Finger cuff versus invasive and noninvasive arterial pressure measurement in pregnant patients with obesity.

BACKGROUND: Pregnant patients with obesity may have compromised noninvasive blood pressure (NIBP) measurement. We assessed the accuracy and trending ability of the ClearSight™ finger cuff (FC) with invasive arterial monitoring (INV) and arm NIBP, in obese patients having cesarean delivery. METHODS: Participants were aged ≥18 years, ≥34 weeks gestation, and body mass index (BMI) ≥ 40 kg m-2. FC, INV, and NIBP measurements were obtained across 5-min intervals. The primary outcome was agreement of FC measurements with those of the reference standard INV, using modified Bland-Altman plots. Secondary outcomes included comparisons between FC and NIBP and NIBP versus INV, with four-quadrant plots performed to report discordance rates and evaluate trending ability. RESULTS: Twenty-three participants had a median (IQR) BMI of 45 kg m-2 (44-48). When comparing FC and INV the mean bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 16 mmHg (17, -17.3 to 49.3 mmHg), for diastolic blood pressure (DBP) -0.2 mmHg (10.5, -20.7 to 20.3), and for mean arterial pressure (MAP) 5.2 mmHg (11.1, -16.6 to 27.0 mmHg). Discordance occurred in 54 (26%) pairs for SBP, 41 (23%) for DBP, and 41 (21.7%) for MAP. Error grid analysis showed 92.1% of SBP readings in Zone A (no-risk zone). When comparing NIBP and INV, the mean bias (95% limits of agreement) for SBP was 13.0 mmHg (16.7, -19.7 to 29.3), for DBP 5.9 mmHg (11.9, -17.4 to 42.0), and for MAP 8.2 mmHg (11.9, -15.2 to 31.6). Discordance occurred in SBP (84 of 209, 40.2%), DBP (74 of 187, 39.6%), and MAP (63 of 191, 33.0%). CONCLUSIONS: The FC and NIBP techniques were not adequately in agreement with INV. Trending capability was better for FC than NIBP. Clinically important differences may occur in the setting of the perfusion-dependent fetus.

Time to Wake Up! The Ongoing Search for General Anesthetic Reversal Agents.

How general anesthetics work remains a topic of ongoing study. A parallel field of research has sought to identify methods to reverse general anesthesia. Reversal agents could shorten patients' recovery time and potentially reduce the risk of postoperative complications. An incomplete understanding of the mechanisms of general anesthesia has hampered the pursuit for reversal agents. Nevertheless, the search for reversal agents has furthered understanding of the mechanisms underlying general anesthesia. The study of potential reversal agents has highlighted the importance of rigorous criteria to assess recovery from general anesthesia in animal models, and has helped identify key arousal systems (e.g., cholinergic, dopaminergic, and orexinergic systems) relevant to emergence from general anesthesia. Furthermore, the effects of reversal agents have been found to be inconsistent across different general anesthetics, revealing differences in mechanisms among these drugs. The presynapse and glia probably also contribute to general anesthesia recovery alongside postsynaptic receptors. The next stage in the search for reversal agents will have to consider alternate mechanisms encompassing the tripartite synapse.

Supraglottic Airway Devices: Present State and Outlook for 2050.

