NU373 Week 2 EAQ Evolve Elsevier: Arterial Blood Gas (ABG)

Which statements by the student nurse are accurate about the manifestation of alkalosis in the central nervous system? Select all that apply. o "The client's Chvostek sign would be negative." o "The client's Trousseau sign would be positive." o "The client would be suffering from paresthesias." o "The client would show signs of anxiety and irritability." o "The client's central nervous system should have decreased activity."

o "The client's Trousseau sign would be positive." o "The client would be suffering from paresthesias." o "The client would show signs of anxiety and irritability." · If clients suffer from the alkalosis, central nervous system activity increases, which manifests as paresthesias, positive Trousseau sign, anxiety, and irritability. The Chvostek sign would also be positive, not negative.

A client is in a state of uncompensated acidosis. Which approximate arterial blood pH does the nurse expect the client to have? o 7.20 o 7.35 o 7.45 o 7.48

o 7.20 · The pH of blood is maintained within the narrow range of 7.35 to 7.45. When there is an increase in hydrogen ions, the respiratory, buffer, and renal systems attempt to compensate to maintain the pH. If compensation is not successful, acidosis results and is reflected in a lower pH.

An arterial blood gas report indicates that pH is 7.25, Pco2 is 60 mm Hg, and HCO3 is 26 mEq/L (26 mmol/L). Which client is most likely to exhibit these blood gas results? o A client with pulmonary fibrosis o A client with uncontrolled type 1 diabetes o A client who has been vomiting for 3 days o A client who takes sodium bicarbonate for indigestion

o A client with pulmonary fibrosis · The low pH and elevated Pco2 are consistent with respiratory acidosis, which can be caused by pulmonary fibrosis, which impedes the exchange of oxygen and carbon dioxide in the lung. A client with uncontrolled type 1 diabetes most likely will experience metabolic acidosis from excess ketone bodies in the blood. A client who has been vomiting for 3 days most likely will experience metabolic alkalosis from the loss of hydrochloric acid from vomiting. A client who takes sodium bicarbonate for indigestion most likely will experience metabolic alkalosis from an excess of base bicarbonate.

Which assessment finding in a laboring client indicates respiratory alkalosis? o A change in the respiratory rate o A tingling sensation in the hands o Periodic changes in the fetal heart rate o A pulse oximetry reading of less than 98%

o A tingling sensation in the hands · The presence of a tingling sensation in the hands indicates respiratory alkalosis due to a decrease in carbon dioxide. A change in respiratory rate is incorrect because although such a change may contribute to respiratory alkalosis, it is not evidence of an increase in pH. In the presence of maternal respiratory alkalosis, chemical changes in maternal erythrocytes facilitate oxygen release to the fetus, which assists in maintaining a normal fetal heart rate. A pulse oximetry reading of 98% is incorrect because this is a normal finding.

When the nurse is reviewing a client's arterial blood gas results, which finding is consistent with respiratory alkalosis? o An elevated pH, elevated partial pressure of carbon dioxide (PCO2) o A decreased pH, elevated PCO2 o An elevated pH, decreased PCO2 o A decreased pH, decreased PCO2

o An elevated pH, decreased PCO2 · In respiratory alkalosis the pH level is elevated because of loss of hydrogen ions; the PCO2 level is low because carbon dioxide is lost through hyperventilation. An elevated pH and elevated PCO2 are partially compensated metabolic alkalosis. A decreased pH and elevated PCO2 are respiratory acidosis. A decreased pH and decreased PCO2 are metabolic acidosis with some compensation.

A high school student arrives at the local blood drive center to donate blood for the first time. As the site is being prepared for needle insertion, the student becomes agitated, starts to hyperventilate, and complains of dizziness and tingling of the hands. Which would the nurse instruct the student to do? o Breathe into cupped hands. o Pant using rapid, shallow breaths. o Use a rapid deep-breathing pattern. o Hold the breath for as long as possible.

o Breathe into cupped hands. · Breathing into cupped hands allows carbon dioxide to reenter the lungs, which will increase the serum bicarbonate level, relieving the respiratory alkalosis that is occurring as a result of hyperventilation. A rapid breathing pattern will exacerbate the respiratory alkalosis because excess carbon dioxide will continue to be expelled with rapid breathing, lowering the serum bicarbonate level. A fast deep-breathing pattern will exacerbate the respiratory alkalosis because excess carbon dioxide will continue to be expelled with rapid breathing, lowering the serum bicarbonate level. A person who is experiencing a panic attack will not be able to hold his or her breath.

