Implanted System for Orthostatic Hypotension in Multiple-System Atrophy.

Orthostatic hypotension is a cardinal feature of multiple-system atrophy. The upright posture provokes syncopal episodes that prevent patients from standing and walking for more than brief periods. We implanted a system to restore regulation of blood pressure and enable a patient with multiple-system atrophy to stand and walk after having lost these abilities because of orthostatic hypotension. This system involved epidural electrical stimulation delivered over the thoracic spinal cord with accelerometers that detected changes in body position. (Funded by the Defitech Foundation.).

Cuffless Blood Pressure in clinical practice: challenges, opportunities and current limits.

Background: Cuffless blood pressure measurement technologies have attracted significant attention for their potential to transform cardiovascular monitoring.Methods: This updated narrative review thoroughly examines the challenges, opportunities, and limitations associated with the implementation of cuffless blood pressure monitoring systems.Results: Diverse technologies, including photoplethysmography, tonometry, and ECG analysis, enable cuffless blood pressure measurement and are integrated into devices like smartphones and smartwatches. Signal processing emerges as a critical aspect, dictating the accuracy and reliability of readings. Despite its potential, the integration of cuffless technologies into clinical practice faces obstacles, including the need to address concerns related to accuracy, calibration, and standardization across diverse devices and patient populations. The development of robust algorithms to mitigate artifacts and environmental disturbances is essential for extracting clear physiological signals. Based on extensive research, this review emphasizes the necessity for standardized protocols, validation studies, and regulatory frameworks to ensure the reliability and safety of cuffless blood pressure monitoring devices and their implementation in mainstream medical practice. Interdisciplinary collaborations between engineers, clinicians, and regulatory bodies are crucial to address technical, clinical, and regulatory complexities during implementation. In conclusion, while cuffless blood pressure monitoring holds immense potential to transform cardiovascular care. The resolution of existing challenges and the establishment of rigorous standards are imperative for its seamless incorporation into routine clinical practice.Conclusion: The emergence of these new technologies shifts the paradigm of cardiovascular health management, presenting a new possibility for non-invasive continuous and dynamic monitoring. The concept of cuffless blood pressure measurement is viable and more finely tuned devices are expected to enter the market, which could redefine our understanding of blood pressure and hypertension.

This review explores cuffless blood pressure technologies and their impact on clinical practice, highlighting innovative devices that offer non-invasive, continuous and non-continuous monitoring without a cuff. Signal processing is essential for ensuring accurate readings, as it filters out unwanted artifacts and environmental disturbances which could make the reading inaccurate. While these advancements show great potential for transforming cardiovascular care, there are still several challenges to overcome, including the need for standardized protocols and validation studies to ensure their reliability and safety in clinical settings. Collaborative efforts between engineers, clinicians, and regulatory bodies are needed to address the technical and regulatory complexities surrounding the implementation of these technologies. These cuffless blood pressure measurement devices have the potential to reshape how we understand and manage blood pressure and hypertension.

Videolaryngoscopy use before and after the initial phases of the COVID-19 pandemic: The report of the VL-iCUE survey with responses from 96 countries.

BACKGROUND: The potential benefit of videolaryngoscopy use in facilitating tracheal intubation has already been established, however its use was actively encouraged during the COVID-19 pandemic as it was likely to improve intubation success and increase the patient-operator distance. OBJECTIVES: We sought to establish videolaryngoscopy use before and after the early phases of the pandemic, whether institutions had acquired new devices during the COVID-19 pandemic, and whether there had been teaching on the devices acquired. DESIGN: We designed a survey with 27 questions made available via the Joint Information Scientific Committee JISC online survey platform in English, French, Spanish, Chinese, Japanese and Portuguese. This was distributed through 18 anaesthetic and airway management societies. SETTING: The survey was open for 54 to 90 days in various countries. The first responses were logged on the databases on 28 October 2021, with all databases closed on 26 January 2022. Reminders to participate were sent at the discretion of the administering organisations. PARTICIPANTS: All anaesthetists and airway managers who received the study were eligible to participate. MAIN OUTCOME MEASURES: Videolaryngoscopy use before the COVID-19 pandemic and at the time of the survey. RESULTS: We received 4392 responses from 96 countries: 944/4336 (21.7%) were from trainees. Of the 3394 consultants, 70.8% (2402/3394) indicated no change in videolaryngoscopy use, 19.9% (675/3394) increased use and 9.3% (315/3393) reduced use. Among trainees 65.5% (618/943) reported no change in videolaryngoscopy use, 27.7% (261/943) increased use and 6.8% (64/943) reduced use. Overall, videolaryngoscope use increased by 10 absolute percentage points following the pandemic. CONCLUSIONS: Videolaryngoscopy use increased following the early phase of the COVID-19 pandemic but this was less than might have been expected.

