Oxygenation, Ventilation, and Respiration:

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Oxygenation, Ventilation, and Respiration

• Management of clients with critical alterations
  in respiratory function
• Carol Isaac MacKusick, MSN, RN, CNN
• Nursing 2904
• January 12 and January 24, 2006

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A Brief Review

• Review respiratory assessment from Nursing 2903
• Review basic alterations in respiratory function
  from Nursing 2903
• Lecture from Fall, 2005 on web site for reference
  if needed
• Terminology list
• Basic / advanced

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Pharmacology

• Should review and KNOW
• Bronchodilators
• Beta-adrenergic agonists
• Anti-inflammatory agents
• Glucorticoids
• Mast cell stabilizers
• Leukotriene modifiers
• Common cold agents
• Antitussives
• Expectorants
• Mucolytics

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Pharmacology

• Need to KNOW
• Medications that might induce respiratory
  depression
• Barbiturate
• Benzodiazepines
• Opioids
• Surfactant agents
• Anticoagulation agents
• TB agents
• Anti-infectives
• Vasodilators

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Physiology Review

• Respiration
• Process by which the bodys cells are supplied
  with oxygen and carbon dioxide is removed as
  waste
• Ventilation
• Mechanical movement of airflow to and from the
  atmosphere and the alveoli

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Compliance

• Ease with which the lungs are able to expand
• Determined in terms of lung volume and pressure
• CL DV (mL) / DP (cm H2O)
• Small / large balloons aveloli
• Normal CL 50-100mL V / 1 cm H2O P

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Compliance

• Decreased compliance stiff lungs
• More P needed to increase V
• Increases work of breathing
• Decreases tidal volume
• Things that affect
• Surfactant
• Reduction
• Pulmonary problems
• Restrictive disorders
• External / Internal

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Diffusion

• Movement high to low
• Four factors that affect alveolar diffusion
• Gradient
• Surface area
• Thickness
• Length of Exposure

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Ventilation (V) Perfusion (Q) Relationship

• Ratio of alveolar ventilation to pulmonary
  capillary perfusion
• Normal V/Q ratio 0.8
• Pulmonary capillary perfusion is gravity
  dependent
• Intrapulmonary shunting
• Airflow follows the path of least resistance
• Alveolar deadspace

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V/Q Ratio

• V/Q ratio gt 0.8 is dead space producing
• Decreased cardiac output, PE, pneumothorax
• V/Q ratio lt 0.8 is shunt producing
• Hypoventilation, obstructive and restrictive lung
  dxs
• With V/Q mismatch
• PAO2 and O2 saturation decrease
• Think positioning!!

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Shunting

• Pulmonary shunting major cause of hypoxemia
• Physiologic shunt No alveolar-capillary
  diffusion taking place
• Normal ranges from 2-5 of cardiac output
• gt 15 respiratory failure

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Oxyhemoglobin Dissociation Curve

• Handout for further information
• Graph of relationship between dissolved oxygen
  and hemoglobin bound oxygen
• Initial part of curve steep but flattens at the
  top
• Flat portion represents binding of oxygen to
  hemoglobin in the lungs

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Oxyhemoglobin Dissociation Curve

• Shifting
• Hemoglobin has a steady and predictable affinity
  for oxygen
• Shifts in position mean that there is a change in
  the way oxygen is taken up by the hemoglobin
  molecule at the alveolar level as well as a
  change in the way oxygen is delivered at the
  tissue level

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Assessment

• Review and know N2903 assessment information
• Know Urden, 214-217
• Review PFTs and implications
• Urden, 217-224
• SB, 482-490
• Review and know respiratory / acid base
  calculations
• Handouts for review
• To be covered in seminar in detail

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Restrictive Pulmonary Disorders

• Problems with inflow of air
• Decreased lung compliance -gt decreased lung
  expansion
• Problem with volume not airflow
• Total lung capacity is decreased
• Includes
• External
• Obesity, chest burns, flail chest, NM dx
• Internal
• Pneumonia, atelectasis, CHF, pulm edema,
  fibrosis, tumors, pneumothorax

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Restrictive Assessment

• Common signs and symptoms
• Increased respiratory rate
• Decreased tidal volume
• Normal to decreased PaO2
• SOB
• Cough
• CP or discomfort
• Fatigue
• Weight loss

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Obstructive Pulmonary Disorders

• COPD
• Air able to flow into lungs but becomes trapped,
  making it difficult to rid the lungs of inspired
  air
• Increased expiration time so lungs may never be
  empty before time to inhale again
• Frequently associated with increased lung
  compliance accompanied by loss of lung recoil