Which complication would the nurse prevent by addressing the needs of a hyperventilating client? o Cardiac arrest o Carbonic acid deficit o Reduction in serum pH o Excess oxygen saturation

o Carbonic acid deficit · Hyperventilation causes excessive loss of carbon dioxide, leading to carbonic acid deficit and respiratory alkalosis. Cardiac arrest is unlikely; the client may experience dysrhythmias but eventually will lose consciousness and begin breathing regularly. Hyperventilation causes alkalosis, so the pH is increased rather than reduced. Excess oxygen saturation cannot occur; normal oxygen saturation of hemoglobin is 95% to 98%.

After a gastrectomy, a client has a nasogastric tube set to low continuous suction. The client begins to hyperventilate. How would the nurse anticipate that this breathing pattern will alter the client's arterial blood gases? o Increase the PO2 level o Decrease the pH level o Increase the HCO3 level o Decrease the pCO2 level

o Decrease the pCO2 level · Hyperventilation results in increased elimination of carbon dioxide from the blood. The PO2 level is not affected. The pH level will increase. The carbonic acid level will decrease.

On admission to an intensive care unit, a client is diagnosed with compensated metabolic acidosis. The nurse expects which assessment finding? o Muscle twitching o Mental instability o Deep and rapid respirations o Tachycardia and cardiac dysrhythmias

o Deep and rapid respirations · Deep, rapid respirations are an adaptation to a decreased serum pH. Carbonic acid dissociates in the lungs to hydrogen ions and carbon dioxide, which helps increase the serum pH. Muscle twitching results from low serum calcium (hypocalcemia), not compensated metabolic acidosis. Mental confusion does not occur in compensated acidosis; confusion can occur in uncompensated metabolic acidosis. Tachycardia and cardiac dysrhythmias are associated with hyperthyroidism, not compensated metabolic acidosis.

Which diagnosis is a client most likely to have who has an arterial blood gas report indicating that pH is 7.25, PCO2 is 35 mm Hg, and HCO3 is 20 mEq/L (20 mmol/L)? o Panic attack o Persistent vomiting o Diabetic ketoacidosis o Advanced emphysema

o Diabetic ketoacidosis · The low pH and bicarbonate levels are consistent with metabolic acidosis, which can be caused by excess ketones, a result of diabetic ketoacidosis. Persistent vomiting will cause metabolic alkalosis and high HCO3 from loss of gastric hydrochloric acid. Panic attacks lead to hyperventilation and respiratory alkalosis with low PCO2. Advanced emphysema causes elevated PCO2 and respiratory acidosis.

Which early signs of respiratory acidosis would the nurse expect the client with a restrictive airway disease to exhibit? Select all that apply. o Headache o Irritability o Restlessness o Hypertension o Lightheadedness

o Headache o Irritability o Restlessness · Headache is a symptom of cerebral hypoxia associated with early respiratory acidosis. Irritability is a sign of cerebral hypoxia associated with early respiratory acidosis. Restlessness is a sign of cerebral hypoxia associated with early respiratory acidosis. Hypotension, not hypertension, is a key feature of acidosis. Lightheadedness is a symptom of respiratory alkalosis, not acidosis.

A client appears anxious, exhibiting 40 shallow respirations per minute. The client reports dizziness, light-headedness, and tingling sensations of the fingertips and around the lips. The nurse concludes that the client's symptoms are most likely related to which condition? o Eupnea o Hyperventilation o Kussmaul respirations o Carbon dioxide intoxication

o Hyperventilation · The client is hyperventilating and blowing off excessive carbon dioxide, which leads to these adaptations; if uninterrupted, this can result in respiratory alkalosis. Eupnea is normal, quiet breathing; the client has shallow, rapid breathing. Kussmaul respirations are deep, gasping respirations associated with diabetic acidosis and coma. These adaptations are related to a decreased carbon dioxide level in the body.

