Higher perfusion pressure and pump flow during cardiopulmonary bypass are beneficial for kidney function-a single-centre prospective study.

Background: Kidneys play an essential role in the circulatory system, regulating blood pressure and intravascular volume. They are also set on maintaining an adequate filtration pressure in the glomerulus. During the CPB, a decrease in systemic blood pressure and hemoglobin concentration may lead to renal ischemia and subsequent acute kidney injury. Methods: One hundred nine adult patients were prospectively enrolled in this study. The intervention in this study was increasing the flow of the CPB pump to reach the target MAP of > 90 mmHg during the procedure. The control group had a standard pump flow of 2.4 L/min/m2. Results: Standard pump flow of 2.4 L/min/m2 resulted in mean MAP < 90 mmHg during the CPB in most patients in the control group. Maintaining a higher MAP during CPB in this study population did not affect CSA-AKI incidence. However, it increased the intraoperative and postoperative diuresis and decreased renin release associated with CPB. Higher MAP during the CPB did not increase the incidence of cerebrovascular complications after the operation; patients in the highest MAP group had the lowest incidence of postoperative delirium, but the result did not obtain statistical significance. Conclusion: Maintaining MAP > 90 mmHg during the CPB positively impacts intraoperative and postoperative kidney function. It significantly reduces renal hypoperfusion during the procedure compared to MAP < 70 mmHg. MAP > 90 mmHg is safe for the central nervous system, and preliminary results suggest that it may have a beneficial impact on the incidence of postoperative delirium.

Alterations to Kidney Physiology during Cardiopulmonary Bypass-A Narrative Review of the Literature and Practical Remarks.

INTRODUCTION: According to different authors, cardiac surgery-associated acute kidney injury (CSA-AKI) incidence can be as high as 20-50%. This complication increases postoperative morbidity and mortality and impairs long-term kidney function in some patients. This review aims to summarize current knowledge regarding alterations to renal physiology during cardiopulmonary bypass (CPB) and to discuss possible nephroprotective strategies for cardiac surgeries. Relevant sections: Systemic and renal circulation, Vasoactive drugs, Fluid balance and Osmotic regulation and Inflammatory response. CONCLUSIONS: Considering the available scientific evidence, it is concluded that adequate kidney perfusion and fluid balance are the most critical factors determining postoperative kidney function. By adequate perfusion, one should understand perfusion with proper oxygen delivery and sufficient perfusion pressure. Maintaining the fluid balance is imperative for a normal kidney filtration process, which is essential for preserving the intra- and postoperative kidney function. FUTURE DIRECTIONS: The review of the available literature regarding kidney function during cardiac surgery revealed a need for a more holistic approach to this subject.

The Rate of Postoperative Mortality and Renal and Respiratory Complications are Increased in Patients with Extreme Obesity Undergoing Cardiac Surgery - A Retrospective Observational Cohort Study of 8848 Patients.

Introduction: The importance of obesity as a potential risk factor in open heart surgery is well known. The epidemic of extreme obesity is an increasing public health concern and raises alerts regarding postoperative complications and mortality in patients undergoing cardiac surgery. The study aimed to analyze the impact of extreme obesity (BMI≥40) on the frequency of postoperative complications, as well as early and delayed mortality compared to patients with a lower body mass. Materials and Methodology: This retrospective observational cohort study involved patients, over the age of 18, undergoing cardiac surgery with cardiopulmonary bypass at the Cardiac Surgery Department of the Pomeranian Medical University in Szczecin, Poland between January 1st, 2010 and December 31st, 2018. The patients included in the study were allocated into two subgroups depending on the BMI index (Group I BMI≥40 vs Group II BMI<40). Results: A total of 8848 adult patients of both genders were included. Baseline characteristics for Group I and Group II were mean age 64.07±7.76 vs 65.10±9.68 years (p=0.123), mean BMI 42.13±2.44 vs 28.55±4.23 (p<0.001), with more females in Group I (58.04% vs 29.06%) and more males in Group II (70.94% vs 29.06%), p<0.001. The predicted perioperative risk using the EuroScore Logistics scale was higher in a group with BMI≥40 (p<0.001). Regression analysis with adjustment for confounding factors showed a statistically significant relationship between BMI≥40 and postoperative respiratory failure (OR=1.760, p=0.043), acute kidney injury AKIN2 (OR=2.082, p=0.044) and AKIN3 (OR=2.743, p=0.039). 30-day mortality in the univariate analysis showed a statistically significant relationship, however, after modifying the results with interfering factors, no statistical significance was obtained. Conclusion: The risk of postoperative acute respiratory failure and acute renal injury was increased in patients with BMI≥40. The probability of 30-day survival of patients after cardiac surgery was much lower in people with extreme obesity, although it was related to the dominant comorbidities. The 10-year survival was comparable in both groups.

