bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring the Conjunctiva for Carbon Dioxide and Oxygen Tensions and pH During Cardiopulmonary Bypass
Authors: Weiss Irwin K. , Isenberg Sherwin J. , McArthur David L. , Del Signore Madeline , McDonald John S.
Published: July 2023

The purpose of this study was to measure, for the first time, multiple physiologic parameters of perfusion (pH, PCO2, PO2, and temperature) from the conjunctiva of adult patients during cardiopulmonary bypass while undergoing cardiothoracic surgery. Ten patients who underwent either intracardiac valve repair, atrial septal defect repair, or coronary artery bypass graft surgery had placement of a sensor which directly measured pH, PCO2, PO2, and temperature from the conjunctiva. Data were stratified into seven phases (0–5 minutes prior to bypass; 0–5, 6–10, and 11–15 minutes after initiation of bypass; 0–5 minutes prior to conclusion of bypass; and 0–5 and 6–10 minutes after bypass) and analyzed using a mixed model analysis. The change in conjunctival pH over the course of measurement was not statistically significant (p = .56). The PCO2 level followed a quadratic pattern, decreasing from a mean pre-bypass level of 37.7 mmHg at baseline prior to the initiation of cardiopulmonary bypass to a nadir of 33.2 mmHg, then increasing to a high of 39.4 mmHg at 6–10 minutes post bypass (p < .01). The PO2 declined from a mean pre-bypass level of 79.5 mmHg to 31.3 mmHg by 6–10 minutes post bypass and even post-bypass, it never returned to baseline values (p < .01). Temperature followed a pattern similar to PCO2 by returning to baseline levels as the patient was re-warmed following bypass (p < .01). There was no evidence of any eye injury or inflammation following the removal of the sensor. In the subjects studied, the conjunctival sensor yielded reproducible measurements during the various phases of cardiopulmonary bypass without ocular injury. Further study is necessary to determine the role of conjunctival measurements in critical settings.
Clinical Evaluation of the Accuracy and Precision of the CDI 500 In-line Blood Gas Monitor With and Without Gas Calibration
Authors: Bellaiche Anne Louise , Nielsen Peter F. , Brantlov Steven , Møller Marianne B. , Winterdahl Michael
Published: July 2023

During cardiopulmonary bypass blood gases can be analyzed with laboratory equipment or with an in-line monitor giving instant results. The manufacturer of the CDI 500 in-line blood gas monitor recommends gas calibration before use. In acute cases there may not be time to perform a gas calibration. We hypothesized that after calibration against laboratory results, the CDI values of pH, pO2, and pCO2will keep the same level of accuracy, whether the CDI has been gas calibrated or not. We performed a prospective randomized observational study using a study group without gas calibration (29 patients) and a control group with gas calibration (29 patients). Blood sampling was done at the beginning of bypass, and 30 minutes later. After each blood sample the CDI was in-vivo calibrated to the values simultaneously obtained from the ABL. Before in-vivo calibration values from the CDI without gas calibration were significantly different from the ABL-values in accuracy as well as precision, whereas the results from the gas calibrated CDI were largely consistent with the ABL. Before in-vivo calibration, the CDI without gas calibration was completely unreliable. After in-vivo calibration there was no statistical difference between the values of the CDI with and without calibration. We recommend gas calibration of the CDI before use in the period before in-vivo calibration.
Massive Systemic Air Embolism during Extracorporeal Membrane Oxygenation Support of a Neonate with Acute Respiratory Distress Syndrome after Cardiac Surgery
Authors: Timpa Joseph G. , O’Meara Carlisle , McILwain R. Britt , Dabal Robert J. , Alten Jeffrey A.
Published: July 2023

Extracorporeal membrane oxygenation (ECMO) is universally accepted as a potential lifesaving therapy for neonates suffering severe cardiorespiratory failure, with survival reported as 81% weaning off ECMO and 69% to hospital discharge in this population. Although ECMO may reduce mortality in certain neonatal patients, it is associated with significant complications. Air in the circuit complicates 4.9% of neonatal ECMO runs, and it is crucial that all ECMO caregivers are trained in the prevention of air embolism and possess the knowledge necessary to efficiently identify and remove air from the ECMO circuit to prevent life threatening consequences. We present a fatal case of neonatal systemic air embolism leading to massive entrainment of air into the ECMO venous return cannula of a neonatal patient with acute respiratory distress syndrome following repair of obstructed total anomalous pulmonary venous connection. We describe the pathophysiology and presentation of this rare condition and the importance of early recognition, due to its high mortality rate.
A Technique for Autologous Priming of the Veno-Venous Bypass Circuit during Liver Transplantation
Authors: Shackelford Anthony G. , Hodge Ashley B. , Chavin Kenneth D. , Baliga Prabhakar K.
Published: July 2023

