Animal models for partial heart transplantation.

BACKGROUND: Partial heart transplantation delivers growing heart valve implants by transplanting the part of the heart containing the necessary heart valve only. In contrast to heart transplantation, partial heart transplantation spares the native ventricles. This has important implications for partial heart transplant biology, including the allowable ischemia time, optimal graft preservation, primary graft dysfunction, immune rejection, and optimal immunosuppression. AIMS: Exploration of partial heart transplant biology will depend on suitable animal models. Here we review our experience with partial heart transplantation in rodents, piglets, and non-human primates. MATERIALS & METHODS: This review is based on our experience with partial heart transplantation using over 100 rodents, over 50 piglets and one baboon. RESULTS: Suitable animal models for partial heart transplantation include rodent heterotopic partial heart transplantation, piglet orthotopic partial heart transplantation, and non-human primate partial heart xenotransplantation. DISCUSSION: Rodent models are relatively cheap and offer extensive availability of research tools. However, rodent open-heart surgery is technically not feasible. This limits rodents to heterotopic partial heart transplant models. Piglets are comparable in size to children. This allows for open-heart surgery using clinical grade equipment for orthoptic partial heart transplantation. Piglets also grow rapidly, which is useful for studying partial heart transplant growth. Finally, nonhuman primates are immunologically most closely related to humans. Therefore, nonhuman primates are most suitable for studying partial heart transplant immunobiology and xenotransplantation. CONCLUSIONS: Animal research is a privilege that is contingent on utilitarian ethics and the 3R principles of replacement, reduction and refinement. This privilege allows the research community to seek fundamental knowledge about partial heart transplantation, and to apply this knowledge to enhance the health of children who require partial heart transplants.

Improving Outcomes in Pulmonary Vein Stenosis: Novel Pursuits and Paradigm Shifts.

Pulmonary vein stenosis (PVS) remains a clinical challenge, with progressive restenosis being common. In the past five years, we have seen an exponential increase in both clinical and scientific publication related to PVS. Central to progress in PVS clinical care is the paradigm shift towards collaborative, multidisciplinary care that utilizes a multimodality approach to treatment. This manuscript will discuss recent conceptual gains in PVS treatment and research while highlighting important outstanding questions and barriers.

Long-Term Outcomes of Mechanical Aortic Valve Replacement in Children.

When the options of aortic valve repair or the Ross procedure are not feasible or have been exhausted, mechanical aortic valve replacement (AVR) may provide a reliable and structurally durable alternative, but with the limitations of long-term anticoagulation, thrombosis risk and lack of valve growth potential. In this article, we review the longitudinal outcomes of mechanical AVR in children in our institution and compare them to those recently reported by others. From 1978 to 2020, 62 patients underwent mechanical AVR at a median age of 12.4 years (interquartile range (IQR): 8.6-16.8 years). The most common underlying diagnoses were: conotruncal anomalies (40%, 25/62), congenital aortic stenosis (16%, 10/62), rheumatic valve disease (16%, 10/62), connective tissue disease (8.1%, 5/62) and infective endocarditis (6.5%, 4/62). Thirty-two patients (52%, 32/62) had at least 1 prior aortic valve surgery prior to mechanical AVR. Early death was 3.2% (2/62). Median follow-up was 14.4 years (IQR: 8.4-28.2 years). Kaplan-Meier survival was 96.8%, 91.9%, 86.3%, and 81.9% at 1, 5, 10, and 20 years. On competing risk analysis, the proportion of patients alive without aortic valve reoperation at 1, 5, 10, and 20 years was 95.2%, 87.0%, 75.5% and 55.4%, respectively, while the proportion of patients that had aortic valve reoperation (with death as a competing event) at 1, 5, 10, and 20 years was 1.6%, 4.9%, 12.8%, and 28.5%, respectively. In conclusion, when the options of aortic valve repair or the Ross procedure are not feasible in children, mechanical AVR is an alternative, yet the long-term rates of mortality and need for aortic valve reoperation are of concern.

Impact of Blood Sampling Methods on Blood Loss and Transfusion After Pediatric Cardiac Surgery: An Observational Study.

