1. Stressors that Affect Oxygen Needs
NUR101 FALL 2008
K. BURGER, MSEd, MSN, RN, CNE
LECTURE #19
PPP by Sharon Niggemeier RN, MSN
Revised October 2005 by K. Burger

2. Oxygenation Ventilation- air moves in & out of lungs
External respiration-exchange of O2 & CO2 between alveoli and blood
Gas Transport- blood transports O2 & CO2 to body cells
Internal respiration- exchange of O2 & CO2 between blood and cells.
Internal- exchange of O2 and CO2

3. Checkpoint
T / F The pulmonary artery carries oxygenated blood away from the lungs.
The pulmonary ARTERY carries un-oxygenated blood from the heart
(R Ventricle) to the lungs
The pulmonary VEIN carries oxygenated blood away from the lungs
WHERE does it go????
L Atrium and L Ventricle and then AORTA to body
FALSE

4. Factors Affecting Respiration
Integrity of the airway system (ventilation)
Functioning cardiovascular system (perfusion)
Functioning alveoli (diffusion)
Functioning medulla & chemoreceptors
Ventilation- Physical movement of gases into and out of lungs
Perfusion- passage of blood through the pulmonary circulation. Amount of blood flowing thru lungs effects amount of O2 & CO2 exchanged.
Diffusion- passage of gases thru the resp. membrane from the alveolar sac to the capillaries and back.
Medulla- brain stem: stimulated by Inc. CO2 will cause an inc. ht. Rate to blow off CO2 and this inc. O2 levels
Chemoreceptors- sensitive to inc. CO2 in arterial blood gas level activates medulla.

5. Pulmonary Ventilation
Inspiration- air flows into lungs
Expiration-gases flow out of lungs According to pressure gradiant – Boyle
Intrapulmonic or intra-alveolar pressure- pressure within alveoli (fluctuates: Inspiration 759mm Hg Expiration 761mm Hg)
Intrapleural pressure-pressure within the intrapleural space (always negative) (756 mm Hg)
Note: Atmospheric Pressure = 760 mm Hg
Respiration depends on volume changes within the thoracic cavity.
A change in the volume of air leads to a change in the air pressure, since gases always flow along a pressure gradient , a change in pressure results gases flowing into or out of lungs to equalize pressure.
BOYLES LAW – volume of gas at a constant temperature varies inversely with the pressure FLOW from higher pressure to lower pressure
INSPIRATION – diaphragm (aided by accessory external intercostal muscles) contracts, pulling downward ABOUT 3-5 CM lengthening thoracic cavity – creates negative intra-alveolar pressure
EXPIRATION – diaphragm relaxes, decreasing thoracic volume- creates positive intra-alveolar pressure ( greater than atmospheric air 760 mm Hg)
INTRAPULMONIC OR INTRA ALVEOLAR PRESSURE – fluctuates with respiration Inspiration = 759 mm Hg, Expiration = 761 mm Hg
INTRAPLEURAL PRESSURE – pressure in the space between 2 pleural linings. ALWAYS negative 756 mm Hg
Exerts pulling pressure on alveoli to keep them inflated. TERMED a transmural pressure gradient
PLEURISY = inflammation of pleural linings causes friction and pain. Fluid accumulation can decrease pressure resulting in reduced alveoli expansion

6. Factors Affecting Ventilation
Lung elasticity / compliance (ability to stretch and recoil)
Airway obstruction
Musculature condition
Neurological controls
ELASTICITY – TWO ELEMENTS: Elastic Recoil- ability of lungs to return to normal after stretching
Compliance – how difficult it is to stretch the lungs
Decreased RECOIL = Especially in EMPHYSEMA; difficulty fully expiring air
Decreased COMPLIANCE = normal aging and/or pulmonary fibrosis
OBSTRUCTION – narrowing of airways NOTE: chronic obstruction ADDS to decreased recoil
COPD Chronic Brochitis/ long-term inflammation leads to edematous linings and excessive mucous production
Asthma/ thickening of airways and/or constriction of airways from histamine induced edema
Emphysema / collapse of smaller airways and alveoli d/t destructive trypsin enzymes released by
macrophages as defense mechanism in response to chronic inhaled cigarette smoke
MUSCULATURE CONDITION
Respiration controlled by medulla with messages sent to diaphragm.
When respiratory center is depressed – decreased messages to diaphragm to contract
If diaphragm or supplying nerve network is damaged – no contraction
If overall condition of patient is extremely debilitated – decrease accessory muscle use

