Lesson 2 Oxygenation

Pulse oximetry range

90%-100%

SpO2

Peripheral arterial oxyhemoglobin saturation; expressed as a percentage

Pulse oximetry uses

Monitoring patients receiving oxygen or at risk for hypoxemia

Pulse oximetry limitations

Less accurate when SpO2 ≤ 80%; does NOT replace need for ABG; low hemoglobin affects accuracy

Room air (RA) oxygen percentage

21%

Oxygen as medication

O2 is a medication and must be ordered by HCP; in emergency or clear clinical indication can administer and get order later

Nasal cannula flow rate

1-6 L/min

Nasal cannula FiO2

25-40% (~4%/L of flow)

Face mask flow rate

5-10 L/min

Face mask FiO2

40-60%

Face tent flow rate

10-15 L/min

Face tent FiO2

~40%

Venturi mask flow rate

2-15 L/min (based on valve)

Venturi mask FiO2

24-60% (precisely controlled)

Non-rebreather flow rate

12-15 L/min

Non-rebreather FiO2

80-95%

High flow nasal cannula flow rate

Up to 60 L/min

High flow nasal cannula FiO2

21-100%

Oxygen therapy goal SpO2

>90%

Two central drivers of respiration

Hypoxemia (low O2 in blood) and hypercarbia (high CO2 in blood)

COPD patients respiratory drive

Live chronically hypercarbic; main trigger for breathing is level of O2

COPD patient target SpO2

88-92%

COPD patient oxygen delivery devices

Can only use nasal cannula or venturi mask

Rule of 4s for nasal cannula

1L/min=24%, 2L/min=28%, 3L/min=32%, 4L/min=36%, 5L/min=40%, 6L/min=44%

Nasal cannula prong direction

Curved towards the back of the pharynx

Nasal cannula disadvantages

Can be dislodged easily; low-flow rates can cause dryness of nasal mucosa

Humidified oxygen uses

For high-flow O2 rates; uses distilled or sterile water

Humidified oxygen purpose

Liquifies secretions, hydrates mucous

Humidified oxygen precautions

Use caution in patients with fluid restrictions such as CHF; do not use in low-flow states (4-6L/min or less)

Simple mask flow rate

5-8 L/min (low flow)

Simple mask FiO2

40-60%

Simple mask considerations

Assess for claustrophobia; secure order to replace with NC during meal time; assess skin integrity

Venturi mask delivery precision

Delivers the most precise concentration of O2

Venturi mask monitoring

Requires careful monitoring to verify O2 at flow rate ordered; assess that air intake valves are not blocked

Venturi mask ordering

Order is in liters flow and % of oxygen; color coded

Partial rebreather mask flow rate

10-15 L/min

Partial rebreather mask FiO2

50-75%

Partial rebreather mask mechanism

Face mask with reservoir to collect exhaled air; remaining exhaled air exits through vents; air in reservoir mixed with 100% O2 for next inhalation; conserves O2

Non-rebreather mask flow rate

10-15 L/min

Non-rebreather mask FiO2

80-95%

Non-rebreather mask mechanism

One-way valves prevent patient from rebreathing exhaled air; reservoir filled with O2 that enters mask on inspiration; exhaled air escapes through side vents

Oxygen safety - combustibility

O2 is combustible!

Oxygen safety checks

Check flow rate regularly (part of general survey); check water level in reservoir for humidified oxygen (filled to line and gently bubbling)

Nebulizer treatment use

Disperses fine particles of liquid medication into respiratory tract; delivers inhaled medications such as bronchodilators

Nebulizer treatment duration

Continues until all medication has been aerosolized (~15 mins)

Nebulizer teaching

Must be cleaned after use

Nebulizer nursing considerations

Assess/reassess lung sounds, O2 saturation, and respirations before and after treatment