OBJECTIVES: The aims of this study were to assess the impact of the closed-loop sampling method on blood loss and the need for blood transfusion in pediatric patients following cardiac surgery. DESIGN: Retrospective observational study. SETTING: A single tertiary center. PARTICIPANTS: All pediatric patients younger than 4 years old who were admitted to the pediatric intensive care unit (PICU) after cardiac surgery were enrolled. The study included 100 pediatric patients in the conservative (postimplementation) group and 43 pediatric patients in the nonconservative group (preimplementation). INTERVENTIONS: Observational. MEASUREMENTS: The primary outcome was the volume of blood loss during the PICU follow-up period. The secondary outcomes were the requirement for blood transfusion in each group, duration of mechanical ventilation, length of intensive care unit (ICU) stay, length of hospital stay, and mortality. MAIN RESULTS: In the conservative (postimplementation) group, blood loss during the follow-up period was 0.67 (0.33-1.16) mL/kg/d, while it was 0.95 (0.50-2.30) mL/kg/d in the nonconservative (preimplementation) group, demonstrating a significant reduction in blood loss in the conservative group (p = 0.012). The groups showed no significant differences in terms of the required blood transfusion volume postoperatively during the first 24 hours, first 48 hours, or after 48 hours (p = 0.061, 0.536, 0.442, respectively). The frequency of blood transfusion was comparable between the groups during the first 24 hours, first 48 hours, or after 48 hours postoperatively (p = 0.277, 0.639, 0.075, respectively). In addition, the groups did not show significant differences in the duration of mechanical ventilation, length of ICU stay, length of hospital stay, or mortality. CONCLUSIONS: The closed-loop sampling method can be efficient in decreasing blood loss during postoperative PICU follow-up for pediatric patients after cardiac surgeries. However, its application did not reduce the frequency or the volume of blood transfusion in these patients.

Comparison of Multiple Injection Costotransverse Block and Erector Spinae Plane Block for Post-Sternotomy Pain Relief in Pediatric Patients Undergoing Cardiac Surgery: A Prospective Randomized Comparative Study.

OBJECTIVE: The aim of this study was to evaluate the efficacy of ultrasound-guided multiple injection costotransverse block (MICB) and compare it with erector spinae plane block (ESPB) for poststernotomy pain relief in pediatric cardiac surgical patients. DESIGN: A prospective, randomized, double-blind, comparative study. SETTING: At a single institution tertiary referral cardiac center. PARTICIPANTS: A total of 90 children with acyanotic congenital heart disease requiring surgery via sternotomy. INTERVENTIONS: Children were allocated randomly to 1 of the 3 following groups: ESPB (group 1), MICB (group 2), or Control (group 3). Participants in groups 1 and 2 received 4 mg/kg of 0.2% ropivacaine for bilateral ultrasound-guided block after induction of anesthesia. Postoperatively, intravenous paracetamol was used for multimodal analgesia, and fentanyl/tramadol was used for rescue analgesia. MEASUREMENTS AND MAIN RESULTS: The modified objective pain score (MOPS) was evaluated at 0, 1, 2, 4, 6, 8, 10, and 12 hours postextubation. After all exclusions, 84 patients were analyzed. The MOPS score was found to be significantly lower in ESPB and MICB groups compared to the control group until 10 hours postextubation (p < 0.05), with no statistically significant difference at the 12th hour (p = 0.2198). The total intraoperative fentanyl consumption (p = 0.0005), need for fentanyl supplementation on incision (p < 0.0001), and need for rescue opioid requirement in the postoperative period (p = 0.034) were significantly lower in both the ESPB and MICB groups than the control group. There were no statistically significant differences in both primary and secondary outcomes between the ESPB and MICB groups. CONCLUSION: Ultrasound-guided MICB was effective and comparable to ESPB for post-sternotomy pain management in pediatric cardiac surgical patients.

Effects of Fibrinogen Concentrate Supplementation on Postoperative Bleeding in Infants Undergoing Complex Cardiac Surgery.

