Cardiac surgery-associated acute kidney injury (CSA-AKI) is one of the most frequent and severe complications after cardiac surgery. The association between acute kidney injury and the mismatch between oxygen consumption and delivery has been well established during cardiopulmonary bypass (CPB). In this study, we aim to explore the prognostic value of the central venous-to-arterial pCO2 gap during CPB to predict CSA-AKI. Bicentric retrospective study conducted in two teaching hospitals. All patients who underwent cardiac surgery requiring CPB in two periods between 2019 and 2023 were screened for inclusion. Patients were divided into 2 groups according to the presence or absence of an elevated pCO2 gap during CPB, which was defined as greater than 6 mmHg. The primary outcome was the occurrence of CSA-AKI. Among 318 patients included, 213 were in the low pCO2 gap group and 105 in the elevated pCO2 gap group. No significant difference in CSA-AKI occurrence was found between groups (32.4% vs. 23.8%; p = 0.14). pCO2 gap was not a good predictor of CSA-AKI, with an area under the curve for the ROC curve of 0.63 (p = 0.87). Except for SVO2 during CPB, we did not find any correlation between pCO2 gap and other tissue perfusion parameters during or after CPB. We did not find any association between the presence of an elevated pCO2 gap during CPB and the occurrence of CSA-AKI. This may suggest that a single intraoperative measurement of pCO2 gap is not a reliable marker of persistent tissue hypoperfusion in this context.

Effectiveness of intermittent pneumatic compression cushion in preventing sacrococcygeal intraoperative acquired pressure injuries during cardiac surgery: a randomized controlled trial.

Dabigatran in Sheep Cardiopulmonary Bypass: Reply.

Dabigatran in Sheep Cardiopulmonary Bypass: Comment.

Background: Sanguineous preparation of the cardiopulmonary bypass (CPB) circuit with allogeneic blood products is known to contain substantial complement mediator burden. This study aims to assess the longitudinal immunologic impacts during pediatric CPB. Methods: In this post-hoc analysis of a prospective observational cohort study, 40 pediatric patients undergoing cardiac surgery with CPB were grouped by CPB prime type indicated by standard of care (sanguineous vs crystalloid). Arterial samples were collected before CPB, after CPB initiation, and at 30-min intervals until weaning or 180 min. Luminex® measured concentrations of 33 inflammatory mediators for time series and fold change comparison between groups. Results: The sanguineous prime group (n = 26) was younger (4.0 [0.2-6.0] versus 48.5 [39.0-69.5] months; P < .001) and smaller (4.9 [3.4-6.6] versus 17.2 [14.9-19.6] kg; P < .001) than the crystalloid prime group (n = 14). The sanguineous group had significantly more circulating complement mediators, including C3a, C3b, and C5a, and soluble adhesion molecules throughout the CPB time series (P < .05). TNF, IL-1α, and IL-1β were relatively static in both groups, although slightly more prominent in the crystalloid group (P < .05). IL-6, IL-10, and CXCL8 profiles were comparable between groups. Conclusions: Patients who receive sanguineous CPB prime have elevated complement and soluble cellular adhesion molecule burden throughout CPB, relative to a crystalloid prime. Therefore, these allogeneic preparations should be considered an immunogenic stimulus during pediatric CPB, and future innovation should focus on less inciting alternatives.

Postoperative respiratory failure (PRF) is a severe complication after open-heart surgery, associated with increased mortality and prolonged ICU stays. While machine learning (ML) models have shown promise in predicting PRF, existing models often rely on fragmented data and lack interpretability. This study aimed to develop an interpretable ML model for early prediction of PRF using data from the first 24h of ICU admission. We analyzed data from the MIMIC-IV database, focusing on patients undergoing open-heart surgery with cardiopulmonary bypass (CPB). Patients with preoperative respiratory failure or significant missing data were excluded. Missing values (< 30%) were imputed using Predictive Mean Matching. Twelve features were selected through LASSO regression. We compared the performance of eight ML models using AUROC, AUPRC, and other metrics. The optimal model was further interpreted using Shapley Additive exPlanations (SHAP). Of the 4,488 patients, 339 (7.6%) developed PRF. The Gradient Boosting Machine (GBM) model demonstrated the best performance with an AUROC of 0.808, AUPRC of 0.369, and Youden's index of 0.479, indicating balanced sensitivity (0.703) and specificity (0.776). SHAP analysis revealed that key predictors included minimum ionized calcium levels, vasopressor score, and central venous oxygen saturation (ScvO₂), with their impact varying across patient risk categories. The GBM model, selected for its balanced performance across discrimination, calibration, and validation stability, provides a promising tool for early PRF risk stratification. The use of SHAP analysis enhances the interpretability of the model, highlighting the role of hemodynamic and metabolic markers in predicting PRF, thus improving clinical understanding and decision-making.

