Artery Catheter Research Articles

A Novel Model of Venovenous Extracorporeal Membrane Oxygenation in Rats with Femoral Cannulation and Insights into Hemodynamic Changes.

The application of venovenous (VV) extracorporeal membrane oxygenation (ECMO) has gained wide acceptance for the treatment of acute severe respiratory failure. Since no rat model of VV ECMO therapy with femoral drainage has yet been described, although this cannulation strategy is commonly used in humans, this study aimed to establish such a model. Twenty male Lewis rats were randomly assigned to receive a sham procedure or VV ECMO therapy. After the inhalative induction of anesthesia, animals were intubated and the vascular accesses were placed surgically. While venous drainage was achieved through a modified multi-orifice 18 G cannula that was placed in the inferior vena cava through the femoral vein over a guide wire with an ultra-flexible tip, the venous return was realized via a shortened 20 G cannula into the jugular vein. Hemodynamic data were obtained from a tail artery and left ventricular pressure-volume catheter. Repetitive blood gas analyses were carried out, and systemic inflammation was measured using an enzyme-linked immunosorbent assay. While animals in the ECMO group showed adequate oxygenation and decarboxylation, there was no evidence of recirculation. VV ECMO therapy increased stroke volume (SV), cardiac output (CO), and left ventricular end-diastolic volume (LVEDV). ECMO-induced inflammation was reflected in increased levels of tumor necrosis factor alpha. However, no differences in interleukins 6 and 10 were seen. This study describes a frequently used cannulation strategy in humans for a rat model of VV ECMO. Despite successful oxygenation and decarboxylation, the oxygenated blood may reduce pulmonary vascular resistance and lead to an increased LVEDV, which is associated with increased SV and CO. This model allows us to answer research questions about topics such as intestinal microcirculation in further studies.

Impact of a 'Catheter Bundle' on Infection Rates and Economic Costs in the Intensive Care Unit: A Retrospective Cohort Study.

Catheter-related infections (CBRSIs) are a widespread problem that increase morbidity and mortality in intensive care unit (ICU) patients and management costs. The main aim of this study was to assess the prevalence of CBRSIs in an intensive care unit following international literature guidelines for managing vascular lines in critically ill patients. These guidelines include changing vascular lines every 7 days, using needle-free devices and port protectors, standardising closed infusion lines, employing chlorhexidine-impregnated dressings, and utilising sutureless devices for catheter securement. This single-centre retrospective observational study was conducted in a general Italian ICU. This study included all eligible patients aged > 1 year who were admitted between January 2018 and December 2022. During the study period, 1240 patients were enrolled, of whom 9 were diagnosed with a CRBSI. The infection rate per 1000 catheters/day was as follows: femorally inserted central catheter, 1.04; centrally inserted central catheter, 0.77; pulmonary arterial catheter 0.71, arterial catheter, 0.1; and peripherally inserted central catheter and continuous veno-venous haemodialysis dialysis catheters equal to 0. No difference in CRBSI was observed between the years included in the study (p = 0.874). The multivariate analysis showed an association between the diagnosis of CBRSI and Nursing Activities Score (per single point increase β = 0.04-95%CI: -0.01-0.09, p = 0.048), reason for ICU admission-trauma (β = 0.77-95%CI: -0.03-1.49, p = 0.039), and use of therapeutic hypothermia (β = 2.06, 95%CI: 0.51-3.20, p < 0.001). Implementing the study protocol revealed a cost of EUR 130.00/patient, equivalent to a daily cost of EUR 15.20 per patient. This study highlights the importance of implementing a catheter care bundle to minimise the risk of CRBSI and the associated costs in the ICU setting. A policy change for infusion set replacement every 7 days has helped to maintain the CRBSI rate below the recommended rate, resulting in significant cost reduction and reduced production of ICU waste.

Effects of volume management on free flap perfusion and metabolism in a large animal model study.

Free flap failure represents a substantial clinical burden. The role of intraoperative volume management remains controversial, with valid studies lacking. Here, using a large animal model, we investigated the influence of volume management on free flap perfusion and metabolism. Autotransfer of a musculocutaneous gracilis flap was performed on 31 German domestic pigs, with arterial anastomosis and catheterization of the pedicle vein for sequential blood sampling. Flap reperfusion was followed by induction of a hemorrhagic shock with maintenance for 30 min and subsequent circulation stabilization with crystalloid solution, crystalloid solution and catecholamine, autotransfusion or colloidal solution. Flap perfusion and oxygenation were periodically assessed using hyperspectral imaging. Flap metabolism was assessed via periodic blood gas analyses. Hyperspectral imaging revealed no difference in either superficial or deep tissue oxygen saturation, tissue hemoglobin or tissue water content between the test groups at any time point. Blood gas analyses showed that lactate levels were significantly increased in the group that received crystalloid solution and catecholamine, after circulatory stabilization and up to 2 h after. We conclude that, in hemorrhagic shock, volume management impacts acid-base balance in free flaps. Crystalloid solutions with norepinephrine increase lactate levels, yet short-term effects on flap perfusion seem minimal, suggesting that vasopressors are not detrimental.

