Epidemiology of anesthesia-related mortality in the United States, 1999-2005

Perspectives on Anesthesia and Perioperative Patient Safety: Past, Present, and Future

During the past 70 years, patient safety science has evolved through four organizational frameworks known as Safety-0, Safety -1, Safety-2, and Safety-3. Their evolution reflects the realization over time that blaming people, chasing errors, fixing one-offs, and regulation would not create the desired patient safety. In Safety-0, the oldest framework, harm events arise from clinician failure; event prevention relies on better staffing, education, and basic standards. In Safety-1, used by hospitals, harm events arise from individual and/or system failures. Safety is improved through analytics, workplace culture, high reliability principles, technology, and quality improvement. Safety-2 emphasizes clinicians' adaptability to prevent harm events in an everchanging environment, using resilience engineering principles. Safety-3, used by aviation, adds system design and control elements to Safety-1 and Safety-2, deploying human factors, design-thinking, and operational control or feedback to prevent and respond to harm events. Safety-3 represents a potential way for anesthesia and perioperative care to become safer.

Social Determinants of Health and Surgical Desirability of Outcome Ranking in Older Veterans

Importance

Evaluating how social determinants of health (SDOH) influence veteran outcomes is crucial, particularly for quality improvement.

Objective

To measure associations between SDOH, care fragmentation, and surgical outcomes using a Desirability of Outcome Ranking (DOOR).

Design, Setting, And Participants

This was a cohort study of US veterans using data from the Veterans Affairs (VA) Surgical Quality Improvement Program (VASQIP; 2013-2019) limited to patients aged 65 years or older with inpatient stays between 2 and 30 days, merged with multiple data sources, including Medicare. Race and ethnicity data were retrieved from VASQIP, Medicare and Medicaid beneficiary summary files, the Veterans Health Administration Corporate Data Warehouse, and the United States Veterans Eligibility Trends and Statistics file. Data were analyzed between September 2023 and February 2024.

Exposure

Living in a highly deprived neighborhood (Area Deprivation Index >85), race and ethnicity used as a social construct, rurality, and care fragmentation (percentage of non-VA care days).

Main Outcomes and Measures

DOOR is a composite, patient-centered ranking of 26 outcomes ranging from no complication (1, best) to 90-day mortality or near-death complications (6, worst). A series of proportional odds regressions was used to assess the impact of SDOH and care fragmentation adjusted for clinical risk factors, including presentation acuity (presenting with preoperative acute serious conditions and urgent or emergent surgical procedures).

Results

The cohort had 93 644 patients (mean [SD] age, 72.3 [6.2] years; 91 443 [97.6%] male; 74 624 [79.7%] White). Veterans who identified as Black (adjusted odds ratio [aOR], 1.06; 95% CI, 1.02-1.10; P = .048) vs White and veterans with higher care fragmentation (per 20% increase in VA care days relative to all care days: aOR, 1.01; 95% CI, 1.01-1.02; P < .001) were associated with worse (higher) DOOR scores until adjusting for presentation acuity. Living in rural geographic areas was associated with better DOOR scores than living in urban areas (aOR, 0.93; 95% CI, 0.91-0.96; P < .001), and rurality was associated with lower presentation acuity (preoperative acute serious conditions: aOR, 0.88; 95% CI, 0.81-0.95; P = .001). Presentation acuity was higher in veterans identifying as Black, living in deprived neighborhoods, and with increased care fragmentation.

Conclusions and Relevance

Veterans identifying as Black and veterans with greater proportions of non-VA care had worse surgical outcomes. VA programs should direct resources to reduce presentation acuity among Black veterans, incentivize veterans to receive care within the VA where possible, and better coordinate veterans' treatment and records between care sources.

Suppressive effect of the anesthetic propofol on the T cell function and T cell-dependent immune responses

General anesthesia is thought to suppress the immune system and negatively affect postoperative infection and the long-term prognosis of cancer. However, the mechanism underlying immunosuppression induced by general anesthetics remains unclear. In this study, we focused on propofol, which is widely used for sedation under general anesthesia and intensive care and examined its effects on the T cell function and T cell-dependent immune responses. We found that propofol suppressed T cell glycolytic metabolism, differentiation into effector T cells, and cytokine production by effector T cells. CD8 T cells activated and differentiated into effector cells in the presence of propofol in vitro showed reduced antitumor activity. Furthermore, propofol treatment suppressed the increase in the number of antigen-specific CD8 T cells during Listeria infection. In contrast, the administration of propofol improved inflammatory conditions in mouse models of inflammatory diseases, such as OVA-induced allergic airway inflammation, hapten-induced contact dermatitis, and experimental allergic encephalomyelitis. These results suggest that propofol may reduce tumor and infectious immunity by suppressing the T cell function and T cell-dependent immune responses while improving the pathogenesis and prognosis of chronic inflammatory diseases by suppressing inflammation.

PeriOperative Quality Initiative (POQI) international consensus statement on perioperative arterial pressure management

Arterial pressure monitoring and management are mainstays of haemodynamic therapy in patients having surgery. This article presents updated consensus statements and recommendations on perioperative arterial pressure management developed during the 11th POQI PeriOperative Quality Initiative (POQI) consensus conference held in London, UK, on June 4-6, 2023, which included a diverse group of international experts. Based on a modified Delphi approach, we recommend keeping intraoperative mean arterial pressure ≥60 mm Hg in at-risk patients. We further recommend increasing mean arterial pressure targets when venous or compartment pressures are elevated and treating hypotension based on presumed underlying causes. When intraoperative hypertension is treated, we recommend doing so carefully to avoid hypotension. Clinicians should consider continuous intraoperative arterial pressure monitoring as it can help reduce the severity and duration of hypotension compared to intermittent arterial pressure monitoring. Postoperative hypotension is often unrecognised and might be more important than intraoperative hypotension because it is often prolonged and untreated. Future research should focus on identifying patient-specific and organ-specific hypotension harm thresholds and optimal treatment strategies for intraoperative hypotension including choice of vasopressors. Research is also needed to guide monitoring and management strategies for recognising, preventing, and treating postoperative hypotension.

Wide-Awake Carpal Tunnel Release in the United States: Trends in Volume and Reimbursement by Operative Setting

BACKGROUND

Office-based surgery can increase logistical and financial efficiency for patients and surgeons. The current study compares wide-awake, office-based carpal tunnel release to wide-awake operations performed in the operating room in terms of volume, financial burden, narcotic prescriptions, and adverse events.

METHODS

Operations performed under local-only anesthesia from 2010 to 2020 were identified in a national administrative database (PearlDiver). Patients were grouped by surgical setting and matched based on age, sex, comorbidity burden, and geographic region. Primary endpoints included total disbursement and physician reimbursement, and 30-day narcotics prescriptions, emergency department (ED) visits, and surgical site infections (SSIs).

RESULTS

Before matching, there were 303,741 operating room operations and 5463 office operations. From 2010 to 2020, the percentage of operations in the office increased from 1.2% to 3.4%. Matched cohorts included 21,835 operating room operations and 5459 office operations. Office surgery was associated with lower total disbursement and physician reimbursement for patients with commercial insurance, Medicaid, and Medicare. Linear regression modeling indicated that office-based surgery was significantly associated with lower total disbursement and physician reimbursement. Fewer office patients filled narcotic prescriptions and visited the ED, and there was no difference in SSIs.

