Patient Assessment: Patient Assessment: Respiratory System Respiratory System

NUR 409NUR 409

Fall 2014-2015 Fall 2014-2015

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OUT LINEOUT LINE Regulation of respiration.. Assessment:a. HX.b. PE.c. Diagnostic studies.

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Regulation of RespirationRegulation of Respiration*Respiratory Centera. Pons= controls rate & depth of inspiration.b. Medulla Oblongata= control rhythm of respiration.

** Chemoreceptora. Center-medulla oblongata: Monitor arterial blood indirectly by

sensing changes in the PH of CSF. Sensitive to very small changes in PH. Increased levels of CO2= low PH==

stimulates respiratory center to increase depth & rate of ventilation.

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b. Peripheral: aortic bodies & carotid bodies)

Located in aortic bodies of aortic arch & carotid bodies at bifurcation of the carotids.

Primarily sensitive to changes in O2 levels in the arterial blood, do detect changes in CO2 & PH.

As PaO2 & PH decrease= peripheral chemo-receptors stimulate respiratory center to increase ventilation.

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Peripheral chemoreceptors not sensitive as central chemoreceptors

PaO2 must drop to approximately 60 mmHg before the peripheral chemoreceptors have much influence on ventilation.

It become the major stimulus to ventilation when center chemoreceptors are reset by chronic hypoventilation.

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Assessment of Respiratory Assessment of Respiratory FunctionsFunctions

Health History:a. Dyspnea, Orthopnea, PND.b. Cough, Throat soreness.c. Sputum Production.d. Chest pain (pleuritic, intercostal,

generalized chest pain).e. Habit HX (smoking).f. Occupational exposure to allergens/

environmental pollutants.g. Past personal/ family health HX.h. Voice changes.i. Fatigue & weight changes.j. medication

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Sputum productionSputum productionYellow, green, or brown sputum

typically signifies bacterial infection.clear or white sputum may signify

absence of bacterial infection. The color comes from white blood

cells in the sputum. Rust-colored sputum (yellow sputum

mixed with blood) may signify tuberculosis.

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Sputum productionSputum productionMucoid, viscid, or blood-streaked

sputum is often a sign of a viral infection.

Persistent slightly blood-streaked sputum is present in patients with carcinoma.

Large amounts of clotted blood are present in the sputum of patients who have suffered a pulmonary infarct.

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CoughCoughcough can be stimulated by external

agents, by inflammation of the respiratory mucosa, or by pressure on an airway caused by a tumor.

caused by smoking, allergies, heartburn, asthma, and certain medicationsfrom the patient about the cough should include onset,

precipitating factors, timing, frequency, and whether the

cough is productive or non.

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Past Medical HistoryPast Medical HistoryAny lung problems such as asthma or TB?

Exposure to lung disease?Any chest surgery or diagnostic studies?

How many pillows do you use to sleep?

Allergies?History of smoking?Medications? Vaccine?Any O2 use at home?

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Risk factorsRisk factorsSmoking

◦Pack years = #of pack/day x # of years

Personal / family historyOccupationAllergensRecreational exposure

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AssessmentAssessment

◦LOOK - LISTEN - FEEL Look for Symmetry of Chest Expansion Look for Signs of Increased Respiratory

Effort Look for Changes in Skin Color Listen for Air Movement at Mouth & Nose Listen for Air Movement in Peripheral

Lung Fields Feel for Air Movement at Mouth & Nose Feel for Symmetry of Chest Expansion

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Physical assessmentPhysical assessmentCh. Ch of respirations:

Respiratory rate, depth, and pattern of respiration

Labored breathing, use of accessory muscles

Cyanosis of skin A/P diameter of chest, and

patient postureChest expansion

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Physical assessmentPhysical assessment Retractions: subclavicular, Substernal,

intercostals. Breathing Sounds. Sputum. Mental status. V/S.Chest deformities or scarsIE ratioPosition of trachea.

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AssessAssess

Signs of Respiratory Distress Nasal Flaring Tracheal Tugging Retractions Accessory Muscle Use Use of Abdominal Muscles on Exhalation

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Inspection of Chest:Inspection of Chest:Kyphosis, scoliosis, barrel chest.Kyphosis, scoliosis, barrel chest.