Which statement explains why metabolic acidosis develops with kidney failure? o Inability of the renal tubules to secrete hydrogen ions and conserve bicarbonate o Depressed respiratory rate due to metabolic wastes, causing carbon dioxide retention o Inability of the renal tubules to reabsorb water to dilute the acid contents of blood o Impaired glomerular filtration, causing retention of sodium and metabolic waste products

o Inability of the renal tubules to secrete hydrogen ions and conserve bicarbonate · Bicarbonate buffering is limited, hydrogen ions accumulate, and acidosis results. The rate of respirations increases in metabolic acidosis to compensate for a low pH. The fluid balance does not significantly alter the pH. The retention of sodium ions is related to fluid retention and edema rather than to acidosis.

When arterial blood gas results for an alert client who is in the postanesthesia care unit (PACU) after abdominal surgery are pH 7.37, PaCO2 42 mm Hg (5.59 kPa), HCO3 25 mEq (25 mmol/L), PaO2 65 mm Hg (8.64 kPa), and SaO2 90% (0.90), which action would the nurse take? o Increase the oxygen flow rate. o Insert an oropharyngeal airway. o Suction the oropharynx and upper trachea. o Prepare to transfer the client out of the PACU.

o Increase the oxygen flow rate. · Because the arterial blood gases indicate mild hypoxemia and normal acid-base balance, the nurse would increase the oxygen flow rate. Insertion of an oropharyngeal airway is unnecessary and contraindicated in an alert client because it will activate the gag reflex. There is no indication that the client needs suctioning. Because the client is hypoxemic, further monitoring and anesthesia recovery are needed before transferring from the PACU.

An arterial blood gas report indicates the client's pH is 7.25, PCO2 is 35 mm Hg, and HCO3 is 20 mEq/L. Which disturbance would the nurse identify based on these results? o Metabolic acidosis o Metabolic alkalosis o Respiratory acidosis o Respiratory alkalosis

o Metabolic acidosis · A low pH and low bicarbonate level are consistent with metabolic acidosis. The pH indicates acidosis, not alkalosis. The CO2 concentration is within normal limits, which is inconsistent with respiratory acidosis; it is elevated with respiratory acidosis.

Which initial change in acid-base balance will the nurse expect when a client is in the progressive stage of shock? o Metabolic acidosis o Metabolic alkalosis o Respiratory acidosis o Respiratory alkalosis

o Metabolic acidosis · Metabolic acidosis occurs during the progressive stage of shock as a result of accumulated lactic acid. Metabolic alkalosis cannot occur with the buildup of lactic acid. As shock progresses, eventually respiratory acidosis can result from decreased respiratory function in late shock. Respiratory alkalosis may occur as a result of hyperventilation during early shock.

A 4-month-old infant is brought to the emergency department after 2 days of diarrhea. The infant is listless and has sunken eyeballs, a depressed anterior fontanel, and poor tissue turgor. Breathing is deep, rapid, and unlabored. Stools are liquid and there has been no obvious urine output. Which problem would the nurse be concerned about? o Kidney failure o Mild dehydration o Metabolic acidosis o Respiratory alkalosis

o Metabolic acidosis · Metabolic acidosis occurs with loss of alkaline fluid through diarrhea and is manifested by lethargy and Kussmaul breathing; all of the assessments indicate severe dehydration. The infant has not urinated because excessive amounts of fluid have been lost in the loose stools; this indicates that the kidneys are functioning by compensating for the fluid loss. All data indicate a severe, not mild, fluid volume deficiency. Respiratory alkalosis is caused by an excessive loss of carbon dioxide, not alkaline loss from diarrhea.

A 3-month-old infant with a 3-day history of diarrhea has an arterial blood gas drawn. Which acid-base imbalance would the nurse suspect? o Metabolic acidosis o Metabolic alkalosis o Respiratory acidosis o Respiratory alkalosis

o Metabolic acidosis · The pH indicates acidosis, not alkalosis; the HCO3- level is further from the expected range than is the Pco2 level, indicating a metabolic, not respiratory, origin (losses from diarrhea).