Orthotopic liver transplantations (OLT) have been associated with significant blood loss and hemodilution, necessitating significant homologous blood component replacement. Increasing administration of homologous blood products has been found to be inversely related to patient and graft survival. Various methods to reduce the amount of blood products patients receive during OLT, such as antifibrinolytic therapy, thromboelastography-guided transfusion, phlebotomy, reduced central venous pressures intraoperatively, and the use of the veno-venous bypass (VVB) circuit, have been explored. The asanguineous priming volume of the VVB circuit increases the likelihood of the patient receiving homologous blood products due to hemodilution. It was reasoned that autologous priming of the VVB circuit in OLT surgery was a plausible adjunctive blood conservation technique given its application to the extracorporeal circuit during cardiac surgery. We describe our technique of modifying the VVB circuit for autologous priming. This technique adds minimal risk and a small amount of cost to the procedure, requires slightly more communication among members of the surgical team, and with proper sequencing, adds no additional length to the surgical procedure. It is recommended that this technique be considered for addition to the arsenal of blood conservation techniques when VVB is used during OLT.
Pig Heart Preservation with Antegrade Intracellular Crystalloid versus Antegrade/Retrograde Miniplegia
Authors: Portilla-de Buen Eliseo , Leal Caridad , García-Martínez David , Cornejo Agustín , Zepeda Alonso , Aburto Enrique
Published: July 2023

Both histidine-tryptophan-ketoglutarate (HTK) solution and Braile miniplegia are commercially available and used with high success. The objective of this work was to compare the effects of both strategies in an animal model. Twelve pigs were divided into control, HTK, or Braile groups using a model of controlled global cardiac ischemia/reperfusion under cardiopulmonary bypass with 1 hour heart ischemia followed by 2 hour reperfusion. No significant differences were found over time or between groups for heart rate, arrhythmia, number of defibrillations required, blood gases, myocardial lactate production, myocardial oxygen consumption, nor coronary flow index. The Braile strategy was associated with a lower 120 minute postreperfusion coronary vascular resistance with higher water content, leukocyte infiltration, and oxidative damage compared with controls. Drainage of HTK solution to the venous return was followed by higher potassium and lower sodium blood concentrations. One-hour heart preservation with HTK or Braile systems followed by 2 hour reperfusion both allow for acceptable preservation of the healthy pig myocardium. Maneuvers such as leukocyte filtration or hemofiltration may further improve these conditions.
Randomized Trial of the Terumo Capiox® FX05 Oxygenator with Integral Arterial Filter versus Terumo Capiox® Baby RX05 and Terumo Capiox® AF02 Arterial Filter in Infants Undergoing Cardiopulmonary Bypass
Authors: Nuszkowski Mark M. , Deutsch Nina , Jonas Richard A. , Zurakowski David , Montague Erin , Holt David W.
Published: July 2023

The purpose of this clinical trial was to evaluate the effect of the Terumo Capiox® FX05 oxygenator with integrated arterial filter during cardiopulmonary bypass (CPB) compared with the Terumo Capiox® RX05 Baby RX and arterial filter on inflammatory mediators and blood product utilization. Forty patients weighing less than 10 kg who underwent congenital heart surgery utilizing cardiopulmonary bypass were randomized into either oxygenator group. The endpoints included measuring inflammatory markers at six different time points (preoperative baseline, CPB circuit being primed, 15 minutes after CPB initiation, status post protamine administration, prior to transport to intensive care unit, and within 12 to 24 hours post surgery), blood product utilization, extubation time, and days until discharge. The inflammatory mediators showed no significant differences between oxygenators at any time points. However, looking at the inflammatory mediators of both the FX and RX groups combined, a statistically significant difference was seen in interleukin (IL)-6 at 12/24 hour post surgery (p< .001) versus baseline and all other time points. IL-8 at status post protamine (p< .001) and 12/24 hours post surgery (p< .001) demonstrated significant differences versus all other time points, and IL-10 at status post protamine (p< .001) and prior to leaving the operating room (p< .001) were statistically different compared to all other time points. Cardiopulmonary bypass stimulates the systemic inflammatory response through various components of the extracorporeal system. This investigation did not find significant differences in cytokines interferon-γ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12 p70, tumor necrosis factor (TNF)-α, and TNF-β when comparing these two oxygenators. It is well known that various mechanisms contribute to the levels of cytokines circulating in a patient’s blood volume and many manipulations throughout cardiac surgery have the ability to demonstrate anti-inflammatory interventions. Further investigation is needed as to how modification of the extracorporeal circuit may minimize increases in inflammatory mediators.
Simultaneous Individually Controlled Upper and Lower Body Perfusion for Valve-Sparing Root and Total Aortic Arch Replacement: A Case Study
Authors: Fernandes Philip , Mayer Rick , Adams Corey , Chu Michael W.A.
Published: July 2023

Optimal perfusion strategies for extensive aortic resection in patients with mega-aortic syndromes include: tailored myocardial preservation, antegrade cerebral perfusion, controlled hypothermia and selective organ perfusion. Typically, the aortic arch resection and elephant trunk procedure are performed under hypothermic circulatory arrest with myocardial and cerebral protection. However, mesenteric and systemic ischemia occur during circulatory arrest and commonly rely upon deep hypothermia alone for metabolic protection. We hypothesized that simultaneously controlled mesenteric and systemic perfusion can attenuate some of the metabolic debt accrued during circulatory arrest, which may help improve perioperative outcomes. The perfusion strategy consisted of delivering a 1 to 3 liter per minute flow at 25°C to the head/upper body via right axillary graft and simultaneous perfusion to the lower body/mesenteric organs of 1 to 3 liters per minute at 30°C via a right femoral arterial graft. We describe our technique of simultaneous mesenteric, systemic, cerebral and myocardial perfusion, and protection utilized for a young male patient with Marfan’s syndrome, while undergoing a valve sparing root replacement, total arch replacement and elephant trunk reconstruction. This perfusion technique allowed us to deliver differential flow rates and temperatures to the upper and lower body (cold head/warm lower body perfusion) to minimize ischemic debt and quickly reverse metabolic derangements.
Hypothermic Cardiac Arrest in the Homeless: What Can We Do?
Authors: Sansone Fabrizio , Flocco Roberto , Zingarelli Edoardo , Dato Guglielmo Mario Actis , Punta Giuseppe , Parisi Francesco , Forsennati Pier Giuseppe , Bardi Gian Luca , Imbastaro Iulia , Chiolero Claudia , Balossino Adalberto , Borin Paolo , Peretto Viviana , del Ponte Stefano , Casabona Riccardo
Published: July 2023

