Vital Signs & Oxygenation

Potter & Perry Ch. 29 & 41

Afebrile

• not feverish

• when a patient’s fever “breaks'“

Antipyretics

• an antipyretic drug

• Reduce fever

Ausculatory Gap

A temporary absence of Korotkoff sounds during blood pressure measurement. It occurs when the cuff pressure is between the systolic and diastolic pressures

Blood Pressure

The force exerted on the walls of an artery by the pulsing of blood under pressure from the heart.

• good indicator of cardiovascular health

Bradycardia

A slow rate, below 60 BPM for an adult

Capnography

Measurement of exhaled carbon dioxide

Conduction

Mechanism of thermoregulation where heat is transferred through direct physical contact from a warmer object to a cooler one.

• Heat is lost through conduction when the skin touches a colder object

• Heat is gained through conduction when the skin touches a warmer object

Convection

The process of heat loss or gain through the movement of a surrounding fluid, typically air or water, carrying heat away from or towards the body.

Core Temperature

• Temperature of the deep tissues

• Under control of the hypothalamus and remains within a narrow range

• Skin / body surface temperature fluctuates dramatically with the changing temperature outside / environmental changes

• Rectal temperature is a good way to get an accurate core temperature reading (average rectal temp for an adults is 37.5C or 99.5F)

Diaphoresis

Visible perspiration, primarily occurring on the forehead and upper thorax (although it can occur all over the body)

• Excessive evaporation causes skin scaling and itching and drying of the nares and pharynx

Diastolic Pressure

Minimal pressure exerted against the arterial walls at all times

Dysrhythmia

An interval interrupted by an early or late beat or a missed beat indicates an abnormal rhythm

• threatens the ability of the heart to provide adequate cardiac output, particularly if it occurs regularly / repetivtively

Eupnea

The normal rate and depth of ventilation

• sighing interrupts it

Evaporation

• a mechanism of thermoregulation

• cools the body by using the energy from your skin to turn liquid sweat into gas

• Removes heat, preventing overheating and maintaining a stable internal temperature

Febrile

Having or showing the symptoms of a fever

Fever

• AKA pyrexia

• occurs because heat-loss mechanisms are unable to keep pace with excessive heat production, resulting in an abnormal rise in body temperature

• Temp above 38 degrees celcius (100.4 degrees farenheit)

• Usually accompanied by other physical or cognitive signs

Heatstroke / Heat Exhaustion

Heatstroke: A potentially lethal condition with a body temperature of 40C or 104F

• accompanied by hot, dry sking and CNS abnormalities (delirium, convulsions, or coma)

Heat Exhaustion: Caused by envrionmental heat exposure and presents with profuse diaphoresis that results in excess water and electrolyte loos

• hypotension, dizziness, confusion

Hematocrit

The ratio of the volume of red blood cells to the total volume of blood

• Adults:

  • Male: 40-54%

  • Female: 36-48%

• Low Hematocrit: sign of anemia, nutritional deficiencies, chronic illness or a problem with the bone marrow

• High Hematocrit: sign of dehydration, blood disorder (bone marrow cancer), erythrocytosis, polycythemia vera, can be caused by certain medications

Hypertension

A condition in which the force of blood against the artery walls is consistently too high

• Often asymptomatic but is a major factor underlying death from heart attack or stroke

• Stage 1: Systolic from 130-139 or diastolic from 80-90

• Stage 2: systolic greater than 140, diastolic greater than 90

Hyperthermia

An elevation of the body temperature without an increase in hypothalamic set point.

• Malignant hyperthermia: a hereditary conditions of skeletal muscle and a potentially lethal complication

  • Uncontrolled heat production

Hypotension

Present when the systolic BP falls to 90 or blow.

• Some individuals just have low BP but for most it is an abnormal finding associated with illness

• Occurs because of dilation of the arteries in the vasculature, loss of substantial amount of blood volume, or failure of the heart muscle to pump adequately

• Pallor, skin mottling, clamminess, conufsion, increased HR, or decreased urine output

Hypothermia

Core body temperature of less than 35C or 95F.