The Utility of Novel Kidney Injury Biomarkers in Early Detection of CSA-AKI.

Cardiac surgery-associated acute kidney injury (CSA-AKI) is one of the most common complications of cardiac surgery procedures. In this study, the authors attempt to provide new data regarding the application of novel kidney injury biomarkers in the early diagnostics of CSA-AKI. 128 adult patients undergoing elective cardiac surgery procedures with the use of cardiopulmonary by-pass (CPB) were enrolled in this study. Novel kidney injury biomarkers were marked in the plasma and urine 6 h after weaning from the CPB. A significant difference in the postoperative biomarkers' concentration between the AKI and no-AKI group was found, regarding plasma IL-8, plasma TNF-α and urine NGAL, normalized for creatinine excretion (NGAL/Cr). These were also independent predictors of CSA-AKI. An independent risk factor for CSA-AKI proved to be preoperative CKD. Plasma IL-8 and TNF-α, as well as urine NGAL/Cr, are independent early indicators of CSA-AKI and pose a promising alternative for creatinine measurements. The cut-off points for these biomarkers proposed in this investigation should be confronted with more data and revised to achieve a suitable diagnostic value.

Percentage of hematocrit decrease after the initiation of cardiopulmonary bypass-clinical implications and affecting factors.

Decrease of patient's hematocrit level is a natural process which occurs during the initiation of cardiopulmonary bypass. To some extent it is a beneficial occurrence, but excessive hematocrit decrease can lead to many complications and increase patient's demand for blood transfusion. In this study authors investigated the causes and clinical implications of ≥30% hematocrit decrease after the initiation of cardiopulmonary bypass. Retrospective analysis of 172 patients undergoing elective cardiac surgery procedures was conducted. It was concluded that 30% or greater hematocrit decrease (comparing to preoperative level) after the initiation of cardiopulmonary bypass, is associated with an increased demand for blood transfusion. The most important factors influencing hematocrit decrease after the initiation of cardiopulmonary bypass proved to be: lower BMI, female gender, more advanced age and the usage of priming fluid of higher volume and lower osmolality.

Assessment of Platelet Reactivity and Inflammatory Markers in Coronary Artery Bypass Graft Patients Treated with Acetylsalicylic Acid with Flavonoid Supplementation.

The recommended pharmacological therapy for patients with coronary artery disease (CAD) treated by coronary artery bypass grafting (CABG) is acetylsalicylic acid (ASA). To improve the antiplatelet effect, supplementation with flavonoids is also recommended. The aim of this study was to estimate anti-aggregation properties of diosmin, in combination with ASA, pre- and postoperatively and assess the relationship of this therapy with inflammatory processes in CAD patients undergoing CABG. The study patients (n = 26) took diosmin (1000 mg/day); the control patients (n = 27) took a placebo. The therapeutic period for taking diosmin was from at least 30 days before to 30 days after CABG. All patients also took 75 mg/day ASA. Platelet aggregation and IL-6, CRP, and fibrinogen concentrations were determined before and 30 days after surgery. Results showed that diosmin did not enhance the anti-aggregation effect of ASA at any assessment time. However, there was a stronger anti-aggregation effect 30 days after surgery that was diosmin independent and was associated with acute-phase markers in the postoperative period. Increased levels of inflammatory markers in the late phase of the postoperative period may provide an unfavorable prognostic factor in long-term follow-up, which should prompt the use of stronger antiplatelet therapy in patients after CABG.

Assessment and Prognosis in CSA-AKI Using Novel Kidney Injury Biomarkers: A Prospective Observational Study.

