Homework 6 Ch13 Acid-Base Assessment Ch14 Oxygenation and Lung Protective PDF

2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective Due Feb 20 at 1pm Points 125 Questions 119 Time Limit None A...

2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective Due Feb 20 at 1pm Points 125 Questions 119 Time Limit None Allowed Attempts 2 Take the Quiz Again Attempt History LATEST Attempt Time Score Attempt 1 125 minutes 117.93 out of 125 Score for this attempt: 117.93 out of 125 Submitted Feb 13 at 12:58pm This attempt took 125 minutes. Question 1 1 / 1 pts Which of the following will likely be seen in the arterial blood gas values of a patient with acute ventilatory failure? 1. Acidic pH 2. Near-normal bicarbonate level 3. Alkaline pH 4. High carbon dioxide level Correct! 1, 2, 4 2, 3, 4 2, 3 1, 4 An alkaline pH could be caused by hyperventilation. Ventilatory failure with a high CO2 level would cause an acidotic pH, with a near-normal bicarbonate level. Question 2 1 / 1 pts Which of the following would be considered a normal arterial carbon dioxide pressure (PaCO2) in a healthy individual? 45 to 60 mm Hg Correct! 35 to 45 mm Hg 60 to 80 mm Hg 25 to 35 mm Hg https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 1/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 The normal PaCO2 range is 35 to 45 mm Hg; below this is hypocapnia, and above this is hypercapnia. Question 3 1 / 1 pts An anion gap of 17 would indicate: respiratory acidosis. Correct! metabolic acidosis. metabolic alkalosis. respiratory alkalosis. An anion gap of 16 or higher would indicate a metabolic acidosis. The normal gap is 9 to 14 mEq/L. Question 4 0 / 1 pts Common causes of metabolic acidosis include: 1. diabetic ketoacidosis. 2. prolonged diarrhea 3. lactic acidosis. 4. renal failure. 1 1, 3, 4 2, 3 You Answered 2, 3, 4 Correct Answer 1, 2, 3, 4 Common causes of metabolic acidosis: diabetic ketoacidosis, pancreatic fistula; prolonged diarrhea), renal failure, renal tubular loss: failure to reabsorb HCO3renal tubular acidosis, Ingestion of acids Salicylate intoxication, Lactic acidosis. Question 5 1 / 1 pts Common causes of metabolic alkalosis include: 1. renal failure. 2. prolonged vomiting. 3. nasogastric drainagen. 4. Hypokalemia. https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 2/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 1, 3 1, 2, 3 Correct! 2, 3, 4 2, 4 Renal failure does not cause metabolic alkalosis.Common causes of metabolic alkalosis :Loss of fixed acids (prolonged vomiting; nasogastric drainage), gain of blood buffer base Hypokalemia and hypochloremia Question 6 1 / 1 pts Which of the following ABG results would strongly indicate the need for mechanical ventilation? pH 7.52; PaCO2 51; HCO3 40; PaO2 46 pH 7.56; PaCO2 27; HCO3 23; PaO2 63 Correct! pH 7.21; PaCO2 68; HCO3 26; PaO2 51 pH 7.36; PaCO2 79; HCO3 43; PaO2 63 Acute ventilatory failure is not associated with a typical ventilatory pattern. For example, the patient may demonstrate apnea, severe hyperpnea, or tachypnea. The bottom line is that acute ventilatory failure can develop in response to any ventilatory pattern that does not provide adequate alveolar ventilation. When an increased PaCO2 is accompanied by acidemia (decreased pH), acute ventilatory failure, or respiratory acidosis, is said to exist. Clinically, this is a medical emergency that may require mechanical ventilation. Question 7 1 / 1 pts A respiratory therapist is questioning the accuracy of the ABG results obtained on a patient in the ICU. The results show a pH and PaO2 that seem unreasonably high, while the PaCO2 seems unreasonably low. Which of the following would most likely cause these erroneous results? A venous sample was obtained. There was excessive heparin in the blood gas syringe. The sample was excessively delayed in analysis. Correct! There was an air bubble in the sample. An air bubble in the sample would cause an increase in the pH and PaO2 while causing a decrease in PaCO2. https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 3/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Question 8 1 / 1 pts Calculate the anion gap using the following data: Na+: 140 mEq/L K+ 4.1 mEq/L Cl-: 105 mEq/L HCO3-: 24 mEq/L 21 mEq/L. Correct! 