Intra-aortic balloon counterpulsation is a simple cardiac assist method applied in acute heart failure of all causes and in intractable angina pectoris where drug therapy has failed, and in surgical use mainly in intractable low cardiac output. IABP can be actively used after the development of ventricular fibrillation during nonstop bypass surgery.
There are many causes of ventricular fibrillation during nonstop bypass surgery, mainly including prolonged temporary block of coronary arteries or inadequate establishment of collateral circulation, compression of the fixator affecting normal cardiac contraction and coronary blood supply, moving the heart causing a decrease in per-pulse output and affecting coronary blood supply, and disturbance of the internal environment, which are common and serious complications during nonstop bypass surgery.
IABP is a temporary mechanical circulatory assist method widely used in clinical practice. Its working principle is to place a balloon connected to an external air source at the proximal end of the descending aorta, which rapidly decompresses and atrophies before the heart contracts and the aortic valve opens. This results in instantaneous intra-aortic decompression, which reduces aortic valve opening pressure and left ventricular pulsatile resistance. In 1962, Moulopoulos et al. first applied IABP successfully in animal experiments, and in 1968, Kantrowitz et al. successfully applied it in clinical practice, and since then IABP has become a routine method in the treatment of coronary artery disease. Since then, IABP has become a routine method in the treatment of coronary artery disease.
In the event of ventricular fibrillation during nonstop bypass, the first treatment measure should still be the rapid establishment of CPB assist, and the use of IABP should be actively considered, rather than a fluke waiting mentality. Because of the lack of awareness, IABP assisted late and affected the prognosis. One case was unable to get off CPB because of repeated attempts to use IABP after going offline; the other two cases both had severe LOS combined with ARF, and one of them died 7 d after surgery. In other cases, IABP was installed before adjusting CPB flow, and the results were significantly better.
At present, the application of IABP in the clinic is mostly a rescue measure, and the loss of the timing of its use leads to poor clinical outcomes. We believe that IABP is an active treatment rather than a rescue measure, and that early use, especially preoperative application in critically ill patients, can lead to better outcomes, rather than preoperative placement after the hasty establishment of extracorporeal circulation after intraoperative ventricular fibrillation.
Our experience is that the application of IABP should be actively considered in the presence of.
1, those with intractable angina with deteriorating cardiac function.
2, Those who decide to perform emergency surgery.
3, those who have been preoperatively administered moderate doses of positive inotropic drugs.
4.OPCAB surgery is expected to be poorly tolerated by intraoperative cardiac mobilization.
5, those with serious preoperative complications, such as septal perforation.
6, those who develop arrhythmias related to cardiac function that are not easily controlled. However, active early application after emergencies can still have some effect.
During the use of IABP, the monitoring of ACT is crucial. If the postoperative drainage increases, the ACT time should not be reduced, and increasing the plasma input as well as the necessary open-heart hemostasis is the fundamental method to solve the problem.
The main concern in clinical practice regarding the application of IABP is the high rate of complications, which according to Kantrowitz’s definition of complications can occur in up to 45%, but only 4% actually occur and leave functional impairment or cause death.
Our experience in this regard is that
1, choose a catheter with a relatively small diameter and place it without a sheath puncture if necessary.
2.Bilateral external iliac artery and femoral artery ultrasound should be routinely performed before surgery to clarify the vascular status.
3, for patients with severe coronary artery disease, a femoral artery puncture tube should be routinely left in place during anesthesia.
4.Monitoring of the dorsalis pedis artery and lower extremity blood flow.
5.The IABP should be removed as early as possible when normal hemodynamics can be maintained with conventional doses of positive inotropic drugs.
The adjuvant effect of IABP on the heart is also limited, and the indications for its use should be mastered in extremely ill patients. In this group, the application of IABP is not satisfactory in those who have not achieved good results with the application of high-dose antihypertensive drugs, and such patients should consider the use of left-heart adjuvant or whole-heart adjuvant. We have tried left-heart assist and whole-heart assist in critically ill patients, and our experience needs to be further summarized.
Intra-aortic balloon counterpulsation is a safe and proven circulatory assist modality, and its active application in high-risk coronary patients, especially after ventricular fibrillation during nonstop bypass surgery, can significantly improve the therapeutic outcome.