The latest medical research on Transplant Pulmonology

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The del Nido cardioplegia solution is a widely used method for myocardial protection in various settings. However, there is limited evidence of its effectiveness in adult cardiac surgery, and the baseline solution, Plasma Lyte A, is not readily available, leading to the use of alternative baseline solutions. This study aims to investigate the effectiveness of routine del Nido cardioplegia in adult cardiac surgery and the impact of different baseline solutions on myocardial protection and other perioperative outcomes.

This study was a prospective, double-blind randomized parallel group clinical trial conducted at a single tertiary care hospital in Iran. A total of 187 adult patients were evaluated for eligibility, of which 120 met the inclusion criteria for elective isolated CABG surgery. The patients were randomly assigned to three groups, with each group consisting of 40 patients. The control group received a normal saline-based routine del Nido cardioplegia, Intervention Group A received Ringer lactate-based del Nido cardioplegia, and Intervention Group B received plain Ringer-based del Nido cardioplegia. The levels of Creatine Kinase-MB (CK-MB), Troponin T, Troponin I, and lactate were primarily assessed at four different times: after anesthesia induction (Baseline), 2 h, 12 h, and 24 h.

Preoperative demographic and clinical characteristics were the same among groups with insignificant differences (p > 0.05). There was no significant difference among groups based on CK-MB, Troponin T, Troponin I, and lactate levels (p = 0.078, 0.143, 0.311, and 0.129 respectively). However, there was a significant difference in the time effect of Troponin T and Lactate (p = 0.034, p = <0.001).

Normal saline, Ringer lactate, and plain Ringer provide comparable myocardial protection in adult-isolated CABG surgery with modified del Nido cardioplegia. Larger studies are needed to identify the best alternative to Plasma Lyte A while maintaining del Nido cardioplegia as the control.

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The study objective was to characterize compliance with Standardized Therapy after ECMO Program (STEP), an intentional discharge pathway for extracorporeal membrane oxygenation (ECMO) survivors in a US pediatric hospital.

The program identified pediatric ECMO survivors before discharge, appropriate consultations were reviewed and requested, families were educated on ECMO sequelae, and ECMO summaries were sent to pediatricians. Compliance with institutional post-ECMO guidelines was evaluated before and after STEP implementation.

We identified 77 ECMO survivors to hospital discharge (36 [46.8%] before and 41 [53.2%] after STEP implementation). There was a significant increase in complete (38.8% vs. 74.2%, p < 0.001) and time-appropriate neurodevelopmental testing (71.4% vs. 95.6%, p = 0.03). Significant increase in inpatient evaluations by neurology (52.7% vs. 75.6%, p = 0.03) and audiology (66.7% vs. 87.8%, p = 0.02), and in referrals for outpatient audiology (66.6 vs. 95.1%, p = 0.002), physical therapy (P.T.) (63.8% vs. 95.1%, p = 0.001), occupational therapy (O.T.) (63.8% vs. 95.1%, p = 0.001) and speech-language pathology (S.L.P.) (55.5% vs. 95.1%, p < 0.001) were noted.

Implementing an intentional discharge pathway for pediatric ECMO survivors (STEP) successfully increases inpatient and outpatient compliance with hospital and Extracorporeal life support organization (ELSO) follow-up guidelines. It leads to timely and complete neurodevelopmental evaluation.

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Patients supported with extracorporeal life support (ECLS) circuits such as ECMO and CRRT often require high doses of sedatives and analgesics, including ketamine and dexmedetomidine. Concentrations of many medications are affected by ECLS circuits through adsorption to the circuit components, dialysis, as well as the large volume of blood used to prime the circuits. However, the impact of ECLS circuits on ketamine and dexmedetomidine pharmacokinetics has not been well described. This study determined ketamine and dexmedetomidine extraction by extracorporeal circuits in an ex-vivo system.

