Effect of Remote Ischemic Preconditioning on Troponin I in CABG

Evaluation of the Relationship Between Changes in Potassium Concentration and Arrhythmia During Coronary Artery Bypass Grafting Surgery

Background

Coronary artery bypass grafting (CABG) surgery is a treatment option for coronary artery diseases. Cardiac arrhythmias during CABG surgery can lead to serious complications. Potassium ion concentration is a factor involved in such arrhythmias.

Objectives

This study aimed to investigate the relationship between potassium concentration and cardiac arrhythmias in CABG surgery.

Methods

This descriptive cross-sectional study was performed on 60 patients with the American Society of Anesthesiologists class I, II, and III undergoing CABG surgery at Golestan Hospital, Ahvaz, Iran. All patients underwent general anesthesia, and ventilator control was achieved by mechanical ventilation. The on-pump method was used for CABG. Potassium levels were measured at several time points during surgery. All cardiac arrhythmias were recorded. Mean arterial pressure (MAP), serum level of potassium, blood sugar, blood urea nitrogen (BUN), creatinine, calcium, magnesium, hemoglobin (Hb), and sodium were also recorded.

Results

The mean age of the patients was 60.87 ± 7.35 years, and 45% of the subjects were female. Moreover, there was no statistically significant difference between the patients. There was a significant relationship between the changes in MAP, potassium, blood sugar, BUN, creatinine, calcium, and magnesium with the incidence of cardiac arrhythmias (P < 0.05). However, no significant relationship was noted between Hb and sodium levels with the incidence of cardiac arrhythmias (P < 0.05).

Conclusions

The changes in potassium levels increase the risk of cardiac arrhythmias and their complications.

Remote Ischemic Preconditioning Reduces Acute Kidney Injury After Cardiac Surgery: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Results from previous studies evaluating the effects of remote ischemic preconditioning (RIPC) on morbidity and mortality after cardiac surgery are inconsistent. This meta-analysis of randomized controlled trials (RCTs) aims to determine whether RIPC improves cardiac and renal outcomes in adults undergoing cardiac surgery.

METHODS

PubMed, EMBASE, and Cochrane Library were comprehensively searched to identify RCTs comparing RIPC with control in cardiac surgery. The coprimary outcomes were the incidence of postoperative myocardial infarction (MI) and the incidence of postoperative acute kidney injury (AKI). Meta-analyses were performed using a random-effect model. Subgroup analyses were conducted according to volatile only anesthesia versus propofol anesthesia with or without volatiles, high-risk patients versus non-high-risk patients, and Acute Kidney Injury Network (AKIN) or Kidney Disease Improving Global Outcomes (KDIGO) criteria versus other criteria for AKI diagnosis.

RESULTS

A total of 79 RCTs with 10,814 patients were included. While the incidence of postoperative MI did not differ between the RIPC and control groups (8.2% vs 9.7%; risk ratio [RR] = 0.87, 95% confidence interval [CI], 0.76-1.01, P = .07, I2 = 0%), RIPC significantly reduced the incidence of postoperative AKI (22% vs 24.4%; RR = 0.86, 95% CI, 0.77-0.97, P = .01, I2 = 34%). The subgroup analyses showed that RIPC was associated with a reduced incidence of MI in non-high-risk patients, and that RIPC was associated with a reduced incidence of AKI in volatile only anesthesia, in non-high-risk patients, and in the studies using AKIN or KDIGO criteria for AKI diagnosis.

CONCLUSIONS

This meta-analysis demonstrates that RIPC reduces the incidence of AKI after cardiac surgery. This renoprotective effect of RIPC is mainly evident during volatile only anesthesia, in non-high-risk patients, and when AKIN or KDIGO criteria used for AKI diagnosis.