7. Checkpoint What is the name of the nerve that supplies the diaphragm?
PHRENIC NERVE

8. Alveoli Gas Exchange Air reaches alveoli
Oxygen from alveoli space moves into pulmonary capillary (oxygen uptake) via diffusion
Oxygen diffuses across alveoli membranes moving from high concentration (alveoli) to lower concentration (pulmonary capillary)
Partial Pressure Gradiants
Partial pressure = individual pressure exerted by a particular gas in a mixture of gases
Atmospheric Air 760 mm Hg
02 = 160 mm Hg ….. 21%
N2 Nitrogen = 600 mm Hg….79%
Arterial Blood PO2 = 100 mm Hg PCO2 = 40 mm Hg
Represented by Pgas Ex: PO2

9. Alveoli Gas Exchange
Surfactant- secreted by alveoli cells, keeps surfaces moist and prevents atelectasis
Atelectasis- incomplete lung expansion or collapse of alveoli
Lung Compliance- elasticity of lung tissue and flexibility of rib cage
Lung recoil- ability of lungs to recoil
Surfactant – A mixture of lipids and proteins secreted by Type II alveolar cells
Interspersed among the water molecules in the liquid film that surrounds each alveoli
Water molecules great greater surface tension – keeps alveoli stretched and maintains recoil
Surfactant creates reduced surface tension:
increases pulmonary compliance – reducing the work of inflation
reduces the lungs tendency to recoil – alveoli do not collapse as readily
Newborn respiratory distress syndrome – premature birth, not enough surfactant, greater effort to inspire
Also adjacent alveoli exert outward pressure on each other – aiding the maintenance of inflation
Lung compliance – normally very compliant and it takes less than 3% of our total energy expenditure to maintain quiet breathing
In lung disease energy may be as high as 30%
Recoil- lungs recoil after being stretched. In COPD there is decreased lung recoil leading to impaired respirations.

10. Other Factors Affecting Gas Exchange
Surface area
Thickness of tissue
Fick’s Law of Diffusion: Rate of a diffusion of gas is dependent on surface area and thickness of the membrane
FICKS Laws of diffusion
Rate of a gas through a sheet of tissue depends on surface area and thickness of the membrane
During heavy exercise and increased cardiac output many previously closed pulmonary capillaries are forced open.
This increases the surface area of blood available for exchange
Increased thickness can occur with pulmonary edema – buildup of excess interstitial fluid
pneumonia – buildup of excess mucous and fluid

11. Perfusion Transport of O2 & CO2 via blood to tissue
Volume of blood flowing through lungs affects amount of oxygen and gases exchanged
Adequate blood supply and cardiovascular functioning are needed
Oxyhemoglobin HbO2 (or SaO2)
Need the circulatory system to assist respiratory processes
Perfusion is dependent on having enough blood and functioning circulatory system to do the exchange
Oxygen is poorly soluble in body fluids so it must be bound to hemoglobin for transport.
The PO2 of the blood is not a measure of the total content of oxygen in the blood but only the dissolved portion
Only 1.5% of oxygen is dissolved in blood
Remaining 98.5 % carried on hemoglobin as Oxyhemoglobin HbO2 or SaO2
Inversely proportional
ANEMIC HYPOXIA – reduced O2 carrying capacity
CIRCULATORY HYPOXIA – blockage or shock
HYPOXIC HYPOXIA – reduced atmospheric O2 ( high altitudes, suffocation)
HISTOTOXIC HYPOXIA – HbO2 is OK but cells cannot use the oxygen supplied to them (cyanide poisoning)

12. Checkpoint
The majority of CARBON DIOXIDE molecules are transported in the blood as:
???
BICARBONATE
HCO3
60% = HCO3
30% on hemoglobin
10% dissolved in blood

