Aortic valve replacement-surgical techniques, Biology

Assignment Help:

Aortic Valve replacement :  The initial steps of the operation have been described earlier. Ascending aorta is cannulated. A single two-stage atrio-venous cannula is inserted through the right atrial appendage to IVC. Cardio plegia cannula is inserted into the ascending aorta and a retrograde cardioplegia cannula into the coronary sinus. A left sided vent is inserted through the right superior pulmonary vein. Aorta is clamped at moderate hypothennia (280C). If there is no aortic regurgitation, antegrade blood cardioplegia is given in the aortic root. Ice slush is applied in the pericardiurn to give additional myocardial protection. After heart is arrested, the rest of the cardioplegia is given retrograde. Hypertrophied ventricles need additional infusion of cardioplegia. If there is aortic regurgitation, the aorta is opened and direct antegrade cardioplegia is administered by cannulating the ostia with special hand held coronary arterial perfusion cannulae. A transverse aortotomy 15 mms above the origin of right coronary artery or an oblique one extending on to the non coronary sinus of aorta is made and stay sutures are taken. Lower aortotoiny flap is retracted and aortic valve is inspected. It is excised one cusp at a time leaving 2mm rim for suturing. When the valve is calcified, it has to be removed piece meal. A wet gauze piece is used to pack the inside of left ventricle to collect loose bits of calcium. Using a sharp knife, scissors or a bone rongeur calcium will have to be removed carefully taking precaution over the anterior mitral leaflet and the septum new the AV bundle (under the comrnissure between light and non coronary cusps). The gauze piece from LV is removed. Aorta and LV are washed with saline that is sucked out. Wet peanut gauze is used to clean the areas from where calcium has been removed. Valve orifice is measured and appropriate 'sized valve is chosen.

 


Related Discussions:- Aortic valve replacement-surgical techniques

Ecotone - nature and structure of community, Ecotone - Nature and Structure...

Ecotone - Nature and Structure of Community The zone of vegetation separating two different types of communities is called ecotone. It is also known as a transition zone. The

Water-soluble vitamins for school children and adolescents, Determine Water...

Determine Water-soluble vitamins needs of school children and adolescents? The suggested requirements are given in Table 15.2 (ICMR 1990). Thiamine is computed as 0.5 mg/1000 K

Define about the ultraviolet rays - carcinogenic, Define about the Ultravio...

Define about the Ultraviolet rays - carcinogenic? Ultraviolet rays: There is ample evidence from epidemiological studies that ultra violet rays derived from the sun induce an i

Define absorption, Define Absorption, Storage and Elimination of Riboflavin...

Define Absorption, Storage and Elimination of Riboflavin? Riboflavin is absorbed from the small intestine through the portal vein and is passed to all tissues via general circu

Name three major groups into which mammals are divided, What are the three ...

What are the three major groups into which mammals are divided? The three groups into which mammals are divided are: monotremes (or prototherian, e.g., platypus), marsupials (o

List the tissues of pancreas, Q. List the tissues of pancreas? The panc...

Q. List the tissues of pancreas? The pancreas is made up of two types of tissue: The exocrine tissue secretes digestive enzymes. These enzymes are secreted into a network of

Lipids - digestion process, Lipids are essential fats that have much import...

Lipids are essential fats that have much importance to the human body. Lipids are biological molecules that are insoluble in aqueous solutions and soluble in organic solvents are c

What is biodiversity, Q. What is biodiversity? The Biological diversity...

Q. What is biodiversity? The Biological diversity is the variety of species of living beings of an ecosystem. In the ecosystems which are more biodiverse, like tropical forests

Define the postsynaptic potential in neuron a, Neuron A is a healthy neuron...

Neuron A is a healthy neuron with all the usual ion channels.  When at rest with a membrane voltage of R millivolts, neuron A produces no action potentials.  The voltage thres

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd