Regional lung perfusion using different indicators in electrical impedance tomography.

Management of acute respiratory distress syndrome (ARDS) is classically guided by protecting the injured lung and mitigating damage from mechanical ventilation. Yet the natural history of ARDS is also dictated by disruption in lung perfusion. Unfortunately, diagnosis and treatment are hampered by the lack of bedside perfusion monitoring. Electrical impedance tomography is a portable imaging technique that can estimate regional lung perfusion in experimental settings from the kinetic analysis of a bolus of an indicator with high conductivity. Hypertonic sodium chloride has been the standard indicator. However, hypertonic sodium chloride is often inaccessible in the hospital, limiting practical adoption. We investigated whether regional lung perfusion measured using electrical impedance tomography is comparable between indicators. Using a swine lung injury model, we determined regional lung perfusion (% of total perfusion) in five pigs, comparing 12% sodium chloride to 8.4% sodium bicarbonate across stages of lung injury and experimental conditions (body position, positive end-expiratory pressure). Regional lung perfusion for four lung regions was determined from maximum slope analysis of the indicator-based impedance signal. Estimates of regional lung perfusion between indicators were compared in the lung overall and within four lung regions. Regional lung perfusion estimated with a sodium bicarbonate indicator agreed with a hypertonic sodium chloride indicator overall (mean bias 0%, limits of agreement -8.43%, 8.43%) and within lung quadrants. The difference in regional lung perfusion between indicators did not change across experimental conditions. Sodium bicarbonate may be a comparable indicator to estimate regional lung perfusion using electrical impedance tomography.NEW & NOTEWORTHY Electrical impedance tomography is an emerging tool to measure regional lung perfusion using kinetic analysis of a conductive indicator. Hypertonic sodium chloride is the standard agent used. We measured regional lung perfusion using another indicator, comparing hypertonic sodium chloride to sodium bicarbonate in an experimental swine lung injury model. We found strong agreement between the two indicators. Sodium bicarbonate may be a comparable indicator to measure regional lung perfusion with electrical impedance tomography.

Motor Vehicle Crash Risk among Adults Undergoing General Surgery: A Retrospective Case-crossover Study.

BACKGROUND: Surgery causes transient impairment in cognition and function, which may impact driving safety. The authors hypothesized that the risk of a motor vehicle crash would increase after compared to before surgery. METHODS: The authors performed a nested case-crossover study within population-based observational data from the New Jersey Safety Health Outcomes Data Warehouse. The study included adults 18 yr or older with a valid driver's license who underwent general surgery in an acute care hospital in New Jersey between January 1, 2016, and November 30, 2017, and were discharged home. Individuals served as their own controls within a presurgery interval (56 days to 28 days before surgery) and postsurgery interval (discharge through 28 days after surgery). General surgery was defined by Common Procedural Terminology Codes. The primary outcome was a police-reported motor vehicle crash. RESULTS: In a cohort of 70,722 drivers, the number of crashes after surgery was 263 (0.37%) compared to 279 (0.39%) before surgery. Surgery was not associated with a change in crash incidence greater than 28 days using a case-crossover design (adjusted incidence rate ratio, 0.92; 95% CI, 0.78 to 1.09; P = 0.340). Statistical interaction was present for sex and hospital length of stay. Younger versus older adults (adjusted risk ratio, 1.87; 95% CI, 1.10 to 3.18; P = 0.021) and non-Hispanic Black individuals (adjusted risk ratio, 1.96; 95% CI, 1.33 to 2.88; P = 0.001) and Hispanic individuals (adjusted risk ratio, 1.38; 95% CI, 1.00 to 1.91; P = 0.047) versus non-Hispanic White individuals had a greater risk of a crash after surgery. CONCLUSIONS: Using population-based crash and hospital discharge data, the incidence of motor vehicle crashes over a 28-day period did not change on average before compared to after surgery. The authors provide data on crash risk after surgery and highlight specific populations at risk.

Preoperative Sedative-hypnotic Medication Use and Adverse Postoperative Outcomes.

OBJECTIVE: To determine the association between preoperative benzodiazepine and nonbenzodiazepine receptor agonist ("Z-drugs") use and adverse outcomes after surgery. BACKGROUND: Prescriptions for benzodiazepines and Z-drugs have increased over the past decade. Despite this, the association of preoperative benzodiazepines and Z-drug receipt with adverse outcomes after surgery is unknown. METHODS: Using the Optum Clinformatics Datamart, we performed a retrospective cohort study of adults 18 years or older who underwent any of 10 common surgical procedures between 2010 and 2015. The principal exposure was one or more filled prescriptions for a benzodiazepine or Z-drug in the 90 days before surgery. The primary outcome was any emergency department visit or hospital admission for either (1) a drug related adverse medical event or overdose or (2) a traumatic injury in the 30 days after surgery. RESULTS: Of 785,346 patients meeting inclusion criteria, 94,887 (12.1%) filled a preoperative prescription for a benzodiazepine or Z-drug. From multivariable logistic regression, benzodiazepine or Z-drug use was associated with an increased odds of an adverse postoperative event [odds ratio 1.13; 95% confidence interval: 1.08-1.18). In a separate regression, coprescription of benzodiazepines or Z-drugs with opioids was associated with a 1.45 odds of an adverse postoperative event (95% confidence interval: 1.37-1.53). CONCLUSIONS: Preoperative benzodiazepines and Z-drug use is common and associated with increased odds of adverse outcomes after surgery, particularly when coprescribed with opioids. Counseling on appropriate benzodiazepine and Z-drug use in advance of elective surgery may potentially increase the safety of surgical care.