13. Perfusion Rate of O2 transport depends on: Cardiac output
Activity level
CO2 transport
Cardiac output- Stroke volume x heart rate= 5L/min of blood needed to circulate
FACTORS THAT PROMOTE THE UNLOADING OF O2 FROM HEMOGLOBIN during increased cardiac output
Exercise ( increased cardiac output) produces:
Heat - metabolizing cell gives off heat and enhances O2 release from Hb
Increased CO2 in the blood ( attaches to hemoglobin and decreases O2 affinity) aids unloading of O2
Increased acid in blood does same thing as CO2

14. Neurologic/Chemical Controls of Respiration
Peripheral Chemoreceptors
Central Chemoreceptors
Medullary respiratory center
Spinal cord
Phrenic nerve
Diaphragm
Peripheral chemoreceptors located in CAROTIDs and AORTIC ARCH
Sense the PCO2 levels in blood
HYPERCAPNIA = increased CO2 levels in blood
Central chemoreceptors located in medulla close to the respiratory center
Increased CO2 in the blood cause release of H
The central chemoreceptors then….
Sense the H concentration in brain extracellular fluid (NOT the CO2 level) to trigger respiration

15. Factors Affecting Oxygenation
Environment
Emotions
Exercise
Health
Age
Life style
Medications
Respiratory History
Environment- work place, air pollution, smoke, clean chimneys, Sandblasting, Toxic fumes
Emotions- upset trigger attack asthma/ stress cause dyspnea which increases stress…
Exercise uses more O2, if resp. system not functioning to capacity increased exercise will cause inability to get enough O2
Health- Fluid overload ( renal and cardiac patients), severe and chronic illness-muscle wasting, anemia,
skeletal abnormalities ( kyphosis, pectus carinatum, pectus excavatum, scoliosis ) and of course Respiratory Disorders
Lifestyle- smokers/ second hand smoke.
Medications- Depressant effect of narcotics FYI O2 is considered a medication – need MD order
Age – premature infant ( lack of surfactant) VERSUS elderly ( loss of lung tissue elasticity, decreased muscle tone)

16. Checkpoint What is the normal respiratory rate of a newborn?
30-60 breaths/min
Vital Signs lecture notes SAY 40-60
Average adult = 16-20
They go down as we age

17. Assessing Respiratory Functioning
Difficulty breathing?
SOB?
Chest pain?
Coughing? Sputum production?
Nocturnal diaphoresis
Fatigue
Sleep with 2 or more pillows?

18. Assessing Respiratory Functioning
Respiratory Hx includes:
Allergies
Medications
Medical Hx
Smoking
Lifestyle / Activity Level
Stressors
Recent exposures
Developmental level
Allergies to cats/ dogs/ meds/food environment
Meds- take to tx resp problems…inhalers/ cough suppressant/ decongestant
Hx- asthma, TB, bronchitis, lung Ca COPD Cardio vascular disorders/ chronic illnesses
Smoking PPD?
Lifestyle-active, couch potatoes, can climb stairs without being SOB?
Stress –what brings on stress….effects breathing…Take a deep breath….i.e. at the dentist “breathe”
Exposure post 9/11 air particles/ Iraq sand/dust
Fireplace foe 2 weeks at the ski lodge
Dev.- infants prone to specific resp problems differ from elderly COPD

19. Assessing Respiratory Functioning
Patient states difficulty breathing: you can assess by using PQRST
P- provokes
Q- quality
R- region/radiation
S- severity scale
T- timing
P- when I’m near the cat
Q- I get SOB and wheeze
R-Tightness in my upper chest
S-7-8 on scale of 1-10 (worse)
T- it lasts till I take my inhaler

20. Assessing Respiratory Functioning
Respiratory Rate:
Tachypnea R>24
Bradypnea R<10
Apnea
Respiratory Depth:
Deep - diaphragmatic
Shallow
normal easy respirations 12-20
Tachy = respirations greater than 24/min rapid and shallow
FYI: Hyperventilation = increase in both rate and depth ( extreme exertion or anxiety )
_ Brady = respirations of 10 or less/min decreased but regular
FYI: Hypoventilation = decrease in both rate and depth ( shallower than brady ) = overdose of narcotics
Apnea – no respirations