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COPD

• Chronic bronchitis V/Q ratio decreased
• Emphysema V/Q ratio R/T both ventilation and
  perfusion are equally destroyed

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Obstructive Assessment

• Common signs and symptoms
• Mucus
• Wheezes, rhonchi
• Dyspnea
• Diminished breath / heart sounds
• Barrel chest
• Hypercapnia / respiratory acidosis
• Hypoxemia
• Cor pulmonale
• Accessory muscle use
• E gt I
• nL to increased TLC
• Increased FRC
• Decreased FEV and VC

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Cor Pulmonale

• Seen with both restrictive / obstructive dx
• Right ventricular hypertrophy and dilation
  secondary to pulmonary disease
• Can cause right heart failure and is major cause
  of death in COPD clients
• Elevated PVR

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Chronic vs. Acute Respiratory Failure

• Chronic Respiratory Insufficiency
• Acceptable level of gas exchange is maintained
  only through cardiopulmonary compensatory
  mechanisms
• Slow onset, progressive in nature
• Can lead relatively normal life
• Always has some degree of hypoxemia
• ABGs Normal pH, high PaCO2, high HCO3
• Always in state of impending respiratory failure

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Acute Respiratory Failure

• One of most common problems seen in critical care
• Life-threatening
• PaO2 lt 60 mmHg
• SaO2 lt 90
• PaCO2 gt 50 mmHg
• pH lt 7.30
• Always hypoxic
• Can be ventilatory, oxygenation, or both

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Ventilatory Failure

• V inadequate Q normal
• Complications
• MODS, ARDS, Acute Tubular Necrosis
• Clinical Criteria
• PaCO2 gt 50, pH lt 7.30
• Course ? PaO2 ? ?RR ? ? PaO2 ?PaCO2

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Oxygenation Failure

• V normal Q decreased
• PaO2 lt 60 mmHg
• CO2 able to diffuse
• Right to left shunt occurs
• Caused from
• ARDS, pulmonary embolus, acute asthma attack,
  pneumonia
• When fatigue occurs, ventilatory failure also
  occurs

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Combination Failure

• Course
• ? RR also leads to ? metabolic rate ? ? O2
  consumption by tissues ? ? CO2 produced ?
  progression of ? CO2 and ? O2
• If condition that causes ARF not managed
  adequately, level of respiratory failure worsens,
  increased work of breathing results, and
  respiratory muscle fatigue develops

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Acute Respiratory Failure

• Nursing Diagnoses
• Impaired Gas Exchange
• Ineffective Breathing Pattern
• Risk for Aspiration
• Imbalanced Nutrition
• Anxiety
• Deficient Knowledge

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Acute Respiratory Failure

• Medical Management
• Treat underlying cause
• Increase oxygenation
• Increase ventilation
• Facilitate removal of secretions and dilate
  airways
• May need neuromuscular paralytics

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Acute Respiratory Failure

• Medical Management
• Correct acidosis
• Nutritional support
• Malnutrition decreases ventilatory drive and
  muscle strength
• Overfeeding increases CO2 production
• Nutritional support initiated before 3rd day of
  mechanical ventilation for well-nourished within
  24 hours for malnourished

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Acute Respiratory Failure

• Nursing Interventions
• Positioning
• Prevent desaturation
• Rest and controlled activity
• Sedation to control anxiety
• Control fever
• Continuous pulse oximetry
• Promote secretion clearance
• Monitor intake / output

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Acute Respiratory Failure

• Nursing Interventions
• Client / Family Teaching
• Pathophysiology of disease and specific etiology
• Precipitating factor modification
• Importance of taking medications
• Breathing techniques
• Measures to prevent infection
• SS of infection
• Cough enhancement techniques

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Acute Respiratory Distress Syndrome (ARDS)

• Distinct type of acute lung injury that leads to
  severe respiratory failure
• Diffuse inflammatory injury to alveolar-capillary
  membrane ? noncardiogenic pulmonary edema
• PaO2/FIO2 ratio lt 200 mmHg normal is gt350

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ARDS

• Precipitated by direct or indirect injury
• Presentation
• Onset occurs rapidly except in chronic disease
  where onset more insidious
• Early Increased resp. distress that progresses,
  CXR initially clear acute respiratory alkalosis
  from hyperventilation absent or mild hypoxemia