The use of allogeneic blood products to restore hemostasis during pediatric cardiac surgery is associated with major risks. Consequently, there has been a growing interest in new patient blood management strategies, such as those based on the use of fibrinogen concentrate (FC). Accumulating evidence has shown FC supplementation to be safe and effective. Nevertheless, no guidelines are available on using FC in the pediatric setting, and few objective evaluations have been provided in clinical practice. The endpoint of this monocenter retrospective study was the hemostatic effect of additional FC in infants undergoing complex cardiac surgery with cardiopulmonary bypass to manage persistent clinically relevant bleeding. After weaning from cardiopulmonary bypass and after protamine administration, patients were transfused with conventional allogeneic products such as packed red blood cells, fresh frozen plasma (FFP), and platelets. In the case of redo surgery, according to the institutional protocol, patients also received tranexamic acid. In case of clinically persistent relevant bleeding, according to the anesthesiologist's judgment and thromboelastography, patients received FC supplementation (group with FC) or further FFP transfusions without receiving FC supplementation (group without FC). The primary endpoint was the hemostatic effects of FC. Secondary endpoints were the functional hypofibrinogenemia threshold value (expressed as maximum amplitude fibrinogen, MA-Fib) and postoperative MA-Fib, fibrinogenemia, intraoperative transfusions, and adverse events (AEs). In total, 139 patients who underwent cardiac surgery with CPB and aged less than 2 years were enrolled: 70 patients received allogeneic blood products and FC supplementation (group FC); 69 patients received allogeneic products without FC supplementation (group without FC). Patients that received FC supplementation were characterized by a significantly longer time of extracorporeal circulation (p < 0.001) and aortic cross-clamping (p < 0.001), a significantly lower minimum temperature (p = 0.011), increased use of concentrated prothrombin complex (p = 0.016) and tranexamic acid (p = 0.010), and a significantly higher amount of packed red blood cells, platelets (p < 0.001) and fresh frozen plasma (p = 0.03). Postoperative bleeding and severe bleeding were not statistically different between patients treated with FC and those not treated with FC supplementation (p = 0.786 and p = 0.695, respectively); after adjustment, a trend toward reduced bleeding can be observed with FC (p = 0.064). Overall, 88% of patients with severe bleeding had MA-Fib < 10 mm; a moderate association between severe bleeding and MA-Fib (odds ratio 1.7, 95% CI 0.5-6.5, p = 0.425) was found. Increased MA-Fib and postoperative fibrinogen were higher in the FC group (p = 0.003 and p < 0.001, respectively) than in FFP. AEs in the FC group were comparable to those observed in less complicated surgeries. Our results suggest a potential role of FC in complex surgery in maintaining postoperative bleeding at a level comparable to less complicated surgical procedures and favoring the increase in postoperative MA-Fib and fibrinogen.

Development and Validation of a Nomogram for Predicting Acute Kidney Injury in Pediatric Patients Undergoing Cardiac Surgery.

Acute kidney injury (AKI) is a common complication after cardiac surgery and associated with adverse outcomes. The purpose of this study is to construct a nomogram to predict the probability of postoperative AKI in pediatric patients undergoing cardiac surgery. We conducted a single-center retrospective cohort study of 1137 children having cardiac surgery under cardiopulmonary bypass. We randomly divided the included patients into development and validation cohorts at a ratio of 7:3. The least absolute shrinkage and selection operator regression model was used for feature selection. We constructed a multivariable logistic regression model to select predictors and develop a nomogram to predict AKI risk. Discrimination, calibration and clinical benefit of the final prediction model were evaluated in the development and validation cohorts. A simple nomogram was developed to predict risk of postoperative AKI using six predictors including age at operation, cyanosis, CPB duration longer than 120 min, cross-clamp time, baseline albumin and baseline creatinine levels. The area under the receiver operator characteristic curve of the nomogram was 0.739 (95% CI 0.693-0.786) and 0.755 (95% CI 0.694-0.816) for the development and validation cohort, respectively. The calibration curve showed a good correlation between predicted and observed risk of postoperative AKI. Decision curve analysis presented great clinical benefit of the nomogram. This novel nomogram for predicting AKI after pediatric cardiac surgery showed good discrimination, calibration and clinical practicability.

Establishing a High-Quality Pediatric Cardiac Surgery Program in Post-Conflict Regions: A Model for Limited Resource Countries.