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Inspect Inspect Clubbing of the fingersClubbing of the fingers

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PalpationPalpationTactile fremitus Subcutaneous emphysema Thoracic expansionTrachea

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PalpationPalpation

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PalpationPalpation

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Symmetric expansion- place hands of postero-lateral chest wall with thumbs at level of T9 or T10; Slide hands medially to pinch up a small fold of skin between thumb; have person take a deep breath your thumbs should move apart symmetrically

PercussionPercussion

Flat percussion note is a soft, high-pitched sound. It is more likely to be heard if a large pleural effusion is present in the lung beneath the examining hand.

Dull percussion note is medium in intensity and pitch. It is heard if atelectasis or consolidation due to pneumonia, pulmonary edema, or pulmonary hemorrhage.

A tympanic drumlike sound is a high-pitched noise heard if asthma or a large pneumothorax is present.

See Table (24-1).

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PercussionPercussion

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PercussionPercussion

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AuscultationAuscultationTracheal breath sounds

◦Over trachea, loud and harsh Bronchial breath sounds :Air in large

passageways,◦Over large airways they are normal;

anywhere else they are not normal Bronchovesicular breath sounds

◦Medium in pitch; heard over bronchiolesVesicular breath sounds: air filling

the alveolar sacs◦Heard over distal airway; quiet, low

pitched

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Respiratory SoundsRespiratory Sounds

Auscultation:

◦Throat◦Intercostal spaces◦Triangle of auscultation

◦Under the clavicle

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AuscultationAuscultationa. Evaluate the presence and quality of normal breath sounds.b. With flat diaphragm of stethoscope listen at least one full respiration in each locationc. Compare side to side and top to bottom ( Go from left to right and then down or from right to left and then downd. analyze breath soundse. detect any abnormal soundsf. examine sounds produced by spoken word

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AusculatationAusculatation

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Voice soundsVoice sounds◦Assessed when abnormalities noted◦Increased when sound travels

through solid or liquid Consolidation of lung, pneumonia,

atelectasis, pleural effusion, tumor, abscess

◦Bronchophony: 99 – loud and clear◦Whispered Pectriloquy: 1, 2, 3 – loud◦Egophony – ‘E’ – heard as an ‘A’

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Adventitious SoundsAdventitious SoundsSnoring respiration

◦Upper Airway◦Partial obstruction of the upper

airway by the tongueStridor

◦High pitched crowing sound◦Usually heard on inspiration◦Indication of a tight upper airway

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Adventitious SoundsAdventitious SoundsWheezing

◦Whistling sound◦Usually heard on expiration◦Indication of narrowing of lower

airways caused by: Bronchospasm Edema Foreign material

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Adventitious SoundsAdventitious SoundsRhonchi

◦Rattling sound◦Caused by mucus in larger airways

Rales◦Fine crackling sound◦Indication of fluid in the alveoli

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CracklesCrackles

Indicate AtelectasisBronchitisPneumoniaPulmonary edemaPulmonary fibrosis (dry crackles

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Pulse OximetryPulse Oximetry

PaO2 and O2 saturationPaO2 and O2 saturation

PaO2 is the partial pressure of O2-measures O2 dissolved in the plasma 3% of arterial oxygen content.

O2 Saturation measures the amount of Hgb saturated with oxygen. 97% of arterial content

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Pulse OximetryPulse Oximetry Measure O2 sat which reflects the

arterial oxygen saturation of hemoglobin (SaO2).

N value (93%-99%). Reading is unreliable if pt:a. On vasoconstrictor meds.b. Has severe anemia.c. Use IV dyes.d. Smokers who have high levels of

carboxyhemoglobin.

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Pulse Oximetry Pulse Oximetry Percentage of O2 saturation

=Amount of O2 Hgb is carrying /amount of O2 Hgb can cary

(amount of O2 Hgb can cary =1.34)

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Oxyhemoglobin Dissociation Oxyhemoglobin Dissociation CurveCurve

Shows relationship between PaO2 and O2 saturation

These two values trend in the same direction

Curve allows us to estimate PaO2 based on non-invasive peripheral O2 saturation.