• Heat loss during prolonged exposure to cold overwhelms the ability of the body to produce heat

• Slows cell metabolism

• Poor patient outcomes: increased infection complications, clotting disorders, and prolonged hospitalization

Hypoxemia

Low levels of arterial O2.

• When arterial oxygen levels fall, these receptors signal the brain to increase the rate and depth of ventilation.

Orthostatic hypotension

Occurs when a person develops symtoms (light-headedness, dizziness) and a drop in systolic pressure by at least 20 or a drop in diastolic by at least 10 within 2-5 minutes of quiet standing or 5 minutes of supine rest

• also called postural hypotension

Oxygen Saturation

The amount of hemoglobin saturated with oxygen in a patient’s blood

• Normal saturation is greater than 95%

• Saturation below 90% is considered a medical emergency

• Saturation of 75% or less is considered a critical value

Pulse Deficit

A pulse defecit is created by an inefficient contraction of the heart that fails to transmit a pulse wave to the peripheral pulse site.

• To assess measure both apical and radial pulses at the same tiem with the help of another person and see the difference

Pulse Pressure

The difference between systolic and diastolic pressure

• If BP 120/80, pulse pressure is 40

Pyrogens

Fever (pyrexia) inducing substances, or agents that cause a rise in body temperature

• they can be bacteria, fungi, viruses, cytokines (immune system)

Shivering

Involuntary body response to tempearture differences in the body.

• Skeletal Muscle movement during shivering requires significant energy

• Shivering sometimes increases heat production 4-5x greater than normal

• Heat that is produced helps equalize body temperature and then shivering ceases

Sphygmomanometer

What is used to take a manual blood pressure; blood pressure cuff

• Includes: a pressure manometer, an occlusive cuff that encloses an inflatable rubber bladder, and a pressure bult with a release valve that inflates the bladder manually

• Sizes vary —> make sure you have correct size for your patient; innacurate size produces inaccurate BP

Common Errors:

• Cuff too wide: false low

• Cuff to narrow / short: false high

• Cuff to loose: false high

Systolic Pressure

Occurs when the ventricles of the heart contract and force blood under high pressure into the aorta

Tachycardia

An abnormally elevated rate, above 100 BPM in adults

Thermogenesis

The process of heat generation by living organisms to maintain body temperature

Thermoregulation

The process by which organisms, including humans, maintain a stable internal body temperature, typically between 36.5 - 37.5C, to ensure proper enzyme function and overall health

• homeostatic mechanism

Vital Signs

Provide data to determine a patient’s usual or baseline state of health.

• Important to clinical care and should never be neglected

• Promotes safety and alerts health care providers to real-time changes in patient status

Apnea

The cessation of breathing

Cardiac Output

Amount of blood ejected from the left ventricle each minutes

• Normal: 4-8 L / min in the healthy adult at rest

Cheyne-Stokes Respiration

Occurs when there is decreased blood flow or injury to the brainstem. Type of breathing is an abnormal respiratory pattern, with periods of apnea followed by periods of deep breathing and then shallow breathing followed by more apnea.

Diaphragmatic Breathing

Useful for patients with pulmonary disease and dyspnea. Type of breathing increased tidal volume and respiratory rate, which leads to an overally improved breathing pattern and quality of life.

• Requires patient to relax intercostal and accessory respiratory muscles while taking deep inspirations

Diffusion

Responsible for moving th erespiratory gases from one area to another by concentration gradients

Hemoptysis

• Coughing up of blood or blood tinged sputum from the lungs or lower respiratory tract

• Indicates a serious medical condition

Humidification

The process of adding water to gas to keep airways moist.

