The Association between Preoperative Blood Pressures and Postoperative Adverse Events

BACKGROUND

The relationship between postoperative adverse events and blood pressures in the preoperative period remains poorly understood. This study tested the hypothesis that day-of-surgery preoperative blood pressures are associated with postoperative adverse events.

METHODS

We conducted a retrospective, observational study of adult patients having elective procedures requiring an inpatient stay between November 2017 and July 2021 at Vanderbilt University Medical Center to examine the independent associations between preoperative systolic and diastolic blood pressures (SBP, DBP) recorded immediately before anesthesia care and number of postoperative adverse events - myocardial injury, stroke, acute kidney injury (AKI), and mortality, while adjusting for potential confounders. We used multivariable ordinal logistic regression to model the relationship.

RESULTS

The analysis included 57,389 cases. The overall incidence of myocardial injury, stroke, AKI, and mortality within 30 days of surgery was 3.4% (1,967 events), 0.4% (223), 10.2% (5,871), and 2.1% (1,223), respectively. The independent associations between both SBP and DBP measurements and number of postoperative adverse events were found to be U-shaped, with greater risk both above and below SBP 143 mmHg and DBP 86 mmHg - the troughs of the curves. The associations were strongest at SBP 173 mmHg (adjusted odds ratio [aOR] 1.212 versus 143 mmHg; 95% CI, 1.021 to 1.439; p = 0.028), SBP 93 mmHg (aOR 1.339 versus 143 mmHg; 95% CI, 1.211 to 1.479; p < 0.001), DBP 106 mmHg (aOR 1.294 versus 86 mmHg; 95% CI, 1.003 to 1.17671; p = 0.048), and DBP 46 mmHg (aOR 1.399 versus 86 mmHg; 95% CI, 1.244 to 1.558; p < 0.001).

CONCLUSIONS

Preoperative blood pressures both below and above a specific threshold were independently associated with a higher number of postoperative adverse events, but the data do not support specific strategies for managing patients with low or high blood pressure on the day of surgery.

Thinking Clearly: The History of Brain Dysfunction in Critical Illness

Brain dysfunction during critical illness (ie, delirium and coma) is extremely common, and its lasting effect has only become increasingly understood in the last two decades. Brain dysfunction in the intensive care unit (ICU) is an independent predictor of both increased mortality and long-term impairments in cognition among survivors. As critical care medicine has grown, important insights regarding brain dysfunction in the ICU have shaped our practice including the importance of light sedation and the avoidance of deliriogenic drugs such as benzodiazepines. Best practices are now strategically incorporated in targeted bundles of care like the ICU Liberation Campaign's ABCDEF Bundle.

Perioperative Neurocognitive Disorders in Adults Requiring Cardiac Surgery: Screening, Prevention, and Management

Neurocognitive changes are the most common complication after cardiac surgery, ranging from acute postoperative delirium to prolonged postoperative neurocognitive disorder. Changes in cognition are distressing to patients and families and associated with worse outcomes overall. This review outlines definitions and diagnostic criteria, risk factors for, and mechanisms of Perioperative Neurocognitive Disorders and offers strategies for preoperative screening and perioperative prevention and management of neurocognitive complications.

Delirium Prevention and Management in Frail Surgical Patients

Delirium, an acute, fluctuating impairment in cognition and awareness, is one of the most common causes of postoperative brain dysfunction. It is associated with increased hospital length of stay, health care costs, and mortality. There is no FDA-approved treatment of delirium, and management relies on symptomatic control. Several preventative techniques have been proposed, including the choice of anesthetic agent, preoperative testing, and intraoperative monitoring. Frailty, a state of increased vulnerability to adverse events, is an independent and potentially modifiable risk factor for the development of delirium. Diligent preoperative screening techniques and implementation of prevention strategies could help improve outcomes in high-risk patients.

Elderly Patients and Management in Intensive Care Units (ICU): Clinical Challenges

There is a growing population of older adults requiring admission to the intensive care unit (ICU). This population outpaces the ability of clinicians with geriatric training to assist in their management. Specific training and education for intensivists in the care of older patients is valuable to help understand and inform clinical care, as physiologic changes of aging affect each organ system. This review highlights some of these aging processes and discusses clinical implications in the vulnerable older population. Other considerations when caring for these older patients in the ICU include functional outcomes and morbidity, as opposed to merely a focus on mortality. An overall holistic approach incorporating physiology of aging, applying current evidence, and including the patient and their family in care should be used when caring for older adults in the ICU.

Association of Time to Surgery After COVID-19 Infection With Risk of Postoperative Cardiovascular Morbidity

IMPORTANCE

The time interval between COVID-19 infection and surgery is a potentially modifiable but understudied risk factor for postoperative complications.

OBJECTIVE

To examine the association between time to surgery after COVID-19 diagnosis and the risk of a composite of major postoperative cardiovascular morbidity events within 30 days of surgery.