Hypnosis in the operating room: are anesthesiology teams interested and well-informed?

BACKGROUND: Hypnosis can be a beneficial complementary anesthesia technique for a variety of surgical procedures. Despite favorable scientific evidence, hypnosis is still rarely used in the operating room. Obstacles to implementation could be a lack of interest or training, misconceptions, as well as limited knowledge amongst anesthesiology teams. Hence, this study aimed to assess the interest, training, beliefs, and knowledge about hypnosis in the operating room staff. DESIGN: A questionnaire with 21-items, based on a prior survey, was set up on an online platform. The medical and nursing anesthesiology staff of four Swiss academic and large regional hospitals (N = 754) were invited to participate anonymously through e-mails sent by their hierarchy. Results were analyzed quantitatively. RESULTS: Between June, 2020 and August, 2021 353 answers were collected (47% response rate). Most (92%) were aware that hypnosis needs specific training, with 14% trained. A large majority of the untrained staff wished to enroll for conversational hypnosis training. There was a strong agreement for hypnosis playing a role in anesthesia. Nevertheless, many of these professionals believed that hypnosis has a limited field of action (53%) or that it would be too time consuming (33%). The reduction of misconceptions was based more on exposure to hypnosis than on training. CONCLUSION: Overall, anesthesia providers' attitude was in favor of using hypnosis in the operating room. Misconceptions such as a prolongation of the procedure, alteration of consent, lack of acceptability for patients, and limited indications were identified as potential barriers. These deserve to be challenged through proper dissemination of the recent scientific literature and exposure to practice.

Evaluation of a novel optical smartphone blood pressure application: a method comparison study against invasive arterial blood pressure monitoring in intensive care unit patients.

BACKGROUND: Arterial hypertension is a worldwide public health problem. While it is currently diagnosed and monitored non-invasively using the oscillometric method, having the ability to measure blood pressure (BP) using a smartphone application could provide more widespread access to hypertension screening and monitoring. In this observational study in intensive care unit patients, we compared blood pressure values obtained using a new optical smartphone application (OptiBP™; test method) with arterial BP values obtained using a radial artery catheter (reference method) in order to help validate the technology. METHODS: We simultaneously measured three BP values every hour for five consecutive hours on two consecutive days using both the smartphone and arterial methods. Bland-Altman and error grid analyses were used for agreement analysis between both approaches. The performance of the smartphone application was investigated using the Association for the Advancement of Medical Instrumentation (AAMI) and the International Organization for Standardization (ISO) definitions, which require the bias ± SD between two technologies to be below 5 ± 8 mmHg. RESULTS: Among the 30 recruited patients, 22 patients had adequate OptiBP™ values and were thus analyzed. In the other 8 patients, no BP could be measured due to inadequate signals. The Bland-Altman analysis revealed a mean of the differences ± SD between both methods of 0.9 ± 7 mmHg for mean arterial pressure (MAP), 0.2 ± 14 mmHg for systolic arterial pressure (SAP), and 1.1 ± 6 mmHg for diastolic arterial pressure (DAP). Error grid analysis demonstrated that the proportions of measurement pairs in risk zones A to E were 88.8% (no risk), 10% (low risk), 1% (moderate risk), 0% (significant risk), and 0% (dangerous risk) for MAP and 88.4%, 8.6%, 3%, 0%, 0%, respectively, for SAP. CONCLUSIONS: This method comparison study revealed good agreement between BP values obtained using the OptiBP™ and those done invasively. The OptiBP™ fulfills the AAMI/ISO universal standards for MAP and DAP (but not SAP). Error grid showed that the most measurements (≥ 97%) were in risk zones A and B. TRIAL REGISTRATION: ClinicalTrials.gov registration: NCT04728477.