Effect of N-Acetylcysteine on the treatment of acute respiratory distress syndrome in mechanically ventilated patients admitted to the intensive care unit

Background: N-acetylcysteine (NAC) is an antioxidant derived from the amino acid cysteine and is one of the drugs used in the treatment of respiratory diseases. The aim of this study was to investigate the effect of NAC on the treatment of acute respiratory distress syndrome in mechanically ventilated patients admitted to the intensive care unit. Methods: This study was a randomized clinical trial. Patients under mechanical ventilation admitted to the intensive care unit were examined. Patients in the intervention group received daily 150 mg/kg of NAC on the first day of admission and then 50 mg/kg up to the fourth day of admission. Patients in the control group received routine care. The vital signs, level of consciousness, and other important variables were recorded. Data were analyzed using statistical tests and SPSS software version 24. Results: There was no significant difference between MAP, heart rate, respiratory rate, O2Sat, APACHE II score, and pulmonary capacity of the patients in the two groups on the first, second, third and fourth days after the intervention (p>0.05 ). There was no significant difference between the level of consciousness (according to GCS criteria), respiratory index (PAO2/FIO2) and PEEP of patients in the two study groups within 1 to 2 days after the intervention (p>0.05). There was a significant difference between the level of consciousness (based on GCS criteria), respiratory index (PAO2/FIO2) and PEEP of patients in the two study groups within 3 to 4 days after the intervention (p<0.05). There was no significant difference between the duration of hospitalization in the ICU, the time required for mechanical ventilation and the mortality rate of the patients in the two groups (p>0.05). Conclusion: It seems that N-acetylcysteine has a positive effect on the treatment of acute respiratory distress syndrome in mechanically ventilated patients admitted to the intensive care unit.

Investigating the Effect of Near Infra-Red Spectroscopy (NIRS) on Early Diagnosis of Cardiac Surgery-Associated Acute Kidney Injury

Background

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a major adverse effect of cardiac surgery. The early detection of this complication can improve the quality of postoperative care and help prevent this phenomenon.

Methods

In this prospective descriptive-analytical study, 148 patients were enrolled, 107 of whom were selected for analysis between February and September 2019 in the Cardiac Surgery Unit of Golestan Hospital, Ahvaz, Iran. Kidney tissue oxygen saturation was measured at multiple definite times during surgery. Hemoglobin, blood urea nitrogen, creatinine, and lactate were measured during and 48 hours after the surgery.

Results

Forty-one patients were diagnosed with CSA-AKI according to the KDIGO criteria. Parametric and non-parametric analyses showed no significant difference between the CSA-AKI and non-CSA-AKI groups in the demographic parameters. Repeated measures ANOVA showed no significant difference in parameters, except for BUN. Repeated measures ANOVA showed a significant difference between both groups and time factors (P < 0.001, P = 0.0006, respectively). The ROC curve analyses showed that in a single point of time, the difference in the middle of CPB time from baseline had a high value in the prediction of AKI (AUC: 0.764; CI: 0.57 - 0.951).

Conclusions

Kidney saturation monitoring could be considered in cardiac surgery for the rapid detection of CSA-AKI. Although kidney tissue saturation is not correlated directly to the arterial oxygen saturation, the physician and the surgery team can predict the chance of acute kidney injury.

The role of exogenous Fibrinogen in cardiac surgery: stop bleeding or induce cardiovascular disease

The surgical treatment contributes to broad variety of cardiovascular diseases (CVD). Due to many involved factors in preoperative bleeding, it is almost difficult to perform better Haemostatic approach. Fibrinogen is a major blood glycoprotein and a coagulation factor which decreases postoperative bleeding. It has a potential role in platelet activation and bleeding inhibition; it may reflect the inflammatory responses and be related to the endothelial dysfunction. Fibrinogen can act as a pro-inflammatory element via increasing some inflammatory markers including IL-6, tumor necrosis factor-α (TNF-α), monocyte chemo attractant protein (MCP-1), macrophage inflammatory protein-1 (MIP-1a and b), matrix metalloproteinase (MMP-1 and MMP-9) and Toll-like Receptors (TLRs); through activation of these factors, fibrinogen may induce some inflammatory mechanisms such as focal adhesion kinase (FAK), mitogen-activated protein kinases (MAPK) and nuclear factor κB (NF-κB) pathways. It may cause endothelial dysfunction by increasing P and E-selection, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels which activate MAPK and NF-κB pathways. This factor is also associated with increased exocytosed von Willebrand factor (vWF) as well as activation of Rho-GTPase mechanism. All of these data demonstrate the dual role of fibrinogen in cardiac surgeries, bleeding inhibition and CVD. Therefore, identifying the CVD factors is helpful for designing preventive strategies and alternative drugs.

