Respiration Under Stress

Concentration, higher, solubility, lower

Partial pressure is proportional to concentration / solubility

• Higher __, __ (higher/lower) partial pressure

• Higher __, __ (higher/lower) partial pressure

Barometric pressure

Pressure generated by column of air as tall as atmosphere

cm of H2O

Dalton’s Law of Partial Pressures and FIO2

• With lung air pressure, units are __ __ __

barometric pressure x fractional concentration

Partial pressure of each gas =

21, 78, 760

• FIO2 = 160 mmHg (__% of dry air)

• FIN2 = 590 mmHg (__% of dry air)

• FI Air = __ mmHg at sea level

21, 78, 47, 713

• PIO2 = 150 mm Hg (__% of dry air)

• PIN2 = 556 mm Hg (__% of dry air)

• PIH2O = __ mmHg (humidified air)

• PI Air = __ mm Hg at sea level

PIO2 - (PaCO2/R)

PAO2 =

R, 0.8

__ is metabolic relationship between O2 consumption and CO2 production ~ __ (value)

PAO2 - PaO2

A-a gradient =

10-20 (mm Hg)

A-a gradient Normal range

Perfusion, deadspace, ventilation, PE

V / (Q of 0)  = infinity

• No __ = __

• “Wasted __”

• Ex: Trachea and bronchi, and __ (condition)

Ventilation, shunt, perfusion, pulmonary artery, right to left

(V of 0) / Q = 0

• No __ = __

• “Wasted __”

  • No passage to the __ __ (circulation), means stays deoxygenated

• Ex: Intrapulmonary and __ to __ cardiac shunts

Low

Ideal V/Q ratio = __ perfusion relative to ventilation or vice versa

Hypoxia

Tissue O2 delivery or utilization < tissue O2 demand

Inadequate O2 delivery

Factor of hypoxia from:

• Low arterial O2 content/availability/blood flow

Increased tissue O2 demand

Factor of hypoxia from:

• Fever, malignant hyperthermia

Impaired tissue O2 utilization

Factor of hypoxia from:

• Cyanide toxicity

Hypoxemia

Factor of inadequate O2 delivery in hypoxia:

• PaO2 < 60 mmHg or sat < 90%

Anemia

Factor of inadequate O2 delivery in hypoxia:

• Low Hgb

Carbon monoxide poisoning

Factor of inadequate O2 delivery in hypoxia:

• Reduced Hb-O2 and impaired unloading

Low cardiac output

Factor of inadequate O2 delivery in hypoxia:

• Ex: MI, CHF, cardiac arrest

60, 90

In hypoxemia:

• PaO2 < __ mmHg

• O2 sat < __ %

High and normal A-a gradient

(2) outcomes of low PaO2

Shunt

High A-a gradient that doesn’t correct

Other V/Q mismatch

High A-a gradient that improves substantially; normal DLCO

Diffusion impairment

High A-a gradient that improves substantially; low DLCO

Hypoventilation

Normal A-a gradient with high PCO2

Low PIO2

Normal A-a gradient with normal to low PCO2

Diffusion capacity, V/Q, pulmonary vascular

Exercise

• Increased __ __ (in moderate exercise)

• Capillary recruitment and distension

  • Improved __ matching

  • Lower __ __ resistance

Minute ventilation, PAO2, shortens

__ __ increases >> cardiac output increases

• Maintains very high __ (measure) to maximally load up as alveolar-capillary transit time __ (shortens/lengthens)

PCO2, H+, temp, 1

Right shift of oxygen-hemoglobin dissociation curve

• Increased (3) variables

• Metabolism shifts and respiratory quotient R moves from 0.8 → _

Bodies, CO2, polycythemia, constriction, RV

Hypoxemia at high altitude

• Hyperventilation - from carotid __, maintains O2 in lungs and reduces __

• __ (condition in blood)

• Pulmonary vaso__ → Increased pulmonary resistance and __ (heart region) pressures

Polycythemia

Buildup of erythropoietin increases total O2 content

Low, uniform, V/Q mismatch

Space

• __ gravity causes more __ blood distribution in pulmonary vessels

  • Reduces normal __ __ across lung zones

1, 10, lung compression, transmural

Dive

• Pressure increases _ atm (760 mmHg) every __ meters

  • Scuba tank delivers pressurized air to counterbalance __ __ (bad) and keep __ pressures stable

Exhale, expansion, decreases, pneumothorax, blood, fat, rapid

Boyle’s Law in Diving

• Divers must __ when surfacing due to gas __ in lung as pressure __ (increases/decreases) → lead to __ (condition)

• High amounts of N2 gas dissolve in __ and __ under high pressures

  • Bends - Precipitate out as bubbles during __ surfacing

FIO2, +, pressurized, alveolar ventilation, O2

Respiratory Support - Controllable Variables

• 1. __ is easy to influence

• 2. Barometric pressure can be manipulated by increasing _ pressure of delivered air or putting patient in __ space

• 3. PaCO2 can be manipulated by increasing __ __ // bringing in more __

(Standard )nasal cannula

up to 6 L/min; FIO2 max of approximately 40%

Simple mask

up to 5-10 L/min; FIO2 max of approximately 30-70%

Non-rebreather mask

up to 5-15 L/min; FIO2 max of approximately 100%

40, 30-70, 100

• Nasal canula FIO2 max = __

• Simple mask FIO2 max = __

• Non-rebreather FIO2 max = __

Reservoir bag, hypoxemia

Non-rebreather mask

• __ __ must be inflated

• Usually reserved for significant __ not correct with other 2 methods

Continuous positive airway pressure, negative

CPAP = __ __ __ __

• Patient drawing air in with __ pressure as well

Bilevel positive airway pressure, -, respirations, +, spontaneous

BiPAP = __ __ __ __

• BiPAP responds to initial __ (+/-) pressure generated by normal __ and adds __ (+/-) pressure to assist with a __ breath

Hemodynamic, aspiration, uncooperative, hypoxemia, facial, pneumothorax

Contraindications of Non-Invasive Positive Pressure Ventilation

• __ instability (blood)

• __ risk (airway)

• __ patient or altered MS

• Severe __ (blood)

• Significant __ trauma

• Untreated __ (resp)

Invasive Positive Pressure Ventilation (IPPV)

Intubation

CPAP, BiPAP, pushes, low compliance, barotrauma, set, independent, tighter, minute

PPP

• Includes __ and __

• __ (pushes/pulls) air into lungs

• Able to overcome __ __, but potential __ due to overinflation

• __ PEEP (to minimize atelectasis) and FIO2

• __ of patient energy/strength

• __ control of volumes and pressures and __ ventilation

Pull, low compliance, limit, minimal, required, regulating, minute

Normal ventilation

• __ (pull/push) air into lungs

• Limited ability to overcome __ __ problems, and __ potential harm of overinflation

• __ PEEP and variable FIO2

• Patient energy __

• Body is very good when healthy at __ volumes, pressures, and __ ventilation

anatomic deadspace

A non-rebreather can provide better oxygenation than a simple mask by reducing…