DESIGN, SETTING, AND PARTICIPANTS

This single-center, retrospective cohort study was conducted among 3997 adult patients (aged ≥18 years) with a previous diagnosis of COVID-19, as documented by a positive polymerase chain reaction test result, who were undergoing surgery from January 1, 2020, to December 6, 2021. Data were obtained through Structured Query Language access of an existing perioperative data warehouse. Statistical analysis was performed March 29, 2022.

EXPOSURE

The time interval between COVID-19 diagnosis and surgery.

MAIN OUTCOMES AND MEASURES

The primary outcome was the composite occurrence of major cardiovascular comorbidity, defined as deep vein thrombosis, pulmonary embolism, cerebrovascular accident, myocardial injury, acute kidney injury, and death within 30 days after surgery, using multivariable logistic regression.

RESULTS

A total of 3997 patients (2223 [55.6%]; median age, 51.3 years [IQR, 35.1-64.4 years]; 667 [16.7%] African American or Black; 2990 [74.8%] White; and 340 [8.5%] other race) were included in the study. The median time from COVID-19 diagnosis to surgery was 98 days (IQR, 30-225 days). Major postoperative adverse cardiovascular events were identified in 485 patients (12.1%). Increased time from COVID-19 diagnosis to surgery was associated with a decreased rate of the composite outcome (adjusted odds ratio, 0.99 [per 10 days]; 95% CI, 0.98-1.00; P = .006). This trend persisted for the 1552 patients who had received at least 1 dose of COVID-19 vaccine (adjusted odds ratio, 0.98 [per 10 days]; 95% CI, 0.97-1.00; P = .04).

CONCLUSIONS AND RELEVANCE

This study suggests that increased time from COVID-19 diagnosis to surgery was associated with a decreased odds of experiencing major postoperative cardiovascular morbidity. This information should be used to better inform risk-benefit discussions concerning optimal surgical timing and perioperative outcomes for patients with a history of COVID-19 infection.

Motoric Subtypes of Delirium and Long-Term Functional and Mental Health Outcomes in Adults After Critical Illness

OBJECTIVES

Adult ICU survivors that experience delirium are at high risk for developing new functional disabilities and mental health disorders. We sought to determine if individual motoric subtypes of delirium are associated with worse disability, depression, and/or post-traumatic stress disorder in ICU survivors.

DESIGN

Secondary analysis of a prospective multicenter cohort study.

SETTING

Academic, community, and Veteran Affairs hospitals.

PATIENTS

Adult ICU survivors of respiratory failure and/or shock.

INTERVENTIONS

We assessed delirium and level of consciousness using the Confusion Assessment Method-ICU and Richmond Agitation and Sedation Scale daily during hospitalization. We classified delirium as hypoactive (Richmond Agitation and Sedation Scale ≤ 0) or hyperactive (Richmond Agitation and Sedation Scale > 0). At 3- and 12-month postdischarge, we assessed for dependence in activities of daily living and instrumental activities of daily living, symptoms of depression, and symptoms of post-traumatic stress disorder. Adjusting for baseline and inhospital covariates, multivariable regression examined the association of exposure to delirium motoric subtype and long-term outcomes.

MEASUREMENTS AND MAIN RESULTS

In our cohort of 556 adults with a median age of 62 years, hypoactive delirium was more common than hyperactive (68.9% vs 16.8%). Dependence on the activities of daily living was present in 37% at 3 months and 31% at 12 months, whereas dependence on instrumental activities of daily living was present in 63% at 3 months and 56% at 12 months. At both time points, depression and post-traumatic stress disorder rates were constant at 36% and 5%, respectively. Each additional day of hypoactive delirium was associated with higher instrumental activities of daily living dependence at 3 months only (0.24 points [95% CI, 0.07-0.41; p = 0.006]). There were no associations between the motoric delirium subtype and activities of daily living dependence, depression, or post-traumatic stress disorder.

CONCLUSIONS

Longer duration of hypoactive delirium, but not hyperactive, was associated with a minimal increase in early instrumental activities of daily living dependence scores in adult survivors of critical illness. Motoric delirium subtype was neither associated with early or late activities of daily living functional dependence or mental health outcomes, nor late instrumental activities of daily living functional dependence.

Special Considerations for the Aging Brain and Perioperative Neurocognitive Dysfunction

Postoperative delirium and postoperative cognitive dysfunction (POCD) occur commonly in older adults after surgery and are frequently underrecognized. Delirium has been associated with worse outcomes, and both delirium and cognitive dysfunction increase the risk of long-term cognitive decline. Although the pathophysiology of delirium and POCD have not been clearly defined, risk factors for both include increasing age, lower levels of education, and baseline cognitive impairment. In addition, developing delirium increases the risk of POCD. This article examines interventions that may reduce the risk of developing delirium and POCD and improve long-term recovery and outcomes in the vulnerable older population.