Real-world data describing contemporary hyperbaric oxygen therapy (HBOT) practice in Italy are limited. This study aimed to describe current clinical indications and therapeutic modalities of HBOT at the national level. We conducted a multicentre, prospective, observational national study, promoted by Italian Society of Anesthesia Analgesia, Resuscitation and Intensive Care (SIAARTI). We included consecutive patients who underwent HBOT in 10 study centres within a period of 12 weeks, for any treatment indication. The primary outcome of the study was the proportion of treatments by clinical indication and urgency of treatment. Overall, 327 patients were included across 10 centres, of which 73.7

Clinical effectiveness of high-flow nasal therapy (HFNT) over conventional oxygen therapy (COT) in patients with mild COVID-19-related acute hypoxaemic respiratory failure (AHRF) remains uncertain. The COVID-HIGH trial did not demonstrate statistically significant benefits of HFNT over COT. However, the trial was slightly underpowered, and the event rate lower-than-expected. Bayesian methods provide deeper insight by incorporating prior knowledge and quantifying uncertainty intuitively. This analysis aimed to quantify the probability of benefit or harm associated with HFNT, adopting a Bayesian approach. We performed a Bayesian reanalysis of the COVID-HIGH trial (NCT, which randomised 364 patients with PaO₂/FiO₂ between 200–300 mmHg to receive HFNT or COT. The primary outcome was escalation of respiratory support (continuous positive airway pressure, noninvasive ventilation or invasive mechanical ventilation) within 28 days. A key secondary outcome was clinical recovery at day 14. Bayesian logistic models with noninformative and informative priors were used to estimate the posterior probability of treatment effects. Escalation of respiratory support occurred in 23.6

The optimal mean arterial pressure (MAP) target in high-risk hypertensive patients undergoing major abdominal surgery remains unclear. The HISTAP trial evaluated whether targeting an intraoperative MAP ≥ 80 compared with ≥ 65 mmHg reduces postoperative organ dysfunction and 30-day mortality, in this population. HISTAP was a multicenter, randomized trial conducted at 18 Italian centers between March 2023 and April 2025. The study included patients aged ≥ 60 years with chronic hypertension requiring home therapy, undergoing elective major abdominal surgery and having at least one additional high-risk criterion. The intraoperative MAP was targeted to ≥ 80 mmHg (Treatment group) or ≥ 65 mmHg (Control group). The primary outcome was a composite endpoint including postoperative mortality and at least one major organ dysfunction. Of 636 randomized patients, 6 were excluded since surgery was canceled after randomization, 630 completed the trial and were included in the intention-to-treat analysis (median age, 74 years [IQR, 69–79]). Mean intraoperative MAP was 77 ± 7 mmHg in the Control group and 88 ± 9 mmHg in the Treatment group. The primary composite outcome occurred in 48.9

Objective The impact of left ventricular (LV) systolic dysfunction on weaning failure is unclear. Design Updated meta-analysis assessing the association between LV ejection fraction (LVEF) and weaning failure. Setting A systematic search of MEDLINE and EMBASE for prospective studies reporting weaning according to echocardiographic data measured before starting a spontaneous breathing trial (SBT). Patients or participants Studies included in the meta-analysis that reported on weaning and echocardiographic data. Main variables of interest LVEF, E/e’ ratio, E velocity, deceleration time of the E wave, and e’ velocity. Results Three studies were added in this update (n = 14, sample 20–30% larger). Lower LVEF (n = 12) was associated with weaning failure: MD: −4.71 95%CI [−9.18, −0.23]; p = 0.04, I2 = 90%, low certainty of evidence), without subgroups difference according to SBT type or LVEF mean values. Trial sequential analysis showed that results were not robust (information size n = 745/1378). E/e’ ratio (MD: 1.90, 95%CI [0.48,3.32]; p = 0.009, I2 = 84%), E velocity (MD: 8.32, 95%CI [2.59,14.05]; p = 0.004, I2 = 54%) and shorter deceleration time of the E wave (MD: −12.01, 95%CI [−21.13, −2.89]; p = 0.01, I2 = 0%) were associated with weaning failure, whilst e’ velocity was not (MD: -0.59, 95%CI [−1.51,0.32]; p = 0.20, I2 = 64%). Conclusions An association of weaning failure with poorer LV systolic function (LVEF), not detected by the previous meta-analysis, was found. However, such association is highly fragile and with a mean difference below 5%, which seems not clinically relevant. Higher E/e’ ratio and other diastolic parameters confirmed their association with weaning failure, whilst e’ did not.