BACKGROUND: Congenital Heart Disease stands as a prominent cause of infant mortality, with notable disparities in surgical outcomes evident between high-income and low- to middle-income countries. OBJECTIVE: This study presents a collaborative partnership between a local governmental entity and an international private organization to establish a high-quality Pediatric Cardiac Surgery Program in a post-conflict limited resource country, Iraq. METHODS: A descriptive retrospective study analyzed pediatric cardiac surgery procedures performed by a visiting pediatric heart surgery team from October 2021 to October 2022, funded by the Ministry of Health (MOH). We used the STS-EACTS complexity scoring model (STAT) to assess mortality risks associated with surgical procedures. RESULTS: A total of 144 patients underwent 148 procedures. Infants comprised 58.3% of the patients. The most common anomalies included tetralogy of Fallot, ventricular septal defect, and various single ventricle categories, constituting 76% of the patient cohort. The overall surgical mortality rate was 4.1%, with an observed/expected surgical mortality rate of 1.1 (95% CI 0.5, 2.3). There was no significant difference between our observed surgical mortality in Category 2, 3, and 4 and those expected/reported by the STS-EACTS Database (p = 0.07, p = 0.72, and p = 0.12, respectively). The expenses incurred by the MOH for conducting surgeries in Iraq were lower than the alternative of sending patients abroad for the same procedures. CONCLUSION: The partnership model between a local public entity committed to infrastructure development and funding and an international private organization delivering clinical and training services can provide the foundation for building sustainable, high-quality in situ programs in upper-middle-income countries.

Pediatric cardiac surgery: machine learning models for postoperative complication prediction.

PURPOSE: Managing children undergoing cardiac surgery with cardiopulmonary bypass (CPB) presents a significant challenge for anesthesiologists. Machine Learning (ML)-assisted tools have the potential to enhance the recognition of patients at risk of complications and predict potential issues, ultimately improving outcomes. METHODS: We evaluated the prediction capacity of six models, ranging from logistic regression to support vector machine, using a dataset comprising 33 variables and 1364 subjects. The Area Under the Curve (AUC) and the F1 score served as the primary evaluation metrics. Our primary objectives were twofold: first, to develop an effective prediction model, and second, to create a user-friendly comprehensive model for identifying high-risk patients. RESULTS: The logistic regression model demonstrated the highest effectiveness, achieving an AUC of 83.65%, and an F1 score of 0.7296, with balanced sensitivity and specificity of 77.94% and 76.47%, respectively. In comparison, the comprehensive three-layer decision tree model achieved an AUC of 72.84%, with sensitivity (79.41%) comparable to more complex models. CONCLUSION: Our machine learning-assisted tools provide an additional perspective and enhance the predictive capabilities of traditional scoring methods. These tools can assist anesthesiologists in making well-informed decisions. Furthermore, we have successfully demonstrated the feasibility of creating a practical white-box model. The next steps involve conducting clinical validation and multicenter cross-validation. TRIAL REGISTRATION: NCT05537168.

Novel inflammatory mediator profile observed during pediatric heart surgery with cardiopulmonary bypass and continuous ultrafiltration.

BACKGROUND: Cardiopulmonary bypass (CPB) is associated with systemic inflammation, featuring increased levels of circulating pro-inflammatory cytokines. Intra-operative ultrafiltration extracts fluid and inflammatory factors potentially dampening inflammation-related organ dysfunction and enhancing post-operative recovery. This study aimed to define the impact of continuous subzero-balance ultrafiltration (SBUF) on circulating levels of major inflammatory mediators. METHODS: Twenty pediatric patients undergoing cardiac surgery, CPB and SBUF were prospectively enrolled. Blood samples were collected prior to CPB initiation (Pre-CPB Plasma) and immediately before weaning off CPB (End-CPB Plasma). Ultrafiltrate effluent samples were also collected at the End-CPB time-point (End-CPB Effluent). The concentrations of thirty-nine inflammatory factors were assessed and sieving coefficients were calculated. RESULTS: A profound increase in inflammatory cytokines and activated complement products were noted in plasma following CBP. Twenty-two inflammatory mediators were detected in the ultrafiltrate effluent. Novel mediators removed by ultrafiltration included cytokines IL1-Ra, IL-2, IL-12, IL-17A, IL-33, TRAIL, GM-CSF, ET-1, and the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2 and CXCL10. Mediator extraction by SBUF was significantly associated with molecular mass < 66 kDa (Chi2 statistic = 18.8, Chi2 with Yates' correction = 16.0, p < 0.0001). There was a moderate negative linear correlation between molecular mass and sieving coefficient (Spearman R = - 0.45 and p = 0.02). Notably, the anti-inflammatory cytokine IL-10 was not efficiently extracted by SBUF. CONCLUSIONS: CPB is associated with a burden of circulating inflammatory mediators, and SBUF selectively extracts twenty of these pro-inflammatory factors while preserving the key anti-inflammatory regulator IL-10. Ultrafiltration could potentially function as an immunomodulatory therapy during pediatric cardiac surgery. Trial registration ClinicalTrials.gov, NCT05154864. Registered retrospectively on December 13, 2021. https://clinicaltrials.gov/ct2/show/record/NCT05154864 .

