Arterial Blood Gas Interpretation Practice Quiz (Part 1: 20 Items)21/2022 update

Arterial Blood Gas Interpretation Practice Quiz (Part 1: 20 Items) 1. 1. Question George Kent is a 54-year-old widower with a history of chronic obstructive pulmonary disease and was rushed to the emergency department with increasing shortness of breath, pyrexia, and a productive cough with yellow-green sputum. He has difficulty communicating because of his inability to complete a sentence. One of his sons, Jacob, says he has been unwell for three days. Upon examination, crackles and wheezes can be heard in the lower lobes; he has tachycardia and a bounding pulse. Measurement of arterial blood gas shows pH 7.3, PaCO2 68 mm Hg, HCO3 28 mmol/L, and PaO2 60 mm Hg. How would you interpret this? o A. Respiratory Acidosis, Uncompensated o B. Respiratory Acidosis, Partially Compensated o C. Metabolic Alkalosis, Uncompensated o D. Metabolic Acidosis, Partially Compensated Incorrect Correct Answer: B. Respiratory Acidosis, Partially Compensated The patient has respiratory acidosis (raised carbon dioxide) resulting from an acute exacerbation of chronic obstructive pulmonary disease, with partial compensation. 2. 2. Question Carl, an elementary student, was rushed to the hospital due to vomiting and a decreased level of consciousness. The patient displays slow and deep (Kussmaul breathing), and he is lethargic and irritable in response to stimulation. He appears to be dehydrated—his eyes are sunken and mucous membranes are dry—and he has a two-week history of polydipsia, polyuria, and weight loss. Measurement of arterial blood gas shows pH 7.0, PaO2 90 mm Hg, PaCO2 23 mm Hg, and HCO3 12 mmol/L; other results are Na+ 126 mmol/L, K+ 5 mmol/L, and Cl- 95 mmol/L. What is your assessment? o A. Respiratory Acidosis, Uncompensated o B. Respiratory Acidosis, Partially Compensated o C. Metabolic Alkalosis, Uncompensated o D. Metabolic Acidosis, Partially, Compensated Incorrect Correct Answer: D. Metabolic Acidosis, Partially, Compensated The student was diagnosed with diabetes mellitus. The results show that he has metabolic acidosis (low HCO3 -) with respiratory compensation (low CO2). 3. 3. Question A cigarette vendor was brought to the emergency department of a hospital after she fell into the ground and hurt her left leg. She is noted to be tachycardic and tachypneic. Painkillers were carried out to lessen her pain. Suddenly, she started complaining that she is still in pain and now experiencing muscle cramps, tingling, and paraesthesia. Measurement of arterial blood gas reveals pH 7.6, PaO2 120 mm Hg, PaCO2 31 mm Hg, and HCO3 25 mmol/L. What does this mean? o A. Respiratory Alkalosis, Uncompensated o B. Respiratory Acidosis, Partially Compensated o C. Metabolic Alkalosis, Uncompensated o D. Metabolic Alkalosis, Partially Compensated Incorrect Correct Answer: A. Respiratory Alkalosis, Uncompensated The primary disorder is acute respiratory alkalosis (low CO2) due to the pain and anxiety causing her to hyperventilate. There has not been time for metabolic compensation. 4. 4. Question Ricky’s grandmother has been suffering from persistent vomiting for two days now. She appears to be lethargic and weak and has myalgia. She is noted to have dry mucus membranes and her capillary refill takes >4 seconds. She is diagnosed as having gastroenteritis and dehydration. Measurement of arterial blood gas shows pH 7.5, PaO2 85 mm Hg, PaCO2 40 mm Hg, and HCO3 34 mmol/L. What acid-base disorder is shown? o A. Respiratory Alkalosis, Uncompensated o B. Respiratory Acidosis, Partially Compensated o C. Metabolic Alkalosis, Uncompensated o D. Metabolic Alkalosis, Partially Compensated Incorrect Correct Answer: C. Metabolic Alkalosis, Uncompensated The primary disorder is uncompensated metabolic alkalosis (high HCO3 -). As CO2 is the strongest driver of respiration, it generally will not allow hypoventilation as compensation for metabolic alkalosis. 5. 