Anesthesia management for percutaneous mitral valve repair in a patient with mitochondrial cardiomyopathy and low cardiac function: a case report

BackgroundMitochondrial cardiomyopathy occurs when impaired mitochondrial energy production leads to myocardial dysfunction. Anesthetic management in such cases is challenging due to risks of circulatory depression associated with anesthesia and mitochondrial dysfunction induced by anesthetics. Although there are reports of anesthetic management for patients with mitochondrial diseases, there are few reports specifically addressing cardiac anesthesia for patients with mitochondrial cardiomyopathy. We present a case where percutaneous mitral valve repair with MitraClip™ was successfully performed under remimazolam anesthesia in a patient with mitochondrial cardiomyopathy who developed functional mitral valve regurgitation due to low cardiac function and cardiomegaly.Case presentationA 57-year-old woman was diagnosed with chronic cardiac failure, with a 10-year history of dilated cardiomyopathy. She was diagnosed with mitochondrial cardiomyopathy 8 years ago. Over the past 2 years, her cardiac failure worsened, and mitral valve regurgitation gradually developed. Surgical intervention was considered but deemed too risky due to her low cardiac function, with an ejection fraction of 26%. Therefore, percutaneous MitraClip™ implantation was selected. After securing radial artery and central venous catheterization under sedation with dexmedetomidine, anesthesia was induced with a low dose of remimazolam 4 mg/kg/h. Anesthesia was maintained with remimazolam 0.35–1.0 mg/kg/h and remifentanil 0.1 μg/kg/min. Noradrenaline and dobutamine were administered intraoperatively, and the procedure was completed successfully without circulatory collapse. The patient recovered smoothly from anesthesia and experienced no complications. She was discharged on the eighth day after surgery.ConclusionAnesthesia management with remimazolam appears to be a safe and effective for MitraClip™ implantation in patients with mitochondrial cardiomyopathy.

Assisted Fluid Management and Sublingual Microvascular Flow During High-Risk Abdominal Surgery: A Randomized Controlled Trial.

Implementation of goal-directed fluid therapy (GDFT) protocols remains low. Protocol compliance among anesthesiologists tends to be suboptimal owing to the high workload and the attention required for implementation. The assisted fluid management (AFM) system is a novel decision support tool designed to help clinicians apply GDFT protocols. This system predicts fluid responsiveness better than anesthesia practitioners do and achieves higher stroke volume (SV) and cardiac index values during surgery. We tested the hypothesis that an AFM-guided GDFT strategy would also be associated with better sublingual microvascular flow compared to a standard GDFT strategy. This bicenter, parallel, 2-arm, prospective, randomized controlled, patient and assessor-blinded, superiority study considered for inclusion all consecutive patients undergoing high-risk abdominal surgery who required an arterial catheter and uncalibrated SV monitoring. Patients having standard GDFT received manual titration of fluid challenges to optimize SV while patients having an AFM-guided GDFT strategy received fluid challenges based on recommendations from the AFM software. In all patients, fluid challenges were standardized and titrated per 250 mL and vasopressors were administered to maintain a mean arterial pressure >70 mm Hg. The primary outcome (average of each patient's intraoperative microvascular flow index (MFI) across 4 intraoperative time points) was analyzed using a Mann-Whitney U test and the treatment effect was estimated with a median difference between groups with a 95% confidence interval estimated using the bootstrap percentile method (with 1000 replications). Secondary outcomes included SV, cardiac index, total amount of fluid, other microcirculatory variables, and postoperative lactate. A total of 86 patients were enrolled over a 7-month period. The primary outcome was significantly higher in patients with AFM (median [Q1-Q3]: 2.89 [2.84-2.94]) versus those having standard GDFT (2.59 [2.38-2.78] points, median difference 0.30; 95% confidence interval [CI], 0.19-0.49; P < .001). Cardiac index and SVI were higher (3.2 ± 0.5 vs 2.7 ± 0.7 l.min-1.m-2; P = .001 and 42 [35-47] vs 36 [32-43] mL.m-2; P = .018) and arterial lactate concentration was lower at the end of the surgery in patients having AFM-guided GDFT (2.1 [1.5-3.1] vs 2.9 [2.1-3.9] mmol.L-1; P = .026) than patients having standard GDFT strategy. Patients having AFM received a higher fluid volume but 3 times less norepinephrine than those receiving standard GDFT (P < .001). Use of an AFM-guided GDFT strategy resulted in higher sublingual microvascular flow during surgery compared to use of a standard GDFT strategy. Future trials are necessary to make conclusive recommendations that will change clinical practice.