If the curve is shifted to the Rt it means decrease affinity & increase perfusion.

If the curve is shifted to the Lt it means increase affinity & decrease perfusion.

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PaO2 and O2 saturationPaO2 and O2 saturation

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Right shift

Acidosis

Hyperthermia

Hypercarbia

Left shiftAlkalosisHypothermiaHypocarbia

•it means decrease affinity & increase perfusion.

•it means increase affinity & decrease perfusion.

Factors That Affect the Factors That Affect the Oxyhemoglobin Dissociation Oxyhemoglobin Dissociation CurveCurve

Right shift

AcidosisHyperthermiaHypercarbia

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Left shiftLeft shift

AlkalosisAlkalosis HypothermiaHypothermia HypocarbiaHypocarbia

Oxyhemoglobin Dissociation Oxyhemoglobin Dissociation CurveCurveClinical implications

◦Right shift more common in high acuity patients

◦Body temperature can be controlled to reduce oxygen consumption

Table 33-7 Table 33-7 Conditions That Conditions That

Alter Oxygen Alter Oxygen Consumption Consumption

End-Tidal Carbon Dioxide Monitoring End-Tidal Carbon Dioxide Monitoring (ETCO2)(ETCO2)

Measures the levels of CO2 at the end of expiration when the percentage of CO2 dissolved in the arterioles (PaCO2) becomes almost equivalent to percentage of alveolar CO2 (PaCO2).

Therefore, ETCO2 can be used to estimate levels of alveolar CO2.

Used to estimate PaCO2.

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ETCO2ETCO2ETCO2 values are obtained by

monitoring samples of expired gas from an endotracheal tube, an oral airway, or a nasopharyngeal airway.

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Mixed venous oxygen saturation Mixed venous oxygen saturation (SvO2)(SvO2)

a parameter that can be measured to evaluate the balance between oxygen supply and oxygen demand.

For complete mixing of the blood, it is necessary to obtain a blood sample from a pulmonary artery catheter.

Normal mixed venous oxygen saturation is 60% to 80%

An SvO2 of 40% to 60% may occur in heart failure, and values less than 40% may indicate profound shock.

A decrease in SvO2 often occurs before other hemodynamic changes

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Mixed venous oxygen saturation Mixed venous oxygen saturation (SvO2)(SvO2)A low SvO2 may be caused by a decrease

in oxygen supply to the tissues or an increase in oxygen use due to a high demand.

A decrease in oxygen supply results from low hemoglobin, hemorrhage, or low cardiac output.

increase in oxygen demand results from hyperthermia, pain, stress, shivering, or seizures.

Elevated SvO2 values are associated with increased delivery of oxygen (high fraction of inspired oxygen [FIO2]) or with decreased demand from hypothermia, hypothyroidism, or anesthesia.

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Diagnostic TestDiagnostic Test

a. Chest X-ray (CXR): Used to detect anatomical structure

of the chest & diaghram. Dense materials like the bones or

heart appear opaque or white. Air filled space (lungs) appears black. Soft tissue or fluid filled areas appear

gray.

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Chest X-RayChest X-Ray

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Components of Pulmonary Components of Pulmonary Gas ExchangeGas ExchangeVentilation Diffusion

◦Affected by pressure gradient, surface area and thickness of alveolar-capillary membrane

Perfusion◦Affected by hemoglobin (Hb)

concentration, affinity of oxygen to Hb, and blood flow

Factors That Impair Factors That Impair Pulmonary Gas ExchangePulmonary Gas ExchangeVentilation-perfusion

mismatching◦Pulmonary embolus◦Pneumothorax

Ventilation Perfusion Ventilation Perfusion Mismatch Mismatch Physiological Shunt (low V-P ratio)

pneumonia, atelectatsis, tumor Alveolar dead space (high V-P

ratio)Pulmonary infarction, Pulmonary

embolism, decrease COPSilent unit : when ventilation and

perfusion low, ARDS, Pneumothorax

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b. b. Ventilation-Perfusion Lung Scan:Ventilation-Perfusion Lung Scan:

Detects the percentage of the lung that is normally functioning.