Accidental deep hypothermia with body temperature <28°C induces high mortality rates for neurological and cardiac complications. Although several reports described successful treatment of hypothermic arrest by extracorporeal membrane oxygenation (ECMO), the field of warming in the homeless is almost completely unquestioned although the malnutrition and the co-morbidities are usually believed as relevant risk factors for poor outcome. This article describes the experience of successful warming by ECMO in two homeless victims of unwitnessed cardiac arrest, who survived without neurological or cardiac complications. In conclusion, this is an initial experience and further research is required, although our results are appreciable in this high risk subset of population.
Oxygenator Safety Evaluation: A Focus on Connection Grip Strength and Arterial Temperature Measurement Accuracy
Authors: Newland Richard F. , Baker Robert A. , Sanderson Andrew J. , Tuble Sigrid C. , Tully Phil J.
Published: July 2023

This report describes the assessment of three specific safety-related specifications in the consideration of an alternate oxygenator; first the grip strength relationship between various oxygenator connectors and SMARxT® tubing, second, the grip strength of various biopassive tubings and an isolated SMARxT® connector, and finally, the accuracy of the arterial outlet temperature measurement. Grip strength experiments for the connections between the SMARxT® tubing and the venous reservoir outlet and the oxygenator venous inlet and oxygenator arterial outlet of the Medtronic Affinity®, Sorin Synthesis®, Sorin Primox®, and Terumo Capiox® RX25 oxygenators were performed. In addition we compared the grip strength of polyvinyl chloride, Physio®, Trillium®, Carmeda®, X-Coating®, and SMARxT® tubing. The accuracy of the integrated arterial outlet temperature probes was determined by comparing the temperatures measured by the integrated probe with a precision reference thermometer. Connector grip strength comparisons for the evaluation oxygenators with SMARxT® tubing showed significant variation between oxygenators and connections (p= .02). Evaluation of the arterial outlet showed significant variation between evaluation oxygenators, while at the venous reservoir outlet and oxygenator inlet, there were no significant differences. Grip strength comparison data for the various tubing types demonstrated a main effect for tubing type F(5, 18) = 8.01,p= .002, ηp2= .77. Temperature accuracy measurements demonstrated that all oxygenators overread the arterial outlet temperature at 15°C, whilst at temperatures ≥25°C, all oxygenators underread the arterial outlet temperature. The integrity of SMARxT® tubing connection is influenced by the connector type, and may decline over time, highlighting the importance to not consider interchanging components of the bypass circuit as inconsequential.
Modification of Sodium, Glucose, Potassium, and Osmolarity in Packed Red Blood Cells and Fresh Frozen Plasma Using a Desktop Hemoconcentrator Setup
Authors: Striker Carrie Whittaker , Woldorf Stacia , Holt David
Published: July 2023

Massive transfusion with packed blood cells (PRBCs) or fresh frozen plasma (FFP) can result in dangerous complications including stroke, kidney failure, and cardiac arrest. A simple, bench top technique using a hemoconcentrator and dialysate solution is described to correct critical values of sodium, glucose, potassium, and osmolarity in PRBCs and FFP. Sodium, glucose, and osmolarity were corrected to normal or near normal values. Elevated potassium was reduced by 65%, but not completely normalized. A simple, bench top method for correcting dangerous abnormalities with PRBCs and FFP can be used to improve the safety of massive blood transfusion.
Extracorporeal Membrane Oxygenation as a Platform for Recovery: A Case Report of a Child with Pulmonary Hemorrhage, Refractory Hypoxemic Respiratory Failure, and New Onset Goodpasture Syndrome
Authors: Dalabih Abdallah , Pietsch John , Jabs Kathy , Hardison Daphne , Bridges Brian C.
Published: July 2023

We report a case of a 9-year-old female with acute pulmonary hemorrhage and refractory hypoxemic respiratory failure secondary to Goodpasture syndrome (GS). After failing treatment with high frequency oscillatory ventilation and inhaled nitric oxide, she was successfully managed with venovenous extracorporeal membrane oxygenation (VV ECMO). The patient’s weight at the time of cannulation was 31 kg. A 19 French 18 cm (arterial) Biomedicus cannula was inserted in the right internal jugular vein and used as the drain. A 17 French 50 cm (venous) Biomedicus cannula was inserted in the right femoral vein and used as the return. Then the patient was anticoagulated with 100 units/kg of intravenous heparin and the circuit was primed with one unit of packed red blood cells. VV ECMO was performed with an SIII Sorin roller head pump with integrated servo regulator and a Quadrox D Bioline coated oxygenator. Despite systemic anticoagulation with heparin, the patient’s pulmonary hemorrhage resolved. Extracorporeal membrane oxygenation served as a platform through which we were able to provide renal replacement therapy and plasmapheresis. The patient was successfully discharged home with normal pulmonary function.
Improvements in Survival and Neurodevelopmental Outcomes in Surgical Treatment of Hypoplastic Left Heart Syndrome: A Meta-Analytic Review
Authors: Sistino Joseph J. , Bonilha Heather Shaw
Published: July 2023

