Contemporary Trends and Risk Factors of Hemodynamic and Myocardial Mechanics Derived by the Pressure Recording Analytical Method After Pediatric Cardiopulmonary Bypass

Cardiovascular Effects of Tourniquet Application with Cardiac Cycle Efficiency: A Prospective Observational Study

Objectives: The impact of the tourniquet on cardiac efficiency remains unknown. This study aimed to assess the impact of the tourniquet on cardiac cycle efficiency (CCE) and to interpret how general anesthesia (GA) or combined spinal epidural anesthesia (CSEA) affects this during surgery using cardiac energy parameters. Methods: This prospective observational study included 43 patients undergoing elective unilateral total knee arthroplasty (TKA) with a tourniquet divided into GA (n = 22) and CSEA (n = 21) groups. Cardiac energy parameters were measured before anesthesia (T1), pre-tourniquet inflation (T2), during inflation (T3-T8), and post-deflation (T9). The estimated power of the study was 0.99 based on the differences and standard deviations in CCE at T2-T3 for all patients (effect size: 0.88, alpha error: 0.05). Results: CCE decreased significantly more at T3 in the GA group than in the CSEA group, whereas dP/dtmax and Ea increased more (p < 0.05, p < 0.001, and p < 0.01, respectively). At T9, CCE increased significantly in the GA group, whereas dP/dtmax and Ea decreased (p < 0.05, p < 0.001, and p < 0.001, respectively). Conclusions: The tourniquet reduces cardiac efficiency through compensatory responses, and CSEA may mitigate this effect.

The evaluation of cardiac functions in deep Trendelenburg position during robotic-assisted laparoscopic prostatectomy

Objective

This study aimed to demonstrate the reliability of the cardiac cycle efficiency value through its correlation with longitudinal strain by observing the effect of the deep Trendelenburg position.

Design

A prospective, observational study.

Setting

Single center.

Participants

Between May and September 2022, the hemodynamic parameters of 30 patients who underwent robotic assisted laparoscopic prostatectomy under general anesthesia were prospectively evaluated.

Measurements and main results

All invasive cardiac monitoring parameters and longitudinal strain achieved transesophageal echocardiography were recorded in pre-deep Trendelenburg position (T3) and 10th minute of deep Trendelenburg position (T4). Delta values were calculated for the cardiac cycle efficiency and longitudinal strain (values at T4 minus values at T3). The estimated power was calculated as 0.99 in accordance with the cardiac cycle efficiency values at T3 and T4 (effect size: 0.85 standard deviations of the mean difference: 0.22, alpha: 0.05). At T4, heart rate, pulse pressure variation, cardiac cycle efficiency, dP/dt and longitudinal strain were significantly lower than those at T3 (p = 0.009, p < 0.001, p < 0.001, and p < 0.001, respectively). There was a positive correlation between the delta-cardiac cycle efficiency and delta-longitudinal strain (R2 = 0.36, p < 0.001).

Conclusion

Although the absence of significant changes in mean arterial pressure and cardiac index after Trendelenburg position suggests that cardiac workload has not changed, changes in cardiac cycle efficiency and longitudinal strain indicate increased cardiac workload due to increased ventriculo-arterial coupling.

Cerebral Autoregulation Status in Relation to Brain Injury on Electroencephalogram and Magnetic Resonance Imaging in Children Following Cardiac Surgery

Background Disturbed cerebral autoregulation has been reported in children with congenital heart disease before and during cardiopulmonary bypass surgery, but not after. We sought to characterize the cerebral autoregulation status in the early postoperative period in relation to perioperative variables and brain injuries. Methods and Results A prospective and observational study was conducted in 80 patients in the first 48 hours following cardiac surgery. Cerebral oximetry/pressure index (COPI) was retrospectively calculated as a moving linear correlation coefficient between mean arterial blood pressure and cerebral oxygen saturation. Disturbed autoregulation was defined as COPI >0.3. Correlations of COPI with demographic and perioperative variables as well as brain injuries on electroencephalogram and magnetic resonance imaging and early outcomes were analyzed. Thirty-six (45%) patients had periods of abnormal COPI for 7.81 hours (3.38 hours) either at hypotension (median <45 mm Hg) or hypertension (median >90 mm Hg) or both. Overall, COPI became significantly lower over time, suggesting improved autoregulatory status during the 48 postoperative hours. All of the demographic and perioperative variables were significantly associated with COPI, which in turn was associated with the degree of brain injuries and early outcomes. Conclusions Children with congenital heart disease following cardiac surgery often have disturbed autoregulation. Cerebral autoregulation is at least partly the underlying mechanism of brain injury in those children. Careful clinical management to manipulate the related and modifiable factors, particularly arterial blood pressure, may help to maintain adequate cerebral perfusion and reduce brain injury early after cardiopulmonary bypass surgery. Further studies are warranted to determine the significance of impaired cerebral autoregulation in relation to long-term neurodevelopment outcomes.