21. Assessing Respiratory Functioning
Respiratory Rhythm:
Regular – “even and symmetrical”
Cheyne-Stokes
Kussmauls
Biot’s (ataxic – without rhythm)
Apneustic breathing (gasping)
Normal even and unlabored
C/S= shallow then increases then decrease and stop then shallow… related to decreased neuro response to CO2
K- deep rapid – metabolic Acidosis
B – like Cheyne stokes except regular rhythm interspersed with periods of apnea Also called ATAXIC
A- sustained inspiration effort with strained expiration – gasping

22. Assessing Respiratory Functioning
Respiratory Quality:
No difficulty- Eupneic/ Unlabored
Dyspnea
Orthopnea
Retractions
Use of accessory muscles
Auscultation:
Vesicular
Bronchial
Bronchovesicular
D- difficulty
O- leaning forward support by overbed table, tripod position
R intercostals muscles between ribs pull in
Accessory muscles = abdominal, scalene, sternocleidomastoid, trapezius, pectoralis
Vesicular- heard over most of lung field I>E
Bronchial- heard over trachea and larynx I<E
Broncovesicular Bronchi I=E

23. Assessing Respiratory Functioning
Adventitious Sounds:
Crackles: fine,medium,coarse
Wheeze: sibilant,sonorous
Stridor
Stertor
Pleural friction rub
Cough:
Nonproductive
Productive
Sputum
Hemoptysis
ADVENTITIOUS SOUNDS AUDIBLE VS AUSCULATATED
Sputum
Yellow/Green = bacterial infection may also be blood streaked
Mucoid = viral infection
Slight but persistant blood streaking = carcinoma
Larger amts of blood and purulence = TB
Fine crackles (hairs between fingers)- end of inspiration/ not cleared by coughing
Medium crackles – lower and moister sounding midstage of inspiration/ not cleared by coughing
Course crackles – loud and bubbly, during inspiration/ not cleared by coughing
Wheeze Sibilant = squeaky on inspiration and expiration/ louder on expiration
Sonorous ( Rhonchi) = snore like on inspiration and expiration / may clear with cough
Stridor- high pitched sound croup = acute airway obstruction
Stertor- snoring noise
Pleural Friction Rub = dry, grating/ inflammation of pleura/ inspiration and/or expiration/ heard laterally
Breath sounds

24. Respiratory Assessment Review
Oxygen delivery method correctly applied
Obtain a pulse oximetry reading (norm is >95%)
Check Vital Signs ?T ?P ?R
Auscultate the pt’s lungs
Note changes in skin and mucosa color
Assess capillary refill

25. Checkpoint
What are some other elements of a respiratory assessment not yet mentioned?
Neurological state
Color
+ tactile fremitus
Voice sounds
Decreased diaphragmatic excursion
Nail clubbing
AP vs Transverse Diameter
Barrel Chest?

26. Assessing Respiratory Functioning
Diagnostic tests:
Sputum
Nose/throat cultures
CBC (complete blood count)
ABG (arterial blood gases)
CXR (chest x ray)
PFT (pulmonary function tests)
Pulse Oximetry
Other: Scopes, CT, MRI, PET
SPUTUM- cells expelled from the lungs tested for: Cytology OR Culture
Best obtained in AM, no saliva, Sterile cup with cytology liquid ( 50% alcohol)
Nose/Throat Cultures- determine if pathogen is present & antimicrobial that it is sensitive to to destroy it: Strep/MRSA
CBC- determines RBC/ Hbg etc effects oxygenation
ABG: provide physiological functioning of respirations…
PaO2-partial pressure of O2 in arterial blood. Decreased levels indicate insufficient Norm = 100mmHg PaCO2 partial pressure of CO2 Norm = 40 mm Hg
CxR- lungs examined via x-ray
PFT- measures volume of air in lungs used to Dx and Tx & monitor resp system/ inspiratory and expiratory volumes
Pulse Ox- light waves measure noninvasive . SaO2 % or Sp02 = saturated O2 on Hgb in arterial blood % Less than 85 severe hypoxia
Based on the red and infrared light absorption characteristics of oxygenated and deoxygenated hemoglobin. Oxygenated hemoglobin absorbs more infrared light and allows more red light to pass through.
Deoxygenated (or reduced) hemoglobin absorbs more red light and allows more infrared light to pass through.
Caution with anemic patient – lo Hgb but all saturated CLICK ON WEBSITE
Bronchoscopy- scope used to visualize inside the lungs. Direct visualization
CT/MRI/PET –scans imaging used to Dx resp. disorders/pathology Indirect visualization

