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This document is a review of the article Cannulation Strategies and Pitfalls in Minimally Invasive Cardiac Surgery by Ramchandani, Jabbari, Abu Saleh, and Ramlawi (2016). The article provided informative discussions on minimally invasive cardiac surgery (MICS) and presented the different cannulation techniques.
MICS is a very important development in the field of cardiothoracic medicine. It eliminates the inconveniences experienced during the median sternotomy and bypass circuit placement. The key in the success of MICS is the cannulation technique employed. Options for arterial cannulation in MICS include ascending aorta, femoral artery, and axillary artery. Each has its own advantages and risks. Cannulation in the ascending aorta requires the appropriate ultrasound scanning in order to locate the best site for cannulation and cross clamping. Its application in MICS is limited by the degree of access to the aorta and having a cannula in a small incision can limit site visibility. In order to have better access, partial sternotomy might be required and certain maneuvers should be executed. This type of cannulation may result to dissection, which occurs in 0.01% to 0.09% of patients. Because of the limitations of central aortic cannulation, many surgeons prefer to use cannulation in the femoral artery. Femoral artery cannulation is considered to be the most common approach since it is more convenient and provides better exposure through a limited chest incision. This is also the most commonly used type of cannulation for obese patients. However, femoral cannulation may cause certain complications such as infection, hematoma, and lymphocele, and also has a small risk of retrograde aortic dissection, embolization, and ipsilateral limb ischemia. Axillary artery, on the other hand, has the advantage of antegrade perfusion without crowding the operative filed in MICS and eliminates the risk of ipsilateral limb ischemia. This cannulation is also useful in redo MICS.
Cannulation in the femoral vein is used for the venous drainage during cardiopulmonary bypass in MICS. The use of modern three-stage cannulas offer excellent drainage and right heart decompression with the help of a kinetic drainage assist device. This cannulation however, has potential complications such as perforation of the inferior vena cava during the insertion of the cannula and air entrapment without airlock during cardiopulmonary bypass. Further, the length of the femoral vein cannula usually cause increased resistance to effective drainage. To prevent air entrapment, a vacuum-assisted device is often used.
Each type of cannulation has its advantages and risk. One may be better than the other in a certain aspect, but may be risky in another aspect. In a 10-year study on the evolution of cannulation techniques by Chan et al. (2012) with a sample of 922 study subjects, 86% had central aortic cannulation, 14% had femoral artery cannulation, and 0.4% had axillary artery cannulation. During the study period, it was observed that peripheral arterial cannulation was progressively replaced by central aortic cannulation as evidence by 33% of patients from 2000-2001, 83% of patients from 2002-2005, and 93% of patients from 2008-2010. (Chan et al., 2012) Another study also investigated cannulation in MICS and gathered eight-year data. In a sample of 910 patients, the most commonly performed cannulation is through the central aortic cannulation (84.0%). The study found that the risk of major in-hospital complications is increased in peripheral and axillary aortic cannulation in contrast to central aortic cannulation. (Iribarne et al., 2010)
Based on the studies cited in the preceding paragraph, it seems that surgeons are now leaning to employ the central aortic cannulation technique. With the statistics presented, it would be safe to assume that the advantages of central aortic cannulation outweigh its risks. As the risk of central aortic cannulation in MICS was not thoroughly discussed, it would be helpful in the improvement of knowledge on MICS if a research would investigate the advantages and risks of central aortic cannulation.
Reference:
Chan, E. Y., Lumbao, D.M., Iribarne, A., Easterwood, R., Yang, J.Y., Cheema, F.H., Smith, C.R., & Argenziano, M. (2012). Evolution of cannulation techniques for minimally invasive cardiac surgery: A 10-year journey. Innovations, 7, 9-14.
Iribarne, A., Karpenko, A., Russo, M.J., Cheema, F., Umann, T., Oz, M.C., Smith, C.R., & Argenziano, M. (2009). Eight-year experience with minimally invasive cardiothoracic surgery. World Journal of Surgery, 34, 611-615.
Ramchandani, M., Al Jabbari, O., Abu Saleh, W.K., & Ramiawi, B. (2016). Cannulation strategies and pitfalls in minimally invasive cardiac surgery. Methodist DeBakey Cardiovascular Journal, XII, 10-13.