A critically ill 5-year-old child exhibits Kussmaul respirations. Which would the nurse suspect may be causing an increasing acid-base imbalance? o Metabolic alkalosis caused by an increase in base bicarbonate o Respiratory alkalosis caused by excess carbon dioxide (CO2) output o Respiratory acidosis caused by an accumulation of CO2 o Metabolic acidosis caused by a concentration of cations in body fluids

o Metabolic acidosis caused by a concentration of cations in body fluids · Metabolic acidosis results from an excess concentration of hydrogen cations. The kidneys cannot convert ammonium to ammonia, and there is inadequate base bicarbonate to maintain an appropriate acid-base balance. With Kussmaul respirations there is an excess of hydrogen ions, the opposite of an excess of base bicarbonate. Carbonic acid blown off as CO2 is a compensatory mechanism to counter the present metabolic acidosis. There is an excess of hydrogen ions from a metabolic problem rather than an excess of carbonic acid resulting from retained CO2.

The laboratory data for a client with prolonged vomiting reveal arterial blood gases of pH 7.51, Pco2 of 45 mm Hg, HCO3 of 58 mEq/L (59 mmol/L), and a serum potassium level of 3.8 mEq/L (3.8 mmol/L). The nurse concludes that the findings support which diagnosis? o Hypocapnia o Hyperkalemia o Metabolic alkalosis o Respiratory acidosis

o Metabolic alkalosis · Elevated plasma pH and elevated bicarbonate levels support metabolic alkalosis. The arterial carbon dioxide level of 45 mm Hg is within the expected value of 35 mm Hg to 45 mm Hg; no hypocapnia is present. The client's serum potassium level is within the expected level of 3.5 mEq/L to 5 mEq/L (3.5-5 mmol/L). With respiratory acidosis the pH will be less than 7.35 and the Pco2 will be elevated.

A client arrives in the emergency department with epigastric pain and prolonged vomiting. Assessment findings include rapid and shallow respirations, dry and flushed skin, weakness, and lethargy. Which is the primary nursing concern? o Acute pain o Risk for injury o Metabolic alkalosis o Ineffective breathing

o Metabolic alkalosis · Prolonged vomiting results in fluid loss and acid (hydrochloric) loss; the client's symptoms reflect dehydration and metabolic alkalosis. Although it is important to address the client's pain, the fluid and electrolyte/acid/base imbalance must be addressed first because it can be life threatening. Although risk for injury is a potential problem, the priority is the fluid and electrolyte/acid/base problem. The ineffective breathing pattern most likely is caused by the metabolic alkalosis; the fluid and electrolyte/acid/base imbalance is a higher priority and must be addressed first.

A client is hospitalized after 4 days of epigastric pain, nausea, and vomiting. The nurse reviews the laboratory test results: plasma pH 7.51, pCO2 50 mm Hg, bicarbonate 58 mEq/L (58 mmol/L), chloride 55 mEq/L (55 mmol/L), sodium 132 mEq/L (132 mmol/L), and potassium 3.8 mEq/L (3.8 mmol/L). Which condition does the nurse determine the results indicate? o Hypernatremia o Hyperchloremia o Metabolic alkalosis o Respiratory acidosis

o Metabolic alkalosis · The normal plasma pH value is 7.35 to 7.45; the client is in alkalosis. The normal plasma bicarbonate value is 23 to 25 mEq/L (23-25 mmol/L); the client has an excess of base bicarbonate, indicating a metabolic cause for the alkalosis. The normal plasma sodium value is 135 to 145 mEq/L (135-145 mmol/L); the client has hyponatremia. The normal plasma chloride value is 95 to 105 mEq/L (95-105 mmol/L); the client has hypochloremia because of vomiting of gastric secretions. With respiratory acidosis, the pH is decreased to less than 7.35.

The nurse is caring for a client with the following arterial blood gas (ABG) values: PO2 89 mm Hg, PCO2 35 mm Hg, and pH of 7.37. These findings indicate that the client is experiencing which condition? o Respiratory alkalosis o Poor oxygen perfusion o Normal acid-base balance o Compensated metabolic acidosis

o Normal acid-base balance · All data are within expected limits; PO2 is 80 to 100 mm Hg, PCO2 is 35 to 45 mm Hg, and the pH is 7.35 to 7.45. None of the data are indicators of fluid balance, but of acid-base balance. Oxygen (PO2) is within the expected limits of 80 to 100 mm Hg. With respiratory alkalosis, the blood pH is greater than 7.45 and the PCO2 is greatly decreased. With metabolic acidosis, the pH is less than 7.35.