Accuracy of blood pressure measurement across BMI categories using the OptiBP™ mobile application.

PURPOSE: Obesity is a clear risk factor for hypertension. Blood pressure (BP) measurement in obese patients may be biased by cuff size and upper arm shape which may affect the accuracy of measurements. This study aimed to assess the accuracy of the OptiBP smartphone application for three different body mass index (BMI) categories (normal, overweight and obese). MATERIALS AND METHODS: Participants with a wide range of BP and BMI were recruited at Lausanne University Hospital's hypertension clinic in Switzerland. OptiBP estimated BP by recording an optical signal reflecting light from the participants' fingertips into a smartphone camera. Age, sex and BP distribution were collected to fulfil the AAMI/ESH/ISO universal standards. Both auscultatory BP references and OptiBP BP were measured and compared using the simultaneous opposite arms method, as described in the 81060-2:2018 ISO norm. Subgroup analyses were performed for each BMI category. RESULTS: We analyzed 414 recordings from 95 patients: 34 were overweight and 15 were obese. The OptiBP application had a performance acceptance rate of 82%. The mean and standard deviation (SD) differences between the optical BP estimations and the auscultatory reference rates (criterion 1) were respected in all subgroups: SBP mean value was 2.08 (SD 7.58); 1.32 (6.44); -2.29 (5.62) respectively in obese, overweight and normal weight subgroup. For criterion 2, which investigates the precision errors on an individual level, the threshold for systolic BP in the obese group was slightly above the requirement for this criterion. CONCLUSION: This study demonstrated that the OptiBP application is easily applicable to overweight and obese participants. Differences between the reference measure and the OptiBP estimation were within ISO limits (criterion 1). In obese participants, the SD of mean error was outside criterion 2 limits. Whether auscultatory measurement, due to arm morphology or the OptiBP is associated with increasing bias in obese still needs to be studied.

What is the context? • Hypertension and obesity have a major impact on population health and costs. • Obesity is a chronic disease characterized by abnormal or excessive fat accumulation. • Obesity, in combination with other diseases like hypertension, is a major risk factor for cardiovascular and total death. • In Europe, the obesity rate is 21.5% for men and 24.5% for women. • Hypertension, which continues to increase in the population, is a factor that can be modified when well managed. • Blood pressure measurement by the usual method may be complicated in obese patients due to fat accumulation and the shape of the arm and can lead to measurement errors. In addition, the non-invasive blood pressure measurement can be constraining and uncomfortable.What is new? • Smartphone apps are gradually appearing and allow the measurement of blood pressure without a pressure cuff using photoplethysmography. • OptiBP is a smartphone application that provides an estimate of blood pressure that has been evaluated in the general population. • The objective of this study is to assess whether OptiBP is equally effective in obese and overweight patients.What is the impact? • The use of smartphones to estimate BP in overweight and obese patients may be a solution to the known bias associated with cuff measurement. • The acquisition of more and more data with a larger number of patients will allow the continuous improvement of the application's algorithm.

Evaluation of a novel mobile phone application for blood pressure monitoring: a proof of concept study.

To provide information about the clinical relevance of blood pressure (BP) measurement differences between a new smartphone application (OptiBP™) and the reference method (automated oscillometric technique) using a noninvasive brachial cuff in patients admitted to the emergency department. We simultaneously recorded three BP measurements using both the reference method and the novel OptiBP™ (test method), except when the inter-arm difference was > 10 mmHg BP. Each OptiBP™ measurement required 1-min and the subsequent reference method values were compared to the values obtained with OptiBP™ using a Bland-Altman analysis and error grid analysis. Among the 110 patients recruited, OptiBP™ BP values could be collected on 61 patients (55%) and were included in the statistical analysis. The mean of differences (95% limits of agreement) between the reference method and the test method were - 0.1(- 22.5 to 22.4 mmHg) for systolic arterial pressure (SAP), - 0.1(- 12.9 to 12.7 mmHg) for diastolic arterial pressure (DAP) and - 0.3(- 18.1 to 17.4 mmHg) for mean arterial pressure (MAP). The proportions of measurements in risk zones A-E were 86.9%, 13.1%, 0%, 0%, and 0% for MAP and 89.3%, 10.7%, 0%, 0%, and 0% for SAP. In this pilot study conducted in stable and awake patients admitted to the emergency department, the absolute agreement between the OptiBP™ and the reference method was moderate. However, when BP measurements were made immediately after an initial calibration, error grid analysis showed that 100% of measurement differences between the OptiBP™ and reference method were categorized as no- or low-risk treatment decisions for all patients.Trial Registration: ClinicalTrials.gov Identifier: NCT04121624.

