respiratory (a&p, abg’s, assessment) respiratory case studies

Respiratory (A&P, ABG’s, Assessment) Respiratory case

studies

Ron Pinkston, RRTRespiratory Therapist

Staff Educator/ Team Leader

Chest Tubes

Chest Tubes

COPD

Indications for Oxygen Therapy

Hypoxemia

Excessive Work of Breathing

Excessive Work of Heart

Oxygen Delivery Devices

• Oxygen Cylinder• Nasal Cannula• Simple Mask• Venturi Mask• Partial Rebreather• Non-Rebreather• Continuous Aerosol

Important points to consider!

• Room air is 21% oxygen• The oxygen that comes out of the wall or

oxygen tank is 100% oxygen• Whatever device or amount of flow we use to

deliver the oxygen to the patient will determine the % of oxygen the patient actually inhales (FIO2)

Nasal Cannula

The nasal cannula supplies the patient with low to moderate concentrations of oxygen. Be sure to add humidifier bottle if the nasal cannula is run at > 3 lpm or upon patient request.

Approximate FIO2 at a given liter flow:1 lpm = 24%2 lpm = 28%3 lpm = 32%4 lpm = 36%5 lpm = 40%6 lpm = 44%

24-40% FiO2

Simple Mask

The simple oxygen mask should be run between 6 and 10 lpm to ensure flushing and prevent CO2 accumulation in the face mask. This flow will result in an approximate FIO2 approximately 40 – 60%, depending upon the patient’s ventilatory pattern.Simple masks are most often used on the pediatric patient that does not tolerate a nasal cannula.

Approximately40-60% FiO2

Use caution when using O2 masks on nauseated

patients, due to the increased risk of

aspiration

Venturi Mask

The Venturi mask (or “Venti” mask) delivers a specific FIO2 concentration (ranging between 0.24 & 0.50, depending on the adapter) to the patient using a recommended flow rate.

Venturi masks are most often used for the COPD patient that requires an exact FIO2 with a higher flow than can be given with nasal cannula.

When using the Venturi mask, be sure you do not block the jet port holes with the patient’s blanket or gown. This will effect the FIO2 being delivered.

Exactly24-50% FiO2

Each adapter is specified for FIO2 &

flow

Partial Rebreather MaskThe partial rebreather mask is often use when needing higher FIO2 in place of the nasal cannula to maintain a patient’s SpO2 > 90%.

The partial rebreather mask delivers a moderate concentration of oxygen. (approximately 60 - 80%)

Run the flowmeter at 8 - 15 lpm to ensure the reservoir bag does not deflate on inspiration to prevent CO2 buildup in the mask. Keep reservoir bag above patient’s blanket and make sure it is not twisted or kinked.

Do not block intake ports. Provide alternate source of oxygen (nasal cannula) when patient is eating. Change mask whenever foreign material accumulates on the mask.

Approximately60-80% FIO2

No valves!

Non-Rebreather MaskThe non-rebreather mask administers high concentrations of oxygen (approximately 80 - 100%)

The non-rebreather is used for the patient without an artificial airway (ETT or tracheostomy), exhibiting severe respiratory distress or requiring increased O2 to keep SpO2 > 90%.

Run the flowmeter at 8 - 15 lpm to ensure the reservoir bag does not deflate on inspiration to prevent CO2 accumulation in the face mask. Keep reservoir bag free from patient blanket and make sure it is not twisted or kinked.

Do not block intake port one-way valves. Change mask whenever foreign material accumulates in the mask.

Approximately80-100% FIO2

Notice the 1-way valves!

Aerosol Devices

Aerosol devices administer specific FIO2 concentrations (ranging from 28 to 100%, depending on dial setting)

To provide an increased level of humidity at controlled oxygen concentrations.

Liter flow is determined by the FIO2 dial setting

Oxygen CylinderRemember !

• Cylinders must always be in appropriate carrier or cart, never left standing alone

• Do not use if the cylinder gauge reads less than 500 psi

• Return patient to flow meter on wall when transport is completed

Airway Management

The most common airway emergency is soft tissue upper airway obstruction. Complete upper airway obstruction is accompanied by marked inspiratory efforts without air movement.The first maneuver attempted should be the head-tilt, chin-lift maneuver.

Blocked airway

Oropharyngeal AirwayThe oropharyngeal (oral) airway is designed for insertion along the tongue until the teeth or gingiva limit the insertion. The device lies between the posterior pharynx and the root of the tongue and thereby maintains a patent airway.The oral airway is adequate for comatose patients only and usually for limited periods of time

Measurement of proper size Mouth to jaw line

Nasopharyngeal AirwayThe nasopharyngeal (nasal) airway is a soft/pliable tube constructed so that it can be inserted through one of the nares and follow the posterior wall curvature of the nasopharynx and oropharynx.