Diagnose & locate pulmonary emboli. Assess pulmonary blood supply. Is a nuclear imaging test composed of 2

parts:a. Ventilation Scan: Inhalation of radioactive

gas.b. Perfusion Scan: radioactive materials given

IV & scan to visualize blood supply to lungs. Not useful diagnostic tool in pts who are

dependent on MV.

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Pulmonary Angiography: Rapid injection of radiopaque material into

arm, femoral vein, or pulmonary artery. Indicated for pulmonary embolism. The test indicates impaired blood flow to a

vessel.Sputum for cytology or analysis: indicated to examine for culture sensitivity. Assess for cytology. Culture of acid-fast bacilli to detect the

presence of TB & mycobacterium. ( 3 serial specimens over 3 days).Before taking the specimen to the

lab, make sure that you collected a sputum and not saliva.

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Bronchoscopy Direct visualization of the larynx, trachea & bronchi by a

flexible fiber optic bronchoscope. Indicated to detect tissues, collect secretions & obtain

biopsy. Examine the extent of the pathological problem. Used to remove foreign bodies or lesions. Patient Preparations:

a. CXR, ABG, Clotting studies.

b. IV sedation/ analgesia.

c. If purpose of Bronchoscopy is therapeutic (Drug that suppress cough or secretions are avoided. (Intratopical anesthesia, atropine, codeine).

Complications: laryngospasm, fever, dysrhythmias, Pneumothorax, arrest, hemodynamic changes.

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ThoracentesisThoracentesis

Inserting a needle into pleural space. Indicated to remove fluid/ or air, obtain specimen, give

medication. Patient Preparations:a. CXR, Clotting studies.b. Patient teaching.c. Local anesthesia.d. Pt in sitting position (chair, or edge of bed) e arms &

shoulders up). Post procedures:a. Comfort measures.b. Send specimen to lab.c. Sterile dressing.d. Assess for complications: Pneumothorax, respiratory

distress, pain, hypotension & pulmonary edema.

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Pulmonary/ or Ventilatory Pulmonary/ or Ventilatory Function TestFunction Test Measures the ability of the chest &lungs to

moves air into & out of the alveoli. Pulmonary function tests help distinguish

between obstructive and restrictive pulmonary diseases.

It include measurements of lung volume, capacity & dynamic.

The above measures are affected by age, disease, exercise, gender, ht & body size.

a. Volume measurements (VT, IRV, EVR, RV).b. Capacity measurements (IC, FRC, VC, TLC).c. Dynamic measurements (provide information

about airway resistance & amount of energy expended in breathing (work of breathing).

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Dynamic measurementsDynamic measurements RR. Minute Volume/ Ventilation: volume of air inhaled

& exhaled /min. Dead Space: is the part of tidal volume that does not participate in

alveolar gas exchange. Is the air contained in the airways (anatomical dead

space 140 ml) plus the volume of alveolar air that is not involved in gas exchange (physiological dead space).

Calculated by subtracting the partial pressure of arterial carbon dioxide (PaCO2) from the partial pressure of alveolar carbon dioxide (PACO2).

N value of dead space in healthy adults is typically less than 40% of the tidal volume.

The dead space-tidal volume ratio is used to follow the effectiveness of MV.

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Residual volume: approximately 20% of total lung capacity in young adult. Increase e age.

FEC: decrease in Ascitis and supine position. Wt of abdomen contents forces the diaphragm upward.

Increase in recoil lung in pt e sarcoidosis.

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Lung CapacitiesLung CapacitiesComposed of 2 or more lung volumes.Useful measurements in clinical

situation.Total lung capacity: maximum lung

volume after full inspiration.At TLC, the force generated by a

maximum contraction of the inspiratory muscles equals the recoil of the lung. That’s means: TLC dependent on the strength of resp muscle & elastic resistance of lung, chest wall,…..

Its divided to 4 types.

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Lungs Volumes and Lungs Volumes and CapacityCapacity

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CALCULATIONCALCULATIONTLC= RV+IRV+TV+ERV.VC=IRV+TV+ERV=TLC-RV.FRC=RV+ERV.IC=TV+IRV.

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Dynamic MeasurementsDynamic Measurements

Alveolar Ventilation: The volume of tidal air that is involved in alveolar gas exchange.