27. Alterations:Respiratory Functioning
Hypoxia
Hypoxemia
Hyperventilation
Hypercapnia
Obstructed airway
Foreign body obstruction (FBO)
Hypoxia- prolonged oxygen deprivation
Hypoxemia- decreased blood oxygen concentration
Hypervet- deep rapid respirations
Hypercapnia- CO2 retention
O/A- airway partially blocked diminished airflow, tongue/ edema/
FBO- meat/ toys/ coins food

28. Nursing Interventions Independent
Airway maintenance
Positioning
Deep breathing & coughing
Pursed-lip breathing
Abdominal/diaphragmatic breathing
Hydration
Teaching of health habits
ABC’s always maintain open airway to promote oxygenation… Hyperextension of neck ( unless otherwise contraindicated)
Artificial airway if necessary:
Oropharangeal keeps tongue from obstructing airway – post op
Nasopharangeal- used for frequent suctioning without nares trauma
Endotracheal-inserted via nose or mouth into trachea
Tracheostomy- surgical procedure to open airway via trachea
Positioning- allow for increased expansion of thoracic cavity…high fowlers/ orthopneic
DB&C raises sputum to maintain airway ..take deep breath thru the nose ( warms /filters air) and cough with force…may have to splint abd…. DB done alone to increase more efficient respirations
Pursed-lip- slowly inhale thru the nose exhale thru lips close together. This maintains positive pressure in lungs, prevents atelectasis and promotes fuller exhalation phase
A/D breathing- helps decrease resp. rate and increase volume. Place hands on abd/diaphragm, inhale slowly thru nose , inflating abd. As much as possible, exhale thru pursed lips while hands press on abd.
Hydration- need fluids to thin secretions so they are more easily expelled.
Habits- Teaching life style changes, no smoking, control asthma, monitor environment.etc..

29. Nursing Interventions Collaborative/Dependent
Incentive spirometry
Percussion/postural drainage
Suctioning
Oxygen therapy
Medications
I/S-allows for sustained maximum inspiration. More air in greater the oxygenation. Exhale, insert mouthpiece, inhale deeply to make ball rise in chamber, remove mouth piece exhale thru pursed lips.
Perc/PD- promotes drainage of secretions, Perc.- cupped hands beat firmly on chest. PD –Place client in various positions to promote lung drainage ( also known as chest physiotherapy.) Most often performed by Resp Therapy
Suctioning- clears secretions from airway. Using a device secretions are removed . Catheter placed in mouth, nose or lungs and secretions are sucked out.
PLEASE REVIEW THE PROCEDURAL OUTLINE ( OROPHARYNGEAL/NASOPHARYNGEAL SUCTIONING, ADMINISTERING OXYGEN) IN YOUR TEXTBOOKS PRIOR TO LAB SESSION
OT –provides supplemental oxygen (will discuss further)
Meds- various meds can assist pt. To breath easier thereby increasing their oxygenation (will discuss further)
IE: bronchodilators, antihistamines, mucolytics, corticosteroids