It is much better tolerated than the oropharyngel by the semicomatose and awake patient.

Suctioning of the pharynx is possible with appropriately lubricated suction catheter.

Sizing: Nose to ear lobe

Manual Resuscitator

• Delivers high oxygen concentrations (90-100% FiO2)

• Run oxygen flowmeter > 15 lpm• Position head with chin-lift/ head-tilt• Oral airway may be used• Position mask with narrow end over

the bridge of the patient’s nose, ensuring tight seal One-person

Two-person

DefinitionsPulse Oximetry: measuring the estimated arterial oxygen saturation using a non-invasive method.

SpO2: abbreviation for the estimated arterial oxygen saturation given as a percentage, via pulse oximetry.

SaO2: abbreviation for the estimated arterial oxygen saturation given as a percentage, via arterial blood gas.

Hypoxia: an abnormal condition in which the oxygen available to the body cells are inadequate to meet their metabolic needs

Hypoxemia: abnormal deficiency of oxygen in the arterial blood.

How Do Pulse Oximeter’s work?

Red and infrared light must pass through a perfused capillary bed of the finger, toe, ear lobe,

neonate’s foot or hand.The light emitters must be positioned directly

opposite of the photodector.The oximeter uses the ratio of Red / Infrared light

that is absorbed by the hemoglobin to determine the oxygen saturation (Spo2).

Indications

• daily monitoring • titration of supplemental oxygen.• special procedures (i.e. bronchoscopy, TEE,

conscious sedation).• sleep studies.• ambulation

To determine adequacy of oxygenation during

Clinical signs of hypoxia

• Tachycardia• Arrhythmias• Tachypnea• Dyspnea• Restlessness• Cyanosis• Irritability• Decreased LOC

Pulse oximetry

• Non-invasive• Easy to use• Can be used

continuously to monitor trends.

• Rapid response• Inexpensive

• Must have good signal to be accurate

• Inaccurate under certain circumstances.

• Pressure sores/ burns from prolonged use.

DisadvantagesAdvantages

pH The relative concentration of

hydrogen ion in arterial blood. The chief component of acid-

base balance.

(acidosis) 7.35 7.40 7.45 (alkalosis)“base”

pCO2 (alkalosis) 35 40 45 (acidosis)

PaCO2

PaCO2 is the partial pressure of carbon dioxide in the blood

CO2 functions as a RESPIRATORY acid

Normal value is 40 mmHg CO2 levels stimulate respiration

“base”

PaO2

Partial pressure of oxygen in arterial blood Does not play an active role in acid/base balance Normal for an adult < 60 years is 80-100 mmHg

After the age of 60, normal PaO2 levels are slightly lower due to decreasing lung compliance

Levels of Hypoxia

Norm80-100mmHg

Mild60-80mmHg

Moderate40-60mmHg

Severe<40mmHg

Hypoxemia/ Hypoxia

Hypoxemia: Low oxygen content in arterial blood (seen on ABG)

Hypoxia: Inadequate oxygen at the tissue or cellular level (clinical judgment)

Clinical signs of hypoxemia – tachycardia– cyanosis– hyperventilation– restlessness, uncoordinated activities– hypertension

Bicarbonate (HCO3)

An indicator of the base reserve Reflects the kidney and/ or METABOLIC function

HCO3 (acidosis) 22 24 26 (alkalosis)“base”

Oxygen Saturation (SaO2)

Percent of hemoglobin which is bound to oxygen (calculated)

Normal SaO2 is 95 - 100%

ABG Normal Values

pH 7.35 7.40 7.45 pCO2 35 40 45 pO2 > 80 mmHg

HCO3 22 24 26 BE -2 0 +2

low end normal high end

acidic

alkalotic

acidic

acidic

alkalotic

alkalotic

alkalotic

acidic

Assess Acid/ base balance (step 1)

pH 7.33

PaCO2 64

HCO3 23

PaO2 65

Look at the pH9 is it normal (N)?9 is it acidotic (A)?9 is it a base (alkalotic) (B)?

“A”

Look at the pCO29 is it normal (N)?9 is it acidotic (A)?9 is it a base (alkalotic) (B)?

“A”

“N” Look at the HCO3

9 is it normal (N)?9 is it acidotic (A)?9 is it a base (alkalotic) (B)?