• Necessary for patients receiving oxygen therapy at high flow rates (greater than 4L/minute)

• Bubbles oxygen through STERILE water

Hyperventilation

A state of ventilation in which the lungs remove carbon dioxide faster than it is produced by cellular metabolism

• Severe anxiety, infection, drugs, or an acid-base imbalance can induce this

Hypoventilation

Occurs when alveolar ventilation is inadequate to meet the oxygen demand of the body or to eliminate sufficient carbon dioxide

• body retain carbon dixoide

• Caused by: atelectasis, COPD patients receiving excess oxygen

Hypoxia

Inadequate tissue oxygenation at the cellular level. Results from a deficiency in oxygen delivery or oxygen use at the cellular level.

• Life threatening condition, can cause cardiac dysrhythmias

• Causes: decreased hemoglobin level / lowered oxygen-carrying capacity of the blood, diminished concentration of inspired oxygen (high altitudes), inability of tissues to extract oxygen from the blood, decreased difussion of oxygen from alveoli to the blood, poor tissue perfusion, impaired ventilation

• Signs: restlessness, decreased LOC, dizziness, behavioral changes, elevated BP, elevated pulse rate, elevated rate and depth of respiration

Incentive Spirometry

Encourages voluntary deep breathing by providing visual feedback to patients about inspiratory volume

• Common intervention that promotes deep breathing and is thought to treat / prevent atelectasis

• Often used with postoperative patients

• 10 times per hour, every hour

Kussmaul Respiration

Increased in rate (greater than 35 breaths / min) and depth of respirations

• compensate fro severe metabolic acidosis

Myocardial Infarction (MI)

• Heart Attack, acute coronary syndrome (ACS)

• Results from sudden decreases in coronary blood flow or an increase in myocardial oxygen demand without adequate coronary perfusion

• Cellular death occurs after 20 minutes of myocardial ischemia

• Men: crushing, squeezing or stabbing chest pain, often in left chest and sternal area, may be in back, radiates down the left arm, jaw, teeth, epigastirc area

• Women: angina, fatigue, indigestion, shortness of breath, and back or jaw pain

  • Increased risk of heart disease as they get older

  • Leading cause of death in women in the US

  • On average have greater blood cholesterole, and triclyeride levels and are more obese

  • Twice the risk of dying within the first year after a heart attack than men

,

Nasal Cannula

A device that gives you supplmental oxygen through your nose

• a thin flexible tube that hoes around your head and has two prongs that are placed in the nostrils

• 20-44% oxygen delivered

Nebulization

Adds moisture to inspired air by mixing particles of varying sizes with the air.

• enhances mucociliary clearnance

Also a method of administration for certain medications such as bronchodilators and mucolytic agents for patients with conditions like asthma

Orthopnea

Abnormal condition in which a patient has difficulty breahing when lying flat that is relieved by sitting up or standing up

• symtom not a disease itself

• often caused by heart failure, or COPD

• use pillows to prop patient up until they feel they can breathe properly

Perfusion

Relates to the ability of the cardiovascular system to pump oxygenated blood to the tissues and return deoxygenated blood to the lungs

Postural Drainage

Component of pulmonary hygiene; it consists of drainage, positioning, and turning and is sometimes accompanied by chest percussion and virbrations

• aids in improving secretion clearance and oxygenation

Pursed Lip Breathing

Involves deep inspiration and prolonged expiration through pursed lips to prevent alveolar collapse

• improve exercise tolerance, breathing pattern and arterial oxygen saturation in patients with COPD

Stroke Volume

the volume of blood ejected from the ventricles during systole

Ventilation

Process of moving gases into and out of the lungs with air flowing into the lungs during inhalation (inspiration) and out of the lungs during exhalation (expiration)

• requires coordination of the muscular and elastic properties of the lungs and thorax

Ventilator-Associated Pneumonia

A common healthcare associated infection (HAI) in the ICU

• associated with increased hospital lenght of stay, increased moratality, increased psychological cost, and increased hospital costs (40,000 extra per hospital stay)

• Pneumonia that develops greater than 48 hours after insertion of artificial airway or initiation of mechanical ventilation