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80 Cards in this Set
- Front
- Back
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Cardiac Function
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-Describe the flow of blood through the heart
-Coronary Artery, Coronary Circulation |
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Systemic & Myocardial Circulation
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-Arteries and Veins
-Capillaries -Venules |
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Cardiac Output (CO)
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Amount of blood (in liters)heart puts out in a minute, ejected from the left ventricle. Normal CO is 4-6 liters/min.
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Normal Cardiac Output (CO)
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4-6 liters/minute
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What are some things that may increase CO?
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Exercise, increased activity, going up steps, fever, medication
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Cardiac Output regulation
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-cardiac index
-stroke volume -preload -afterload -rate |
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cardiac index
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Adequacy of the cardiac output for an individual. Determined by dividing cardiac output by the body surface area
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stroke volume
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amount of blood ejected from the left ventricle with each contraction.
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preload
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end-diastolic volume.
Starling's Law: more stretch on the ventricular muscle, the greater the contraction and the greater the stroke volume. |
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afterload
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resistance to the left ventricular ejection: the work the heart must overcome to fully eject blood from the left ventricle
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rate
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Cardiac output has to be dependent upon heart rate. We know, technically, that as heart rate goes up, cardiac output should go up. As heart rate goes down, cardiac output should go down. But, of course, when we talk about the diseased heart, it may be different. And, we are talking about also how high heart rate is going to be different. If your heart is beating at 180/minute, do you think you are going to have a good cardiac output? No, it’s going too fast to fill.
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Conduction System
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-Mechanical action of the heart depends on electricity
-Action potential generates a heart beat -Autonomic nervous system influences the rate of the impulses -Parasympathetic nervous system decreases the rate of impulses |
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Generally, how does the heart work?
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Impulse starts at the SA node (called the pacemaker) located in the right atrium and it will deliver impulses between 60-100 beats per minute. Then the impulse goes down to the AV node (between 40-60 beats per minute). If something happens to your SA node, we have a lot of things that can kick in to help us out. The AV node is our secondary pacemaker. (AV node assists atrial emptying by delaying the impulse before transmitting it through the bundle of His and the ventricular Purkinje network.) Then the impulse passes and goes down to the bundles and we have our right bundle branch and our left bundle branch. From there they go to the Purkinje network. This is the network that innervates entire ventricles, the right and left ventricles. Now the Purkinje fibers can also kick in if the AV node does not work, between 20-40 beats per minute.
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Electrocardiogram
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- reflects the activity of the conduction system
- Normal sinus rhythm - impulse originated from SA node and went through the normal sequence |
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P-wave
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atrial contraction, electrical conduction through both atria.
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P-R interval
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impulse from SA to AV node through the bundles and the Purkinje fibers.
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QRS
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ventricular contraction
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Q-T interval
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ventricular relaxation; time needed for ventricular depolarization and repolarization
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bradycardia
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a sinus rhythm, but slow, below 60 bpm
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tachycardia
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a sinus rhythm, but fast, above 100 bpm
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Respiratory physiology
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-respiration
-breathing -ventilation |
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Ventilation
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cycle of inspiration and expiration
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What happens after you inhale?
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Air enters nose/mouth, here the air gets warmed, moistened and filtered.
Trachea/pharynx Bronchus Left / right Bronchi Bronchioles Alveoli: this is where the gas exchange happens at the capillaries of the alveoli where by diffusion CO2 is removed and O2 is taken in |
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Work of Breathing
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-Muscles
-Compliance and Elasticity -Surface tension -Air resistance |
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Muscles
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-Diaphragm: normal breathing is usually diaphragmatic breathing.
-Accessory muscles |
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Compliance and Elasticity
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recoil ability of the lung
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Surface tension
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-elastic fibers and fluid that lines the alveoli
-controlled by surfactant |
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Control of Respiration
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-neurological
-chemical mechanisms |
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Neurological
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Pons and medulla
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Chemical mechanisms
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-respiratory centers respond to CO2 (carbon dioxide) and O2 (oxygen)
-chemoreceptors in the aortic arch and carotids respond to changes |
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Gas Exchange
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-What does the exchange of CO2 and O2 depend on?
It depends on diffusion and ventilation. You have got to have both. Anything that’s going to impair that airflow or impair that blood flow, you will see changes to CO2 and Oxygen. Here are 2 signs of impairment: -Hypoxemia -Hypercapnia |
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What does the exchange of CO2 and O2 depend on?