CONCLUSIONS

Compared with operating room surgery, office surgery was associated with lower financial burden, fewer narcotics prescriptions and ED visits, and a similar incidence of SSIs. These findings, together with literature showing greater efficiency in the office, suggest that office-based operations are safe and cost-effective and should continue to grow.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

The Outcome of the WALANT Technique in Primary Hand Flexor Tendons Repair

Introduction

Wide-awake local anesthesia and no tourniquet (WALANT) represents a revolutionary technique for hand surgeons who dismiss tourniquets and sedation. In this study, we present our experience with the WALANT technique in primary flexor tendon injuries of the hand.

Patient and methods

This prospective research was carried out on 30 patients undergoing hand primary, flexor tendon repair surgery. Flexor tendon injury zones 2, 3, 4, and 5 were included. WALANT was prepared and injected. The tendons were surgically managed by a cruciate single cross-stitched locked 4-strand technique. The pain was assessed using a visual analog scale (VAS) score. The range of motion (ROM) of affected fingers was assessed according to the Strickland evaluation system.

Results

There was a highly significant relationship between the patient's compliance with physiotherapy and obtained ROM of the affected finger with a P value <0.001. During injection of WALANT solution, 4 cases (13.3%) had no pain, 25 cases (83.3%) had mild pain (score 1-4), and 1 case (3.3%) had moderate pain (score 5-7).

Conclusion

WALANT provides an optimal bloodless and comfortable field with an opportunity to assess the strength of tendon repair, gapping or triggering and managing them intra-operatively.

Perioperative Risk of Noncardiac Surgery in Patients With Asymptomatic Significant Aortic Stenosis: A 10-Year Retrospective Study

BACKGROUND

Aortic stenosis (AS) is a representative geriatric disease, and there is an anticipated rise in the number of patients requiring noncardiac surgeries in patients with AS. However, there is still a lack of research on the primary predictors of noncardiac perioperative complications in patients with asymptomatic significant AS.

METHODS AND RESULTS

Among the cohort of noncardiac surgeries under general anesthesia, with an intermediate to high risk of surgery from 2011 to 2019, at Samsung Medical Center, 221 patients were identified to have asymptomatic significant AS. First, to examine the impact of significant AS on perioperative adverse events, the occurrences of major adverse cardiovascular events and perioperative adverse cardiovascular events were compared between patients with asymptomatic significant AS and the control group. Second, to identify the factors influencing the perioperative adverse events in patients with asymptomatic significant AS, a least absolute shrinkage and selection operator regression model was used. There was no significant difference between the control group and the asymptomatic significant AS group in the event rate of major adverse cardiovascular events (4.6% at control group versus 5.5% at asymptomatic significant AS group; P=0.608) and perioperative adverse cardiovascular events (13.8% at control group versus 18.3% at asymptomatic significant AS group; P=0.130). Cardiac damage stage was a significant risk factor of major adverse cardiovascular events and perioperative adverse cardiovascular events.

CONCLUSIONS

There was no significant difference in major postoperative cardiovascular events between patients with asymptomatic significant AS and the control group. Advanced cardiac damage stage in significant AS is an important factor in perioperative risk of noncardiac surgery.

Shift Volume Directly Impacts Neuroradiology Error Rate at a Large Academic Medical Center: The Case for Volume Limits

BACKGROUND AND PURPOSE

Unlike in Europe and Japan, guidelines or recommendations from specialized radiological societies on workflow management and adaptive intervention to reduce error rates are currently lacking in the United States. This study of neuroradiologic reads at a large US academic medical center, which may hopefully contribute to this discussion, found a direct relationship between error rate and shift volume.

MATERIALS AND METHODS

CT and MR imaging reports from our institution's Neuroradiology Quality Assurance database (years 2014-2020) were searched for attending physician errors. Data were collected on shift volume specific error rates per 1000 interpreted studies and RADPEER scores. Optimal cutoff points for 2, 3 and 4 groups of shift volumes were computed along with subgroups' error rates.

RESULTS

A total of 643 errors were found, 91.7% of which were clinically significant (RADPEER 2b, 3b). The overall error rate (errors/1000 examinations) was 2.36. The best single shift volume cutoff point generated 2 groups: ≤ 26 studies (error rate 1.59) and > 26 studies (2.58; OR: 1.63, P < .001). The best 2 shift volume cutoff points generated 3 shift volume groups: ≤ 19 (1.34), 20-28 (1.88; OR: 1.4, P = .1) and ≥ 29 (2.6; OR: 1.94, P < .001). The best 3 shift volume cutoff points generated 4 groups: ≤ 24 (1.59), 25-66 (2.44; OR: 1.54, P < .001), 67-90 (3.03; OR: 1.91, P < .001), and ≥ 91 (2.07; OR: 1.30, P = .25). The group with shift volume ≥ 91 had a limited sample size.

CONCLUSIONS

Lower shift volumes yielded significantly lower error rates. The lowest error rates were observed with shift volumes that were limited to 19-26 studies. Error rates at shift volumes between 67-90 studies were 226% higher, compared with the error rate at shift volumes of ≤ 19 studies.

"Burnout syndrome" in anesthesiologists and remedial measures- A narrative review

Anesthesiology, as an occupation, has its own unique sets of challenges, problems, issues, and circumstances, all leading to "occupational stress," which by now should be unequivocally accepted as a well-established fact. It is futile to continue pursuing research questions like, if there "really" is stress existing among practicing anesthesiologists/trainees, by conducting questionnaire-based surveys and doing meta-analyses. A significantly high incidence of existence of occupational stress in anesthesiologists is an undisputable and practical reality, which, when longstanding, gets culminated into "burnout syndrome" with its disastrous outcomes. Rather than pursuing the often-trodden path of finding the incidence, sources, and other superficial issues, an in-depth study of available literary evidence in relation to burnout has been carried out. Objectifying it as a "syndrome," its etiopathogenesis, pathophysiology inclusive of the prevalent theories of its causality, typology, and progression into various stages of/continuum of the process as an evolving clinical entity have been described. The preventive measures and "coping strategies" have been discussed at length in the end. It is the fervent hope and the desire of the authors that this discourse will sensitize all anesthesiologists, especially the younger and upcoming future generation, and help them avoid becoming a prey to this dreadful entity!

Anesthesiologists and Community Engagement: A Scoping Review of the Literature

Millions of individuals require anesthesia services each year. Although anesthesia-associated mortality rates have declined, anesthetic-related morbidity remains high, particularly among vulnerable populations. Disparities in perioperative screening, optimization, surveillance, and follow-up contribute to worse outcomes in these populations. Community-engaged collaborations may be the essential ingredient needed for anesthesiologists to improve disparities in anesthetic outcomes and prioritize the needs of patients and communities. This scoping review seeks to examine the available literature on community engagement among anesthesiologists to identify gaps and seek opportunities for future work. This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). OVID MEDLINE, Scopus, and Web of Science Core Collection were searched to identify sources that used or recognized community-engaged strategies and involved the work of anesthesiologists. Sources were selected based on inclusion criteria and consistent data were extracted from each paper for compilation in a data chart. The initial search generated 1230 articles of which 16 met criteria for inclusion in the review. An updated search of the literature and reference scan of included sources resulted in 7 additional articles being included. The sources were grouped according to overarching themes and methods used and ultimately categorized according to the spectrum of public participation developed by the International Association for Public Participation (IAP2). This spectrum includes 5 levels: inform, consult, involve, collaborate, and empower. This review identified 5 sources at the inform level, 8 studies in consult, 0 in involve, 7 in collaborate, and 3 in empower. Results indicate that most initiatives representing deeper levels of community engagement, at the collaborate or empower level, occur internationally. Efforts that occur in the United States tend to emphasize engagement of individual patients rather than communities. There is a need to pursue deeper, more meaningful community-engaged efforts within the field of anesthesiology at a local and national level.