5. Question Mrs. Johansson, who had undergone surgery in the post-anesthesia care unit (PACU), is difficult to arouse two hours following surgery. Nurse Florence in the PACU has been administering Morphine Sulfate intravenously to the client for complaints of post-surgical pain. The client’s respiratory rate is 7 per minute and demonstrates shallow breathing. The patient does not respond to any stimuli. The nurse assesses the ABCs (remember Airway, Breathing, Circulation!) and obtains ABGs STAT! Measurement of arterial blood gas shows pH 7.10, PaCO2 70 mm Hg, and HCO3 24 mEq/L. What does this mean? o A. Respiratory Alkalosis, Partially Compensated o B. Respiratory Acidosis, Uncompensated o C. Metabolic Alkalosis, Partially Compensated o D. Metabolic Acidosis, Uncompensated Incorrect Correct Answer: B. Respiratory Acidosis, Uncompensated The results show that Mrs. Johansson has respiratory acidosis because of decreased pH and increased PaCO2 which means acidic in nature. Meanwhile, it is uncompensated because HCO3 is within the normal range. 6. 6. Question Baby Angela was rushed to the Emergency Room following her mother’s complaint that the infant has been irritable, difficult to breastfeed, and has had diarrhea for the past 3 days. The infant’s respiratory rate is elevated and the fontanels are sunken. The Emergency Room physician orders ABGs after assessing the ABCs. The results from the ABG results show pH 7.39, PaCO2 27 mmHg, and HCO3 19 mEq/L. What does this mean? o A. Respiratory Alkalosis, Fully Compensated o B. Metabolic Acidosis, Uncompensated o C. Metabolic Acidosis, Fully Compensated o D. Respiratory Acidosis, Uncompensated Incorrect Correct Answer: C. Metabolic Acidosis, Fully Compensated Baby Angela has metabolic acidosis due to decreased HCO3 and slightly acidic pH. Her pH value is within the normal range which made the result fully compensated. 7. 7. Question Mr. Wales, who underwent post-abdominal surgery, has a nasogastric tube. The nurse on duty notes that the nasogastric tube (NGT) is draining a large amount (900 cc in 2 hours) of coffee ground secretions. The client is not oriented to person, place, or time. The nurse contacts the attending physician and STAT ABGs are ordered. The results from the ABGs show pH 7.57, PaCO2 37 mmHg and HCO3 30 mEq/L. What is your assessment? o A. Metabolic Acidosis, Uncompensated o B. Metabolic Alkalosis, Uncompensated o C. Respiratory Alkalosis, Uncompensated o D. Metabolic Alkalosis, Partially Compensated Incorrect Correct Answer: B. Metabolic Alkalosis, Uncompensated The postoperative client’s ABG results show that he has metabolic alkalosis because of an increased pH and HCO3. It is uncompensated due to the normal PaCO2 which is within 35 to 45 mmHg. 8. 8. Question Client Z is admitted to the hospital and is to undergo brain surgery. The client is very anxious and scared of the upcoming surgery. He begins to hyperventilate and becomes very dizzy. The client loses consciousness and the STAT ABGs reveal pH 7.61, PaCO2 22 mmHg, and HCO3 25 mEq/L. What is the ABG interpretation based on the findings? o A. Metabolic Acidosis, Uncompensated o B. Respiratory Alkalosis, Partially Compensated o C. Respiratory Alkalosis, Uncompensated o D. Metabolic Alkalosis, Partially Compensated Incorrect Correct Answer: C. Respiratory Alkalosis, Uncompensated The results show that client Z has respiratory alkalosis since there is an increase in the pH value and a decrease in PaCO2 which are both basic. It is uncompensated due to the normal HCO3 which is within 22-26 mEq/L. 9. 9. Question Three-year-old Adrian is admitted to the hospital with a diagnosis of asthma and respiratory distress syndrome. The mother of the child reports to the nurse on duty that she has witnessed slight tremors and behavioral changes in her child over the past four days. The attending physician orders routine ABGs following an assessment of the ABCs. The ABG results are pH 7.35, PaCO2 72 mmHg, and HCO3 38 mEq/L. What acid-base disorder is shown? o A. Respiratory Acidosis, Uncompensated o B. Respiratory Acidosis, Fully Compensated o C. Respiratory Alkalosis, Fully Compensated o D. Metabolic Alkalosis, Partially Compensated Incorrect Correct Answer: B. Respiratory Acidosis, Fully Compensated The patient has respiratory acidosis (raised carbon dioxide) resulting from asthma and respiratory distress syndrome, with compensation having normal pH value within 7.35to 7.45, increased PaCO2 which is acidic and increased HCO3 which is basic. 