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ARDS

• Progression of Presentation
• Cyanosis and accessory muscle use cough and
  expectoration typical of pulmonary edema ABGs
  Increased hypoxemia refractory to increasing
  concentrations of oxygen PFTs consistent with
  restrictive lung disease bilateral infiltrates
  on CXR
• PaO2 lt 55 FIO2 gt 50

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ARDS

• Mortality rate ranges from 50-85 highest with
  sepsis
• Survivors have slow lung repair that terminates
  at 6 months following onset 50 have no
  significant permanent damage

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ARDS

• Nursing Diagnoses
• Impaired gas exchange
• Fatigue
• Imbalanced nutrition
• Risk for injury, aspiration and / or infection
• Anxiety
• Compromised family coping
• Disturbed sleep patterns

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ARDS

• Interventions
• O2 at lowest level to support tissue oxygenation
• Position important
• PEEP or CPAP
• Assess lung sounds q hour
• Tension pneumothorax
• Sedation / paralysis
• Ventilation
• Permissive hypercapnia Pressure control Inverse
  Ratio

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ARDS

• Interventions
• Tissue Perfusion
• Investigational
• Extracorporal/Intracorporal Gas Exchange (ECMO)
  is last resort
• Surfactant Therapy
• Partial liquid ventilation
• Inhaled nitric oxide

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ARDS

• Nursing Management
• Prone positioning when possible
• Improve oxygenation
• Administer high FIO2
• Non-rebreather or CPAP
• Mechanical ventilation if severe hypoxemia or CV
  instability
• PEEP
• Muscle relaxation sedation

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ARDS

• Nursing Management
• Improve oxygenation
• Decrease oxygen consumption
• Improve oxygen carrying capacity transfusion
• Minimize airway suctioning avoid oxygen
  desaturation
• Reduce anxiety
• Achieve effective communication

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ARDS

• Prevention of Complications
• At higher risk of developing nosocomial pneumonia
• Ventilator dependent for weeks - months
• Additional
• Barotrauma
• Pulmonary embolism
• GI bleeding
• Electrolyte disturbances
• Maintain adequate nutrition
• Monitor I/O

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Pulmonary Emboli (PE)

• Clot or other matter lodges in pulmonary arterial
  system, disrupting the blood flow to a region of
  the lungs
• Majority from DVT
• Virchows triad Hypercoagulation, injury to
  vascular endothelium, and venous stasis (most
  significant)

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Pulmonary Emboli

• Presentation
• Increased dead space Area of lung receiving
  ventilation without being perfused ? work of
  breathing
• Localized bronchoconstriction to promote
  redistribution of ventilation to perfused areas
  of lungs ? atelectasis

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Pulmonary Emboli

• Presentation
• Compensatory shunting ? hypoxemia
• Hemodynamic consequences
• Pulmonary hypertension ?? workload of R ventricle
  ? R ventricular failure ? ? L preload ? ? CO ? ?
  BP and shock
• Common presenting symptoms Dyspnea, pleuritic
  pain, cough

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Pulmonary Emboli

• Presentation
• Common physical signs Tachypnea, crackles,
  tachycardia, decreased breath sounds over
  affected areas, friction rub. S3 / S4, cough
• Massive PE
• Cyanosis, restlessness, anxiety, confusion,
  hypotension, cool, clammy skin, decreased UO
• Submassive Pleuritic chest pain, hemoptysis
• Most have decreased SaO2

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Pulmonary Emboli

• Labs
• ABGs Hypoxemia, respiratory alkalosis
• EKG Sinus tachycardia, T-wave inversion (v1-V4)
• CXR will vary from normal to abnormal little
  value in confirming PE
• Confirmation of high-probability V/Q scan,
  positive pulmonary angiogram, or strong suspicion
  with abnormal findings on DVT studies

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Pulmonary Emboli

• Medical Management
• Prevention is key!
• Treatment
• Prevent recurrence
• Heparin and coumadin
• Stop Heparin with INR 3.0 and continue coumadin
• Heparin to maintain PTT 1.5-2.5 X control
• Continue coumadin 3-6 months unless recurrent
  venous thrombosis, then 6-12 months

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Pulmonary Emboli

• Medical Management
• Greenfield filter into vena cava when
  anticoagulation contraindicated
• Treat current PE
• Thrombolytic agents have limited success and
  reserved for massive PE and hemodynamic
  instability
• Reverse hemodynamic effects
• Inotropic agents
• IV Fluids

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Pulmonary Emboli

• Nursing Management
• Prevention major focus
• Optimize oxygenation and ventilation
• Monitor for bleeding
• Client education
• Decrease anxiety
• Family support
• Review nursing diagnosis from N2903!