Ultrasound (US)-guided percutaneous thrombin injection for stoma-site bleeding after PEG tube insertion: a case series and review of the literature

BACKGROUND

Post-gastrostomy bleeding sequelae are acknowledged, with reported approaches focusing on conservative measures or surgical repair. Nonetheless, Percutaneous Thrombin Injections (PTI) role in PEG-site-related bleeding remains underexplored. PTI under ultrasound guidance is an advocated management strategy for stoma-site bleeding following gastrostomy in high-risk patients, particularly those on direct oral anticoagulants.

CASE PRESENTATION

This study presents three cases with multiple comorbidities who underwent PTI. Resulting in immediate resolution of bleeding, no systemic\local effect, and no reported complications or rebleeding after a 3-6-month follow-up.

CONCLUSION

The findings highlight the safety, direct complete resolution, and absence of sequelae associated with PTI, suggesting its potential as a promising technique in managing PEG stoma-related bleeding.

Continuous vs intermittent Non-Invasive blood pressure MONitoring in preventing postoperative organ failure (niMON): study protocol for an open-label, multicenter randomized trial

BACKGROUND

Blood pressure has become one of the most important vital signs to monitor in the perioperative setting. Recently, the Italian Society of Anesthesia Analgesia Resuscitation and Intensive Care (SIAARTI) recommended, with low level of evidence, continuous monitoring of blood pressure during the intraoperative period. Continuous monitoring allows for early detection of hypotension, which may potentially lead to a timely treatment. Whether the ability to detect more hypotension events by continuous noninvasive blood pressure (C-NiBP) monitoring can improve patient outcomes is still unclear. Here, we report the rationale, study design, and statistical analysis plan of the niMON trial, which aims to evaluate the effect of intraoperative C-NiBP compared with intermittent (I-NiBP) monitoring on postoperative myocardial and renal injury.

METHODS

The niMon trial is an investigator-initiated, multicenter, international, open-label, parallel-group, randomized clinical trial. Eligible patients will be randomized in a 1:1 ratio to receive C-NiBP or I-NiBP as an intraoperative monitoring strategy. The proportion of patients who develop myocardial injury in the first postoperative week is the primary outcome; the secondary outcomes are the proportions of patients who develop postoperative AKI, in-hospital mortality rate, and 30 and 90 postoperative days events. A sample size of 1265 patients will provide a power of 80% to detect a 4% absolute reduction in the rate of the primary outcome.

CONCLUSIONS

The niMON data will provide evidence to guide the choice of the most appropriate intraoperative blood pressure monitoring strategy.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registration: NCT05496322, registered on the 5th of August 2023.

Perioperative quality indicators specific to the practice of anesthesia in noncardiac surgery: an umbrella review

PURPOSE

Improvement in delivery of perioperative care depends on the ability to measure outcomes that can direct meaningful changes in practice. We sought to identify and provide an overview of perioperative quality indicators specific to the practice of anesthesia in noncardiac surgery.

SOURCE

We conducted an umbrella review (a systematic review of systematic reviews) according to Joanna Briggs Institute methodology. We included systematic reviews examining perioperative indicators in patients ≥ 18 yr of age undergoing noncardiac surgery. Our primary outcome was any quality indicator specific to anesthesia. Indicators were classified by the Donabedian system and perioperative phase of care. The quality of systematic reviews was assessed using AMSTAR 2 criteria. Level of evidence of quality indicators was stratified by the Oxford Centre for Evidence-Based Medicine Classification.

PRINCIPAL FINDINGS

Our search returned 1,475 studies. After removing duplicates and screening of abstracts and full texts, 23 systematic reviews encompassing 3,164 primary studies met our inclusion criteria. There were 330 unique quality indicators. Process indicators were most common (n = 169), followed by outcome (n = 114) and structure indicators (n = 47). Few identified indicators were supported by high-level evidence (45/330, 14%). Level 1 evidence supported indicators of antibiotic prophylaxis (1a), venous thromboembolism prophylaxis (1a), postoperative nausea/vomiting prophylaxis (1b), maintenance of normothermia (1a), and goal-directed fluid therapy (1b).

CONCLUSION

This umbrella review highlights the scarcity of perioperative quality indicators that are supported by high quality evidence. Future development of quality indicators and recommendations for outcome measurement should focus on metrics that are supported by level 1 evidence. Potential targets for evidence-based quality-improvement programs in anesthesia are identified herein.

STUDY REGISTRATION

PROSPERO (CRD42020164691); first registered 28 April 2020.

Introduction of a Post-Anaesthesia Care Unit in a Teaching Hospital Is Associated with a Reduced Length of Hospital Stay in Noncardiac Surgery: A Single-Centre Interrupted Time Series Analysis

BACKGROUND

A post-anaesthesia care unit (PACU) may improve postoperative care compared with intermediate care units (IMCU) due to its dedication to operative care and an individualized duration of postoperative stay. The effects of transition from IMCU to PACU for postoperative care following intermediate to high-risk noncardiac surgery on length of hospital stay, intensive care unit (ICU) utilization, and postoperative complications were investigated.

METHODS

This single-centre interrupted time series analysis included patients undergoing eleven different noncardiac surgical procedures associated with frequent postoperative admissions to an IMCU or PACU between January 2018 and March 2019 (IMCU episode) and between October 2019 and December 2020 (PACU episode). Primary outcome was hospital length of stay, secondary outcomes included postoperative complications and ICU admissions.

RESULTS

In total, 3300 patients were included. The hospital length of stay was lower following PACU admission compared to IMCU admission (IMCU 7.2 days [4.2-12.0] vs. PACU 6.0 days [3.6-9.1]; p < 0.001). Segmented regression analysis demonstrated that the introduction of the PACU was associated with a decrease in hospital length of stay (GMR 0.77 [95% CI 0.66-0.91]; p = 0.002). No differences between episodes were detected in the number of postoperative complications or postoperative ICU admissions.

CONCLUSIONS

The introduction of a PACU for postoperative care of patients undergoing intermediate to high-risk noncardiac surgery was associated with a reduction in the length of stay at the hospital, without increasing postoperative complications.

The Effects of Antimicrobial Protocols and Other Perioperative Factors on Postoperative Complications in Horses Undergoing Celiotomy: A Retrospective Analysis, 2008-2021

Recognition of antimicrobial resistance in equine practice has increased over the past decade. The objective of this study was to provide an updated retrospective review of antimicrobial regimens in one tertiary referral hospital and to evaluate the association with postoperative complications. A secondary objective was to evaluate other perioperative factors including surgical procedure, anesthetic and recovery parameters, and the effect of perioperative medications on complications and outcomes. A computerized search of medical records was performed to identify horses undergoing exploratory celiotomy from 1 January 2008 to 31 December 2021. A total of 742 celiotomies were performed (608 completed, 134 terminated intraoperatively). Factors recorded were evaluated using logistic regression for the presence of either incisional infection, postoperative ileus, or other complications postoperatively. Antimicrobial type or timing (pre-, intra-, or postoperative) were not associated with decreased risk of incisional infection or postoperative ileus; however, the duration of NSAID use was positively associated with incisional infection (OR 1.14 per day). Lidocaine and alpha-2-agonist administration postoperatively were also associated with increased incidence of postoperative ileus (OR 21.5 and 1.56, respectively). Poor recovery quality (OR 4.69), the addition of other antimicrobials besides penicillin/gentamicin postoperatively (OR 3.63), and an increased number of different NSAID classes used (OR 1.46 per additional) were associated with other complications. Implementation of enterotomy was associated with decreased risk of other complications (OR 0.64). These findings provide an updated summary of factors associated with postoperative complications in horses undergoing celiotomy.