The purpose of this study was to analyze the changes over the past two decades in hospital survival and neurodevelopmental outcomes after surgical treatment for hypoplastic left heart syndrome. The hypothesis for this study is that increasing hospital survival following the Stage I Norwood (S1N) procedure is associated with improvements in neurodevelopmental outcomes. Studies included in the meta-analysis were identified by searching Ovid MEDLINE® from January 1980 to October 2010. A total of 72 articles were identified. Fifteen single-center study articles were appropriate for obtaining survival data and 14 were used for neurodevelopmental outcomes. Wechsler Intelligence Test IQ scores and the Bayley II Mental Development (MDI) and Psychomotor Development Indices (PDI) were the primary neurodevelopmental outcomes included in this meta-analysis. Metaregression analysis using a mixed-effects model compared the percent survival and neurodevelopmental scores with the year of surgery. Hospital survival for the S1N operation increased significantly from 1996 to 2007 (p< .05). The overall mean survival during this time period was 80.05% (95% confidence interval [CI], 76.4–84.0%). Standardized Wechsler IQ scores increased significantly from 1989 to 1999 (p< .05) and the mean IQ was 85.09 (95% CI, 82.3–89.5). The Bayley II MDI increased significantly from 1998 to 2005 (p< .05) with a mean MDI of 86.9 (95% CI, 84.9–88.9). The Bayley II PDI increased significantly from 1998 to 2005 (p< .05) with a mean PDI of 73.4 (95% CI, 71.2–75.5). Increased survival has been associated with improved but below normal neurodevelopmental outcomes.
Hyperoxia: A Review of the Risks and Benefits in Adult Cardiac Surgery
Authors: Young Robert W.
Published: July 2023

Perioperative hyperoxia has been claimed to have a number of therapeutic advantages. However, in the setting of cardiac surgery and cardiopulmonary bypass (CPB), enthusiasm for its use has been tempered by concerns regarding the effect of high partial pressures of oxygen on cardiac, vascular, and respiratory function and the potential for exacerbation of ischemia–reperfusion injury. There is encouraging evidence from animal studies that hyperoxia is effective in myocardial preconditioning, at least in nondiseased hearts. There is also evidence that hyperoxia reduces gas microemboli production and longevity during CPB, although it is unclear whether this translates into a clinical benefit in terms of a reduction in postoperative neurological morbidity. Hyperoxia leads to changes in cardiovascular function. However, the effects of these changes remain unclear. At a tissue level, there is evidence that hyperoxia does not lead to improvement in partial pressure of oxygen. Indeed, the opposite may be the case with reductions in capillary density leading to areas of reduced tissue oxygenation. The risks of hyperoxia in association with CPB include lung injury, increased systemic reactive oxygen species generation, and exacerbation of reactive oxygen species-mediated myocardial injury at the time of reperfusion. Again, it is difficult to know whether the changes demonstrated are temporary or if they translate into a worsening of clinical outcomes. In conclusion, perhaps the key to the use of hyperoxia is in the timing. In the period pre-CPB, hyperoxia may precondition the myocardium and, paradoxically, confer a degree of protection against reactive oxygen species-induced injury at the time of reperfusion. Hyperoxia during CPB is probably harmful and should be avoided unless the risk from gas microemboli is thought to be significant, in which case the risks and benefits to the individual patient must be weighed.
Quality-of-Life Measures for Cardiac Surgery Practice and Research: A Review and Primer
Authors: Tully Phillip J.
Published: July 2023

Declining mortality and major morbidity rates after cardiac surgery have led to increasing focus on patient quality of life (QOL). Beyond longevity, the impact of cardiac surgery on day-to-day functioning is incredibly salient to patients, their spouses, and families. As such, QOL measures are a welcome and sometimes necessary addition to clinical trials. However, how does one navigate the expansive market of QOL questionnaires, which QOL measures are applicable to cardiac surgery units, and how can they be used meaningfully in clinical practice? Because nearly two decades have passed since QOL measures were reviewed for relevance to cardiac surgery settings, an overview is provided of various generic (Short Form Health Survey [SF-36], Sickness Impact Profile, Nottingham Health Profile) and disease-specific QOL measures (Duke Activity Status Index, Seattle Angina Questionnaire, MN Living with Heart Failure Questionnaire; Heart-QOL) with examples from cardiac surgery studies. Recommendations are provided for the application of QOL measures to clinical trials and the impact on clinical decision-making is discussed. The paucity of methodologically sound QOL studies highlights the necessity for further rigorous empirical data to better inform treatment efficacy studies and clinical decision-making.
A Single-Center Experience with Luminal Venous Cannulae Obstruction Caused by Clot Formation during Bypass
Authors: Matte Gregory S. , Howe Robert J. , Pigula Frank
Published: July 2023

