Adult 2 Unit 1

Arterial Blood Gases (ABG)

• Blood Ph    7.35 - 7.45

• PaC0₂ or C0₂   35 - 45 mm Hg

• HCo₃    22 - 26 mm Hg

• Sa02   95-100% (saturation of hemoglobin with oxygen)

• Pa02   75 - 100 (partial pressure of oxygen in arterial blood)

Acid - Base

It's all about H+ (hydrogen) ions

Acids release H+ ions

Bases accept H+ ions

Increased H+ ions = decreased pH = acidosis

Decreased H+ ions - increased pH = alkalosis

Acid-base balance occurs when there is homestasis of H+ ion concentrations

What 2 systems regulate acid-base balance in the body?

CO2 - Lungs

HCO3 - Kidneys

Carbonic Acid-Bicarbonate System

• Lungs and kidneys help regulate blood pH

• Process known as Compensation

• Lungs

  • Respond within minutes

  • Respinse cannot be maintained indefinitely

• Kidneys

  • Hours to days to compensate

  • Response maintained for longer

Reaching Homeostasis

• When the body senses a change in CO_2, a signal is sent to the brain to alter the rate & depth of respirations

  • Too much CO₂ means the rate of respirations will be INCREASED to blow off excess C0₂

    • Increases pH

  • Too little C0₂ means the rate of respirations will be DECREASED to hold onto C0₂ & bring it back to normal levels

    • Decreases pH

• Kidneys control the movement of bicarbonate in the bloodstream & urine

Where does an ABG sample come from?

Specially trained nurses can obtain an ABG from an arterial stick.

The most common site is the radial artery.

The patient may have an invasive catheter inserted into an artery (arterial line).

Blood samples may be obtained from this line also.

Interpreting ABG's

1. Look at the pH

    a. Is it low? = acidosis

    b. Is it high? = alkalosis

2. Look at the PaCo2 (CO2)

    a. Is it low? = alkalosis

    b. Is it high? = acidosis

3. Look at the HC03

    a. Is it low? = acidosis

    b. Is it high? = alkalosis

4. What is the primary issue? Respiratory or metabolic?

Interpret the following ABG:

pH 7.28, PaC02 67, HC03 24

Respiratory Acidosis

Interpret the ABG: 

pH 7.49, PaC02 35, HC03 50

Metabolic Alkalosis

Interpret the ABG:

Ph 7.32, PaC02 35, HC03 20

Metabolic Acidosis

What about the Pa02?

To interpret an ABG, you do not necessarily look at the Pa02. It does not interfer with acidosi/alkalosis. It is a measure of the patient's oxygenation. If the Pa02 is low, you need to increase the oxygenation. If the Pa02 is high, you need to decrease the oxygenation. 

 

For Example, a patient's ABG is: pH 7.24, Pa02 50, PaC02 70, HC03 22. To interpret this ABG, you know that the pH is low and the PaC02 is high so the patient is in respiratory acidosis. You also note that the Pa02 is low, so you need to increase their oxygenation. 

 

As the nurse, you would accomplish 2 things: increase oxygenation and increase respirations to blow off C02. 

Acute Respiratory Failure (ARF)

What it is

• Deterioration of gas exchange function 

  • Impaired function of CNS 

  • Neuromuscular dysfunction

  • Musculoskeletal dysfunction 

  • Pulmonary dysfunction 

  • Surgery 

Acute Respiratory Failure (ARF)

Clinical manifestations: 

• Early Signs:

  • Impaired oxygenation

  • Restlessness

  • Fatigue

  • Headache

  • Dyspnea

  • Air hunger

  • Tachycardia

  • Increased blood pressure.

• As the hypoxemia progresses:

  • Confusion

  • Lethargy

  • Tachycardia

  • Tachypnea

  • Central cyanosis

  • Diaphoresis

  • Respiratory arrest.

Acute Respiratory Failure (ARF)

Physical manifestations:

Use of accessory muscles

Decreased breath sounds if the patient cannot adequately ventilate

Oher findings related specifically to the underlying disease process and cause of acute respiratory failure.