Incidence, severity and detection of blood pressure and heart rate perturbations in postoperative ward patients after noncardiac surgery

STUDY OBJECTIVE

We sought to determine changes in continuous mean and systolic blood pressure and heart rate in a cohort of non-cardiac surgical patients recovering on the postoperative ward. Furthermore, we estimated the proportion of vital signs changes that would remain undetected with intermittent vital signs checks.

DESIGN

Retrospective cohort.

SETTING

Post-operative general ward.

PATIENTS

14,623 adults recovering from non-cardiac surgical procedures.

INTERVENTIONS & MEASUREMENTS

Using a wireless, noninvasive monitor, we recorded postoperative blood pressure and heart rate at 15-s intervals and encouraged nursing intervention as clinically indicated.

MAIN RESULTS

7% of our cohort of 14,623 patients spent >15 sustained minutes with a MAP <65 mmHg, and 23% had MAP <75 mmHg for 15 sustained minutes. Hypertension was more common, with 67% of patients spending at least 60 sustained minutes with MAP >110 mmHg. Systolic pressures <90 mmHg were present for 15 sustained minutes in about a fifth of all patients, and 40% of patients had pressures >160 mmHg sustained for 30 min. 40% of patients were tachycardic with heart rates >100 beats/min for at least continuous 15 min and 15% of patients were bradycardic at a threshold of <50 beats/min for 5 sustained minutes. Conventional vital sign assessments at 4-h intervals would have missed 54% of mean pressure episodes <65 mmHg sustained >15 min, 20% of episodes of mean pressures >130 mmHg sustained >30 min, 36% of episodes of heart rate > 120 beats/min sustained <10 min, and 68% of episodes of heart rate sustained <40 beats per minute for >3 min.

CONCLUSIONS

Substantial hemodynamic disturbances persisted despite implementing continuous portable ward monitoring coupled with nursing alarms and interventions. A significant proportion of these changes would have gone undetected using traditional intermittent monitoring. Better understanding of effective responses to alarms and appropriate interventions on hospital wards remains necessary.

Machine Learning of Physiologic Waveforms and Electronic Health Record Data: A Large Perioperative Data Set of High-Fidelity Physiologic Waveforms

Perioperative morbidity and mortality are significantly associated with both static and dynamic perioperative factors. The studies investigating static perioperative factors have been reported; however, there are a limited number of previous studies and data sets analyzing dynamic perioperative factors, including physiologic waveforms, despite its clinical importance. To fill the gap, the authors introduce a novel large size perioperative data set: Machine Learning Of physiologic waveforms and electronic health Record Data (MLORD) data set. They also provide a concise tutorial on machine learning to illustrate predictive models trained on complex and diverse structures in the MLORD data set.

Anaesthesia-related mortality within 24 h following 9,391,669 anaesthetics in 10 cities in Hubei Province, China: a serial cross-sectional study

Background

The mortality risk related to anaesthesia in China remains poorly characterized. The objective of this study was to evaluate the anaesthesia-related mortality in terms of its incidence, changes, causes and preventability in Hubei, China, between 2017 and 2021 using a series of annual surveys.

Methods

We prospectively collected information on patient, surgical, anaesthesia, and hospital characteristics for 9,391,669 anaesthesia procedures performed between 2017 and 2021 in 10 cities within Hubei Province, China. Anaesthesia-related death was defined as death that deemed to be entirely or partially attributable to anaesthesia, occurring within 24 h following anaesthesia administration. All fatalities were scrutinized consecutively to determine their root causes and preventability. The incidence and patterns of anaesthesia-related deaths were analysed from 2017 to 2021. A mixed-effects model with a Poisson link function was fitted to evaluate the city-level annual changes in risk-adjusted incidence of anaesthesia-related deaths.

Findings

600 cases of anaesthetic deaths occurred from 2017 to 2021, yielding an incidence of 6.4 per 100,000 anaesthesia procedures [95% confidence interval (95% CI): 5.9, 6.9], and most were preventable (71.3%). There was a significant decrease from 2017 to 2021, in the incidences of anaesthesia-related death across all patients, those with American Society of Anaesthesiologists physical status (ASAPS) ≥III, and those who had general anaesthesia, with a percentage reduction of 57.6%, 59.1%, and 55.9%, respectively. The risk-adjusted annual changes indicated significant downward trends for the incidence of anaesthetic mortality from 2017 to 2018, 2019, 2020, and 2021. For instance, the risk-adjusted annual changes for the anaesthetic mortality incidence from 2017 to 2021 was -2.5 (95% CI: -1.4, -4.7).

Interpretation

In this large, comprehensive database study conducted in Central China, the anaesthesia-related death incidence was 6.4 per 100,000. Notably, the incidence of anaesthesia-related deaths decreased between 2017 and 2021. However, further in-depth analysis is needed to understand the extent to which these trends represent a change in patient safety.

Funding

Innovation and optimization of perioperative respiratory system management strategy (Hubei Technological Innovation Special Fund, 2019ACA167).

Most hospital patients at risk for bacterial infection undergo an anesthetic: implications for infection control practices related to the anesthesia workspace

PURPOSE

Even with nearly 100% compliance with prophylactic antibiotic protocols, many surgical patients (> 5%) develop surgical site infections, some caused by pathogens transmitted from the anesthesia workspace (e.g., anesthesia machine), including multidrug-resistant Staphylococcus aureus. Reducing contamination of the anesthesia workspace substantively reduces the risk of surgical site infections. We estimated the percentage of hospital patients at risk for health care-associated infections who may benefit from the application of basic preventive measures under the control of anesthesia practitioners (e.g., their hand hygiene).

METHODS

We conducted a retrospective cohort study which included every patient admitted to the University of Miami Health System from April 2021 through March 2022 for hospitalization, surgery, emergency department visits, or outpatient visits. Lists were created for the start date and times of every parenteral antibiotic administered and every anesthetic.

RESULTS

Among 28,213 patient encounters including parenteral antibiotic(s), more than half (64.3%) also included an anesthetic (99% confidence interval, 62.2 to 66.6). The hypothesis that most antibiotics were administered during encounters when a patient underwent an anesthetic was accepted (P < 0.001). This observation may seem counterintuitive because parenteral antibiotics were administered for fewer than half of the 53,235 anesthetics (34.2%). The result was a consequence of most anesthetics (63.5%) at the health system being conducted in nonoperating room locations, and only 7.2% of such patients received a parenteral antibiotic.

CONCLUSIONS

Because approximately two-thirds of patients who receive an intravenous antibiotic also undergo an anesthetic, greater use of effective infection control measures in the anesthesia operating room workspace has the potential to substantively reduce overall rates of hospital infections.

Dose-related adaptive reconstruction of DMN in isoflurane administration: a study in the rat

BACKGROUND

The anesthetic states are accompanied by functional alterations. However, the dose-related adaptive alterations in the higher-order network under anesthesia, e. g. default mode network (DMN), are poorly revealed.