Correct placement of supraglottic airway devices (SGDs) is crucial for patient safety and of prime concern of anesthesiologists who want to provide effective and efficient airway management to their patients undergoing surgery or procedures requiring anesthesia care. In the majority of cases, blind insertion of SGDs results in less-than-optimal anatomical and functional positioning of the airway devices. Malpositioning can cause clinical malfunction and result in interference with gas exchange, loss-of-airway, gastric inflation, and aspiration of gastric contents. A close match is needed between the shape and profile of SGDs and the laryngeal inlet. An adequate first seal (with the respiratory tract) and a good fit at the second seal of the distal cuff and the gastrointestinal tract are most desirable. Vision-guided insertion techniques are ideal and should be the way forward. This article recommends the use of third-generation vision-incorporated-video SGDs, which allow for direct visualization of the insertion process, corrective maneuvers, and, when necessary, insertion of a nasogastric tube (NGT) and/or endotracheal tube (ETT) intubation. A videoscope embedded within the SGD allows a visual check of the glottis opening and position of the epiglottis. This design affords the benefit of confirming and/or correcting a SGD's position in the midline and rotation in the sagittal plane. The first clinically available video laryngeal mask airways (VLMAs) and multiple prototypes are being tested and used in anesthesia. Existing VLMAs are still not perfect, and further improvements are recommended. Additional modifications in multicamera technology, to obtain a panoramic view of the SGD sitting correctly in the hypopharynx and to prove that correct sizes have been used, are in the process of production. Ultimately, any device inserted orally-SGD, ETT, NGT, temperature probe, transesophageal scope, neural integrity monitor (NIM) tubes-could benefit from correct vision-guided positioning. VLMAs also allow for automatic recording, which can be documented in clinical records of patients, and could be valuable during teaching and research, with potential value in case of legal defence (with an airway incident). If difficulties occur with the airway, documentation in the patient's file may help future anesthesiologists to better understand the real-time problems. Both manufacturers and designers of SGDs may learn from optimally positioned SGDs to improve the design of these airway devices.

Incidence and Factors Related to Prolonged Postoperative Cognitive Decline (POCD) in Elderly Patients Following Surgery and Anaesthesia: A Systematic Review.

Aim: The aim of this systematic review is to explore the current literature to provide evidence regarding the incidence and risk factors of prolonged POCD in elderly patients following cardiac and non-cardiac surgical interventions. Methods: The PubMed and Google Scholar databases were searched using appropriate keywords and search engines for adequate evidence from studies meeting the inclusion criteria so as to reveal the end-point, which was the presence of prolonged POCD in elderly patients following surgery and anaesthesia. The incidence of POCD at different time intervals and the variables predicting the occurrence of POCD were analysed. Results: The results of 23 articles covering 5077 patients (3694 non cardiac and 1383 cardiac surgeries) were carefully analysed. POCD occurs from the first postoperative day and lasts for potentially long periods. The incidence of POCD in this review ranged from 2.2% to 35.7%. More specifically, it ranged from 2.2% to 31.5% in non-cardiac surgeries and 11.8% to 35.7% in patients who had undergone cardiac surgeries. Some of the independent risk factors (predictors) for the development of POCD were advanced age, high concentration of neuroinflammatory mediators detectable in plasma, low SpO2, longer anaesthetic and surgical duration, and depth of anaesthesia. Conclusion: This review can only provide limited evidence of prolonged POCD (more than a year) and further research that involves better study designs, larger samples, involving longer follow-up, and at different sites (multicentre) is highly advised. This in turn may help researchers and clinicians to discover the actual causes and risk factors and develop appropriate preventive and treatment protocols to tackle POCD in the ageing surgical population.

The Internet, Apps, and the Anesthesiologist.

Modern anesthesia continues to be impacted in new and unforeseen ways by digital technology. Combining portability and versatility, mobile applications or "apps" provide a multitude of ways to enhance anesthetic and peri-operative care. Research suggests that the uptake of apps into anesthetic practice is becoming increasingly routine, especially amongst younger anesthetists brought up in the digital age. Despite this enthusiasm, there remains no consensus on how apps are safely and efficiently integrated into anesthetic practice. This review summarizes the most popular forms of app usage in anesthesia currently and explores the challenges and opportunities inherent in implementing app use in anesthesia, with an emphasis on a practical approach for the modern anesthetist.

A systematic review of predictive accuracy via c-statistic of preoperative frailty tests for extended length of stay, post-operative complications, and mortality.

