Preoperative cardiac risk management

Numerous strategies exist for preoperative cardiac testing before patients undergo vascular operations. Potential adverse effects of evaluation and cardiac intervention should be considered before undertaking screening studies. We recently analyzed the adverse outcomes of preoperative cardiac evaluation and intervention before vascular operations in patients treated at the Denver Department of Veterans Affairs Medical Center. During the 12 month study period, 161 patients were scheduled to undergo major vascular operations; 153 patients came to operation. The decision to pursue a cardiac evaluation was made without a defined protocol. Forty two men, aged 68+/-9 years underwent comprehensive preoperative cardiac evaluations Sixteen (38%) patients had untoward events related to cardiac evaluation, including eight patients (19%) who refused vascular surgery after cardiac screening and/or intervention. Other complications included prosthetic graft infection, pseudoaneurysms (2), sternal wound infections (2) amputations (2), renal failure and brain anoxia. Extensive cardiac evaluation prior to vascular operations can result in morbidity, delays, and refusal to undergo vascular surgery. The underlying indication for vascular operations and the local iatrogenic cardiac complication rates must be considered before ordering special studies.     

Preoperative identification of cardiac risk patients and perioperative management

The demographic trend challenges anaesthesiologists with a growing number of elderly requiring surgery. The anaesthetist needs to identify risk patients and to optimize his strategies for perioperative management. The present article gathers the current data and summarizes effective strategies for anaesthesia in patients with ischemic heart disease.     

Preoperative assessment of cardiac risk and perioperative cardiac management in noncardiac surgery

More than 27 million Americans undergo noncardiac surgery annually. Cardiac complications can be a major source of morbidity and mortality in the perioperative period. Preoperative risk stratification, intraoperative ischemia monitoring and postoperative surveillance help to predict, identify and efficiently treat these adverse events. A renewed emphasis on preoperative evaluation has helped to identify patients at an increased risk for adverse cardiac events and thus, implement noninvasive or invasive cardio protective strategies in an attempt to minimize these complications. In this review we briefly describe the current evidence on perioperative management of patients presenting for noncardiac surgery. As the surgeon will remain one of the first to evaluate patients before noncardiac surgery it is essential he/she be well versed with this information.     

Preoperative cardiac risk assessment prior to noncardiac surgery

Summary. Cardiac complications remain an important cause of perioperative morbidity and mortality with noncardiac surgery, despite improvement in surgical techniques and anaesthetic management. Therefore preoperative cardiovascular risk assessment plays a pivotal role in management of patients prior to noncardiac surgery. Thorough history-taking and careful examination are essential to consider further diagnostic steps in order to predict the patient's individual perioperative cardiac risk as accurately as possible. Besides elaboration of medical therapy, cardiac catherization and even balloon angioplasty or bypass surgery must be considered if indicated by preoperative cardiac testing.      

Preoperative cardiac risk assessment: an updated approach.

HYPOTHESIS: We provide an updated algorithm for approaching preoperative cardiac risk assessment in patients undergoing noncardiac surgery. DESIGN: A National Library of Medicine PubMed literature search was performed dating back to 1985 using the keywords "preoperative cardiac risk for noncardiac surgery." This search was restricted to English language articles involving human subjects. RESULTS: Patient-specific and operation-specific cardiac risk can be determined clinically. Patients with major cardiac risk factors have a high incidence of perioperative cardiac complications, whereas the risk is less than 3% for low-risk patients. For intermediate-risk patients, no prospective randomized studies demonstrate the efficacy of noninvasive stress testing (dipyridamole thallium or dobutamine echocardiography) or of subsequent coronary revascularization for preventing perioperative cardiac complications. Recent studies demonstrate that perioperative beta-blockade significantly reduces the adverse cardiac event rate in intermediate-risk patients. CONCLUSIONS: Most patients with high cardiac risk should proceed with coronary angiography. Patients with low cardiac risk can proceed to surgery without noninvasive testing. For intermediate-risk patients, consideration may be given to further stress testing prior to surgery; however, in most patients, proceeding to surgery with perioperative beta-blockade is an acceptable alternative.     

Preoperative risk prediction and intraoperative events in cardiac surgery.

