Hemodynamic Effects Research Articles

Correction: Chen et al. Hemodynamic Effects of Subaortic Stenosis on Blood Flow Characteristics of a Mechanical Heart Valve Based on OpenFOAM Simulation. Bioengineering 2023, 10, 312

In the original publication [...]

Iron homeostasis, recycling and vulnerability in the stressed kidney: A neglected dimension of iron-deficient heart failure.

The available evidence suggests that the kidney may contribute importantly to the development of an iron deficiency state in patients with heart failure and may be injured by therapeutic efforts to achieve iron repletion. The exceptional workload of the proximal renal tubule requires substantial quantities of iron for ATP synthesis, which it derives from Fe3+ bound to transferrin in the bloodstream. Following ferrireduction, Fe2+ is conveyed by divalent transporters (e.g. DMT1) out of the endosome of the proximal renal tubule, and highly reactive Fe2+ can be directed to the mitochondria, sequestered safely in a ferritin nanocage or exported through the actions of hepcidin-inhibitable ferroportin. The actions of ferroportin, together with transferrin endocytosis and DMT1-mediated transport, play a key role in the recycling of iron from the tubular fluid into the bloodstream and preventing the loss of filtered iron in the urine. Activation of endogenous neurohormonal systems and proinflammatory signalling in heart failure decrease megalin-mediated uptake and DMT1 expression, and increase hepcidin-mediated suppression of ferroportin, promoting the loss of iron in the urine and contributing to the development of an iron deficiency state. Furthermore, the failure of ferroportin-mediated efflux at the basolateral membrane heightens the susceptibility of the renal tubules to cytosolic excesses of Fe2+, causing lipid peroxidation and synchronized cell death (ferroptosis) through the iron-dependent free radical theft of electrons from lipids in the cell membrane. Ferroptosis is a central mechanism to most disorders that can cause acute and chronic kidney disease. Short-term bolus administration of intravenous iron can cause oxidative stress and is accompanied by markers of renal injury. Experimentally, long-term maintenance of an iron-replete state is accompanied by accelerated loss of nephrons, oxidative stress, inflammation and fibrosis. Intravenous iron therapy increases glomerular filtration rate rapidly in patients with heart failure (perhaps because of a haemodynamic effect) but not in patients with chronic kidney disease, and the effects of intravenous iron on the progression of renal dysfunction in the long-term trials - AFFIRM-AHF, IRONMAN and HEART-FID - have not yet been reported. Given the potential role of dysregulated renal iron homeostasis in the pathogenesis of iron deficiency and the known vulnerability of the kidney to intravenous iron, the appropriate level of iron repletion with respect to the risk of acute and chronic kidney injury in patients with heart failure requires further study.

Hemodynamic effects of treatment with the ketone body 3-hydroxybutyrate in cardiogenic shock - a randomized, controlled, assessor-blinded porcine trial

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Novo Nordisk Foundation Independent Research Fund DK. Background Cardiogenic shock (CS) is a life-threatening disease with limited evidence-based treatment options. Treatment with the ketone body 3-hydroxybutyrate (3-OHB) induces favorable hemodynamic effects in patients with heart failure and CS. It increases cardiac output (CO) and left ventricular (LV) ejection fraction (LVEF) while reducing cardiac filling pressures. Yet, whether treatment with 3-OHB demonstrates beneficial hemodynamic effects during acute ischemic LV stunning in CS must be fully elucidated. This study aimed to examine the acute hemodynamic effects and underlying cardiovascular mechanisms of 3-OHB infusion in the acute phase of LV stunning in a porcine model of ischemic CS. Methods Sixteen 60-kg-pigs were included in a randomised, controlled, assessor-blinded crossover study. CS was achieved by repeated, slow injections of microspheres into the left main coronary artery. CS was defined as ≥30% reduction in CO and/or mixed venous saturation (SVO2). Upon the onset of CS, following a one-hour no-touch period, the pigs received an infusion with 3-OHB and isoosmolar, isovolumic saline (control) for two hours each in random order. Infusion periods were separated by a one-hour washout period. CO (primary endpoint), SVO2, and pulmonary pressures were measured by right heart catheterization. A pressure-volume admittance catheter was placed in the LV to measure LVEF, contractility (the slope of end systolic pressure-volume relationship, denoded as Ees), afterload (arterial elastance, Ea, and end-systolic pressure, ESP), preload (end-diastolic volume, EDV), and work-related parameters. Results CS was successfully achieved in all randomized animals. CO decreased by 36% from 4.5±1.0 L/min to 2.9±0.5 L/min (p<0.001) and SVO2 decreased by 31% from 55.0±8.1% to 37.7±5.8% (p<0.001). During 3-OHB infusion, CO increased by 0.9 L/min (95% CI: 0.4 to 1.3 L/min) compared with the control infusion. In parallel, Ees increased by 0.22 mmHg/mL (95% CI: 0.08 to 0.37 mmHg/mL), LVEF improved by 7 percentage points (95%CI: 1 to 13 percentage points) and cardiac efficiency increased by 6 percentage points (95%CI: 1 to 11 percentage points). Systemic vascular resistance was decreased by 479 dyn*cm5 (95% CI: 736 to 221 dyn*cm5); Ea and ESP remained similar. Heart rate was increased during 3-OHB infusion by 21 bpm (95% CI: 11 to 32 bpm) while no significant change was observed in stroke volume (p=0.6). Conclusion Treatment with 3-OHB improved CO, LVEF, and cardiac efficiency in CS. The increase was mediated through increased ventricular contractility and decreased peripheral resistance accompanied by increased heart rate.CO, Ees and cardiac efficiencyEndpoint parameters during 3-OHB