Intraoperative Dexmedetomidine Improves the Outcome of Pediatric Cardiac Surgery: A One-Year Cohort Study.

Background: Pediatric cardiac surgery is associated with a high risk of mortality and morbidity. The aim of this study was to determine if intraoperative dexmedetomidine therapy could improve survival after pediatric cardiac surgery. Methods: We conducted a retrospective review of 1384 consecutive children who underwent pediatric cardiac surgery. Amongst these, 889 received dexmedetomidine therapy and 495 did not. All children were followed for 1 year. Their in-hospital and long-term outcomes were compared by multivariate logistic regression to minimize bias, and propensity-score matched adjustment was used. Results: Children who received dexmedetomidine had lower mortality during the 30-day postoperative period compared to children who did not (1.57% vs. 4.24%; adjusted hazard ratio [HR]: 0.448; 95% confidence interval [CI]: 0.219-0.916, p = 0.028), as well as after 1 year (2.36% vs. 6.67%; adjusted [HR]: 0.487; 95% [CI]: 0.274-0.867, p = 0.014). The two groups showed no significant differences in cardiovascular complications. Conclusions: Dexmedetomidine administered intraoperatively reduced 30-day and 1-year mortality in children undergoing pediatric cardiac surgery.

Intraoperative Transfusion of Autologous Blood Protects from Acute Kidney Injury after Pediatric Congenital Heart Surgery.

Background: Acute kidney injury (AKI) is a common complication after pediatric cardiac surgery. And autologous blood transfusion (ABT) is an important predictor of postoperative AKI. Unlike previous studies, which mainly focused on the correlation between ABT and AKI, the current study focuses heavily on the causal relationship between them, thus providing guidance for the treatment of patients during hospitalization to reduce the occurrence of AKI. Methods: A retrospective cohort of 3386 patients extracted from the Pediatric Intensive Care database was used for statistical analysis, multifactorial analysis, and causal inference. Characteristics that were correlated with ABT and AKI were categorized as confounders, instrumental variables, and effect modifiers, and were entered into the DoWhy causal inference model to determine causality. The calculated average treatment effect (ATE) was compared with the results of the multifactorial analysis. Results: The adjusted odds ratio (OR) for ABT volume was obtained by multifactorial analysis as 0.964. The DoWhy model refute test was able to indicate a causal relationship between ABT and AKI. Any ABT reduces AKI about 15.3%-18.8% by different estimation methods. The ATE regarding the amount of ABT was -0.0088, suggesting that every 1 mL/kg of ABT reduced the risk of AKI by 0.88%. Conclusions: Intraoperative transfusion of autologous blood can have a protective effect against postoperative AKI.

Toward More Granular Guidelines in AAOCA: Associating Anatomical Details With Specific Surgical Strategies.

