Adverse Hemodynamic Effects Research Articles

In Vitro Analysis of Left Ventricular Assist Device Outflow Graft Orientations and Their Effect on Aortic Hemodynamics.

Continuous-flow left ventricular assist devices have become an important treatment option for patients with advanced heart failure. However, adverse hemodynamic effects as consequence of an altered blood flow within the aorta and the aortic root remain a topic of concern. In this work, we investigated the influence of the outflow graft orientation on the hemodynamic profile and flow parameters within the thoracic aorta. Aortic models with different outflow graft orientations were designed and three-dimensional (3D) printed to mimic common implantation configurations and were integrated into a pulsatile mock circulatory flow loop. Assist device function was achieved using a rotary pump, replicating nonpulsatile, continuous support flows of 1-5 L/min. Flow velocity, wall shear stress, and pressure gradients were investigated for each configuration using sonography and four-dimensional (4D) flow magnetic resonance imaging. Mean wall shear stresses measured in 4D flow software were lowest for a graft inclination angle of 45°. Streamline visualization revealed areas of nonuniform, retrograde, and vortex flow in all models but most prominent for the aortic model with an outflow graft inclination of 60°. The insights gained from this research may aid in understanding clinical outcomes following assist device implantation and long-term mechanical circulatory support.

CFD Investigation of Mechanical Heart Valve Orientations in Modulating Left Ventricular Hemodynamics

This study provides a comprehensive computational analysis of how mechanical heart valve orientations impact left ventricular (LV) hemodynamics, with potential implications for surgical valve placement. Focusing on monoleaflet valves (MLV) and bileaflet valves (BLV), the research explores how different valve angles influence blood flow patterns within the LV chamber. The analysis includes velocity contours, streamline patterns, vorticity contours, and temporal velocity fluctuations to elucidate the effects of valve orientation on LV performance. Findings indicate that valve orientation significantly influences flow coherence and blood velocity. For instance, a 20-degree orientation in the MLV alters jet flow in ways that could affect wall shear stress distribution. At a 45-degree angle, the MLV produces a more centralized jet flow, enhancing flow uniformity and aligning more closely with physiological conditions. In contrast, a 55-degree angle skews the jet flow, potentially leading to adverse hemodynamic effects. Similarly, BLV orientations at 45, 55, 60, and 70 degrees showed that lower angles improved flow efficiency, reducing energy losses and minimizing the risk of regurgitation, while higher angles led to turbulent and potentially damaging flow patterns. Comparative results at a 45-degree orientation demonstrated the superior performance of BLV in regulating normal velocity, with BLV reducing average blood velocity by 38.77% compared to a 29.53% reduction with MLV. These results underscore the importance of optimizing mechanical heart valve orientations to enhance left ventricular hemodynamics. The findings carry significant clinical implications, supporting evidence-based valve placement decisions that can substantially improve patient outcomes, survival rates and long-term cardiovascular health.

Effect of remimazolam on oxygen reserve compared with propofol during upper gastrointestinal endoscopy: Randomized controlled study.

Propofol is commonly used for endoscopic sedation. However, it can induce adverse hemodynamic effects. Remimazolam is known to have a fast onset and short duration comparable to that of propofol, but with fewer effects on hemodynamics. We assessed the Oxygen Reserve Index to verify whether a sedative dose of remimazolam would better preserve oxygenation in the mild hyperoxic range than propofol in sedated patients undergoing diagnostic upper gastrointestinal endoscopy. Patients scheduled for diagnostic upper gastrointestinal endoscopy were enrolled. Patients were randomly assigned to either the remimazolam or propofol groups and received 0.1 mg/kg remimazolam or 0.5 mg/kg propofol, respectively. Bolus injections of either 0.05 mg/kg remimazolam or 0.25 mg/kg propofol were added if required. The primary outcome was the prevalence of oxygen reserve depletion, defined as the Oxygen Reserve Index decreasing to 0.00, and hypoxia defined as peripheral oxygen saturation falling to <94%. Among 69 patients, the incidence of oxygen reserve depletion was significantly higher in the propofol group (65.7% vs. 38.2%, P = 0.022). Hypoxia was frequently observed in the propofol group, whereas none was observed in the remimazolam group (11.4% vs. 0%, P = 0.042). Additional sedative injections were frequently required to complete endoscopy in the propofol group. None of the patients in the remimazolam group required airway interventions. Nausea was frequent in the propofol group in the recovery room. Our results indicate that remimazolam is a safe and useful sedative for upper gastrointestinal endoscopy.