Impact of intra-aortic balloon pump diastolic augmentation on survival in patients with cardiogenic shock

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): PI funded - Jason Katz, MD Background Temporary MCS devices are routinely used in pts with CS. The most commonly used temporary MCS device worldwide is the IABP, which increases DBP, enhances coronary perfusion, and improves cardiac output. No randomized controlled trial has demonstrated its superiority over standard care practices and observational data suggest heterogeneity in its hemodynamic effect. IABP response likely depends on optimizing several pt- and device-related factors, most notably the ability to augment DBP. Unfortunately, a notable gap exists in defining the association of augmented DBP (aDBP) with mortality, and none of the contemporary clinical trials have systematically assessed this concept. Purpose In a cohort of pts with CS, the goal was to investigate the association between aDBP and survival in those supported with an IABP. Methods In a retrospective analysis of prospectively collected data from pts with CS who underwent IABP placement at Duke from 1/2010-6/2021 we describe baseline characteristics and discharge outcomes stratified by aDBP. Pre-insertion DBP was measured immediately prior to IABP, while post-insertion aDBP was collected 2 hrs following device placement. Success was defined as survival to hospital discharge. Death prior to discharge, hospice care, or escalation to ECMO, Impella, durable LVAD, or heart transplant were all considered a non-successful result. A multivariate logistic regression model was created to assess the association of aDBP on outcome, adjusting for pre-IABP DBP, age, sex, race, history of MI and HF. Results 514 CS pts were identified, of which 470 (91%) had available pre-insertion DBP and post-insertion aDBP. The modal age was 65-74 yrs, 75% were male, 54% were white, 85% had prior HF, and 34% had prior MI. Figure 1A shows the distribution of pre-insertion DBP (median 67 mmHg) and post-insertion aDBP (median 106 mmHg). Overall, 49% of pts had a successful outcome. There was a u-shaped relationship between aDBP and the likelihood of success; as an example, for a modeled pt (65-75yo male, pre-insertion DBP of 66 mmHg, no HF or MI), the predicted probability of a successful outcome increased from 10% to 65% as aDBP rose to 120 mmHg, followed by a subsequent decline (Figure 1B). The relationship between either absolute or relative change in aDBP over baseline, on the other hand, was no longer u-shaped, but rather linear. After multivariate adjustment, only aDBP was associated with success such that every 10mmHg increase in aDBP over baseline was associated with improved survival to hospital discharge (OR 1.12, p=0.03). Conclusions In a cohort of pts with CS managed with an IABP, we report for the first time that aDBP is associated with improved survival to hospital discharge. Future prospective and randomized analyses should aim to capture degree of augmentation when studying counterpulsation devices, and this may help to clarify the currently controversial role of the IABP in contemporary CS care.