OBJECTIVE: To examine the relationship between preoperative risk prediction and intraoperative events. METHODS: A total of 3118 patients operated in 1999 and 2000 at our institution were analysed, all of whom had their EuroSCORE collected prospectively. The intraoperative variables studied were consultant or trainee operating, long bypass time, long ischaemic time, return on bypass in theatre and use of intra-aortic balloon pump at the end of the procedure. The outcomes are reported as hospital mortality, prolonged length of stay in the intensive therapy unit (pLOS-ITU, >48 h) and death or pLOS-ITU. Risk models were constructed by logistic regression for predicting these three outcomes. RESULTS: With the exception of prolonged cross-clamp time, all variables analysed were independently predictive of a negative outcome. Trainee operating had an apparent protective effect. All risk models performed well. The area under the receiver operating characteristic (ROC) curve (95% CI) increased from 0.857 (0.81, 0.90) for EuroSCORE to 0.874 (0.83, 0.92) for the risk of death model. Similarly, the area under the ROC curve for the pLOS-ITU model increased from 0.687 (0.642, 0.732) to 0.734 (0.691, 0.777) and for the death or pLOS-ITU model from 0.717 (0.677, 0.756) to 0.757 (0.719, 0.795). CONCLUSIONS: Knowledge of adverse intraoperative events enhances preoperative risk prediction. This type of analysis could be used for identifying "near miss" outcomes in adult cardiac surgery.     

Preoperative anxiety in children risk factors and non-pharmacological management

It is important for anesthesiologists to appreciate the impact of preoperative anxiety in children. Not only does it cause suffering in many children prior to their surgical experience, it has a negative impact on their postoperative recovery and possibly long afterwards. Because of these concerns, continued research is warranted to seek ways of minimizing their fears in the perioperative setting. In this review, we will examine the risk factors for preoperative anxiety, tools for quantifying children and parent's anxiety, and strategies that may play a part in decreasing preoperative anxiety. Variables, which influence preoperative anxiety in children, include their age, temperament, prior hospital experience and parent coping abilities. This review will also explore issues surrounding parental presence during a child's anesthesia induction and how understanding child development can enhance their cooperativeness during the preoperative period, especially during anesthesia induction. Non-pharmacological interventions as a means of decreasing pediatric anxiety will be explored. Finally recent trends and new directions will be touched upon.     

Preoperative evaluation of cardiac risk using dobutamine-thallium imaging in vascular surgery

Coronary artery disease is frequently present in patients undergoing evaluation for reconstructive peripheral vascular surgery. Dobutamine-thallium imaging has been shown to be a reliable and sensitive noninvasive method for the detection of significant coronary artery disease. Eighty-seven candidates for vascular reconstruction underwent dobutamine-thallium imaging. Forty-eight patients had an abnormal dobutamine-thallium scan. Twenty-two patients had infarct only, while 26 had reversible ischemia demonstrated on dobutamine-thallium imaging. Fourteen of 26 patients with reversible ischemia underwent cardiac catheterization and 11 showed significant coronary artery disease. Seven patients underwent preoperative coronary artery bypass grafting or angioplasty. There were no postoperative myocardial events in this group. Three patients were denied surgery on the basis of unreconstructible coronary artery disease, and one patient refused further intervention. Ten patients with reversible myocardial ischemia on dobutamine-thallium imaging underwent vascular surgical reconstruction without coronary revascularization and suffered a 40% incidence of postoperative myocardial ischemic events. Five patients were denied surgery because of presumed significant coronary artery disease on the basis of the dobutamine-thallium imaging and clinical evaluation alone. Thirty-nine patients with normal dobutamine-thallium scans underwent vascular reconstructive surgery with a 5% incidence of postoperative myocardial ischemia. Dobutamine-thallium imaging is a sensitive and reliable screening method which identifies those patients with coronary artery disease who are at high risk for perioperative myocardial ischemia following peripheral vascular surgery. Presented at the Annual Meeting of the Peripheral Vascular Surgery Society, New York, New York, June 17, 1989.     

Preoperative cardiac optimization

Perioperative cardiovascular complications are associated with significant morbidity and mortality. Thorough preoperative assessment and subsequent targeted optimization can improve patient outcome. This article summarizes currently available international guidelines and provides suggestions for appropriate management of commonly encountered cardiac conditions, including hypertension, coronary artery disease, heart failure and valve diseases.     

Preoperative cardiac evaluation

The current standards for preoperative cardiac evaluation and the guidelines published by the American College of Cardiology and the American Heart Association call for noninvasive or invasive cardiac evaluation in certain patients. Perioperative use of beta-adrenergic blockade has been shown to reduce cardiac complication rates, diminishing the positive predictive value and the likelihood ratio of a positive result of a preoperative cardiac test,unfavorably shifting the risk to benefit ratio of preoperative tests and any possible therapeutic action that one might take based on the test. A new paradigm might be emerging that makes cardiac tests unnecessary except in the highest-risk patients identified by clinical variables.     

Preoperative cardiac evaluation

Guidelines on perioperative cardiovascular evaluation for noncardiac surgery have been published. The integration of clinical risk factors, surgery-specific risk,and functional capacity should be used to determine the need for further diagnostic evaluation. The use of beta-adrenergic blockade in high-risk patients,particularly those with documented myocardium at risk undergoing vascular surgery, has been shown to reduce perioperative risk and may obviate the need for more invasive procedures. Coronary intervention should be reserved for those patients who warrant intervention independent of the noncardiac surgery.     