10. 10. Question Anne, who is drinking beer at a party, falls and hits her head on the ground. Her friend Liza dials “911” because Anne is unconscious, depressed ventilation (shallow and slow respirations), rapid heart rate, and is profusely bleeding from both ears. Which primary acid-base imbalance is Anne at risk for if medical attention is not provided? o A. Metabolic Acidosis o B. Metabolic Alkalosis o C. Respiratory Acidosis o D. Respiratory Alkalosis Incorrect Correct Answer: C. Respiratory Acidosis One of the risk factors of having respiratory acidosis is hypoventilation which may be due to brain trauma, coma, and hypothyroidism or myxedema. Other risk factors include COPD, Respiratory conditions such as pneumothorax, pneumonia, and status asthmaticus. Drugs such as Morphine and MgSO4 toxicity are also risk factors of respiratory acidosis. 11. 11. Question Dave, a 6-year-old boy, was rushed to the hospital following her mother’s complaint that her son has been vomiting, nauseated and has overall weakness. After a series of tests, the nurse notes the laboratory results: potassium: 2.9 mEq. Which primary acid-base imbalance is this boy at risk for if medical intervention is not carried out? o A. Respiratory Acidosis o B. Respiratory Alkalosis o C. Metabolic Acidosis o D. Metabolic Alkalosis Incorrect Correct Answer: D. Metabolic Alkalosis Vomiting, hypokalemia, overdosage of NaHCO3 and NGT suctioning are considered risk factors of metabolic alkalosis. 12. 12. Question An old beggar was admitted to the emergency department due to shortness of breath, fever, and a productive cough. Upon examination, crackles and wheezes are noted in the lower lobes; he appears to be tachycardic and has a bounding pulse. Measurement of arterial blood gas shows pH 7.2, PaCO2 66 mm Hg, HCO3 27 mmol/L, and PaO2 65 mm Hg. As a knowledgeable nurse, you know that the normal value for pH is: o A. 7.20 o B. 7.30 o C. 7.40 o D. 7.50 Incorrect Correct Answer: C. 7.40 Normal blood pH must be maintained within a narrow range of 7.35-7.45 to ensure the proper functioning of metabolic processes and the delivery of the right amount of oxygen to tissues. Acidosis refers to an excess of acid in the blood that causes the pH to fall below 7.35, and alkalosis refers to an excess of base in the blood that causes the pH to rise above 7.45. 13. 13. Question Liza’s mother is seen in the emergency department at a community hospital. She admits that her mother is taking many tablets of aspirin (salicylates) over the last 24-hour period because of a severe headache. Also, the mother complains of an inability to urinate. The nurse on duty took her vital signs and noted the following: Temp = 97.8 °F; apical pulse = 95; respiration = 32 and deep. Which primary acid-base imbalance is the client at risk for if medical attention is not provided? o A. Respiratory Acidosis o B. Respiratory Alkalosis o C. Metabolic Acidosis o D. Metabolic Alkalosis Incorrect Correct Answer. C. Metabolic Acidosis Salicylate overdose causes a high anion gap metabolic acidosis in both children and adults. Adults commonly develop a mixed acid-base disorder as a respiratory alkalosis due to direct respiratory center stimulation occurs as well. This second disorder is uncommon in children. 14. 14. Question A patient who is hospitalized due to vomiting and a decreased level of consciousness displays slow and deep (Kussmaul breathing), and he is lethargic and irritable in response to stimulation. The doctor diagnosed him of having dehydration. Measurement of arterial blood gas shows pH 7.0, PaO2 90 mm Hg, PaCO2 22 mm Hg, and HCO3 14 mmol/L; other results are Na+ 120 mmol/L, K+ 2.5 mmol/L, and Cl- 95 mmol/L. As a knowledgeable nurse, you know that the normal value for PaCO2 is: o A. 22 mm Hg o B. 36 mm Hg o C. 48 mm Hg o D. 50 mm Hg Incorrect Correct Answer: B. 36 mm Hg The normal range for PaCO2 is from 35 to 45 mm Hg. 15. 