Acute Respiratory Failure (ARF)

Ranges

PaO2 < 60 mmHg

PaCO2 > 50 mmHg

pH < 7.35

Acute Respiratory Failure (ARF)

Management

• Treat underlying cause & restore adequate gas exchange

• ET intubation & mechanical ventilation

• Monitor respiratory status: LOC, ABGs, pulse ox, VS, work of breathing

• Prevent complications Turning q2 hours (cough & deep breath if possible), mouth care, skin care, passive ROM

• Communication

Acute Respiratory Failure (ARF)

Diagnostics

• ABGs

• ECG 

• Cultures 

• Chest X-ray

• CT

• Bronchoscopy 

• Thoracentesis 

• Pulmonary function tests

Acute Respiratory Failure (ARF)

Overall effect

Cause is not corrected → Failure Worsens → Increase work of breathing →Muscle/body fatigues → Failure & Arrest

Acute Respiratory Distress Syndrome (ARDS)

Basics

Spectrum of mild – severe

Diffuse alveolar damage

Pulmonary edema

Ventilation/perfusion mismatches

Acute Respiratory Distress Syndrome (ARDS)

Risk Factors:

• Aspiration (gastric secretions, drowning, hydrocarbons)

• COVID-19 pneumonia

• Drug ingestion and overdose

• E-cigarettes or vaping (i.e., e-cigarette or vaping product-associated acute lung injury [EVALI])

• Fat or air embolism

• Hematologic disorders (disseminated intravascular coagulation, massive transfusions, cardiopulmonary bypass)

• Localized infection (bacterial, fungal, viral pneumonia)

• Major surgery

• Metabolic disorders (pancreatitis, uremia)

• Prolonged inhalation of high concentrations of oxygen, smoke, or corrosive substances

• Sepsis

• Shock (any cause)

• Trauma (pulmonary contusion, multiple fractures, head injury)

Acute Respiratory Distress Syndrome (ARDS)

Clinical Manifestations

• Dyspnea

• Hypoxemia unresponsive to supplemental oxygen 

• Bilateral infiltrates on x-ray (white lungs on imaging)

• Decreased lung compliance

• Breath sounds: Crackles

• Intercostal retractions

Acute Respiratory Distress Syndrome (ARDS)

Management

• Intubation + mechanical ventilation + PEEP

• Circulatory support:

  • Adequate fluid volume

  • Nutritional support

• Treatment of hypotension

  • Inotropic or vasopressor agents

• Positioning

• Medications 

  • Sedation +/- paralytics

• Emotional support

• Treatment of pain

Pulmonary Embolism

Diagnostics

• Chest x-ray

• EKG

• ABGs

• Multidector-row CT (MDCTA)

• Pulmonary angiography

• V/Q Scan

• D-dimer assay 

Pulmonary Embolism

Management

• Oxygen 

• Medications 

  • Anticoagulants

  • Thrombolytics 

• Surgery 

• Assessment 

• Monitoring

• Prevention 

Pulmonary Embolism

Medications

Anticoagulation Therapy

• Prevention

• Begin immediately

• Examples of medications:

• Monitoring Considerations:

Thrombolytic Therapy

• Clot-busters

• Unstable patients/massive PE

• Examples of medications:

• Monitoring Considerations:

Pulmonary Embolism

IVC Filter

Recurrent PEs

Accessed through groin

Permanent or removable

Pneumothorax

Basics

Air in the pleural cavity resulting in lung collapse

Treatment? Chest Tube

Pneumothorax

Clinical Manifestations

• Sudden pleuritic pain

• Tachypnea & mild distress or uncomplicated pneumothorax

• Lung collapse & acute respiratory distress with large pneumothorax 

  • Anxiety, dyspnea, air hunger, accessory muscle use, central cyanosis

• Hypotension, tachycardia, profuse diaphoresis

• Nursing assessment: Asymmetrical chest wall expansion, diminished breath sounds

Pneumothorax

Chest Tubes

Removes excess air, fluid, and blood

Treatment of Pneumothorax

Collection chamber

Water seal

Suction control

Air-leak monitor

Types of Chest Tubes

Traditional Water Seal (wet suction)	3 chambers (collection chamber, water-seal chamber, wet suction control chamber)	Sterile fluid instilled into water seal & suction chambers Positive & negative pressure release valves Intermittent bubbling indicates system is functioning properly Additional suctioning can be applied
Dry Suction Water Seal (dry suction)	3 chambers (collection chamber, water-seal chamber, suction regulator dial)	Sterile fluid instilled into water seal chamber at 2 cm level No fluid filled suction chamber Suction pressure is set with suction regulator dial Positive & negative pressure release valves Indicator that signifies adequate suction pressure
Dry Suction (one way valve system)	One way mechanical valve that allows air to leave the chest & prevents air from moving back into the chest	No need to fill suction chamber with fluid Works even if knocked over

Chest Tubes

Management 

• Placement of chamber? 

