Challenges in reliable preoperative blood ordering: A qualitative interview study.

BACKGROUND: Presurgical blood orders are important for patient safety during surgery, but excess orders can be costly to patients and the healthcare system. We aimed to assess clinician perceptions on the presurgical blood ordering process and perceived barriers to reliable decision-making. METHODS: This descriptive qualitative study was conducted at a single large academic medical center. Semi-structured interviews were conducted with surgeons, anesthesiologists, nurse anesthetists, nurse practitioners working in preoperative assessment clinics, and transfusion medicine physicians to assess perceptions of current blood ordering processes. Interview responses were analyzed using an inductive open coding approach followed by thematic analysis. RESULTS: Twenty-three clinicians were interviewed. Clinicians felt that the current blood ordering process was frequently inconsistent. One contributor was a lack of information on surgical transfusion risk, related to lack of experience in ordering clinicians, insufficient communication between stakeholders, high turnover in academic settings, and lack of awareness of the maximum surgical blood ordering schedule. Other contributors included differing opinions about the benefits and harms of over- and under-preparing blood products, leading to variation in transfusion risk thresholds between clinicians, and disagreement about the safety of emergency-release blood. CONCLUSION: Several barriers to reliable decision-making for presurgical blood orders exist. Future efforts to improve ordering consistency may benefit from improved information sharing between stakeholders and education on safe transfusion practices.

Effect of machine learning models on clinician prediction of postoperative complications: the Perioperative ORACLE randomised clinical trial.

BACKGROUND: Anaesthesiologists might be able to mitigate risk if they know which patients are at greatest risk for postoperative complications. This trial examined the impact of machine learning models on clinician risk assessment. METHODS: This single-centre, prospective, randomised clinical trial enrolled surgical patients aged ≥18 yr. Anaesthesiologists and nurse anaesthetists providing remote telemedicine support reviewed electronic health records with (assisted group) or without (unassisted group) reviewing machine learning predictions. Clinicians predicted the likelihood of postoperative 30-day all-cause mortality and postoperative acute kidney injury (AKI) within 7 days. The primary outcome was area under the receiver operating characteristic curve (AUROC) for clinician predictions of mortality and AKI, comparing AUROCs between assisted and unassisted assessments. RESULTS: We analysed 5071 patients (mean [range] age: 58 [18-100] yr; 52% female) assessed by 89 clinicians. Of these, 98 (2.2%) patients died within 30 days of surgery and 450 (11.1%) patients sustained AKI. Clinician predictions agreed with the models more strongly in the assisted vs unassisted group (weighted kappa 0.75 vs 0.62 for death, mean difference: 0.13 [95% CI 0.10-0.17]; and 0.79 vs 0.54 for AKI, mean difference: 0.25 [95% CI 0.21-0.29]). Clinical prediction of death was similar between the assisted (AUROC 0.793) and unassisted (AUROC 0.780) groups (mean difference: 0.013 [95% CI -0.070 to 0.097]; P=0.76). Prediction of AKI had an AUROC of 0.734 in the assisted group vs 0.688 in the unassisted group (difference 0.046 [95% CI -0.003 to 0.091]; P=0.06). CONCLUSIONS: Clinician performance was not improved by machine learning assistance. Further work is needed to clarify the role of machine learning in real-time perioperative risk stratification. CLINICAL TRIAL REGISTRATION: NCT05042804.

Abnormal preoperative cognitive screening in aged surgical patients: a retrospective cohort analysis.

BACKGROUND: Preoperative cognitive dysfunction has been associated with adverse postoperative outcomes. There are limited data characterising the epidemiology of preoperative cognitive dysfunction in older surgical patients. METHODS: This retrospective cohort included all patients ≥65 yr old seen at the Washington University preoperative clinic between January 2013 and June 2018. Cognitive screening was performed using the Short-Blessed Test (SBT) and Eight-Item Interview to Differentiate Aging and Dementia (AD8) screen. The primary outcome of abnormal cognitive screening was defined as SBT score ≥5 or AD8 score ≥2. Multivariable logistic regression was used to identify associated factors. RESULTS: Overall, 21 666 patients ≥65 yr old completed screening during the study period; 23.5% (n=5099) of cognitive screens were abnormal. Abnormal cognitive screening was associated with increasing age, decreasing BMI, male sex, non-Caucasian race, decreased functional independence, and decreased metabolic functional capacity. Patients with a history of stroke or transient ischaemic attack, chronic obstructive pulmonary disease, diabetes mellitus, hepatic cirrhosis, and heavy alcohol use were also more likely to have an abnormal cognitive screen. Predictive modelling showed no combination of patient factors was able to reliably identify patients who had a <10% probability of abnormal cognitive screening. CONCLUSIONS: Routine preoperative cognitive screening of unselected aged surgical patients often revealed deficits consistent with cognitive impairment or dementia. Such deficits were associated with increased age, decreased function, decreased BMI, and several common medical comorbidities. Further research is necessary to characterise the clinical implications of preoperative cognitive dysfunction and identify interventions that may reduce related postoperative complications.

