The Neurocognitive Outcomes of Hemodilution in Adult Patients Undergoing Coronary Artery Bypass Grafting Using Cardiopulmonary Bypass

Objective:The study aimed to evaluate the effect of mild and moderate hemodilution during CPB on the neurocognitive dysfunction in patients undergoing coronary artery bypass grafting. Design: A randomized clinical study. Setting: Cardiac center. Patients: 186 patients scheduled for cardiac surgery with cardiopulmonary bypass. Intervention: The patients were classified into 2 groups (each = 93), Mild hemodilution group: The hematocrit value was maintained >25% by transfusion of packed?red blood cells plus hemofiltration during CPB. Moderate hemodilution group: the hematocrit value was maintained within the range of 21?25%. Measurements: The monitors included the hemofiltrated volume, number of transfused packed red blood cells, and the incidence of postoperative cognitive dysfunction. Main Results: The hemofiltrated volume during CPB was too much higher with mild hemodilution compared to the moderate hemodilution (p = 0.001). The number of the transfused packed red blood cells during CPB was higher with mild hemodilution compared to the moderate hemodilution (p = 0.001), but after CPB, the number of the transfused packed red blood cells was lower with the mild hemodilution group than the moderate hemodilution (p = 0.001). The incidence of total postoperative neurological complications was significantly lower with the mild hemodilution group than moderate hemodilution (p = 0.033). The incidence of neurocognitive dysfunction was significantly lower with mild hemodilution group than moderate hemodilution (p = 0.042). Conclusions: The mild hemodilution was associated with a significant decrease in the incidence of neurocognitive dysfunction compared to moderate hemodilution in patients undergoing coronary artery bypass grafting. Also, the transfused packed red blood cells increased during CPB and decreased after CPB with the mild hemodilution than moderate hemodilution.

The perioperative effect of magnesium sulfate in patients with concentric left ventricular hypertrophy undergoing cardiac surgery: A double-blinded randomized study

Objective: The objective of this study was to assess the cardioprotective effect of magnesium sulfate in patients with left ventricular concentric hypertrophy undergoing cardiac surgery. Design: The study was a double-blinded randomized study. Setting: This study was conducted at a cardiac center. Patients: The study included 250 patients. Intervention: The study included two groups (each = 125): Group M – the patients who received magnesium sulfate infusion (15 mg/kg/h). The infusion was started 20 min before induction, during surgery, and the first postoperative 24 h. Group C – the patients who received an equal amount of normal saline. Measurements: The variables included troponin I level, creatinine kinase-MB (CK-MB) level, electrocardiograph (ECG) with automatic ST-segment analysis (leads II and V), E/A peak ratio, end-diastolic volume, cardiac index (CI), heart rate, mean arterial blood pressure (MAP), mean arterial pulmonary pressure (mPAP), pulmonary and systemic vascular resistances, and pharmacological and mechanical support. Main Results: The troponin I level, CK-MB, and ECG changes were lower in Group M than Group C (P < 0.05). The E/A peak ratio and end-diastolic volume increased in Group M than Group C (P < 0.05). There was a significant increase in the CI and a decrease in the heart rate, mPAP, pulmonary vascular resistances, and pharmacological and mechanical support in Group M compared to Group C (P < 0.05). There were minimal changes in the MAP and systemic vascular resistance in Group M compared to Group C (P < 0.05). Conclusion: The magnesium sulfate provides a cardioprotective effect in patients with concentric ventricular hypertrophy undergoing cardiac surgery. It decreases the incidence of perioperative myocardial infarction and arrhythmia. Furthermore, it decreases the requirement of pharmacological and mechanical support.

