Acute Resp Failure

Question 1

hypoxemic RF due to?

Answer 1

inadequate oxygen delivery

Question 2

hypercapnic RF due to?

Answer 2

respiratory acidosis

Question 3

name 5 causes of hypoxemic failure

Answer 3

decreased PIO2 (altitude, plane), decreased alveolar ventilation, VQ mismatch, R to L shunt, diffusion limitation

Question 4

decreased alveolar ventilation has what effect on PACO2 and PAO2

Answer 4

increases PACO2, decreases PAO2

Question 5

acute hypercapnea from drug overdose causes an increased PACO2, resulting in?

Answer 5

decreased PAO2

Question 6

what effect does oxygen therapy have on dead space

Answer 6

no effects

Question 7

the only physiological cause of oxygen diffusion limitation is?

Answer 7

exercise (due to fast blood flow and insufficient time for diffusion)

Question 8

three ways to increase PaCO2 (hypercapnia)

Answer 8

increase VACO2, decrease minute ventilation, increase dead space

Question 9

name two situations where you have an increased VACO2

Answer 9

fever, trauma

Question 10

name two situations where you have an increased dead space

Answer 10

PE, emphysema

Question 11

what are some common causes of decreased minute ventilation?

Answer 11

drug overdose (decreased resp drive), nerve conduction abnormalities, neuromusc dz, chest wall abnormalities, lung disease, upper airway obstruction

Question 12

a high pCO2, low pH, and normal bicarb indicate?

Answer 12

acute failure (resp acidosis)

Question 13

a high pCO2, close to normal pH, and high bicarb indicate?

Answer 13

compensated failure (chronic retention of CO2 such as in COPD)

Question 14

a super high pCO2, low pH, and high bicarb

Answer 14

acute AND chronic failure

Question 15

be careful giving oxygen to someone with high CO2 retention because?

Answer 15

they have changed their set point (carotid body receptors for O2) and oxygen therapy can cause them to stop breathing – give them a lower dose

Question 16

late stage respiratory failure from muscle weakness can present with?

Answer 16

hypercapnea

Question 17

signs of resp mm weakness

Answer 17

tachypnea, decreased vital capacity, decreased inspiratory force, ineffective cough

Question 18

treat resp mm weakness with?

Answer 18

support ventilation

Question 19

treatment for hypercapnic failure:

Answer 19

1. underlying cause, 2. resp stimulants, 3. assist devices, 4. tracheal intubation & PP ventilation, 5. mechanical ventilation

Question 20

name 2 current types of assist devices

Answer 20

nasal/face CPAP (cont positive airway pressure), BiPAP (pressure in and out)

Question 21

4 ventilatory controls

Answer 21

1. breath initiation/RR, 2. tidal vol/pressure, 3. patient reg’n, 4. PEEP (a little air to prevent collapse)

Question 22

how does PEEP affect FRC?

Answer 22

it is increased

Question 23

adverse effects of PEEP

Answer 23

barotrauma from increased intrathoracic pressure –> decreased venous return –> decreased cardiac output

Question 24

low pH, low CO2, and low bicarb sign of?

Answer 24

metabolic acidosis!