Sinus of Valsalva Aneurysms: A Review with Perioperative Considerations.

The sinuses of Valsalva are outpouchings in the aortic root just distal to the aortic valve that serve several physiologic functions. Aneurysm of this segment of the aorta is quite rare and infrequently encountered in clinical practice. Due to the rarity of sinus of Valsalva aneurysms, there is a lack of controlled trials and most of the literature consists of case reports and series. Here, the authors review the currently available literature to discuss the anatomy and normal function of the aortic root, as well as disease pathology and diagnostic imaging considerations. Using reported cases, the authors also will discuss considerations for cardiac anesthesiologists in the perioperative period.

Anesthetic Considerations for Transcatheter Tricuspid Valve Repair.

The development of transcatheter approaches for heart valve repair and replacement procedures have revolutionized the field of structural cardiology and cardiac anesthesiology. With the recently reported benefits of transcatheter mitral repair procedures, there has been increasing focus on transcatheter tricuspid repair technologies. Currently, there are multiple transcatheter tricuspid repair devices that are undergoing feasibility testing, and each device has its own unique procedural considerations. This review discusses the anesthetic management of transcatheter tricuspid repair by describing the causes of tricuspid regurgitation, the currently available transcatheter tricuspid repair devices, the procedural considerations relevant to the cardiac anesthesiologist, and pearls for proper intraprocedural image guidance via transesophageal echocardiography.

Acute Presentation of Bioprosthetic Mitral Valve Thrombosis in a Patient on Venoarterial Extracorporeal Membranous Oxygenation.

The management of patients presenting with bioprosthetic valve thrombosis presents a major clinical challenge from a diagnostic and management standpoint. This patient population becomes especially challenging to manage when presenting with cardiogenic shock and additional risks for bleeding. In this clinical conference, the authors present the case of a 64-year-old male who developed intraoperative bioprosthetic mitral valve thrombosis and cardiogenic shock necessitating support with venoarterial extracorporeal membrane oxygenation. The discussion focuses on the diagnostic challenges with transesophageal echocardiography and the difficulty in determining the proper approach to systemic anticoagulation.

Anesthetic Considerations for Aortic Arch Stenting.

With advances in modern day imaging techniques for the aorta, there has been an increasing incidence of vascular diseases involving the aortic arch. Historically, the only treatment option for arch disease has been open arch replacement under circulatory arrest conditions with or without selective cerebral perfusion. However, this open procedure has significant morbidity and mortality, especially in elderly patients with multiple comorbidities. To potentially mitigate the risks associated with open replacement, endovascular arch repair has gained momentum as an alternative treatment option. Currently, aortic arch stenting is being trialed in multiple international medical centers across Europe and the United States. The outcomes data available thus far are promising, which suggest that there likely will be an increase in patients being referred for aortic arch stenting procedures in the future. In this emerging technology review, multiple aspects of the aortic arch stenting procedure are discussed including the currently available endovascular arch devices, the unique surgical and anesthetic considerations for arch stent implantation, and the early outcomes data published to date.

Anesthetic Considerations for the Transcatheter Management of Mitral Valve Disease.

The development of transcatheter interventions to provide a minimally invasive alternative to open surgical repair has revolutionized the care of patients with valvular heart disease. Recently, this technology has been expanded to allow for the treatment of pathology of the mitral valve. This review discusses the anesthetic considerations for patients presenting for transcatheter management of mitral valve disease, including transcatheter mitral valve replacement (TMVR) and transcatheter mitral valve repair (TMVRep). The initial focus is on the current literature on transcatheter interventions for mitral valve pathologies as well as current and developing technology for TMVR and TMVRep. The authors' institutional experience with anesthetic management for the TMVR and TMVRep procedures is described, including potential pitfalls and complications, concluding with a discussion of the role of transesophageal echocardiography in the care of this patient population.

The Perioperative Management of Ascending Aortic Dissection.