Our institution experienced two bypass cases from January through December 2011 in which venous return was significantly variable and at times poor. Luminal clot formation in the venous cannulae was found in each case postbypass. These events were captured and monitored through our institution’s Non-Routine Event Reporting Program and eventually reported to the Food and Drug Administration (FDA). We began inspecting all venous cannulae postbypass in December 2011. During a subsequent 9-month surveillance period, we documented 33 venous cannulae in 21 patients with luminal clot formation. Only one cannula during this surveillance period required change-out on bypass. The manufacturer eventually identified changes in production that likely caused the clotting events. The manufacturer modified their production methods and began supplying cannulae produced under the new method in September 2012. We have experienced only one clotting event with the new cannulae and in that instance, the metal tip was found to be defective. We recommend inspection of all venous cannulae postbypass with internal, manufacturer, and FDA reporting for those noted to have luminal clot formation.
Brachial Arterial Temperature as an Indicator of Core Temperature: Proof of Concept and Potential Applications
Authors: Pawley Matthew D.M. , Martinsen Paul , Mitchell Simon J. , Cheeseman James F. , Merry Alan F. , Willcox Timothy , Grieve Robert , Nand Parma , Davies Elaine , Warman Guy R.
Published: July 2023

There is potential for heat loss and hypothermia during anesthesia and also for hyperthermia if heat conservation and active warming measures are not accurately titrated. Accurate temperature monitoring is particularly important in procedures in which the patient is actively cooled and then rewarmed such as during cardiopulmonary bypass surgery (CPB). We simultaneously measured core, nasopharyngeal, and brachial artery temperatures to investigate the last named as a potential peripheral temperature monitoring site. Ten patients undergoing hypothermic CPB were instrumented for simultaneous monitoring of temperatures in the pulmonary artery (PA), aortic arterial inflow (AI), nasopharynx (NP), and brachial artery (BA). Core temperature was defined as PA temperature before and after CPB and the AI temperature during CPB. Mean deviations of BA and NP temperatures from core temperature were calculated for three steady-state periods (before, during, and after CPB). Mean deviation of BA and NP temperatures from AI temperature was also calculated during active rewarming. A total of 1862 measurements were obtained and logged from eight patients. Mean BA and NP deviations from core temperature across the steady-state periods (before, during, and after CBP) were, respectively: .23 ± .25, −.26 ± .3, and −.09 ± .05°C (BA), and .11 ± .19, −.1 ± .47, and −.04 ± .3°C (NP). During steadystate periods, there was no evidence of a difference between the mean BA and NP deviation. During active rewarming, the mean difference between the BA and AI temperatures was .14 ± .36°C. During this period, NP temperature lagged behind AI and BA temperatures by up to 41 minutes and was up to 5.3°C lower than BA (mean difference between BA and NP temperatures was 1.22 ± .58°C). The BA temperature is an adequate surrogate for core temperature. It also accurately tracks the changing AI temperature during rewarming and is therefore potentially useful in detecting a hyperthermic perfusate, which might cause cerebral hyperthermia.
The Effects of Pressure on Gases in Solution: Possible Insights to Improve Microbubble Filtration for Extracorporeal Circulation
Authors: Herbst Daniel P.
Published: July 2023

Improvements in micropore arterial line filter designs used for extracorporeal circulation are still needed because microbubbles larger than the rated pore sizes are being detected beyond the filter outlet. Linked to principles governing the function of micropore filters, fluid pressures contained in extracorporeal circuits also influence the behavior of gas bubbles and the extent to which they are carried in a fluid flow. To better understand the relationship between pressure and microbubble behavior, two ex vivo test circuits with and without inline resistance were designed to assess changes in microbubble load with changes in pressure. Ultrasound Doppler probes were used to measure and compare the quality and quantity of microbubbles generated in each test circuit. Analysis of microbubble load was separated into two distinct phases, the time periods during and immediately after bubble generation. Although microbubble number decreased similarly in both test circuits, changes in microbubble volume were significant only in the test circuit with inline resistance. The test circuit with inline resistance also showed a decrease in the rate of volume transferred across each ultrasound Doppler probe and the microbubble number and size range measured in the postbubble generation period. The present research proposes that fluid pressures contained in extracorporeal circuits may be used to affect gases in solution as a possible method to improve microbubble filtration during extracorporeal circulation.
Cryoprecipitate and Platelet Administration during Modified Ultrafiltration in Children Less than 10 kg Undergoing Cardiac Surgery
Authors: Mejak Brian L. , Ing Richard J. , McRobb Craig , Ellis W. Cory , Lawson D. Scott , Twite Mark D. , Jaggers James
Published: July 2023