PEEP trial and effect on hemodynamic in cardiogenic shock

Abstract Funding Acknowledgements None. Introduction Congestion is a paramount pathophysiological driver in patients with cardiogenic shock. Almost half of patients admitted due to cardiogenic shock undertake mechanical ventilation although ventilatory parameter, and their potential hemodynamic effect on the hemodynamic and congestion profile are often neglected. Purpose We sought to evaluate the hemodynamic effect of positive end-expiratory pressure (PEEP) titration on patients admitted to intensive care unit for CS. Methods We perform PEEP titration trial on patients undertaking mechanical ventilation for respiratory failure related to CS. The trial consisted in 3 steps of PEEP increase from 5 to 15 cmH2O. For each step arterial saturation, right atrial -RAP- and systemic blood pressure along with heart rate and respiratory mechanics (tidal volume-TV-, dynamic lung compliance- CLdyn, driving- Δ- and plateau pressure- Ppl) were measured. All the measures were taken at end-expiration; RAP trace was analyzed and systolic, mean and diastolic component collected. The final PEEP was decided based on the best matching between saturation, CLdyn and TV. Descriptive and repeated measures with Bonferroni correction were applied as statistical analysis (IBM SPSS 29). Results Twelve patients were included (10 male, 66 ± 7 years old; 8 acute myocardial infarction and 4 acute heart failure). At baseline the mean RAP was 8.44 (± 2.32) ; SBP 106 (IQR 92-112), HR 94 (IQR 88 - 102) Δ and Ppl pressures respectively 7.42 (± 0.79) and 12.08 (± 0.79, ),VT 427(± 65.42) and CLdyn 58.3 (± 7.1). The right atrial pressure (RAP) differed between AMI and AHDF (8.25 ± 2.25 vs 20.25 ± 1.5; p < 0.001), so HR did (113 ± 3.4 versus 96 ± 3.2 betas per minutes; p 0.015). RAP varied consistently during the PEEP trial (either sRAP, dRAP and mRAP- Table and Figure 1). The TV changed signficnatly between the 1st and 3rd step (p 0.004) and the CLdyn varied consistently throughout the 3 steps of the PEEP trial (p <0.001). A significant difference were observed according to aetiology in RAP (AMI Vs ADHF, eman difference 2.4 versus 4.3 mmHg) and in CLdyn (AMI Vs ADHF mean difference 12.31 vs 8 .65, p < 0.01) but not in the other parameters evaluated (p > 0.05). Conclusion This is the first, small, study evaluating the effect of positive pressure ventilation in CS patients according to etiologies. As previously demonstrated PEEP influences the right side hemodynamic by increasing the RAP, although resulting in better CLdyn. The extent of the effect of PEEP increased may be dependent on the underlying aetiology of CS. Considering that the sample size is extremely limited, these results advocate a wider validation. However, the positive pressures induced by the ventilation in patient with CS should be taken in consideration when the comprehensive evaluation of hemodynamic to define congestion profile and phenotype are performed.Table 1.Hemodynamic parametersGraph PEEP vs RAP

Influence of Blood Pressure Reduction on Pulse Wave Velocity in Primary Hypertension: A Meta-Analysis and Comparison With an Acute Modulation of Transmural Pressure.

Increased arterial stiffness and pulse wave velocity (PWV) of the aorta and large arteries impose adverse hemodynamic effects on the heart and other organs. Antihypertensive treatment reduces PWV, but it is unknown whether this results from an unloading of stiffer elements in the arterial wall or is due to an alternate functional or structural change that might differ according to class of antihypertensive drug. We performed a systematic review and meta-analysis of the effects of different antihypertensive drug classes and duration of treatment on PWV with and without adjustment for change in mean arterial blood pressure (BP; study 1) and compared this to the change in PWV after an acute change in transmural pressure, simulating an acute change in BP (study 2). A total of 83 studies involving 6200 subjects were identified. For all drug classes combined, the reduction of PWV was 0.65 (95% CI, 0.46-0.83) m/s per 10 mm Hg reduction in mean arterial BP, a change similar to that induced by an acute change in transmural pressure in a group of hypertensive subjects. When adjusted for change in mean arterial BP, the reduction in PWV after treatment with beta-blockers or diuretics was less than that after treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor antagonists or calcium channel antagonists. Reduction in PWV after antihypertensive treatment is largely explained by the reduction in BP, but there are some BP-independent effects. These might increase over time and contribute to better outcomes over the long term, but this remains to be demonstrated in long-term clinical trials.

