Perioperative stroke

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.

Intraoperative hypotension in noncardiac surgery patients with chronic beta-blocker therapy: A matched cohort analysis

STUDY OBJECTIVE

To explore the incidence of intraoperative hypotension in patients with chronic beta-blocker therapy, expressed as time spent, area and time-weighted average under predefined mean arterial pressure thresholds.

DESIGN

Retrospective analysis of a prospective observational cohort registry.

SETTING

Patients ≥60 years undergoing intermediate- to high-risk noncardiac surgery with routine postoperative troponin measurements on the first three days after surgery.

PATIENTS

1468 matched sets of patients (1:1 ratio with replacement) with and without chronic beta-blocker treatment.

INTERVENTIONS

None.

MEASUREMENTS

The primary outcome was the exposure to intraoperative hypotension in beta-blocker users vs. non-users. Time spent, area and time-weighted average under predefined mean arterial pressure thresholds (55-75 mmHg) were calculated to express the duration and severity of exposure. Secondary outcomes included incidence of postoperative myocardial injury and thirty-day mortality, myocardial infarction (MI) and stroke. Furthermore, analyses for patient subgroup and beta-blocker subtype were conducted.

MAIN RESULTS

In patients with chronic beta-blocker therapy, no increased exposure to intraoperative hypotension was observed for all characteristics and thresholds calculated (all P > .05). Beta-blocker users had lower heart rate before, during and after surgery (70 vs. 74, 61 vs. 65 and 68 vs. 74 bpm, all P < .001, respectively). Postoperative myocardial injury (13.6% vs. 11.6%, P = .269) and thirty-day mortality (2.5% vs. 1.4%, P = .055), MI (1.4% vs. 1.5%, P = .944) and stroke (1.0% vs 0.7%, P =  .474) rates were comparable. The results were consistent in subtype and subgroup analyses.

CONCLUSIONS

In this matched cohort analysis, chronic beta-blocker therapy was not associated with increased exposure to intraoperative hypotension in patients undergoing intermediate- to high-risk noncardiac surgery. Furthermore, differences in patient subgroups and postoperative adverse cardiovascular events as a function of treatment regimen could not be demonstrated.

Management of Postoperative Myocardial Injury After Non-cardiac Surgery in Patients Aged ≥ 80 Years: Our 10 Years' Experience

Background

Postoperative myocardial injury (PMI) is associated with short- and long-term mortality. The incidence of PMI in very old patients is currently unknown. There is currently neither known effective prophylaxis nor a uniform strategy for the elderly with PMI.

Objective

To share our 10 years of experience in the comprehensive management of PMI after non-cardiac surgery in patients aged ≥ 80 years.

Methods

In this case series, we retrospectively collected and assessed the 2,984 cases aged ≥ 80 years who accepted non-cardiac surgery from 2011 to 2021 at the second Medical Center, Chinese PLA General Hospital. The incidence, risk factors, management strategy, and prognosis of surgical patients with PMI were analyzed.

Results

A total of 2,984 patients met our inclusion criteria. The overall incidence of PMI was 14%. In multivariable analysis, coronary artery disease, chronic heart failure, and hypotension were independently associated with the development of PMI. The patients with PMI were at a higher risk of death (OR, 2.69; 95% CI, 1.78–3.65). They were more likely to have received low molecular heparin, anti-plantlet therapy, beta-blocker, early coronary angiography, and statin than patients without PMI. The 30-day (0.96% vs. 0.35%; OR 3.46; 95% CI, 1.49–7.98; P &lt; 0.001) and 1-year mortality (5.37% vs. 2.60%; OR 2.35; 95% CI, 1.12–6.53; P &lt; 0.001) was significantly higher in patients with PMI compared with those without PMI.

Conclusions

The incidence of PMI in very old patients was high. The PMI is associated with an increased risk of 30 days and 1-year mortality. These patients can benefit from intensification of assessment and individualized care of multi-morbidities during the perioperative period. Especially cardiovascular medical treatments, such as antiplatelet, anticoagulation, β-blockers, and statins are very important for patients with PMI.

Perioperative Care of Patients at High Risk for Stroke During or After Non-cardiac, Non-neurological Surgery: 2020 Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care

Perioperative stroke is associated with considerable morbidity and mortality. Stroke recognition and diagnosis are challenging perioperatively, and surgical patients receive therapeutic interventions less frequently compared with stroke patients in the outpatient setting. These updated guidelines from the Society for Neuroscience in Anesthesiology and Critical Care provide evidence-based recommendations regarding perioperative care of patients at high risk for stroke. Recommended areas for future investigation are also proposed.

Risk of cardiovascular complications during non-cardiac surgery and preoperative cardiac evaluation

The preoperative evaluation of candidates to non-cardiac surgery requires a knowledge of factors related both to the type of surgery and to the risk of each patient, in order to predict the potential cardiovascular complications. Over the past several decades, the field of preoperative cardiac evaluation before non-cardiac surgery has evolved substantially on the basis of the current guidelines of international medical societies. The aim of this paper is to summarize available evidence on the risk of non-cardiac surgery, focusing on appropriate cardiovascular assessment prior to surgery.

