Oxygenation

Oxygen

• Most basic need according to Maslow. Death occurs within a few minutes of being deprived of oxygen.

• Oxygenation of our system requires proper function of both respiratory & cardiovascular systems.

• Respiratory system –gas exchange O2 & CO2; Cardiovascular system –responsible for transport of these gases throughout our system to all body tissues.

Respiratory system structures & functions

• Airways

– Nose & pharynx,

– Trachea

– Bronchi, Rt & Lt; Bronchioles

– Alveolar ducts & sacs

• Pleural space

• Muscles of respiration

– Diaphragm; intercostals

– Accessory; abdominal

• Upper airways- passageways, warm & humidify air.

• Alveoli-exchange of gases; O2/CO2

• With each normal breath in adult about 500 ml air move.

Cardiovascular structures & functions

• Atria, rt & lt

• Ventricles, rt & lt;Valves

• Aorta; coronary arteries

• Cardiac tissue layers-endocardium, myocardium, epicardium, pericardium

• Electrical system-SA node, AV node, Bundle of HIS, Bundle Branches,Purkenjie Fibers

• Blood transports oxygen from lungs to cells throughout the body and returns CO2 to be excreted from body

Assessing Oxygenation

• History: ask about- diseases/illnesses-chronic respiratory/heart problems; SOB; dyspnea; wheezing, cough; fatigue, activity level, chest/other pain, meds; smoking history

• Exam-respiratory rate, rhythm, pattern, depth, effort (WOB); Heart rate, rhythm, pulses; cap refill; Bp; Lung sounds; Skin color-central, peripheral (also temp), mucous membranes, nailbeds; Level of Consciousness

Diagnostic Tests

• ABGs

– Ph—7.35-7.45

– pO2—80-100

– pCO2—35-45

– HCO3—22-26

– SaO2—95-100%

• Arterial stick; hold pressure 5 minutes

• Pulse oximetry-non-invasive method to indirectly measure O2 saturation of blood. Probe on finger; no nail polish, no artificial nails—SpO2—95-100%

Common signs of inadequate oxygenation

• Hypoxemia-inadequate oxygenation of the blood

• Hypoxia-inadequate oxygen to tissues

• S&S: Early: restlessness, agitation, mental dullness, confusion;

• Initially: Increased Bp, P, R; dyspnea; cardiac dysrhythmias

• Later: accessory muscle use, nasal flaring; stupor; stridor.

• Latest: Cyanosis Chronic: Clubbing of fingers

Promoting Oxygenation
Nursing Strategies

• Clearing Respiratory Secretions

– Cough-effective cough helps clear lower airways of secretions—deep breathing and coughing exercises. Splinting painful areas while coughing helps.

– Suctioning- done by nurse to clear airways when pt is unable to clear own.

Enhancing gas exchange

• Positioning—

– Fowler’s position-moves abdominal organs away from diaphragm

– Orthopneic or tripod position—sitting up; arms on pillows or overbed table.

– Postural drainage—different positions used to drain different lobes of lungs

Enhancing gas exchange

• Breathing exercises:

• Deep breathing- maximizes ventilations; re-inflates alveoli. Incentive spirometry encourages deep breathing.

• Pursed-lip breathing-technique that prolongs expiration. Useful for pts with COPDs (eg. Emphysema) and for slowing respirations with anxiety

Enhancing gas exchange

• Mobilizing secretions:

– Hydrating pt—force fluids—will help liquefy secretions; easier to cough up

– Humidification of air—helps liquefy secretions

• Maintain open airway:

– Remove any obstructions

– Artificial airways

• Space activities and provide rest periods between ADLs and exercise.

– Assess for activity intolerance

Enhancing Oxygenation
O2 therapy to treat hypoxemia

• Requires MD order. Treat as if a drug. Amount, method of delivery, duration. Ex- O2 @ 2L/min per NC continuously. LPN monitors & cares for pts with O2.

• Expensive, serious side effects, safety risks

– Safety precautions—O2 supports combustion; no sparks, no flames, no smoking. No acetone products, no hair sprays, no petroleum products

O2 therapy

• Side effects:

– O2 Toxicity--Lung damage may occur with high concentration (>50%) over extended time (>2-3 days). --non-productive cough, chest pain, headache

– Hypoxia– monitor for signs & symptoms ; cardiac dysrhythmias

O2 delivery devices

• Nasal Cannula (NC)- hollow tube with prongs that are placed in nose. For lower concentrations. OK if prongs near nose. Caution: monitor cheeks & ears for skin breakdown

• Masks- variety-type MD order. Mask always humidified. May make dyspneic pt feel smothering. Monitor skin for maceration. Dry skin periodically. Check for breakdown.