Vital Signs, Oxygen, Chest Tubes, and Lines Practice Flashcards

Key Terms Definitional Guide

• Apnea: Cessation of spontaneous ventilation.

• Atelectasis: Absence of gas from part or the whole of the lungs as a result of failure of expansion or reabsorption of gas from the alveoli.

• Auscultation: Listening to sounds of the body, typically through the use of a stethoscope.

• Body Temperature: Measurement of the degree of heat of the deep tissues of the human body.

• Bradycardia: Slowness of the heartbeat as evidenced by slowing of the pulse rate to less than $60 \text{ beats per minute (BPM)}$.

• Bradypnea: Abnormal slowness of breathing.

• Diaphoresis: Profuse sweating.

• Diastolic: Pertaining to dilation, or a period of relaxation of the heart, especially of the ventricles.

• Dyspnea: Difficult or labored breathing.

• Febrile: Pertaining to or characterized by fever.

• Homeostasis: Constancy in the internal environment of the body, naturally maintained by adaptive responses that promote healthy survival.

• Hypertension: Persistently high arterial blood pressure.

• Hyperthermia: Abnormally high body temperature, especially that induced for therapeutic purposes.

• Hypotension: Abnormally low blood pressure; seen in shock but not necessarily indicative of shock.

• Hypothermia: Low body temperature.

• Hypoxemia: Decreased oxygen tension (concentration) in the blood.

• Hypoxia: Reduction of oxygen supply to the tissue.

• Intubation: Insertion of a tubular device into a canal, hollow organ, or cavity.

• Orthopnea: Difficulty breathing except when sitting up or standing erect.

• Pleural Effusion: Increased amounts of fluid within the pleural cavity, usually the result of inflammation.

• Pneumothorax: Presence of air or gas in the pleural cavity.

• Pulse Oximeter: Photoelectric device used for determining the oxygen saturation of the blood.

• Respiration: Action of inhaling oxygen and exhaling carbon dioxide during breathing.

• Sphygmomanometer: Instrument for measuring blood pressure.

• Systolic: Pertaining to tightening, or a period of contraction of the heart (myocardium), especially that of the ventricles.

• Tachycardia: Rapidity of the heart action, usually defined as a heart rate greater than $100 \text{ BPM}$.

• Tachypnea: A rapid rate of breathing.

• Tidal Volume: Volume of air inhaled and exhaled during one respiratory cycle.

• Ventilation: Mechanical movement of air into and out of the lungs.

Vital Signs as Indicators of Homeostasis Status

• Concept of Homeostasis: As stated by Peter Latham, life is known as a complex of many functions and health as the integrity and harmony of these functions. Homeostasis is a relative constancy in the internal environment maintained by adaptive responses.

• Primary Mechanisms: The core adaptive mechanisms include:

  • Heartbeat

  • Blood Pressure

  • Body Temperature

  • Respiratory Rate

  • Electrolyte Balance

• Clinical Utility: Vital signs serve as objective, noninvasive evidence of a patient's immediate condition. They are physiological indicators of response to therapy and provide the first clues to adverse reactions from treatment or diagnostic procedures.

• Sensorium: Assessment of mental alertness is often reported alongside vital signs.

• Benchmarks: Recordings taken at the onset of procedures serve as critical benchmarks for the patient's initial status.

Body Temperature: Thermoregulation and Measurement

• Description: Reflects the heat of the body's deep tissues. Because humans are warm-blooded, cells function best within a narrow range.

• Normal Mean Temperature: Approximately $98.6 \, ^{\circ}\text{F}$ ($37 \, ^{\circ}\text{C}$), with a daily fluctuation of $1 \text{--} 2 \, ^{\circ}\text{F}$ ($0.5 \text{--} 1.0 \, ^{\circ}\text{C}$).

• Thermoregulation Mechanisms: Controlled by the hypothalamus.

  • Heat Dissipation: Initiates peripheral vasodilation and diaphoresis (sweating). The respiratory system also removes excess heat via ventilation.

  • Heat Preservation: Initiates shivering (to generate heat) and vasoconstriction (to conserve heat).

• Measurement Methods:

  • Electronic/Digital Thermometers: Most common; readings obtained in $20 \text{ seconds to } 3 \text{ minutes}$.