BackgroundPrimary tumors of the pulmonary artery are rare and frequently misdiagnosed as thromboembolic disease. Benign chondroid tumors arising from this location are exceptionally uncommon.Case DescriptionA 23-year-old man presented with exertional dyspnea and syncope. Imaging revealed a well-defined mass occupying the main pulmonary artery. Positron emission tomography/computed tomography showed no metabolic activity. The mass was completely excised under cardiopulmonary bypass. Histopathological examination demonstrated mature hyaline cartilage with low proliferative activity, consistent with a benign chondroid tumor. The postoperative course was uneventful, and no recurrence was observed at 12-month follow-up. This case highlights a rare benign etiology of pulmonary artery obstruction. Surgical resection remains the definitive diagnostic and therapeutic approach in selected patients with atypical intraluminal pulmonary artery masses.

Nutrition support practices in cardiothoracic surgery patients with gastrointestinal complications: An observational study.

The choice of a central venous catheter (CVC) lumen to connect the central venous pressure (CVP) measurement line varies by facility. However, if the CVP values differ based on the connected CVC lumen, this variation could significantly affect the interpretation of the CVP measurements, raising major concerns regarding circulatory management of the patient. This study aimed to determine whether a difference exists in the CVP values between the proximal and distal lumens of the CVC in small pediatric patients undergoing cardiac surgery. Seventeen pediatric patients with congenital heart disease, aged 1 to 31 months, who underwent cardiac surgery between November 2022 and November 2023, were included in this study. The CVC was inserted via the right internal jugular vein or right supraclavicular approach. Separate transducers were connected to the proximal and distal lumens. The CVP values from each were recorded simultaneously throughout the surgery. Differences were examined in the following phases: (1) after general anesthesia induction, (2) after initiation of cardiopulmonary bypass (CPB), and (3) after weaning from CPB. No statistically significant differences were observed in A-wave pressure, X-descent pressure, or mean CVP values measured from the distal and proximal lumens after general anesthesia induction or after weaning from CPB. The distal lumen showed significantly lower pressure than the proximal lumen after CPB initiation. Our findings revealed no significant difference in the CVP values between the proximal and distal lumens of the CVC in small pediatric patients; moreover, the proximal lumen provided reliable CVP values, even during CPB. These findings support connecting the CVP line to the proximal lumen, offering the great advantage of early detection of CVC slippage through changes in the CVP values and waveforms. This study was registered in the UMIN Clinical Trials Registry (registration number: UMIN000052944).

Transcervical Robotic Aortic Valve Replacement: A Possible New Frontier in Cardiac Surgery?

Intracardiac injuries caused by needles are rare and typically require removal via median sternotomy or limited thoracotomy. We present a case of successful removal using a totally endoscopic minimally invasive cardiac surgery (MICS) approach without cardiopulmonary bypass. A 57-year-old woman presented with chest discomfort one day after falling and striking her left chest. Chest computed tomography revealed a fractured sewing needle, with one fragment embedded in the left ventricular myocardium and the other in the subcutaneous tissue. The patient remained hemodynamically stable, and removal was performed using a totally endoscopic MICS approach was performed. The intracardiac fragment was removed endoscopically without bleeding. The subcutaneous portion was extracted via a small skin incision. The postoperative course was uneventful, and the patient was discharged on day 5. Totally endoscopic MICS without cardiopulmonary bypass may be a safe and effective option for removing intracardiac foreign bodies in carefully selected patients.

Re-operative management of a failing aortic homograft presents substantial technical challenges due to progressive calcification of the valve leaflets, annulus, coronary button attachments and surrounding aortic root structures. In this video tutorial, we demonstrate the explantation of a heavily calcified 21-mm aortic homograft and performance of a redo aortic root replacement using a handmade composite Bentall graft with a 25-mm bioprosthesis and 28-mm straight Dacron graft. A 73-year-old man, 23 years post-homograft root replacement, presented with torrential aortic regurgitation and a small, densely calcified aortic root. Following redo sternotomy and cardiopulmonary bypass initiation, the homograft was meticulously debrided with careful preparation of the coronary buttons, which required extensive decalcification. A composite graft was created with a tailored skirt to accommodate upsizing of the valve despite the small native annulus. Reimplantation of the left coronary button was performed, followed by distal aortic anastomosis. After removing the aortic cross-clamp, the anastomotic site of the right coronary button anastomosis was identified. The aorta was cross-clamped again, and the right coronary button was anastomosed.