This volume is represented as volume per minute by the symbol VA. VA is a measure of ventilatory effectiveness.

It is more relevant to the blood gas values than either the dead space or tidal volume because these last two measures include physiological dead space.

VA is calculated by subtracting the dead space (VD) from the tidal volume (VT) and multiplying the result by the respiratory rate (f ): V.A =(VT . VD )× f

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IMPORTANCE IMPORTANCE IN RESTRICTIVE DISEASE:Decrease VC, decrease TLC, RV,

FRC.

OBSTRCUTIVE DIESEASE:Decrease VC, INCREASE TLC, RV,

FRC.

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Arterial Blood GasesArterial Blood GasesDrawn from radial, femoral,

brachial arteriesInvasive procedureCaution must be taken with

patient on anticoagulantsHelps differentiate oxygen

deficiencies from primary ventilatory deficiencies from primary metabolic acid-base abnormalities

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Uses of Arterial Blood GasesUses of Arterial Blood Gases

Indication of oxygenation status

Determination of acid-base state

Assess ventilation

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Acid Base RelationshipAcid Base Relationship

This relationship is critical for homeostasis

Significant deviations from normal ph ranges are poorly tolerated and may be life threatening

Achieved by respiratory and renal systems

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ABG Normal ValuesABG Normal Values

PaO2: 80-100 mmHg (partial pressure of oxygen in arterial blood).

SaO2: 96-100% arterial O2 saturation.pH: 7:35-7:45 over all state.PaCO2: 35-45 mmHg respiratory

component.HCO3: 22-26 mEq/L (metabolic

component).BE: Base excess +2- -2

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Acid/base RelationshipAcid/base Relationship

H2O + CO2 H2CO3 HCO3 + H+

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Respiratory Metabolic

Ratio of CO2 and HCO3Ratio of CO2 and HCO3

Normal ratio is 1 (CO2) to 20 (HCO3)

Abnormal creates imbalance

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Respiratory ImbalancesRespiratory Imbalances

Respiratory Acidosis **********too much CO2

Respiratory Alkalosis **********too little CO2

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Metabolic ImbalancesMetabolic Imbalances

Metabolic Acidosis *********too little HCO3

Metabolic Alkalosis *********too much HCO3

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Know ThisKnow This

CO2 is an acidRegulated by the

lungs Too much causes

acidosis

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HCO3 is a baseHCO3 is a base Regulated by the Regulated by the

kidneyskidneys Too much causes Too much causes

alkalosisalkalosis

PHPH Indirect measure of H+ ion

concentration. Ratio of base (HCO3) to acid CO2. Acid give up (donate) H+ ions, while

bases pick up H+ ions. Body maintains a slightly alkaline pH

of 7:35-7:45. Metabolic & Respiratory processes

work together to keep Hydrogen level (H+) in a normal range.

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Regulators of Acid /BaseRegulators of Acid /Base

a. Buffers primary regulator.Act immediately.Present in blood & tissue.Take up extra H+ ions or release

H+ (eg bicarbonate, proteins & hemoglobin). a

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Buffer systemsBuffer systems

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Regulators of Acid /BaseRegulators of Acid /Baseb. Respiratory system: Eliminates CO2.Respiratory center in medulla controls

breathing.Increased respirations leads to

increased CO2 elimination from body & decrease CO2 in blood.

Decreased respirations leads to decrease CO2 elimination from body & increase CO2 in blood.

Responds within minutes to hours to changes in Acid / Base.

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Regulators of Acid /BaseRegulators of Acid /Base

C. Renal SystemSecrets H+ ions & reabsorbs

bicarbonate (HCO3) ions. Reabsorbing & secretion of

electrolytes like (Na, K). Responds within hours to days.

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What Are the What Are the Compensations?Compensations?

In chronic respiratory acidosis (COPD) the kidneys increase The elimination of H+ and absorb more HCO3. The ABG will show NL ph, CO2 and HCO3

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ABG Normal ValuesABG Normal ValuesPaO2: 80-100 mmHg (partial

pressure of oxygen in arterial blood).SaO2: 96-100% arterial O2 saturation.pH: 7:35-7:45 over all state.PaCO2: 35-45 mmHg respiratory

component.HCO3: 22-26 mEq/L (metabolic

component).BE: Base excess +2- -2

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ABGsABGsAcidemia: Acid condition of the blood

in which PH < 7.35.