Neurologic complications in patients receiving aortic versus subclavian versus femoral arterial cannulation for post-cardiotomy extracorporeal life support: results of the PELS observational multicenter study

BackgroundCerebral perfusion may change depending on arterial cannulation site and may affect the incidence of neurologic adverse events in post-cardiotomy extracorporeal life support (ECLS). The current study compares patients' neurologic outcomes with three commonly used arterial cannulation strategies (aortic vs. subclavian/axillary vs. femoral artery) to evaluate if each ECLS configuration is associated with different rates of neurologic complications.MethodsThis retrospective, multicenter (34 centers), observational study included adults requiring post-cardiotomy ECLS between January 2000 and December 2020 present in the Post-Cardiotomy Extracorporeal Life Support (PELS) Study database. Patients with Aortic, Subclavian/Axillary and Femoral cannulation were compared on the incidence of a composite neurological end-point (ischemic stroke, cerebral hemorrhage, brain edema). Secondary outcomes were overall in-hospital mortality, neurologic complications as cause of in-hospital death, and post-operative minor neurologic complications (seizures). Association between cannulation and neurological outcomes were investigated through linear mixed-effects models.ResultsThis study included 1897 patients comprising 26.5% Aortic (n = 503), 20.9% Subclavian/Axillary (n = 397) and 52.6% Femoral (n = 997) cannulations. The Subclavian/Axillary group featured a more frequent history of hypertension, smoking, diabetes, previous myocardial infarction, dialysis, peripheral artery disease and previous stroke. Neuro-monitoring was used infrequently in all groups. Major neurologic complications were more frequent in Subclavian/Axillary (Aortic: n = 79, 15.8%; Subclavian/Axillary: n = 78, 19.6%; Femoral: n = 118, 11.9%; p < 0.001) also after mixed-effects model adjustment (OR 1.53 [95% CI 1.02–2.31], p = 0.041). Seizures were more common in Subclavian/Axillary (n = 13, 3.4%) than Aortic (n = 9, 1.8%) and Femoral cannulation (n = 12, 1.3%, p = 0.036). In-hospital mortality was higher after Aortic cannulation (Aortic: n = 344, 68.4%, Subclavian/Axillary: n = 223, 56.2%, Femoral: n = 587, 58.9%, p < 0.001), as shown by Kaplan–Meier curves. Anyhow, neurologic cause of death (Aortic: n = 12, 3.9%, Subclavian/Axillary: n = 14, 6.6%, Femoral: n = 28, 5.0%, p = 0.433) was similar.ConclusionsIn this analysis of the PELS Study, Subclavian/Axillary cannulation was associated with higher rates of major neurologic complications and seizures. In-hospital mortality was higher after Aortic cannulation, despite no significant differences in incidence of neurological cause of death in these patients. These results encourage vigilance for neurologic complications and neuromonitoring use in patients on ECLS, especially with Subclavian/Axillary cannulation.Graphical abstract

Continuous sepsis trajectory prediction using tensor-reduced physiological signals

The quick Sequential Organ Failure Assessment (qSOFA) system identifies an individual’s risk to progress to poor sepsis-related outcomes using minimal variables. We used Support Vector Machine, Learning Using Concave and Convex Kernels, and Random Forest to predict an increase in qSOFA score using electronic health record (EHR) data, electrocardiograms (ECG), and arterial line signals. We structured physiological signals data in a tensor format and used Canonical Polyadic/Parallel Factors (CP) decomposition for feature reduction. Random Forests trained on ECG data show improved performance after tensor decomposition for predictions in a 6-h time frame (AUROC 0.67 ± 0.06 compared to 0.57 ± 0.08, p=0.01\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p = 0.01$$\\end{document}). Adding arterial line features can also improve performance (AUROC 0.69 ± 0.07, p<0.01\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p < 0.01$$\\end{document}), and benefit from tensor decomposition (AUROC 0.71 ± 0.07, p=0.01\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p = 0.01$$\\end{document}). Adding EHR data features to a tensor-reduced signal model further improves performance (AUROC 0.77 ± 0.06, p<0.01\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p < 0.01$$\\end{document}). Despite reduction in performance going from an EHR data-informed model to a tensor-reduced waveform data model, the signals-informed model offers distinct advantages. The first is that predictions can be made on a continuous basis in real-time, and second is that these predictions are not limited by the availability of EHR data. Additionally, structuring the waveform features as a tensor conserves structural and temporal information that would otherwise be lost if the data were presented as flat vectors.