METHODS

We implanted electrodes in brain regions of the rat DMN to acquire local field potentials to investigate the perturbations produced by anesthesia. Relative power spectral density, static functional connectivity (FC), fuzzy entropy of dynamic FC, and topological features were computed from the data.

RESULTS

The results showed that adaptive reconstruction was induced by isoflurane, exhibiting reduced static and stable long-range FC, and altered topological features. These reconstruction patterns were in a dose-related fashion.

CONCLUSION

These results might impart insights into the neural network mechanisms underlying anesthesia and suggest the potential of monitoring the depth of anesthesia based on the parameters of DMN.

Perioperative strategies to reduce risk of myocardial injury after non-cardiac surgery (MINS): A narrative review

Myocardial injury is a frequent complication of surgical patients after having non-cardiac surgery that is strongly associated with perioperative mortality. While intraoperative anesthesia-related deaths are exceedingly rare, about 1% of patients undergoing non-cardiac surgery die within the first 30 postoperative days. Given the number of surgeries performed annually, death following surgery is the second leading cause of death in the United States. Myocardial injury after non-cardiac surgery (MINS) is defined as an elevation in troponin concentrations within 30 days postoperatively. Although typically asymptomatic, patients with MINS suffer myocardial damage and have a 10% risk of death within 30 days after surgery and excess risks of mortality that persist during the first postoperative year. Many factors for the development of MINS are non-modifiable, such as preexistent coronary artery disease. Preventive measures, systematic approaches to surveillance and treatment standards are still lacking, however many factors are modifiable and should be considered in clinical practice: the importance of hemodynamic control, adequate oxygen supply, metabolic homeostasis, the use of perioperative medications such as statins, anti-thrombotic agents, beta-blockers, or anti-inflammatory agents, as well as some evidence regarding the choice of sedative and analgesic for anesthesia are discussed. Also, as age and complexity in comorbidities of the surgical patient population increase, there is an urgent need to identify patients at risk for MINS and develop prevention and treatment strategies. In this review, we provide an overview of current screening standards and promising preventive options in the perioperative setting and address knowledge gaps requiring further investigation.

Risk of anesthesia-related complications in draft horses: a retrospective, single-center analysis

OBJECTIVE

To report anesthetic-related complications and determine risks associated with anesthesia in draft horses.

STUDY DESIGN

Retrospective study.

ANIMALS

A total of 401 anesthetic records for draft horse breeds that underwent general anesthesia from January 2010 through December 2020 were reviewed; horses euthanized during general anesthesia were excluded.

METHODS

Demographics, perioperative drugs used, procedure type and duration, time to extubation, number of attempts to stand, use of sling in recovery and perioperative morbidity and mortality were investigated. Morbidity and mortality statistical evaluation included univariable logistic regression analysis and ordinal regression analysis.

RESULTS

American Society of Anesthesiologists (ASA) status I-II, ASA III-V and total mortality rate for all cases was 0.69% (2/288), 6.19% (7/113) and 2.24% (9/401), respectively, with Belgian horses being overrepresented (6/9). Cardiac arrest occurred in six out of nine horses that died without euthanasia, and five out of six of these horses underwent colic surgery. Factors associated with increased mortality risk included ASA status of III-V, increased body weight, emergency status and horses presenting for colic. Hypotension, hypercarbia and hypoxemia occurred in 56% (224/401), 46% (186/401) and 14% (58/401) of horses, respectively. During recovery from anesthesia, lighter horses and horses undergoing shorter anesthetic procedures were more likely to be successful on the first or second attempt to stand and were less likely to require a sling in recovery.

CONCLUSIONS AND CLINICAL RELEVANCE

Draft horses undergoing general anesthesia had a higher mortality rate than previously reported for all types and breeds of horses.

Meeting Report: First Cardiovascular Outcomes Research in Perioperative Medicine Conference

The first Cardiovascular Outcomes Research in Perioperative Medicine (COR-PM) conference took place on May 13, 2022, in Palm Springs, CA, and online. Here, we: (1) summarize the background, objective, and aims of the COR-PM meeting; (2) describe the conduct of the meeting; and (3) outline future directions for scientific meetings aimed at fostering high-quality clinical research in the broader perioperative medicine community.

The Evolution of Equipment and Technology for Visualising the Larynx and Airway

Laryngoscopy and endotracheal intubation are the core skills of an anaesthetist. The tools and equipment used today are unrecognisable from the methods used in the first recorded attempts at laryngoscopy over 200 years ago. The evolution of the modern-day laryngoscopes has mirrored advancements in technology within general society, and particularly with regard to computer and fibreoptic technology over the last 30 years. The development of these modern visualisation devices would not have been possible without those that went before it, as each new device has been influenced by the previous. Video laryngoscopes have quickly gained popularity as the primary intubating device in many scenarios, driven by ease of use as well as positive patient outcomes. While it is still debated whether videolaryngoscopes can replace direct laryngoscopy for routine intubations, their effectiveness in difficult airways is unquestioned. This chapter will cover the anatomy of the airway and the development of technology from the rudimentary creations in the early 1700s to the modern larynsgocopes created in the twenty-second century which allow the user to view the airway in more detail in order to secure endotracheal intubation even in an airway where intubation would be difficult.

A New Predictive Model for In-Hospital Major Adverse Cardiac and Cerebrovascular Events in Chinese Patients After Major Noncardiac Surgery

Prediction tools focused on cardiovascular and cerebrovascular events after noncardiac surgery are lacking, particularly for Chinese patients. We developed and validated what we believe is a new predictive tool for postoperative major cardiovascular and cerebrovascular events (MACCEs) in Chinese patients in this study. Overall, 401 variables derived from 598 patients who received noncardiac surgery at our center were retrospectively analyzed to develop and validate the new predictive model for MACCEs during hospitalization. The 7 strongest predictors for MACCEs in the development cohort were chronic heart failure, age, atrial fibrillation, general anesthesia, history of coronary heart disease, high-risk procedures, and lymphocyte count. The area under the receiver operating characteristic curve was 0.698 (95% confidence interval 0.616 to 0.780) for the new predictive tool with the validation cohort. Receiver operating characteristic curve analysis showed the new predictive tool had better performance than the Revised Cardiac Risk Index and the American College of Surgeons National Surgical Quality Improvement Program scores. This new predictive tool is effective for the prediction of postoperative MACCEs in patients who undergo noncardiac surgery.

Risk factors for mortality of medical causes within 30 days of electroconvulsive therapy

BACKGROUND

Electroconvulsive therapy (ECT) is used to treat severe psychiatric disorders and is associated with reduced risk of suicide and all-cause mortality in patients with severe depression. We investigated the causes of death occurring shortly after ECT and identified potential risk factors for medical causes of death.

METHODS

Patients treated with ECT between 2012 and 2018 were included in this Swedish register-based study. Multivariate binary logistic regression was used to calculate odds ratios for covariates to determine potential predictors of 30-day mortality.

RESULTS

Of the 20,225 included patients, 93 (0.46 %) died of suicide and 123 (0.61 %) died of medical causes after ECT. Cardiovascular disease was the most common medical cause of death (n = 49, 40 %). An older age, a Charlson Comorbidity Index of 1 or more, atrial fibrillation, kidney disease, reflux disease, dementia, and cancer were associated with increased risk of death by medical causes.