15. Question A company driver is found at the scene of an automobile accident in a state of emotional distress. He tells the paramedics that he feels dizzy, tingling in his fingertips, and does not remember what happened to his car. Respiratory rate is rapid at 34/minute. Which primary acid-base disturbance is the young man at risk for if medical attention is not provided? o A. Respiratory Acidosis o B. Respiratory Alkalosis o C. Metabolic Acidosis o D. Metabolic Alkalosis Incorrect Correct Answer: B. Respiratory Alkalosis Hyperventilation is typically the underlying cause of respiratory alkalosis. Hyperventilation is also known as overbreathing. When someone is hyperventilating, they tend to breathe very deeply or very rapidly. 16. 16. Question An elderly client was admitted to hospital in a coma. Analysis of the arterial blood gave the following values: PCO2 16 mm Hg, HCO3- 5 mmol/L and pH 7.1. As a well-rounded nurse, you know that the normal value for HCO3 is: o A. 20 mmol/L o B. 24 mmol/L o C. 29 mmol/L o D. 31 mmol/L Incorrect Correct Answer: B. 24 mmol/L The normal value for bicarbonate (HCO3) is 22-26 mmol/L or mEq/L. It may vary slightly among different laboratories. The given values show the common measurement range of results for these tests. Some laboratories use different measurements or may test different specimens. 17. 17. Question In a patient undergoing surgery, it was vital to aspirate the contents of the upper gastrointestinal tract. After the operation, the following values were acquired from an arterial blood sample: pH 7.55, PCO2 52 mm Hg and HCO3- 40 mmol/l. What is the underlying disorder? o A. Respiratory Acidosis o B. Respiratory Alkalosis o C. Metabolic Acidosis o D. Metabolic Alkalosis Incorrect Correct Answer: D. Metabolic Alkalosis NGT suctioning, vomiting, hypokalemia and overdosage of NaHCO3 are considered risk factors of metabolic alkalosis. 18. 18. Question A mountaineer attempts an assault on a high mountain in the Andes and reaches an altitude of 5000 meters (16,400 ft) above sea level. What will happen to his arterial PCO2 and pH? o A. Both will be lower than normal. o B. The pH will rise and PCO2 will fall. o C. Both will be higher than normal due to physical exertion. o D. The pH will fall and PCO2 will rise Incorrect Correct Answer: B. The pH will rise and PCO2 will fall. The mountaineer will suffer from a respiratory alkalosis. The decline in the PO2 with altitude will stimulate breathing to offset the hypoxia. Carbon dioxide is driven from the blood faster than it is produced in the tissues so PCO2 falls and pH rises. 19. 19. Question A young woman is found comatose, having taken an unknown number of sleeping pills an unknown time before. An arterial blood sample yields the following values: pH 6.90, HCO3- 13 meq/liter, and PaCO2 68 mmHg. This patient’s acid-base status is most accurately described as: o A. Metabolic Acidosis o B. Respiratory Acidosis o C. Simultaneous Respiratory and Metabolic Acidosis o D. Respiratory Acidosis with Complete Renal Compensation Incorrect Correct Answer: C. Simultaneous Respiratory and Metabolic Acidosis Whenever the PCO2 and HCO3 are abnormal in opposite directions, ie, one above normal while the other is reduced, a mixed respiratory and metabolic acid-base disorder exists. When the PCO2 is elevated and the [HCO3-] reduced, respiratory acidosis and metabolic acidosis coexist. 20. 20. Question A mother is admitted to the emergency department following complaints of fever and chills. The nurse on duty took her vital signs and noted the following: Temp = 100 °F; apical pulse = 95; respiration = 20 and deep. Measurement of arterial blood gas shows pH 7.37, PaO2 90 mm Hg, PaCO2 40 mm Hg, and HCO3 24 mmol/L. What is your assessment? o A. Hyperthermia o B. Hyperthermia and Respiratory Alkalosis o C. Hypothermia o D. Hypothermia and Respiratory Alkalosis Incorrect Correct Answer: A. Hyperthermia An individual is considered to have hyperthermia if he or she has a temperature of >37.5 or 38.3 °C (99.5 or 100.9 °F). The measurement of arterial blood gases are normal.