The timing of blood product administration after cardiopulmonary bypass (CPB) may influence the amount of postoperative transfusion and chest tube output. We performed a retrospective study of a novel technique of administering blood products during modified ultrafiltration (MUF) in congenital cardiac surgery. A Control Group (CG;n= 55) received cryoprecipitate and platelets after modified ultrafiltration. The Treatment Group (TG;n= 59) received cryoprecipitate and platelets during MUF. Volumes of blood products transfused in the operating room, initial coagulation parameters in the cardiac intensive care unit, and first 24-hour chest tube output were recorded. Age (116 ± 198 versus 84 ± 91 days), weight (4.6 ± 1.8 versus 4.5 ± 1.4 kg), duration of bypass (121 ± 50 versus 139 ± 57 minutes), and Aristotle scoring (9.3 ± 2.7 versus 9.1 ± 3.1) were not significantly different when comparing the control and treatment groups, respectively. Intraoperative packed red blood cells (74.4 ± 34.8 versus 79.3 ± 58.0 mL/kg,p= .710), fresh-frozen plasma (58.3 ± 27.1 versus 59.1 ± 27.2 mL/kg,p= .849), cryoprecipitate (7.3 ± 5.1 versus 8.6 ± 5.9 mL/kg,p= .109), and platelet (19.0 ± 14.6 versus 23.7 ± 20.8 mL/kg,p= .176) administration were the same in the control and treatment groups, respectively. However, fibrinogen levels on arrival in the coronary intensive care unit were significantly higher (305 ± 80 versus 255 ± 40 mg/dL,p< .001) in the CG compared with the TG. Twenty-four-hour chest tube output was not significantly different but the CG (17.76 ± 9.34 mL/kg/24 hours) was trending lower than the TG (19.52 ± 10.94 mL/kg/24 hours,p= .357). In an attempt to minimize CPB-associated bleeding and transfusions, we changed our practice by adjusting the timing of blood product administration after patient separation from CPB. The goals of the change in practice were not measurably different in terms of shorter intraoperative times, fewer blood transfusions, or less chest tube output at our institution.
The Thoratec® CentriMag® for Pediatric Right Ventricular Failure
Authors: Hodge Ashley B. , Yeager Catherine J. , Preston Thomas J. , Savage Andrew J. , Butts Ryan J. , Kavarana Minoo N.
Published: July 2023

Acute right ventricular failure post heart transplantation in the pediatric population has not been well documented. Treatment using medical therapies including inotropes and nitric oxide are often inefficient for pediatric patients. Extracorporeal membrane oxygenation has been traditionally used in children until a long-term decision can be made. As a result of the emergence of smaller assist devices, pediatric practitioners now have more options available to treat this patient population. We describe the successful use of the Thoratec® CentriMag® in a pediatric patient posttransplantation with acute right ventricular failure.
A Novel Method for Percutaneous Insertion of a Right Ventricular Assist Device
Authors: Avgerinos Dimitrios V. , DeBois William , Mongero Linda , Krieger Karl , Salemi Arash
Published: July 2023

Right heart failure is a rare but often fatal complication both in the pre- and postoperative setting. Right heart support with a ventricular assist device inserted in the operating room through median sternotomy can be a time-consuming procedure that requires a reoperation for removal. In cases of urgent need of right heart support, a percutaneous technique option may be of benefit. We present our initial experience with a percutaneously inserted right ventricular assist device (RVAD) in an elderly patient with severe right heart failure. An 81-year-old female patient underwent combined aortic and mitral valve replacement at our institution. During the first postoperative evening, the patient sustained sudden cardiovascular collapse and a bedside transesophageal echocardiogram revealed severe right heart failure. A coronary angiogram showed thrombosis of the right coronary artery, which was cleared with a suction device. As a result of the patient’s critical condition, it was decided that an RVAD was needed as a bridge to recovery. The patient’s condition improved significantly almost immediately. Her right heart function recovered over the next few days and the RVAD was removed at the bedside. She made a complete recovery and was discharged home. This patient is a prime example that a totally RVAD can be inserted in urgent situations easily and safely under fluoroscopic and echocardiographic guidance. More clinical experience with percutaneous RVADs is required to establish this technique as an alternative equivalent to the traditional open method. Right heart failure complicates many heart diseases both in the pre- and the postoperative setting. In cases of urgent need of right heart support, a percutaneous technique of a RVAD is needed for a successful outcome. We present our initial experience with a percutaneously inserted RVAD in an elderly patient with severe postoperative right heart failure.
Custodiol® HTK Cardioplegia Use in Robotic Mitral Valve
Authors: Patel Nirav , DeLaney Ed , Turi Gerard , Stapleton Thomas
Published: July 2023

Robotic surgery is a growing subspecialty in cardiac surgery. Custodiol® HTK cardioplegia offers long-term myocardial protection, decreased metabolism, and eliminates multiple cardioplegia dosing. This article reviews the technique, strategy, and considerations for use of Custodiol® HTK for myocardial protection in robotic mitral valve surgery.
Women in Perfusion: A Survey of North American Female Perfusionists
Authors: Brewer Stacey L. , Mongero Linda B.
Published: July 2023

Perfusion as a career has long been dominated by men (American Board of Cardiovascular Perfusion, Booklet of information since 1975). Women represent 33.3% of the present workforce in North America (1187 certified women). In the 1900s, fewer than 20% of women participated in the labor force compared with 75% today and growing (1). In addition women make only 77 cents for every dollar that men earn and the more education a woman has, the greater the disparity in her wages (2). Only 53% of employers provide at least some replacement pay during periods of maternity leave (2). The purpose of this survey was to poll women in perfusion to evaluate concerns and opinions in their careers and to compare this with the female labor force. In October 2011, a 40-question survey (surveymonkey.com) was made available to all female perfusionists in North American by postcard mailing through the American Board of Cardiovascular Perfusion. There were 538 responses to the survey, which is 45% of all female certified perfusionists in North America. A total of 32.6% of the survey participants have been in perfusion for more than 20 years and 75% are staff perfusionists, working for a hospital (59.5%) rather than a contract group (36.7%). A total of 44.7% of women who had children during their employment were out on leave 10 weeks or less. A total of 95.9% feel they miss important family functions as a result of their work schedules and 63% consider themselves under moderate stress. Direct supervision of the participants by men occurred in 76.5% of cases, and 68.2% felt that they were treated with the same respect as male coworkers. Nonetheless, 50.9% felt discriminated against because of gender. This survey suggests that the female perfusionists in North America share the same difficulties as women in the labor force. The role of women in society in general is clearly changing. Female perfusionists will be part of that change. Seventy percent of those surveyed would recommend perfusion as a career to both men and women.
Regional Variation in Arterial Saturation and Oxygen Delivery during Venoarterial Extracorporeal Membrane Oxygenation
Authors: Avgerinos Dimitrios V. , DeBois William , Voevidko Lilia , Salemi Arash
Published: July 2023