Physiological effects and safety of bed verticalization in patients with acute respiratory distress syndrome

BackgroundTrunk inclination in patients with Acute Respiratory Distress Syndrome (ARDS) in the supine position has gained scientific interest due to its effects on respiratory physiology, including mechanics, oxygenation, ventilation distribution, and efficiency. Changing from flat supine to semi-recumbent increases driving pressure due to decreased respiratory system compliance. Positional adjustments also deteriorate ventilatory efficiency for CO2 removal, particularly in COVID-19-associated ARDS (C-ARDS), indicating likely lung parenchyma overdistension. Tilting the trunk reduces chest wall compliance and, to a lesser extent, lung compliance and transpulmonary driving pressure, with significant hemodynamic and gas exchange implications.MethodsA prospective, pilot physiological study was conducted on early ARDS patients in two ICUs at CHU Clermont-Ferrand, France. The protocol involved 30-min step gradual verticalization from a 30° semi-seated position (baseline) to different levels of inclination (0°, 30°, 60°, and 90°), before returning to the baseline position. Measurements included tidal volume, positive end-expiratory pressure (PEEP), esophageal pressures, and pulmonary artery catheter data. The primary endpoint was the variation in transpulmonary driving pressure through the verticalization procedure.ResultsFrom May 2020 through January 2021, 30 patients were included. Transpulmonary driving pressure increased slightly from baseline (median and interquartile range [IQR], 9 [5–11] cmH2O) to the 90° position (10 [7–14] cmH2O; P < 10–2 for the overall effect of position in mixed model). End-expiratory lung volume increased with verticalization, in parallel to decreases in alveolar strain and increased arterial oxygenation. Verticalization was associated with decreased cardiac output and stroke volume, and increased norepinephrine doses and serum lactate levels, prompting interruption of the procedure in two patients. There were no other adverse events such as falls or equipment accidental removals.ConclusionsVerticalization to 90° is feasible in ARDS patients, improving EELV and oxygenation up to 30°, likely due to alveolar recruitment and blood flow redistribution. However, there is a risk of overdistension and hemodynamic instability beyond 30°, necessitating individualized bed angles based on clinical situations.Trial registration ClinicalTrials.gov registration number NCT04371016, April 24, 2020.

Validation of a Novel Method for Noninvasive Mixed Venous Oxygen Saturation Monitoring in Anesthetized Children.

Mixed venous oxygen saturation (SvO 2 ) is a critical variable in the assessment of oxygen supply and demand but is rarely used in children due to the invasive nature of pulmonary artery catheters. The aim of this prospective, observational study was to investigate the accuracy of noninvasively measured SvO 2 acquired by the novel capnodynamic method, based on differential Fick equation (Capno-SvO 2 ), against gold standard CO-oximetry. Capno-SvO 2 was compared to SvO 2 measured by pulmonary artery blood gas CO-oximetry in children undergoing cardiac catheter interventions and subjected to moderate hemodynamic challenges. Bland-Altman analysis was used to describe the agreement of absolute values between CO-oximetry and Capno-SvO 2 , and a concordance rate was calculated to evaluate the ability of Capno-SvO 2 to track change. Twenty-five procedures were included in the study. Capno-SvO 2 showed a bias toward CO-oximetry of +3 percentage points; upper and lower limits of agreement were +11 percentage points (95% confidence interval [CI], 9-14) and -5 percentage points (95% CI, -8 to -3), respectively. The concordance rate was 92% (95% CI, 89-96). In conclusion, this first clinical application of a novel concept for noninvasive SvO 2 monitoring without the need for a pulmonary artery catheter indicates that Capno-SvO 2 generates absolute values and trending capacity in close agreement with the gold standard reference method.

