Diagnostic Testing - Workbook Questions Flashcards
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
What is the childs PAO2?
150
210
300
350
300
FiO2 x 7) - (PaCO2 + 10
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
What is the child’s A-aDO2? (A-a Gradient?)
240
290
340
410
240
(FiO2 x 7) - (PaCO2 + 10) = 300
300-60 = 240
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
What is the child’s a/A Ratio?
- 1
- 2
- 3
- 4
0.2
60 divided by 300 = 0.2
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
What is the Qs/Qt if the C (a-v)O2 is 3.3 vol%?
- 2%
- 9%
- 6%
- 5%
17.5%
Remember, you don’t have to use the shunt equation! Normal shunt is 5%, add 5% for every 100 of A-a gradient. This child has an A-a gradient of 240, meaning that the shunt is already above 15%, leaving only one logical choice.
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
How would you interpret this ABG?
Short answer: Metabolic alkalosis
Long answer: Uncompensated (acute) metabolic alkalosis w/ mild hypoxemia.
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
The patients hypoxemia is most likely the result of
alveolar hypo-ventilation
ventilatory failure
pulmonary shunting
ventilation-perfusion (VQ) mismatch
ventilation-perfusion (VQ) mismatch.
Remember… Hypoxemia has 3 causes;
poor ventilation (CO2 elevated? NO)
vq mismatch (CO2 normal, FiO2 under 60? YES)
shunt. (FiO2 over 60, refractory hypoxemia? NO)
The Fio2 is <60%, and the PaCO2 is normal. This is a VQ mismatch.
A 4 year old child is receiving 50% oxygen via simple mask. The following ABG results are available:
pH: 7.51 PaCO2: 40 PaO2: 60 HCO3: 33 BE: +9
The initial therapy for this child should be to
increase FiO2
initiate mechanical ventilation
initiate CPAP
administer KCl
Increase FiO2. (up to 60%)
*Rationale for this solution is shown on page B-36 in the study guide
Which of the following is not a cause of increased shunting?
Pulmonary emboli
Atelectasis
Pulmonary edema
Pneumonia
pulmonary emboli
*Note this question has no rationale in the text or audio.
The forced vital capacity of an 8 year old is significantly below the predicted normal value. There is no change following administration of albuterol via MDI. This would be most consistent with which of the following disorders?
asthma
bronchitis
cystic fibrosis
skeletal deformity
skeletal deformity.
Remember… the first 3 choices (asthma, bronchitis, and CF) are all OBSTRUCTIVE pathologies. FVC is a measurement of VOLUME and indicates RESTRICTIVE pathologies. There is only 1 restrictive pathology in the choices given.
Which of the following is the least appropriate assessment of an infant’s oxygenation status?
arterialized capillary sample
umbilical artery line
pulse oximeter
transcutaneous electrode
arterialized capillary sample.
a capillary sample will never give an accurate PaO2 reading.
An infant is considered to be at high risk for SIDS. Which of the following items should be used to monitor the infant?
Apnea monitor
Capnograph
Oximeter
Transcutaneous monitor
Apnea monitor.
A 16 year old child with ARDS is being treated with mechanical ventilation and PEEP. The patient has persistent hypoxemia. This would result in an increase in which of the following hemodynamic measurements?
PAP
CVP
PCWP
Qt (Cardiac output)
PAP.
Remember, if the problem is in the lungs, think PAP. ARDS is a disease of the lungs.
The neonatal-pediatric specialist is unable to obtain a pulmonary capillary wedge pressure. Which of the following could be substituted for the wedge pressure?
pulmonary artery diastolic pressure
pulmonary artery systolic pressure
pulmonary vascular resistance
central venous pressure
pulmonary artery diastolic pressure.
*noted on page B-48 #4 in the study guide
The FEV1 measured for a 12 year old child is significantly below the predicted normal value. There is marked improvement following the administration of albuterol via HHN. These results would be consistent with which of the following disorders?
asthma
kyphosis
pneumonia
atelectasis
Asthma.
Disregard reversibility for a second and lets remember the rules of the exam. FEV1 is a measurement of FLOW, and indicates OBSTRUCTIVE pathologies. Asthma is the only obstructive pathology of the 4 choices.
Your 4 OBSTRUCTIVE pathologies: CF, bronchitis, asthma, and bronchiectasis.
A neonatal-pediatric specialist has inserted a balloon-tip, flow-directed pulmonary artery catheter and has recorded the following measurements:
CVP 2
PAP 8
PCWP 3
Qt 2.5
Which of the following is the most likely cause of these results?
High PEEP effects
Hemorrhage
Overhydration
Pulmonary hypertension
Hemorrhage.
All of the values are low, which indicates hypovolemia. Hemorrhage is the only choice which would cause hypovolemia.
