The value of prophylactic antibiotics in coronary artery bypass graft surgery: A review of literature.

Infections have a significant impact on increasing both the morbidity and mortality rate of patients who have undergone coronary artery bypass graft (CABG) surgery. Infection after CABG imposes a clinical and economic burden on patients and health care organizations; therefore, prevention should be on the agenda. This review will focus on the value of using prophylactic antibiotics in coronary artery bypass graft surgery (CABG). Prophylactic antibiotics like cephalosporin and vancomycin are more commonly used antibiotics and are strongly associated with reduced infection risk in patients. The results showed that using antibiotics during the perioperative period and after CABG is an effective strategy for reducing post-infection problems without compromising the patients' clinical outcomes. Diabetic patients are prone to postoperative infection after CABG, however, prophylactic antibiotics should not be the only strategy used to reduce the risk of postoperative infection in diabetic patients. Perioperative glycaemic control is essential for diabetic patients undergoing CABG. Appropriate antibiotic prophylaxis has a great impact on preventing infection after CABG but duration and selecting appropriate antibiotic is important. Standardizing the use of antibiotic prophylaxis reduces the rate of infection and unwanted bacterial resistance, which could subsequently reduce economic costs to patients and public health.

Significance of ST-Segment elevation in V4R lead in patients with anterior myocardial infarction.

BACKGROUND: There is some evidence of the association between ST-segment elevation in the V4R chest lead and the likelihood of anterior wall myocardial infarction; however, the link of this phenomenon with the location and the severity of the coronary involvements in such patients remains uncertain. We aimed to investigate the ST-segment elevation in V4R leads in patients with anterior myocardial infarction and also its effect on prognosis as well as the detection and prediction of the location of arterial stenosis in coronary angiography. METHODS: Data collection was performed by reviewing the hospital recorded files of 195 patients' suspicion of acute myocardial infarction who have been referred within 2 h of the onset of cardiac symptoms. The patients were then categorized into two groups with and without ST elevation in the V4R chest lead. RESULTS: Comparing two groups showed a significantly higher rate of concurrent ST-segment elevation in V1 lead in those with ST-segment elevation in V4R. Echocardiography on the day after anterior myocardial infarction showed LVEF <40% in 74% and 35.2% of patients with and without ST-segment elevation in V4R, respectively, indicating a significant difference. The lesions on proximal LAD were more common in the group with ST-segment elevation in V4R. CONCLUSION: Our study emphasized a high likelihood of ST-segment elevation in V4R lead concurrently with ST-elevation in V1 lead. Also, the appearance of ST-segment elevation in V4R lead can be accompanied with a lower LVEF, myocardial infarct size, involvement of proximal part of LAD, and Wrap around LAD.

Optimal Time Repair of Ventricular Septal Rupture Post Myocardial Infarction.

Ventricular septal rupture (VSR) is an uncommon complication of myocardial infarction (MI). The mortality rate of VSR is high. The management of VSR is including the stabilization of the hemodynamic status and surgical closure of the rupture. In spite of the agreement of experts on the necessity of surgical repair, the timing of VSR repair management remains unclear. In this review article, we evaluate the optimal time repair of VSR. To collect the data, Pubmed, EMBASE, and Cochrane Central Registry databases were searched for potentially suitable studies. Search terms were including "Ventricular Septal Rupture", "Myocardial Infarction", "Timing", and "MI". According to the result of the studies, it seems that the time between VSR detection and its repair is a determining factor in the survival or mortality of patients in post-myocardial infraction VSR. Studies showed that earlier surgical repair in VSR increases the risk of mortality, because in the early phase after MI, infarcted myocardium is very fragile, and it is very difficult surgical repair and increases the risk of recurrent septal defects. The longer time is needed for the heart and different body systems to adapt to the hemodynamic results of the abrupt left to right shunt. It seems that the best time for the operation is after the maturation of VSR with scarring at the edges of the defect. Moreover, in a large number of patients, it is not possible to delay the operation since they are at risk of severe heart failure and organ dysfunction. In these cases operation immediately after diagnosis of VSR is recommended to prevent further hemodynamic deterioration. In hemodynamically compromised patients, it may be considered to use a ventricular assist device, requiring an intra-aortic balloon pump (IABP), or extracorporeal membrane oxygenation (ECMO) preoperative to postpone the operation which leads to higher survival in post-MI-VSD.

The Effect of Melatonin on the Serum Level of Interleukin 6 and Interleukin 9 in Coronary Artery Bypass Grafting Surgery.