Evaluation of a new smartphone optical blood pressure application (OptiBP™) in the post-anesthesia care unit: a method comparison study against the non-invasive automatic oscillometric brachial cuff as the reference method.

We compared blood pressure (BP) values obtained with a new optical smartphone application (OptiBP™) with BP values obtained using a non-invasive automatic oscillometric brachial cuff (reference method) during the first 2 h of surveillance in a post-anesthesia care unit in patients after non-cardiac surgery. Three simultaneous BP measurements of both methods were recorded every 30 min over a 2-h period. The agreement between measurements was investigated using Bland-Altman and error grid analyses. We also evaluated the performance of the OptiBP™ using ISO81060-2:2018 standards which requires the mean of the differences ± standard deviation (SD) between both methods to be less than 5 mmHg ± 8 mmHg. Of 120 patients enrolled, 101 patients were included in the statistical analysis. The Bland-Altman analysis demonstrated a mean of the differences ± SD between the test and reference methods of + 1 mmHg ± 7 mmHg for mean arterial pressure (MAP), + 2 mmHg ± 11 mmHg for systolic arterial pressure (SAP), and + 1 mmHg ± 8 mmHg for diastolic arterial pressure (DAP). Error grid analysis showed that the proportions of measurement pairs in risk zones A to E were 90.3% (no risk), 9.7% (low risk), 0% (moderate risk), 0% (significant risk), 0% (dangerous risk) for MAP and 89.9%, 9.1%, 1%, 0%, 0% for SAP. We observed a good agreement between BP values obtained by the OptiBP™ system and BP values obtained with the reference method. The OptiBP™ system fulfilled the AAMI validation requirements for MAP and DAP and error grid analysis indicated that the vast majority of measurement pairs (≥ 99%) were in risk zones A and B.Trial Registration ClinicalTrials.gov Identifier: NCT04262323.

Pediatric Trauma: Six Years of Experience in a Swiss Trauma Center.

OBJECTIVES: The purpose of this study was to provide an internationally comparable overview of pediatric trauma of the University Hospital of Lausanne to improve the care of children. METHODS: We analyzed the data from all injured children (<16 years of age) listed in our trauma registry from 2011 to 2016. These children were admitted to the resuscitation room after prehospital triage. Our data were analyzed using descriptive statistics. RESULTS: We included 327 children. Sixty-three percent were male, and the median age was 8 years. Severe trauma (Injury Severity Score (ISS), >15) occurred in 97 children. The principal mechanisms of injury were falls (45%), traffic accidents (29%), and burns (14%). The most frequently affected areas were the head and external body regions. Intensive care admissions amounted to 27%. Twenty percent of patients underwent immediate surgery (wound care, neurosurgery, and orthopedic surgery). The overall mortality rate was 5.5%, with a median ISS of 9. The mortality of severe trauma was 17.5%, with a median ISS of 22. Half of the children died within 6 hours. The main causes of death were falls from greater than 5 m and traffic accidents as pedestrians. CONCLUSIONS: The demographics and patterns of injury in the pediatric trauma population are similar to other European pediatric trauma centers, but the mortality and the severity of injuries can vary (United Kingdom, 3.7%, median ISS of 9; Denmark, 7.3%, median ISS of 9; and Germany, 13.4%, median ISS of 25). The elevated early mortality rate suggests that improvements in prehospital care and early resuscitation could decrease mortality.

[Transforming operating rooms into an intensive care unit to manage the COVID-19 outbreak]. / Transformation du bloc opératoire en unité de soins intensifs pour gérer la pandémie de Covid-19.