11 mEq/L. 31 mEq/L. More information is needed to calculate. The anion gap is the calculated difference between the Na+ ions and the sum of the HCO3- and Clions. The potassium is not needed in this calculation. Question 9 1 / 1 pts The primary goal of acid-base homeostasis is to maintain which of the following? Normal HCO3– Correct! Normal pH Normal PCO2 Normal PO2 Acid-base balance refers to physiological mechanisms that keep the H+ ion concentration of body fluids in a range compatible with life. Question 10 1 / 1 pts What is the primary buffer system for fixed acids? Phosphate Cl– Plasma proteins https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 4/36 2/13/24, 12:58 PM Correct! Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 HCO3– The H+ of fixed acids can be buffered by HCO3– ions and converted to CO2 and H2O (see the previous reaction); the CO2 thus formed is eliminated in exhaled gas. Question 11 1 / 1 pts Which of the following systems is primarily responsible for the buffering of fixed acids? Hb Ammonia Phosphate Correct! HCO3– Most of the added fixed acid is buffered by HCO3– because ventilation continually pulls the reaction to the left. Question 12 1 / 1 pts Which of the following organ systems assist in acid excretion? 1. Kidneys 2. Liver 3. Lungs Correct! 1 and 3 only 2 and 3 only 3 only 2 only The lungs and kidneys are the primary acid-excreting organs. Question 13 1 / 1 pts Which organ system actually excretes H+ from the body? Correct! Kidneys Spleen https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 5/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Lungs Liver The kidneys physically remove H+ from the body. Question 14 1 / 1 pts If the blood PCO2 is high, the kidneys will do which of the following? Excrete less H+ and reabsorb less HCO3–. Correct! Excrete more H+ and reabsorb more HCO3–. Excrete more H+ and reabsorb less HCO3–. Excrete less H+ and reabsorb more HCO3–. If the blood PCO2 is high, creating high levels of H2CO3, then the kidneys excrete greater amounts of H+ and reabsorb all of the tubule filtrate’s HCO3– back into the blood. Question 15 1 / 1 pts What is the primary chemical event in respiratory acidosis? Decrease in blood HCO3– levels Correct! Increase in blood CO2 levels Decrease in blood CO2 levels Increase in blood HCO3– levels A high PaCO2 increases dissolved CO2, lowering the pH: pH HCO3–/PaCO2 where means decreased, means no change, and means increased. Respiratory disturbances causing acidemia are called respiratory acidosis. Question 16 1 / 1 pts What is the primary chemical event in metabolic alkalosis? Increase in blood CO2 levels Decrease in blood CO2 levels https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 6/36 2/13/24, 12:58 PM Correct! Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Increase in blood HCO3– levels Decrease in blood HCO3– levels Processes that increase arterial pH by losing fixed acid or gaining HCO3– produce a condition called metabolic alkalosis. Question 17 1 / 1 pts What is a normal response of the body to a failure in one component of the acid-base regulatory mechanism? Autoregulation Correction Correct! Compensation Homeostasis When any primary acid-base defect occurs, the body immediately initiates a compensatory response. Question 18 1 / 1 pts Compensation for respiratory acidosis occurs through which of the following? Increase in blood CO2 levels Decrease in blood CO2 levels Decrease in blood HCO3– levels Correct! Increase in blood HCO3– levels For example, in hypoventilation (respiratory acidosis), the kidneys restore the pH toward normal by reabsorbing HCO3– into the blood. Question 19 1 / 1 pts Compensation for metabolic acidosis occurs through which of the following? Increase in blood CO2 levels Correct! Decrease in blood CO2 levels https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 7/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Decrease in blood HCO3– levels Increase in blood HCO3– levels If a nonrespiratory (metabolic) process lowers or raises [HCO3–], the lungs compensate by hyperventilating (eliminating CO2) or hypoventilating (retaining CO2), restoring the pH to near normal. Question 20 1 / 1 pts Which of the following accurately describes compensation for acid-base disorders? Lungs take hours to days to compensate for metabolic disorders. Respiratory compensation is always complete. Correct! Kidneys take hours to days to compensate for respiratory disorders. Renal compensation is always complete. The lungs normally compensate quickly for metabolic acid-base defects because ventilation can change the PaCO2 within seconds. The kidneys require more