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Severe Acute Respiratory Syndrome (SARS)

• First identified China 11/02
• Mortality rate 8-10
• Higher in lower SEC
• Pathophysiology
• New virus from coronaviruses
• RNA as genetic material
• Coronaviruses cause many common colds
• SARS mutated from common cold

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SARS

• Lives in respiratory passages
• Develops at temperature slightly below core body
  temp
• Easily spread via airborne droplets
• Detail to isolation precautions must be taken
• Survival on non living objects short
• Those at greatest risk are individuals in close
  contact w/ infected persons
• Portal of entry is mucous membranes, eyes, nose,
  throat

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SARS

• Assessment / Clinical Manifestation
• Mimics other respiratory infections
• Fever gt 100.4 F
• Headache
• General body aches
• Malaise
• Mild cold symptoms
• Runny nose, sore throat, watery eyes

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SARS

• Assessment
• Within 2-7 days
• Dry cough
• Difficulty breathing
• Hypoxia
• Cyanosis
• Low O2 saturation
• Feelings of breathlessness / air hunger
• CXR similar to pneumonia / RDS

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SARS

• Diagnosis
• Made by r/o other infections
• No rapid test exists at present time
• At day 28
• Serum shows positive presence of RNA of SARS
• Client generally well or deceased by this time
• Currently, no known SARS cases in the world
• http//www.cdc.gov/ncidod/sars/situation.htm
• Last cases April, 2004

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SARS

• Interventions
• No known effective treatment at this time
• Standard AB therapy or antiviral therapy not
  effective
• Should focus on strength and energy conservation
• Improve overall well being of client and clients
  immune system

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SARS

• Interventions
• Oxygen therapy if hypoxia develops
• If gas exchange not improved, intubation and
  mechanical ventilation may be required
• Respiratory therapy to aid in mucous secretion
  movement may be beneficial and promote comfort
• Bacterial pneumonia may occur and should be
  treated
• Sputum cultures may be necessary

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SARS

• Interventions
• Education of client and family
• Relieve anxiety
• Promote comfort
• Position as appropriate
• Prevention is key!
• Handwashing
• Strict airborne isolation
• Particulate masks should be worn
• N-99 / N-95 /N-100 (used w/ TB)
• Strict contact precautions
• Use eye shields / gowns / gloves

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SARS

• Interventions
• Client should wear mask if outside isolation
  environment
• Evaluation
• Client / family return to normal functioning
  state
• Anxiety decreased
• Air exchange appropriate

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Aspiration Pneumonia

• Review N2903 notes r/t aspiration pneumonia
• Interventions
• Establish airway
• Minimize pulmonary damage
• Right side slight Trendelenburg
• Bronchoscope
• To remove large particulate
• To confirm unwitnessed aspiration

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Aspiration Pneumonia

• Interventions
• Support / optimize ventilation / oxygenation
• Monitor volume status
• Dont forget to record IO
• Appropriate positioning
• Identify patients at risk
• Institute safety measures

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Status Asthmaticus

• Review N2903 notes!
• Know ABG changes
• Hypocapnea and respiratory alkalosis at onset
• Developing / progressing to respiratory and
  metabolic acidosis
• Classic deterioration in PFTs seen
• Monitor closely / maintain calm, secure
  environment
• Ventilator support may be needed in deteriorating
  conditions

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Pleurisy

• Ineffective breathing pattern r/t pain
• Review N2903 notes!
• Offer pain medication / alternative pain therapy
  as needed
• Teach splinting techniques
• Treat underlying cause
• Monitor for pleural effusion!

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Respiratory Syncytial Virus

• Updated information can be found at
• http//www.rsvinfo.com/sequelae/sequelae.html
• Generally seen with newborns
• Premature infants at greatest risk
• Most children develop dx by age three
• Can cause RDS in children
• Antiviral therapy may be indicated

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RSV

• Can play a major role in development of COPD /
  asthma in children
• Severe implications in those immunocompromised
  children
• Upper and lower respiratory tracts infected
• Lower most common sight
• Nursing / medical interventions dependent upon
  severity
• Family support / education important

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Whats Next?

• Class on 1/25
• Ventilator management
• Nursing interventions r/t ventilator dependent
  clients
• Seminar on 1/27
• ABG review
• Compensated acidosis / alkalosis
• Worksheet for practice problems
• Exam 2/7

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Questions?