Anaesthesia and Intensive Care

Newer generation drug-eluting stents are the most commonly inserted stent in the setting of percutaneous coronary intervention. This narrative review focuses on the evidence underpinning the perioperative management of patients with newer generation drug-eluting stents undergoing non-cardiac surgery. Six studies reported the incidence of major adverse cardiovascular events according to the time interval from percutaneous coronary intervention to non-cardiac surgery, and the comparative risks of newer and first generation drug-eluting stents. No study demonstrated an increased risk of major adverse cardiovascular events once three months had elapsed between stent implantation and non-cardiac surgery. Only one study included patients with third and fourth generation drug-eluting stents. Seven studies analysed the relationship between antiplatelet therapy, major adverse cardiovascular events and perioperative bleeding. The risks of major adverse cardiovascular events do not appear to be increased if antiplatelet therapy is ceased for less than seven days but are increased if it is discontinued for more than seven days. Most studies reported no differences in the incidence of major bleeding associated with antiplatelet therapy. The risk of perioperative major adverse cardiovascular events in non-cardiac surgery does not appear to be increased after three months following implantation with newer generation drug-eluting stents. However, the possibility of increased risk cannot be excluded as most studies were inadequately powered. The thrombotic risk is substantially reduced in patients with fourth (polymer free) generation drug-eluting stents, and urgent non-cardiac surgery can be considered one month after percutaneous coronary intervention. Larger multicentre studies are needed to define the optimal window for non-cardiac surgery after percutaneous coronary intervention and provide definitive perioperative strategies for patients presenting for non-cardiac surgery after the implantation of newer generation drug-eluting stents.

This paper reviews the natural and treated history of hepatitis C virus infection, the interactions between current therapies and anaesthesia medications, and the implications of occupational exposure and infection to anaesthetists in light of significant changes in treatment. In the past decade, the introduction of new direct acting antiviral medications has seen high cure rates with a sustained viral response across all virus genotypes. These medications are well tolerated with minimal side-effects. Should a patient on these medications require anaesthesia, there are few clinically significant interactions with commonly used anaesthesia medications, and minimal perioperative investigations are required, although delaying elective surgery until after the completion of treatment regimens should be considered to maximise treatment success. As anaesthetists may practise exposure-prone procedures, regular screening for hepatitis C virus infection remains recommended to enable both patient protection and treatment of the anaesthetist prior to the development of any long-term complications of hepatitis C virus infection. Similarly, early diagnosis and treatment of occupationally acquired hepatitis C virus infection after body fluid exposure is associated with high cure rates with minimal risk of long-term liver damage. Although hepatitis C virus infection remains a significant public health issue in Australia and New Zealand, improvements in outcomes as a result of new treatment regimens have allowed the World Health Organization to target the elimination of hepatitis C virus infection as a public health threat by 2030, and public health strategies are being implemented to achieve this goal.

In patients admitted to hospital, preoperative mild cognitive impairment predicts postoperative complications. The effect of mild cognitive impairment on discharge readiness among the day stay surgery population is unknown. Our aims were to determine the incidence of impaired cognitive performance at discharge after day stay endoscopy and whether pre-existing mild cognitive impairment was associated with its development. A single-centre cohort study of elective day stay endoscopy patients was undertaken. Over a three-month period, data were collected from 69 patients aged 65 years and over. Patients were cognitively assessed on admission and discharge using the Montreal cognitive assessment tool and the three-minute diagnostic confusion assessment method. At baseline, patients who scored 1.5 or more standard deviations below age-adjusted levels on the Montreal cognitive assessment tool in conjunction with a subjective memory complaint were classified as having mild cognitive impairment. At discharge, patients were classified as having impaired cognitive performance if there was a reduction in the Montreal cognitive assessment tool score by at least two points. We also assessed delirium and subsyndromal delirium at discharge using the three-minute diagnostic confusion assessment method. We identified mild cognitive impairment in 23 patients (33.3%) on admission, and impaired performance on the Montreal cognitive assessment tool test at discharge in 35 (50.7%) patients. There was no association between mild cognitive impairment on admission and impaired cognitive performance at discharge (50.0% versus 51.1%, P = 0.94). This study demonstrates that evidence of impaired cognitive performance on the Montreal cognitive assessment tool testing is present after day stay endoscopy in over 50% of elderly patients, but this is not associated with preoperative cognitive status.

Persistent tachycardia in patients with septic shock predicts poor outcome. This study sought to investigate the effect of the cardiac pacemaker current inhibitor ivabradine on heart rate and cardio-circulatory function in patients with septic shock. After informed consent, 60 patients with septic shock and persistent tachycardia (heart rate >95 /minute) were prospectively randomly assigned to receive either standard therapy for septic shock (group S) or standard therapy along with enteral ivabradine (group I) for the initial 96 hours after enrolment. Primary outcome was the difference in heart rate between the two groups during the first 96 hours. Secondary outcomes included the effect of ivabradine on haemodynamic, oxygenation, myocardial function and organ function parameters, incidence of adverse events and 30-day overall survival. Heart rate was lower in group I compared to group S (median difference in area under the curve –25.6 (95% confidence intervals –31.4 to –15.9) /minute; P <0.001). Vasopressor requirements, blood lactate levels, Sequential Organ Failure Assessment scores and E/e′ ratio were lower in group I compared to group S. Stroke volume index and ejection fraction were higher in group I while cardiac index and oxygen delivery parameters were maintained similar to group S. There was no difference in 30-day mortality or in the incidence of serious adverse events. Enteral ivabradine is effective in reducing heart rate, and improving haemodynamic parameters and cardiac function in patients with septic shock and persistent tachycardia, without increasing the incidence of adverse events.

There are no published data on the age of retirement of anaesthetists in Australia and New Zealand. We surveyed 622 retired Fellows of the Australian and New Zealand College of Anaesthetists to determine their ages of complete retirement from clinical practice, demographics, and whether they had retired at the age they had intended to retire. We also aimed to explore factors affecting the decision to retire, the practice of ‘winding down’, common post-retirement activities, and the arrangement of personal and professional affairs. Responses were received from 371 specialists (response rate 60%). The mean (standard deviation) age of retirement was 65.2 (6.9) years. The mean (standard deviation) retirement ages ranged from 62.0 (7.1) years (those who retired earlier than planned) to 68.2 (4.3) years (those who retired later than they had intended). The mean (standard deviation) age of retirement of the male respondents was 66.0 (6.5) years, and for female respondents was 62.7 (7.7) years. Two hundred and thirty-three respondents (63%) reported winding down their practice prior to retirement, and 360 (97%) had made a will. Poor health and loss of confidence were the two most common factors in the retirement decisions of those who retired earlier than they had planned. Our results may assist current practitioners plan for retirement, and suggest strategies to help health services, departments and private groups accommodate individuals in winding down their practice.