LIMITATIONS

Real-life observational studies based on registry data may demonstrate associations, but cannot determine causality. If medical records had been available, we would be better able to determine if deaths were due to the ECT, anesthesia, pre-existing medical conditions, or the mental disorder.

CONCLUSIONS

ECT appears to be a low-risk medical procedure. Older individuals with severe somatic diseases have the highest risk of death and extra measures should be considered to optimize their medical health during the pre-ECT workup, and during and after ECT.

The state of surgery, obstetrics, trauma, and anaesthesia care in Ghana: a narrative review

Background

Conditions amenable to surgical, obstetric, trauma, and anaesthesia (SOTA) care are a major contributor to death and disability in Ghana. SOTA care is an essential component of a well-functioning health system, and better understanding of the state of SOTA care in Ghana is necessary to design policies to address gaps in SOTA care delivery.

Objective

The aim of this study is to assess the current situation of SOTA care in Ghana.

Methods

A situation analysis was conducted as a narrative review of published scientific literature. Information was extracted from studies according to five health system domains related to SOTA care: service delivery, workforce, infrastructure, finance, and information management.

Results

Ghanaians face numerous barriers to accessing quality SOTA care, primarily due to health system inadequacies. Over 77% of surgical operations performed in Ghana are essential procedures, most of which are performed at district-level hospitals that do not have consistent access to imaging and operative room fundamentals. Tertiary facilities have consistent access to these modalities but lack consistent access to oxygen and/or oxygen concentrators on-site as well as surgical supplies and anaesthetic medicines. Ghanaian patients cover up to 91% of direct SOTA costs out-of-pocket, while health insurance only covers up to 14% of the costs. The Ghanaian surgical system also faces severe workforce inadequacies especially in district-level facilities. Most specialty surgeons are concentrated in urban areas. Ghana’s health system lacks a solid information management foundation as it does not have centralized SOTA databases, leading to incomplete, poorly coded, and illegible patient information.

Conclusion

This review establishes that surgical services provided in Ghana are focused primarily on district-level facilities that lack adequate infrastructure and face workforce shortages, among other challenges. A comprehensive scale-up of Ghana’s surgical infrastructure, workforce, national insurance plan, and information systems is warranted to improve Ghana’s surgical system.

Development and implementation of databases to track patient and safety outcomes

PURPOSE OF REVIEW

Recent advancements in big data analytical tools and large patient databases have expanded tremendously the opportunities to track patient and safety outcomes.We discuss the strengths and limitations of large databases and implementation in practice with a focus on the current opportunities to use technological advancements to improve patient safety.

RECENT FINDINGS

The most used sources of data for large patient safety observational studies are administrative databases, clinical registries, and electronic health records. These data sources have enabled research on patient safety topics ranging from rare adverse outcomes to large cohort studies of the modalities for pain control and safety of medications. Implementing the insights from big perioperative data research is augmented by automating data collection and tracking the safety outcomes on a provider, institutional, national, and global level. In the near future, big data from wearable devices, physiological waveforms, and genomics may lead to the development of personalized outcome measures.

SUMMARY

Patient safety research using large databases can provide actionable insights to improve outcomes in the perioperative setting. As datasets and methods to gain insights from those continue to grow, adopting novel technologies to implement personalized quality assurance initiatives can significantly improve patient care.

Association between postoperative acute kidney injury and mortality after plastic and reconstructive surgery

Acute kidney injury (AKI) is a common postoperative disorder that is associated with considerable morbidity and mortality. Although the role of AKI as an independent risk factor for mortality has been well characterized in major surgeries, its effect on postoperative outcomes in plastic and reconstructive surgery has not been evaluated. This study explored the association between postoperative AKI and mortality in patients undergoing plastic and reconstructive surgery. Consecutive adult patients who underwent plastic and reconstructive surgery without end-stage renal disease (n = 7059) at our institution from January 2011 to July 2019 were identified. The patients were divided into two groups according to occurrence of postoperative AKI: 7000 patients (99.2%) in the no AKI group and 59 patients (0.8%) in the AKI group. The primary outcome was mortality during the first year, and overall mortality and 30-days mortality were also compared. After inverse probability weighting, mortality during the first year after plastic and reconstructive surgery was significantly increased in the AKI group (1.9% vs. 18.6%; hazard ratio, 6.69; 95% confidence interval, 2.65-16.85; p < 0.001). In this study, overall and 30-day mortalities were shown to be higher in the AKI group, and further studies are needed on postoperative AKI in plastic and reconstructive surgery.

Management of patients susceptible to malignant hyperthermia: A surgeon's perspective

OBJECTIVES

Malignant hyperthermia (MH) susceptibility caries broad implications for the care of pediatric surgical patients. While precautions must often be taken for only a vague family history, two options exist to assess MH-susceptibility. We evaluate the use of MH precautions and susceptibility testing at a freestanding children's hospital.

METHODS

This single institution retrospective cohort study identified patients of any age who received general anesthetics utilizing MH precautions over a five-year period. The electronic medical record was further queried for patients diagnosed with MH. The indication for MH precautions and uses of susceptibility testing are assessed. Secondary outcomes included a diagnosis of bona fide MH.

RESULTS

A total of 125 patients received 174 anesthetics with MH precautions at a mean age of 114 months (0-363 months). Otolaryngology was the procedural service most frequently involved in the care of the cohort (n = 45; 26%). A reported personal or family history of MH (n = 102; 59%) was the most common indication for precautions, followed by muscular dystrophy (n = 29; 17%). No MH events occurred in the cohort and further review of ICD-9 and -10 diagnosis codes found no MH diagnoses. No study subjects received muscle biopsy and contracture testing and only 5 (4%) underwent genetic testing for genomic variants known to cause MH susceptibility. A case example is given to highlight the implications of a reported MH history.

CONCLUSION

Otolaryngologists should maintain a familiarity with the precautions necessary to manage patients at risk for MH and MH-like reactions. Without an accessible test to rule out susceptibility, surgeons must rely on a careful history to appropriately utilize precautions. An inappropriate label of "MH-susceptible" may result in decreased access to care and treatment delays.

Nationwide multidisciplinary consensus on the clinical management of Merkel cell carcinoma: a Delphi panel

Merkel cell carcinoma (MCC) is a rare and highly aggressive cutaneous neuroendocrine carcinoma. The MCC incidence rate has rapidly grown over the last years, with Italy showing the highest increase among European countries. This malignancy has been the focus of active scientific research over the last years, focusing mainly on pathogenesis, new therapeutic trials and diagnosis. A national expert board developed 28 consensus statements that delineated the evolution of disease management and highlighted the paradigm shift towards the use of immunological strategies, which were then presented to a national MCC specialists panel for review. Sixty-five panelists answered both rounds of the questionnaire. The statements were divided into five areas: a high level of agreement was reached in the area of guidelines and multidisciplinary management, even if in real life the multidisciplinary team was not always represented by all the specialists. In the diagnostic pathway area, imaging played a crucial role in diagnosis and initial staging, planning for surgery or radiation therapy, assessment of treatment response and surveillance of recurrence and metastases. Concerning diagnosis, the usefulness of Merkel cell polyomavirus is recognized, but the agreement and consensus regarding the need for cytokeratin evaluation appears greater. Regarding the areas of clinical management and follow-up, patients with MCC require customized treatment. There was a wide dispersion of results and the suggestion to increase awareness about the adjuvant radiation therapy. The panelists unanimously agreed that the information concerning avelumab provided by the JAVELIN Merkel 200 study is adequate and reliable and that the expanded access program data could have concrete clinical implications. An immunocompromised patient with advanced MCC can be treated with immunotherapy after multidisciplinary risk/benefit assessment, as evidenced by real-world analysis and highlighted in the guidelines. A very high consensus regarding the addition of radiotherapy to treat the ongoing focal progression of immunotherapy was observed. This paper emphasizes the importance of collaboration and communication among the interprofessional team members and encourages managing patients with MCC within dedicated multidisciplinary teams. New insights in the treatment of this challenging cancer needs the contribution of many and different experts.