Analysis of the Ultrasensitive C-Reactive Protein and Homocysteine Biomarkers after Photobiomodulation Therapy in Hormone Blocker-Treated Mastectomized Women: A Randomized, Blind, and Controlled Clinical Study.

Main: The pharmacological treatment of cancer can lead to undesirable hemodynamic adverse effects. Laser therapy may promote hemodynamic balance in these patients. This study aimed to analyze the values of the biomarkers ultrasensitive C-reactive protein (PCR_us) and Homocysteine (HCy) after the use of intravascular laser irradiation of blood (ILIB) in mastectomized patients using hormonal blockers Tamoxifen and Aromatase Inhibitors. Methods: This was an experimental, placebo-controlled, randomized clinical trial with experimental (G1) and control (G2) groups. In G1, patients were irradiated with ILIB using a red laser at 660 nm on the carotid artery, while G2 received a placebo treatment. Blood collection for HCy and us-CRP biomarker evaluation was conducted monthly for 4 months. Statistical analysis was performed using R Studio 4.4.2 and JAMOVI, with a significance level of 5%. Results: A total of 21 patients participated in the study, with 12 in G1 and 9 in G2. There were no differences in age, systolic, diastolic blood pressure, and heart rate between the groups. The initial and final mean PCR_us levels for G1 were 6.8 and 3.8 mg/dL, and for HCy were 14.2 and 12.1 µmol/L, respectively. While for G2 initial and final mean PCR_us levels were 9.40 and 7.60 mg/dL, and for HCy were 14.33 and 16.69 µmol/L. There was no statistical difference for PCR_us. However, a significant difference between the groups (p < 0.05) for HCy in the 3rd and 4th months. Conclusion: During ILIB Therapy, there was a reduction in HCy, which may favor the improvement of cardiovascular function in these patients undergoing anticancer therapies.

Emergency Endotracheal Intubations at a Pediatric Intensive Care Unit—Incidence and Hemodynamic Complications

AbstractEmergency tracheal intubation (TI) in a critically ill child is a life-saving, high-risk procedure often associated with adverse events and complications. Efforts have been undertaken to increase the safety of TIs. Integrated checklists, simulation-based training, and video laryngoscope-assisted intubations have proven effective. The study's primary aim was to evaluate the frequency of emergency TIs at a pediatric intensive care unit (PICU) and to examine the incidence of peri-intubation hemodynamic complications. We conducted a single-center, retrospective analysis of unplanned (nonelective and emergency) intubations in a multidisciplinary PICU. Patients between 0 and 18 years admitted from January 2020 until December 2022 were included in the analysis. There was a total of 144 emergency TIs. In 92.6% of the cases, an underlying chronic disease existed. The most common indication for emergency TI was respiratory failure (61.0%). Adverse intubation-associated hemodynamic events were found in 18 (12.5%), cardiac arrest in 6 (4.2%), and emergency TI under ongoing cardiopulmonary resuscitation (CPR) in 12 (8.3%) cases. Twenty-two (15.3%) children died during the PICU stay after emergency TI due to the underlying condition. In the group of children showing adverse hemodynamic effects after TI, fewer children were on noninvasive respiratory support (50 vs. 75.2%, p = 0.007) and received catecholamine therapy more frequently before complicated emergency TI than those without complicated emergency TI (62.5 vs. 38.0%, p = 0.039). Children in the latter group had both a longer duration of mechanical ventilation (11 vs. 7 days, p = 0.045) and a longer PICU stay (18 vs. 12 days, p = 0.042) compared with the group of complicated emergency TIs. Most emergency TIs (59.0%) occurred off-hours, between 7 p.m. and 7 a.m., or on weekends. Emergency TIs occur unexpectedly, often outside regular operating hours, and are associated with a higher mortality and morbidity rate. Using noninvasive respiratory support could potentially reduce adverse intubation-associated hemodynamic events in emergency TI.