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) can be lifesaving in patients with cardiopulmonary collapse. However, observation studies have implied that oxygenated blood does not pass in a retrograde fashion from the VA-ECMO circuit to the aortic root and arch when the femoral artery (FA) is used. This study aims at accurately measuring the oxygen saturation in various arteries during VA-ECMO through different cannula sites. A total of 20 patients with VA-ECMO were in the study. Fourteen patients had FA cannulation, two patients received axillary arterial (AA) cannulation, and four patients received cannulation of the ascending aorta. Oxygen saturation was measured simultaneously in the radial artery and oxygenator outlet. In the patient group with FA cannulation, the oxygen saturation was lower in the radial artery (97%) when compared with the oxygenator outlet (>99%). In the subset group of patients with severe lung dysfunction, oxygen saturation was even lower in the radial artery (73% saturation). In the patient group with AA cannulation, the oxygen saturation and partial oxygen pressure (PO2) in the oxygenator outlet and radial artery were similar (99% or greater). In the patient group with direct ascending aorta cannulation, the oxygen saturation and PO2 in the oxygenator outlet and radial artery were similar as well. Regional variations occur in the blood oxygen saturation depending on the site of the arterial cannulation in patients with VA-ECMO. With FA cannulation, the oxygen saturation in the radial artery is significantly lower than the one in the oxygenator outlet. This may imply that the coronaries and the brain receive hypoxic blood from the left ventricle. These results suggest that antegrade cannulation for VA-ECMO improves oxygen delivery to the proximal aorta distribution.
Heparin Dose and Postoperative Bleeding in Patients Undergoing Cardiopulmonary Bypass
Authors: Rosin Mark W. , Holt David
Published: July 2023

Heparin is the most widely used anticoagulant for cardiopulmonary bypass (CPB). Several authors suggest that lower doses of heparin during CPB would produce lower postoperative chest tube losses and fewer transfusion events. In the present study, a heparin dose–response (HDR) test was used to determine the heparin dose for each patient. We hypothesize that higher doses of heparin do not cause increased postoperative bleeding and transfusion events in postoperative patients undergoing CPB when the heparin dose is determined by a HDR test. This prospective observational study followed 66 patients undergoing CPB-supported primary coronary artery bypass grafting. Patients were placed in one of two groups, sensitive (n = 37) or resistant (n = 29) based on the result of a HDR test slope. Data on patient characteristics, secondary outcomes, transfusion, and the primary outcome, chest tube losses, were collected. Patient characteristics differed in the baseline activated coagulation time (ACT) and thromboelastograph G parameter as well as number of patients with hypercholesterolemia. The resistant group had lower postheparin and postprotamine ACTs and heparin sensitivity index. Initial heparin dose, total heparin dose, heparin dose per kilogram, HDR, and protamine dose were higher in the heparin-resistant group. The primary outcome, postoperative chest tube loss volume, was collected at four time points and the two groups were then compared. The heparin-resistant group was noninferior to the sensitive group and had clinically fewer transfused patients and transfusion events. The resistant group was noninferior to the sensitive group with respect to chest tube losses at all measured time points. Higher doses of heparin determined by a HDR test do not cause increased postoperative chest tube losses or increased transfusion events.
Enlarged and Echogenic Kidneys While on a Pediatric Ventricular Assist Device
Authors: Poudel Atul , Neiberger Richard
Published: July 2023

Pediatric ventricular assist devices (VAD) specially designed for small children have been increasingly implanted in North America. We present unexpected renal findings developing in three children receiving circulatory support using VAD (EXCOR Pediatric Ventricular Assist Device; Berlin Heart Inc., The Woodlands, TX). The mechanisms of heart failure in these children included: 1) hypoplastic ventricle with aortic stenosis; 2) anomalous coronary artery arising from the pulmonary artery; and 3) idiopathic progressive heart failure. During circulatory support with VAD, each child had coagulation times maintained at 1.5–2.5 times normal. Each child had normal or mildly reduced renal function. Each of these children had imaging studies (ultrasound or computed tomography) while receiving VAD support, which demonstrated enlarged echogenic kidneys. These children had coagulation parameters within recommended ranges. These children subsequently died and autopsy studies of two children showed multiple bilateral kidney infracts, parenchymal congestion, and arterial thrombosis. Our case series shows that enlarged and echogenic kidneys may be associated with thromboembolism of the renal artery in pediatric patients on VAD. We were not able to identify a specific cause-and-effect relationship.
A Simplified Approach to Pediatric Modified Ultrafiltration: A Novel Circuit Design
Authors: Forsberg Brian C. , Novick William M.
Published: July 2023