Introduction Flexible bronchoscopy (FB) is widely used for diagnostic and therapeutic procedures in pulmonary medicine. However, FB can cause respiratory and haemodynamic complications, especially in patients with pre-existing lung and/or cardiovascular comorbidities. Despite the range of oxygenation and ventilatory approaches available to prevent these risks, evidence regarding their real-world application and clinical impact is limited. The OxyFOB study aims to assess the prevalence and outcomes of various oxygenation and ventilatory support strategies used during FB across Europe.Methods and analysis The OxyFOB study is a large, prospective, international, observational cohort study which aims to involve over 10 000 FB procedures across European centres. Eligible participants include all adults undergoing FB for diagnostic, therapeutic or procedural indications. Data are collected via a standardised electronic case report form and encompass demographic information, procedural details and clinical outcomes. The primary endpoint is the prevalence of oxygenation and ventilatory support strategies: conventional oxygen therapy, high-flow oxygen therapy, continuous positive airway pressure, non-invasive ventilation and invasive mechanical ventilation. Secondary outcomes include periprocedural respiratory and haemodynamic events, patient comfort, dyspnoea and postprocedural complications. Statistical analyses include descriptive statistics, subgroup comparisons and multivariate logistic regression.Ethics and dissemination The study has received ethical approval from the coordinating centre (protocol n. 22/2022 on the 20 January 2022, by the ‘Comitato Etico Sezione Area Centro - Regione Calabria’) and all participating sites. Informed consent is given from all patients or their legal representatives. Findings will be disseminated through peer-reviewed publications and presentations at international meetings. Data will be managed and made available on reasonable request to support further research.Trial registration number ClinicalTrials.gov ID: NCT05681962. Registered January 2023.

BACKGROUND:High-flow nasal therapy (HFNT) is a widely used non-invasive respiratory support technique, but data on its clinical application remain limited. This study aimed to assess clinicians' self-reported practices, perceptions and barriers regarding HFNT use in acute and chronic respiratory failure. METHODS:A cross-sectional web-based survey was disseminated among members of the European Respiratory Society's respiratory intensive care, rehabilitation and chronic care, and allied respiratory professionals assemblies from September to November 2023. Descriptive analysis was performed, with results presented as frequencies and percentages. RESULTS:A total of 1176 clinicians from 104 countries participated, primarily pulmonologists (78.3%) and respiratory therapists (9.7%). HFNT was most commonly used for de novo acute respiratory failure (56.2%) and interstitial lung disease exacerbations (56.3%), with lower utilisation for chronic obstructive pulmonary disease with hypercapnia (47.4%) and trauma/atelectasis (41.5%). Despite guideline recommendations, 67% of respondents initiated HFNT only after conventional oxygen therapy failure. HFNT was also frequently used for symptom relief in palliative care, despite limited supporting evidence. Respiratory distress was the primary clinical trigger for HFNT initiation, while the ROX (Respiratory Rate-Oxygenation) index was rarely used to guide escalation of care (32%). Barriers to HFNT adoption included equipment costs (23%), lack of funding (22%) and limited clinician knowledge (18%). HFNT use increased during the COVID-19 pandemic (84%), but long-term application for chronic respiratory failure remained rare (16%). CONCLUSIONS:This survey highlights significant variability in HFNT practices and a disconnect between guidelines and real-world implementation. Addressing financial and educational barriers may improve adherence to evidence-based recommendations.

Evaluating fluid responsiveness (FR) is crucial in managing critically ill patients. Measurement of respiratory variations of blood flow (Vpeak) is physiologically sound, but blood flow sampling through the aortic valve (AV-Vpeak) is not always feasible. We assessed the feasibility of suprasternal Vpeak (SS-Vpeak), at ascending or descending aorta level, as alternative to AV-Vpeak. Observational prospective study in spontaneously breathing healthy volunteers. We report the overall feasibility of AV- and SS-Vpeak, and calculated their interchangeability, the mean bias with limits of agreement (LoA) and percentage error (PE). We defined FR as a 10