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It depends on diffusion and ventilation. You have got to have both. Anything that’s going to impair that airflow or impair that blood flow, you will see changes to CO2 and Oxygen.
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Hypoxemia
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low levels of arterial Oxygen
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Hypercapnia
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More than the normal level of carbon dioxide in the blood. Also called hypercarbia.
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3 Aspects of Gas Exchange
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- diffusion
- ventilation/perfusion - O2 carrying capacity |
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diffusion
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transport of oxygen and carbon dioxide across the capillaries. Diffusion is from HIGHER to LOWER concentrations.
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Ventilation/perfusion
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ventilation: process of moving gases into and out of the lungs.
perfusion: blood flow to the lungs and tissues |
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O2 carrying capacity
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Capacity of blood to carry oxygen is influenced by the amount of dissolved oxygen in the plasma, amount of hemoglobin, and tendency of hemoglobin to bind with oxygen
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Factors Affecting Oxygenation
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- perfusion issues
- ventilation issues |
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Perfusion issues
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-Conduction disturbances
-Impaired valve function -Myocardial hypoxia -Cardiac muscle condition |
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Ventilation issues
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-hyperventilation
-hypoventilation -hypoxia |
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Development Factors
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Very young and very old are vulnerable to oxygenation problems
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Infants and small kids Development Factors
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Upper respiratory problems
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Adolescents and Middle Adults Development Factors
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- Smoking is the most prominent risk factor in this group
- Inhaling substance (glue, paint) |
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Older Adults Development Factors
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- Decreased surfactant
- Pneumonia |
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Physiological Factors
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-Musculoskeletal factors
-Trauma -Neuromuscular disease -Chronic diseases |
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Environmental Factors
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-workplace exposure
-smoking -general health -nutrition -exercise -stress |
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General Assessment
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-health history
-Physical exam -diagnostic tests |
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Health history
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What are some of the things we should ask in the Health History? History of respiratory problems, anyone in the family. Do you smoke? What are their symptoms - What’s their chief complaint, coughing (color, productive, when), chest pain, fatigue. Are they on any medications? You need specifically to ask if on any OTC meds.
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Physical exam
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Generally, do a head-to-toe assessment, respirations, lung sounds.
-Look at their breathing pattern as they talk. Is it irregular? Are they huffing or puffing a lot? -Their orientation: are they woozy or disoriented? -Look at their mucous membranes, are they pale? -Listen to their abdomen: if poor oxygenation, bowel sounds are sluggish. GI system needs oxygen too and peristalsis stops or slows down when it’s hypoxic. Belly will start swelling also, so look for abdominal distention and listen for slow bowel sounds. Those are signs that the GI is not getting enough oxygen. -Look at the urine output or have them describe it because one of the signs that the kidneys are not getting enough O2 is very concentrated, odorous urine. |
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Diagnostic tests
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-Pulmonary Function Test
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Pulmonary Function Test
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-Tidal volume
-Residual volume -Functional residual capacity -Vital capacity -Total lung capacity |
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Tidal volume
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Volume of air inhaled or exhaled per breath. Normal breath. Depends on weight/size
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Residual volume
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volume of air left in lungs after a maximal exhalation
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Functional residual capacity
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volume of air left in lungs after normal exhalation
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Vital capacity
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volume of air exhaled after maximal inhalation
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Total lung capacity
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total volume of air in lungs following a maximal inhalation
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Nursing Diagnosis
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-Ineffective airway clearance
-Ineffective breathing pattern -Ineffective gas exchange |
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Nursing Goal
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- To meet the O2 needs of the client
- Teaching and Continuity of Care - Adequate Health Promotion |
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Interventions
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Meet O2 demands
-Assess and monitor -Positioning/coughing/suctioning -Ambulation -Incentive spirometry/chest PT -Oxygen -Bronchodilators/expectorants -Medications -Teach pursed lip-breathing -Reduce anxiety -Rest -Nutrition -Fluids -Controlling infection -Expansion of lungs |
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Oxygen
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-Highly combustible gas
-Nursing measures -“No smoking” signs -Electrical equipment functioning correctly and properly grounded -Fire procedures, closest fire extinguisher -Oxygen levels of portable tanks -Use water-based lubricants |
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Types of Oxygen Supplies
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-Oxygen tanks
-Permanent wall-piped system |
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O2 Flowmeter
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page 1123 of textbook, picture of O2 Flowmeter
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Methods of Oxygen Delivery
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-Nasal Cannula (NC)
-Face masks -Face mask with reservoir bag -Venturi mask |
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Nasal Cannula
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The two cannulas, about 1.5 cm (1/2 inch) long, protrude from the center of a disposable tube and are inserted into the nares
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Oxygen Masks
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-Shaped to fit snugly over the mouth and nose; secured in place with a strap
-Administer oxygen, humidity, or heated humidity -Two primary types: - delivering low concentrations - delivering high concentration |
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Simple face mask
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- short-term
- delivers oxygen concentration from 30% to 60% - contraindicated for clients with carbon dioxide retention |
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Methods of Oxygen Delivery - Venturi mask
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- delivers oxygen concentration of 24% to 55%
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Teaching and Continuity of Care: Adequate Health Promotion
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-Vaccinations (Flu and Pneumovax)
-Elimination smoking, chemicals -Nutrition -Diseases -Stress reduction -Exercise |
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Evaluation
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- Have you met the goals?
