Bivalirudin administration during percutaneous coronary intervention: emphasis on high-risk patients

Perioperative blood transfusion and blood conservation in cardiac surgery: the Society of Thoracic Surgeons and The Society of Cardiovascular Anesthesiologists clinical practice guideline

BACKGROUND

A minority of patients having cardiac procedures (15% to 20%) consume more than 80% of the blood products transfused at operation. Blood must be viewed as a scarce resource that carries risks and benefits. A careful review of available evidence can provide guidelines to allocate this valuable resource and improve patient outcomes.

METHODS

We reviewed all available published evidence related to blood conservation during cardiac operations, including randomized controlled trials, published observational information, and case reports. Conventional methods identified the level of evidence available for each of the blood conservation interventions. After considering the level of evidence, recommendations were made regarding each intervention using the American Heart Association/American College of Cardiology classification scheme.

RESULTS

Review of published reports identified a high-risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) preoperative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities. Careful review revealed preoperative and perioperative interventions that are likely to reduce bleeding and postoperative blood transfusion. Preoperative interventions that are likely to reduce blood transfusion include identification of high-risk patients who should receive all available preoperative and perioperative blood conservation interventions and limitation of antithrombotic drugs. Perioperative blood conservation interventions include use of antifibrinolytic drugs, selective use of off-pump coronary artery bypass graft surgery, routine use of a cell-saving device, and implementation of appropriate transfusion indications. An important intervention is application of a multimodality blood conservation program that is institution based, accepted by all health care providers, and that involves well thought out transfusion algorithms to guide transfusion decisions.

CONCLUSIONS

Based on available evidence, institution-specific protocols should screen for high-risk patients, as blood conservation interventions are likely to be most productive for this high-risk subset. Available evidence-based blood conservation techniques include (1) drugs that increase preoperative blood volume (eg, erythropoietin) or decrease postoperative bleeding (eg, antifibrinolytics), (2) devices that conserve blood (eg, intraoperative blood salvage and blood sparing interventions), (3) interventions that protect the patient's own blood from the stress of operation (eg, autologous predonation and normovolemic hemodilution), (4) consensus, institution-specific blood transfusion algorithms supplemented with point-of-care testing, and most importantly, (5) a multimodality approach to blood conservation combining all of the above.

Percutaneous coronary intervention: recommendations for good practice and training

Cardiologists undertaking percutaneous coronary intervention (PCI) are excited by the combination of patient and physician satisfaction and technological advance occurring on the background of the necessary manual dexterity. Progress and applicability of percutaneous techniques since their inception in 1977 have been remarkable; a sound evidence base coupled with the enthusiasm and ingenuity of the medical device industry has resulted in a sea change in the treatment of coronary heart disease (CHD), which continues to evolve at breakneck speed. This is the third set of guidelines produced by the British Cardiovascular Intervention Society and the British Cardiac Society. Following the last set of guidelines published in 2000, we have seen PCI activity in the UK increase from 33,652 to 62,780 (87% in four years) such that the PCI to coronary artery bypass grafting ratio has increased to 2.5:1. The impact of drug eluting stents has been profound, and the Department of Health is investigating the feasibility of primary PCI for acute myocardial infarction. Nevertheless, the changes in the structure of National Health Service funding are likely to focus our attention on cost effective treatments and will require physician engagement and sensitive handling if we are to continue the rapid and appropriate growth in our chosen field. It is important with this burgeoning development now occurring on a broad front (in both regional centres and district general hospitals) that we maintain our vigilance on audit and outcome measures so that standards are maintained for both operators and institutions alike. This set of guidelines includes new sections on training, informed consent, and a core evidence base, which we hope you will find useful and informative.

Safety of bivalirudin during percutaneous coronary interventions in patients with abnormal renal function

BACKGROUND

Chronic kidney disease is associated with an increased risk of ischemic and bleeding complications after percutaneous coronary intervention (PCI). Bivalirudin, a direct thrombin inhibitor, has been shown to reduce adverse bleeding events compared to unfractionated heparin in patients undergoing PCI. However, the effect of diminished renal function on the safety and efficacy of bivalirudin for PCI is unknown. We aimed to test the safety of bivalirudin in routine practice and to assess whether this benefit was influenced by renal function.

METHODS AND RESULTS

The interaction between renal impairment and benefit from bivalirudin was assessed in 115 consecutive patients (age 68.5+/-12.1, 45% female) undergoing PCI. Bivalirudin dosing was adjusted based on renal function. Creatinine clearance (CrCl) was calculated using the Cockroft-Gault formula. The composite endpoints of in-hospital death, myocardial infarction or revascularization and bleeding events were assessed. Overall, these events occurred in 10 (8.7%) patients. Patients with a CrCl<60 ml/min had a significantly increased risk for in-hospital complications (18.6 versus 2.78%, P = 0.011). Univariate analysis for MACE and bleeding were significant for CrCl<60 ml/min OR: 2.54 (95% CI: 1.61-39.7, P = 0.011), age OR: 3.29 (95% CI: 1.07-1.39, P<0.001) and female gender OR: 2.1 (95% CI: 0.036-0.89, P = 0.036). Risk of complications increased with decreasing renal function: 2.7, 14.2, and 37.5% for CrCl of >60, 30-60 or <30 ml/min, respectively, P = 0.002).

CONCLUSION

Advanced age, renal dysfunction, and female gender remain important risk factors for ischemic and bleeding complications in patients undergoing PCI with bivalirudin.