The aim is to evaluate the transannular patch (TAP) repair and valve-sparing repair (VSR) techniques following tetralogy of Fallot (TOF) correction, focusing on post-operative complications and cardiac function. A comprehensive search was performed in PubMed, EMBASE, and Scopus using relevant terms like “Tetralogy of Fallot, right ventricular outflow tract (RVOT), VSR, pulmonary valve replacement, transannular-patch repair”. Results indicated that VSR is favored due to its shorter cardiopulmonary bypass duration, preservation of the pulmonary valve, less demanding surgical requirements, shorter post-operative hospital stays, lower mortality rates, survival of at least 30 years, reduced pulmonary regurgitation, decreased right ventricular dysfunction, and improved physical activity tolerance and neurodevelopment. While TAP alleviates RVOT obstruction (RVOTO), it is associated with long-term pulmonary regurgitation. Both TAP and VSR are effective in managing TOF, but VSR provides better valve function preservation and long-term outcomes.

Machine learning prediction model for delirium after heart valve replacement with cardiopulmonary bypass: A large-scale cohort study.

Abstract Background: The physiological benefits of pulsatile flow (PF) versus non-pulsatile flow (NPF) during cardiopulmonary bypass (CPB) remain debated, particularly regarding cerebral oxygenation, metabolic homeostasis, and systemic perfusion in adult cardiac surgery. Methods: In this prospective interventional crossover trial conducted at a tertiary cardiac centre, 112 adults undergoing elective cardiac surgery with CPB (February 2019–March 2020) were studied. Following aortic cross-clamping, PF and NPF were each applied for 20 minutes in random sequence, with every patient serving as their own control. Cerebral regional oxygen saturation (rSO 2 ) was continuously measured using near-infrared spectroscopy. Secondary outcomes included mean arterial pressure (MAP), arterial PaO 2 , PaCO 2 , pH, serum lactate, and bicarbonate (HCO 3 − ). Comparisons between flow modes were performed using paired analyses. Results: Mean rSO 2 during NPF (55.62 ± 5.42) was significantly higher than during PF (54.70 ± 5.73; P &lt; 0.05). Mean PaO 2 was also higher with NPF (259.81 ± 69.25 mmHg) compared with PF (244.75 ± 61.81 mmHg; P &lt; 0.001). Serum lactate levels were significantly greater during NPF ( P &lt; 0.001), whereas serum bicarbonate was significantly lower during NPF than PF ( P &lt; 0.05). No significant differences were observed in MAP, arterial pH, or PaCO 2 between the two flow patterns ( P &gt; 0.05). Conclusions: In adult patients undergoing CPB, NPF was associated with modestly higher cerebral rSO 2 and PaO 2 values but also higher lactate and lower bicarbonate levels compared with PF. MAP, pH, and PaCO 2 were comparable between strategies. These findings suggest measurable physiological differences between flow modalities; however, the clinical significance of these variations warrants further investigation. Trial registration: Clinical Trials Registry—India (CTRI/2019/01/017030).

Impact of continuous nursing care based on IKAP theory in patients undergoing cardiopulmonary bypass surgery: a cohort study.

Intra-operative hypotension is common during cardiopulmonary bypass and may contribute to tissue hypoxia. Tissue hypoxia has been linked to the development of postoperative kidney and brain injury. Vasopressors are used to treat hypotension during and after cardiopulmonary bypass. However, the effects of these drugs on renal and cerebral tissue oxygenation and perfusion are unknown. We tested the effects of four vasopressors on renal and cerebral tissue perfusion and oxygenation in a clinically-relevant ovine model of cardiopulmonary bypass. We studied 16 sheep before and after induction of anaesthesia and during 2.5 h of cardiopulmonary bypass. After commencing cardiopulmonary bypass at a target non-pulsatile flow of 2.4 l.min-1.m-2, we observed a baseline period with a target mean arterial pressure of 50-60 mmHg, after which we targeted a mean arterial pressure of 75-85 mmHg using a continuous infusion of metaraminol (n = 8); noradrenaline (n = 8); phenylephrine (n = 8); or vasopressin (n = 7). Sheep were allocated randomly to receive two of the four vasopressors. Compared with the pre-induction state, cardiopulmonary bypass significantly decreased renal medullary tissue perfusion (median (IQR [range]) decrease 55 (4-82 [1-99])%; p = 0.01) and medullary oxygen tension (mean (SD) difference 3.1 (2.5) kPa; p < 0.001). Cardiopulmonary bypass did not significantly alter cerebral tissue perfusion or oxygenation compared with the pre-induction state. Infusing noradrenaline significantly decreased medullary oxygen tension (mean (SD) difference 2.7 (1.6) kPa; p = 0.003). This decreasein medullary oxygen tension was significant compared with vasopressin (mean difference -3.4kPa, 95%CI -5.7 to -1.0; p = 0.008). No vasopressor infusion significantly altered renal medullary perfusion, cerebral tissue perfusion or oxygenation. Intra-operative noradrenaline during ovine cardiopulmonary bypass worsens renal medullary tissue oxygenation relative to vasopressin. These findings suggest that the choice of vasopressors may affect renal oxygenation.