BACKGROUND: There is a need for early diagnostic solutions for cardiac surgery associated acute kidney injury (CSA-AKI) as serum creatinine changes do not occur dynamically enough. Moreover, new approaches are needed for kidney protective strategy in patients undergoing cardiac surgery procedures; Methods: Samples of serum and urine were taken from the selected group of patients undergoing elective cardiac surgery procedures. The aim of this study was to assess the utility of specific inflammation and kidney injury biomarkers in the early diagnostic of CSA-AKI and in the prognosis of long-term postoperative kidney function; Results: At 6 h after weaning from cardiopulmonary bypass, there were significant differences in IL-6, IL-8, TNF-α, MMP-9 and NGAL concentrations in patients with CSA-AKI, compared to the control group. Serum IL-8 and urine NGAL 6 h after weaning from CPB proved to be independent acute kidney injury predictors. The TNF-α, MMP-9, IL-18, TIMP-1 and MMP-9/TIMP-1 ratio in the early postoperative period correlated with long-term kidney function impairment; Conclusions: Novel kidney injury biomarkers are an eligible tool for early diagnosis of CSA-AKI. They are also reliable indicators of long-term postoperative kidney function impairment risk after cardiac surgery procedures.

Cardiac Complications Following Cardiac Surgery Procedures.

BACKGROUND: Elderly patients and those with multiple concomitant disorders are nowadays qualified for cardiac surgery procedures, which is related to higher incidence of the postoperative complications. AIM: The aim of this study was a retrospective analysis of the perioperative factors potentially contributing to occurrence of cardiac incidents after cardiac surgery procedures. METHODS: Data of 552 patients of the cardiac surgery clinic were collected and analyzed. Data concerning medical history, previous treatment, laboratory results, additional tests results, operation and hospitalization period were examined. RESULTS: In the study population of 552 patients, cardiac complications were observed in 49.5% of them. Among cardiac complications, the most frequent were supraventricular tachycardia (30.1%) and atrial fibrillation (27.4%). Postoperative bradycardia occurred in 5.25% patients, half of whom required temporary cardiac pacing. CONCLUSIONS: The risk of incidence of cardiac complications after cardiac surgery procedures depends mostly on patient's age, EuroSCORE Logistic (ESL) score, left ventricular ejection fraction, myocardial hypertrophy, presence of paroxysmal AF and coincidence of nephrological complications. The necessity of performing more than one heart defibrillation after removing aortic cross-clamp favors early postoperative bradycardia. Considering the outcomes of this study, continuing reperfusion at least until 1/3 of the aortic cross-clamp time brings no additional benefits to the patients.

Analysis of the influence of respiratory disorders observed in preoperative spirometry on the dynamics of early inflammatory response in patients undergoing isolated coronary artery bypass grafting.

BACKGROUND: Preoperative spirometry provides measurable information about the occurrence of respiratory disorders. The aim of this study was to assess the association between preoperative spirometry abnormalities and the intensification of early inflammatory responses in patients following coronary artery bypass graft in extracorporeal circulation. MATERIAL AND METHODS: The study involved 810 patients (625 men and 185 women) aged 65.4±7.9 years who were awaiting isolated coronary artery bypass surgery. On the basis of spirometry performed on the day of admittance to the hospital, the patients were divided into three groups. Patients without respiratory problems constituted 78.8% of the entire group. Restricted breathing was revealed by spirometry in 14.9% and obstructive breathing in 6.3% of patients. RESULTS: Inter-group analysis showed statistically significant differences in C-reactive protein (CRP) between patients with restrictive spirometry abnormalities and patients without any pulmonary dysfunction. CRP concentrations differed before surgery (P=0.006) and on the second (P<0.001), fourth (P=0.005) and sixth days after surgery (P=0.029). There was a negative correlation between CRP levels and FEV1. CONCLUSION: In our study, the most common pulmonary disorders in the coronary artery bypass graft patients were restrictive. Patients with abnormal spirometry results from restrictive respiratory disorders have an elevated level of generalized inflammatory response both before and after the isolated coronary artery bypass surgery. Therefore, this group of patients should be given special postoperative monitoring and, in particular, intensive respiratory rehabilitation immediately after reconstitution.

Postponed surgery of an acute aortic dissection (type A) in a Jehovah's Witness with significant hemostatic disorders.

In this case report, we present the treatment of an acute type A aortic dissection in a Jehovah's Witness patient. In accordance with the will of the patient, blood products were not used. Additionally, the patient had significant hemostatic disorders due to the use of antiplatelet drugs.