Alkalemia: Alkaline condition of the blood in which PH >7.45.

Acidosis: the process causing acidemia.

Alkalosis: the process causing alkalemia.

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How to obtain ABGsHow to obtain ABGs Hepranized syringe. Blood from artery. On Ice. Prompt delivery to lab.Include:a. Time drawn.b. FIO2.c. O2 delivery rate & method

(ventilatory method).d. Patient temperature.e. Pulse Oximetry O2 saturation.

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Interpretation of ABGsInterpretation of ABGs

a. Evaluate PH: this determines acidosis or alkalosis.

7.40 is the middle of the normal range of 7.35-7.45.Value below 7.40 is moving toward acidosis.Value above 7.40 is moving toward alkalosis.

b. Evaluate Respiratory component (PaCO2):

If PaCO2 < 35, the value is alkalotic. If PaCO2 > 45, the value is acidotic.

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Interpretation of ABGsInterpretation of ABGsc. Evaluate metabolic component

(HCO3): If HCO3 > 26 mEq/L, the value is alkalotic. If HCO3 <22 mEq/L, the value is acidotic.d. Determine which component (PaCO2 or HCO3) matches

the PH.

e. If the PH is increased or decreased is the underlying disorder respiratory or metabolic:

Respiratory:Decrease PH, Increase PaCO2.Increase PH, Decrease PaCO2.Metabolic:Decrease PH, Decrease HCO3.Increase PH, Increase HCO3. If both respiratory & metabolic components

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Interpretation of ABGsInterpretation of ABGs

e. Determine the degree of compensation:

a. Absent: * The PH is not within normal range.** The components (CO2 & HCO3) that does not

match the PH imbalance is still within its normal range.

b. Partial:* The PH is not within normal range.** The components (CO2 & HCO3) that does not

match the PH disorder is below or above the normal range.

C. Complete: The PH is within normal range, & both CO2 &

HCO3 are either above or below normal range.

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Metabolic AcidosisMetabolic AcidosisPh 7.30

Paco2 40

Hco3 15

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Metabolic AcidosisMetabolic AcidosisFailure of kidney function.

Blood HCO3 which results in availability of renal tubular HCO3 for H+ excretion

Ph < 7.35 Hco3 < 22

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Causes of Metabolic Causes of Metabolic AcidosisAcidosis

Renal failure

Diabetic ketoacidosis

Lactic acidosis

Excessive diarrhea

Cardiac arrest

Poisoning (acetylsalicylic acid)04/21/23 102

S&SS&SLethargy

Nausea & Vomiting.

Dysrhythmia.

Coma.

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Treatment of Metabolic Treatment of Metabolic AcidosisAcidosisRX of underlying cause.Monitor I&O.Monitor for dysrhythmia.Protect against infection.Give sodium bicarbonate.

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Respiratory AlkalosisRespiratory AlkalosisPh 7.50

Paco2 30

Hco3 22

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Causes of Respiratory Causes of Respiratory AlkalosisAlkalosis Hyperventilation

PE. Panic disorder Brain stem disease.

Pain Anxiety

Pregnancy Acute anemia Salicylate overdose

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S & SS & SDizziness.Tingling.Numbness.Restlessness.Agitation.Tetany.

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Treatment of Respiratory Treatment of Respiratory AlkalosisAlkalosisSedation.Reassure &Support patient.Breath in paper bag for attack of

hyperventilation.Decrease RR.Decrease tidal volume.

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Metabolic AlkalosisMetabolic AlkalosispH 7.50

PCO2 40

HCO3 30

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Metabolic AlkalosisMetabolic Alkalosis plasma bicarbonate

pH > 7.45 HCO3 > 26

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Causes of Metabolic Causes of Metabolic AlkalosisAlkalosis loss acid from stomach or kidney Diuretics.

Adrenal disease. Corticosteroid therapy

excessive alkali intake (Sodium bicar over load).

hypokalemia

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S&SS&SDullness.Weakness.Dysrhythmias.Tetany.Hypokalemia.