Acute aortic syndromes are a distinct group of pathologies involving the wall of the aorta that present acutely and can be potentially fatal unless treated in a timely fashion. The syndrome is dominated by aortic dissections, which comprise ≥95% of all such presentations. Those involving the ascending aorta are particularly lethal and require specific and early surgical treatment compared to dissections involving other parts of the aorta. The surgical repair of an ascending aortic dissection presents multiple challenges to the anesthesiologist. Thoughtful management throughout the perioperative period is critical for minimizing the significant morbidity and mortality associated with this condition. In this narrative review, we provide an overview of the perioperative management of patients presenting for the surgical repair of an ascending aortic dissection. Preoperative discussion focuses on assessment, hemodynamic management, and risk stratification. The intraoperative section includes an overview of anesthetic management, transesophageal echocardiographic assessment, and coagulopathy, as well as surgical considerations that may influence anesthetic management.

Anesthetic Considerations for Transcatheter Pulmonary Valve Replacement.

The introduction of transcatheter therapy for valvular heart disease has revolutionized the care of patients with valvular disorders. Pathologic regurgitation or stenosis of the pulmonary valve, right ventricular outflow tract, or a right ventricle-to-pulmonary artery conduit represent emerging indications for transcatheter therapy. To date, minimal literature exists detailing the anesthetic management of patients undergoing transcatheter pulmonary valve replacement. In this review, the pathophysiology and indications for transcatheter pulmonary valve replacement and possible complications unique to this procedure are reviewed. Anesthetic management, including preoperative assessment, intraoperative considerations, and early postoperative monitoring, are discussed.

Ultrasound-Guided Suprainguinal Fascia Iliaca Technique Provides Benefit as an Analgesic Adjunct for Patients Undergoing Total Hip Arthroplasty.

Analgesia after total hip arthroplasty is often accomplished by the fascia iliaca compartment block, traditionally performed below the inguinal ligament, to anesthetize both femoral and lateral femoral cutaneous nerves. The course of the lateral femoral cutaneous nerve below the inguinal ligament is variable as opposed to consistent above the inguinal ligament in the pelvis. In this case series including 5 patients, we demonstrate that an ultrasound-guided suprainguinal fascia iliaca approach would consistently anesthetize the lateral femoral cutaneous nerve along with anterior cutaneous femoral nerve branches and provide cutaneous analgesia after total hip arthroplasty, as shown by decreased opioid consumption.

HCV epitope, homologous to multiple human protein sequences, induces a regulatory T cell response in infected patients.

BACKGROUND & AIMS: Spontaneous resolution of hepatitis C virus (HCV) infection depends upon a broad T cell response to multiple viral epitopes. However, most patients fail to clear infections spontaneously and develop chronic disease. The elevated number and function of CD3(+)CD4(+)CD25(+)FoxP3(+) regulatory T cells (T(reg)) in HCV-infected patients suggest a role of Treg cells in impaired viral clearance. The factors contributing to increased Treg cell activity in chronic hepatitis C cases remain to be delineated. METHODS: Immunoinformatics tools were used to predict promiscuous, highly-conserved HLA-DRB1-restricted immunogenic consensus sequences (ICS), each composed of multiple T cell epitopes. These sequences were synthesized and added to cultures of peripheral blood mononuclear cells (PBMCs), derived from patients who resolved HCV infection spontaneously, patients with persistent infection, and non-infected individuals. The cells were collected and following 5days incubation, quantified and characterized by flow cytometry. RESULTS: One immunogenic consensus sequence (ICS), HCV_G1_p7_794, induced a marked increase in Treg cells in PBMC cultures derived from infected patients, but not in patients who spontaneously cleared HCV or in non-infected individuals. An analogous human peptide (p7_794), on the other hand, induced a significant increase in Treg cells among PBMCs derived from both HCV-infected and non-infected individuals. JanusMatrix analyses determined that HCV_G1_p7_794 is comprised of Treg cell epitopes that exhibit extensive cross-reactivity with the human proteome. CONCLUSIONS: A virus-encoded peptide (HCV_G1_p7_794) with extensive human homology activates cross-reactive CD3(+)CD4(+)CD25(+)FoxP3(+) natural Treg cells, which potentially contributes to immunosuppression and to the development of chronic hepatitis C.

Enhanced in vivo targeting of murine nonparenchymal liver cells with monophosphoryl lipid A functionalized microcapsules.