Assessment of effect of two different doses of dexmedetomidine infusion on emergence agitation and quality of recovery after nasal surgery

: To evaluate two different doses of dexmedetomidine infusion on emergence agitation and measurement of hemodynamics, bispectral index, cortisol levels, and quality of recovery in patients who underwent nasal surgery under general anaesthesia.94 individuals of either sex between the ages of 18 and 65 who experienced nasal surgery under general anesthesia were split into two groups for this randomized experimental study. Before induction, each group received loading doses of dexmedetomidine (DEX) infusion at a rate of 1 µg/kg over a period of 10 minutes. Group B underwent a standard induction and then received an infusion of 0.4μg/kg/h of dexmedetomidine every hour until they were extubated, while group A received an infusion of 0.8μg/kg/h. Sevoflurane was employed for maintenance. During emergence, the frequency of agitation, cough hemodynamic parameters, and recovery traits were assessed. Patients received the Quality of Recovery (QoR-40) questionnaire 24 hours following surgery.The hemodynamic reaction to laryngoscopy and intubation was blunted and the intubating circumstances were improved by both doses equally well. Group A's intraoperative mean PR and MAP were significantly (P&amp;#60;0.05) lower than group B's. Coughing was more common among the subjects in group A. A statistically significant difference was found between groups in comparing emergence agitation. Cortisol levels were significantly higher postoperatively in the 0.4µg/kg dose of dexmedetomidine 0.8µg/kg/ group (p=0.001). Global QoR-40 score at 24 h after surgery showed a better global recovery profile in group A. :Although a greater dose of DEX may have more hemodynamic adverse effects, it may also reduce the incidence of emergent agitation, the surgical stress response, and a smoother recovery profile.

Early Intravenous Beta-Blockade with Esmolol in Adults with Severe Traumatic Brain Injury: A Phase 2a Intervention Design Study

BackgroundTargeted beta-blockade after severe traumatic brain injury may reduce secondary brain injury by attenuating the sympathoadrenal response. The potential role and optimal dosage for esmolol, a selective, short-acting, titratable beta-1 beta-blocker, as a safe, putative early therapy after major traumatic brain injury has not been assessed.MethodsWe conducted a single-center, open-label dose-finding study using an adaptive model-based design. Adults (18 years or older) with severe traumatic brain injury and intracranial pressure monitoring received esmolol within 24 h of injury to reduce their heart rate by 15% from baseline of the preceding 4 h while ensuring cerebral perfusion pressure was maintained above 60 mm Hg. In cohorts of three, the starting dosage and dosage increments were escalated according to a prespecified plan in the absence of dose-limiting toxicity. Dose-limiting toxicity was defined as failure to maintain cerebral perfusion pressure, triggering cessation of esmolol infusion. The primary outcome was the maximum tolerated dosage schedule of esmolol, defined as that associated with less than 10% probability of dose-limiting toxicity. Secondary outcomes include 6-month mortality and 6-month extended Glasgow Outcome Scale score.ResultsSixteen patients (6 [37.5%] female patients; mean age 36 years [standard deviation 13 years]) with a median Glasgow Coma Scale score of 6.5 (interquartile range 5–7) received esmolol. The optimal starting dosage of esmolol was 10 μg/kg/min, with increments every 30 min of 5 μg/kg/min, as it was the highest dosage with less than 10% estimated probability of dose-limiting toxicity (7%). All-cause mortality was 12.5% at 6 months (corresponding to a standardized mortality ratio of 0.63). One dose-limiting toxicity event and no serious adverse hemodynamic effects were seen.ConclusionsEsmolol administration, titrated to a heart rate reduction of 15%, is feasible within 24 h of severe traumatic brain injury. The probability of dose-limiting toxicity requiring withdrawal of esmolol when using the optimized schedule is low.Trial registrationI SRCTN, ISRCTN11038397, registered retrospectively January 7, 2021 (https://www.isrctn.com/ISRCTN11038397).

Acute hemodynamic effects of the Marshall-Plan ablation on left and right atrial pressure: does 'respecting atrial physiology' prevent stiff left atria? A retrospective single- center analysis