Patients with anomalous aortic origin of a coronary artery (AAOCA) require imaging to clarify the multiple potential anatomic sites of obstruction (fixed or dynamic). Once repaired, the pathway of blood to the myocardium must not encounter: (1) intrinsic ostial stenosis, (2) obstruction from compression or distortion near the commissure or the intercoronary pillar, (3) stenosis where the artery exits the aortic wall (due to an acutely angled "take-off"), (4) compression due to a pathway between the great vessels, (5) stenosis or compression along an intramural course, or (6) compression due to an intramuscular (intraseptal/intraconal) course. Detailed anatomic evaluation of each of these locations allows the surgeon to select an appropriate repair strategy, and each of these abnormal anatomic features should be "matched" with a particular surgical correction. We speculate that the most common surgical repair, unroofing with or without tacking, is often inadequate, as in isolation, it may not allow for correction with a large orifice from the appropriate sinus, without an interarterial course. While the evidence base is insufficient to call these recommendations formal guidelines, these recommendations should serve as a basis for further validity testing, and ultimate evolution to more granular guidelines on AAOCA management.

Acute kidney injury after infant cardiac surgery: a comparison of pRIFLE, KDIGO, and pROCK definitions.

BACKGROUND: KDIGO and pRIFLE classifications are commonly used in pediatric acute kidney injury (AKI). As a novel AKI definition, pROCK considered the high variability of serum creatinine in children. This study aimed to compare the above three definitions for AKI in infants undergoing cardiac surgery. METHODS: We analyzed a clinical cohort of 413 infants undergoing cardiac surgery. AKI was defined and staged according to pRIFLE, KDIGO, and pROCK, respectively. Incidence differences and diagnostic agreement across definitions were assessed. The association between postoperative outcomes and AKI by each definition was investigated. RESULTS: Postoperative AKI was identified in 185 (44.8%), 160 (38.7%), and 77 (18.6%) patients according to pRIFLE, KDIGO, and pROCK, respectively. The agreement between pRIFLE and KDIGO was almost perfect (κ = 0.88), while there was only a slight agreement between pROCK and them. AKI by pROCK was independently associated with adverse outcomes (p = 0.003) and prolonged mechanical ventilation (p = 0.002). CONCLUSIONS: There were considerable differences in AKI incidence and staging among definitions. Compared with pRIFLE and KDIGO, AKI defined by pROCK was significantly reduced and better associated with postoperative adverse outcomes.

A simple-to-use nomogram for predicting prolonged mechanical ventilation for children after Ebstein anomaly corrective surgery: a retrospective cohort study.

BACKGROUND: Prolonged mechanical ventilation (PMV) after pediatric cardiac surgery imposes a great burden on patients in terms of morbidity, mortality as well as financial costs. Ebstein anomaly (EA) is a rare congenital heart disease, and few studies have been conducted about PMV in this condition. This study aimed to establish a simple-to-use nomogram to predict the risk of PMV for EA children. METHODS: The retrospective study included patients under 18 years who underwent corrective surgeries for EA from January 2009 to November 2021. PMV was defined as postoperative mechanical ventilation time longer than 24 hours. Through multivariable logistic regression, we identified and integrated the risk factors to develop a simple-to-use nomogram of PMV for EA children and internally validated it by bootstrapping. The calibration and discriminative ability of the nomogram were determined by calibration curve, Hosmer-Lemeshow goodness-of-fit test and receiver operating characteristic (ROC) curve. RESULTS: Two hundred seventeen children were included in our study of which 44 (20.3%) were in the PMV group. After multivariable regression, we obtained five risk factors of PMV. The odds ratios and 95% confidence intervals (CI) were as follows: preoperative blood oxygen saturation, 0.876(0.805,0.953); cardiothoracic ratio, 3.007(1.107,8.169); Carpentier type, 4.644(2.065,10.445); cardiopulmonary bypass time, 1.014(1.005,1.023) and postoperative central venous pressure, 1.166(1.016,1.339). We integrated the five risk factors into a nomogram to predict the risk of PMV. The area under ROC curve of nomogram was 0.805 (95% CI, 0.725,0.885) and it also provided a good discriminative information with the corresponding Hosmer-Lemeshow p values > 0.05. CONCLUSIONS: We developed a nomogram by integrating five independent risk factors. The nomogram is a practical tool to early identify children at high-risk for PMV after EA corrective surgery.

Indispensable Role of Transesophageal Echocardiography in Double-Chamber Right Ventricle Repair Surgery.