time to retain or excrete significant amounts of HCO3–, and thus compensate for respiratory defects at a much slower pace. Question 21 1 / 1 pts An increase in the H+ ion concentration [H+] of the blood due only to an increase in the arterial PCO2 (hypercapnia) best describes which of the following? Correct! Respiratory acidosis Metabolic alkalosis Metabolic acidosis Respiratory alkalosis For example, if the pH was lower than 7.35 (denoting an acidosis) and the PaCO2 was higher than 45 mm Hg, according to the H-H equation, the high PaCO2 would indeed lower the pH (i.e., produce an acidosis). Therefore, the respiratory system is at least in part, if not entirely, responsible for the acidosis. Question 22 1 / 1 pts An ABG result shows the pH to be 7.56 and the HCO3– to be 23 mEq/L. Which of the following is the most likely disorder? https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 8/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Metabolic alkalosis Respiratory acidosis Metabolic acidosis Correct! Respiratory alkalosis If HCO3– is in the normal range in the presence of alkalosis, then the alkalosis probably is of respiratory origin. Question 23 1 / 1 pts An ABG result shows pH of 7.35, PaCO2 of 30 mm Hg, and HCO3– of 18 mEq/L. Which of the following is the patient’s most likely primary disorder? Metabolic alkalosis Correct! Metabolic acidosis Respiratory alkalosis Respiratory acidosis In cases in which compensation has occurred, if the pH is on the acidic side of 7.40 (7.35 to 7.39), the component that would cause an acidosis (either increased PaCO2 or decreased plasma HCO3–) is generally the primary cause of the original acid-base imbalance. Question 24 1 / 1 pts Which of the following clinical findings would you expect in a fully compensated respiratory acidosis? 1. Elevated HCO3– 2. pH below 7.35 3. pH between 7.35 and 7.39 4. Elevated PO2 1, 3, and 4 only Correct! 1 and 3 only 2 and 2 only 1, 2 and 4 only This completely compensated respiratory acidosis is characterized by the same originally observed high PaCO2, a pH that is now in the 7.35 to 7.39 range, and a plasma [HCO3–] that is greater than it was before complete compensation took place. https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 9/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Question 25 1 / 1 pts In the face of uncompensated respiratory acidosis, which of the following blood gas abnormalities would you expect to encounter? 1. Decreased pH 2. Increased HCO3– 3. Increased PCO2 4. Increased pH Correct! 1 and 3 only 2, 3, and 4 only 1, 2, and 4 only 2 and 3 only If hypercapnia is uncompensated, respiratory acidosis occurs with a low pH, a high PaCO2, and a normal or slightly high [HCO3–]. In this instance, the slightly high [HCO3–] is not a sign that the kidneys have started compensatory activity; it merely reflects the effect of CO2 hydration reaction on [HCO3–]. Question 26 1 / 1 pts How is acute respiratory acidosis accomplished? Correct! By increasing alveolar ventilation By increasing HCO3– reabsorption By decreasing alveolar ventilation By decreasing HCO3– reabsorption The main goal in correcting respiratory acidosis is to improve alveolar ventilation. This may entail various respiratory care modalities ranging from bronchial hygiene and lung expansion techniques to endotracheal intubation and mechanical ventilation. Question 27 1 / 1 pts A decrease in the H+ ion concentration [H+] of the blood caused by a low PaCO2 best describes which of the following? Metabolic acidosis Correct! Respiratory alkalosis Respiratory acidosis https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 10/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Metabolic alkalosis Any physiologic process that lowers the arterial PCO2 (7.45) produces respiratory alkalosis. Question 28 1 / 1 pts Which one is NOT cause of respiratory alkalosis? Correct! Extreme obesity Restrictive pulmonary disease Hypoxia acute asthma Extreme obesity causes respiratory acidosis Question 29 1 / 1 pts Compensation for respiratory alkalosis occurs through which of the following? Renal reabsorption of HCO3– Renal excretion of H+ Renal excretion of NH4+ Correct! Renal excretion of HCO3– The kidneys compensate for respiratory alkalosis by excreting HCO3– in the urine. Question 30 1 / 1 pts In a patient with partially compensated respiratory alkalosis, which of the following blood gas abnormalities would you expect to encounter? 