Abstract Introduction Stiff left atrium (STILA)-syndrome is a relevant concern after extensive ablation in the left atrium (LA) e.g. in persistent atrial fibrillation (AF). STILA often causes disabling heart failure symptoms worse than the initial arrhythmia symptoms. Therefore preventing adverse ablation-induced hemodynamic effects is of utmost concern. Methods This single-center study retrospectively analyzed data from 89 consecutive patients who underwent biatrial ablation for AF following the Marshall-Plan between February 2022 and November 2023. The procedures included ablation of the CTI and PVI where necessary followed by ablation of a LA roof line and ablation of the lateral mitral isthmus after previously performed ethanol ablation of the vein of Marshall. This lesion set is considered to maintain physiological activation of the LA. This study evaluates acute hemodynamic changes following the Marshall-Plan. Invasive hemodynamic measurements of mean left and right atrial pressure, as well as A- and V-waves were performed in all patients before and after the ablation. We assessed the acute changes of atrial hemodynamics in these procedures. Continuous data are given as mean ± standard deviation, categorical data are expressed as number and percentages. Differences between groups were determined by Student’s t-test, chisquare-test, and Fisher’s exact test using SPSS software. A p-value of &amp;lt;0.05 was deemed significant. Results The patients' mean age was 70.1 ± 7.5 years and 39.0% were female. Mean BMI was 28.9 ± 5.2 kg/m². Procedures were performed under general anesthesia (with a PEEP of 5.5cmH2O (2-10 cmH2O)) and took 181 minutes on average. Left atrial mean pressure averaged at 15.7mmHg before the procedure. The overall average change of left atrial mean pressure was +1,8mmHg. The average change in left atrial A- and V-Wave amounted to -1.9mmHg and -0.9mmHg respectively. The pre-procedural average right atrial mean pressure was 12.1mmHg. Right atrial mean pressure inclined by +1.6mmHg. The average change in right atrial A- and V-Wave was +0.6mmHg and +1.1mmHg respectively. The i.v. administered volume averaged 1900 ± 285ml. 3.3% of patients showed an increase of mean LA-pressure &amp;gt;9mmHg. Those patients tended to be older (74.3years), were all male (100%) and had a higher BMI (31.5 kg/m²) as well as higher amount of i.v. administered volume (2333ml) and a longer procedure (213min). Discussion Complex and extensive biatrial ablation following the Marshall-Plan does not lead to acute significant increases in left or right atrial pressures. The administered i.v. volume might explain the slight increases observed. In our observation, the rate of significant increases in LA-pressure is low. This suggests that disrupting the (left) atrial activation pattern might play a role in the development of diastolic dysfunction and thereby STILA-syndrome. Respecting atrial physiology may be beneficial for preventing adverse hemodyamic changes after ablation.

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.

The effect of NHFOV on hemodynamics in mild and moderately preterm neonates: a randomized clinical trial

The aim of this study is to study cardio-respiratory effects of nasal high-frequency oscillatory ventilation (NHFOV) vs. NCPAP as an initial mode of ventilation in moderate-late-preterm infants. A randomized controlled trial was conducted in NICU of Alexandria University Maternity Hospital (AUMH). One-hundred late-moderate-preterm infants were randomly assigned to either NHFOV-group (n = 50) or NCPAP-group (n = 50). For both groups, functional echocardiography was performed in the first 24 h to detect hemodynamic changes and respiratory outcome was monitored throughout the hospital stay. The main outcomes were hemodynamic measurements and myocardial function using functional echocardiography of those infants along with the respiratory outcome and complications. Kaplan–Meier survival plot was used representing time course of NCPAP and NHFOV failure. Left ventricular output values were not significantly different in both groups with median 202 ml/kg /min and IQR (176–275) in NCPAP-group and 226 ml/kg/min with IQR (181–286) in NHFOV group. Nevertheless, ejection fraction and fractional shortening were significantly higher in NHFOV-group with P 0.001. The time to weaning, the time to reach 30%-FIO2, the need for invasive ventilation, oxygen support duration, and maximal-FIO2 were significantly more in NCAPAP group. Conclusion: NHFOV is an effective and promising tool of non-invasive-ventilation which can be used as a primary modality of respiratory support in preterm infants with variable forms of respiratory distress syndrome without causing detrimental effect on hemodynamics or significant respiratory complications. Trial registration: NCT05706428 (registered on January 21, 2023).What is Known:• NHFOV might be beneficial as a secondary mode of ventilation and might have an impact on hemodynamics.What is New:• NHFOV can be used as an initial mode of ventilation with CDP beyond the reported pressure limits of CPAP without causing neither CO2 retention nor adverse hemodynamic consequences.