Comparison of Hemodynamic Effect of Propofol and Ketofol during Induction of Anaesthesia in General Surgery Patients

Objective: To determine the comparison of homodynamic effect of propofol and ketofol duringinduction in general surgery patients.Study design: Randomized control trialSetting: Department of Anesthesia, Surgical ICU and Pain management, Civil Hospital Karachi.Duration: Seven months from June 2019 to January 2020.Methods: Patients scheduled for elective general surgery procedures, aged 20 to 60 years, bothmale and female patients were included. Patients were randomly allocated into two groups.Group A received a combination of ketofol while Group B received propofol as the inductionagent. After recording of the base line values of mean arterial pressure patient was induced usingpropofol or ketofol. Mean arterial pressure readings were noted at 30 seconds after druginjection, as well as at 1 minute, 5 minutes, and 10 minutes after intubation, to capture theimmediate hemodynamic effects of the drugs and to observe any potential changes over timefollowing intubation.Results: The average age of the patients was 37.38±13.78 years. Out of 64 patients, 30(46.9%)were male and 34(53.1%) were female. Homodynamic effect was significantly high in thosepatients who received ketofol than those who received propofol (100% vs. 59.4% p=0.0005).The findings observed also with significant differences in hemodynamic effects between the twogroups, even after controlling for age, gender, and ASA classification (p-<0.05).Conclusion: Combination of Ketofol with ketofol was observed to be the betterhemodynamically as compared to Propofol. Additionally, the use of ketofol reduces the cost ofinduction and decreasing the economic burden on the patient.

A model with multiple intracranial aneurysms: possible hemodynamic mechanisms of aneurysmal initiation, rupture and recurrence

BackgroundHemodynamic factors play an important role in aneurysm initiation, growth, rupture, and recurrence, while the mechanism of the hemodynamic characteristics is still controversial. A unique model of multiple aneurysms (initiation, growth, rupture, and recurrence) is helpful to avoids the confounders and further explore the possible hemodynamic mechanisms of aneurysm in different states.MethodsWe present a model with multiple aneurysms, and including the states of initiation, growth, rupture, and recurrence, discuss the proposed mechanisms, and describe computational fluid dynamic model that was used to evaluate the likely hemodynamic effect of different states of the aneurysms.ResultsThe hemodynamic analysis suggests that high flow impingement and high WSS distribution at normal parent artery was found before aneurysmal initiation. The WSS distribution and flow velocity were decreased in the new sac after aneurysmal growth. Low WSS was the risk hemodynamic factor for aneurysmal rupture. High flow concentration region on the neck plane after coil embolization still marked in recanalized aneurysm.ConclusionsAssociations have been identified between high flow impingement and aneurysm recanalization, while low WSS is linked to the rupture of aneurysms. High flow concentration and high WSS distribution at normal artery associated with aneurysm initiation and growth, while after growth, the high-risk hemodynamics of aneurysm rupture was occurred, which is low WSS at aneurysm dome.

Nitric oxide donor increases umbilical vein blood flow and fetal oxygenation in fetal growth restriction. A pilot study

IntroductionTo evaluate the maternal and fetal hemodynamic effects of treatment with a nitric oxide donor and oral fluid in pregnancies complicated by fetal growth restriction. Methods30 normotensive participants with early fetal growth restriction were enrolled. 15 participants were treated until delivery with transdermal glyceryl trinitrate and oral fluid intake (Treated group), and 15 comprised the untreated group. All women underwent non-invasive assessment of fetal and maternal hemodynamics and repeat evaluation 2 weeks later. ResultsIn the treated group, maternal hemodynamics improved significantly after two weeks of therapy compared to untreated participants. Fetal hemodynamics in the treated group showed an increase in umbilical vein diameter by 18.87 % (p < 0.01), in umbilical vein blood flow by 48.16 % (p < 0.01) and in umbilical vein blood flow corrected for estimated fetal weight by 30.03 % (p < 0.01). In the untreated group, the characteristics of the umbilical vein were unchanged compared to baseline. At the same time, the cerebro-placental ratio increased in the treated group, while it was reduced in the untreated group, compared to baseline values. The treated group showed a higher birthweight centile (p = 0.03) and a lower preeclampsia rate (p = 0.04) compared to the untreated group. DiscussionThe combined therapeutic approach with nitric oxide donor and oral fluid intake in fetal growth restriction improves maternal hemodynamics, which becomes more hyperdynamic (volume-dominant). At the same time, in the fetal circuit, umbilical vein flow increased and fetal brain sparing improved. Although a modest sample size, there was less preeclampsia and a higher birthweight suggesting beneficial maternal and fetal characteristics of treatment.