BACKGROUND:Intravenous administration of paracetamol to critically ill patients may have negative hemodynamic effects. However, such effects have not been adequately quantified. METHODS:We conducted a systematic review and meta-analysis of observational studies (published in English language in PubMed and/or EMBASE) conducted on intensive care unit (ICU) patients, reporting hemodynamic changes within 30 min of intravenous paracetamol administration for fever and/or analgesia. The primary outcome was the mean difference (MD) with 95% confidence interval [95%CI] in mean arterial pressure (MAP). Secondary outcomes were systolic and diastolic arterial pressure (SAP and DAP), heart rate (HR), and incidence of hypotension. Trial sequential analysis (TSA) was conducted to ascertain the robustness of findings. RESULTS:Eight studies were included. We observed significant reduction after paracetamol of MAP (5 studies, MD: -6.75 mmHg [-10.68; -2.82]; p = 0.0008; I2 = 74%), SAP (5 studies, MD: -11.55 mmHg [-20.55; -2.55]; p = 0.01; I2 = 78%) and DAP (5 studies, MD: -5.29 mmHg [-8.53; -2.05]; p = 0.001; I2 = 42%). No effects were seen for HR (4 studies, MD: -3.08 bpm [-7.09;0.93]; p = 0.13; I2 = 0%). Subgroup analyses were hampered by the small number of studies. MAP reduction appeared consistent when paracetamol was administered for fever. TSAs showed that results on MAP and DAP were robust; SAP and HR were not. The grade of evidence was very low. The occurrence of hypotension after intravenous paracetamol was 45.5% (n = 143/314, 4 studies). CONCLUSIONS:Hypotension after intravenous paracetamol is frequent in the ICU, with significant reduction in MAP, SAP, and DAP but no effects on HR. Effects seem more pronounced in patients with fever. More advanced hemodynamic studies are needed to understand the mechanisms of paracetamol-induced hypotension. REGISTRATION:PROSPERO (CRD number 42024574919).

Patients with bronchiectasis treated with long-term high-flow nasal therapy showed a significant improvement in mucus plug score https://bit.ly/3NV39zI.

Millions of critically ill patients are discharged from intensive care units (ICUs) every year. These ICU survivors may suffer from a condition known as post-intensive care syndrome (PICS) which includes a wide range of cognitive, psychological, and physical impairments. This article will provide an extensive review of PICS. ICU survivors may experience cognitive deficits in memory and attention, with a slow-down of mental processing and problem-solving. From psychological perspectives, depression, anxiety, and post-traumatic stress disorder are the most common issues suffered after ICU discharge. These psycho-cognitive impairments might be coupled with ICU-acquired weakness (polyneuropathy and/or myopathy), further reducing the quality of life, the ability to return to work, and other daily activities. The burden of ICU survivors extends to families too, leading to the so-called PICS-family (or PICS-F), which entails the psychological impairments suffered by the family and, in particular, by the caregiver of the ICU survivor. The development of PICS (and PICS-F) is likely multifactorial, and both patient- and ICU-related factors may influence it. Whilst the prevention of PICS is complex, it is important to identify the patients at higher risk of PICS, and clinicians should be aware of the tools available for diagnosis. Stakeholders should implement strategies to achieve PICS prevention and to support its effective treatment during the recovery phase with dedicated pathways and supporting care.

The Inferior Vena Cava (IVC) is commonly utilized to evaluate fluid status in the Intensive Care Unit (ICU),with more recent emphasis on the study of venous congestion. It is predominantly measured via subcostal approach (SC) or trans-hepatic (TH) views, and automated border tracking (ABT) software has been introduced to facilitate its assessment. Prospective observational study on patients ventilated in pressure support ventilation (PSV) with 2 × 2 factorial design. Primary outcome was to evaluate interchangeability of measurements of the IVC and the distensibility index (DI) obtained using both M-mode and ABT, across both SC and TH. Statistical analyses comprised Bland–Altman assessments for mean bias, limits of agreement (LoA), and the Spearman correlation coefficients. IVC visualization was 100% successful via SC, while TH view was unattainable in 17.4% of cases. As compared to the M-mode, the IVC-DI obtained through ABT approach showed divergences in both SC (mean bias 5.9%, LoA -18.4% to 30.2%, ICC = 0.52) and TH window (mean bias 6.2%, LoA -8.0% to 20.4%, ICC = 0.67). When comparing the IVC-DI measures obtained in the two anatomical sites, accuracy improved with a mean bias of 1.9% (M-mode) and 1.1% (ABT), but LoA remained wide (M-mode: -13.7% to 17.5%; AI: -19.6% to 21.9%). Correlation was generally suboptimal (r = 0.43 to 0.60). In PSV ventilated patients, we found that IVC-DI calculated with M-mode is not interchangeable with ABT measurements. Moreover, the IVC-DI gathered from SC or TH view produces not comparable results, mainly in terms of precision.