Comparison of Hemodynamic Effects of Dose Response vs. Conventional Dosing of Propofol for Anesthesia Induction Under Bispectral Index Monitoring: A Clinical Trial

Propofol is an advantageous agent for anesthesia induction. It can cause dose-related hemodynamic adverse effects. The bispectral index (BIS) is a brain function monitor utilized to assess the depth of anesthesia. This study aimed to compare the adverse hemodynamic effects of BIS-guided response dosing with conventional weight-based dosing of Propofol. In this clinical trial, patients were anesthetized with propofol in two different orthopedic operating rooms. In one operating room, patients received propofol with dose-response method (group A), and the other received weight-based dosing (group B). For both groups, BIS was used as an index of anesthesia depth. Hemodynamic parameters were recorded at baseline, during induction, and at different time points. A total of 73 patients were included in the final analysis. The mean dose of propofol for induction was higher in the control group than in the response-guided group (1.94±1.65 vs. 1.09±0.32, respectively, P=0.006). There were no reported significant adverse hemodynamic effects in patients of the two groups. Response-guided propofol dosing can be used to decrease propofol dose during anesthesia induction. Further studies are needed to investigate the clinical benefit of this dosing strategy.

Left atrial appendage occlusion: Percutaneous and surgical approaches in everyday practice.

Prophylactic left atrial appendage occlusion has been suggested as a means of reducing cardioembolism risk in patients with atrial fibrillation. Its clinical benefits have been discussed together with potential endocrine or hemodynamic adverse effects, with conflicting conclusions. We aimed to provide a thorough overview of the current literature and a recommendation for daily clinical decision-making. A comprehensive Medline search through PubMed was conducted to search for relevant articles, which were further filtered using the title and abstract. Sixty-five articles were selected as relevant to the topic. Concomitant left atrial appendage occlusion during cardiac surgery for other reasons is effective in terms of thromboembolism risk reduction in patients with a history of atrial fibrillation and higher CHA2DS2-VASc scores. Surgical occlusion is safe, and epicardial closure techniques are preferred. Thoracoscopic and transcatheter techniques are also feasible, and the individual treatment choice must be tailored to the patient. The concerns about endocrine imbalance or risk of heart failure after occlusion are not supported by evidence. Current evidence is conflicting with regard to hemodynamic consequences of appendage occlusion.

Transdermal Nicotine Patch Increases the Number and Function of Endothelial Progenitor Cells in Young Healthy Nonsmokers without Adverse Hemodynamic Effects.

Transdermal nicotine patches (TNPs), administering nicotine into the bloodstream through skin, have been widely used as nicotine replacement therapy, and exposure to nicotine can be detected by measurement of plasma cotinine concentration. In animal studies, nicotine treatment could increase the number of endothelial progenitor cells (EPCs), but the effect of TNPs on circulating EPCs and their activity in humans remained unclear. This study aimed to explore the influence of TNPs on circulating EPCs with surface markers of CD34, CD133, and/or KDR, and colony-forming function plus migration activity of early EPCs derived from cultured peripheral blood mononuclear cells before and after TNP treatments in young healthy nonsmokers. In parallel, pulse wave analysis (PWA) was applied to evaluate the vascular effect of TNP treatments. Twenty-one participants (25.8 ± 3.6 years old, 10 males) used TNP (nicotine: 4.2 mg/day) for 7 consecutive days. During the treatment, the CD34+ EPCs progressively increased in number. In addition, the number of EPCs positive for CD34/KDR, CD133, and CD34/CD133 were also increased on day 7 of the treatment. Furthermore, the early EPC colony-forming function and migration activity were increased with the plasma cotinine level positively correlating with change in colony-forming unit number. PWA analyses on day 7, compared with pretreatment, did not show significant change except diastolic pressure time index, which was prolonged and implied potential vascular benefit. In conclusion, 7-day TNP treatments could be a practical strategy to enhance angiogenesis of circulating EPCs to alleviate tissue ischemia without any hemodynamic concern.

Retrospective Analysis of Perioperative Dexmedetomidine Use in Retina Surgeries: Impact on Postanesthesia Care.