Hemodynamic effects of withholding vs. continuing angiotensin II receptor blockers on the day of prone positioning spinal surgery in elderly patients.

The hemodynamic effects of withholding vs. continuing angiotensin II receptor blockers (ARBs) before surgery in elderly patients undergoing spinal surgery in a prone position during anesthesia induction to skin incision are still unknown. In this prospective study, 80 patients undergoing spinal surgery in a prone position with general anesthesia, aged 60-79 years, American Society of Anesthesiologists (ASA) II or III, were enrolled. Patients who had ARBs only in their preoperative medication list were randomly divided into two groups at a 1:1 ratio: In Group A, ARBs were continued on the morning of surgery, while in Group B, they were withhold. Norepinephrine was infused to maintain the blood pressure at the baseline level of ±20% during anesthesia induction in all patients. The primary outcome was the consumption of norepinephrine in each group from anesthesia induction to skin incision. The secondary outcomes include changes in invasive arterial blood pressure and heart rate, the fluid infusion volumes, the amounts of anesthetic drugs, and the total time from induction to skin incision. There were no significant differences in the demographics, the fluid infusion volumes, the amounts of anesthetic drugs, the total time from induction to skin incision, and hemodynamics at different time points (p > 0.05), while significant differences were found in norepinephrine consumption between the two groups (p < 0.001). Compared with Group B, the consumption of norepinephrine increased significantly in Group A (93.3 ± 29.8 vs. 124.1 ± 38.7 μg, p = 0.000). In addition, the same trend was illustrated in the pumping rate of norepinephrine between Group B (0.04 ± 0.01 μg·kg-1·min-1) and Group A (0.06 ± 0.02 μg·kg-1·min-1) (p = 0.004). Our study conducted in elderly patients with hypotension undergoing prone spinal surgery demonstrated a greater pumping rate of norepinephrine during anesthesia induction in patients with ARBs continuing before surgery than those withholding, indicating that it was more difficult to maintain hemodynamic stability.Clinical Trial Registration: https://www.chictr.org.cn/showproj.html?proj=141081, ChiCTR2100053583.

Assessing changes in regional cerebral hemodynamics in adults with a high-density full-head coverage time-resolved near-infrared spectroscopy device.

Cerebral oximeters have the potential to detect abnormal cerebral blood oxygenation to allow for early intervention. However, current commercial systems have two major limitations: (1)spatial coverage of only the frontal region, assuming that surgery-related hemodynamic effects are global and (2)susceptibility to extracerebral signal contamination inherent to continuous-wave near-infrared spectroscopy (NIRS). This work aimed to assess the feasibility of a high-density, time-resolved (tr) NIRS device (Kernel Flow) to monitor regional oxygenation changes across the cerebral cortex during surgery. The Flow system was assessed using two protocols. First, digital carotid compression was applied to healthy volunteers to cause a rapid oxygenation decrease across the ipsilateral hemisphere without affecting the contralateral side. Next, the system was used on patients undergoing shoulder surgery to provide continuous monitoring of cerebral oxygenation. In both protocols, the improved depth sensitivity of trNIRS was investigated by applying moment analysis. A dynamic wavelet filtering approach was also developed to remove observed temperature-induced signal drifts. In the first protocol ( years; five females, five males), hair significantly impacted regional sensitivity; however, the enhanced depth sensitivity of trNIRS was able to separate brain and scalp responses in the frontal region. Regional sensitivity was improved in the clinical study given the age-related reduction in hair density of the patients ( years; 14 females, 13 males). In five patients who received phenylephrine to treat hypotension, different scalp and brain oxygenation responses were apparent, although no regional differences were observed. The Kernel Flow has promise as an intraoperative neuromonitoring device. Although regional sensitivity was affected by hair color and density, enhanced depth sensitivity of trNIRS was able to resolve differences in scalp and brain oxygenation responses in both protocols.

Isoproterenol Improves Hemodynamics And Right Ventricle-Pulmonary Artery Coupling After Heart Transplantation.