Frailty, as an age-related syndrome of reduced physiological reserve, contributes significantly to post-operative outcomes. With the aging population, frailty poses a significant threat to patients and health systems. Since 2012, preoperative frailty assessment has been recommended, yet its implementation has been inhibited by the vast number of frailty tests and lack of consensus. Since the anesthesiologist is the best placed for perioperative care, an anesthesia-tailored preoperative frailty test must be simple, quick, universally applicable to all surgeries, accurate, and ideally available in an app or online form. This systematic review attempted to rank frailty tests by predictive accuracy using the c-statistic in the outcomes of extended length of stay, 3-month post-operative complications, and 3-month mortality, as well as feasibility outcomes including time to completion, equipment and training requirements, cost, and database compatibility. Presenting findings of all frailty tests as a future reference for anesthesiologists, Clinical Frailty Scale was found to have the best combination of accuracy and feasibility for mortality with speed of completion and phone app availability; Edmonton Frailty Scale had the best accuracy for post-operative complications with opportunity for self-reporting. Finally, extended length of stay had too little data for recommendation of a frailty test. This review also demonstrated the need for changing research emphasis from odds ratios to metrics that measure the accuracy of a test itself, such as the c-statistic.

Prevention and treatment of noncognitive complications.

Patients aged 65 and older are the fastest growing segment in the population of many countries. Based on evolving demographics showing increasing life expectancies, it is expected that there will be a concurrent rise in the demand for a large variety of surgical and anesthesia services. Surgery offers definitive management of many age-related diseases and provides symptom-relieving (morbidity) and life-extending (mortality) benefits. However, elderly adult surgical patients, especially the frail ones, often require a different level of care than younger patients during the perioperative period. As many have chronic illnesses and acquired deconditioning and functional decline, older patients are prone to develop untoward outcomes such as postoperative complications and loss of independence. This manuscript focuses on the holistic quality person-centered care, supported by a wide stakeholder team of health-care workers, ensuring fidelity to comprehensive geriatric assessment and optimization services where possible, offering a systematic approach to early health risk assessment and risk modification in the perioperative period, with the ultimate goal of reducing postoperative complications and health-care costs. The "comprehensive geriatric assessment and optimization" cost-effective approach builds on robust evidence with older people more likely to be alive, a shorter length of hospital stay due to fewer postoperative medical complications, and improved rates of return to usual residence. Prehabilitation programs are delivered focusing on primary (through counseling) and secondary prevention (through screening) with an aim to improve fitness for surgery, by evaluating functional capacity, nutritional and psychological health, prompting interventions, targeting physical exercise, lifestyle and nutritional advice, and psychological support.

Anesthesia and perioperative pain relief in the frail elderly patient.

Demand for anesthesia and analgesia for the frail elderly is continuously increasing as the likelihood of encountering very elderly, very vulnerable, and very compromised patients has, ever so subtly, increased over the last three decades. The anesthesiologist has, increasingly, been obliged to offer professional services to frail patients. Fortunately, there has been a dramatic improvement in medications, methods of drug delivery, critical monitoring, and anesthesia techniques. Specific methodologies peculiar to the frail are now taught and practiced across all anesthesia subspecialties. However, administering anesthesia for the frail elderly is vastly different to giving an anesthetic to the older patient. Frail patients are increasingly cared for in specialized units-geriatric intensive therapy units, post-acute care services, palliative, hospices, and supportive care and aged care facilities. Several medications (e.g., morphine-sparing analgesics) more suited to the frail have become universally available in most centers worldwide so that best-practice, evidence-based anesthesia combinations of drugs and techniques are now increasingly employed. Every anesthetic and pain management techniques in the frail elderly patient are going to be discussed in this review.

Transcutaneous carbon dioxide measurements in anesthetized apneic patients with BMI > 35 kg/m2.

