Heart Pump Lab

The stimulus generated by the sinoatrial node of the heart is propagated as a wave of depolarization and stimulates both atria. The depolarization wave produces a current wave of atrial contraction. After a pulse of about 1/10 of a second, the atrial depolarization wave reaches the atrioventricular node, which is situated between the two sets of chambers. The electrical stimulus passes then from the atrioventricular node through the bundle of His to the atrioventricular bundle branches, and the Purkinje fibers, which initiate the ventricular depolarization. The ventricles then repolarize until it reaches it resting state. The depolarization and repolarization can be view through the use of an electrocardiogram.

The electrocardiography is a technique of recording the bio-electric currents generated by the heart. The graphical display of this

The next step involved the palpatory method. First the subject rested his/her arm on resting table. I wrapped the cuff snugly around the upper arm as in the auscultatory method. Use one hand and palpated the radial pulse in the wrist and slowly inflated the cuff up to 20mmHg above the radial pulse was first lost. Then slowly reduced the pressure in the cuff using the exhaust valve and recorded the cuff pressure at which the first radial pulse is felt. This is the systolic pressure. Repeated the palpatory method three times and get the average of systolic pressure.

In the temporal pulse and radial pulse were easily recorded because it exposed the vein in which the blood is being pumped. The posterior tibial pulse is harder to record because the ankle doesn’t have the vein exposed unlike the vein in the wrist. The temple, wrist and ankle are positions that recorded to have a soft pulse and regular rhythmicity while the upper neck or carotid pulse, while having firm pulsing, have increasing pulse rates. The increasing in pulse rates because blood is continuous being pump pass the upper neck to transport nutrients to the brain and sending hormones throughout the body from the pituitary gland.

Dropped perpendicular lines from the arrow-point of each of the three vectors into the triangle. The three perpendicular lines intersected at one point within the triangle. Then figured out the midpoint of the triangle by drawing lines through the midpoint of each side. Draw a line from this midpoint of the triangle to the intersection point of the three perpendicular lines. This is the resultant vector of the three vectors determined for the QRS complexes of the Leads I, II and III, and corresponds to the electrical axis of the heart of the subject. Using a protractor, calculated the angle of the resultant vector from a horizontal line through the midpoint of the triangle.

In the electrocardiogram experiment, the graphs are attached. In Lead I, Q is equal to -0.03mV, R is equal to 0.469mV and S is equal to 0.021mV, with obtained average of 0.49mV. In Lead II, Q is equal to -0.017mV, R is equal to 0.660mV and S is equal to 0.006mV, with the obtained average of 0.649mV. In Lead III, Q is equal to -0.027mV, R is equal to 0.301mV and S is equal to -0.006mV, with the obtained average of 0.268mV.

The measurement of blood pressure is preferred to pulse which is the rhythmic expansion of an artery that is caused by ejection of blood from the ventricle and the result of the pressure wave induced in the arterial circulation. The pulse is taken to determine the rate of the heart beat. A normal person has a hear rate of 70beat/min. Blood pressure and pulse in normal person may be affect by changes in posture such as differing gravitational effects on circulatory system with changes in body position and physical activities such as exercise. Pulse rate also increase due to sympathetic stimulation as well. To get more accurate reading of the blood pressure, the body should be in a supine position where the arteries are at the same level as the heart. (Parati, 1989)

Some topics in this essay:
III ECG, Lead III, Son Hoang’s, , Hg Gently, Lead II, II III, blood pressure, III Using, V5 V6, ECG QRS, systolic pressure, pulses minute, lead ii, rhythmicity soft tension, pulse rate, rhythmicity soft, electrical axis, soft tension, radial pulse, 72 pulses, pulse regular rhythmicity, 72 pulses minute, regular rhythmicity soft, electrical axis heart,