Double-chamber right ventricle repair surgery requires the excision of anomalous obstructive muscular or fibromuscular bundles in the right ventricular outflow tract. Because of the close proximity of key structures in the right ventricular outflow tract, the surgery is extremely challenging and requires precise resection. Underresection of the muscle bands can lead to significant residual gradients in the postoperative period, whereas overenthusiastic resection can cause iatrogenic injury to surrounding structures. Various techniques like Hegar sizing by the surgeons, direct chamber pressure measurement, transesophageal echocardiography, and epicardial echocardiography can guide the surgeons about the adequacy of repair. Transesophageal echocardiography is crucial at each step, as it can precisely determine the exact site of obstruction in the preoperative period. Postoperatively, it helps determine the adequacy of surgical repair and identification of inadvertent iatrogenic complications.

Association between regional oxygen saturation and central venous saturation in pediatric patients undergoing cardiac surgery: A prospective observational study.

BACKGROUND: We evaluated the correlation between regional oxygen saturation (rSO2 ) in the frontal and right renal dorsum (cerebral rSO2 and somatic rSO2 ) measured by near-infrared spectroscopy (INVOS™ 5100C, Medtronic) and central venous oxygen saturation (ScvO2 ) measured with a fiber-optic oximetry catheter (PediaSat™, Edwards Lifesciences) during surgery in order to determine whether noninvasive rSO2 could be used as an alternative to ScvO2 in pediatric cardiac surgery patients. We evaluated the correlation between regional tissue oxygen saturation (cerebral rSO2 and somatic rSO2 ) measured by near-infrared spectroscopy and other patient measures with central venous oxygen saturation (ScvO2 ) measured with a fiber-optic oximetry catheter to track global oxygen supply demand as a potential alternative or supplement to ScvO2 . PATIENTS AND METHODS: This single-center prospective observational study enrolled 33 children (weight < 10 kg) who underwent cardiac surgery for congenital heart disease between February 2018 and November 2021. ScvO2 , cerebral rSO2 , and somatic rSO2 were recorded simultaneously after anesthesia induction and central venous catheter placement. Pearson's correlation coefficient and Bland-Altman analysis were used to determine the relationship between ScvO2 and rSO2 . We conducted correlation, Bland Altman, and multiple regression analyses to identify associations between rSO2 , patient measures, and ScvO2 values. RESULTS: The patients' median age was 11.0 (quartile 2.0-16.0) months. Their weight was 7.2 (quartile 4.5-9.2) kg. Cerebral rSO2 was significantly positively correlated with ScvO2 (r2 = 0.29, p = .002 in all patients; r2 = 0.61, p = .013 in the patients without mixing at the atrial level), whereas somatic rSO2 was not. The Bland-Altman analysis demonstrated biases [95% confidence interval; 95% CI] (lower and upper limits of agreement [95% CI]) of 0.27% [-4.26 to 4.80] (-24.79 [-32.61 to -16.96] to 25.33 [17.50 to 33.16]) between cerebral rSO2 and ScvO2 and 0.91% [-5.48 to 7.30] (-34.43 [-45.47 to -23.39] to 36.25 [25.21 to 47.29]) between somatic rSO2 and ScvO2 . Preoperative brain natriuretic peptide (BNP) and SpO2 were independent variables associated with ScvO2 and cerebral and somatic rSO2 . CONCLUSION: Cerebral rSO2 , SpO2 , and BNP were significantly correlated with ScvO2 , although the cerebral rSO2 correlation was greater for lesions without atrial mixing. rSO2 , BNP, and SpO2 might be used to track changes in ScvO2 but cerebral rSO2 is not sufficiently precise to replace it.

Team Communication and Expectations Following Pediatric Cardiac Surgery: A Multi-Disciplinary Survey.

