الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Results of cardiac operative procedures continue to improve despite rever-increasing numbers of older and sicker patients. Of those who die, many do so of complications relating to low cardiac output during the perioperative period. The intra-aortic balloon pump (IABP) has been widely used during the perioperative period to support patients with low cardiac output. The IABP was first used clinically in 1968 for supporting patients with cardiogenic shock after acute myocardial infarction. Soon its use was expanded to postoperative support and as an aid in weaning patients from cardiopulmonary bypass. Use of the IABP has continued to increase, particularly over the past decade with the expansion of interventional cardiology, and the increasing age and acuity of cardiac surgical patients.
The physiologic approach to optimal therapeutic management of myocardial ischemia must be directed toward reduction of left ventricular afterload and left ventricular wall tension to reduce myocardial oxygen consumption augmentation of myocardial perfusion with normal distribution of flow through augmentation of coronary blood flow and lowering left ventricular end diastolic pressure (LVEDP) which improves subendocardial perfusion and myocardial oxygen supply and maintenance of physiologically adequate systemic cardiac output through improvement in ventricular performance .
High-risk coronary patients have an increased likelihood of developing low cardiac output following myocardial revascularization.
So, in recent years, a number of published studies have expanded the potential clinical applications of IABP, to include its use as a
preoperative support for high-risk patients who require coronary artery bypass graft (CABG) surgery.
The use of intra-aortic balloon counter pulsation (IABC) to reduce left ventricular afterload and myocardial oxygen consumption is clearly indicated in patients with refractory myocardial ischemia or acute myocardial infarction complicated by cardiogenic shock. However, the ability of IABC to increase diastolic antegrade coronary blood flow through critically stenosed coronary arteries is not well substantiated. Therefore, the role of “prophylactic” IABC in hemodynamically stable patients with severe coronary artery disease undergoing surgical revascularization remains controversial.
So, the purpose of our study was to evaluate the use of preoperative elective IABP in a poor left ventricular function patients and comparison of the outcome of CABG surgery in those patients with another group of poor left ventricular function patients in whom the balloon was not inserted preoperatively.
We studied 40 poor left ventricular function patients with coronary artery disease underwent myocardial revascularization (CABG), those patients were randomized into either of two groups; group I (n=20) in whom preoperative IABP was used and group II (n=20) which did not receive preoperative IABP.
The intraaortic balloon was inserted primarily by the percutaneous seldinger technique. Open transfemoral technique was used only when the percutaneous technique failed. The intraaortic balloon used was a Datascope True sheathless DL-7.5 Fr. 40 CC IAB catheter connected to a Datascope pump .
The position of the balloon was confirmed by transoesophageal echocardiography (if available) in patients were the balloon was inserted in the operating theatre and by chest X-ray in patients getting IABP in ICU.
All operations were performed through a median sternotomy. The patients were heparinized with an initial dose of 3 mg/kg of heparin and periodically supplemented to mai maintain an activated clotting time of more than 400 seconds.
The aorta was cannulated in the standard fashion. Ascending aorta venting was performed through a catheter with a Y connector to the cardioplegic line. Cardiac drainage was realized through the atrial appendage using a No. 36 two-stage cavoatrial catheter.
Patients with IABP, close observation to lower extremities for any changes including pulses, temperature and colour.
Routine postoperative investigations including chest X-ray. Coagulation profile (PTT, PT, INR and ACT), complete blood picture, Strip ECG 12-head; cardiac enzymes (CK & CK-MB), SGOT, SGPT, bilirubin, urea and creatinine were done and repeated whenever needed.
Cardiac output was repeatedly measured (6, 24 and 48 hours postoperatively). Cardiac index (L/min/m2) was calculated for all patients to evaluate cardiac performance.
Ventilation time in was 24.7 + 1.80 (hr) in group I (IAB) while in group II, it was 72.40 + 19.02 (hr) (P = 0.001). The median time of pharmacological cardiac support was 40+25 hr. in group I, while it was 80+24 hr. in group II (P = 0.001).
As regard time of IABP cardiac support, the mean time for group I was 92.25+12.4 hr and 115.20+28.8 hr in group II (P = 0.001). The mean length of stay required in ICU was shorter in group I compared with group II. It was 95.20 + 5.18 (hr) versus 121.70 + 26.39 (P = 0.001).
Also, we found that the total hospital stay was significantly shorter in group I compared with group II 10.49+1.52 days versus 15.7+4.83 days (P= 0.002). IABP-related complications occurred in 3 out of 40 patients in the entire series of study (7.5%) complication rate. All cases of limb ischemia due to IAB catheter improved and showed no ischemia after removal of catheter or removal of catheter and thrombectomy. After being discharged from ICU to the ward, patients were observed in the ward until discharged from the hospital IABP has remarkable beneficial effects in patients with haemodynamic instability due to myocardial ischemia and low cardiac output syndrome but at the same time IABP is related to significant morbidity and mortality related to vascular complications due to its insertion, leg ischemia is by far the most complication , other complications include balloon rupture, thrombosis within the balloon, septicemia, infection at the insertion site, bleeding, false aneurysm formation, lymph fistula, lymphocele and femoral neurpathy.
Very few complication of IABP cause death. Rare instance of bleeding (retroperitoneal or aortic), septicemia, aortic dissection may cause or contribute to a patientʼs death
We noticed lower mortality, morbidity including (low cardiac output, perioperative myocardial infarction and ventricular arrhythemia),
shorter postoperative length of stay including (ventilation time, inotropes time, ICU stay and hospital stay) and better cardiac performance (higher cardiac index in the early 48h. postoperatively) in group I when compared with group II.