Right ventricular failure (RVF) is a major cause of early mortality after heart transplantation (HT). Isoproterenol has chronotropic, inotropic, and vasodilatory properties which might improve right ventricle function in this setting. We aimed to investigate the hemodynamic effects of isoproterenol on patients with post-HT RVF. We conducted a one-year retrospective observational study including patients receiving isoproterenol and dobutamine for early RVF after HT. A comprehensive multiparametric hemodynamic evaluation was performed successively at three times: no isoproterenol, low doses: 0.025 µg/kg/min and high doses: 0.05 µg/kg/min (henceforth respectively called no-iso, low-iso and high-iso). From June 2022 to June 2023, 25 patients, median [IQR25-75] age 54 [38-61] years, were included. Before isoproterenol introduction, all patients received dobutamine and 15 (60%) were on veno-arterial extracorporeal membrane oxygenation. Isoproterenol significantly increased heart rate from 84 [77-99] (no-iso) to 91 [88-106] (low-iso) and 102 [90-122] bpm (high-iso, p<0.001). Similarly, cardiac index raised from 2.3 [1.4-3.1] to 2.7 [1.8-3.4] and 3 [1.9-3.7] l/min/m2 (p<0.001) with concomitant increase of indexed stroke volume (28 [17-34] to 31 [20-34] and 33 [23-35] mL/m2, p<0.05). Effective pulmonary arterial elastance and pressures were not modified by isoproterenol. Pulmonary vascular resistance tended to decrease from 2.9 (1.4-3.6) WU to 2.3 (1.3-3.5) WU, p=0.06. Right ventricular ejection fraction/systolic PAP evaluating RV-PA coupling increased after isoproterenol from 0.8 to 0.9 and 1 %.mmHg-1 (p=0.001). In post-HT RVF, isoproterenol exhibits chronotropic and inotropic effects, thereby improving RV-PA coupling and resulting in a clinically relevant increase in the cardiac index.

The Hemodynamic Effects of Interatrial Septostomy in Iatrogenic Mitral Stenosis Following MitraClip

The Hemodynamic Effects of Interatrial Septostomy in Iatrogenic Mitral Stenosis Following MitraClip

Comparative Study of Cardiovascular Effects of Selected Pulmonary Vasodilators in Canine Models of Mitral Valve Disease

Previous reports have shown that various oral pulmonary vasodilators are effective against canine pulmonary hypertension (PH). However, no studies have compared their hemodynamic effects. We aimed to compare the hemodynamic effects of 15 µg/kg beraprost sodium, 1.0 mg/kg sildenafil, and their combination, in dogs with experimentally induced mitral regurgitation. This experimental crossover study evaluated the hemodynamic and functional effects of oral pulmonary vasodilators by application of right-sided heart catheterization and echocardiography. Beraprost significantly decreased pulmonary and systemic vascular resistance. Additionally, beraprost increased right-ventricular stroke volume and left-ventricular cardiac output without worsening left-heart size and left-atrial pressure. The pulmonary vasodilatory effects of sildenafil were stronger, and its systemic vasodilatory effects were weaker than those of beraprost. However, sildenafil significantly increased the left-ventricular volume, left-atrial pressure indicator, and right-ventricular cardiac output. Combination therapy resulted in the strongest pulmonary and systemic vasodilating effects without worsening the left-heart size and left-atrial pressure indicators. Both beraprost and sildenafil were effective against canine PH; however, sildenafil was associated with the risk of worsening left-heart loading. Combination therapy with beraprost and sildenafil synergistically dilated pulmonary and systemic vessels, indicating a more potent treatment option for severe PH cases.

Cardiorenal Syndromes and Their Role in Water and Sodium Homeostasis

Sodium is the main osmotically active ion in the extracellular fluid and its concentration goes hand in hand with fluid volume. Under physiological conditions, homeostasis of sodium and thus amount of fluid is regulated by neural and humoral interconnection of body tissues and organs. Both heart and kidneys are crucial in maintaining volume status. Proper kidney function is necessary to excrete regulated amount of water and solutes and adequate heart function is inevitable to sustain renal perfusion pressure, oxygen supply etc. As these organs are bidirectionally interconnected, injury of one leads to dysfunction of another. This condition is known as cardiorenal syndrome. It is divided into five subtypes regarding timeframe and pathophysiology of the onset. Hemodynamic effects include congestion, decreased cardiac output, but also production of natriuretic peptides. Renal congestion and hypoperfusion leads to kidney injury and maladaptive activation of renin-angiotensin-aldosterone system and sympathetic nervous system. In cardiorenal syndromes sodium and water excretion is impaired leading to volume overload and far-reaching negative consequences, including higher morbidity and mortality of these patients. Keywords: Cardiorenal syndrome • Renocardiac syndrome • Volume overload • Sodium retention

Evaluating haemodynamic changes: vericiguat in patients with heart failure with reduced ejection fraction.