The accuracy and precision of continuous in-line blood gas monitoring (CILBGM) are crucial for optimal blood gas management during cardiopulmonary bypass (CPB) and improved patient outcomes. CILBGM devices, such as the CDI 500/550 system, measure PaO2 and PaCO2, and B-Capta measures PaO2 through direct contact with arterial blood. However, the Quantum perfusion system with Quantum Ventilation2 (Quantum System) does not measure but calculates PaO2 and PaCO2 using several non-invasive sensors and proprietary formulas. We have observed that the calculated in-line PaO2 and PaCO2 values from Quantum System are frequently significantly higher than those obtained from iSTAT, a point-of-care blood analyzer, exceeding acceptable targets. We conducted a retrospective study involving 81 patients who underwent cardiac surgery using the Quantum System with its own CILBGM and the FX05 oxygenator. The aim was to identify the degree, timing, and possible patterns of error of the calculated in-line PaO2 and PaCO2. Our study showed that the errors of calculated in-line PaO2 exceed the acceptable target at the 1st blood gas series and during the rewarming and rewarmed periods, correlating with patient weight. The calculated in-line PaCO2 exhibited an upward drift during the rewarming period, correlating with the temperature gradient rather than patient weight. Based on several correlations identified, we derived a formula to predict FiO2 based on patient weight, which would achieve the target PaO2at the 1st blood gas series when using the FX05 oxygenator. We identified when and how the errors in calculating in-line PaO2 and PaCO2 occurred and developed several recommendations to minimize significant deviations from actual PaO2 and PaCO2 during CPB. Our results suggest that achieving acceptable PaO2 and PaCO2 calculations throughout CPB using a single universal formula for each, embedded in the Quantum System, is challenging due to the variety of oxygenators available, different patient sizes, and changing conditions during CPB.

Protamine is administered to reverse unfractionated heparin (UFH) after cardiopulmonary bypass (CPB), but dosing strategies-typically based on protamine-to-heparin (P:H) ratios-vary, and the minimal effective dose remains unclear. Reversal is commonly assessed using activated clotting time (ACT), which may not reliably reflect residual heparin activity. We used pharmacometric modeling to determine a minimal effective P:H ratio and to characterise the anti-factor Xa (anti-Xa) activity-ACT relationship. In this prospective, single-centre study, 68 adults undergoing CPB-assisted cardiac surgery were enrolled. A total of 757 blood samples were collected intraoperatively and after UFH reversal to measure anti-Xa activity and ACT. A population pharmacokinetic-pharmacodynamic model was developed using a nonlinear mixed-effects approach to describe UFH neutralisation by protamine. This model was then used to perform Monte Carlo simulations estimating the probability of complete reversal (anti-Xa <0.10 IU ml-1) at various P:H ratios, based on cumulative intraoperative UFH dose. Patients received a mean total dose of 30 250 IU UFH and 200 mg protamine i.v. Measured anti-Xa activity decreased to <0.10 IU ml-1 in all patients within 10 min of protamine initiation, indicating rapid reversal. Model-based simulations predicted that a P:H ratio of 0.625:1 would achieve complete reversal in 95% of patients. Although ACT and anti-Xa activity were positively associated, ACT values varied widely at low anti-Xa concentrations. A P:H ratio of 0.625:1 provided adequate UFH reversal. Given the imprecision of ACT, fixed low-ratio dosing without routine monitoring could be a practical alternative but requires prospective validation. EudraCT (2019-000859-14); www. gov (NCT04092868).

Pulmonary atresia with intact ventricular septum (PA-IVS) and myocardial dysfunction is a challenging entity to manage. Presented is a patient with PA-IVS who developed myocardial dysfunction and heart failure following an episode of periprocedural hypotension. He was successfully treated with a single ventricle assist device (SVAD) placed without cardiopulmonary bypass and a ductal stent as a bridge to donation after circulatory death heart transplant. This report describes the technique of SVAD placement without cardiopulmonary bypass.