ABSTRACT
In Off Pump Coronary Artery Bypass [OPCAB] surgery, there is a high incidence of deterioration in lung mechanics and arterial oxygenation. This study aimed at assessing the effect of alveolar recruitment on lung mechanics and oxygenation in patients undergoing OPCAB surgery. In this study, we performed a randomized controlled trial between 2 groups of patients undergoing OPCAB surgery. Group A: patients received a PEEP of 5 cm H20 only. Group 3: Alveolar Recruitment Strategy [ARS] was applied after finishing the proximal anastomotic procedure and repeated in the postoperative period in the ICU. The ARS consisted of raising the peak inspiratory Pressure [PIP] to 30 cm H20 and setting PEEP at 10 cm H20 and maintaining them for 1 minute. Then, both PIP and PEEP were increased to 40 and 15 cm H20 respectively and maintained for another minute. After arrival to the ICU, all patients received 5 cm H20 PEEP, then after 1 hour, the patients received either PEEP only or with the same previous strategy as in O.R. to their groups. In the OR, lung compliance as well as arterial oxygenation were measured after induction of anesthesia, before, and after setting both PEEP and ARS. In the ICU, arterial oxygenation was measured before both PEEP and ARS, as well as one and four hours later. Postoperative pulmonary complications including hypoxemia, hypercapnia, atelectasis, prolonged intubation, pulmonary congestion, pulmonary infection, total ICU stay and mortality werq recorded. There was a significant rise in lung compliance and arterial oxygenation in the ARS [Group B] than in the PEEP group [Group A]. As regards the Arterial Oxygen Tension, there was a continuous statistically significant rise in group B than in group A, 30 minutes after starting the ARS in the OR, before starting the ARS in the ICU, 30 minutes, 1 and 4 hours later [206.5 +/- 23.9,192.2 +/- 23.5, 250.7 +/- 31.9, 211.9 +/- 21.3 mmHg and 195.3 +/- 24.5 mm/Hg respectively in group B versus 126.9 +/- 10.1, 128.7111.6, 129.1 +/- 10.4, 129.8 +/- 9.4 mmHg and 130.1 +/- 9.7 mm/Hg respectively in group A] [P< 0.0001]. Additionally, there was a marked reduction in the postoperative hypoxemia, hypercarnia, atelectasis, prolonged intubation, infection and prolonged ICU stay in the ARS group. OPCAB patients in whom there is a reduction in lung compliance owing to the large volumes of intravenous fluids and compression of the right chest by the rotated heart during revascularization of the postero-lateral coronary vessels, applying an ARS in those patients greatly improves lung mechanics and arterial oxygen tension
Subject(s)
Prognosis , Diagnostic Techniques and Procedures , Postoperative Period , Anesthesia Recovery Period , Intraoperative PeriodABSTRACT
Background: There is a considerable number of patients who are sent directly from the catheterization lab. to undergo CABG surgery and are still on Clopidogrel pretreatment. This study was done to evaluate the impact of preoperative continuous use of Clopidogrel on the amount of bleeding, the value of platelet function testing and the need for platelets use in the intra and postoperative periods following Off-Pump Coronary Artery Bypass Graft surgery [OPCAB]
Patients and Methods: 100 consecutive ischemic heart disease patients were submitted for primary isolated Off-pump coronary artery bypass graft surgery [OPCAB]. Patients were categorized into 2 groups: Group A contained 50 patients who underwent surgery while receiving continuous preoperative clopidogrel [taking at least 75 mg/day clopidogrel]; Group B included another 50 patients in whom clopidogrel was stopped at least 1 week before their CABG surgery. The preoperative as well as the in-hospital postoperative patient data were prospectively collected and comparatively evaluated. Prothrombin time, partial thromboplastin time, platelet count and platelet function were measured in the preoperative period, before heparinization, after protamine administration and then 2 hours postoperatively. The evaluation included the amount of postoperative bleeding, coagulation profile, the need for transfusion of platelets and/or whole blood; platelet dysfunction as done by Aggregometry as well as the need for surgical re-exploration to achieve hemostasis
Results: In group A, 30 patients [60%], had platelet dysfunction and in the other 20 patients [40%], platelet function was normal. Bleeding occurred in 25 patients [50 %] who required platelet and blood transfusions as detected clinically. 10 patients required re-exploration. In group B, platelet dysfunction was only in 3 patients [6 %] and platelet transfusion stopped bleeding in 1 patient and another 1 returned to the OR. Transfusion requirements were higher in group A than in Group B where total platelet units required were 14.6 +/- 2.8 and 7.3 +/- 1.9 units respectively [P<0.05]