This article is a descriptive analysis of the organizational steps undertaken to transform eight OR (operating rooms) of the University Hospital Lausanne CHUV into a dedicated ICU (intensive care unit) during the COVID-19 pandemic. An efficient response of our institution was mandatory to timely increase the number of ICU beds. The transformation of an entire floor of a functioning operating ward was deemed the most appropriate solution to provide rapidly a significant number of beds. The newly created ICU was the first additional ICU to open and admitted its first patient 48 hours after the beginning of the transformation.

Cet article résume les étapes organisationnelles entreprises pour transformer huit salles d'opération en une unité de soins intensifs pendant la pandémie de Covid-19. Une réponse efficace de notre institution était obligatoire pour augmenter en temps opportun le nombre de lits en soins intensifs. La transformation d'un étage entier d'un bloc opératoire fonctionnel a été jugée la solution la plus appropriée pour offrir le plus rapidement possible un nombre de lits conséquent. La nouvelle unité de soins intensifs adultes (SIA) a été la première unité de soins intensifs supplémentaire à ouvrir et a admis son premier patient 48 heures après le début des transformations.

Automated Pulse Oximeter Waveform Analysis to Track Changes in Blood Pressure During Anesthesia Induction: A Proof-of-Concept Study.

BACKGROUND: Intraoperative hypotension is associated with postoperative complications and death. Oscillometric brachial cuffs are used to measure arterial pressure (AP) in most surgical patients but may miss acute changes in AP. We hypothesized that pulse oximeter waveform analysis may help to detect changes in systolic AP (SAP) and mean AP (MAP) during anesthesia induction. METHODS: In 40 patients scheduled for an elective surgery necessitating general anesthesia and invasive AP monitoring, we assessed the performance of a pulse oximeter waveform analysis algorithm (optical blood pressure monitoring [oBPM]) to estimate SAP, MAP, and their changes during the induction of general anesthesia. Acute AP changes (>20%) in SAP and MAP assessed by the reference invasive method and by oBPM were compared using 4-quadrant and polar plots. The tracking ability of the algorithm was evaluated on changes occurring over increasingly larger time spans, from 30 seconds up to 5 minutes. The second objective of the study was to assess the ability of the oBPM algorithm to cope with the Association for the Advancement of Medical Instrumentation (AAMI) standards. The accuracy and precision of oBPM in estimating absolute SAP and MAP values compared to the invasive method was evaluated at various instants after algorithm calibration, from 30 seconds to 5 minutes. RESULTS: Rapid changes (occurring over time spans of ≤60 seconds) in SAP and MAP assessed by oBPM were strongly correlated and showed excellent concordance with changes in invasive AP (worst-case Pearson correlation of 0.94 [0.88, 0.97] [95% confidence interval], concordance rate of 100% [100%, 100%], and angular concordance rate at ±30° of 100% [100%, 100%]). The trending ability tended to decrease progressively as the time span over which the changes occurred increased, reaching 0.89 (0.85, 0.91) (Pearson correlation), 97% (95%, 100%) (concordance rate), and 90% (85%, 94%) (angular concordance rate) in the worst case. Regarding accuracy and precision, oBPM-derived SAP values were shown to comply with AAMI criteria up to 2 minutes after calibration, whereas oBPM-derived MAP values were shown to comply with criteria at all times. CONCLUSIONS: Pulse oximeter waveform analysis was useful to track rapid changes in SAP and MAP during anesthesia induction. A good agreement with reference invasive measurements was observed for MAP up to at least 5 minutes after initial calibration. In the future, this method could be used to track changes in AP between intermittent oscillometric measurements and to automatically trigger brachial cuff inflation when a significant change in AP is detected.

[Out-of-hospital tracheal intubation and alternatives in the prehospital setting]. / Intubation trachéale et alternatives en préhospitalier.

The purpose of this article is to review the main airway devices available to the emergency physician in a prehospital setting. Since the risk of difficult intubation is increased under pre-hospital conditions; the emergency physician should be aware of alternatives to direct tracheal intubation such as supraglottic devices, video laryngoscopes and cricothyroidotomy. These different techniques and devices must be integrated into a strategy for the management of the upper airway. We propose a prehospital airways algorithm adapted from the Latin Airway Foundation (FLAVA).