Clinical Importance of Potential Genetic Determinants Affecting Propofol Pharmacokinetics and Pharmacodynamics

Interindividual variability in response to drugs used in anesthesia has long been considered the rule, not the exception. It is important to mention that in anesthesiology, the variability in response to drugs is multifactorial, i.e., genetic and environmental factors interact with each other and thus affect the metabolism, efficacy, and side effects of drugs. Propofol (2,6-diisopropylphenol) is the most common intravenous anesthetic used in modern medicine. Individual differences in genetic factors [single nucleotide polymorphisms (SNPs)] in the genes encoding metabolic enzymes, molecular transporters, and molecular binding sites of propofol can be responsible for susceptibility to propofol effects. The objective of this review (through the analysis of published research) was to systematize the influence of gene polymorphisms on the pharmacokinetics and pharmacodynamics of propofol, to explain whether and to what extent the gene profile has an impact on variations observed in the clinical response to propofol, and to estimate the benefit of genotyping in anesthesiology. Despite the fact that there has been a considerable advance in this type of research in recent years, which has been largely limited to one or a group of genes, interindividual differences in propofol pharmacokinetics and pharmacodynamics may be best explained by the contribution of multiple pathways and need to be further investigated.

[Intraoperative Hemodynamic Monitoring and Management]

Postoperative deaths are a consequence of postoperative complications - including acute kidney injury and myocardial injury. Postoperative complications are associated with non-modifiable patient-specific risk factors (i.e., age, medical history), but also with potentially modifiable risk factors - including intraoperative hypotension and compromised intraoperative blood flow. Based on patient- and surgery-specific risk factors, the intraoperative hemodynamic monitoring strategy needs to be selected. Intraoperative hypotension is associated with postoperative organ failure and should thus be avoided. To optimize intraoperative hemodynamics, cardiac output-guided hemodynamic management has been proposed. Cardiac output-guided hemodynamic management aims at optimizing oxygen delivery using fluids, vasopressors, and inotropes. Cardiac output-guided hemodynamic management has been shown to reduce postoperative complications compared to routine hemodynamic management in high-risk patients having major surgery.

User perceptions of different monitor modalities during high-fidelity simulation: Visual-Patient-avatar, Split Screen and Conventional - a semiquantitative analysis

Background

Patient safety during anesthesia is crucially dependent on the monitoring of vital signs. However, the values obtained must also be perceived and correctly classified by the attending care providers. To facilitate these processes, we developed Visual-Patient-avatar, an animated virtual model of the monitored patient, which innovatively presents numerical and waveform data following user-centered design principles. After a high-fidelity simulation study, we analyzed the participants’ perceptions of 3 different monitor modalities, including this newly introduced technique.

Objective

The aim of this study was to collect and evaluate participants’ opinions and experiences regarding 3 different monitor modalities, which are Visual-Patient-avatar, Split Screen (avatar and Conventional monitor alongside each other), and Conventional monitor after using them during simulated critical anesthetic events.

Methods

This study was a researcher-initiated, single-center, semiquantitative study. We asked 92 care providers right after finishing 3 simulated emergency scenarios about their positive and negative opinions concerning the different monitor modalities. We processed the field notes obtained and derived the main categories and corresponding subthemes following qualitative research methods.

Results

We gained a total of 307 statements. Through a context-based analysis, we identified the 3 main categories of “Visual-Patient-avatar,” “Split Screen,” and “Conventional monitor” and divided them into 11 positive and negative subthemes. We achieved substantial interrater reliability in assigning the statements to 1 of the topics. Most of the statements concerned the design and usability features of the avatar or the Split Screen mode.

Conclusions

This study semiquantitatively reviewed the clinical applicability of the Visual-Patient-avatar technique in a high-fidelity simulation study and revealed the strengths and limitations of the avatar only and Split Screen modality. In addition to valuable suggestions for improving the design, the requirement for training prior to clinical implementation was emphasized. The responses to the Split Screen suggest that this symbiotic modality generates better situation awareness in combination with numerical data and accurate curves. As a subsequent development step, a real-life introduction study is planned, where we will test the avatar in Split Screen mode under actual clinical conditions.

Impact of Intraoperative Data on Risk Prediction for Mortality After Intra-Abdominal Surgery

BACKGROUND

Risk prediction models for postoperative mortality after intra-abdominal surgery have typically been developed using preoperative variables. It is unclear if intraoperative data add significant value to these risk prediction models.

METHODS

With IRB approval, an institutional retrospective cohort of intra-abdominal surgery patients in the 2005 to 2015 American College of Surgeons National Surgical Quality Improvement Program was identified. Intraoperative data were obtained from the electronic health record. The primary outcome was 30-day mortality. We evaluated the performance of machine learning algorithms to predict 30-day mortality using: 1) baseline variables and 2) baseline + intraoperative variables. Algorithms evaluated were: 1) logistic regression with elastic net selection, 2) random forest (RF), 3) gradient boosting machine (GBM), 4) support vector machine (SVM), and 5) convolutional neural networks (CNNs). Model performance was evaluated using the area under the receiver operator characteristic curve (AUROC). The sample was randomly divided into a training/testing split with 80%/20% probabilities. Repeated 10-fold cross-validation identified the optimal model hyperparameters in the training dataset for each model, which were then applied to the entire training dataset to train the model. Trained models were applied to the test cohort to evaluate model performance. Statistical significance was evaluated using P < .05.

RESULTS

The training and testing cohorts contained 4322 and 1079 patients, respectively, with 62 (1.4%) and 15 (1.4%) experiencing 30-day mortality, respectively. When using only baseline variables to predict mortality, all algorithms except SVM (area under the receiver operator characteristic curve [AUROC], 0.83 [95% confidence interval {CI}, 0.69-0.97]) had AUROC >0.9: GBM (AUROC, 0.96 [0.94-1.0]), RF (AUROC, 0.96 [0.92-1.0]), CNN (AUROC, 0.96 [0.92-0.99]), and logistic regression (AUROC, 0.95 [0.91-0.99]). AUROC significantly increased with intraoperative variables with CNN (AUROC, 0.97 [0.96-0.99]; P = .047 versus baseline), but there was no improvement with GBM (AUROC, 0.97 [0.95-0.99]; P = .3 versus baseline), RF (AUROC, 0.96 [0.93-1.0]; P = .5 versus baseline), and logistic regression (AUROC, 0.94 [0.90-0.99]; P = .6 versus baseline).

CONCLUSIONS

Postoperative mortality is predicted with excellent discrimination in intra-abdominal surgery patients using only preoperative variables in various machine learning algorithms. The addition of intraoperative data to preoperative data also resulted in models with excellent discrimination, but model performance did not improve.

Anaesthesia's legacy: carpe diem

Intraoperative mortality is now rare. In contrast, 30-day postoperative mortality remains common, with most deaths occurring during the initial hospitalisation. The legacy of anaesthesiology will be determined by our success in dealing with postoperative mortality, which is currently the major problem in perioperative medicine. Carpe diem!

