312-UNIT TWO EXAM

Question 1

List the indications for Oxygen therapy

Answer 1

1. Correct documented or suspected acute HYPOXEMIA
2. Decrease the symptoms associated with CHRONIC HYPOXEMIA
3. Decrease the workload hypoxemia imposes on the cardiopulmonary system

Question 2

Describe how to monitor Oxygen therapy

Answer 2

Check Vitals (temp, HR, RR, BP), Perform ABG, Pulse-Ox meter, Use Oxygen analyzers for delivery devices.

Question 3

Calculate total flow being delivered from mask.

Answer 3

100-FiO2/FiO2-21=Air:O2 (air:O2XLiterflow)

Question 4

Know when to reduce use of oxygen (hours, days, weeks)

Answer 4

Limit patient exposure to 100% Oxygen to less than 24 hours whenever possible.

High FiO2 is acceptable if the concentration can be decreased to 70% within 2 days and 50% or less in 5 days.

Question 5

Define Oxygen Induced Hypoventilation.

Answer 5

Complication of Oxygen Therapy–PaO2 greater than 60 mmHg may depress ventilation in some patients with chronic hypercapnia (CO2 retainers)

Question 6

Explain the cause of oxygen toxicity.

Answer 6

High Oxygen concentrations result in increased production of oxygen free radicals and therefore lung tissue toxicity.
Affects lungs and CNS.
The higher PO2 or longer the exposure time, the greater the likelihood of lung damage.

Question 7

Explain how to reduce the risk of Retinopathy of Prematurity or Retrolental Fibroplasia (RLP)

Answer 7

Recommended–oxygen supplementation should not result in a PaO2 of more than 80mmHg in premature infants

Question 8

Name conditions that require use of high Oxygen concentrations.

Answer 8

Shock, Carbon monoxide poisoning, cyanide poisoning, smoke inhalation, severe trauma, Acute myocardial infarction

Question 9

Name the indications for an Arterial Blood Gas.

Answer 9

1. Need to evaluate adequacy of ventilatory (PaCO2 and pH) and oxygenation (PaO2 and SaO2) status, and oxygen-carrying capacity of blood
2. Need to quantitate the patient’s response to therapeutic intervention and/or diagnostic evaluation
3. Need to monitor severity and progression of a documented disease process

Question 10

Name the Contraindications for ABG

Answer 10

1. Negative results of a modified Allen test (collateral circulation test) are indicative of inadequate blood supply to the hand. Suggests the need to select another extremity for puncture
2. Arterial punctures should not be performed through a lesion or distal to surgical shunt or if there is evidence of infection/peripheral vascular disease involving selected limb, choose alternate site.
3. Femoral punctures should not be performed outside of hospital
4. Coagulopathy or medium-to-high dose anticoagulation therapy may be a relative contraindication for ABG

Question 11

Name hazards or complications for an ABG

Answer 11

1. Hematoma
2. Arteriospasm
3. Air or clotted-blood emboli
4. Anaphylaxis from local anesthestic
5. Introducing infection to patient
6. Hemorrhage
7. Trauma to vessel
8. Arterial occlusion
9. Vasovagal response
10. Pain

Question 12

Name limitations measuring the results for an ABG.

Answer 12

1. Artery may be inaccessible due to overlying tissues
2. Pulse may not be palpable
3. Arteriospasm may preclude collection despite successful introduction of needle into artery
4. Arterial blood specimens only reflect physiologic condition at moment of sampling
5. Specimens from mechanically ventilated patients with minimal pulmonary pathology adequately reflect effects of oxygen conc. change 10 minutes after change. At least 20-30 minutes in spontaneously breathing patients
6. Specimens held at room temp must be analyzed within 10-15 minutes of drawing; iced samples should be analyzed withing the hour

Question 13

Describe the purpose of an oxygen analyzer.

Answer 13

Used to measure the amount of oxygen being supplied by various oxygen delivery devices (mainly high-flow devices)

Question 14

Describe how the Galvanic electrochemical analyzers function.