OBJECTIVE: Cardiopulmonary bypass has been recognized as one of the main causes of systemic inflammatory response syndrome, leading to post-operative complications. The aim of this study was to investigate the effect of melatonin on the serum levels of interleukin 6 (IL-6) and IL-9 in patients undergoing coronary artery bypass grafting surgery. METHODS: Forty-four patients undergoing elective coronary artery bypass surgery were randomly allocated into two study groups of melatonin (n = 23) and placebo (n = 21). Patients in the melatonin group received two melatonin tablet, 5 mg daily for 3 days before surgery, 10 mg tablet (two doses of 5 mg) 1 h before induction of anesthesia and finally, 10 mg melatonin tablet in the intensive care unit, placebo group patients received placebo at the same time periods. Serum levels of IL-9 and IL-6 were measured as baseline (T1), before induction of anesthesia (T2), 6 and 24 h after off pump (T3, T4). Data were analyzed using SPSS 23 software (IBM Corp., Armonk, NY, USA). RESULTS: The mean serum level of IL-6 was significantly lower in the melatonin group at T3 and T4 (p ＜ 0.05). Also, in both groups, serum levels of IL-6 in T3 showed a significant increase compared to T1. Serum levels of IL-9 had no significant difference between the two groups at T1, T2, T3, and T4. CONCLUSION: The results of this study showed that pre-operative melatonin administration could modify inflammatory cytokines secretion such as IL-6 while it has no significant effect on the serum levels of IL- 9. Neither of the changes was clinically significant.

Prevention of Pulmonary and Venous Thromboembolism Post Coronary Artery Bypass Graft Surgery - Literature Review.

OBJECTIVE: The current review evaluates recent literature on the different aspects of prophylaxis in postoperative pulmonary and venous thromboembolism and their main risk factors. METHODS: The literature survey was carried out based on the PubMed data using the keywords "coronary artery bypass graft" and "venous thromboembolism" as components of the search field title. RESULTS: Studies reported several risk factors for postoperative thromboembolism including advanced age, postoperative immobilization, type of thromboprophylaxis, obesity, and location of the surgery. CONCLUSION: According to the studies, tailored prophylaxis could be easily adapted to decrease the intensity and duration of postoperative thromboembolism in a patient with several disorders and comorbidities, especially in cardiovascular disease.

Prevention of pulmonary and venous thromboembolism post coronary artery bypass graft surgery - literature review

Abstract Objective: The current review evaluates recent literature on the different aspects of prophylaxis in postoperative pulmonary and venous thromboembolism and their main risk factors. Methods: The literature survey was carried out based on the PubMed data using the keywords "coronary artery bypass graft" and "venous thromboembolism" as components of the search field title. Results: Studies reported several risk factors for postoperative thromboembolism including advanced age, postoperative immobilization, type of thromboprophylaxis, obesity, and location of the surgery. Conclusion: According to the studies, tailored prophylaxis could be easily adapted to decrease the intensity and duration of postoperative thromboembolism in a patient with several disorders and comorbidities, especially in cardiovascular disease.

Inferior Vena Cava Repair Using Diaphragm in Animal Model.

BACKGROUND: Repair and reconstruction of the vena cava with an autologous vein requires multiple incisions. Prosthetic material is linked with an increased risk of infection and thrombosis. Therefore in this study, we created an animal model of vena cava repair using the diaphragm. The objective of this study is to assess the feasibility and outcomes of using diaphragm for the repair and replacement of the inferior vena cava (IVC) after resection of a part of the infrarenal IVC in an animal model, as it may be encountered in trauma patients and extensive tumors of retroperitoneum. METHODS: Five healthy dogs of both sexes were prepared. After general anesthesia and laparotomy, a 1 cm width with 4 cm length defect was arranged on anterior aspect of the infrarenal IVC, subsequently, the anterior aspect of the right diaphragm with 1 cm width and 4 cm length was resected and was anastomosed to cover the defect of the IVC as a patch graft, with the pleural side of the diaphragm facing the luminal aspect and the peritoneal side on the outside. The observation period was 6 weeks. RESULTS: All of the IVCs were macroscopically patent without thrombosis and stenosis. Pathologic assay revealed complete endothelialization of diaphragm. One dog died at the third night of operation without distinct reason. CONCLUSIONS: The diaphragm is an accessible and safe option in the repair and reconstruction of IVC particularly when restrictions exist for the use of prosthetic material in a contaminated space of the abdomen.

Atrial Fibrillation Post Coronary Artery Graft Surgery: A Review Of Literature.

Atrial fibrillation (AF) is a failure that is observed in heart disease and is also known to be the most common heart rhythm disturbance post coronary artery bypass surgery. Although AF is considered a transient problem, it is usually accompanied with a variety of complications and morbidity for patients and may result in death. In the present study, pre- and post-operative considerable factors which may increase the risk and mortality of AF, and possible treatments have been concisely reviewed.