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Treatment of Metabolic Treatment of Metabolic AlkalosisAlkalosisTreatment of underlying cause.Monitor I & O.K replacement therapy.Ammonium chloride.

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Respiratory AlkalosisRespiratory AlkalosisToo much CO2 exhaled

(hyperventilation)

PCO2, H2CO3 insufficiency = ph

Ph > 7.45 Pco2 < 35

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Respiratory AcidosisRespiratory Acidosis Ph 7.30

Paco2 60

Hco3 26

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Respiratory AcidosisRespiratory AcidosisToo much CO2

pH < 7.35

CO2 > 45

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Causes of Respiratory Causes of Respiratory AcidosisAcidosisNeuromuscular diseaseHead injurySedatives, narcoticsAtelectasisObstructed airway (COPD).Inappropriate vent settingsAlveolar hypoventilation

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S&SS&SDyspnea.Headache.Mental confusion.Pallor.Sweating.Apprehension, restlessness.

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Treatment of Respiratory Treatment of Respiratory AcidosisAcidosisAggressive CHEST

PHYSIOTHERAPY.SUCTION.INCREASE RR.INCREASE TIDAL VOLUME.

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ABG Analysis(example)ABG Analysis(example)

pH 7.21, Pa02 70mmHg, PaCO2 63mmHg, HC03 27mEq/L

1. Evaluate the pH. pH is not in normal range, but is decreased (acidosis).

2. Evaluate the PaC02. PaC02 is elevated.

3. Evaluated the HC03. HC03 is slightly elevated

4. Describe the acid base status.04/21/23 120

Step 1Step 1Evaluate the pHNormal 7.35-7.45Below 7.35=acidemiaAbove 7.45= alkalosisIf a pt has more than one acid-

base balance at work, the pH identifies the process in control

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Step 2Step 2Evaluate ventilationNormal 35-45mmHggreater than 45= ventilatory

failure and respiratory acidosisless than 35 = alveolar

hyperventilation and respiratory alkalosis

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Step 3Step 3Evaluate metabolic processNormal 21-25HCO3 < 22 = metabolic acidosisHCO3 > 25 = metabolic alkalosis

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Step 4Step 4Determine primary and

compensating disorderWhen both PCO2 and HCO3 are

abnormal, one reflects the primary acid-base disorder and the other reflects the compensating disorder

To decide which is which, check the ph

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Step 4Step 43 states of compensation possible1. Non compensation- alteration of

only pco2 or HCO32. Partial compensation- when both

pco2 and HCO3 are abnormal and because compensation is incomplete, the ph is also abnormal;

3. Complete compensation- when both pco2 are abnormal, but because compensation is complete, the ph is normal

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Step 5Step 5Evaluate oxygenationNormal 80-100mmhgPO2 60-80 = mild hypoxemiaPO2 40-60= moderate

hypoxemiaPO2 below 40 = severe

hypoxemia

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Step 6Step 6InterpretFinal analysis should include Degree of compensation The primary disorder The oxygenation statusEx-”partially compensated

respiratory acidosis with moderate hypoxemia

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What Are the What Are the Compensations?Compensations?Respiratory acidosis metabolic

alkalosis

Respiratory alkalosis metabolic acidosis

In respiratory conditions, therefore, the kidneys will Attempt to compensate and visa versa

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BE: refer to an excess or deficit, respectively, in the amount of base present in the blood.

indicates whether the patient is acidotic or alkalotic. A negative base excess indicates that the patient is acidotic. A high positive base excess indicates that the patients is alkalotic.

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Base excess beyond the reference range indicates

metabolic alkalosis if too high (more than +2 mEq/L)

metabolic acidosis if too low (less than −2 mEq/L)

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Anion GapAnion GapIts normal to have approximately the

same n of anions and cations circulating in blood . Some of them not measured anion gaps is present.

Helps determine presence and cause of metabolic acidosis

(Na + K)-(Cl + HCO3) = anion gapNormal value is 6-15 (3-11)15 or less is loss of base16 or more gain of acid (increase in n of

unmeasured anion , lactate, ketone bodies…).

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The serum anion gap is useful for determining whether a base deficit is caused by addition of acid or loss of bicarbonate.