A simple intuitive approach to modified ultrafiltration (MUF) may improve the safety of this technique and enhance the adoption rate of MUF in pediatric and adult centers. This simplified technique is more easily implemented than the traditional MUF technique and will allow teams to adopt this technique successfully with ease.
Meaningful Outcome Measures in Cardiac Surgery
Authors: Myles Paul S.
Published: July 2023

The most common cardiac surgical procedures are coronary artery bypass graft surgery and aortic or mitral valve repair or replacement. Underlying conditions include coronary artery disease and heart failure, manifesting as exertional angina, dyspnea, and poor exercise tolerance. The major goals of surgery are to alleviate symptoms and improve patient survival. These, therefore, should inform the choice of primary outcome measures in clinical studies enrolling patients undergoing cardiac surgery. Studies focusing on surrogate outcome measures are relied on all too often. Many are of questionable significance and often have no convincing relationship with patient outcome. Traditional “hard endpoint” outcome measures include serious complications and death with the former including myocardial infarction (MI) and stroke. Such serious adverse outcomes are commonly collected in registries, but because they occur infrequently, they need to be large to reliably detect true associations and treatment effects. For this reason, some investigators combine several outcomes into a single composite endpoint. Cardiovascular trials commonly use major adverse cardiac events (MACEs) as a composite primary endpoint. However, there is no standard definition for MACE. Most include MI, stroke, and death; others include rehospitalization for heart failure, revascularization, cardiac arrest, or bleeding complications. An influential trial in noncardiac surgery found that perioperative β-blockers reduced the risk of MI but increased the risk of stroke and death. Such conflicting findings challenge the veracity of such composite endpoints and raise a far more important question: which of these endpoints, or even others that were unmeasured, are most important to a patient recovering from surgery? Given the primary aims of cardiac surgery are to relieve symptoms and improve good quality survival, it is disability-free survival that is the ultimate outcome measure. The question then becomes: what is disability and how should it be quantified after cardiac surgery?
Quality Improvement Methodologies Increase Autologous Blood Product Administration
Authors: Hodge Ashley B. , Preston Thomas J. , Fitch Jill A. , Harrison Sheilah K. , Hersey Diane K. , Nicol Kathleen K. , Naguib Aymen N. , McConnell Patrick I. , Galantowicz Mark
Published: July 2023

Whole blood from the heart–lung (bypass) machine may be processed through a cell salvaging device (i.e., cell saver [CS]) and subsequently administered to the patient during cardiac surgery. It was determined at our institution that CS volume was being discarded. A multidisciplinary team consisting of anesthesiologists, perfusionists, intensive care physicians, quality improvement (QI) professionals, and bedside nurses met to determine the challenges surrounding autologous blood delivery in its entirety. A review of cardiac surgery patients’ charts (n = 21) was conducted for analysis of CS waste. After identification of practices that were leading to CS waste, interventions were designed and implemented. Fishbone diagram, key driver diagram, Plan–Do–Study–Act (PDSA) cycles, and data collection forms were used throughout this QI process to track and guide progress regarding CS waste. Of patients under 6 kg (n = 5), 80% had wasted CS blood before interventions, whereas those patients larger than 36 kg (n = 8) had 25% wasted CS before interventions. Seventy-five percent of patients under 6 kg who had wasted CS blood received packed red blood cell transfusions in the cardiothoracic intensive care unit within 24 hours of their operation. After data collection and didactic education sessions (PDSA Cycle I), CS blood volume waste was reduced to 5% in all patients. Identification and analysis of the root cause followed by implementation of education, training, and management of change (PDSA Cycle II) resulted in successful use of 100% of all CS blood volume.
Comparison of Routine Laboratory Measures of Heparin Anticoagulation for Neonates on Extracorporeal Membrane Oxygenation
Authors: Sulkowski Jason P. , Preston Thomas J. , Cooper Jennifer N. , Duffy Victoria L. , Deans Katherine J. , Chicoine Louis G. , Minneci Peter C.
Published: July 2023

Our objective was to determine the best measure of heparin anticoagulation in neonatal patients on extracorporeal membrane oxygenation. Activated clotting time (ACT), activated partial thromboplastin time (aPTT), and antifactor Xa levels, along with corresponding heparin infusion rates and heparin bolus volumes, were collected from neonates receiving ECMO at our institution from 2008 to 2013. After natural log transformation of antifactor Xa, ACT, and aPTT, overall correlations between antifactor Xa levels and either ACT or aPTT and correlations between these tests and heparin infusion rates were evaluated using linear mixed models that accounted for both within- and between-patient correlations. Twenty-six neonates with an average weight of 3.4 kg (standard deviation .7) had a total of 27 separate ECMO runs during the study period. Within each patient, ACT (r= .40,p< .0001) and aPTT (r= .48,p< .0001) were both directly correlated with antifactor Xa levels. In contrast, between patients, only aPTT maintained a direct correlation with antifactor Xa (r= .61,p= .07), whereas ACT showed a statistically significant inverse correlation with antifactor Xa (r= −.48,p= .04). Compared with ACT, aPTT is more consistently reflective of the anticoagulation status both within each patient on ECMO and between patients treated with ECMO. Future efforts to develop standardized heparin infusion algorithms for patients on ECMO should consider using aPTT levels to monitor anticoagulation.