Vericiguat has been used to treat patients with heart failure with reduced ejection fraction (HFrEF) who demonstrated worsening heart failure despite treatment with other guideline-directed medical therapies. The haemodynamic effects of vericiguat remain unclear. This study enrolled 12 patients (median age, 63 [quartiles 53.5, 70] years; 16.7%(N=2) women) with symptomatic HFrEF (New York Heart Association functional class II-IV) who demonstrated worsening heart failure despite treatment with the four foundational guideline-recommended therapies between March and December 2022, with follow-ups completed in June 2023. A balloon-tipped pulmonary artery thermodilution catheter was placed in the right internal jugular vein to perform right heart catheterisation (RHC) on day 1. Haemodynamic data were acquired before and after vericiguat intake (2.5mg) on days 2 and 3. The data on days 2 and 3 were averaged. RHC was repeated on day 105 (37, 168). Oral intake of vericiguat 2.5mg decreased mean pulmonary artery pressure (19.3 [14.3, 26.8] mmHg) and pulmonary artery wedge pressure (PAWP) (11 [7.5, 15] mmHg) before the intake to mean pulmonary artery pressure (17.5 [12.5, 24] mmHg) and PAWP (9.3 [6.8, 14] mmHg) at 30min after (both P<0.05). Reduction in PAWP was also found from 14.5 [9.5, 19.5] mmHg on day 1 to 9.5 [6.5, 12.5] mmHg on day 105 (37, 168) (P<0.05), when vericiguat was titrated to 2.5mg 25% (N=3), 5mg 50% (N=6), and 10mg 25% (N=3). The consistent reduction in PAWP underscores the well-tolerated nature of vericiguat and its potential to enhance cardiac performance in patients with HFrEF.

A study of hemodynamic effects, postoperative recovery, and safety of esketamine (right handed) during flexible bronchoscopy under general anesthesia

Objective Flexible bronchoscopy during general anesthesia has become an indispensable tool. Anesthetics are widely utilized in flexible bronchoscopy (FB). This study delved into the application value of a subanesthetic dose of esketamine (ES) (right handed) in flexible bronchoscopy during general anesthesia. Methods A sample of 160 patients who underwent flexible bronchoscopy during general anesthesia were selected as study subjects and were equally divided into the control and ES groups, with clinical baseline data (age, sex, body mass index, American Society of Anesthesiologists grading) collected. Hemodynamic parameters (mean artery pressure, heart rate, pulse blood oxygen saturation) at different time points, the onset time of anesthesia, surgery time, analgesia maintenance time, anesthesia awakening time, and perioperative adverse reactions were recorded. Visual analogue scale (VAS), Mini-Mental State Examination (MMSE), and quality of recovery-40 (QoR-40) scales were utilized for assessing post-surgery satisfaction, cognitive function, and post-surgery early recovery quality. Results The hemodynamics were stable at each time point, but patients in the ES group were more stable than those in the control group. Patients in the ES group exhibited faster onset and awakening time of anesthesia, longer duration of analgesia, and lower total incidence of adverse reactions versus the control group. The patients’ QoR-40 total scores in the ES group were improved versus the control group at 1 day after surgery. Conclusion Compared with fentanyl, the use of ES (right handed) in flexible bronchoscopy during general anesthesia produces more stable hemodynamics, faster onset and recovery time of anesthesia, longer duration of analgesia, lower incidence of adverse reactions, and improved early postoperative recovery quality in patients.

Are We Always Right? Evaluation of the Performance and Knowledge of the Passive Leg Raise Test in Detecting Volume Responsiveness in Critical Care Patients: A National German Survey.