  • Mercury-filled Glass Bulbs: Seldom used in modern facilities due to toxic exposure risk. Oral bulbs are slender/pointed; rectal bulbs are rounded. Requires notifying the health department if a spill occurs.

• Routes of Measurement:

  1. Oral: Thermometer placed under the tongue. Range: $97.7 \, ^{\circ}\text{F} \text{--} 99.5 \, ^{\circ}\text{F}$ ($36.5 \, ^{\circ}\text{C} \text{--} 37.5 \, ^{\circ}\text{C}$).

  2. Axillary: Placed between the upper arm and torso. Notorious for inaccuracy; requires $5 \text{--} 10 \text{ minutes}$. Registers slightly lower than oral.

  3. Rectal: Lubricated bulb inserted into the anal opening for $2.5 \text{--} 5 \text{ minutes}$. Considered the most accurate reflection of core temperature. Registers approx. $1 \, ^{\circ}\text{F}$ higher than oral.

  4. Tympanic: Membrane thermometer placed in the ear; provides reading in $3 \text{ seconds}$. Range: $95.9 \, ^{\circ}\text{F} \text{--} 99.5 \, ^{\circ}\text{F}$ ($35.5 \, ^{\circ}\text{C} \text{--} 37.5 \, ^{\circ}\text{C}$).

  5. Temporal Artery (TA): Noninvasive swipe across the forehead/temporal region. Closely correlates to core temperature and registers approx. $1 \, ^{\circ}\text{F}$ higher than oral.

  6. Infrared Digital Thermometers: Used to detect superficial skin temperature variations for wound management or diabetic foot neuropathies; not useful for core temperature.

Significance of Temperature Abnormalities

• Hyperthermia (Fever/Febrile): Defined as oral temperature >99.5 \, ^{\circ}\text{F}.

  • Physiological Impact: Increases metabolic rate, resulting in increased oxygen consumption and $CO_2$ production. The cardiopulmonary system must work harder.

  • Causes: Viral/bacterial infections, postoperative healing responses ($1 \text{--} 2 \text{ days}$), myocardial infarction, or hypothalamus injury (CVA, edema, tumor).

  • Complications: Prolonged hyperthermia causes confusion, dizziness, and coma.

• Hypothermia: Below normal range.

  • Causes: Cold exposure, trauma to the hypothalamus.

  • Induced Hypothermia: Medically initiated during heart surgery to decrease metabolic and cardiopulmonary demands.

Respiratory Rate: Mechanics and Assessment

• Physiology of Respiration: Responsible for delivering $O_2$ from the environment to tissues and eliminating $CO_2$. Metabolic waste ($CO_2$) must be expelled to avoid death.

• Inspiration: The diaphragm (major muscle of ventilation) contracts and moves downward, expanding the chest cavity and decreasing internal pressure so air moves in.

• Expiration: The diaphragm relaxes and returns to its original position at the floor of the chest cavity, increasing pressure to push air out.

• Assessment Technique: Observed by the rise (inspiration) and fall (expiration) of the chest over $1 \text{ minute}$. Best performed without the patient's knowledge (e.g., keeping the hand on the wrist after taking the pulse).

• Normal Ranges:

  • Adult: $12 \text{--} 20 \text{ breaths/min}$.

  • Child (under 10): $20 \text{--} 30 \text{ breaths/min}$.

  • Newborn: $30 \text{--} 60 \text{ breaths/min}$.

• Clinical Observations: Includes rate, depth (shallow, normal, deep), and pattern (regular, irregular).

• Abnormalities:

  • Tachypnea: >20 \text{ breaths/min} (Adult). Causes: Exercise, fever, anxiety, pain, infection, heart failure, hypoxia.

  • Bradypnea: Decreased rate; occurs with drug overdose, head trauma, and hypothermia.

  • Dyspnea: Difficult breathing.

  • Orthopnea: Difficulty breathing unless sitting or standing.

  • Apnea: Absence of spontaneous ventilation; an ominous sign.

Pulse: Cardiovascular Monitoring

• Description: Reflects the rapidity of heart contractions to transport oxygenated blood and return deoxygenated blood.

• Measurement Sites:

  1. Radial Artery: Thumb side of the wrist.

  2. Brachial Artery: Antecubital fossa in adults; upper arm in infants.

  3. Carotid Artery: In the neck; standard site during CPR.

  4. Apical Pulse: Measured via auscultation (stethoscope) over the heart.

• Normal Pulse Rates:

  • Adult: $60 \text{--} 100 \text{ BPM}$.