- Evaluate the degree of breathlessness - Reevaluate pulmonary tests - Notify MD if patient seems worse |
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Clients with anemia may complain of:
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1.Lack of energy. Anemia, a lower than normal hemoglobin level, is a result of decreased hemoglobin production, increased red blood cell destruction, and/or blood loss. Clients will have complaints of fatigue, decreased activity tolerance, and increased breathlessness, as well as pallor (especially seen in the conjuctiva of the eye) and an increased heart rate.
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The most common toxic inhalant that decreases the oxygen-carrying capacity of blood is:
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2.Carbon monoxide is the most common toxic inhalant that decreases the oxygen-carrying capacity of blood. The affinity for hemoglobin to bind with carbon monoxide is greater than 200 times its affinity to bind with oxygen, creating a functional anemia. Because of the bond's strength, carbon monoxide is not esaily dissociated from hemoglobin, making hemoglobin unavailable for oxygen transport.
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Conditions such as shock and severe dehydration resulting from extracellular fluid loss and reduced circulating blood volume cause:
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1.Hypovolemia. Conditions such as shock and severe dehydration resulting from extracellular fluid loss and reduced circulating blood volume cause hypovolemia. With a significant fluid loss, the body tries to adapt by increasing the heart rate and peripheral vasoconstriction to increase the volume of blood returned to the heart and, in turn, increase the cardiac output.
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Fever increases the tissues' need for oxygen, and as a result:
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2.Carbon dioxide increases. If the febrile state persists, the metabolic rate remains high and the body begins to break down protein stores, resulting in muscle wasting and decreased muscle mass. Respiratory muscles such as the diaphragm and intercostal muscles are also wasted.
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Left-sided heart failure is an abnormal condition characterized by:
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1.Impaired functioning of the left ventricle. Left-sided heart failure is an abnormal condition characterized by impaired functioning of the left ventricle due to elevated pressures and pulmonary congestion. If left ventricular failure is significant, the amount of blood ejected from the left ventricle drops greatly resulting in decreased cardiac output.
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Right-sided heart failure results from:
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1.Impaired functioning of the right ventricle characterized by venous congestion in the systemic circulation. Right-sided heart failure more commonly results from pulmonary disease or as a result of long-term left-sided failure. The primary pathological factor in right-sided failure is elevated pulmonary vascular resistance (PVR). As the PVR continues to rise, the right ventricle must generate more work, and the oxygen demand of the heart increases. As the failure continues, the amount of blood ejected from the right ventricle declines, and blood begins to "back up" in the systemic circulation. Clinically the client has weight gain, distended neck veins, hepatomegaly and splenomegaly, and dependent peripheral edema.
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Cyanosis, the blue discoloration of the skin and mucous membranes caused by the presence of desaturated hemoglobin in capillaries, is a(n):
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2.Late sign of hypoxia. Caused by the presence of desaturated hemoglobin in capillaries. The presence or absence of cyanosis is not a reliable measure of oxygenation status.
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A person who starts smoking in adolescence and continues to smoke into middle age:
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1.Has an increased risk for cardiopulmonary disease and lung cancer
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A simple and cost-effective method for reducing the risks of stasis of pulmonary secretions and decreased chest wall expansion is:
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3.Frequent change of position
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The most effective position for client with cardiopulmonary disease is the:
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4.45-degree semi-Fowler's position, using gravity to assist in lung expansion and reduce pressure from the abdomen on the diaphragm
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