Medication was administered at therapeutic concentration to blood-primed, closed-loop ex-vivo ECMO and CRRT circuits. Drug concentrations were measured in plasma, hemofiltrate, and control samples at multiple time points throughout the experiments. At each sample time point, the percentage of drug recovery was calculated.

Ketamine plasma concentration in the ECMO and CRRT circuits decreased rapidly, with 43.8% recovery (SD = 0.6%) from ECMO circuits after 8 h and 3.3% (SD = 1.8%) recovery from CRRT circuits after 6 h. Dexmedetomidine was also cleared from CRRT circuits, with 20.3% recovery (SD = 1.8%) after 6 h. Concentrations of both medications were very stable in the control experiments, with approximately 100% drug recovery of both ketamine and dexmedetomidine after 6 h.

Ketamine and dexmedetomidine concentrations are significantly affected by ECLS circuits, indicating that dosing adjustments are needed for patients supported with ECMO and CRRT.

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This retrospective observational study aimed to examine whether clinical inflammatory parameters were associated with the requirement dosage of unfractionated heparin (UFH) to maintain the range of ACT in veno-arterial extracorporeal membrane oxygenation (V-A ECMO) during lung transplantation surgery.

Among all patients who underwent lung transplantation using V-A ECMO from January 2021 to May 2022, 27 patients were included. These patients were divided into two groups based on whether the infusion rate of UFH was increased from the initial infusion rate (7-8 units/kg/h) (increased group, n = 10) or the infusion rate was maintained or decreased (non-increased group, n = 17). The infusion rate was adjusted with an activated clotting time (ACT) target of 160-200 s.

At 1-2 h after starting ECMO, ACT was significantly lower (179.0 (166.5-188.5) versus 224.0 (193.0-242.0) sec, p = 0.006) and white blood cell (WBC) counts were higher in the increased group (12.6 ± 3.3 versus 9.5 ± 4.0 × 103/μL, p = 0.046). The UFH infusion rates were higher in the increased group during the surgery. The cutoff value of WBC count at 1-2 h after starting ECMO for discriminating the need for increasing the UFH dosage was determined as 10.2 × 103/μL (sensitivity 90.0%, specificity 58.8%, area under the curve 0.712) and discrimination of this cut-off value was confirmed as statistically significant (p = 0.018).

These data suggested that WBC count was associated with the requirement of an increase in the UFH infusion rate of V-A ECMO during lung transplantation surgery. Further evaluation is necessary to clarify the role of WBC count in determining the optimal UFH dosage.

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In the state of Kentucky, many status asthmaticus (SA) patients require care in the Pediatric Intensive Care Unit (PICU) and a fraction of these patients may receive "rescue therapies" with inhaled volatile anesthetics (IVA) and/or Extracorporeal Membrane Oxygenation (ECMO). We present a series of such patients with the objective of comparing the clinical parameters of individual patients who received inhaled volatile anesthesia and subsequently the need for ECMO.

Children between 2 and 18 years of age admitted to our PICU from January 2014 to July 2020 with SA were reviewed and categorized as 1) patients who received IVA alone, 2) patients who received IVA and then subsequently ECMO, and 3) patients on ECMO alone.

A total of 1772 children with SA episodes were identified with a mortality of 13 patients. Seven children with SA were identified who received either IVA, ECMO, or both. One patient received only IVA, 5 received both IVA and ECMO and one received only ECMO. All received standard asthma therapies of steroids, albuterol, magnesium sulphate, and aminophylline prior to escalation. Six out of seven refractory SA received IVA, and five (83%) of those were subsequently escalated to ECMO. There was an improvement in mean pH after cannulation compared to IVA. pCO2 levels had no improvement after IVA administration but decreased by an average of 20 points after ECMO. Patients peak inspiratory pressures decreased within the 1st 24 h of ECMO cannulation from a mean of 30 to 18. There were no other complications related to ECMO placement.