Transcutaneous carbon dioxide measurement (TcCO2) offers the ability to continuously and non-invasively monitor carbon dioxide (CO2) tensions when end-tidal monitoring is not possible. The accuracy of TcCO2 has not been established in anesthetized apneic patients with obesity. In this secondary publication, we present a methods comparison analysis of TcCO2 with the gold standard arterial PCO2, in adult patients with body mass index (BMI) > 35kg/m2 who were randomized to receive high flow or low flow nasal oxygenation during post-induction apnea. Agreement between PaCO2 and TcCO2 at baseline, the start of apnea and the end of apnea were assessed using a non-parametric difference plot. Forty-two participants had a median (IQR) BMI of 52 (40-58.5) kg/m2. The mean (SD) PaCO2 was 33.9 (4.0) mmHg at baseline and 51.4 (7.5) mmHg at the end of apnea. The bias was the greatest at the end of apnea median (95% CI, 95% limits of agreement) 1.90 mmHg (-2.64 to 6.44, -7.10 to 22.90). Findings did not suggest significant systematic differences between the PaCO2 and TcCO2 measures. For a short period of apnea, TcCO2 showed inadequate agreement with PaCO2 in patients with BMI > 35 kg/m2. These techniques require comparison in a larger population, with more frequent sampling and over a longer timeframe, before TcCO2 can be confidently recommended in this setting.

Clinically Preferred Videolaryngoscopes in Airway Management: An Updated Systematic Review.

Videolaryngoscopes (VLs) have emerged as a safety net offering several advantages over direct laryngoscopy (DL). The aim of this study is to expand on our previous study conducted in 2016, to deduce which VL is most preferred by clinicians and to highlight any changes that may have occurred over the past 7 years. An extensive systematic literature review was performed on Medline, Embase, Web of Science, and Cochrane Central Database of Controlled Studies for articles published between September 2016 and January 2023. This review highlighted similar results to our study in 2016, with the CMAC being the most preferred for non-channelled laryngoscopes, closely followed by the GlideScope. For channelled videolaryngoscopes, the Pentax AWS was the most clinically preferred. This review also highlighted that there are minimal studies that compare the most-used VLs, and thus we suggest that future studies directly compare the most-used and -preferred VLs as well as the specific nature of blades to attain more useful results.

Intraoperative cell salvage: The impact on immune cell numbers.

BACKGROUND: Patient outcomes are influenced by many confounding factors peri-operatively, including the type of surgery, anaesthesia, transfusion, and immune competence. We have previously demonstrated (in-vitro) that compared to allogeneic blood transfusion (ABT), intraoperative cell salvage (ICS) improves immune competence. The peri-operative immune response is complex. Altered or impaired immune responses may predispose patients to develop adverse outcomes (i.e., post-operative wound infection, pneumonia, urinary tract infection etc.) Surgical patients may develop infection, even without the confirmed presence of a definite microbiological pathogen. With all these factors in mind it is important to consider changes in immune cell numbers (and sub-populations) and functional capacity during peri-operative transfusion. METHODS: In this TRIMICS-Cell (Transfusion Related Immune Modulation and Intraoperative Cell Salvage-Cell numbers) study (n = 17, October 2018-November 2019) we prioritized and analysed peri-operative changes in the number and proportions of immune cell populations and sub-populations (B cells (CD20+), NK (natural killer) cells (CD56+), monocytes (CD14+), T cells (total CD3+ and sub-populations: T helper cells (CD4+), cytotoxic T cells (CD8+), effector T cells (CD4+ CD127+), activated effector T cells (CD4+ CD25+ CD127+) and regulatory T cells (CD4+ CD25+ CD127-)), plasmacytoid dendritic cells (pDC; Lineage-, HLA-DR+, CD11c-, CD123+), classical dendritic cell (cDC) (Lineage-, HLA-DR+, CD11c+), and cDC activation (Lineage-, HLA-DR+, CD11c+), co-stimulatory/adhesion molecules and pDC (CD9+, CD38+, CD80+, CD83+, CD86+, CD123+). Firstly we analysed the whole cohort of study patients and secondly according to the relevant transfusion modality (i.e., three study groups: those who received no transfusion, received ICS only (ICS), or both ICS and allogeneic packed red blood cells (pRBC) (ICS&RBC)), during major orthopaedic surgery. RESULTS: For the whole study cohort (all patients), changes in immune cell populations were significant: leucocytes and specifically neutrophils increased post-operatively, returning towards pre-operative numbers by 48h post-operatively (48h), and lymphocytes reduced post-operatively returning to pre-operative numbers by 48h. When considering transfusion modalities, there were no significant peri-operative changes in the no transfusion group for all immune cell populations studied (cell numbers and proportions (%)). Significant changes in cell population numbers (i.e., leucocytes, neutrophils and lymphocytes) were identified in both transfused groups (ICS and ICS&RBC). Considering all patients, changes in immune cell sub-populations (NK cells, monocytes, B cells, T cells and DCs) and functional characteristics (e.g., co-stimulation markers, adhesion, activation, and regulation) were significant peri-operatively and when considering transfusion modalities. Interestingly DC numbers and functional capacity were specifically altered following ICS compared to ICS&RBC and pDCs were relatively preserved post-operatively following ICS. CONCLUSION: A transient peri-operative alteration with recovery towards pre-operative numbers by 48h post-surgery was demonstrated for many immune cell populations and sub-populations throughout. Immune cell sub-populations and functional characteristics were similar peri-operatively in those who received no transfusion but changed significantly following ICS and ICS&RBC. Interesting changes that require future study are a post-operative monocyte increase in the ICS&RBC group, changes in cDC considering transfusion modalities, and possibly preserved pDC numbers post-operatively following ICS. Future studies to assess changes in immune cell sub-populations, especially during peri-operative transfusion, while considering post-operative adverse outcomes, is recommended.