Arterial catheter outcomes in intensive care: An analysis of 1117 patients

BackgroundAccess to arterial circulation through arterial catheters (ACs) is crucial for monitoring and decision-making in intensive care units (ICU) but carries the risk of complications including bloodstream infection (BSI). MethodsWe conducted a secondary analysis of data from four randomised controlled trials in Australian ICUs, investigating the efficacy of different AC interventions. De-identified data were combined into a single dataset, and per-patient outcomes analysed. The primary outcome was AC-BSI, defined as laboratory-confirmed bloodstream infection (LCBI) type 1 or 2, with a concurrent local infection. All-cause AC failure was defined as any unplanned removal. AC infection and failure were reported as rates per 1000 catheter days and hours. ResultsData from 1117 adult patients were analysed. Mean age was 58.8 years (±16.6); and 41% (n = 462) were male. Median AC dwell time was 110 h (IQR 28.3–168.0). There was one case (<0.1%; 0.18/1000 catheter days [95% CI 0.03–1.29]) of AC-BSI, and 14 cases of LCBI (1%; 13 LCBI-1 and 1 LCBI-2; 2.54/1000 catheter days [95% CI 1.51–4.30]). LCBI were most commonly Enterococcus faecalis; Escherichia coli and Klebsiella pneumoniae. There were four cases of local infection (<1%; 0.73/1000 catheter days [95% CI 0.27–1.94]). Overall AC failure rate was 13% (n = 146) or 26.53/1000 catheter days (95% CI 22.56–31.20). ConclusionThis study identified a relatively low incidence of complications. This is likely reflective of poor monitoring of ACs in intensive care. Better surveillance and a rigorous prospective evaluation of AC outcomes is required to understand the true risk ACs pose to critically ill patients.

Ultrasonic Doppler as a guide for feline peripheral arterial catheterization.

The study aimed to determine if an ultrasonic Doppler-guided technique (UDGT) leads to improved placement efficacy (time, success) of feline dorsal pedal arterial catheters vs the traditional palpation-guided technique (TPT). A total of 26 adult, client-owned cats requiring sedation or general anesthesia for any reason, aged >12 months and weighing >3.0 kg, and with Doppler blood pressure measurements of at least 80 mmHg were enrolled. Each hindlimb was randomly assigned for dorsal pedal arterial catheterization using either the UDGT or TPT. With the UDGT, the location of the artery was identified by an audible sound using the Doppler. Successful catheter placement was confirmed by visualization of an arterial pressure waveform using a transducer and monitor system attached to the catheter. The Kaplan-Meier method and log-rank test were used to compare the two techniques. The overall proportion of successful arterial catheterization was 17% (9/52): 19% (5/26) via UDGT and 15% (4/26) via TPT. Among successful arterial catheterizations (n = 9), the mean time to catheterization was 339 ± 198 s: 328 ± 237 s (n = 5) with UDGT and 353 ± 171 s (n = 4) with TPT. The log-rank test showed the two techniques were not significantly different in likelihood of successful arterial catheter placement or time to successful catheterization (P = 0.698). An arterial flash occurred in 62% (32/52) of the limbs, 58% (15/26) with the UDGT and 65% (17/26) with the TPT. Complications (self-limiting bruising, hematoma formation) were observed equally between UDGT (3/26 limbs) and TPT (3/26 limbs) in six cats. The UDGT did not improve the efficacy of catheter placement compared with the TPT. Few complications were associated with arterial catheterization.

Clinical Utility of Ultrasonographic Guidance for Arterial Catheterization in Patients with Obesity: A Randomized Controlled Trial

ObjectivesWe aimed to compare the success and complication rates of radial artery catheterizations between ultrasound guidance and conventional palpation technique in obese patients by anesthesia residents with similar levels of experience in both methods. Another objective was to measure the skin-to-artery distance of radial, brachial, and dorsalis pedis arteries using ultrasound with standardized anatomical landmarks. DesignProspective, randomized controlled trial SettingSingle tertiary center ParticipantsEighty adults with a body mass index (BMI) ≥ 30 kg·m-2 InterventionsUltrasound guidance or conventional palpation method Measurements and Main ResultsThe primary outcome was the first-attempt success rate of arterial catheterizations. The skin-to-artery distance of the radial artery in the BMI groups of 40–49 and ≥ 50 kg/m2 was significantly greater than that of the BMI group of 30–39 kg·m-2, mean difference: 1.0 mm [95% confidence interval (CI): 0.4 – 1.7, p=0.0029] for BMI 40–49 vs. 30–39 kg/m2 and 1.5 mm (95% CI: 0.6 – 2.4, p=0.0015) for ≥ 50 vs. 30–39 kg·m-2. Similar findings were observed for the brachial artery. BMI was inversely associated with first-attempt success rates (p=0.0145) and positively with time to successful catheterization (p=0.0271). The first-attempt success and vascular complication rates of catheterization did not significantly differ between the ultrasound guidance group (65.0%; 52.5%) and the conventional palpation group (70.0%, p=0.6331; 57.5%, p=0.6531). ConclusionOur results do not support routine uses of ultrasonography during radial arterial catheterizations for obese adults when junior practitioners performed the procedure.

