Persufflation (gaseous oxygen perfusion) as a method of heart preservation.

Persufflation (PSF; gaseous oxygen perfusion) is an organ preservation technique with a potential for use in donor heart preservation. Improved heart preservation with PSF may improve outcomes by maintaining cardiac tissue quality in the setting of longer cold ischemia times and possibly increasing the number of donor hearts available for allotransplant. Published data suggests that PSF is able to extend the cold storage times for porcine hearts up to 14 hours without compromising viability and function, and has been shown to resuscitate porcine hearts following donation after cardiac death. This review summarizes key published work on heart PSF, including prospective implications and future directions for PSF in heart transplantation. We emphasize the potential impact of extending preservation times and expanding donor selection criteria in heart allotransplant. Additionally, the key issues that need to be addressed before PSF were to become a widely utilized preservation strategy prior to clinical heart transplantation are summarized and discussed.

A femoral artery cannula that allows distal blood flow.

OBJECTIVE: A femoral artery cannula is used for certain types of circulatory support but can cause ischemia, especially during prolonged perfusion. This study tests the function of a femoral cannula designed to allow proximal and distal blood flow. METHODS: Five pigs were used in the study. In each animal a distal-flow cannula was implanted in the femoral artery of one leg, and the same-sized standard cannula was implanted in the other. Blood was drained from the left atrium and delivered to the femoral artery through the distal-flow cannula or standard cannula by using a centrifugal pump. An ultrasonic flow probe and microspheres were used to quantify flow and perfusion distal to the cannula. RESULTS: Distal femoral flow and tissue perfusion were present in all animals (5/5) with the distal-flow cannula but only in 1 of 5 animals with the standard cannula (P < .048). Distal flow did not change with pump flow. Mean distal flow at each level of pump flow was higher with the distal-flow cannula (P < .05). Tissue perfusion was also higher with the distal-flow cannula (0.052 +/- 0.028 vs 0.010 +/- 0.022 mL x min(-1) x g(-1), P < .03). CONCLUSIONS: In the swine model the distal-flow cannula allowed greater and more consistent distal flow than the standard cannula. The use of a distal-flow cannula for circulatory support might reduce the risk of distal limb ischemia.

Limited-access surgical coronary artery revascularization.

The continued evolution of surgical revascularization has resulted in much less invasive alternatives for patients undergoing coronary artery bypass grafting. In particular, techniques and technologies have been developed to allow for the grafting of coronary arteries through limited access incisions without the circulatory support of cardiopulmonary bypass. The conduits are generally arterial rather than the venous alternatives used originally, and the harvesting of these conduits is performed through limited access incisions described in another article in this review. The result of these efforts is sternal-sparing solutions for the off-pump coronary artery bypass grafting of all the various coronary locations on the heart. This is accomplished through a spectrum of small incisions that can directly expose any specific area of interest for focal bypass grafting. The surgical insult is greatly reduced and the patient's recovery is significantly enhanced. These efforts continue to bring us closer to the ultimate goal of 24-hour hospital stays for coronary artery bypass grafting patients.

Facilitated vascular anastomosis in coronary bypass surgery.

The goal of truly minimally invasive surgical revascularization with 1-day hospital stays is shared by surgeons, patients, and payors alike. However, accomplishing this will involve doing surgery through more limited-access incisions and working within closed spaces. Suture management in this setting is cumbersome, slow, and unreliable. Facilitated anastomotic techniques and technologies are generally believed to be the vehicle that will ultimately allow us to address this. A considerable amount of time and resources has already been expended by many people and companies in this effort, with early clinical progress now being reported. Much more remains to be done, and other new approaches still need to be investigated. This article provides an overview or snapshot of the work and progress to date with facilitated vascular anastomoses along with some of the challenges that have yet to be solved. The achievement of a predictable, reproducible, and reliable technique to accomplish this will significantly and irrevocably reduce the extent of surgery required to revascularize the heart.