Evolve RTH 236 Chapter 8

What is a decrease in tissue oxygenation called?

Hypoxia

What could cause tissue hypoxia with normal arterial oxygenation?

Inadequate cardiac output

Hypoxemia levels

Mild 79-60 Moderate 59-40 Severe <40

Where is the most common site for arterial puncture?

Radial

A patient has the following ABG results:pH 7.25, PaCO2 32 mm Hg, HCO3- 16 mEq/L, base excess -10 mEq/LBased on these findings, the patient has which of the following?

Uncompensated metabolic acidosis

A 35-year-old, 54 kg woman with congestive heart failure enters the emergency department short of breath. An ABG shows the following results:pH 7.50, PaCO2 30 mm Hg, HCO3- 23 mEq/L, base excess +2 mEq/LThe patient's ABG results indicate what?

Uncompenssted respiratory alkalosis

What is the most common physiologic cause of hypoxemia in patients with lung disease?

V/Q mismatching is the most common physiologic cause of hypoxemia in patients with lung disease.

For the test of collateral circulation in an Allen's test, "pinking up" of the hand is normal if it occurs within ____ s.?

3-5

What is the normal value for PaO2 in the adult patient breathing room air?

80-100 mmHg

What is often the first clinical sign that suggests the presence of hypoxemia?

Exertional dyspnea

An acute increase in PaCO2 of 10 to 15 mm Hg causes a corresponding increase in plasma HCO3- of how many mEq/L?

1 For acute respiratory acidosis, the plasma HCO3- increases by 1 mEq/L for each 10 to 15 mm Hg that the PaCO2 increases.

What is the normal CaO2?

16 to 20 mL/dL

A 17-year-old man is brought into the emergency department. Vitals are as follows: pulse, 100 beats/min; respiratory rate, 4 breaths/min; and blood pressure, 100/65 mm Hg. The patient was at a party, where he was discovered by his friends to be slumped in a chair and unresponsive. ABG results are as follows:pH 7.29, PaCO2 68 mm Hg, HCO3- 29 mEq/L, BE + 1 mEq/LThe patient's acid-base status is classified as which of the following? A) Uncompensated respiratory acidosis B) Uncompensated metabolic acidosis C) Partially compensated respiratory acidosis D) Compensated respiratory alkalosis

A

Which of the following is true regarding respiratory alkalosis? A) The PaCO2 is less than 35 mm Hg. Respiratory alkalosis, which is identified by a PaCO2 below the expected level (35 to 45 mm Hg), indicates that ventilation is exceeding the normal level. Hyperventilation usually is the result of an increased stimulus or drive to breathe. This occurs with pain, hypoxemia (PaO2 <60 mm Hg), acidosis, and anxiety. B) It is called completely compensated if the pH is 7.52. Respiratory alkalosis, which is identified by a PaCO2 below the expected level (35 to 45 mm Hg), indicates that ventilation is exceeding the normal level. Hyperventilation usually is the result of an increased stimulus or drive to breathe. This occurs with pain, hypoxemia (PaO2 <60 mm Hg), acidosis, and anxiety.

A

A patient is transported to the emergency department after being found unconscious in a vehicle with the engine running and the garage door closed. You apply 15 L/min of oxygen via nonrebreathing mask and obtain the following vital signs: HR: 150, RR: 34, SpO2 100%. What would you recommend ?

ABG analysis with CO-oximetry

What is the primary method of transporting oxygen in the blood?

Bound to oxygen

Which of the following could cause metabolic acidosis? A) Hypokalemia B) Vomiting C) Renal Disease D) Cardiovascular disease

C

Which of the following is a true statement regarding the term hypoxemia? A) It is always considered a severe disorder. When the measured PaO2 is below the predicted range for a patient breathing room air, regardless of the actual FIO2, this is called hypoxemia. B) It is independent of the age of the patient. When the measured PaO2 is below the predicted range for a patient breathing room air, regardless of the actual FIO2, this is called hypoxemia. C) It occurs when the patient's PaO2 is lower than predicted. When the measured PaO2 is below the predicted range for a patient breathing room air, regardless of the actual FIO2, this is called hypoxemia.

C

Which of the following shifts the oxyhemoglobin dissociation curve to the left? A) Increased body temperature B) Increased PaCO2 C) Fetal hemoglobin D) Decreased pH

C

Which of the following would be best used to assess arterial oxygenation?

CaO2

What is the direct effect of an increased PaCO2 on HCO3-?

Causes it to increase

Given the following ABG results, interpret the acid-base status:pH 7.44, PaCO2 25 mm Hg, HCO3- 17 mEq/L, base excess -6 mEq/L

Compensated respiratory alkalosis

The negative log of the hydrogen ion concentration is defined as which of the following? A) Standard HCO3 B) PaCO2 C) Base excess D) pH

D

Which of the following is a correct representation of the Henderson-Hasselbalch equation? A) pK = pH - log (PaCO2 · 0.03)/HCO3- B) -pH = pK - log HCO3-/(PaCO2 · 0.03) C) pK = pH - log HCO3-/(PaCO2 · 0.03) D) pH = pK + log HCO3-/(PaCO2 · 0.03)

D

Which of the following is the best indicator of metabolic acid-base status? A) Standard HCO3 B) Plasma HCO3 C) T40 HCO3 D) Base excess

D

Which of the following ratios of HCO3-/PaCO2 results in a pH of 7.40? A) 24:1 B) 6:0.3 C) 15:1 D) 20:1

D

A shift to the right in the oxyhemoglobin dissociation curve has what effect on the affinity of hemoglobin for oxygen?

Decreased

A 32-year-old man comes to the emergency department after a traffic accident with the following data: pulse, 118 beats/min; respiratory rate, 27 breaths/min; blood pressure, 100/68 mm Hg; paradoxical chest movement on the left side; breath sounds decreased on the left; and ABG on room air (21%) as follows: pH, 7.32; PaCO2, 70 mm Hg; PaO2, 57 mm Hg; HCO3-, 23 mEq/L; base excess, 0; SaO2, 86%, CaO2, 15.2 vol%; Hb, 13.0 g/dL; P(A-a)O2, 18 mm Hg. Based on this information, what is the primary cause of the patient's hypoxemia?

Overall Hypoventilation

What would be the best indicator of tissue oxygenation?

PO2

What parameter is the respiratory component of acid-base balance ?

PaCO2

What parameters is the respiratory component of acid-base status?

PaCO2

You are taking care of a patient receiving invasive mechanical ventilation. You are reading the chart and notice the PaCO2 decreased from 52 to 40 mmHg. What parameter would likely increase?

pH