Flow reduction due to arterial catheterization during stroke treatment - A computational study using a distributed compartment model.

The effectiveness of various stroke treatments depends on the anatomical variability of the cerebral vasculature, particularly the collateral blood vessel network. Collaterals at the level of the Circle of Willis and distal collaterals, such as the leptomeningeal arteries, serve as alternative avenues of flow when the primary pathway is obstructed during an ischemic stroke. Stroke treatment typically involves catheterization of the primary pathway, and the potential risk of further flow reduction to the affected brain area during this treatment has not been previously investigated. To address this clinical question, we derived the lumped parameters for catheterized blood vessels and implemented a corresponding distributed compartment (0D) model. This 0D model was validated against an experimental model and benchmark test cases solved using a 1D model. Additionally, we compared various off-center catheter trajectories modeled using a 3D solver to this 0D model. The differences between them were minimal, validating the simplifying assumption of the central catheter placement in the 0D model. The 0D model was then used to simulate blood flows in realistic cerebral arterial networks with different collateralization characteristics. Ischemic strokes were modeled by occlusion of the M1 segment of the middle cerebral artery in these networks. Catheters of different diameters were inserted up to the obstructed segment and flow alterations in the network were calculated. Results showed up to 45% maximum blood flow reduction in the affected brain region. These findings suggest that catheterization during stroke treatment may have a further detrimental effect for some patients with poor collateralization.

Instantaneous Right Ventricular to Pulmonary Artery Systolic Pressure Difference in Cardiac Surgery: A Retrospective and Prospective Cohort Study

BackgroundDuring cardiac surgery, right ventricular outflow tract obstruction (RVOTO) is defined as an instantaneous pressure difference ≥ 6 mm Hg between right ventricular systolic pressure (RVSP) and pulmonary artery systolic pressure (PASP), for ≥ 5 minutes. Risk factors for RVOTO remain poorly understood. This cohort study was designed to evaluate the incidence, characteristics, and outcomes of the patients who experienced RVOTO. MethodsInstantaneous pressure difference between RVSP and PASP was measured by means of a pulmonary artery catheter with a right ventricular port during cardiac surgery from a retrospective (n = 295) and a prospective (n = 105) cohort. ResultsFrom the retrospective and prospective cohorts, respectively, incidence of RVOTO was 30.2% and 36.2% before cardiopulmonary bypass (CPB) initiation and 43.7% and 47.6% after CPB separation. Before CPB initiation, patients with RVOTO had higher cardiac output (4.2 ± 1.5 vs 3.8 ± 1.1 L/min; P = 0.033) and received more inhaled epoprostenol (79% vs 61%; P = 0.005) and inotropes (66% vs 51%; P = 0.016) compared with those without RVOTO. After CPB separation, patients with RVOTO had higher heart rate (62 ± 15 vs 58 ± 13 beats/min; P = 0.011), cardiac output (4.1 ± 1.4 vs 3.7 ± 1.1 L/min; P = 0.003), and CPB duration (90 ± 45 vs 77 ± 30 min, P = 0.014), had lower fluid balance (758 ± 1123 vs 1063 ± 1089 mL; P = 0.021), and were more exposed to intratracheal milrinone (12% vs 4%; P = 0.015) compared with those without RVOTO. The time with persistent organ dysfunction (TPOD) at 28 days after surgery was similar among patients who had an RVOTO event, before CPB initiation or after CPB separation, compared with those who did not. ConclusionsRVOTO is common in cardiac surgery. However, it is not associated with longer TPOD.

Reducing Central Line-Associated Bloodstream Infections With a Multipronged Nurse-Driven Approach.