Dexmedetomidine (Precedex®) has been linked to depressive hemodynamic effects and increased length of stay in the post-anesthesia care unit (PACU) when used in ambulatory phacoemulsification procedures. We aimed to determine the prevalence and impact of dexmedetomidine use during ambulatory vitreoretinal procedures. This retrospective cohort study involved 9,666 adult vitrectomies. Cases were divided into groups by anesthesia type: general anesthesia (GA) and monitored anesthesia care (MAC). For each group, various factors were compared between those who did and did not receive dexmedetomidine. Chi-squared and t tests were used for comparisons. Changes in mean arterial pressure in the MAC group were -1.69 ± 0.23 mmHg for no dexmedetomidine patients and -6.31 ± 0.39 mmHg for dexmedetomidine patients (P < 0.01). In the GA group, mean arterial pressure was -6.1 ± 0.35 mmHg for no dexmedetomidine patients and -11.18 ± 0.88 mmHg for dexmedetomidine patients (P < 0.01). PACU Phase II time in the MAC group was 36.93 ± 0.37 minutes and 40.67 ± 0.86 minutes for no dexmedetomidine and dexmedetomidine patients, respectively (P < 0.01). In the GA group, PACU Phase II time was 58.63 ± 0.95 minutes and 65.19 ± 2.38 minutes for no dexmedetomidine and dexmedetomidine patients, respectively (P < 0.01). Dexmedetomidine use in vitrectomies was associated with significant PACU delays. These delays may stem from adverse hemodynamic effects. [Ophthalmic Surg Lasers Imaging Retina 2024;55:86-91.].

Preliminary Experience With Remimazolam for Procedural Sedation and as an Adjunct to General Anesthesia During Diagnostic and Interventional Cardiac Procedures.

Remimazolam is a benzodiazepine which, like midazolam, has sedative, anxiolytic, and amnestic properties. Ester metabolism results in a half-life of 5 - 10 min, a limited context sensitive half-life, and rapid recovery when the infusion is discontinued. Following the Institutional Review Board (IRB) approval, we performed a retrospective chart review of patients who received remimazolam in the cardiac catheterization, cardiac magnetic resonance imaging (MRI), and electrophysiology suites. The primary objective was to assess efficacy and safety. The secondary objective was to describe bolus and infusion dosing of remimazolam and the need for adjunctive agents to optimize procedural sedation conditions. The study cohort included 26 patients with a median age of 18 years and a total of 33 anesthetic encounters. The most common procedures were endomyocardial biopsy or isolated hemodynamic assessment (right or left heart catheterization). Remimazolam was the primary agent for sedation in 82% of the procedures. The majority of cases (25 encounters, 76%) included a bolus dose of remimazolam prior to the start of an infusion. For those patients who received a starting bolus dose, dosing typically ranged between 30 and 110 µg/kg. Continuous infusion rates of remimazolam varied from 5 to 20 µg/kg/min. No adverse hemodynamic or respiratory effects were noted. Midazolam, fentanyl, and dexmedetomidine were the most frequently used adjunctive agents. One patient required transition to general anesthesia due to the need for a surgical intervention based on the findings of the cardiac catheterization. All other patients were effectively sedated. Our preliminary experience demonstrates that remimazolam effectively provided sedation for diagnostic and therapeutic cardiovascular procedures. Future studies are needed to further define dosing parameters for both bolus dosing and continuous infusion as well as to compare remimazolam to other commonly used for procedural sedation in patients with congenital and acquired heart disease.

Evaluation of efficacy of low dose IV ketamine for prevention of pain associated with IV propofol injection

Propofol is a widely used intravenous anaesthetic that is known to cause distressing local pain at the site of injection. Ketamine pretreatment is one of the methods proposed to attenuate Propofol injection pain due to its local anaesthetic properties.The present study was undertaken to evaluate the efficacy of low dose (100 mcg/kg) I.V. Ketamine in decreasing I.V. Propofol injection pain by using McCrirrick and Hunter scale.72 adult patients of ASA Physical status 1 and 2 of either sex undergoing elective surgical procedure under general anaesthesia were randomly allocated into two groups.Group- A (n=36): Pre-treatment with Ketamine 100µg/kg (1ml) and Group- B (n=36): pre-treatment with 0.9% Normal Saline (1ml).Comparison between group A and group B using McCrirrick and Hunter Evaluation Scale at 5,10 and 15 seconds intervals were statistically highly significant (p value&amp;#60;0.0001). None of the patients in group A experienced moderate or severe pain at all 3 intervals as compared to group B. McCrirrick and Hunter evaluation score mean values were also highly significant at all time intervals between both the groups. Hemodynamic parameters, EtCO and SpO were comparable between two groups. There was no incidence of any adverse effects in both the groups. I.V. Ketamine in a dose of 100mcg/kg with tourniquet as pretreatment before Propofol was useful in significantly reducing the incidence and severity of pain without any adverse haemodynamic effect.

The Limited Use Of Dexmedetomidine For Subarachnoid Blocks In Pakistan.