Answer 14

Utilizes fuel cell
As a chemical rxn occurs while oxygen crosses a semi-permeable membrane and reacts with water and electrolyte solution, the flow of electrons is read as flow of current (which is proportional to partial pressure of oxygen)

Question 15

Describe the limitations of oxygen analyzers.

Answer 15

.Maintenance and malfunctioning (due to low batteries or analyzers needing replacement fuel cells or Clark electrodes)

Question 16

Describe how to calibrate an oxygen analyzer, and the importance of calibrating.

Answer 16

Zero screen, calibrate to room air, place in bag oxygen tubing and 100% O2 and have analyzer go to or within 3 of 100%. Calibrate devices using O2 over 50% to 100%

Question 17

Name the physiological effects of nitric oxide.

Answer 17

When inhaled, it improves blood flow to ventilated alveoli. Results in reduction in intrapulmonary shunting, improvement in arterial oxygenation, and decrease in pulmonary vascular resistance.

Question 18

Describe what will cause the FIO2 be altered when using an air entrainment mask.

Answer 18

When the flow output decreases below a patient’s inspiratory flow, it will cause air-dilution making the FiO2 to become variable

Question 19

Explain how Heliox is delivered to the patient.

Answer 19

Must always be mixed with Oxygen. Must be delivered in tightly closed system (nonrebreathing mask, ET tube or Tracheostomy tube)

Question 20

Define low-flow device.

Answer 20

Variable flow device that may provide less gas than the patient is breathing in.

Question 21

Define High-flow device.

Answer 21

Fixed flow devices consistently provide a gas flow that meets or exceeds the patient’s inspiratory flow rates

Question 22

List the indications for HBO therapy.

Answer 22

Air embolism and Acute Carbon Monoxide poisoning

Question 23

List the complications of HBO therapy.

Answer 23

1. Ear/Sinus trauma
2. Pneumothorax
3. Air embolism
4. Oxygen Toxicity
5. Fire
6. Sudden decompression
7. Claustrophobia

Question 24

List the criterion for HBO therapy.

Answer 24

1. History of unconsciousness
2. Presence of neuropsychiatric abnormality
3. Cardiac instability or cardiac ischemia
4. Carboxyhemoglobin level at 25% or higher

Question 25

Explain oxygen content available from oxygen tents.

Answer 25

Operates at 7-15 L/minute. Reservoir capacity is 2 L/min with 5 L/min output

Question 26

Explain half-life of carboxyhemoglobin when using HBO therapy versus oxygen via mask.

Answer 26

If patient breathes air–half life of 5 hours

Breathing 100% oxygen reduces half life to 80 minutes

Under HBO at 3 ATA half life is 23 minutes

Question 27

Explain oxyhood and flow rates.

Answer 27

.Minimum flow rate of 7 L/min to prevent CO2 build up. 10-15 L/min may be needed to maintain stable FiO2. 15 is the max due to noise.

Question 28

FiO2 greater than 0.5 may cause…

Answer 28

Complication of Oxygen Therapy–Atelectasis, Oxygen Toxicity, and/or ciliary or leukocyte depression

Question 29

Retinopathy of Prematurity

Answer 29

Complication of Oxygen Therapy–In premature infants, PaO2 greater than 80 mmHg may contribute to this.

Question 30

Minimal FiO2 should be used during laser bronchoscopy or tracheostomy to avoid

Answer 30

Complication of Oxygen Therapy–Intratracheal ignition

Question 31

High FiO2 increases presence of….

Answer 31

Complication of Oxygen Therapy–Fire Hazard

Question 32

When using Oxygen therapy, nebulizers and humidifiers can cause

Answer 32

Complication of Oxygen Therapy–Bacterial Contamination

Question 33

Oxygen flow directed at an infants face…

Answer 33

Complication of Oxygen Therapy–May stimulate an alteration in respiratory pattern

Question 34

Infants with congenital heart lesions, high PaO2 can compromise….

Answer 34

Complication of Oxygen Therapy–Balance between pulmonary and systemic flow

Question 35

Describe how a Polargraphic oxygen analyzer functions.

Answer 35

Utilizes Clark electrode. Platinum cathode and silver-silver chloride anode are immersed in potassium hydroxide bath, a (-volt battery is used to polarize anode to speed the electrochemical reaction