The effect of perioperative magnesium sulfate on blood sugar in patients with diabetes mellitus undergoing cardiac surgery: A double-blinded randomized study

Objective: The aim of the present study was to evaluate the perioperative effect of magnesium infusion on blood sugar level in patients with diabetes mellitus undergoing cardiac surgery. Design: This was a double-blind randomized study. Setting: The study was conducted at cardiac center. Patients: The study included 122 adult patients. Intervention: Group M – The patients received a continuous infusion of magnesium sulfate (without a loading dose) at 15 mg/kg/h. The infusion rate was started 20 min before induction maintained during surgery and the first postoperative 24 h. The medication was prepared by adding 5 g magnesium sulfate in 50 ml syringe. Group C – The patients received equal amount of normal saline. Measurements: The monitors included heart rate, mean arterial blood pressure, central venous pressure, urine output, blood levels of magnesium, sugar, and potassium. Results: The blood sugar level and the required insulin significantly decreased with Group M than Group C (P < 0.05). There were minimal changes in the potassium level in Group M, but potassium decreased in patients of Group C (P < 0.05). The amount of urine output was too much higher in Group M than Group C (P < 0.05). The pharmacological and mechanical support significantly decreased with Group M than Group C (P < 0.05). The hospital and Intensive Care Unit length of stay significantly decreased with Group M than Group C (P < 0.05). Conclusion: The magnesium sulfate produced a better-controlled effect on the blood sugar level. It decreased the requirement of insulin infusion and minimized the changes in the blood level of potassium.

Effect of magnesium sulphate and milrinone on cerebral vasospasm after aneurysmal subarachnoid hemorrhage: a randomized study / Efeitos do sulfato de magnésio e da milrinona sobre o vasoespasmo cerebral após hemorragia subaracnoidea por aneurisma: estudo randômico

Abstract Background: Aneurysmal subarachnoid hemorrhage is an important cause of premature death and disability worldwide. Magnesium sulphate is shown to have a neuroprotective effect and it reverses cerebral vasospasm. Milrinone is also used in the treatment of cerebral vasospasm. The aim of the present study was to compare the effect of prophylactic magnesium sulphate and milrinone on the incidence of cerebral vasospasm after subarachnoid hemorrhage. Methods: The study included 90 patients with aneurysmal subarachnoid hemorrhage classified randomly (by simple randomization) into two groups: magnesium sulphate was given as an infusion of 500 mg.day-1 without loading dose for 21 days. Group B: milrinone was given as an infusion of 0.5 µg.kg-1.min-1 without loading dose for 21 days. The cerebral vasospasm was diagnosed by mean cerebral blood flow velocity in the involved cerebral artery (mean flow velocity ≥ 120 cm.s-1), neurological deterioration by Glasgow coma scale, or angiography (the decrease in diameter of the involved cerebral artery >25%). Results: The mean cerebral blood flow velocity decreased significantly in the magnesium group compared to milrinone group through Day 7, Day 14 and Day 21 (p < 0.001). The incidence of cerebral vasospasm decreased significantly with magnesium compared to milrinone (p = 0.007). The Glasgow coma scale significantly improved in the magnesium group compared to milrinone group through Day 7, Day 14 and Day 21 (p = 0.036, p = 0.012, p = 0.016, respectively). The incidence of hypotension was higher with milrinone than magnesium (p = 0.012). Conclusions: The incidence of cerebral vasospasm after aneurysmal subarachnoid hemorrhage was significantly lower and Glasgow coma scale significantly better with magnesium when compared to milrinone. Milrinone was associated with a higher incidence of hypotension and requirement for dopamine and norepinephrine when compared to magnesium.