Respected Madam, Dexmedetomidine is a selective alpha-2 adrenoceptor agonist. It acts by binding to the presynaptic alpha-2 adrenoceptors and inhibits the release of norepinephrine. Thereafter, it causes a decrease in the sympathetic tone and terminates the propagation of pain signals. As a result, the haemodynamic and the endocrine stress responses of the body to surgery and anesthesia are attenuated, the blood pressure and heart rate are decreased, and the requirement for other anaesthetic agents is reduced. These effects have meant that dexmedetomidine has been widely used prior to endotracheal intubation to optimize the patients and prevent the likelihood of hemodynamic adverse effects (1). In addition to its use in general anesthesia, peri-operative physicians worldwide are now becoming increasingly aware of the dexmedetomidine’s potential usefor subarachnoid blocks. A few studies have documented the efficacy of intravenous (IV) dexmedetomidine in prolonging the duration of sensory and motor blockade induced by agents such as bupivacaine, prilocaine, and ropivacaine up to 4 hours (2), (3). Recent studies have found that intrathecal administration of dexmedetomidine in combination with the local anesthetic agent yields similar benefits (4). This has been attributed to the activation of presynaptic alpha2-A receptors at locus ceruleus and the termination of pain signal propagation via the medullospinal noradrenergic pathway (4). Therefore, it is no surprise that the use of dexmedetomidine in conjunction with local anesthetics for the subarachnoid block is common practice in peri-operative physicians throughout the globe. While Pakistani peri-operative physicians are aware of the benefits of dexmedetomidine prior to endotracheal intubation (5), the same cannot be said for subarachnoid blocks induced in Pakistan. Peri-operative physicians in Pakistan are either yet to realize the potential benefits the use of dexmedetomidine can provide for subarachnoid blocks or still adhere to conventional spinal anesthesia practices. Since the effects of a conventional subarachnoid block last from 2 to 3 hours, in any case of a surgical adverse event that prolongs the surgery, severe pain, nausea, vomiting, and derangement of the hemodynamic status have been noted in patients. Often times, this results in a shift towards general anesthesia midway through the procedure. Ultimately, the postoperative stay is prolonged which directly impacts the clinical outcome and the quality of life for these patients. ---Continue

Haemodynamic effects of methoxyflurane versus fentanyl and placebo in hypovolaemia: a randomised, double-blind crossover study in healthy volunteers

BackgroundMethoxyflurane is approved for relief of moderate to severe pain in conscious adult trauma patients: it may be self-administrated and is well suited for use in austere environments. Trauma patients may sustain injuries causing occult haemorrhage compromising haemodynamic stability, and it is therefore important to elucidate whether methoxyflurane may adversely affect the haemodynamic response to hypovolaemia. MethodsIn this randomised, double-blinded, placebo-controlled, three-period crossover study, inhaled methoxyflurane 3 ml, i.v. fentanyl 25 μg, and placebo were administered to 15 healthy volunteers exposed to experimental hypovolaemia in the lower body negative pressure model. The primary endpoint was the effect of treatment on changes in cardiac output, while secondary endpoints were changes in stroke volume and mean arterial pressure and time to haemodynamic decompensation during lower body negative pressure. ResultsThere were no statistically significant effects of treatment on the changes in cardiac output, stroke volume, or mean arterial pressure during lower body negative pressure. The time to decompensation was longer for methoxyflurane compared with fentanyl (hazard ratio 1.9; 95% confidence interval 0.4–3.4; P=0.010), whereas there was no significant difference to placebo (hazard ratio −1.3; 95% confidence interval −2.8 to 0.23; P=0.117). ConclusionsThe present study does not indicate that methoxyflurane has significant adverse haemodynamic effects in conscious adults experiencing hypovolaemia. Clinical trial registrationClinicalTrials.gov (NCT04641949) and EudraCT (2019-004144-29) https://www.clinicaltrialsregister.eu/ctr-search/trial/2019-004144-29/NO.