Background/Objectives: Neuronal Ceroid Lipofuscinosis type 2 is a rare pathology affecting mainly the central nervous system (CNS) and retina, and is caused by variants in the gene encoding the lysosomal enzyme tripeptidyl peptidase 1. Therapy with enzyme replacement through the brain infusion of the orphan drug cerliponase alfa, a recombinant human tripeptidyl peptidase 1 enzyme replacement therapy delivered via intracerebroventricular infusion, has been approved for Neuronal Ceroid Lipofuscinosis type 2 disease. The safety profile of cerliponase alfa has been established based on pre-authorization studies; currently, no post-marketing investigation has been performed to confirm it. Here, a descriptive analysis of real-world spontaneous reporting data of suspected adverse reactions (SARs) to cerliponase alfa in the EudraVigilance database was performed to compile clear information on the safety profile. Methods: Suspected adverse reactions to cerliponase alfa reported in the data system EudraVigilance were analyzed for age, sex of the patient, adverse reactions, and the indication for use. Results: Cases with suspected adverse reactions to cerliponase alfa were found to be more frequent in female patients (58.1%) and in children aged 3–11 years. The most common adverse reactions were, in decreasing order, fever/pyrexia, device-related infection, vomiting, seizures/convulsions, pleocytosis, irritability, ventriculitis, and respiratory disorders. Conclusions: The results confirm the safety profile of cerliponase alfa established with pre-registration clinical studies but suggest the need for further studies to investigate the occurrence of adverse reactions, as possible predictive prognostic markers, in more depth.

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.

BACKGROUND:Qualitative data on the opinions of anaesthesiologists regarding the impact of peri-operative night-time working conditions on patient safety are lacking.OBJECTIVES:This study aimed to achieve in-depth understanding of anaesthesiologists' perceptions regarding the impact of night-time working conditions on peri-operative patient safety and actions that may be undertaken to mitigate perceived risks.DESIGN:Qualitative analysis of responses to two open-ended questions.SETTING:Online platform questionnaire promoted by the European Society of Anaesthesiology and Intensive Care (ESAIC).PARTICIPANTS:The survey sample consisted of an international cohort of anaesthesiologists.MAIN OUTCOME MEASURES:We identified and classified recurrent themes in the responses to questions addressing perceptions regarding (Q1) peri-operative night-time working conditions, which may affect patient safety and (Q2) potential solutions.RESULTS:We analysed 2112 and 2113 responses to Q1 and Q2, respectively. The most frequently reported themes in relation to Q1 were a perceived reduction in professional performance accompanied by concerns regarding the possible consequences of work with fatigue (27%), and poor working conditions at night-time (35%). The most frequently proposed solutions in response to Q2 were a reduction of working hours and avoidance of 24-h shifts (21%), an increase in human resources (14%) and performance of only urgent or emergency surgeries at night (14%).CONCLUSION:Overall, the surveyed anaesthesiologists believe that workload-to-staff imbalance and excessive working hours were potential bases for increased peri-operative risk for their patients, partly because of fatigue-related medical errors during night-time work. The performance of nonemergency elective surgical cases at night and lack of facilities were among the reported issues and potential targets for improvement measures. Further studies should investigate whether countermeasures can improve patient safety as well as the quality of life of anaesthesia professionals. Regulations to improve homogeneity, safety, and quality of anaesthesia practice at night seem to be urgently needed.