Resumo Justificativa: A hemorragia subaracnoidea por aneurisma é uma importante causa de morte prematura e de incapacidade em todo o mundo. O sulfato de magnésio mostra um efeito neuroprotetor e reverte o vasoespasmo cerebral. A milrinona também é usada no tratamento de vasoespasmo cerebral. O objetivo do presente estudo foi comparar o efeito profilático do sulfato de magnésio e da milrinona sobre a incidência de vasoespasmo cerebral após hemorragia subaracnoidea. Métodos: O estudo incluiu 90 pacientes com hemorragia subaracnoidea por aneurisma randomicamente distribuídos (randomização simples) em dois grupos: sulfato de magnésio foi administrado em infusão de 500 mg.dia-1 sem dose de ataque durante 21 dias. O Grupo B recebeu milrinona em infusão de 0,5 µg.kg-1·min-1 sem dose de ataque durante 21 dias. O vasoespasmo cerebral foi diagnosticado pela velocidade média do fluxo sanguíneo cerebral na artéria cerebral envolvida (velocidade média do fluxo ≥ 120 cm.s-1), a deterioração neurológica por escala de coma de Glasgow ou angiografia (diminuição do diâmetro da artéria cerebral envolvida > 25%). Resultados: A velocidade média do fluxo sanguíneo cerebral diminuiu significativamente no grupo magnésio em comparação com o grupo milrinona nos dias 7, 14 e 21 (p < 0,001). A incidência de vasoespasmo cerebral diminuiu significativamente com o magnésio em comparação com milrinona (p = 0,007). A escala de coma de Glasgow melhorou significativamente no grupo magnésio em comparação com o grupo milrinona nos dias 7, 14 e 21 (p = 0,036, p = 0,012, p = 0,016, respectivamente). A incidência de hipotensão foi maior com milrinona do que com magnésio (p = 0,012). Conclusões: A incidência de vasoespasmo cerebral após hemorragia subaracnoidea por aneurisma foi significativamente menor e a escala de coma de Glasgow significativamente melhor com magnésio em comparação com milrinona. A milrinona foi associada a uma maior incidência de hipotensão e necessidade de dopamina e norepinefrina em comparação com o magnésio.

Assessment of the effect of two regimens of milrinone infusion in pediatric patients undergoing fontan procedure: A randomized study

Objective: The aim of the study was to compare the effect of two different regimens of milrinone on hemodynamics and oxygen saturation in pediatric patients undergoing Fontan procedure. Design: This was a randomized study. Setting: Cardiac centers. Patients: This study included 116 patients undergoing Fontan procedure. Material and Methods: Group E: Milrinone was started as infusion 0.5 μg/kg/min without a loading dose at the beginning of cardiopulmonary bypass (CPB) followed by infusion 0.5–0.75 μg/kg/min in the pediatric cardiac surgical intensive care unit (PSICU). Group L: Milrinone was started as a loading dose 50 μg/kg over 10 min before weaning from CPB followed by infusion 0.5–0.75 μg/kg/min in the PSICU. Measurements: Heart rate, mean arterial blood pressure, central venous pressure, transpulmonary pressure, cardiac index, pharmacological support, lactate level, urine output, oxygen saturation, ICU, and hospital length of stay. Main Results: There were no changes in the heart rate and mean arterial blood pressure (P > 0.05). The increase in the postoperative central venous pressure, transpulmonary pressure and lactate level was lower in Group E than Group L (P < 0.05). The increase in the postoperative cardiac index, oxygen saturation, and urine output was higher in Group E than Group L (P < 0.05). The requirement for pharmacological support was lower in the Group E (P < 0.05). The ICU and hospital length of stay were shorter in the Group E than Group L (P < 0.05). Conclusion: Early use of milrinone during Fontan procedure facilitated the weaning from CPB, decreased the elevation in the central venous pressure, transpulmonary gradient pressure, and the requirement for pharmacological support. Furthermore, it increased the cardiac index and arterial oxygen saturation.

Assessment the effect of dexmedetomidine on incidence of paradoxical hypertension after surgical repair of aortic coarctation in pediatric patients

Objective: The aim of the study was to assess the effect of dexmedetomidine on the incidence of paradoxical hypertension in patients undergoing aortic coarctation repair. Design: Randomized observational study. Setting: University hospital and cardiac center. Patients: The study included 108 pediatric patients with isolated aortic coarctation. Methods: The patients were classified into two groups (each = 54): Group D: the patients received dexmedetomidine as a loading dose of 0.5 μg/kg over 10 min followed by infusion 0.3 μg/kg/h during surgery and continued for the first 48 postoperative hours. Group C: The patients received an equal amount of normal saline. The medication was prepared by the nursing staff and given to anesthetist blindly. The collected data included the heart rate, systolic and diastolic arterial blood pressure, incidence, onset, severity and treatment of paradoxical hypertension, fentanyl dose and end-tidal sevoflurane concentration, amount of blood loss and urine output. Main Results: The heart rate, systolic and diastolic blood pressure decreased significantly with dexmedetomidine than Group C (P < 0.05). The incidence and severity of the paradoxical hypertension was lower with dexmedetomidine than Group C (P = 0.011, P = 0.017, respectively). The onset the paradoxical hypertension was earlier in Group C than dexmedetomidine (P = 0.026). The dose of fentanyl and sevoflurane concentration decreased significantly with dexmedetomidine (P = 0.034, P = 0.026, respectively). The blood loss decreased with dexmedetomidine (P = 0.020) and the urine output increased with dexmedetomidine (P = 0.024). The incidence of hypotension and bradycardia was more with dexmedetomidine (P < 0.05). Conclusion: Dexmedetomidine is safe in pediatric patients undergoing aortic coarctation repair. It minimized the incidence and severity of paradoxical hypertension. It decreased the required antihypertensive medications.