L'objectif de cet article est de passer en revue les principaux dispositifs de gestion des voies aériennes à disposition du médecin d'urgence. Le risque d'intubation difficile étant majoré dans les conditions d'intervention préhospitalière, le médecin d'urgence doit connaître les alternatives à l'intubation trachéale par laryngoscopie directe telles que les dispositifs supraglottiques, les vidéolaryngoscopes et la cricothyroïdotomie. Ces différentes techniques et dispositifs doivent être intégrés dans une stratégie de gestion des voies aériennes supérieures. Nous proposons un algorithme adapté pour le préhospitalier inspiré de celui de la Fondation latine des voies aériennes (FLAVA).

Development and Initial Evaluation of a Novel, Ultraportable, Virtual Reality Bronchoscopy Simulator: The Computer Airway Simulation System.

BACKGROUND: Virtual reality (VR) simulation is an effective and safe method of teaching bronchoscopic skills. Few VR bronchoscopy simulators exist; all are expensive. The present study aimed to describe the design, development, and evaluation of a new, affordable, VR bronchoscopy simulator. METHODS: Anesthesiologists and engineers collaborated to design and develop the Computer Airway Simulation System (CASS), an iPad-based, high-fidelity, VR bronchoscopy simulator. We describe hardware and software development, as well as the technical and teaching features of the CASS. Twenty-two senior anesthesiologists evaluated various aspects of the simulator (using a 5-point Likert scale) to assess its face validity. RESULTS: Anesthesiologists performed a simulated bronchoscopy (mouth to carina) with a median (range) procedural time of 66 seconds (30-96). The simulator's ease of use was rated 4.3 ± 0.8 and the bronchoscope proxy's handling 4.0 ± 0.7. Criticisms included that excessive system reactivity created handling difficulties. Anatomical accuracy, 3-dimensional bronchial segmentation, and mucosal texture were judged to be very realistic. The simulator's usefulness for teaching and its educational value were highly rated (4.9 ± 0.3 and 4.8 ± 0.4, respectively). CONCLUSIONS: We describe the design, development, and initial evaluation of the CASS-a new, ultraportable, affordable, VR bronchoscopy simulator. The simulator's face validity was supported by excellent assessments from senior anesthesiologists with regard to anatomical realism, quality of graphics, and handling performance, even though some future refinements are required. All the practitioners agreed on the significant educational potential of the CASS.

The role of tracheal tube introducers and stylets in current airway management.

Tracheal tube introducers and stylets are highly successful devices for the management of various airway scenarios. Their first-line use is advocated in many difficult airway algorithms. Although they have been used for decades, the shape and design of introducers and stylets as well as their patterns of use are constantly evolving. Our purpose is to provide the clinician with an update on these different devices. We performed a systematic literature search from 2005 until May 2015, without language restrictions. The two authors independently retrieved all studies with the keywords "bougie", "gum elastic bougie", "stylet", "airway management", "tracheal tube introducer" and "extubation catheter". Our search did yield mostly observational and retrospective studies with small case numbers. The data was synthesized into a narrative review to provide the clinician with an update on the characteristics, indications and techniques of use as well as the dangers of different intubation aids. Today, numerous tracheal tube introducers and stylets exist with different indications, ranging from general to specific situations. Anesthetists should be familiar with the different devices, their characteristics and indications in order to use the right device at the right time in the right way.

Accuracy of brain multimodal monitoring to detect cerebral hypoperfusion after traumatic brain injury*.

