interactions (especially the proton pump inhibitors). Novel platelet blockers are currently in late clinical development and will likely induce more consistent platelet blockade because of pharmacokinetic advantages including the lack of hepatic metabolism for activation. These agents will likely supersede clopidogrel and prasugrel if randomized trials show superior efficacy and clinical safety.

[Perioperative management of patients with coronary stents in non-cardiac surgery]

In patients with coronary stents scheduled for surgery the question arises whether and how antiplatelet therapy should be continued. Risks of perioperative bleeding and of acute stent thrombosis have to be considered simultaneously. The bleeding risk depends primarily on the kind of surgery and on patient comorbidity. The risk of stent thrombosis is increased in these patients due to the thrombogenic surface of the stents. The main determinants are hereby the time duration after stent implantation, the kind of the stent [uncoated (bare-metal stent, BMS) or coated (drug-eluting stent, DES)], as well as angiographic and clinical patient factors. Therefore, perioperative antiplatelet therapy has to be individually adapted for each patient. Bridging with heparin is ineffective. Bridging with intravenous antiplatelet drugs during the perioperative interruption of oral antiplatelet therapy might be a potential procedure in high-risk patients. Whether bedside monitoring of antiplatelet therapy improves the perioperative management of these patients and reduces adverse outcome is object of current studies.