1. Decreased pH 2. Decreased HCO3– 3. Decreased PCO2 4. Increased pH 1 and 3 only Correct! 2, 3, and 4 https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 11/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 2 and 4 only 1, 2, and 4 only Partly compensated respiratory alkalosis is characterized by a low PaCO2, a low [HCO3–], and an alkaline pH—still not quite down in the normal range. Question 31 1 / 1 pts What is a normal anion gap range? Correct! 9 to 14 mEq/L 24 to 26 mEq/L 3 to 5 mEq/L 6 to 8 mEq/L A value of 140 mEq/L for Na+, 105 mEq/L for Cl–, and 24 mEq/L for HCO3–, yielding an anion gap of 11 mEq/L (140 mEq/L – [105 mEq/L + 24 mEq/L] = 11 mEq/L). The normal anion gap range is 9 to 14 mEq/L. Question 32 1 / 1 pts What is the main compensatory mechanism for metabolic acidosis? Hypoventilation Retention of CO2 Correct! Hyperventilation Excretion of HCO3– Hyperventilation is the main compensatory mechanism for metabolic acidosis. The increased plasma [H+] of metabolic acidosis is buffered by plasma HCO3–, reducing the plasma [HCO3–], and thus the pH. Uncompensated metabolic acidosis suggests that a ventilatory defect must exist. Question 33 1 / 1 pts In a patient with Kussmaul’s respirations, what acid-base disturbance would you expect to see? Correct! Metabolic acidosis https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 12/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Metabolic alkalosis Respiratory alkalosis Respiratory acidosis With severe diabetic ketoacidosis, a very deep, gasping type of breathing develops, called Kussmaul’s respiration. Question 34 1 / 1 pts What is the treatment may be indicated. for metabolic acidosis? Charcoal Glucose Correct! NaHCO3– infusion Insulin In cases of metabolic acidosis, intravenous infusion of sodium bicarbonate (NaHCO3–) may be indicated. Question 35 1 / 1 pts What compensates for a metabolic alkalosis? Renal excretion of HCO3– Correct! Hypoventilation Hyperventilation Renal retention of H+ The expected compensatory response to metabolic alkalosis is hypoventilation (CO2 retention). Question 36 1 / 1 pts Based on the following ABG results, what is the most likely acid-base diagnosis? pH = 7.43, PCO2 = 39 mm Hg, HCO3– = 25.1 mEq/L Partially compensated metabolic acidosis https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 13/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Fully compensated metabolic acidosis Fully compensated respiratory alkalosis Correct! Acid-base status within normal limits As all the ABG values are within normal limits the gas must be normal. Question 37 1 / 1 pts Based on the following ABG results, what is the most likely acid-base diagnosis? pH = 7.62, PCO2 = 41 mm Hg, HCO3– = 40.9 mEq/L Fully compensated metabolic alkalosis Partially compensated metabolic alkalosis Correct! Acute (uncompensated) metabolic alkalosis Acute (uncompensated) respiratory alkalosis The patient is alkalotic (pH >7.35). This can be caused by an elevated HCO3– or a low PCO2. In this question the HCO3– is elevated. If compensation were present the PCO2 would have to be elevated. As it is normal, this is an uncompensated metabolic alkalosis. Question 38 1 / 1 pts Based on the following ABG results, what is the most likely acid-base diagnosis? pH = 7.43, PCO2 = 20 mm Hg, HCO3– = 12.6 mEq/L Fully compensated metabolic acidosis Partially compensated respiratory alkalosis Acute (uncompensated) respiratory alkalosis Correct! Fully compensated respiratory alkalosis The patient’s pH is normal so either the gas is normal or fully compensated. As the PCO2 and HCO3– are both low, a fully compensated state exists. As the pH is on the high side of normal the fully compensated disorder would be alkalosis. This would be caused by a low PCO2 or a high HCO3–. In this case a low PCO2. The low HCO3– is compensating for this respiratory alkalosis. Question 39 https://canvas.americancareercollege.edu/courses/8424/quizzes/48646 1 / 1 pts 14/36 2/13/24, 12:58 PM Homework 6 Ch13 Assessment of Acid-Base, Ch14 Oxygenation and Lung Protective: RCP200 Cardiopulmonary Anatomy & Physiology AOS20231212 RT2310-2 Based on the following ABG results, what is the most likely acid-base diagnosis? pH = 6.89, PCO2 = 24 mm Hg, HCO3– = 4.7 mEq/L Correct! Partially compensated metabolic acidosis Acute (uncompensated) metabolic acidosis Partially compensated respiratory acidosis Acute (uncompensated) respiratory acidosis The patient is acidotic (pH