Base deficit with elevated anion gap indicates addition of acid (e.g., ketoacidosis).

Base deficit with normal anion gap indicates loss of bicarbonate (e.g., diarrhea). The anion gap is maintained because bicarbonate is exchanged for chloride during excretion.

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Final AnalysisFinal AnalysisCompare to previous ABGLook at patient’s history and

present situationDetermine what is needed to

correct situation

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Case Study #1Case Study #1

Mr. Adams is a 60 y/O with pneumonia. He is admitted with dyspnea, fever, and ABG

pH 7.28CO2 56PO2 70HC)3 25SaO2 89%

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AnswerAnswerUncompensated respir acidosis

with hypoxemia due to pneumonia. Inadequate ventilation and perfusion. Goals improve both vent an oxygenations. Minimum o2

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Case #2Case #2Ms. Stan is a 24 year old college

student. She has a history of Crohn’s disease c/o 4 day history of boody diarrhea. An ABG is obtained:

pH 7.28CO2 43PO2 88HCO3 20SaO2 96%

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AnswerAnswerUncompensated metabolic

acidosis. Excessive loss from diarrhea. No compensation, treat control diarrhea

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Case # 3Case # 3Mr. Like is a 89 y/O nursing home

resident admitted with urosepsis. Over the last 4 hours he has developed SOB and is confused. ABG:

pH 7.02CO2 55pO2 77JCO3 14O2Sat 89%

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AnswerAnswerMeta is secondary to resp failure.

metbolic and resp acidosis with hypoxemial Metabolic is caused by sepsis , The respopressor, acidosis is secondary to resp faiure. ARDS. Treatment is aggressive, mech vent. Vasopressors, bicarb

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Case # 4Case # 4Mrs Lander is a thin, 61y/o COPD

patient. Her ABG:pH 7.37CO2 63pO2 58HC)3 35SaO2 89%

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AnswerAnswerLander has a fully compensated

resp adidosis with hypoxmia. Full compensation normal pH in spite of adid/base disorder. No treatment baseline

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Case #5Case #5Mrs. Doubtfire is found pulseless

and not breathing. After a couple minutes she responds with a pulse and is breathing. ABG:

pH 6.89CO2 70pO2 42HCO3 13SaO2 50%

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AnswerAnswerSevere metabolic an resp

acidosis with hypoxemia. Resp component comes from decreased perfusion, resp comp comes from inadeq ventilation. Treatment is intubation, mech vent

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Case #6 Case #6 You find Mr. Aster in respiratory

distress. H/O diabetes and is febrile. ABG:

pH 7.00CO2 59pO2 86HCO3 14Sao2 91%

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AnswerAnswerMetabolic and respiratory acidosis

hypoxemia. Resp acidosis from pneumonia. Pneumonia has altered his glucose metabolism hyperglycemia and diabetic ketoacidosisl

1. Increase oxygenation, treat pneumonia, administer IV fluids to treat DKA

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Quiz Quiz A 42-year-old male patient had burns over

60% of his body surface area. On admission, his BP was 95/60 mm Hg with a heart rate of 132, respiratory rate of 8, temperature 96[degrees] F (35.5[degrees] C), and SaO2 of 90%. He was oliguric. He was receiving I.V. infusions of propofol and morphine. You use the five-step approach to analyze his ABGs:

* PaO2 of 63 mm Hg and SaO2 of 90% suggest hypoxia based on his age

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Quiz Quiz * pH of 7.20 is consistent with

acidosis* PaCO2 of 52 mm Hg indicates

inadequate pulmonary ventilation to blow off CO2

* HCO3- of 17 mEq/L suggests a

metabolic alteration toward acidosis

Mixed respiratory and metabolic acidosis with hypoxia

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Follow this five-step approach to interpreting your patient's ABGs.1. Is the patient hypoxic? Look at the Pao2 and Sao2.2. What is acid-base balance? Check the pH.3. How is pulmonary ventilation? Look at the Paco2.4. What is the metabolic status? Review the HCO3

-.5. Is there any compensation or other abnormalities? What is the primary cause of acid-base imbalance and which derangement is the result of secondary (compensatory) change?