Match system to pH (step #2)

pH 7.33

PaCO2 64

HCO3 23

PaO2 65

“A”

“A”

“N”

The acidosis is caused by the RESPIRATORY acidsSo this example is a Respiratory Acidosis

Acidosis

Acidosis

Normal

pH 7.33

PaCO2 41

HCO3 12

PaO2 65

“N” Normal

“A” Acidosis

The acidosis is caused by the METABOLIC acidsSo this example is a Metabolic Acidosis

“A” Acidosis

Another Example

Chronic CO2 retention COPD patients with chronic CO2 retention no longer breathe

according to CO2 levels.

These patients rely on the presence of hypoxemia (low PaO2) to stimulate respiration.

• Avoid giving too much O2 to these patients. Elevated oxygen levels may reduce their stimulation to breathe!• Keep PaO2 between 50 - 60 (pulse-ox 85 - 90%).

Baseline PaCO2 > 45 mmHg.

Elevated HCO3 (to compensate for increased PaCO2) Baseline pH within normal limits.

Typical Baseline COPD: CO2 Retainer

ABG’s on Room Air

pH 7.40

PaCO2 50

HCO3 32

PaO2 55

“N”

“A”

“B”

Compensated Respiratory Acidosis with moderate hypoxia

Moderate hypoxemia

Retractions

• Intercostal

• Suprasternal

• Clavicular

• Substernal

• Subcostal

Admitting the Pediatric PatientAssessment of the Respiratory System

Admitting the Pediatric PatientAssessment of the Respiratory System

– Respiratory Rate/Pattern

• Do not rely on monitor to obtain accurate RR

• Count for 1 full minute

• Observe pattern (periods of apnea, paradoxical, rapid and deep)

– Breath Sounds…Can be very tricky!

• The infant or toddler will not remain motionless or quiet.

• The infant or toddler will not take a deep breath upon command.

• The room may be noisy.

• The child or infant may become frightened and begin crying.

• Listen during Insp. and Exp. Phase (2 cycles ideal)

• Systematic Assessment; comparing segments from side to side

Pulmonary Disorders in ChildrenCase #1

3 month old infant presents to pediatrics with:

– Hr 120-140– SpO2 85%– RR 60 bpm– Insp/Exp. Wheezing– Inspiratory Crackles– Paroxysmal cough– Parents report periods of apnea– Copious thick secretions– Intercostal & Suprasternal Retractions– Rhinitis– Afebrile– Normal WBC

Crackles

Wheezes

Pulmonary Disorders in Children

• CXR: Air trapping, atelectasis and infiltrates.

Pulmonary Disorders in ChildrenBronchiolitis

• Management– Oxygen– Suction– IV hydration– Racemic Epinephrine Nebs– Bronchodilators– Antibiotics– Monitoring– Bronchiolitis Protocol (if

ordered)

Pulmonary Disorders in ChildrenCase #2

• 10 month old presents to the ED. Mom states when she picked her son up from the daycare after work he was breathing harder and had trouble drinking his bottle. MD office sent her home with rx. For MDI and oral steroid. Mom states she is very worried; feels something is very wrong.

-- HR 180 -- Suprasternal retractions– RR 80 -- SpO2 90% on 5 lpm HFH-- Frequent Coughing -- Nasal Flaring-- Febrile -- WBC increased-- Grunting -- RUL atelectasis– Tight exp. wheezing despite 1 hour continuous neb.

Case #2Foreign Body Aspiration

• Bronchoscopy revealed a small acorn in the Rt. Mainstem Bronchus.

• Foreign Body removed; infant WOB improved dramatically.

• Was sent home on antibiotics.

Pulmonary Disorders in ChildrenCase #3

• 10 year old presents to the ER with the following symptoms after returning from camping:

– Coughing (night), Sneezing

– Fatigue (poor sleep, unable to perform usual activities)

– Increased WOB (tachypnea, retractions, nasal flaring, tripod position)

– Wheezing

– CXR with hyper inflated lungs and flattened diaphragms

Pulmonary Disorders in ChildrenAsthma

Treatment– Oxygen– Nebs: Intermittent/Continuous (Mask vs. Blow-by)

• Consider Peak Flows before and after tx.– Steroid Administration– IV Hydration– Frequent reassessment by RN/RT– Volume expansion

• Walk, blow bubbles, sing songs– Rest

• Allow child to assume position of comfort

Pulmonary Disorders in ChildrenCase #4

• Tripoding• Grunting• Substernal Retractions• Nasal Flaring• Hypoxemia (no reserve)• Bradycardia• Paroxysmal cough (can be life

threatening)• RR 60 decreases to 24• Paradoxical/Seesaw breathing

pattern• Decreased LOC

Pulmonary Disorders in ChildrenCase #4

• Impending Respiratory Failure– Immediate emergency action must be taken• Rapid Response Team

Call NICU charge Nurse for kids under the age of 12.