Using Lean tools to improve the efficiency of awake fibreoptic intubation setup

Background

Awake fibreoptic intubation is a complex advanced airway technique used by anaesthesiologists in the management of a difficult airway. The time to setup this important procedure can be significant which may dissuade its use by some providers. In our institution, the awake intubation setup process was highly variable and error prone.

Methods

We deployed Lean methods to improve the efficiency and accuracy of the awake fibreoptic intubation setup process. A 2-day improvement event with a multidisciplinary team addressed the setup process, tested solutions and created standard work documents. Twenty awake fibreoptic intubation simulations were conducted before and after the intervention to quantify gains in setup efficiency and error reduction.

Results

Variability in the setup process, including clinical locations visited, was reduced through creating a standardised process. The average time to for an awake fibreoptic intubation setup was reduced by approximately 50%, from 23 min to 11 min (p<0.001). In addition, awake fibreoptic intubation equipment set out without error increased in the postintervention simulations from 59% to 85% (p=0.003).

Conclusion

Using Lean tools, we were able to make the setup of awake fibreoptic intubation not only more efficient, but also more accurate. A similar methodological approach may have value for other complex anaesthesia procedures.

Self-Identified Patient Barriers to Pursuit of Cochlear Implantation

INTRODUCTION

Cochlear implantation (CI) is an underutilized treatment for hearing loss in the United States for reasons which remain unclear. This study explores self-identified barriers to CI employing a survey of adults who qualified for CI.

METHODS

A single-institutional review of CI candidates between December 2010 and December 2018 was performed to identify patients who did not pursue surgery. A 21-question survey was developed, aimed at rating patients' concerns regarding CI, including surgical risks, adaptation, costs, time commitment, loss of residual hearing, and lack of benefit, among others. Current hearing aid usage and familiarity with other CI users were also analyzed. The survey was administered to patients who did not pursue CI and a control group who eventually did pursue CI, via email or telephone.

RESULTS

There were 199 patients who initially did not pursue CI. Fifty-two survey responses were received, comprised of 27 patients who did not pursue CI and 25 patients who did. A belief that CI would not significantly improve the ability to communicate was the most common reported barrier, followed by the postoperative recovery process, risks of surgery, and risks of losing music appreciation. Anesthetic risk and cost were the least important reasons not to pursue CI. Half of patients reported concerns regarding the period of adjustment with the CI.

CONCLUSION

The decision not to pursue CI despite eligibility is multifactorial and includes concern for minimal hearing benefit and perioperative risks. These factors should be taken into consideration when counseling patients on CI surgery.

Litigation in Anesthesia and Intensive Care Units: An Italian Retrospective Study

Anesthesiologists consider professional insurance and its medico-legal problems as a remarkable aspect of their job. “Associazione Anestesisti Rianimatori Ospedalieri Italiani—Emergenza ed Area Critica” (AAROI-EMAC) is the Italian professional association of anesthesiologists and intensivists that works to train its subscribers on safety measures. This is a retrospective observational study on an insurance complaints database for anesthetic accidents that result in injuries to patients. The analyzed period runs from 1 January 2014 to 31 December 2016. A total of 1309 complaints related to 873 insurance claims were analyzed. Criminal complaints comprised 805 (64.4%) of the total, and civil complaints were 445 (35.6%). The iatrogenic damage claimed included: death (58% of the cases); peripheral nerve damage (8%); spinal cord injuries (5%); unspecified injuries (7%); dental damage (4%); infections (3%); needing second surgical procedure (2%); and other injuries (13%). There is a statistical significance between the size of the hospital and the number of the claims: small hospital complaints comprised 40.1% of the cases, while complaints against medium-sized and large hospitals constituted 20.6% of the cases (χ²GL = 8 = 39.87, p = 0.00). In Italy, anesthesiologists and intensivists are often involved in litigation even when they are not directly responsible for iatrogenic injuries, and the most frequent claims in ICU are related post-operative complications.

Tribute to Dr. Takuo Aoyagi, inventor of pulse oximetry

Introduction

Dr. Takuo Aoyagi invented pulse oximetry in 1974. Pulse oximeters are widely used worldwide, most recently making headlines during the COVID-19 pandemic. Dr. Aoyagi passed away on April 18, 2020, aware of the significance of his invention, but still actively searching for the theory that would take his invention to new heights.

Method

Many people who knew Dr. Aoyagi, or knew of him and his invention, agreed to participate in this tribute to his work. The authors, from Japan and around the world, represent all aspects of the development of medical devices, including scientists and engineers, clinicians, academics, business people, and clinical practitioners.

Results

While the idea of pulse oximetry originated in Japan, device development lagged in Japan due to a lack of business, clinical, and academic interest. Awareness of the importance of anesthesia safety in the US, due to academic foresight and media attention, in combination with excellence in technological innovation, led to widespread use of pulse oximetry around the world.

Conclusion

Dr. Aoyagi’s final wish was to find a theory of pulse oximetry. We hope this tribute to him and his invention will inspire a new generation of scientists, clinicians, and related organizations to secure the foundation of the theory.

Levels of Evidence Supporting the North American and European Perioperative Care Guidelines for Anesthesiologists between 2010 and 2020: A Systematic Review

BACKGROUND

Although there are thousands of published recommendations in anesthesiology clinical practice guidelines, the extent to which these are supported by high levels of evidence is not known. This study hypothesized that most recommendations in clinical practice guidelines are supported by a low level of evidence.

METHODS

A registered (Prospero CRD42020202932) systematic review was conducted of anesthesia evidence-based recommendations from the major North American and European anesthesiology societies between January 2010 and September 2020 in PubMed and EMBASE. The level of evidence A, B, or C and the strength of recommendation (strong or weak) for each recommendation was mapped using the American College of Cardiology/American Heart Association classification system or the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The outcome of interest was the proportion of recommendations supported by levels of evidence A, B, and C. Changes in the level of evidence over time were examined. Risk of bias was assessed using Appraisal of Guidelines for Research and Evaluation (AGREE) II.

RESULTS

In total, 60 guidelines comprising 2,280 recommendations were reviewed. Level of evidence A supported 16% (363 of 2,280) of total recommendations and 19% (288 of 1,506) of strong recommendations. Level of evidence C supported 51% (1,160 of 2,280) of all recommendations and 50% (756 of 1,506) of strong recommendations. Of all the guidelines, 73% (44 of 60) had a low risk of bias. The proportion of recommendations supported by level of evidence A versus level of evidence C (relative risk ratio, 0.93; 95% CI, 0.18 to 4.74; P = 0.933) or level of evidence B versus level of evidence C (relative risk ratio, 1.63; 95% CI, 0.72 to 3.72; P = 0.243) did not increase in guidelines that were revised. Year of publication was also not associated with increases in the proportion of recommendations supported by level of evidence A (relative risk ratio, 1.07; 95% CI, 0.93 to 1.23; P = 0.340) or level of evidence B (relative risk ratio, 1.05; 95% CI, 0.96 to 1.15; P = 0.283) compared to level of evidence C.

CONCLUSIONS

Half of the recommendations in anesthesiology clinical practice guidelines are based on a low level of evidence, and this did not change over time. These findings highlight the need for additional efforts to increase the quality of evidence used to guide decision-making in anesthesiology.

EDITOR’S PERSPECTIVE