The Use of Vacuum-Assisted Closure in Purulent Complications and Difficult-To-Heal Wounds in Cardiac Surgery.

BACKGROUND: Sternal wound infections are a serious and potentially fatal complication of cardiac surgery. OBJECTIVES: The aim of the study was to analyze the results of using the vacuum-assisted closure (VAC) system over a 4-year period. MATERIAL AND METHODS: Quantitative VAC performance data from a retrospective review of a consecutive cohort of 47 patients treated with VAC for post-cardiac surgery wound complications were collected and statistically analyzed. In the study group 35 patients developed infections of the post-operative chest wound. In 12 other patients wound dehiscence was observed, but repeated cultures did not reveal the presence of any bacteria. RESULTS: The statistical analysis identified the following as significant risk factors: age, female sex, being overweight, a high total logistic EuroScore, the use of both internal thoracic arteries for bypass grafting, and diabetes. In the wound negative culture group the total length of hospital stay was significantly shorter than in the wound positive culture group. Mortality in this group was 0.0% vs. 5.7% in the wound positive culture group. In the study material, Gram-negative bacteria were responsible for 77% of the post-operative wound infections, with only 14% Gram-positive wound cultures. No complications were related to VAC use. CONCLUSIONS: The use of negative-pressure wound therapy with other concomitant surgical procedures is a good method of treating infected wounds as well as non-contaminated dehiscence of the wound and sternum. Considering that most of the infections within the authors' department are caused by Gram-negative bacteria, it would be beneficial to consider modifying the model of preventive antibiotic treatment to cover the Gram-negative spectrum in addition to the Gram-positive bacteria currently targeted.

Glycated hemoglobin HbA1c - a new risk marker for the outcome of cardiac surgery?

INTRODUCTION: About 30% of patients undergoing cardiac surgery are diabetic, and glycated hemoglobin (HbA1c) is a reliable marker for long-term glucose control. The aim of our study was to examine whether tight glucose control before a cardiac operation results in a better outcome of the surgical treatment. MATERIAL AND METHODS: We performed a retrospective record review of 350 diabetic patients undergoing cardiac surgery in our institution. Preoperative glycemia control was assessed by measurement of the glycated hemoglobin level. The patient population was divided into three groups: group I - patients with HbA1c below 7% (n = 195); group II - patients with HbA1c between 7% and 8% (n = 88); and group III - patients with HbA1c above 8% (n = 67). RESULTS: The demographic data and operating risk in all groups of patients were similar. There were 2 deaths (1.02%) in group I, 2 deaths (2.27%, p = 0.78) in group II and 3 deaths (4.47%, p = 0.20) in group III. Cardiac accidents occurred in 9 patients (4.60%) from group I, 7 patients (7.95%, p = 0.20) from group II, and in 6 patients (9.05%, p = 0.40) from group III. Cerebrovascular accidents (CVA) occurred in 7 (3.58%), 5 (5.68%, p = 0.67) and 5 (7.46%, p = 0.61) patients, respectively. Acute renal dysfunction requiring renal replacement therapy occurred in 4 patients from group I (2.05%), 3 patients from group II (3.40%, p = 0.78) and 4 patients from group III (5.97%, p = 0.23). CONCLUSIONS: A large percentage of diabetic patients referred for cardiac operations have poorly controlled glycemia. Optimal preoperative glycemia control results in lower postoperative mortality and morbidity. In addition, the preoperative HbA1c level is a good indicator of the risk of postoperative complications in diabetic patients undergoing cardiac operations.

Thoracic aorta aneurysm successfully operated on during pregnancy.

We present the case of an asymptomatic 26-year-old female patient with a huge thoracic aneurysm discovered at a routine echo screening. The patient had previously been operated on for coarctation of the aorta in childhood and also had diagnosed bicuspid aortic valve. The operation was carried out in extracorporeal circulation at the 22(nd) week of gestation without any complications. A few months later in the 38(th) week of pregnancy a baby girl was delivered by cesarean section with an Apgar score of 10. The patient is scheduled for implantation of a stent graft to the descending aorta, because the CT of the chest done a few months after delivery confirmed presence of a significant aneurysm located just below the left subclavian artery.