A comparative review of the outcomes of using arterial versus venous conduits in coronary artery bypass graft (CABG).

Nowadays one of the most frequent reasons of death in the world is coronary artery disease. CABG is a portion of a common revascularization mediation that is done to supervise CAD by applying vessels that are grafted to revascularize vessels distal from the blockage. Different sources of grafts are included veins (specifically saphenous) and arteries (include mammary and radial arteries). Multiple conduits are used to this end, but the most suitable is left internal mammary artery (LIMA) to the left anterior descending artery (LAD) as a golden standard. Saphenous vein grafts were the guiding approach applied by the vast majority of cardiac surgeons in the 1970s, even though all approaches were supported by doctors. Although the radial artery graft was introduced simultaneously, this approach due to its complications was not as prevalent. This article is aimed to define the pros and cons of applying each kind of grafts according to the results furnished by existent studies. It has also examined the benefits provided by total arterial coronary artery bypass graft against CABG including venous graft for patients with CAD from the perspective of surgeons.

Analgesia and sedation post-coronary artery bypass graft surgery: a review of the literature.

This review aimed to study the role of analgesia and sedation after coronary artery bypass graft (CABG) surgery, regarding pain management, assisted respiration, overall postoperative health care, and hospitalization. Data were collected from Pubmed, Scopus, and Cochrane databases. The following terms were used for the search: "analgesia", "sedation", "coronary artery bypass grafting", CABG", and "opioids". Articles between the years 1988 and 2018 were evaluated. Several opioid and non-opioid analgesics used to relieve surgical pain are regarded as critical risk factors for developing pulmonary and cardiovascular complications in all kinds of thoracic surgery, especially CABG procedures. Effective pain management in post-CABG patients is largely dependent on effective pain assessment, type of sedatives and analgesics administered, and evaluation of their effects on pain relief. A significant challenge is to determine adequate amounts of administered analgesics and sedatives for postoperative CABG patients, because patients often order more sedatives and analgesics than needed. The pain management process is deemed successful when patients feel comfortable after surgery, with no negative side effects. However, postoperative pain management patterns have not included many modern methods such as patient-controlled analgesia, and postoperative pain management drugs are still limited to a restricted range of opioid and non-opioid analgesics.

Intra-aortic balloon pump postcardiac surgery: A literature review.

Intra-aortic balloon pump (IABP) has been the most commonly used mechanical assist circulatory device in many postcardiotomy low output disorders for decades. Mechanism of IABP is based on its inflation in time of the diastolic pressure in the aortic root resulting increase in the blood and oxygen amount of the coronary artery and its deflation in left ventricular afterload during the systolic period. Prophylactic and postoperative application of IABP has been suggested by researchers, which has been commonly used in high-risk patients undertaking coronary artery bypass grafting surgery or percutaneous coronary intervention. Other researchers put forward the idea of the percutaneous IABP insertion throughout the left axillary artery as a reliable and relatively well-tolerated approach and also as a recovery tool to bridge patients with end-stage heart failure to heart transplantation. The current review was aimed to give further insight into routine IABP application by presenting the basic principles and trends in the incidence, management, role of IABP recovery, and long-lasting mortality outcomes in patients with cardiovascular disorders and discussing previous and current evidence.

Comparison of the Efficacy of Oral versus Intravascular Magnesium in the Prevention of Hypomagnesemia and Arrhythmia after CABG.

OBJECTIVE: Cardiac arrhythmias are a common challenge following open-heart surgeries. Hypomagnesemia is believed to be correlated with this condition. Prophylactic intravenous magnesium supplementation has been practiced for a long time in patients undergoing CABG. This study was designed in an attempt to compare the efficacy of oral versus intravenous routes in the prevention of hypomagnesemia and arrhythmia. METHODS: In this interventional clinical study, 82 patients were randomly assigned to 2 groups. All patients were evaluated for baseline serum magnesium level and arrhythmias. One group received 1,600 mg of oral magnesium hydroxide through nasogastric (NG) tube prior to surgery, while the other group received 2 g of magnesium sulfate during the induction of anesthesia. The serum magnesium level was monitored for 48 hours after the operation. The difference in preoperative hypomagnesemia was non-significant (Sig: 0.576). RESULTS: During the operation, the serum magnesium level peaked around 4 mg/dL, and no hypomagnesemia was detected in any patient. Although the curve of oral group declined parallel and below that of intravenous (IV) group, no significant differences were detected during postoperative monitoring. In addition, a prevalence of arrhythmia of 13.9% and 6.5% was noticed in IV and oral groups, respectively (OR: 0.428). CONCLUSION: Providing 1,600 mg of oral magnesium supplement to patients is as effective as 2,000 mg of magnesium sulfate IV in preventing hypomagnesemia and arrhythmia after CABG. Thus, the authors introduce this treatment regimen as a promising and cost-effective method.