Left-to-right atrioventricular activation delay, a novel measure of AV-conduction, predicts clinical outcomes in non-LBBB patients

Abstract Funding Acknowledgements Type of funding sources: None. Background The PR-interval reflects atrial and atrioventricular activation. A prolonged PR has been linked to heart failure (HF), atrial fibrillation and mortality. This might at least in part be the consequence of compromised cardiac performance (e.g. left ventricular filling). On the other hand, very long PR may just be a marker of advanced heart disease. Alternative measures that account for atrial and ventricular activation might better predict adverse hemodynamic consequences of delayed atrioventricular conduction. The DEEPER-PR mechanistic pilot study suggested that various novel measures of AV conduction are associated with Doppler-derived cardiac performance. However, the clinical significance of these novel parameters is unknown. Study objective: To examine the association of novel measures of AV conduction with clinical outcomes in a HFrEF population with non-LBBB and a wide QRS (non-LBBB ICD-only MADIT-CRT subset). Methods Time intervals from anonymized scanned baseline 12-lead ECGs from the Multicenter Automatic Defibrillator Implantation Trial – Cardiac Resynchronization Therapy (MADIT-CRT), non-LBBB patients (n=537) were assessed in detail using ImageJ (public domain software provided by NIH). The primary endpoint of the study was the combined endpoint of heart failure (HF) or death events. The earliest onset of atrial activation (P wave onset), zero crossing of the P wave in lead V1, earliest onset of the QRS complex, time interval to the first peak of the R wave in V1 and V6, and QRS width were determined. The PR interval and 8 novel parameters (see figure 1) were measured and calculated accordingly. Bivariate non-parametric correlations were calculated to ascertain the associations between these covariates. In addition, Kaplan-Meier analyses by quintiles of all AV delay measures, and multivariable Cox regression analyses were performed among ICD-only patients (n=209) to determine the associated risk regarding of the combined MADIT-CRT clinical outcome of HF events or death. Results Weak correlations were found between the AV delay variables (figure 2). Four of the variables (P0PV1, P0R, PePV6, PR) were significantly associated to the risk of HF or death with the upper quintile defining a high-risk HF population, as compared to quintiles 1 to 4 (see figure 3). This indicated a threshold behavior of the associations. P0PV1 was the most powerful risk predictor (Chi-square=16.31, HR for Q5 vs. Q1-4=3.12, CI=1.80-5.41, p&amp;lt;0.001), followed by PRmax (Chi-square=13.19, HR for Q5 vs. Q1-4=2.81, CI=1.61-4.92, p&amp;lt;0.001), P0R (Chi-square=10.42, HR=2.54, CI=1.44-4.48, p=0.001), and PePV6 (Chi-square=7.96, HR for Q5 vs. Q1-4=2.2, CI=1.29-4.07, p=0.005). Conclusion This post-hoc ECG-based study identified in MADIT-CRT non-LBBB patients the left-to-right atrioventricular activation delay (P0PV1) as the most powerful risk predictor of HF or death. Prospective evaluation of this measure is warranted.

An explorative analysis of pharmacovigilance data of oxytocin and its analogue carbetocin, with a focus on haemodynamic adverse effects

BackgroundOxytocin and its analogue carbetocin are uterotonics whose prophylactic use is recommended to prevent postpartum haemorrhage, which is one of the leading causes of maternal deaths worldwide. However, both drugs can cause specific adverse effects and haemodynamic challenges.AimThe aim of this work was to exploratively examine reports of adverse drug events of both drugs and to establish a comparative haemodynamic profile.MethodUsing data extracted from the World Health Organization’s pharmacovigilance database VigiBase, a descriptive analysis was performed of all reports for oxytocin and carbetocin as a suspected or interacting drug followed by a disproportionality analysis for haemodynamic events. Reporting odds ratios (ROR) of carbetocin for hypertension, hypotension, tachycardia, and bradycardia were calculated, with oxytocin-related reports serving as comparators.ResultsOxytocin and carbetocin were mentioned as suspected or interacting drugs in 11,258 and 374 reports, respectively. Resulting RORs for carbetocin were 3.45 (95%CI: 1.72–6.92) for hypertension, 2.65 (1.64–4.28) for hypotension, 2.84 (1.79–4.49) for tachycardia, and 2.00 (0.87–4.60) for bradycardia, when compared to oxytocin. Of 231 patients for whom oxytocin-related tachycardia was reported, 2.6% died, and of 91 patients for whom bradycardia was reported, 2.2% died. No deaths were reported with carbetocin for any of the haemodynamic adverse events.ConclusionCompared to oxytocin, carbetocin showed an elevated reporting for adverse hypertension, hypotension, and tachycardia in pharmacovigilance data. Clinicians should be aware of their patients' individual susceptibility and the possibility of haemodynamic deterioration until causal inferences are possible.