Mitigating the stress response to improve outcomes for older patients undergoing emergency surgery with the addition of beta-adrenergic blockade

As population age, healthcare systems and providers are likely to experience a substantial increase in the proportion of elderly patients requiring emergency surgery. Emergency surgery, compared with planned surgery, is strongly associated with increased risks of adverse postoperative outcomes due to the short time available for diagnosis, optimization, and intervention in patients presenting with physiological derangement. These patient populations, who are often frail and burdened with a variety of co-morbidities, have lower reserves to deal with the stress of the acute condition and the required emergency surgical intervention. In this review article, we discuss topical areas where mitigation of the physiological stress posed by the acute condition and asociated surgical intervention may be feasible. We consider the impact of the adrenergic response and use of beta blockers for these high-risk patients and discuss common risk factors such as frailty and delirium. A proactive multidisciplinary approach to peri-operative care aimed at mitigation of the stress response and proactive management of common conditions in the older emergency surgical patient could yield more favorable outcomes.

Perioperative Neurological Evaluation and Management to Lower the Risk of Acute Stroke in Patients Undergoing Noncardiac, Nonneurological Surgery: A Scientific Statement From the American Heart Association/American Stroke Association

Perioperative stroke is a potentially devastating complication in patients undergoing noncardiac, nonneurological surgery. This scientific statement summarizes established risk factors for perioperative stroke, preoperative and intraoperative strategies to mitigate the risk of stroke, suggestions for postoperative assessments, and treatment approaches for minimizing permanent neurological dysfunction in patients who experience a perioperative stroke. The first section focuses on preoperative optimization, including the role of preoperative carotid revascularization in patients with high-grade carotid stenosis and delaying surgery in patients with recent strokes. The second section reviews intraoperative strategies to reduce the risk of stroke, focusing on blood pressure control, perioperative goal-directed therapy, blood transfusion, and anesthetic technique. Finally, this statement presents strategies for the evaluation and treatment of patients with suspected postoperative strokes and, in particular, highlights the value of rapid recognition of strokes and the early use of intravenous thrombolysis and mechanical embolectomy in appropriate patients.

Perioperative pharmacotherapy to prevent cardiac complications in patients undergoing noncardiac surgery

Introduction: Despite advances in surgical and anesthetic techniques, perioperative cardiovascular complications are a major cause of 30-day perioperative mortality. Major cardiovascular complications after noncardiac surgery include myocardial ischemia, congestive heart failure, arrhythmias, and cardiac arrest. Along with surgical risk assessment, perioperative medical optimization can reduce the rates and clinical impact of these complications.Areas Covered: In this review, the authors discuss the pharmacological basis, existing evidence, and professional society recommendations for drug management in preventing cardiovascular complications in patients undergoing noncardiac surgery.Expert opinion: Perioperative management of cardiovascular disease is an increasingly important and growing area of clinical practice. Societal guidelines regarding the use of most routine cardiovascular medications are based on a number of large clinical studies and provide a basic foundation to guide management. However, the heterogeneous nature of patients, as well as surgeries, makes it practically impossible to devise a 'one size fits all' recommendation in this setting. Thus, the importance of a more individualized approach to perioperative risk stratification and management is being increasingly recognized. The underlying comorbidities and cardiac profile as well as the risk of cardiac complications associated with the planned surgery must be factored in to understand the nuance of the management strategies.

Contemporary personalized β-blocker management in the perioperative setting

Beta-adrenergic blockers (β-blockers) are clearly indicated for the long-term treatment of patients with systolic heart failure and post-acute myocardial infarction. Early small-scale studies reported their potential benefits for perioperative use; subsequent randomized controlled trials, however, failed to reproduce earlier findings. Furthermore, their role in reducing major postoperative cardiac events following noncardiac and cardiac surgery remains controversial. This case-based review presents an overview of contemporary literature on perioperative β-blocker use with a focus on data available since 2008 when the PreOperative ISchemic Evaluation (POISE) trial was published. Our review suggests that studies should determine the effects of situational-based guidelines on perioperative β-blocker use on the risk of cardiac adverse events and mortality in the perioperative period.

Preoperative chronic beta-blocker prescription in elderly patients as a risk factor for postoperative mortality stratified by preoperative blood pressure: a cohort study

BACKGROUND

Recent data suggest that beta blockers are associated with increased perioperative risk in hypertensive patients. We investigated whether beta blockers were associated with an increased risk in elderly patients with raised preoperative arterial blood pressure.

METHODS

We conducted a propensity-score-matched cohort study of primary care data from the UK Clinical Practice Research Datalink (2004-13), including 84 633 patients aged 65 yr or over. Conditional logistic regression models, including factors that were significantly associated with the outcome, were constructed for 30-day mortality after elective noncardiac surgery. The effects of beta blockers (primary outcome), renin-angiotensin system (RAS) inhibitors, calcium-channel blockers, thiazides, loop diuretics, and statins were investigated at systolic and diastolic arterial pressure thresholds.