Observational Study of the Associations of Participation in High School Football With Self-Rated Health, Obesity, and Pain in Adulthood.

American football is the most popular high school sport in the United States, yet its association with health in adulthood has not been widely studied. We investigated the association between high school football and self-rated health, obesity, and pain in adulthood in a retrospective cohort study of data from the Wisconsin Longitudinal Study (1957-2004). We matched 925 males who played varsity football in high school with 1,521 males who did not play football. After matching, playing football was not associated with poor or fair self-rated health (odds ratio (OR) = 0.88, 95% confidence interval (CI): 0.63, 1.24; P = 0.48) or pain that limited activities (OR = 0.86, 95% CI: 0.59, 1.25; P = 0.42) at age 65 years. Football was associated with obesity (body mass index (weight (kg)height (m)2) ≥30) in adulthood (OR = 1.32, 95% CI: 1.06, 1.64; P = 0.01). The findings suggest that playing football in high school was not significantly associated with poor or fair self-related health at age 65 years, but it was associated with the risk of being obese as an adult in comparison with not playing football in high school. Our findings provide needed information about the risk of playing football with regard to a broader set of health outcomes.

Prevalence and Multivariable Factors Associated With Preoperative Cognitive Impairment in Outpatient Surgery in the United States.

Preoperative cognitive impairment increases the risk of adverse events after surgery but its prevalence in outpatient surgery has not been defined. We aimed to determine the prevalence and multivariable factors associated with cognitive impairment in individuals who present for outpatient surgery. We used data from the Health and Retirement Study, a longitudinal panel survey of older Americans. Of 1836 participants who reported having outpatient surgery, we found that 16.1% had evidence of cognitive impairment. Significant multivariable factors associated with preoperative cognitive impairment included non-Hispanic African American race, prior stroke, preoperative functional dependence, and lower socioeconomic status and education level.

The older adult with preexisting neurocognitive disorder.

PURPOSE OF REVIEW: With the ageing population, there is an increasing number of patients with a neurocognitive disorder (NCD) who undergo surgical procedures. The aim of this review is to highlight the epidemiology of preoperative NCD. RECENT FINDINGS: New guidelines have defined NCD into mild NCD and major NCD consistent with terminology from the wider clinical community. Several assessment tools have been used in the preoperative setting to identify patients with evidence of cognitive decline. NCD prior to surgery remains a major risk factor postoperative delirium. SUMMARY: Cognitive dysfunction is common prior to surgery. Awareness of dysfunction, especially when taking care of older adults, is critical given the high risk of complications in this population.

Association Between Obesity, Age, and Functional Decline in Survivors of Cardiac Surgery.

BACKGROUND/OBJECTIVES: Little is known about the effect of obesity on functional decline after cardiac surgery, especially in elderly adults. Our goal was to determine the association between obesity and functional decline in the 2 years after cardiac surgery and the interaction between obesity and age. DESIGN: Retrospective cohort study. SETTING: The Health and Retirement Study, 2004-2014. PARTICIPANTS: U.S. adults aged 50 and older who indicated having cardiac surgery and had a body mass index (BMI) of 18.5 kg/m2 or greater (N = 1,731). MEASUREMENTS: BMI was classified as normal or overweight (18.5-29.9 kg/m2 ) and obese (≥30 kg/m2 ). Primary outcome was decline in ability to perform an activity of daily living (ADL) after surgery. RESULTS: Respondents had a median age of 71, 59.3% were female, and 34.3% were obese. Obese respondents had a higher incidence of ADL decline (22.4%) than those who were not obese (17.1%) (P = .007). In the multivariable analysis of our full cohort, obesity was not associated with ADL decline (odds ratio (OR)=1.20, 95% confidence interval (CI)=0.90-1.59, P = .21) after cardiac surgery, although obese respondents aged 50 to 79 had greater odds of ADL decline (OR=1.45, 95% CI=1.06-2.00, P = .02). Obese respondents aged 80 and older had nonstatistically significantly lower odds of ADL decline (OR=0.61, 95% CI=0.30-1.24, P = .18) compared to non-obese respondents. CONCLUSION: The association between obesity and postoperative functional decline in survivors of cardiac surgery differed according to age. Additional research is needed to identify interventions to improve outcomes in groups of older adults in whom obesity may increase the risk of postoperative functional decline.

Administrative issues to ensure safe anesthesia care in the office-based setting.

PURPOSE OF REVIEW: Office-based practice is distinct from other ambulatory practices and has unique considerations for an effective administrative structure to support its operations. RECENT FINDINGS: National guidelines have been promulgated by various entities addressing both management and clinical care aspects of the practice. Specific regulations vary by practice location, and practitioners need to comply with the pertinent accreditation and licensing requirements. Anesthesiologists have been at the forefront of promoting the culture of safety in the office-based setting. Specific practice considerations include provider credentialing, maintenance of documentation, quality assessment, professional liability, facility safety, patient health information, billing, and finance. Although there is emerging literature linking office accreditation to improved patient outcomes, more work is needed in this area. SUMMARY: Office-based practice will continue to evolve with the national emphasis on patient safety, cost reduction, value-based care, and outcomes measurement and reporting. Each practice must comply with the state and national regulations that could limit the types of procedures being performed and who can administer sedation or anesthesia, and require the facility to be accredited by a nationally recognized accrediting agency.