A broad spectrum of infectious liver diseases emphasizes the need of microparticles for targeted delivery of immunomodulatory substances to the liver. Microcapsules (MCs) are particularly attractive for innovative drug and vaccine formulations, enabling the combination of antigen, drugs, and adjuvants. The present study aimed to develop microcapsules characterized by an enhanced liver deposition and accelerated uptake by nonparenchymal liver cells (NPCs). Initially, two formulations of biodegradable microcapsules were synthesized from either hydroxyethyl starch (HES) or mannose. Notably, HES-MCs accumulated primarily in the liver, while mannose particles displayed a lung preference. Functionalization of HES-MCs with anti-CD40, anti-DEC205, and/or monophosphoryl lipid A (MPLA) enhanced uptake of MCs by nonparenchymal liver cells in vitro. In contrast, only MPLA-coated HES-MCs promoted significantly the in vivo uptake by NPCs. Finally, HES-MCs equipped with MPLA, anti-CD40, and anti-DEC205 induced the secretion of TNF-α, IL-6 by Kupffer cells (KCs), and IFN-γ and IL-12p70 by liver dendritic cells (DCs). The enhanced uptake and activation of KCs by MPLA-HES-MCs is a promising approach to prevent or treat infection, since KCs are exploited as an entry gate in various infectious diseases, such as malaria. In parallel, loading and activating liver DCs, usually prone to tolerance, bears the potential to induce antigen specific, intrahepatic immune responses necessary to prevent and treat infections affecting the liver.

Increasing hepatitis C prevalence and associated risk behaviors among incarcerated young adults.

This study sought to assess the rate of hepatitis C virus (HCV) infection and associated risk factors in young adults 18-28 years of age who were incarcerated in the Rhode Island Department of Corrections. The majority of participants reported injection drug use and engaged in high-risk behaviors such as needle sharing. Despite having these risk factors and believing themselves to be at risk, the majority of youths reported no prior HCV testing. Correctional facilities present a unique opportunity to detect HCV infection and provide risk reduction education to young adults, the population with the highest rates of new infections in the US. Seventy-two incarcerated individuals with a history of drug use were approached to participate in the study; 68 completed the screening and interview. The rate of HCV infection among adults <30 years of age and incarcerated at the Rhode Island Department of Corrections in 2011 was high (24%). In 1998, the rate of HCV among inmates <30 years of age at the same facility was only 11.4%. These data follow the same increase in HCV infection rates among young adults observed in non-incarcerated young adults across the nation. HCV is the leading cause of liver failure and hepatocellular carcinoma in the US. Despite a decline and leveling in HCV incidence nationwide, alarming increases in HCV rates among adolescents and young adults have been reported during the period between the years 1992 and 2005. This disquieting epidemic is attributable to injection drug use amongst young adults.

Effect of Machine Learning on Anaesthesiology Clinician Prediction of Postoperative Complications: The Perioperative ORACLE Randomised Clinical Trial.

Background: Anaesthesiology clinicians can implement risk mitigation strategies if they know which patients are at greatest risk for postoperative complications. Although machine learning models predicting complications exist, their impact on clinician risk assessment is unknown. Methods: This single-centre randomised clinical trial enrolled patients age ≥18 undergoing surgery with anaesthesiology services. Anaesthesiology clinicians providing remote intraoperative telemedicine support reviewed electronic health records with (assisted group) or without (unassisted group) also reviewing machine learning predictions. Clinicians predicted the likelihood of postoperative 30-day all-cause mortality and postoperative acute kidney injury within 7 days. Area under the receiver operating characteristic curve (AUROC) for the clinician predictions was determined. Results: Among 5,071 patient cases reviewed by 89 clinicians, the observed incidence was 2% for postoperative death and 11% for acute kidney injury. Clinician predictions agreed with the models more strongly in the assisted versus unassisted group (weighted kappa 0.75 versus 0.62 for death [difference 0.13, 95%CI 0.10-0.17] and 0.79 versus 0.54 for kidney injury [difference 0.25, 95%CI 0.21-0.29]). Clinicians predicted death with AUROC of 0.793 in the assisted group and 0.780 in the unassisted group (difference 0.013, 95%CI -0.070 to 0.097). Clinicians predicted kidney injury with AUROC of 0.734 in the assisted group and 0.688 in the unassisted group (difference 0.046, 95%CI -0.003 to 0.091). Conclusions: Although there was evidence that the models influenced clinician predictions, clinician performance was not statistically significantly different with and without machine learning assistance. Further work is needed to clarify the role of machine learning in real-time perioperative risk stratification. Trial Registration: ClinicalTrials.gov NCT05042804.