The predictive value of pressure recording analytical method for the duration of mechanical ventilation in children undergoing cardiac surgery with an XGBoost-based machine learning model

Objective

Prolonged mechanical ventilation in children undergoing cardiac surgery is related to the decrease in cardiac output. The pressure recording analytical method (PRAM) is a minimally invasive system for continuous hemodynamic monitoring. To evaluate the postoperative prognosis, our study explored the predictive value of hemodynamic management for the duration of mechanical ventilation (DMV).

Methods

This retrospective study included 60 infants who underwent cardiac surgery. Cardiac index (CI), the maximal slope of systolic upstroke (dp/dt_max), and cardiac cycle efficiency (CCE) derived from PRAM were documented in each patient 0, 4, 8, and 12 h (T0, T1, T2, T3, and T4, respectively) after their admission to the intensive care unit (ICU). A linear mixed model was used to deal with the hemodynamic data. Correlation analysis, receiver operating characteristic (ROC), and a XGBoost machine learning model were used to find the key factors for prediction.

Results

Linear mixed model revealed time and group effect in CI and dp/dt_max. Prolonged DMV also have negative correlations with age, weight, CI at and dp/dt_max at T2. dp/dt_max outweighing CI was the strongest predictor (AUC of ROC: 0.978 vs. 0.811, p < 0.01). The machine learning model suggested that dp/dt_max at T2 ≤ 1.049 or < 1.049 in combination with CI at T0 ≤ 2.0 or >2.0 can predict whether prolonged DMV (AUC of ROC = 0.856).

Conclusion

Cardiac dysfunction is associated with a prolonged DMV with hemodynamic evidence. CI measured by PRAM immediately after ICU admission and dp/dt_max 8h later are two key factors in predicting prolonged DMV.

Incidence, risk factors, and outcomes in electroencephalographic seizures after mechanical circulatory support: A systematic review and meta-analysis

Purpose

To estimate the overall incidence, risk factors, and clinical outcomes of electroencephalographic (EEG) seizures for adults and children after mechanical circulatory support (MCS).

Method and measurements

This systematic review and meta-analysis were carried out in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidance document. MEDLINE EMBASE and CENTRAL were investigated for relevant studies. The related information was retrieved by two independent reviewers and all analyses were conducted by STATA (version 16.0; Stata Corporation, College Station, TX, United States).

Result

Sixty studies including 36,191 adult and 55,475 pediatric patients with MCS were enrolled for evaluation. The study showed that the overall incidence of EEG seizures in adults was 2% (95%CI: 1–3%), in which 1% (95%CI: 1–2%) after cardiopulmonary bypass (CPB), and 3% (95%CI: 1–6%) after extracorporeal membrane oxygenation (ECMO). For pediatrics patients, the incidence of EEG seizures was 12% (95%CI: 11–14%), among which 12% (9–15%) after CPB and 13% (11–15%) after ECMO. The major risk factors of EEG seizures after MCS in adults were redo surgery (coefficient = 0.0436, p = 0.044), and COPD (coefficient = 0.0749, p = 0.069). In addition, the gestational week of CPB (coefficient = 0.0544, p = 0.080) and respiratory failure of ECMO (coefficient = –0.262, p = 0.019) were also indicated to be associated with EEG seizures in pediatrics.

Conclusion

EEG seizures after MCS were more common in pediatrics than in adults. In addition, the incidence of EEG seizure after ECMO was higher than CPB both in adults and children. It is expected that appropriate measures should be taken to control modifiable risk factors, thus improving the prognosis and increasing the long-term survival rate of MCS patients.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero], identifier [CRD42021287288].