While we cannot decisively draw any conclusions from our study due to the small sample, it was noted that there was no clear advantage of using IVA prior to ECMO in our patients. Most patients who received IVA were escalated to ECMO indicating that early ECMO cannulation may be beneficial. Given the high cost and potential complications of both, there is a need for the development of well-defined guidelines for severe SA management in the PICU.

Severe pulmonary vasoconstriction induced by protamine is a rare complication. We report a case of a 77-year-old male patient with a history of mit...

The safe use of cardiopulmonary bypass (CPB) relies upon the ability to administer, monitor, and reverse anticoagulation. Although rare, the factor...

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Ventricular assist devices represent a treatment option for patients with advanced heart failure, offering control over various haemodynamic variables. Similarly, the prescription of exercise within a cardiac rehabilitation programme for heart failure patients is recommended to reduce symptoms, and hospitalisations, improve cardiorespiratory fitness, and increase exercise tolerance. Therefore, exercise prescription can impact those with ventricular assist devices. Given the limited evidence on exercise-based cardiac rehabilitation programmes for this population, this review aims to describe the most commonly used strategies and their health benefits when physical exercise is included in a cardiac rehabilitation programme for patients with ventricular assist devices.

An exploratory review was conducted through searches in the databases: PubMed, SCOPUS, PeDro, and ScienceDirect. The search was limited to studies published between 2013 and 2023. Filters were applied independently by title, abstract, and full text. The included articles were analysed based on the description of the types of cardiac rehabilitation strategies used in patients with ventricular assist devices.

Seven articles were included. Each programme employed a cardiopulmonary exercise test before prescribing physical exercise. The most commonly used strategy was aerobic exercise, predominantly high-intensity interval training (HIIT) with intensities close to 90% of peak VO2, followed by continuous moderate-intensity exercise. Limb strength exercises were included in three programmes.

The analysed literature suggests that cardiac rehabilitation in patients with ventricular assist devices is safe and can provide benefits in cardiorespiratory fitness and exercise tolerance. High-intensity interval training is identified as an appropriate strategy for achieving results, offering short-term improvements.

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Heparin, a commonly used anticoagulant in cardiac surgery, binds to antithrombin III (ATIII) to prevent clot formation. However, heparin resistance (HR) can complicate surgical procedures, leading to increased thromboembolic risks and bleeding complications. Proper diagnosis and management of HR are essential for optimizing surgical outcomes.

Diagnosis of HR involves assessing activated clotting time (ACT) and HR assays. Management strategies were identified through a comprehensive review of the literature, including studies exploring heparin dosage adjustments, antithrombin supplementation, and alternative anticoagulants in cardiac surgery patients with HR. A thorough search of relevant studies on HR was conducted using multiple scholarly databases and relevant keywords, resulting in 59 studies that met the inclusion criteria.

Optimizing the management of HR is crucial for improving surgical outcomes and reducing complications in cardiac surgery patients. Multidisciplinary approaches and emerging anticoagulation strategies hold promise for addressing this challenge effectively.

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Cardiopulmonary bypass is an essential component of cardiothoracic surgeries. However, significant complications such as systemic inflammatory response syndrome (SIRS) resulting from cardiopulmonary bypass (CPB) are a common occurrence due to contact between circulating blood and foreign surfaces that leads to platelet activation. It is suggested that different available CPB circuit coatings can potentially reduce platelet activation. However, there have been no published evidence-based reports confirming these claims. In addition, there is no well-established protocol for studying platelet activation biomarkers during CPB in vitro in a laboratory setting.

CPB was simulated in the laboratory using bovine blood in two different types of coated CPB circuits: Trillium® Biosurface by Medtronic, and XcoatingTM Surface by Terumo. Fresh bovine blood samples were collected and circulated through the CPB circuit following the standard protocol used in the operation rooms. Blood samples were then collected at 5 min, 30 min, and 55 min during the circulation. Blood plasmas were separated and subjected to enzyme-linked immunosorbent assay to measure most established platelet activation markers P-selectin, Platelet Factor 4 (PF4), Glycoprotein IIb/IIIa (GPIIb/IIIa), and β-thromboglobulin (β-TG) at different time points.