Patients and families desire an accurate understanding of the expected recovery following congenital cardiac surgery. Variation in knowledge and expectations within the care team may be under-recognized and impact communication and care delivery. Our objective was to assess knowledge of common postoperative milestones and perceived efficacy of communication with patients and families and within the care team. An 18-question survey measuring knowledge of expected milestones for recovery after four index operations and team communication in the postoperative period was distributed electronically to multidisciplinary care team members at 16 academic pediatric heart centers. Answers were compared to local median data for each respondent's heart center to assess accuracy and stratified by heart center role and years of experience. We obtained 874 responses with broad representation of disciplines. More than half of all respondent predictions (55.3%) did not match their local median data. Percent matching did not vary by care team role but improved with increasing experience (35.8% < 2 years vs. 46.4% > 10 years, p = 0.2133). Of all respondents, 62.7% expressed confidence discussing the anticipated postoperative course, 78.6% denoted confidence discussing postoperative complications, and 55.3% conveyed that not all members of their care team share a common expectation for typical postoperative recovery. Most respondents (94.6%) stated that increased knowledge of local data would positively impact communication. Confidence in communication exceeded accuracy in predicting the timing of postoperative milestones. Important variation in knowledge and expectations for postoperative recovery in pediatric cardiac surgery exists and may impact communication and clinical effectiveness.

'Are Routine Post-discharge Diuretics Necessary After Pediatric Cardiac Surgery?'

A prospective, one-armed, safety non-inferiority trial with historical controls was performed at a single-center, quaternary, children's hospital. Inclusion criteria were children aged 3 months-18 years after pediatric cardiac surgery resulting in a two-ventricle repair between 7/2020 and 7/2021. Eligible patients were compared with patients from a 5-year historical period (selected using a database search). The intervention was that "regular risk" patients received no diuretics and pre-specified "high risk" patients received 5 days of twice per day furosemide at discharge. 61 Subjects received the intervention. None were readmitted for pleural effusions, though 1 subject was treated for a symptomatic pleural effusion with outpatient furosemide. The study was halted after an interim analysis demonstrated that 4 subjects were readmitted with pericardial effusion during the study period versus 2 during the historical control (2.9% versus 0.2%, P = 0.003). We found no evidence that limited post-discharge diuretics results in an increase in readmissions for pleural effusions. This conclusion is limited as not enough subjects were enrolled to definitively show that this strategy is not inferior to the historical practice. There was a statistically significant increase in readmissions for pericardial effusions after implementation of this study protocol which can lead to serious complications and requires further study before conclusions can be drawn regarding optimal diuretic regimens.

Diagnostic Agreement Between TEG5000 and TEG6S in the Assessment of Hemostasis in Pediatric Cardiac Surgery: A Prospective Non-inferiority Study.

Thromboelastography (TEG) is a point-of-care test (POCT) used to analyze the hemostatic properties of whole blood. TEG® 5000and TEG® 6s (Haemonetics Corp, USA) measure the same parameters describing clot viscoelasticity using different methodologies. The purpose of this study was to evaluate agreement between TEG5000 and TEG6s measurements. We analyzed prospectively collected tests resulting from paired blood samples in cardiac surgery pediatric patients at one hour (T0) and 24 h (T1) postoperatively. Each citrated sample was utilized for TEG® 5000 and TEG ®6s. Six specific TEG parameters were analyzed and compared: R kaolin time (RK), R kaolin heparinase (RKH) time, K kaolin time (KK), K kaolin heparinase time KH (KKH), Maximum Amplitude kaolin (MAK), Maximal Amplitude Kaolin Heparinase (MAKH). We enrolled 30 patients. Median (interquartile range) patients' age was 206 (20-597) days. All surgical patients underwent correction except 5 who were palliated. At T0, RK and RKH showed an average (standard deviation) % bias of 15.8 (31) and 16.1 (28), respectively, with similar results at T1. A % bias of -6 (23) and - 6 [15] in MAK was found at T0 and T1, respectively. Similarly, MAKH % bias was 1.5 (22) and 7.6 (29) at T0 and T1, respectively. At both timepoints, low % biases (< ± 6%) were demonstrated in KK and KKH. All parameters showed improved coagulation from T0 to T1, but without significant interaction between type of device and time. Analysis of the entire pool of 60 paired samples showed no agreement in diagnostic performance (within the range vs. outside the range) in 12 (20%), 5 (9.8%), 1 (1.7%), 4 (7.8%), 9 (15%), and 5 (9.8%) cases for RK, RKH, MAK, MAKH, KK and KKH, respectively. We observed substantial agreement in MAK and KK in a cohort of pediatric patients undergoing uncomplicated cardiac surgery. Our findings suggest that TEG®5000 and TEG®6s are interchangeable for assessing these parameters.