OBJECTIVE: To examine the accuracy of brain multimodal monitoring-consisting of intracranial pressure, brain tissue PO2, and cerebral microdialysis--in detecting cerebral hypoperfusion in patients with severe traumatic brain injury. DESIGN: Prospective single-center study. PATIENTS: Patients with severe traumatic brain injury. SETTING: Medico-surgical ICU, university hospital. INTERVENTION: Intracranial pressure, brain tissue PO2, and cerebral microdialysis monitoring (right frontal lobe, apparently normal tissue) combined with cerebral blood flow measurements using perfusion CT. MEASUREMENTS AND MAIN RESULTS: Cerebral blood flow was measured using perfusion CT in tissue area around intracranial monitoring (regional cerebral blood flow) and in bilateral supra-ventricular brain areas (global cerebral blood flow) and was matched to cerebral physiologic variables. The accuracy of intracranial monitoring to predict cerebral hypoperfusion (defined as an oligemic regional cerebral blood flow < 35 mL/100 g/min) was examined using area under the receiver-operating characteristic curves. Thirty perfusion CT scans (median, 27 hr [interquartile range, 20-45] after traumatic brain injury) were performed on 27 patients (age, 39 yr [24-54 yr]; Glasgow Coma Scale, 7 [6-8]; 24/27 [89%] with diffuse injury). Regional cerebral blood flow correlated significantly with global cerebral blood flow (Pearson r = 0.70, p < 0.01). Compared with normal regional cerebral blood flow (n = 16), low regional cerebral blood flow (n = 14) measurements had a higher proportion of samples with intracranial pressure more than 20 mm Hg (13% vs 30%), brain tissue PO2 less than 20 mm Hg (9% vs 20%), cerebral microdialysis glucose less than 1 mmol/L (22% vs 57%), and lactate/pyruvate ratio more than 40 (4% vs 14%; all p < 0.05). Compared with intracranial pressure monitoring alone (area under the receiver-operating characteristic curve, 0.74 [95% CI, 0.61-0.87]), monitoring intracranial pressure + brain tissue PO2 (area under the receiver-operating characteristic curve, 0.84 [0.74-0.93]) or intracranial pressure + brain tissue PO2+ cerebral microdialysis (area under the receiver-operating characteristic curve, 0.88 [0.79-0.96]) was significantly more accurate in predicting low regional cerebral blood flow (both p < 0.05). CONCLUSION: Brain multimodal monitoring-including intracranial pressure, brain tissue PO2, and cerebral microdialysis--is more accurate than intracranial pressure monitoring alone in detecting cerebral hypoperfusion at the bedside in patients with severe traumatic brain injury and predominantly diffuse injury.

Validation of rotational thromboelastometry during cardiopulmonary bypass: A prospective, observational in-vivo study.

BACKGROUND: Rotational thromboelastometry (ROTEM) is a whole blood point-of-test used to assess the patient's coagulation status. Three of the available ROTEM tests are EXTEM, INTEM and HEPTEM. In the latter, heparinase added to the INTEM reagent inactivates heparin to reveal residual heparin effect. Performing ROTEM analysis during cardiopulmonary bypass (CPB) might allow the anaesthesiologist to anticipate the need for blood products. OBJECTIVE: The goal of this study was to validate ROTEM analysis in the presence of very high heparin concentrations during CPB. DESIGN: Prospective, observational trial. SETTING: Single University Hospital. PARTICIPANTS: Twenty patients undergoing coronary artery bypass grafting. MAIN OUTCOME MEASURE: ROTEM analysis was performed before heparin administration (T0), 10 min after heparin (T1), at the end of CPB (T2) and 10 min after protamine (T3). The following tests were performed: EXTEM, INTEM, and HEPTEM. Heparin concentrations were measured at T1 and at the end of bypass (T2). RESULTS: At T1, EXTEM differed from baseline for coagulation time: +26.7 s (18.4 to 34.9, P < 0.0001), α: -3° (1.0 to 5.4, P = 0.006) and A10: -4.4 mm (2.3 to 6.5, P = 0.0004). INTEM at T0 was different from HEPTEM at T1 for coagulation time: + 47 s (34.3 to 59.6, P > 0.0001), A10: -2.3 mm (0.5 to 4.0, P = 0.01) and α -2° (1.0 to 3.0; P = 0.0007). At T2, all parameters in EXTEM and HEPTEM related to fibrin-platelet interaction deteriorated significantly compared to T1. At T3, EXTEM and INTEM were comparable to EXTEM and HEPTEM at T2. CONCLUSION: HEPTEM and EXTEM measurements are valid in the presence of very high heparin concentrations and can be performed before protamine administration in patients undergoing cardiac surgery with CPB. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01455454.

Innovations to Improve Lung Isolation Training for Thoracic Anesthesia: A Narrative Review.