Metered dose inhaler (MDI) use

Delivers controlled dose of medication with each compression

MDI medication types

Bronchodilators, mucolytic agents, corticosteroids

MDI post-administration care

Rinse mouth after certain medications such as corticosteroids to prevent oral thrush; always reassess and document response

MDI spacer purpose

Aerochamber improves medication delivery

Common MDI mistakes

Failing to shake canister, holding inhaler upside down, inhaling through nose rather than mouth, inhaling too rapidly, stopping inhalation too early, failing to hold breath after inhalation, inhaling two sprays with one breath

MDI technique - breath hold

Hold breath for 5-10 seconds or as long as possible after inhalation

MDI technique - wait time

Wait 1-5 minutes as indicated by medication before administering next puff

Dry powder inhaler (DPI) mechanism

Small capsule or disc inserted into DPI and made into powder; flow activated by patient breath

DPI patient requirement

Patient must be able to take powerful inspiration for adequate drug inhalation

DPI breathing technique

Breathe in strong, steady, and deeply through mouth for longer than 2-3 seconds

DPI nursing pearl

Do not breathe into DPI or moisture from mouth will make medication sticky and not inhalable

DPI breath hold

Hold breath for 5-10 seconds or as long as possible after inhalation

Hydration for respiratory health

Maintain fluidity of secretions; thick secretions can cause airway resistance; drink 1.9-2.9 L/day unless have heart failure/fluid overload

Position changes for respiratory health

High-fowlers to increase respiratory excursion via gravity; shifts mucus preventing pooling

Progressive ambulation benefits

Promotes peristalsis which helps breathing; uses gravity to expand thorax/increase depth of breaths; increases circulation

Deep breathing purpose

Overcome hypoventilation such as during bedrest or post-operatively

Deep breathing technique

In through nose, out through mouth; "smell flowers, blow out candle"

Deep breathing frequency

3-4 times/day, 10 breaths per set

Pursed-lip breathing purpose

Prolong exhalation by creating smaller opening for air movement; helps feelings of dyspnea or panic

Diaphragmatic breathing benefits

Reduces respiratory rate, increases alveolar ventilation, promotes effective expiration

Diaphragmatic breathing technique

One hand on abdomen and one on chest; breathe in letting abdomen protrude; breathe out through pursed lips while contracting abdomen muscles; do for 1 min then rest for 2 min

Diaphragmatic breathing patient population

Helpful for patients with COPD; breathe more with abdomen as opposed to chest

Incentive spirometry purpose

Provides visual reinforcement for deep breathing; encourages slow and deep breaths; promotes optimal gas exchange and secretion expectoration

Incentive spirometry measurement

Measures maximal inhalation in mL

Incentive spirometry use timing

Often used post-operatively

Incentive spirometry capacity

Normal average capacity based on sex, age, and height

Coughing function

Cleansing mechanism; works to keep airway clear of secretions/debris

Voluntary coughing

Promotes airway clearance (pre and postoperatively important); paired with deep breathing

Cough pillow

Used to splint over chest or abdominal incisions because coughing can be painful

Chest physiotherapy (CPT) purpose

Mobilizes/loosens secretions to increase mucus clearance

CPT techniques

Includes percussion, vibration, and postural drainage

CPT contraindications

Not recommended in pediatric pneumonia, adults with COPD, or post-operatively

CPT common use

Used a lot in patients with Cystic Fibrosis (CF)

CPT provider

Performed by respiratory therapists

Postural drainage semi-reclined sitting

Patient seated in chair leaning back at ~45-degree angle; drainage moving upward from chest

Postural drainage prone position

Patient lying flat on stomach with pillow under hips/pelvis; drainage moving downward from upper back/chest toward head

Postural drainage supine position

Patient lying flat on back with pillow under upper back/shoulders; drainage moving downward from upper chest

Postural drainage purpose

Uses gravity to help drain mucus and secretions from different lung segments

Sputum culture methods

Suctioned or coughed up

Sputum culture laboratory tests

Gram stain, culture and sensitivity