Comparison of the efficacy of oral versus intravascular magnesium in the prevention of hypomagnesemia and arrhythmia after cabg

Abstract Objective: Cardiac arrhythmias are a common challenge following open-heart surgeries. Hypomagnesemia is believed to be correlated with this condition. Prophylactic intravenous magnesium supplementation has been practiced for a long time in patients undergoing CABG. This study was designed in an attempt to compare the efficacy of oral versus intravenous routes in the prevention of hypomagnesemia and arrhythmia. Methods: In this interventional clinical study, 82 patients were randomly assigned to 2 groups. All patients were evaluated for baseline serum magnesium level and arrhythmias. One group received 1,600 mg of oral magnesium hydroxide through nasogastric (NG) tube prior to surgery, while the other group received 2 g of magnesium sulfate during the induction of anesthesia. The serum magnesium level was monitored for 48 hours after the operation. The difference in preoperative hypomagnesemia was non-significant (Sig: 0.576). Results: During the operation, the serum magnesium level peaked around 4 mg/dL, and no hypomagnesemia was detected in any patient. Although the curve of oral group declined parallel and below that of intravenous (IV) group, no significant differences were detected during postoperative monitoring. In addition, a prevalence of arrhythmia of 13.9% and 6.5% was noticed in IV and oral groups, respectively (OR: 0.428). Conclusion: Providing 1,600 mg of oral magnesium supplement to patients is as effective as 2,000 mg of magnesium sulfate IV in preventing hypomagnesemia and arrhythmia after CABG. Thus, the authors introduce this treatment regimen as a promising and cost-effective method.

Investigation of associated factors with post-operative outcomes in patients undergoing Tetralogy of Fallot correction.

BACKGROUND: Tetralogy of Fallot (TOF) is one of the congenital cardiac abnormality which occurs during embryonic time. Although surgical correction, especially early operation, is the best way to treat patients, still contributing factors in morbidity and mortality is controversial. The objective of this study is to investigate potential factors which might be correlated with post-operative outcomes of TOF. METHODS: In this retrospective study, 349 monitored patients with TOF correction were selected. Median of age was 4 (0.66-8) year, 58% of patients were male and 42% were female. Time of inotropic drug, extubation time, and ICU stay were considered as post-operative outcomes which extension of each of them increased the risk of death. RESULTS: Ventricular septal defect enlargement was associated with longer extubation time and ICU stay. Higher ratio of pre-operative haematocrit was correlated with mortality (0.047). CONCLUSIONS: Results of this study demonstrated that haematocrit ratio before operation should be considered as a predictive factor, and patients with higher ratio of haematocrit require more care after operation. VSD enlargement is associated with longer extubation time and ICU stay.

Metabolic effects of tourniquet application in burn patients.

BACKGROUND: Despite several studies investigating the pathophysiologic effects of tourniquet usage in extremity surgeries, there are not enough data about these effects in adhesion release surgeries of burn patients. In the light of numerous metabolic changes of burn tissues, we tried to determine whether there are any significant differences in metabolic responses of burn tissues to tourniquet ischemia in comparison to the findings of other studies in non burn tissue responses during tourniquet usage in extremity surgeries. METHODS: From March 2009 to April 2011, eighteen patients who were candidates for performing upper extremity adhesion release surgeries were enrolled. Patients with renal, hepatic, metabolic and any other underlying diseases were excluded from the study. Blood samples for determination of pH, pCO2 and HCO3 were obtained from the occluded hand (as the local response indicator of the body to ischemia) and the other hand too (as the systemic response indicator). The time for blood sampling was just before tourniquet inflation, 30 seconds, one minute, three minutes and five minutes after cuff inflation. RESULTS: Thirty seconds after tourniquet release, a rapid decrease was noticed in pH values (7.38±0.04-->7.21±0.08). This decrease was seen after 60s in the opposite hand (7.38±0.04-->7.27±0.01) and returned to the baseline values after 5 minutes in both hands. The blood PCO2 value in the occluded hand was found to be increased 30s after tourniquet release (34.93±3.96-->50.06±11.78), while this increase was seen after 180s in the opposite hand too (34.93±3.96-->38.98±9.21). HCO3 value increased after 30s (19.79±2.31-->20.62±2.37) in the occluded hand, but this increase was visible after 60s in the opposite hand. We found no significant difference in the response of burn patients to tourniquet ischemia in comparison to non-burn patients. CONCLUSION: There was no extra risk in the application of tourniquet in extremity surgeries of burn patients in comparison to non-burn patients. So current protocols of tourniquet application in non-burn patients can be used for adhesion release surgeries in burn patients without any extra caution.