A double-lumen tube or bronchial blocker positioning using flexible bronchoscopy for lung isolation and one-lung ventilation requires specific technical competencies. Training to acquire and retain such skills remains a challenge in thoracic anesthesia. Recent technological and innovative developments in the field of simulation have opened up exciting new horizons and possibilities. In this narrative review, we examine the latest development of existing training modalities while investigating, in particular, the use of emergent techniques such as virtual reality bronchoscopy simulation, virtual airway endoscopy, or the preoperative 3D printing of airways. The goal of this article is, therefore, to summarize the role of existing and future applications of training models/simulators and virtual reality simulators for training flexible bronchoscopy and lung isolation for thoracic anesthesia.

Smartphone-Based versus Non-Invasive Automatic Oscillometric Brachial Cuff Blood Pressure Measurements: A Prospective Method Comparison Volunteer Study.

Introduction: Mobile health diagnostics have demonstrated effectiveness in detecting and managing chronic diseases. This method comparison study aims to assess the accuracy and precision of the previously evaluated OptiBP™ technology over a four-week study period. This device uses optical signals recorded by placing a patient's fingertip on a smartphone's camera to estimate blood pressure (BP). Methods: In adult participants without cardiac arrhythmias and minimal interarm blood pressure difference (systolic arterial pressure (SAP) < 15 mmHg or diastolic arterial pressure (DAP) < 10 mmHg), three pairs of 30 s BP measurements with the OptiBP™ (test method) were simultaneously compared using three pairs of measurements with the non-invasive oscillometric brachial cuff (reference method) on the opposite arm over a period of four consecutive weeks at a rate of two measurements per week (one in the morning and one in the afternoon). The agreement of BP values between the two technologies was analyzed using Bland-Altman and error grid analyses. The performance of the smartphone application was investigated using the International Organization for Standardization (ISO) definitions, which require the bias ± standard deviation (SD) between two technologies to be lower than 5 ± 8 mmHg. Results: Among the 65 eligible volunteers, 53 participants had adequate OptiBP™ BP values. In 12 patients, no OptiBP™ BP could be measured due to inadequate signals. Only nine participants had known chronic arterial hypertension and 76% of those patients were treated. The mean bias ± SD between both technologies was -1.4 mmHg ± 10.1 mmHg for systolic arterial pressure (SAP), 0.2 mmHg ± 6.5 mmHg for diastolic arterial pressure (DAP) and -0.5 mmHg ± 6.9 mmHg for mean arterial pressure (MAP). Error grid analyses indicated that 100% of the pairs of BP measurements were located in zones A (no risk) and B (low risk). Conclusions: In a cohort of volunteers, we observed an acceptable agreement between BP values obtained with the OptiBPTM and those obtained with the reference method over a four-week period. The OptiBPTM fulfills the ISO standards for MAP and DAP (but not SAP). The error grid analyses showed that 100% measurements were located in risk zones A and B. Despite the need for some technological improvements, this application may become an important tool to measure BP in the future.

Pulse contour techniques for perioperative hemodynamic monitoring: A nationwide carbon footprint and cost estimation.

BACKGROUND: The question of environmentally sustainable perioperative medicine represents a new challenge in an era of cost constraints and climate crisis. The French Society of Anaesthesia and Intensive Care (SFAR) recommends stroke volume optimization in high-risk surgical patients. Pulse contour techniques have become increasingly popular for stroke volume monitoring during surgery. Some require the use of specific disposable pressure transducers (DPTs), whereas others can be used with standard DPTs. OBJECTIVE: Quantify and compare the carbon footprint and cost of pulse contour techniques using specific and standard DPTs on a yearly basis and at a national level. METHODS: We estimated the number of high-risk surgical patients monitored every year in France with a pulse contour technique, and the plastic waste, carbon footprint and cost associated with the use of specific and standard DPTs. MAIN FINDINGS: When compared to pulse contour techniques working with a standard DPT, techniques requiring a specific DPT are responsible for an increase in carbon dioxide emission estimated at 65-83 tons/yr and for additional hospital cost estimated at €67 million/yr. If, as recommended by the SFAR, all high-risk surgical patients were monitored, the difference would reach 179-227 tons/yr for the environmental impact and €187 million/yr for the economic impact. CONCLUSION: From an environmental and economic standpoint, pulse contour techniques working with standard DPTs should be recommended for the perioperative hemodynamic monitoring of high-risk surgical patients.