Background: In hemodynamically unstable patients, the passive leg raise (PLR) test is recommended for use as a self-fluid challenge for predicting preload responsiveness. However, to interpret the hemodynamic effects and reliability of the PLR, the method of performing it is of the utmost importance. Our aim was to determine the current practice of the correct application and interpretation of the PLR in intensive care patients. Methods: After ethical approval, we designed a cross-sectional online survey with a short user-friendly online questionnaire. Using a random sample of 1903 hospitals in Germany, 182 hospitals with different levels of care were invited via an email containing a link to the questionnaire. The online survey was conducted between December 2021 and January 2022. All critical care physicians from different medical disciplines were surveyed. We evaluated the correct points of concern for the PLR, including indication, contraindication, choice of initial position, how to interpret and apply the changes in cardiac output, and the limitations of the PLR. Results: A total of 292 respondents participated in the online survey, and 283/292 (97%) of the respondents completed the full survey. In addition, 132/283 (47%) were consultants and 119/283 (42%) worked at a university medical center. The question about the performance of the PLR was answered correctly by 72/283 (25%) of the participants. The limitations of the PLR, such as intra-abdominal hypertension, were correctly selected by 150/283 (53%) of the participants. The correct effect size (increase in stroke volume ≥ 10%) was correctly identified by 217/283 (77%) of the participants. Conclusions: Our results suggest a considerable disparity between the contemporary practice of the correct application and interpretation of the PLR and the practice recommendations from recently published data at German ICUs.

Randomised control trial comparing postoperative analgesia between nalbuphine and fentanyl as an adjuvant with intrathecal levobupivacaine for lower abdominal gynaecological surgeries

Background Effective post-operative pain management is crucial for patient comfort and recovery following lower abdominal gynaecological surgeries. This study protocol outlines a randomised control trial designed to compare the efficacy and safety of two intrathecal adjuvants, nalbuphine and fentanyl, in conjunction with hyperbaric levobupivacaine for postoperative analgesia. Methods The study will be conducted at the Department of Anaesthesiology, Jawaharlal Nehru Medical College, DMIMS (DU), and affiliated institutions. Sixty eligible patients aged 35-75 years undergoing lower abdominal gynaecological surgeries under subarachnoid block will be randomly assigned to one of two groups. Group A will receive nalbuphine with levobupivacaine, while Group B will receive fentanyl with levobupivacaine. Patients will be monitored for the duration of post-operative analgesia, onset of sensory and motor block, hemodynamic effects, and side effects. Outcomes The primary outcome is the comparison of post-operative analgesia duration between nalbuphine and fentanyl. Secondary outcomes include assessing sensory and motor block onset, hemodynamic changes, ephedrine usage, and side effects. Aim To evaluate the efficacy and safety of intrathecal nalbuphine and fentanyl as adjuvants with hyperbaric levobupivacaine for postoperative analgesia in lower abdominal gynaecological surgeries.

Therapeutic potential of conduction system pacing as a method for improving cardiac output during ventricular tachycardia.

Ventricular tachycardia (VT) reduces cardiac output through high heart rates, loss of atrioventricular synchrony, and loss of ventricular synchrony. We studied the contribution of each mechanism and explored the potential therapeutic utility of His bundle pacing to improve cardiac output during VT. Study 1 aimed to improve the understanding of mechanisms of harm during VT (using pacing simulated VT). In 23 patients with left ventricular impairment, we recorded continuous ECG and beat-by-beat blood pressure measurements. We assessed the hemodynamic impact of heart rate and restoration of atrial and biventricular synchrony. Study 2 investigated novel pacing interventions during clinical VT by evaluating the hemodynamic effects of His bundle pacing at 5bpm above the VT rate in 10 patients. In Study 1, at progressively higher rates of simulated VT, systolic blood pressure declined: at rates of 125, 160, and 190bpm, -22.2%, -42.0%, and -58.7%, respectively (ANOVA p < 0.0001). Restoring atrial synchrony alone had only a modest beneficial effect on systolic blood pressure (+ 3.6% at 160bpm, p = 0.2117), restoring biventricular synchrony alone had a greater effect (+ 9.1% at 160bpm, p = 0.242), and simultaneously restoring both significantly increased systolic blood pressure (+ 31.6% at 160bpm, p = 0.0003). In Study 2, the mean rate of clinical VT was 143 ± 21bpm. His bundle pacing increased systolic blood pressure by + 14.2% (p = 0.0023). In 6 of 10 patients, VT terminated with His bundle pacing. Restoring atrial and biventricular synchrony improved hemodynamic function in simulated and clinical VT. Conduction system pacing could improve VT tolerability and treatment.