ABSTRACTBackgroundBiological therapies, such as mepolizumab, have transformed the treatment of severe eosinophilic asthma. While mepolizumab’s short-term effectiveness is established, there is limited evidence on its ability to achieve long-term clinical remission.ObjectiveTo evaluate the long-term effectiveness and safety of mepolizumab, explore its potential to induce clinical and sustained remission, and identify baseline factors associated with the likelihood of achieving remission over 24 months.MethodsThe REMI-M is a retrospective, real-world, multicenter study that analyzed 303 severe eosinophilic asthma patients who received mepolizumab. Clinical, demographic, and safety data were collected at baseline, 3, 6, 12, and 24 months. The most commonly used definitions of clinical remission, which included no exacerbations, no oral corticosteroids (OCS) use, and good asthma control with or without assessment of lung function parameters, were adopted. Sustained remission was defined as reaching clinical remission at 12 months and maintaining it until the end of the 24-month period.ResultsClinical remission rates ranged from 28.6% to 43.2% after 12 months and from 26.8% to 52.9% after 24 months, based on the different remission definitions. The proportion of patients achieving sustained remission varied between 14.6% to 29%. Factors associated with the likelihood of achieving clinical remission included the presence of aspirin-exacerbated respiratory disease, better lung function, male sex, absence of anxiety/depression, gastro-esophageal reflux disease, bronchiectasis, and reduced OCS consumption. Adverse events were infrequent.ConclusionsThis study demonstrates the real-world effectiveness of mepolizumab in achieving clinical remission and sustained remission in severe eosinophilic asthma over 24 months. The identification of distinct factors associated with the likelihood of achieving clinical remission emphasizes the importance of comprehensive management of comorbidities and timely identification of patients who may benefit from biologics.HIGHLIGHTS BOXWhat is already known about this topic?Mepolizumab, an anti-IL-5 monoclonal antibody, has been shown to induce clinical remission after 12 months of treatment. However, long-term evidence remains limited.What does this article add to our knowledge?The REMI-M study investigated the effectiveness of mepolizumab in achieving clinical and sustained remission over 24 months.How does this study impact current management guidelines?Mepolizumab can elicit long-term clinical and sustained remission in a conspicuous proportion of patients with severe eosinophilic asthma, supporting its role as a possible disease-modifying agent. Management of comorbidities and timely identification of patients who may benefit from biological treatment are crucial for optimizing long-term outcomes.

BACKGROUND:Traditionally, Venturi-based flow generators have been preferred over mechanical ventilators to provide continuous positive airway pressure (CPAP) through the helmet (h-CPAP). Recently, modern turbine-driven ventilators (TDVs) showed to be safe and effective in delivering h-CPAP. We aimed to compare the pressure stability during h-CPAP delivered by Venturi devices and TDVs and assess the impact of High Efficiency Particulate Air (HEPA) filters on their performance. METHODS:We performed a bench study using an artificial lung simulator set in a restrictive respiratory condition, simulating two different levels of patient effort (high and low) with and without the interposition of the HEPA filter. We calculated the average of minimal (Pmin), maximal (Pmax) and mean (Pmean) airway pressure and the time product measured on the airway pressure curve (PTPinsp). We defined the pressure swing (Pswing) as Pmax - Pmin and pressure drop (Pdrop) as End Expiratory Pressure - Pmin. RESULTS:Pswing across CPAP levels varied widely among all the tested devices. During "low effort", no difference in Pswing and Pdrop was found between Venturi devices and TDVs; during high effort, Pswing (p<0.001) and Pdrop (p<0.001) were significantly higher in TDVs compared to Venturi devices, but the PTPinsp was lower (1.50 SD 0.54 vs 1.67 SD 0.55, p<0.001). HEPA filter addition almost doubled Pswing and PTPinsp (p<0.001) but left unaltered the differences among Venturi and TDVs systems in favor of the latter (p<0.001). CONCLUSIONS:TDVs performed better than Venturi systems in delivering a stable positive pressure level during h-CPAP in a bench setting.

OBJECTIVE:Wide variations exist in the use of pulmonary artery catheters (PACs) and echocardiography in the field of cardiac surgery. DESIGN:A national survey promoted by the Italian Association of Cardio-Thoracic Anesthesiologists and Intensive Care was conducted. SETTING:The study occurred in Italian cardiac surgery centers (n = 71). PARTICIPANTS:Anesthesiologists-intensivists were enrolled. INTERVENTIONS:Anonymous questionnaires were used to investigate the use of PACs and echocardiography in the operating room (OR) and intensive care unit (ICU). MEASUREMENTS AND MAIN RESULTS:A total of 257 respondents (32.2% response rate) from 59 centers (83.1% response rate) participated. Use of PACs seems less common in ORs (median insertion in 20% [5-70] of patients), with slightly higher use in ICUs; in about half of cases, it was the continuous cardiac output monitoring system of choice. Almost two-thirds of respondents recently inserted at least one PAC within a few hours of ICU admission, despite its need being largely preoperatively predictable. Protocols regulating PAC insertion were reported by 25.3% and 28% of respondents (OR and ICU, respectively). Transesophageal echocardiography (TEE) was performed intraoperatively in >75% of patients by 86.4% of respondents; only 23.7% stated that intraoperative TEE relied on anesthesiologists. Tissue Doppler and/or 3D imaging were widely available (87.4% and 82%, respectively), but only 37.8% and 24.3% of respondents self-declared skills in these modalities, respectively; 77.1% of respondents had no echocardiography certification, nor were pursuing certification (various reasons); 40.9% had not attended recent echocardiography courses. Lower PAC use was associated with university hospitals (OR: p = 0.014, ICU: p = 0.032) and with lower interventions/year (OR: p = 0.023). Higher independence in performing TEE was reported in university hospitals (OR: p < 0.001; ICU: p = 0.006), centers with higher interventions/year (OR: p = 0.019), and by respondents with less experience in cardiology (ICU: p = 0.046). CONCLUSION:Variability in the use of PACs and echocardiography was found. Protocols regulating the use of PACs seem infrequent. University centers use PACs less and have greater skills in TEE. Training and certifications in echocardiography should be encouraged.