  • Child (1--10 years): $70 \text{--} 120 \text{ BPM}$.

  • Newborn: $100 \text{--} 160 \text{ BPM}$.

• Monitoring Devices:

  • Electrocardiograph: Monitors electrical activity, heart rate, and rhythm via chest electrodes.

  • Arterial Line: Catheter inserted into an artery connected to a pressure transducer for continuous BP and HR monitoring.

  • Pulse Oximeter: Noninvasive probe for hemoglobin oxygen saturation ($SpO_2$) and pulse. Normal $SpO_2$: $95\% \text{--} 100\%$. Factors for inaccuracy: patient movement, poor peripheral perfusion, nail polish, acrylic nails.

• Abnormalities:

  • Tachycardia: Increase of >20 \text{ BPM} in resting adult or rate >100 \text{ BPM}. Causes: anemia, shock, CHF, hypoxemia, anxiety.

  • Bradycardia: Decreased heart rate; seen in athletes, hypothermia, or heart blocks. May lead to hypotension and syncope.

Blood Pressure: Measurement and Significance

• Description: The force exerted by blood on arterial walls.

  • Systolic Pressure: Peak pressure during heart contraction (ventricular ejection).

  • Diastolic Pressure: Constant pressure on vessels when the heart is relaxed.

• Measurement Equipment: Sphygmomanometer (mercury or aneroid types) and stethoscope.

• Assessment Procedure:

  1. Place cuff on upper arm midway between elbow and shoulder.

  2. Inflate cuff above systolic pressure to collapse the brachial artery.

  3. Slowly deflate; the first turbulent sound heard (Korotkoff sounds) is the systolic reading.

  4. When sound ceases, the value is the diastolic reading.

• Normal Range: Systolic <120 \, \text{mm Hg}; Diastolic <80 \, \text{mm Hg}.

• Hypertension Categories:

  • Prehypertension: Systolic $120 \text{--} 139 \, \text{mm Hg}$; Diastolic $80 \text{--} 89 \, \text{mm Hg}$.

  • Stage 1: Systolic $140 \text{--} 149 \, \text{mm Hg}$; Diastolic $90 \text{--} 99 \, \text{mm Hg}$.

  • Stage 2: Systolic $\ge 160 \, \text{mm Hg}$; Diastolic $\ge 100 \, \text{mm Hg}$.

• Hypotension: Defined as <95/60 \, \text{mm Hg}. Generally only problematic if symptomatic (dizziness, confusion). Seen in shock, sepsis, or internal bleeding.

Oxygen Therapy: Distribution and Clinical Indications

• Oxygen Logic: Essential for cellular metabolism. Absence causes brain damage in $6 \text{ minutes}$. Oxygen is a colorless, tasteless, odorless gas, constitutes $21\%$ of atmospheric gas, and supports combustion.

• Indications: Correction of hypoxemia or tissue hypoxia (inadequate $O_2$ at cellular level). Sensitive tissues: brain, heart, lungs, liver.

• Oxygen as a Drug: Defined by the Federal Food, Drug, and Cosmetic Act of 1962. Must be prescribed by a physician. Potential negative effects: absorptive atelectasis and oxygen toxicity.

• Bulk Distribution: Liquid oxygen stored in insulated stainless-steel containers; converted to gas by vaporizers acting as heat exchangers.

• Oxygen Cylinders: Green-colored (in the US). E-cylinders are common for transport. Regulators include a flowmeter ($L/min$) and pressure manometer (volume in tank).

• Oxygen-Conserving Devices:

  • Pulse Dose: Delivers fixed volume during inspiration via electronic circuit.

  • Demand Device: Delivers variable volume based on length of inspiration.

Oxygen Delivery Devices

• Low-Flow Systems (Variable Concentration): Do not meet entire inspiratory needs; room air is entrained.

  • Nasal Cannula: Short prongs in nares. Flows: $1 \text{--} 6 \, L/min$. $FiO_2$: $24\% \text{--} 40\%$. Humidifier added for flows >4 \, L/min.

  • Simple Oxygen Mask: Covers nose and mouth. Needs flow >6 \, L/min to prevent $CO_2$ accumulation. $FiO_2$: $35\% \text{--} 50\%$.