Angiogenesis and Tissue Repair Depend on Platelet Dosing and Bioformulation Strategies Following Orthobiological Platelet-Rich Plasma Procedures: A Narrative Review.

Angiogenesis is the formation of new blood vessel from existing vessels and is a critical first step in tissue repair following chronic disturbances in healing and degenerative tissues. Chronic pathoanatomic tissues are characterized by a high number of inflammatory cells; an overexpression of inflammatory mediators; such as tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1); the presence of mast cells, T cells, reactive oxygen species, and matrix metalloproteinases; and a decreased angiogenic capacity. Multiple studies have demonstrated that autologous orthobiological cellular preparations (e.g., platelet-rich plasma (PRP)) improve tissue repair and regenerate tissues. There are many PRP devices on the market. Unfortunately, they differ greatly in platelet numbers, cellular composition, and bioformulation. PRP is a platelet concentrate consisting of a high concentration of platelets, with or without certain leukocytes, platelet-derived growth factors (PGFs), cytokines, molecules, and signaling cells. Several PRP products have immunomodulatory capacities that can influence resident cells in a diseased microenvironment, inducing tissue repair or regeneration. Generally, PRP is a blood-derived product, regardless of its platelet number and bioformulation, and the literature indicates both positive and negative patient treatment outcomes. Strangely, the literature does not designate specific PRP preparation qualifications that can potentially contribute to tissue repair. Moreover, the literature scarcely addresses the impact of platelets and leukocytes in PRP on (neo)angiogenesis, other than a general one-size-fits-all statement that "PRP has angiogenic capabilities". Here, we review the cellular composition of all PRP constituents, including leukocytes, and describe the importance of platelet dosing and bioformulation strategies in orthobiological applications to initiate angiogenic pathways that re-establish microvasculature networks, facilitating the supply of oxygen and nutrients to impaired tissues.

Diversity in medical PhD curricula: a call for harmonisation.