RESULTS

Beta blockers were associated with increased odds of postoperative 30-day mortality in patients with systolic hypertension (defined as systolic BP >140 mm Hg; adjusted odds ratio [aOR]: 1.92; 95% confidence interval [CI]: 1.05-3.51). After excluding patients for whom prior data suggest benefit from perioperative beta blockade (patients with prior myocardial infarction or heart failure), rather than adjusting for them, the point estimate shifted slightly (aOR: 2.06; 95% CI: 1.09-3.89). Compared with no use, statins (aOR: 0.35; 95% CI: 0.17-0.75) and thiazides (aOR: 0.28; 95% CI: 0.10-0.78) were associated with lower mortality in patients with systolic hypertension.

CONCLUSIONS

These data suggest that the safety of perioperative beta blockers may be influenced by preoperative blood pressure thresholds. A randomised controlled trial of beta-blocker withdrawal, in select populations, is required to identify a causal relationship.

What we can learn from Big Data about factors influencing perioperative outcome

PURPOSE OF REVIEW

This narrative review will discuss what value Big Data has to offer anesthesiology and aims to highlight recently published articles of large databases exploring factors influencing perioperative outcome. Additionally, the future perspectives of Big Data and its major pitfalls will be discussed.

RECENT FINDINGS

The potential of Big Data has given an incentive to create nationwide and anesthesia-initiated registries like the MPOG and NACOR. These large databases have contributed in elucidating some of the rare perioperative complications, such as declined cognition after exposure to general anesthesia and epidural hematomas in parturients. Additionally, they are useful in finding patterns such as similar outcome in subtypes of beta-blockers and lower incidence of pneumonia in preoperative influenza vaccinations in the elderly.

SUMMARY

Big Data is becoming increasingly popular with the collaborative collection of registries offering anesthesia a way to explore rare perioperative complications and outcome to encourage further hypotheses testing. Although Big Data has its flaws in security, lack of expertise and methodological concerns, the future potential of analytics combined with genomics, machine learning and real-time decision support looks promising.

Seasonal occurrence and fate of chiral pharmaceuticals in different sewage treatment systems in Hong Kong: Mass balance, enantiomeric profiling, and risk assessment

Concern about the presence of chiral pharmaceuticals in the environment from wastewater discharge is mounting. In this work, the occurrence and fate of atenolol, metoprolol, venlafaxine, and chloramphenicol, including 10 different stereoisomers, were investigated in sewage and sludge from diverse treatment processes in 4 sewage treatment plants (STPs) in Hong Kong via 4 sampling campaigns over a period of 2 years. The average amounts of individual pharmaceuticals entering the STPs ranged from 4.91 g/d to 6290 g/d, with sludge carrying much lower amounts than the discharged effluent. Mass balance analysis revealed that: larger quantities of these pharmaceuticals were released during the dry seasons, biodegradation was the primary removal mechanism for atenolol and chloramphenicol, and the removal via primary sedimentation and disinfection processes was insignificant (<30%). Selectivity toward R-(+)-atenolol, S-(-)-metoprolol, and R-(-)-venlafaxine was mostly found across secondary-treated effluent samples. Sold as an enantiopure pharmaceutical in R,R-para-form, chloramphenicol was preferentially eliminated after biological process. This is the first study on the occurrence of chloramphenicol enantiomers in the aquatic environment. Ecotoxicological assessment indicated that atenolol and metoprolol could pose risks to marine fish in effluent-receiving waters (i.e., the western waters and Victoria Harbor) of Hong Kong, while R-(+)-atenolol could pose a risk to protozoans five times higher than the S-(-)-enantiomer.

Beta-blockers in noncardiac surgery: Did observational studies put us back on safe ground?

Based on landmark trials, international guidelines had for years promoted the use of beta-blockers in the setting of non-cardiac surgery. In 2011, concerns were raised regarding the integrity of some of the landmark trials, as the Dutch Erasmus Medical Center found some of them to be scientifically incorrect. Based on the remaining studies that were to be trusted, investigations showed that, in contrast to prior beliefs, the widespread use of perioperative beta-blockers might be harmful. A call for further investigations into the matter ushered in several observational studies evaluating the safety of perioperative beta-blocker therapy in specific patient subgroups. Within this review, we discuss important aspects for making these decisions, and compare the major observational studies and specific estimates of risk in subgroups of interest. We conclude that patients at high risk with heavy co-morbidities, such as heart failure, may benefit from beta-blocker therapy, whereas low-risk patients, such as patients with uncomplicated hypertension, may be at increased risk with beta-blocker therapy. We provide a critical review of current perioperative guidelines in view of the new observational data, suggesting that the recommended schematics, such as the Revised Cardiac Risk Index, for risk stratification of patients in this setting may be suboptimal. Further, we provide discussions of other aspects, including risk of sepsis, type of beta-blocker, and the potential of perioperative beta-blocker withdrawal, which may be important in guiding future studies. Summarising the current evidence, we argue that, after a precarious decade, we may just now, be back on safe ground.