The myocardial protective effect of dexmedetomidine in high‑risk patients undergoing aortic vascular surgery.

Objective: The aim of the study was to assess the effect of dexmedetomidine in high‑risk patients undergoing aortic vascular surgery. Design: A randomized prospective study. Setting: Cairo University, Egypt. Materials and Methods: The study included 150 patients undergoing aortic vascular surgery. Intervention: The patients were classified into two groups (n = 75). Group D: The patients received a loading dose of 1 μg/kg dexmedetomidine over 15 min before induction and maintained as an infusion of 0.3 μg/kg/h to the end of the procedure. Group C: The patients received an equal volume of normal saline. The medication was prepared by the nursing staff and given to anesthetist blindly. Measurements: The monitors included the heart rate, mean arterial blood pressure, central venous pressure, electrocardiogram (ECG), serum troponin I level, end‑tidal sevoflurane, and total dose of morphine in addition transthoracic echocardiography to the postoperative in cases with elevated serum troponin I level. Main Results: The dexmedetomidine decreased heart rate and minimized the changes in blood pressure compared to control group (P < 0.05). Furthermore, it decreased the incidence of myocardial ischemia reflected by troponin I level, ECG changes, and the development of new regional wall motion abnormalities (P < 0.05). Dexmedetomidine decreased the requirement for nitroglycerin and norepinephrine compared to control group (P < 0.05). The incidence of hypotension and bradycardia was significantly higher with dexmedetomidine (P < 0.05). Conclusion: The dexmedetomidine is safe and effective in patients undergoing aortic vascular surgery. It decreases the changes in heart rate and blood pressure during the procedures. It provides cardiac protection in high‑risk patients reflected by decreasing the incidence of myocardial ischemia and serum level of troponin. The main side effects of dexmedetomidine were hypotension and bradycardia.

Conventional hemofiltration during cardiopulmonary bypass increases the serum lactate level in adult cardiac surgery.

Objective: To evaluate the effect of hemofiltration during cardiopulmonary bypass on lactate level in adult patients who underwent cardiac surgery. Design: An observational study. Setting: Prince Sultan cardiac center, Riyadh, Saudi Arabia. Participants: The study included 283 patients classified into two groups: Hemofiltration group (n=138), hemofiltration was done during CPB. Control group (n = 145), patients without hemofiltration. Interventions: Hemofiltration during cardiopulmonary bypass. Measurements and Main Results: Monitors included hematocrit, lactate levels, mixed venous oxygen saturation, amount of fluid removal during hemofiltration and urine output. The lactate elevated in group H than group C (P < 0.05), and the PH showed metabolic acidosis in group H (P < 0.05). The mixed venous oxygen saturation decreased in group H than group C (P < 0.05). The number of transfused packed red blood cells was lower in group H than group C (P < 0.05). The hematocrit was higher in group H than group C (P < 0.05). The urine output was lower in group H than group C (P < 0.05). Conclusions: Hemofiltration during cardiopulmonary bypass leads to hemoconcentration, elevated lactate level and increased inotropic support. There are some recommendations for hemofiltration: First; Hemofiltration should be limited for patients with impaired renal function, positive fluid balance, reduced response to diuretics or prolonged bypass time more than 2 hours. Second; Minimal amount of fluids should be administered to maintain adequate cardiac output and reduction of priming volumes is preferable to maintain controlled hemodilution. Third; it should be done before weaning of or after cardiopulmonary bypass and not during the whole time of cardiopulmonary bypass.