BACKGROUND: Globalisation has increased human movements around the world, spurring greater connectiveness and opportunities to collaborate. In an increasingly connected world, quality assurance among professionals is paramount, particularly in medical research where PhD (Doctor of Philosophy) degree holders are expected to be at the peak of their field and play advanced-level research, education and leadership roles. While some regional efforts have been made to ensure comparability in the standards of advanced degree training, no previous study has compared these standards for a PhD in medicine across the globe. AIMS: To explore the structural diversity of medical PhD degrees and identify which aspects benefit from greater harmonisation. METHODS: In 2021, the 10 best-ranked universities from each of the top five Western countries, and the top Asian country, were identified based on Quacquarelli Symonds World University Ranking. Data were collected for each university based on individual website information regarding the level of degree required to gain entry into a PhD programme in medicine and requirements for completion of coursework, journal publication and oral defence. RESULTS: Significant variations exist in the requirements for medical PhDs across the world in terms of prerequisite degree and inclusion of coursework. Oral defence is near universal, but a mandatory requirement for publication is largely absent. CONCLUSIONS: Harmonisation of medical PhD degrees through international standards should be considered to encourage quality improvement and benchmarking between institutions, as well as to facilitate greater ease of movement within the medical research community, improving international collaboration and individual career opportunities accordingly.

Ultrasound-Guided Axillary Brachial Plexus Block for the Management of Graft Site Pain During Dressing Change in the Burn-Injured Patient: A Randomized Control Trial.

Burn injuries requiring split-thickness skin grafting procedures often require ongoing wound aggravation in the form of dressing changes. These dressing changes may cause significant pain due to stimulation of damaged nerve endings in the epidermal layer. A randomized control trial, pilot study, was undertaken to evaluate the impact of ultrasound-guided regional nerve block on the outcome of patient reported pain scores by inpatients requiring dressing changes for hand and upper limb burn injuries. Twenty participants aged >18 years, requiring split-skin grafting for burn injuries of <15% total body surface area were enrolled from a tertiary burns unit between August 2018 and September 2020. Participants were randomized to control (10 participants) or intervention group (10 participants). All participants received analgesia as per their treating team, the intervention group received the addition of an ultrasound-guided axillary brachial plexus block prior to their dressing change procedure. The primary outcome was to assess perceived pain at the graft site as measured by the Numeric Pain Rating Scale (0-10) before, during, and after dressing change procedure. There was strong evidence of a difference in the adjusted mean change score between groups, with a mean reduction of 4.3 in the intervention group, indicating reduced pain, and a mean increase of 1.2 in the control group (P < .001). No adverse events occurred in either group, and the addition of ultrasound-guided regional anesthesia (RA) for the treatment of dressing pain was determined to be a safe and effective intervention.

Video laryngeal masks in airway management.

INTRODUCTION: Video laryngeal masks have become alternatives to classical supraglottic airway devices in recent years. This review provides information on the background of these new medical devices, the most popular and widely used video laryngeal masks, their advantages, disadvantages and their main applications in airway management. AREAS COVERED: In this review, the physical differences between video laryngeal masks and second-generation laryngeal mask airways, and their properties in specific clinical settings are discussed. EXPERT COMMENTARY: To limit airway-related morbidity, an optimal position of supraglottic airway devices must be the primary goal. Extensive research has shown that blindly inserted laryngeal mask can be malpositioned in 50% to 80% of the cases. Therefore, blind insertion should be the exception rather than the rule unlike current practice. Video laryngeal mask airways have clear advantages in routine use and in difficult airway management since they allow a vision-guided technique. Henceforth, the properties perceived in clinical practice must be endorsed with quality clinical evidence.

Demystifying the role of anaesthetists in clinical coding in the Australian healthcare system.

Despite the self-evident importance of hospital funding, many anaesthetists remain unsure of exactly how their daily work relates to hospital reimbursement. A lack of awareness of the nuances of the Australian hospital activity-based funding system has the potential to affect anaesthetic department reimbursement and thus resourcing. Activity-based funding relies on clinical coders reviewing clinical documentation and quantifying the care given to a patient during an admission. Errors in funding allocation may arise when there is a disconnect between the work performed and the information coded. In anaesthesia, there are several factors impeding this process, including clinical understanding of coding, system setup and coders' understanding of anaesthesia. This article explores these factors from the clinical anaesthetist's point of view and suggests solutions, such as awareness and education, clinician-coder cooperation and redesign of documentation systems at a systems level that anaesthetic departments can incorporate.