30. Nursing Interventions Collaborative/Dependent
Oxygen Therapy
Indications
Sources- wall outlet or portable tank
Monitor pulse oximetry
Methods- cannula, mask, venturi mask, tent/isolette,BiPAP, CPAP
Will discuss in lab.
Sources- wall outlet, or portable tank.
O2 is released under pressure and a regulator is needed to achieve the desired amount of O2
Measured in L/min or % depending upon the type of delivery system. Often attached to humidification
Methods-
LOW FLOW – provides only part of the patients total inspired air
Nasal Cannula- convenient/pt can talk and eat/causes nares to dry ( 2-3L )
Simple Mask – short time period ( 12 hrs or less ) / higher delivery ( must be 5L or more to avoid CO2 retention)
Re-breathers– collects some of expired air increasing overall O2 delivery
HIGH FLOW- provides total inspired air and consistent oxygen delivery
Venturi – Large tube narrows as it enters the mask creating air to be sucked into side ports ( keep unobstructed). Delivers a more precise volume of O2
Mask problems: claustrophobic, moist air and skin breakdown
Tent- plastic tent / w/ children doesn’t provide accurate concentration.
CAUTION IN COPD PATIENTS!! Normally the stimulus to breathe is excessive CO2 levels in blood but in COPD the chemoreceptors become de-sensitized to the excess CO2 and these patients respond to HYPOXIA ( low O2 levels ) for stimulus to breathe. If O2 therapy is administered too high this stimulus is removed and pt may stop breathing. Usually no more than 2L

31. Administering Oxygen Therapy
Flow rate
Humidification
Hydration
Positioning
Safety precautions
Document
MD order required
O2 is a drug must be prescribed
Flow rate- prescribed by MD L/min or % ( % = the Fraction Inspired Oxygen or FiO2)
Humidification- keeps mucus membranes moist
Hydration is important because O2 is very drying to the mucus membranes, nares is using N/C, mouth masks
Positioning, using semi to high fowlers
Safety precautions discuss next.
Document in nurses note or flow sheet, pt. Respiratory status, amount O2/min , how administered, any problems,

32. Oxygen Safety Precautions
Signs: “No smoking. Oxygen in use.”
 Remove matches, lighters and cigarettes.
 Remove and store electrical equipment to avoid sparks. Ground electrical equipment.
 Avoid materials that generate static electricity
 Avoid use of volatile, flammable materials, such as alcohol.
Know location & use of fire extinguishers & alarms.

33. Nursing Interventions
Medications
Nebulizer Tx
Cough suppressants
Mucolytic: expectorants
Bronchodilators
Corticosteroids
Tx- apparatus produces fines spray/mist of medications administered directly into the lungs bronchodilators open the airway to provide better oxygenation
Cough suppressants- stops coughs can be liquids/ lozenges/drops/ etc. Coughing can prevent pt. From sleeping, can cause further respiratory distress
Expectorants- thin secretions making it easier to expel
Bronchodilators- open narrow passage ways
Corticosteroids – reduce inflammation

34. Documentation Routine Nurses Note
Date
Time
LOC
Rate
Depth
Rhythm
Breath sounds (auscultated)
Quality
Color
1/5/05 10:23pm A & O x 3 Respirations 14 deep,even & unlabored, vesicular breath sounds clear, bilaterally, no cyanosis.

35. Nursing Diagnosis Ineffective airway clearance Risk for aspiration
Ineffective breathing pattern
Impaired gas exchange
Risk for suffocation
Ineffective tissue perfusion; cardiopulmonary
Impaired spontaneous ventilation
Dysfunctional ventilatory weaning response

36. Ineffective airway clearance
Checkpoint
Select a priority nursing diagnosis for the following scenario:
88 y.o. female with pneumonia who has a non-productive cough, R= 24, course crackles upon auscultation. She is weak, undernourished and fatigued.
Ineffective airway clearance

37. Checkpoint
Select a priority nursing diagnosis for the following scenario:
A patient with hx of emphysema with decreased PO2, increased CO2 levels who is dyspneic and restless.
Impaired Gas Exchange

38. Ineffective Tissue Perfusion; Cardiopulmonary
Checkpoint
Select a priority nursing diagnosis for the following scenario:
A patient admitted to the ER post MVA with notable blood loss, BP= 80/50, P=120, R=22
Ineffective Tissue Perfusion; Cardiopulmonary

39. Summary: Oxygenation
Oxygenation based on ventilation/perfusion/diffusion of oxygen
Various factors effect oxygenation
Assessment includes respiratory Hx, clinical exam, diagnostic tests
Interventions include airway maintenance /proper breathing/ oxygen therapy/meds