Support

In cardiac anesthesia, we see invasive and aggressive mechanical support devices. An intra-aortic balloon pump, shown above, is a balloon in the aorta that assists the heart in pumping blood during systole and filling the coronary arteries during diastole. It is timed to the EKG, placed in the leg, and snaked up, almost like the stents from the previous post. Understanding the device, as well as the potential complications, how it works, and when it may help, is essential to providing anesthesia to patients who have them or might get them.

Occasionally, patients have hearts that simply cannot pump blood forward adequately, despite pharmacologic motivation and balloon pumps. We sometimes place ventricular assist devices which act like the heart, sucking blood from the ventricle and pumping it out into the body. Since the device provides most of the work and gives a continuous rather than pulsatile flow, the patient has no pulse. The heart isn't even entirely necessary. Indeed, occasionally the aortic valve is sewn shut (we do this if the patient has an incompetent valve since we don't want the device delivering blood that simply goes back to the ventricle). Simple things like blood pressure, oxygen saturation, and other monitors may not work. Placing lines requires ultrasound guidance. Sometimes these are bridges to patients getting a transplant.

Image of intra-aortic balloon pump is in the public domain, from Wikipedia.