Assessing and reducing cardiac risks of noncardiac surgery

Cardiac output monitoring using indicator-dilution techniques: basics, limits, and perspectives

The ability to monitor cardiac output is one of the important cornerstones of hemodynamic assessment for managing critically ill patients at increased risk for developing cardiac complications, and in particular in patients with preexisting cardiovascular comorbidities. For >30 years, single-bolus thermodilution measurement through a pulmonary artery catheter for assessment of cardiac output has been widely accepted as the "clinical standard" for advanced hemodynamic monitoring. In this article, we review this clinical standard, along with current alternatives also based on the indicator-dilution technique, such as the transcardiopulmonary thermodilution and lithium dilution techniques. In this review, not only the underlying technical principles and the unique features but also the limitations of each application of indicator dilution are outlined.

Risk assessment in coronary patients undergoing abdominal nonvascular surgery

The aim of our study was to establish that the incidence of perioperative cardiac complications were in direct correlation with level of operative risk in coronary patients undergoing open abdominal nonvascular surgery with general anesthesia. Our prospective observational clinical study was composed of a group of 111 consecutive patients with angiographically-verified coronary artery disease, who were operated on at the University Clinical Center of Serbia. The patients were classified into four stratification subgroups by “Goldman’s Cardiac Risk Index” (CRI) in relation to the incidence of perioperative cardiac complications. Electrocardiography was performed immediately after surgery, on postoperative days 1, 2, 7 and one day before discharge from the hospital. All patients were followed to postoperative day 30. Statistical design was presented by Pearson’s χ2 test and binomial logistic regression. The main result was significant difference between the four stratification subgroups of coronary patients in the incidence of cardiac death up to the 30th postoperative day: I — 0/17 (0.0%) vs. II — 0/40 (0.0%) vs. III — 1/37 (2.7%) vs. IV — 2/17 (11.8%), (p<0.05). We concluded that the incidence of perioperative cardiac complications significantly increased with the degree of Goldman’s CRI. There was significant difference in the incidence of perioperative cardiac complications between the four Goldman’s stratification subgroups.

Perioperative beta-blockers in high-risk patients

One major risk to patients in the preoperative period is that of myocardial ischemia or infarction and cardiovascular death in high-risk patients. Historically, attempts to decrease the incidence of perioperative cardiac complications have focused on preoperative evaluation and identification of patients at risk for complications with referral for additional testing and/or revascularization. Evidence suggests that the use of perioperative beta-blockers in high-risk individuals can reduce the incidence of perioperative cardiac events. The Agency for Healthcare Research and Quality has identified that the use of perioperative beta-blockers can reduce perioperative morbidity and mortality. The focus of this article is to describe the evidence supporting perioperative beta-blocker use, to discuss potential barriers to their use, and to propose a strategy to improve their use.

Anaesthesia and endovascular surgery

Anaesthetic requirements for endovascular surgery for aortic, carotid and peripheral vascular disease are reviewed. Peculiarities of the surgery which may impinge on anaesthetic management are discussed together with the pre-operative assessment issues of particular relevance to patients with generalized vascular disease. The detailed anaesthetic management for carotid and aortic endovascular repair is addressed. The lowered peri-operative stress and general morbidity levels which occur with endovascular surgery allow sicker patients with greater risk factors to present for this type of surgery, thus increasing the challenges facing anaesthetists.