Background Capillary Refill Time (CRT) is a marker of peripheral perfusion usually performed at fingertip; however, its evaluation at other sites/position may be advantageous. Moreover, arm position during CRT assessment has not been fully standardized. Methods We performed a pilot prospective observational study in 82 healthy volunteers. CRT was assessed: a) in standard position with participants in semi-recumbent position; b) at 30° forearm elevation, c and d) at earlobe site in semi-recumbent and supine position. Bland–Altman analysis was performed to calculate bias and limits of agreement (LoA). Correlation was investigated with Pearson test. Results Standard finger CRT values (1.04 s [0.80;1.39]) were similar to the earlobe semi-recumbent ones (1.10 s [0.90;1.26]; p = 0.52), with Bias 0.02 ± 0.18 s (LoA -0.33;0.37); correlation was weak but significant ( r = 0.28 [0.7;0.47]; p = 0.01). Conversely, standard finger CRT was significantly longer than earlobe supine CRT (0.88 s [0.75;1.06]; p < 0.001) with Bias 0.22 ± 0.4 s (LoA -0.56;1.0), and no correlation ( r = 0,12 [-0,09;0,33]; p = 0.27]. As compared with standard finger CRT, measurement with 30° forearm elevation was significantly longer (1.17 s [0.93;1.41] p = 0.03), with Bias -0.07 ± 0.3 s (LoA -0.61;0.47) and with a significant correlation of moderate degree ( r = 0.67 [0.53;0.77]; p < 0.001). Conclusions In healthy volunteers, the elevation of the forearm significantly prolongs CRT values. CRT measured at the earlobe in semi-recumbent position may represent a valid surrogate when access to the finger is not feasible, whilst earlobe CRT measured in supine position yields different results. Research is needed in critically ill patients to evaluate accuracy and precision at different sites/positions.

Abstract Purpose Assessment of the inferior vena cava (IVC) respiratory variation may be clinically useful for the estimation of fluid-responsiveness and venous congestion; however, imaging from subcostal (SC, sagittal) region is not always feasible. It is unclear if coronal trans-hepatic (TH) IVC imaging provides interchangeable results. The use of artificial intelligence (AI) with automated border tracking may be helpful as part of point-of-care ultrasound but it needs validation. Methods Prospective observational study conducted in spontaneously breathing healthy volunteers with assessment of IVC collapsibility (IVCc) in SC and TH imaging, with measures taken in M-mode or with AI software. We calculated mean bias and limits of agreement (LoA), and the intra-class correlation (ICC) coefficient with their 95% confidence intervals. Results Sixty volunteers were included; IVC was not visualized in five of them (n = 2, both SC and TH windows, 3.3%; n = 3 in TH approach, 5%). Compared with M-mode, AI showed good accuracy both for SC (IVCc: bias − 0.7%, LoA [− 24.9; 23.6]) and TH approach (IVCc: bias 3.7%, LoA [− 14.9; 22.3]). The ICC coefficients showed moderate reliability: 0.57 [0.36; 0.73] in SC, and 0.72 [0.55; 0.83] in TH. Comparing anatomical sites (SC vs TH), results produced by M-mode were not interchangeable (IVCc: bias 13.9%, LoA [− 18.1; 45.8]). When this evaluation was performed with AI, such difference became smaller: IVCc bias 7.7%, LoA [− 19.2; 34.6]. The correlation between SC and TH assessments was poor for M-mode (ICC = 0.08 [− 0.18; 0.34]) while moderate for AI (ICC = 0.69 [0.52; 0.81]). Conclusions The use of AI shows good accuracy when compared with the traditional M-mode IVC assessment, both for SC and TH imaging. Although AI reduces differences between sagittal and coronal IVC measurements, results from these sites are not interchangeable.