The biomarker values at 30 min and 55 min were compared to the base values at 5 min for each type of CPB circuit. The results of the means from all measured biomarkers showed data measurements that indicated no significant variability within each coating. All collected data points fell within ±2 SD of the means, which was considered acceptable variations across technical replicates.  Conclusion: In this study, we were able to establish an in vitro protocol in the laboratory setting that is precise and reliable with minimum intra-variability. This established protocol will allow for future studies in which different coated CPB circuits can be compared for their effectiveness in blocking platelet activation during the CPB.

The usage of cardiopulmonary bypass (CPB) in cardiothoracic surgery contributes to the activation of the inflammatory response. In certain cases, t...

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The Perfusion Measures and Outcomes (PERForm) registry was established in 2010 to advance cardiopulmonary bypass (CPB) practices and outcomes. The registry is maintained through the Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative and is the official registry of the American Society of Extracorporeal Technology.

This first annual PERForm registry report summarizes patient characteristics as well as CPB-related practice patterns in adult (≥18 years of age) patients between 2019 and 2022 from 42 participating hospitals. Data from PERForm are probabilistically matched to institutional surgical registry data. Trends in myocardial protection, glucose, anticoagulation, temperature, anemia (hematocrit), and fluid management are summarized. Additionally, trends in equipment (hardware/disposables) utilization and employed patient safety practices are reported.

A total of 40,777 adult patients undergoing CPB were matched to institutional surgical registry data from 42 hospitals. Among these patients, 54.9% underwent a CABG procedure, 71.6% were male, and the median (IQR) age was 66.0 [58.0, 73.0] years. Overall, 33.1% of the CPB procedures utilized a roller pump for the arterial pump device, and a perfusion checklist was employed 99.6% of the time. The use of conventional ultrafiltration decreased over the study period (2019 vs. 2022; 27.1% vs. 24.9%) while the median (IQR) last hematocrit on CPB has remained stable [27.0 (24.0, 30.0) vs. 27.0 (24.0, 30.0)]. Pump sucker termination before protamine administration increased over the study period: (54.8% vs. 75.9%).

Few robust clinical registries exist to collect data regarding the practice of CPB. Although data submitted to the PERForm registry demonstrate overall compliance with published perfusion evidence-based guidelines, noted opportunities to advance patient safety and outcomes remain.

The latest medical research on Transplant Pulmonology

Comparison of routine del Nido cardioplegia vs two types of modified del Nido cardioplegias for myocardial protection among patients undergoing coronary artery bypass grafting (CABG) surgeries: A randomized double-blind clinical trial.

Standardized therapies after ECMO program (STEP); a novel approach to pediatric post-ECMO care.

Extraction of ketamine and dexmedetomidine by extracorporeal life support circuits★.

Increased white blood cell count is associated with an increased demand for unfractionated heparin during veno-arterial extracorporeal oxygenation in lung transplantation.

Outcomes in patients who received ECMO and/or volatile anesthetics as rescue therapies for status asthmaticus★.

A case of the effective inhalation of nitric oxide therapy for caused severe pulmonary hypertension with protamine neutralization of systemic heparinization during totally endoscopic minimally invasive cardiac surgery.

Cardiopulmonary bypass in a pediatric patient with factor XII deficiency.

Effects of cardiac rehabilitation in patients with ventricular assist devices: a scoping review.

Heparin resistance management during cardiac surgery: a literature review and future directions.

Designing an experimental method for assessing biocompatibility of circuit coatings using biomarkers for platelet activation during cardiopulmonary bypass.

Impact of extracorporeal haemoadsorption during prolonged cardiopulmonary bypass on the incidence of acute kidney injury.

Perfusion Measures and Outcomes (PERForm) registry: First annual report.

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