• Drainage and output 

• Air leak / bubbling in water seal chamber 

• Dressing 

• Site 

• Assessment 

• Pain 

• Education 

You walk into the patient's room and notice the wall vacuum suctioning is turned off. What do you do?

Turn it back on & Assess patient

You walk into your patient's room and notice the chest tube has become disconnected from the drainage system tubing. What do you do?

Clamp it short term

Reconnect it after rreplacing system and chamber

You walk into your patient's room and notice they have pulled their chest tube out. What do you do? 

Cover hole with sterile gauze

Tape 3 sides but leave 1 side open to create a vent

Call provider

Pleural Effusion

• Collection of fluid in pleural space (5 - 15 mL is normal)

• Fluid may be clear, bloody or purulent

• Causes: heart failure, TB, pneumonia, 

    Infection, tumors

• Clinical manifestations: 

  • Underlying cause

  • Severity of effusion

  • Physical assessment: Cracles in lung sounds ________

• Management: thoracentesis or chest tube

Artificial Airways 

• Endotracheal tubes

  • Placement of a tube into the trachea

  • Oral

  • Nasal

  • Time frame:

• Tracheostomy

  • Long-term ventilation

Intubation

Basics

• Process of placing an endotracheal tube to provide a patent airway

• Preparation, sedation, paralysis

• Nursing Role:

  • Gather supplies/equipment

  • Administer medications

  • Monitor VS

Intubation

Medications 

• Sedation for rapid sequence intubation

  • Fentanyl

  • Midazolam

  • Etomidate

  • Ketamine

  • Propofol

• Paralytics

  • Succinylcholine

  • Cistracurium besylate

  • Rocuronium

  • Vecuronium

Post-Intubation care

Respiratory assessment

ETT placement

Oxygenation

Medications 

Restraints

Right after intubation, the physician asks you to listen to breath sounds to confirm placement. You hear breath sounds on the right side but not the left. What do you do? 

Right after intubation you see abdominal movement and distention with each breath. What do you do? 

Care of the patient with an ETT 

• Maintain tube 

• Manage secretions 

• Oral care 

• Skin integrity

• Foster communication and comfort

• Prevent complications 

Suctioning

• In-line (closed) suction catheter/Ballard

  • Sustains PEEP

• Pre-oxygenate before and after

• Complications:

  • Bronchospasms

  • Trauma

Complications from intubation

Respiratory

Cardiac

Trauma

Infection

Tracheal Damage

Mechanical ventilators

• Positive pressure breathing device

• Non-invasive and invasive

• Indications for mechanical ventilation:

  • Laboratory Values:

  • Clinical manifestations

Noninvasive positive-pressure ventilation

Basics

• Given via facemasks

• Decrease the work of breathing

• Decreases risk of nosocomial infections

• Best mode: pressure-controlled with pressure-support

• Indications:

• Contraindications:

Noninvasive positive-pressure ventilation

CPAP vs BIPAP

• CPAP (Continuous Positive Airway Pressure)

  • Single positive pressure to airways during respiratory cycle

  • Used with mechanical ventilation or leak-proof mask

  • Obstructive sleep apnea

• BIPAP (Bilevel Positive Airway Pressure)

  • Pressure during inspiratory and expiratory

  • Oxygenation and ventilation

  • Back-up rate

  • Most common uses: severe COPD & sleep apnea

PEEP

• Positive pressure at the end of exhalation to keep alveoli open

• Maintains recruitment

• Improves oxygenation

• *The higher the PEEP, the greater the risk for acute lung injury and __________________________

Ventilator modes

Controlled Modes (CMV)	Support Modes	Combination Modes:
Pressure Control	Pressure Support/CPAP	SIMV
Volume Control

PRESSURE CONTROL


CONTINUOUS MANDATORY VENTILATION

Set pressure

Set respiratory rate

Tidal volume varies

Volume control


Continuous Mandatory ventilation

• Preset tidal volume

• Preset respiratory rate

• Pressure varies

• Tidal volume is based off patient’s ideal body weight

  • 6-10 mL/kg