Conclusion: The preoperative continuous use of clopidogrel until OPCAB surgery is associated with increased postoperative blood loss with the consequences of raised incidence of platelets and other blood product transfusions. Aggregometry is a good predictor for intra and postoperative bleeding and may be a useful guide for platelet transfusion in patients under Clopidogrel pretreatment
ABSTRACT
Background: Neuropsychological dysfunction is a major complication of thoracic aortic surgery with hypothermic circulatory arrest [HCA]. Magnesium has been shown to have neuroprotectant effect in acute stroke and in short term neurological dysfunction after cardiopulmonary bypass. We sought to study the effect of magnesium on the neuropsychological function after HCA for aortic arch surgery using retrograde cerebral perfusion [RCP]
Methods: Forty patients scheduled for elective thoracic aortic surgery including the arch using HCA with RCP were randomly assigned to two equal groups. The magnesium group received magnesium sulfate to increase plasma magnesium level between 1.5 to 2 folds throughout the operation and for 24 hours, while the placebo group received normal saline over the same period as a control. The patients' neurocognitive state was assessed by cognitive P300 visual evoked potentials and the revised Wechsler Adult Intelligence Scale done the day before the operation and 2 weeks postoperatively. P300 was assessed as area under the curve [AUC] between 280 and 600 ms and center of this area [Ct [time], Cv [voltage]]. The ratio of these parameters acquired by target [TG] and non-target [NTG] stimulus [TG/NTG], was calculated to assess concentration on TG stimulus and defined as concentration index [CI: CI[AUC], CI[Ct], and CI[Cv]]
Results: There were no stroke, seizure, or hospital mortality in either group. Preoperatively, in the magnesium group, AUC and Cv acquired by TG stimulus in both Cz and Fz leads were significantly altered postoperatively [P value <0.05]. In the placebo group, no significant postoperative change was observed in all leads on TG stimulus. Postoperative CI [Ct] in the placebo group, were significantly impaired in all leads. The revised Wechsler Adult Intelligence Scale shows significant decline between baseline and postoperative scores in three subtests [digit span P value <0.05, arithmetic, and picture completion P value <0.01] for magnesium group and four [digit span, arithmetic, picture completion, and picture arrangement P value <0.01] for placebo group. Statistical difference between groups in test score changes was found in one subtest [picture arrangement P value <0.05]
Conclusion: Magnesium administration in patients undergoing aortic arch surgery with hypothermic circulatory arrest using retrograde cerebral perfusion did not affect the neurocognitive outcome assessed by cognitive P300 visual evoked potentials and the revised Wechsler Adult Intelligence Scale, further work is needed to prove any protective value for magnesium in this context
ABSTRACT
Background: Many adult patients require temporary inotropic support after cardiac surgery. However, cardiac displacement and manipulation during OPCAB may cause some hemodynamic alterations. So, prophylactic usage of inotropic agents would be mandatory even in patients with normal left ventricular function. The aim of our study is to compare between levosimendan and ephedrine-calcium as inotropic agents during OPCAB in patients with normal left ventricular function
Methods: 24 patients with normal ventricular function included in this randomized controlled trial, were divided into 2 groups: Group A [n=12] received ephedrine-calcium boluses immediately prior to revascularization. Group B [n=12], received 12ug/kg of levosimendan over a period of 15 minutes, immediately after induction of anesthesia. The heart rate, cardiac index, stroke volume index, and left ventricular ejection fraction were measured before and 10 and 60 minutes after the drugs administration as well as 2 hours postoperatively
Results: Heart rate was significantly higher in the calcium-ephedrine group than in the levosimendan one after 10 and 60 minutes from the beginning of revascularization [P<0.05]. Compared with ephedrine-calcium group, cardiac index was significantly higher 10, 60 minutes and 2 hours postoperative [p< 0.05] after administration of levosimendan. Stroke volume index was significantly higher 10 minutes after levosimendan administration [p< 0.05]. Left ventricular ejection fraction increased significantly after 60 minutes, and 2 hours postoperative in the levosimendan group [P<0.05]
Conclusion: Levosimendan in a dose of 12 ug/kg over a period of 15 minutes enhances the left ventricular performance during off-pump coronary artery bypass grafting in patients with normal preoperative left ventricular function, better than calcium-ephedrine with neutral effect on myocardial energy