Despite implementation of central catheter bundles, central line [catheter]-associated bloodstream infections (CLABSIs) remain a preventable hospital-acquired infection. A new population of patients with pulmonary artery catheters was introduced to the cardiac progressive care unit, increasing central catheter days, device use, and CLABSI rate. A quality improvement project was conducted. Nursing staff implemented a standardized central catheter rounding process 3 days a week to critically assess all central catheter dressings, deter-mine the necessity of each central catheter, and educate patients on the importance of keeping central catheter dressings clean, dry, and intact. Data were collected during central catheter rounds for each patient, entered in an electronic survey tool via mobile devices, and analyzed. From July 2019 through June 2022, a total of 2692 rounds were conducted for 707 individual patients with 3064 central catheters. Main interventions were dressing management, monitoring insertion site bleeding that extended beyond edges of the chlorhexidine gluconate pad, treating patients' allergies to products, and maintaining sustainability within the unit. Central catheter rounds decreased the CLABSI rate from 1.86 to 0.0 despite the continued increase in central catheter days. Central catheter dressing assessment, intervention, and education help reduce CLABSIs. Central catheter rounds are an important adjunct to the CLABSI bundle. A central catheter dressing management algorithm helps nurses decide when to change a dressing and which type of dressing to use.

Point-of-Care Ultrasound: A Vital Tool for Anesthesiologists in the Perioperative and Critical Care Settings.

Point-of-care ultrasound (POCUS) is an essential skill in various specialties like anesthesiology, critical care, and emergency medicine. Anesthesiologists utilize POCUS for quick diagnosis and procedural guidance in perioperative and critical care settings. Key applications include vascular ultrasound for challenging venous and arterial catheter placements, gastric ultrasound for aspiration risk assessment, airway ultrasound, diaphragm ultrasound, and lung ultrasound for respiratory assessment. Additional utilities of POCUS can include multi-organ POCUS evaluation for undifferentiated shock or cardiac arrest, ultrasound-guided central neuraxial and peripheral nerve blocks, focused cardiac ultrasound, and novel applications such as venous excess ultrasound. This review highlights these POCUS applications in perioperative and intensive care and summarizes the latest evidence of their accuracy and limitations.

Peripheral arterial catheters in extremely preterm infants born at less than 28 weeks of gestation—a single-center experience

The aim of this study was to perform a retrospective data analysis of established peripheral artery catheters (pAC) in extremely preterm infants. The primary outcome was the pAC life span and its correlation to gestational age, birth weight, localizations, and pAC removal. Retrospective data analysis of electronic patient records of all extremely preterm infants (born less than 28 weeks gestation) admitted to the neonatal intensive care unit in Graz (Austria) between January 2014 and December 2020. A total of 196 preterm infants with a median (IQR) gestational age of 25.7 (24.6–26.6) weeks and a birth weight of 730 (614–898) g were included. In 155 (79%) of these preterm infants, 286 pAC and six umbilical artery catheters were inserted successfully. The first pAC was inserted 2.5 (1.4–7.4) h after birth, and the median pAC life span was 57.5 (22.–107.2) h. Gestational age, birth weight, and catheter localization did not correlate with the pAC life span. The pAC localizations were the radial artery (63%), tibial posterior artery (21%), ulnar artery (6%), dorsal artery of the foot (6%), others (1%), and not documented (3%). Adverse reactions including temporarily impaired peripheral perfusion, local inflammation, extravasation, or bleeding were reported in 13% of all pAC, but none of these resulted in long-term sequelae. A median (IQR) of 9 (5–18) arterial blood samples were drawn via pAC, resulting in a notable reduction of pain stimuli.Conclusion: The use of pAC in extremely preterm infants is feasible and safe. Neither gestational age, birth weight nor localization did affect the life span of pAC. No long-term sequelae were observed, and pain events were reduced by using pAC for blood drawing.What is Known:• Peripheral artery catheters can be used for continuous blood pressure measurement and blood draw even in extremely preterm infants.• (Severe) adverse reactions such as bleeding, necrosis, or amputation occur between 1 and 4%.• What is New:• The median peripheral arty catheter life span is 58 h and is not affected by gestational age, birth weight, nor localization.• A median of nine blood samples can be taken per each single pAC and, therefore, prevent pain events in extremely preterm infants.

Coronary angiography following transcatheter aortic valve replacement: Insights from the SWEDEHEART registry.