The potential similarities of COVID-19 and autoimmune disease pathogenesis and therapeutic options: new insights approach

Abstract

Cytokine pathways and their signaling disorders can be the cause of onset and pathogenesis of many diseases such as autoimmune diseases and COVID-19 infection. Autoimmune patients may be at higher risk of developing infection due to the impaired immune responses, the use of immunosuppressive drugs, and damage to various organs. Increased secretion of inflammatory cytokines and intolerance of the patient’s immune system to COVID-19 infection are the leading causes of hospitalization of these patients. The content used in this paper has been taken from English language articles (2005–2020) retrieved from the PubMed database and Google Scholar search engine using “COVID-19,” “Autoimmune disease,” “Therapeutic,” “Pathogenesis,” and “Pathway” keywords. The emergence of COVID-19 and its association with autoimmune disorders is a major challenge in the management of these diseases. The results showed that the use of corticosteroids in the treatment of autoimmune diseases can make diagnosis and treatment of COVID-19 more challenging by preventing the fever. Due to the common pathogenesis of COVID-19 and autoimmune diseases, the use of autoimmune drugs as a possible treatment option could help control the virus.

Key Points

• Inflammatory cytokines play an essential role in the pathogenesis of COVID-19

• ACE2 dysfunctions are related to the with COVID-19 and autoimmune diseases

• The use autoimmune diseases drugs can be useful in treating COVID-19

Perioperative Cardioprotection by Remote Ischemic Conditioning

Remote ischemic conditioning has been investigated for cardioprotection to attenuate myocardial ischemia/reperfusion injury. In this review, we provide a comprehensive overview of the current knowledge of the signal transduction pathways of remote ischemic conditioning according to three stages: Remote stimulus from source organ; protective signal transfer through neuronal and humoral factors; and target organ response, including myocardial response and coronary vascular response. The neuronal and humoral factors interact on three levels, including stimulus, systemic, and target levels. Subsequently, we reviewed the clinical studies evaluating the cardioprotective effect of remote ischemic conditioning. While clinical studies of percutaneous coronary intervention showed relatively consistent protective effects, the majority of multicenter studies of cardiac surgery reported neutral results although there have been several promising initial trials. Failure to translate the protective effects of remote ischemic conditioning into cardiac surgery may be due to the multifactorial etiology of myocardial injury, potential confounding factors of patient age, comorbidities including diabetes, concomitant medications, and the coadministered cardioprotective general anesthetic agents. Given the complexity of signal transfer pathways and confounding factors, further studies should evaluate the multitarget strategies with optimal measures of composite outcomes.

Significance of Cardiac Troponin I Elevation in Traumatic Brain Injury Patients

Background

Myocardial dysfunction is frequently described as an underlying cause of mortality in traumatic brain injury (TBI) known as brain-cardiac link. However the impact on prognosis of a disease remains uncertain.

Objectives

The current study aimed at investigating the correlation between TBI and cardiac troponin I (cTnI) rise and in-hospital mortality rate among patients with TBI.

Methods

In the current prospective study TBI patients with abbreviated injury scale score (AIS) > 3 and Glasgow coma scale (GCS) score ≤ 8 with cTnI measurement within the first 24 hours of admission were evaluated. Chi-square, Kruskal-Wallis, Mann-Whitney U and Logistic Regression tests were used for data analysis.

Results

A total of 166 eligible patients were studied .The mean age of the cases was 37.64 ± 17.21 years, largely under 65 (93.4%) and male (86.7%).The most common injuries were cerebral contusion (35.1%), while motor vehicle crash (MVC) was the most common cause of injuries (83.73%); 59 % of the patients showed detectable cTnI concentrations within 24 hours of admission; 65.7% of the patients expired; they showed higher levels of cTnI compared to survivors that showed lower levels, 0.148 ± 0.074 vs 0.057 ± 0.055, respectively (P < 0.001). Moreover, a significant association was observed between mortality rate and lower admission GCS 3.49 ± 1.08 vs 6.79 ± 1.66, respectively (P < 0.001).

Conclusions

Increased cTnI levels could be a predictor of mortality among patients with TBI. Its measurement and investigation for therapeutic strategies could lead to better management of these cases.