  • Partial Rebreathing Mask: Includes reservoir bag for first third of exhaled gas (anatomic deadspace). Flow: min $10 \, L/min$. $FiO_2$: $40\% \text{--} 70\%$.

  • Nonrebreathing Mask: One-way valves to prevent room air dilution. Flow: min $10 \, L/min$. $FiO_2$: $60\% \text{--} 80\%$.

• High-Flow Systems (Fixed/Precise Concentration): Meet/exceed inspiratory needs.

  • Large Volume Nebulizer: Generates aerosol mist. Filled with sterile water. Flow: at least $8 \, L/min$. $FiO_2$: $28\% \text{--} 100\%$.

  • Air-Entrainment (Venturi) Mask: Uses high-velocity source gas to entrain room air. Concentrations: $24\%$, $28\%$, $35\%$, $40\%$, and $50\%$.

  • High Flow Nasal Cannula (HFNC): Introduced in early 2000s. Uses blender. Flow: up to $60 \, L/min$. $FiO_2$: $21\% \text{--} 100\%$. Heated and humidified.

• Enclosures for Pediatrics:

  • Oxygen Tent: Covers child's bed; difficult to control concentration due to openings.

  • Oxyhood: Plastic box over infant's head. Flow: $\ge 7 \, L/min$. $FiO_2$: $21\% \text{--} 100\%$.

• Mechanical Ventilators: Deliver set respiratory rate, volume, and $FiO_2$. Care must be taken not to dislodge the artificial airway. Moisture in corrugated tubing must be cleared into drainage bags.

Chest Tubes and Lines: Endotracheal and Thoracostomy

• Endotracheal (ET) Tubes:

  • Indications: Mechanical ventilation, airway obstruction, aspiration risk, tracheobronchial lavage.

  • Placement: Distal tip should be $1 \text{--} 2 \text{ inches}$ ($3 \text{--} 5 \, \text{cm}$) above the carina.

  • Malpositioning: Most frequent error is intubation of the right main-stem bronchus (it has a shallower angle than the left), causing left lung atelectasis.

• Thoracostomy (Chest) Tubes:

  • Use: Drain intrapleural space and mediastinum of air or fluid.

  • Pleural Conditions:

    • Pneumothorax: Air in cavity. Insertion: $2\text{nd} \text{--} 3\text{rd}$ intercostal space at midclavicular line (air rises).

    • Hemothorax/Effusion: Fluid (blood/serum). Insertion: $5\text{th} \text{--} 6\text{th}$ intercostal space (fluid sinks with gravity).

  • Radiographic Evidence: Costophrenic blunting requires approx. $300 \, \text{mL}$ of fluid to see on PA/AP views, but only $150 \, \text{mL}$ on lateral decubitus views.

  • Tension Pneumothorax: Life-threatening; air enters but cannot escape, shifting the mediastinum. Requires immediate aspiration.

Central Venous and Pulmonary Arterial Lines

• Central Venous (CV) Lines: Catheters inserted into large veins for drugs, nutrition, or pressure monitoring.

  • Types: PICC (peripherally inserted), tunneled (Broviac, Hickman, Groshong), and implanted ports (Port-a-Cath).

  • Preferred Location: Superior vena cava (SVC), $2 \text{--} 3 \, \text{cm}$ above the right atrial junction.

  • Insertion Sites: Subclavian vein (most common), internal jugular, or femoral vein.

• Pulmonary Arterial (PA) / Swan-Ganz Catheters:

  • Purpose: Estimate left ventricular end-diastolic pressure by measuring PA-wedged pressure.

  • Mechanics: Distal balloon is inflated so the catheter floats and "wedges" in a small pulmonary artery branch momentarily.

  • Monitoring: Synchronized with cardiac monitor tracings; balloon is deflated after measurement to resume flow and prevent infarction.

• Recognition of Placement Errors:

  • Right-sided approach: Image should stay to the right of the vertebral column and not cross midline.

  • Left-sided approach: Must cross the midline horizontally (via left brachiocephalic vein) to reach the SVC. Failure to cross midline may indicate placement in the thoracic duct.

  • Complications: Catheter dislodgment, occlusion (clots/precipitates), pneumothorax, or hemothorax during insertion.