Preoperative cardiac evaluation: mechanisms, assessment, and reduction of risk

The changing paradigm in cardiovascular disease in which atherosclerotic lesions exist in a spectrum of stable to unstable, the lack of a perfect prediction tool, and the paucity of randomized controlled data on appropriate intervention make protection of cardiac patients undergoing thoracic surgery challenging. Nociception-related sympathetic drive combines with inflammatory stimuli and the cardiodepressant effects of anesthesia to create a window of maximum risk in the early postoperative period (8-24 hours), and although multivariate models have shown that a combination of surgery-specific risk, patient-specific cardiovascular history, and estimated functional capacity best determine the need for further investigation, the optimal choice of investigation is unclear. Exercise or dobutamine stress echocardiography provide the best validated investigations, and in the case of poor images, dobutamine MR imaging is increasingly used. When disease is found, medical and interventional options are available. PCI is often used, but the risk of converting a stable flow-limiting lesion into a less stable non-flow-limiting lesion must be considered, along with a delay for anti-platelet therapy and endothelialization of the stent. Alternatively, medical protection with acute beta-blockade or alpha2-agonists reduces risk (although beta-blockade often is avoided in chronic lung disease, even nonselective agents are safe in patients with non-airways reactive COPD). In addition, it is likely that statin use reduces risk, probably by stabilizing plaques, but patients with cardiac risk are increasingly likely to be taking this medication already. The assessment and management of cardiac risk in the perioperative thoracic surgery patient is challenging. With focused, rational, and individually tailored management; tight monitoring of postoperative pain; and a close working relationship between the surgeon, anesthesiologist, and cardiologist, patient care can be optimized, and risk can be effectively controlled.     

Preoperative risk assessment in cardiac surgery: comparison of predicted and observed results

In the present climate of quality-assurance policies, rigorous requirements for informed consent, and a constantly changing patient population, a system of preoperative risk assignment and postoperative correlation was developed to monitor and evaluate surgical performance. Patients were categorized by operation, priority (emergent, urgent, elective), New York Heart Association Functional Class, and risk. Risk was assigned before operation using data from the Coronary Artery Surgery Study (CASS) and the recent literature. Data were collected by a full-time data manager and were stored and analyzed by computer. From January 1, 1984, to July 1, 1985, 1,303 patients underwent operation for acquired disease. This group included 913 patients undergoing isolated primary coronary artery bypass grafting (CABG). The comparison of predicted and observed results showed: (Table: see text). For patients undergoing isolated primary CABG, the elective group had an operative mortality of 0.6% (2/329); the urgent group, 1.1% (5/450); and the emergent group, 5.2% (7/134). Preoperative risk assignment is an effective method of quality assurance. Female sex and age older than 60 years, which predicted an operative mortality of 2 to 5% in the CASS study and other recent series, did not predict a similar risk in our series.     

Preoperative assessment for cardiac surgery

Anaesthetic challenges in cardiac surgery are multifaceted. Since patients present with compromised cardiovascular reserve and multiple co-morbidities, a thorough preoperative assessment and meticulous anaesthetic plan is essential. This targets anaesthetic history, physical examination and analysis of investigations, routine and specific to the cardiovascular system. Special models exist for risk stratification to aid perioperative planning, surgical decision making, benchmarking and quality assurance. This article provides an overview of history, examination and preoperative management of patients undergoing cardiac surgery. Scoring systems and practical investigations are reviewed.     

Preoperative assessment for cardiac surgery

Anaesthetic challenges in cardiac surgery are multifaceted. Since patients present with compromised cardiovascular reserve and multiple comorbidities, a thorough preoperative assessment and meticulous anaesthetic plan is essential. This targets anaesthetic history, physical examination and analysis of investigations, routine and specific to the cardiovascular system. Special models exist for risk stratification to aid perioperative planning, surgical decision making, benchmarking and quality assurance. This article provides an overview of history, examination and preoperative management of patients undergoing cardiac surgery. Scoring systems and practical investigations are reviewed.     

Preoperative assessment for cardiac surgery

Patients presenting for cardiac surgery pose several challenges for the anaesthetist. Not only are they preparing for major surgery to improve impaired cardiovascular function, but many also suffer from significant co-morbid disease. Thorough preoperative assessment and investigation is imperative. This allows identification of those patients at high risk of perioperative complications, and promotes development of individualized care plans to minimize these risks. The assessment should combine a focused anaesthetic history and examination with the analysis of all cardiovascular investigations, ranging from simple blood tests to complex investigations of cardiac anatomy and function. Scoring systems are often employed as a means of risk stratification and can be used not only to aid in perioperative planning and informed consent, but also as an audit tool.