A patient receiving O2 via concentrator at 2Lmin at home complains he cant feel O2

TMC PRACTICE

A patient receiving O2 via concentrator at 2L/min at home complains he can't feel O2 coming out the prongs of the cannula. Which of the following should the RT do first?

• Place the cannula under water and see if bubbling occurs
• Attach the cannula to a cylinder/flowmeter setup
• Increase the flow to 5L/min
• Replace the concentrator with a new one - >>>>a. Place the cannula under water

and see if bubbling occurs

The first step is to check to make sure there is flow passing through the cannula by having the patient remove the cannula and place it in a cup of water. Bubbling will occur if there is flow. If no bubbling occurs, the patient should make sure the cannula is attached to the flowmeter outlet and the flowmeter is turned on. If there's any doubt, the patient should connect the cannula to the cylinder back-up and call the home care company.

A pt is breathing 16 times per minute and has a Vt of 450mL. What is this pt's minute ventilation?

• 4.2L
• 6.1L
• 7.2L
• 8.6L - >>>>c. 7.2L

Vt x R = Ve

A pt is breathing spontaneously using a 50% aerosol mask with the following ABG:

ph: 7.36

CO2: 43

O2: 48

HCO3: 24

Based on this information, the most appropriate recommendation is which of the following?

• Initiate CPAP
• Increase the O2 percentage to 70%
• Change to a nonrebreathing mask
• Change to a simple O2 mask at 10L/min - >>>>a. Initiate CPAP

A PaO2 of 55 mm Hg on 50% oxygen indicates refractory hypoxemia. Increasing the FIO2 most likely won't improve the PaO2 in addition to increasing the potential for lung

damage. Applying CPAP to help recruit alveoli and allow for more surface area for oxygen to be able to enter the blood is more appropriate

A pt is receiving mechanical ventilation with the following settings

Vt: 750

RR: 12

Mode: AC

PEEP: 10

FiO2: 80%

pH: 7.41

CO2: 38

O2: 174

Based on these information, what would be the appropriate ventilator settings?

• Decrease PEEP to 8
• Decrease FiO2 to 70%
• Decrease Vt to 650
• Increase Insp. Flow - >>>>b. Decrease FiO2 to 70%

Because the patient is hyperoxygenating, the PaO2 may be decreased by reducing FIO2 or PEEP. Because the FIO2 is 0.80, it should be reduced first. Once the FIO2 is 0.50-0.60, the PEEP should then be decreased.

The reduction in urinary output caused by mechanical ventilation may be the result of

• Decreased renal blood flow
• Decreased production of ADH
• Increased renal blood flow
• Increased production ofADH

• 1 only
• 1 and 4
• 2 and 3
• 3 and 4 - >>>>b. 1 and 4

Positive pressure ventilation has the potential for decreasing venous blood return to the heart. This results from this pressure being transferred to the superior and inferior vena cavae, which restricts blood flow back into the heart. Baroreceptors (pressure receptors) sense this lower pressure in the right atrium and send signals to the brain, which causes an increased production of ADH by the pituitary gland. This causes the body to hold on to more fluid as a compensatory mechanism because the right side of the heart is sensing a low pressure. The decreased cardiac output results in decreased perfusion to the kidneys, which also reduces urine output.

Which values indicate that a patient is most likely ready to be weaned from mechanical ventilation?

• Vd/Vt Ratio of .45
• MIP of -31cmH2O
• RSBI of 145
• VC of 8

• 1 and 2
• 2 and 3
• 1, 2 and 4
• 2, 3 and 4 - >>>>a. 1 and 2

A VD/VT of less than 0.60 and an MIP of at least -20 cm H2O indicate weaning should be attempted. For weaning to be attempted, RSBI needs to be less than 105 and the VC more than 10 to 15 mL/kg of body weight.

A pt receiving VC ventilation with a Vt of 800mL, the exhaled volume displayed is reading 500mL. The RT wants to determine the volume that the ventilator is actually delivering. To most accurately measure this volume, the RT should place a respirometer at the

• Exhalation valve
• Patient wye connector
• Ventilator outlet
• Humidifier outlet - >>>>c. Ventilator outlet

The respirometer should be placed at the ventilator outlet because if it is placed anywhere else in the circuit and a leak is present, the reading will not be accurate.

A pt is receiving VC ventilation in AC Mode. The low pressure alarm is sounding. Which of the following may be the cause of the alarm activation?

• Water in the tubing
• Pt disconnected from the ventilator
• Secretions in the pt's airway
• Kink in the ventilator tubing - >>>>b. Pt disconnected from the ventilator

The low-pressure alarm on volume-controlled ventilation will be activated if the patient becomes disconnected from the circuit or if leaks are present in the system. Choices A, C, and D could result in the high-pressure alarm being activated as a result of increased airway resistance.

You have just obtained blood from the pt's radial artery to determine ABG results. As you run the blood through the blood gas analyzer, you notice you failed to remove an air bubble from the sample. The blood gas results will most likely reflect values with a

• High pH and Low PO2
• Low PCO2 and Low PO2
• Low PCO2 and High PO2
• High PCO2 and High PO2 - >>>>c. Low PCO2 and High PO2

Because air contains little CO2 and a much higher amount of O2, these values will be reflected if an air bubble is in the sample.

You are monitoring a GBS for signs of respiratory muscle weakness. Which one of the following variables would signal the earliest indication?

• PaO2
• PaCO2
• MIP
• Vt - >>>>c. MIP

MIP, sometimes referred to as NIF, measures the patient's respiratory muscle strength.It is obtained when the patient inhales as deeply as possible through a mouthpiece or mask that is attached to a pressure manometer. The MIP is measured periodically in patients with neuromuscular disease to determine weakness in the ventilatory muscles.A normal MIP is -50 to -100 cm H2O.

After PEEP is initiated for a patient, the RT should expect which of the following to occur?

• Increased FRC
• Increased Pplat
• Increased Lung Compliance
• Decreased P(A-a)O2

• 1 and 2
• 3 and 4
• 1, 3 and 4
• 2, 3 and 4 - >>>>c. 1, 3 and 4

PEEP increases FRC by recruiting collapsed alveoli. This results in a decrease in the plateau pressure (pressure needed to ventilate the lungs) and an increase in lung compliance. When more alveoli are opened, more oxygen will diffuse into the blood, which will increase the PaO2 and result in a decrease in the A-a gradient

A 70kg (154lb) patient in the ICU is receiving VC ventilation in he AC Mode, Rate of 10,

Vt of 700, PEEP of 5 on a 40% FiO2. ABG levels are as followed:

pH: 7.52

CO2: 31

O2: 57

HCO3: 23