L-carnitine decreases myocardial injury in children undergoing open-heart surgery: A randomized controlled trial.

Myocardial injury in open-heart surgery is related to several factors including ischemia-reperfusion injury, generation of reactive oxygen species, increased production of inflammatory mediators, and enhancement of apoptosis of cardiomyocytes. The aim of this study was to study the effect of L-carnitine on myocardial injury in children undergoing open-heart surgery. This clinical trial was performed on 60 children with congenital heart disease (CHD) who underwent open-heart surgery. They were randomized into two groups: L-carnitine group who received L-carnitine 50 mg\kg\day once daily for 1 month before cardiac surgery and control group who received placebo for 1 month before cardiac surgery. Left ventricular cardiac function was assessed by conventional echocardiography to measure left ventricular ejection fraction (LVEF) and two-dimensional speckle tracking echocardiography (2D-STE) to determine left ventricular global longitudinal strain (2D-LV GLS). Blood samples were obtained pre-operatively at baseline before the administration of L-carnitine or placebo and 12 h post-operatively to measure the level of malondialdehyde (MDA), superoxide dismutase (SOD), fas, caspase-3, creatinine kinase-MB (CK-MB), and troponin I. L-carnitine group had significantly lower post-operative level of oxidative stress marker (MDA), apoptosis markers (fas and caspase-3), and myocardial injury markers (CK-MB and troponin I), but they had significantly higher SOD post-operative level compared to the control group. In addition, post-operative LVEF and 2D-LVGLS were significantly lower in the control group compared to L-carnitine group.   Conclusion: L-carnitine can reduce myocardial injury, improve post-operative left ventricular cardiac function, and may provide myocardium protection in children with CHD who underwent open-heart surgery.   Trial registration: The clinical trial was registered at www.pactr.org with registration number PACTR202010570607420 at 29/10/2020 before recruiting the patients. What is Known: • Myocardial injury in open-heart surgery is related to several factors including ischemia-reperfusion injury, generation of reactive oxygen species, increased production of inflammatory mediators, and enhancement of apoptosis of cardiomyocytes. • L-carnitine was reported to have myocardial protective effects in rheumatic valvular surgery and coronary artery bypass graft (CABG) in adults; however, there is no evidence on its effectiveness in children undergoing open-heart surgery. What is New: • L-carnitine significantly lowered the post-operative level of oxidative stress marker (MDA), apoptosis markers (fas and caspase-3), and myocardial injury markers (CK-MB and troponin I) in the treatment group. • L-carnitine can reduce myocardial injury, improve post-operative left ventricular cardiac function, and may provide myocardium protection in children with CHD who underwent open-heart surgery.

Pre-operative ultrasonographic evaluation of inferior vena cava collapsibility index and caval aorta index as new predictors for hypotension after induction of spinal anaesthesia: A prospective observational study.

BACKGROUND: Hypotension after spinal anaesthesia is a common side effect that may be harmful. Patients' susceptibility to intra-operative hypotension can be affected by many pre-operative factors. OBJECTIVES: The current study aimed to evaluate the efficacy of both pre-operative inferior vena cava collapsibility index (IVCCI) and inferior vena cava to aorta diameter (IVC : Ao) index for predicting postspinal anaesthesia hypotension (PSAH). DESIGN: Prospective observational blinded study. SETTING: Operating room from June 2017 to February 2018. PATIENTS: One hundred adult patients of both sexes, American Society of Anesthesiologists' physical status 1 or 2 scheduled for elective surgery under spinal anaesthesia were included in this study. INTERVENTIONS: Patients received spinal anaesthesia performed at the level of L3 to 4 or L4 to 5 intervertebral space with the patient in the sitting position then placed in the supine position immediately after neuraxial block and kept supine throughout the study period (30 min). IVCCI and IVC : Ao index were assessed pre-operatively. Baseline noninvasive blood pressure was recorded before administration of spinal anaesthesia then every minute after spinal blockade for 30 min. MAIN OUTCOME MEASURES: The primary outcome was to evaluate the predictive values of both IVCCI and IVC : Ao index for detecting PSAH and the secondary outcomes were to compare the predictive values of both IVCCI and IVC : Ao index and to detect other clinical predictors for PSAH using logistic regression analysis. RESULTS: Forty-five patients developed PSAH (45%). IVCCI was significantly higher in patients who developed PSAH than in patients who did not, while IVC : Ao index was significantly lower in patients who developed PSAH than in patients who did not. Hypotension after induction of spinal anaesthesia was defined as an absolute value of SBP less than 90 mmHg, a decrease in SBP more than 30% of the baseline value or an absolute value of arterial blood pressure less than 60 mmHg. Logistic regression analysis revealed that IVCCI and IVC : Ao index were good predictors of the occurrence of PSAH. Receiver operating characteristic curve analysis showed that IVC : Ao index had a sensitivity of 96%, a specificity of 88%, and an accuracy of 95% to predict PSAH at a cut-off point less than 1.2. IVCCI had a sensitivity of 84%, a specificity of 77%, and an accuracy of 84% to predict PSAH at a cut-off point more than 44.7%. CONCLUSION: Pre-operative IVCCI and IVC : Ao index are good predictors of the occurrence of PSAH. However, IVC : Ao index is a more powerful predictor than IVCCI.