Geriatric considerations - Cardiac: Nursing

Geriatrics is the branch of medicine that deals with the physiology and psychology of aging, as well as the diagnosis and treatment of diseases affecting older clients. Now, aging affects various organ systems, one of which is the cardiovascular system. All right, now let's start by reviewing the physiology of the cardiovascular system, which consists of the heart and the blood vessels. The heart is a muscular pump that sits in the middle of the chest cavity, between the two lungs, and on top of the diaphragm. Now, let’s take a closer look at the inside of the heart, which consists of four chambers and four valves. Deoxygenated blood coming from the superior vena cava and inferior vena cava enters the right atrium, and then passes through the tricuspid valve into the right ventricle. The right ventricle pumps the blood out the pulmonary valve and into the pulmonary arteries which carry the blood to the lungs. Here, the blood gets oxygenated and is then sent back to the left atrium, which moves the blood through the mitral valve and into the left ventricle.

Finally, blood in the left ventricle gets pumped out through the aortic valve out to the aorta, which branches into smaller arteries to supply tissues around the body. Okay, so, blood moves around the heart as it alternates between systole, a period of contraction and emptying of the heart chambers, and diastole, a period of relaxation and filling. The heart’s contractions also create pressure in the arteries, so systolic blood pressure is the pressure in the arteries when the heart is contracting and squeezing out blood, and diastolic blood pressure is when the heart is filling up with more blood. Now, the heart's contractions are regulated by its conductive system, which consists of a group of specialized cells that are capable of transmitting electrical signals. The main component of this system is the sinoatrial or SA node, also known as the pacemaker of the heart. This node initiates electrical impulses that stimulate the contraction of the heart. Additionally, the physiology of the heart is related to three parameters: heart rate, stroke volume, and cardiac output. Heart rate is the number of beats per minute, whereas stroke volume is the amount of blood pumped from the left ventricle with each beat.

On the other hand, cardiac output is the amount of blood pumped from the left ventricle per minute, and it’s calculated by multiplying the heart rate by the stroke volume. Finally, the other part of the cardiovascular system is the blood vessels, which include both arteries and veins. Now, various risk factors worsen the effects of aging on the cardiovascular system. These include smoking, a sedentary lifestyle, poorly controlled hypertension, as well as diabetes, obesity, and hyperlipidemia. Effects of aging on the cardiovascular system can involve both structure and function. Changes in the structure include loss of myocardial elasticity, which can lead to decreased cardiac compliance, which is when the ability of the ventricles to expand as they fill up with blood is impaired. This can ultimately decrease cardiac reserve, meaning there’s a decreased ability to produce the cardiac output needed to meet the demands of physical activity or stress. These changes also increase the risk for heart failure, where the heart becomes unable to pump enough blood to meet the body’s requirements. Valvular rigidity can also be present, which can lead to fatigue, palpitations, dizziness, and even syncope.

Fibrosis of the conductive system, as well as a decrease in the number of SA node pacemaker cells, results in a diminished response to adrenergic stimulation. This can be reflected in an electrocardiogram, or ECG, including a prolonged P–R interval, decreased amplitude of the QRS complex, along with bradycardia or arrhythmias. Regarding the blood vessels, decreased elastin in the vessel walls causes stiffening of large arteries, resulting in increased systolic blood pressure. There can also be narrowing of the systemic arteries due to build up of atheromatous plaque, which can impair tissue perfusion. Increased venous tortuosity may present with enlarged, twisted superficial veins, particularly in the lower limbs. Lower limb veins may also have less functional valves, resulting in the pooling of blood in those veins. Now, let’s move onto client and family teaching. Begin by teaching your client how to modify risk factors of cardiovascular disease. Encourage them to eat a healthy diet that includes a wide variety of fruits, vegetables, proteins, and whole grains, while limiting trans and saturated fats, sugars, and added salt. Also talk to them about the importance of maintaining regular activity, as tolerated, with a goal of 150 minutes weekly. Be sure to underscore how attention to both diet and exercise can help them maintain a healthy weight.