Transcatheter aortic valve replacement (TAVR) is the most common treatment in patients with symptomatic severe aortic stenosis (AS). As concomitant coronary artery disease is common in AS patients, access to the coronary arteries following TAVR is of increasing importance. This study evaluated the incidence and risk factors for unplanned coronary angiography following TAVR and, using fluoroscopic time as a surrogate, analyzed the complexity of coronary artery cannulation. All patients who underwent TAVR in Sweden between 2008 and 2022 were identified using the SWEDEHEART registry. The cumulative incidence of coronary angiography after TAVR was analyzed with mortality as a competing risk. Angiography and PCI complexity were analyzed using fluoroscopic time and compared across different transcatheter heart valve designs. Out of 9806 patients, 566 subsequently required coronary angiography. The incidence was highest for three-vessel and/or left main disease. Younger age, the extent of prior coronary artery disease, and peripheral vascular disease were associated with an increased risk of coronary angiography. Fluoroscopy time was increased in TAVR patients compared to the control group with the longest fluoroscopy times observed in cases involving supra-annular and self-expanding valves. The incidence of coronary angiography following TAVR is still low. Younger patients and patients with concomitant coronary artery disease have a higher risk. Procedural time is longer in patients with a previous THV replacement. As TAVR is emerging as the first-line treatment in patients with longer life expectancy, facilitating coronary access is an important factor when considering which THV device to implant.

Association between intra-arterial catheterization and mortality of acute heart failure patients without shock in ICU: A retrospective study

BackgroundAcute heart failure necessitates intensive care, and arterial catheterization is a commonly performed invasive procedure in the intensive care unit (ICU). We aimed to investigate the association between arterial catheterization and outcomes in acute heart failure patients without shock. MethodsWe utilized MIMIC-IV database records for acute heart failure patients at Beth Israel Deaconess Medical Center from 2008 to 2019. Employing doubly robust estimation, we examined the relationship between arterial catheterization and outcomes, including 28-day, 90-day, in-hospital mortality, and ICU-free days within 28 days. ResultsOf 6936 patients identified, 2078 met inclusion criteria; 347 underwent arterial catheterization during their ICU stay. We observed no significant difference in 28-day mortality (odds ratio [OR]: 0.61, 95 % confidence interval [CI]: 0.31–1.21, P = 0.155), though catheterization was associated with reduced in-hospital mortality (OR: 0.41, 95 % CI: 0.14–0.65, P = 0.02). No significant effects were observed on 90-day mortality or ICU-free days within 28 days. ConclusionOur findings suggest that arterial catheterization is not associated with 28- and 90-day mortality rates in acute heart failure patients without shock but is linked to lower in-hospital mortality. Additional research and consensus are required to determine the appropriate utilization of arterial catheterization in patients.

A retrospective study of the effects of a vasopressor bolus on systolic slope (dP/dt) and dynamic arterial elastance (Eadyn)

BackgroundTo enhance the utility of functional hemodynamic monitoring, the variables systolic slope (dP/dt) and dynamic arterial elastance (Eadyn) are calculated by the Hypotension Prediction Index (HPI) Acumen® Software. This study was designed to characterize the effects of phenylephrine and ephedrine on dP/dt and Eadyn.MethodsThis was a retrospective, non-randomized analysis of data collected during two clinical studies. All patients required intra-operative controlled mechanical ventilation and had an indwelling radial artery catheter connected to an Acumen IQ sensor. Raw arterial pressure waveform data was downloaded from the patient monitor and all hemodynamic measurements were calculated off-line. The anesthetic record was reviewed for bolus administrations of either phenylephrine or ephedrine. Cardiovascular variables prior to drug administration were compared to those following vasopressor administrations. The primary outcome was the difference for dP/dt and Eadyn at baseline compared with the average after the bolus administration. All data sets demonstrated non-normal distributions so statistical analysis of paired and unpaired data followed the Wilcoxon matched pairs signed-rank test or Mann-Whitney U test, respectively.Results201 doses of phenylephrine and 100 doses of ephedrine were analyzed. All data sets are reported as median [95% CI]. Mean arterial pressure (MAP) increased from 62 [54,68] to 78 [76,80] mmHg following phenylephrine and from 59 [55,62] to 80 [77,83] mmHg following ephedrine. Stroke volume and cardiac output both increased. Stroke volume variation and pulse pressure variation decreased. Both drugs produced significant increases in dP/dt, from 571 [531, 645] to 767 [733, 811] mmHg/sec for phenylephrine and from 537 [509, 596] to 848 [779, 930] mmHg/sec for ephedrine. No significant changes in Eadyn were observed.ConclusionBolus administration of phenylephrine or ephedrine increases dP/dt but does not change Eadyn. dP/dt demonstrates potential for predicting the inotropic response to phenylephrine or ephedrine, providing guidance for the most efficacious vasopressor when treating hypotension.Trial registrationData was collected from two protocols. The first was deemed to not require written, informed consent by the Institutional Review Board (IRB). The second was IRB-approved (Effect of Diastolic Dysfunction on Dynamic Cardiac Monitors) and registered on ClinicalTrials.gov (NCT04177225).