What does the nurse consider to be the priority nursing intervention for a client on diuretic therapy who has developed metabolic alkalosis? o Preventing falls o Monitoring electrolytes o Administering antiemetics o Adjusting the diuretic therapy

o Preventing falls · A client with alkalosis has hypotension and muscle weakness, which increases the risk for injury due to falls; therefore, to prevent injury, the priority nursing care is to prevent falls. Monitoring electrolytes daily until they return to normal is not the priority nursing care. Antiemetics are prescribed for vomiting and are given low priority. Once the client is protected from the risk for injury, diuretic therapy is adjusted.

A client with chronic obstructive pulmonary disease (COPD) has a blood pH of 7.25 and a partial pressure of carbon dioxide (PCO2) of 60 mm Hg. Which complication would the nurse suspect the client is experiencing? o Metabolic acidosis o Metabolic alkalosis o Respiratory acidosis o Respiratory alkalosis

o Respiratory acidosis · The pH indicates acidosis; the PCO2 level is the parameter for respiratory function. The expected PCO2 is 40 mm Hg. These results do not indicate a metabolic disorder or indicate respiratory alkalosis.

Which type of acid-base imbalance would the nurse expect in a child admitted with a severe asthma exacerbation? o Metabolic alkalosis caused by excessive production of acid metabolites o Respiratory alkalosis caused by accelerated respirations and loss of carbon dioxide o Respiratory acidosis caused by impaired respirations and increased formation of carbonic acid o Metabolic acidosis caused by the kidneys' inability to compensate for increased carbonic acid formation

o Respiratory acidosis caused by impaired respirations and increased formation of carbonic acid · The restricted ventilation accompanying an asthma attack limits the body's ability to blow off carbon dioxide. As carbon dioxide accumulates in the body fluids, it reacts with water to produce carbonic acid; the result is respiratory acidosis. The problem basic to asthma is respiratory, not metabolic. Respiratory alkalosis is caused by the exhalation of large amounts of carbon dioxide; asthma attacks cause carbon dioxide retention. Asthma is a respiratory problem, not a metabolic one; metabolic acidosis can result from an increase of nonvolatile acids or from a loss of base bicarbonate.

The nurse determined a client's arterial blood gases reflected a compensated respiratory acidosis. The pH was 7.34; which additional laboratory value did the nurse consider? o The partial pressure of oxygen (PO2) value is 80 mm Hg. o The partial pressure of carbon dioxide (PCO2) value is 60 mm Hg. o The bicarbonate (HCO3) value is 50 mEq/L (50 mmol/L). o Serum potassium value is 4 mEq/L (4 mmol/L).

o The bicarbonate (HCO3) value is 50 mEq/L (50 mmol/L). · The HCO3 value is elevated. The urinary system compensates by retaining hydrogen (H+) ions, which become part of the bicarbonate ions; the bicarbonate level becomes elevated and increases the pH level to near the expected range. The expected HCO3 value is 21 to 28 mEq/L (21-28 mmol/L), and the expected pH value is 7.35 to 7.45. The body's usual PO2 value is 80 to 100 mm Hg; 80 mm Hg is within the expected range. The body's PCO2 value is 35 to 45 mm Hg; although in compensated respiratory acidosis the PCO2 level may be increased, it is the increased HCO3 level that indicates compensation. A potassium (K+) level of 4 mEq/L (4 mmol/L) is within the expected range of 3.5 to 5 mEq/L (3.5-5 mmol/L); the serum potassium level is not significant in identifying compensated respiratory acidosis.

The arterial blood gases for a client with acute respiratory distress are pH 7.30, PaO2 80 mm Hg (10.64 kPa), PaCO2 55 mm Hg (7.32 kPa), and HCO3 23 mEq/L (23 mmol/L). How would the nurse interpret these findings? o Hypoxemia o Hypocapnia o Compensated metabolic acidosis o Uncompensated respiratory acidosis

o Uncompensated respiratory acidosis · The increased PaCO2 indicates respiratory acidosis and the low pH indicates that the respiratory acidosis is uncompensated. The PaO2 is normal, indicating that the client is not hypoxemic. The elevated PaCO2 indicates hypercapnia. The HCO3 is normal, indicating that there is no metabolic acidosis.

Which blood gas result would the nurse expect an adolescent with diabetic ketoacidosis to exhibit? o pH 7.30, CO2 40 mm Hg, HCO3- 20 mEq/L (20 mmol/L) o pH 7.35, CO2 47 mm Hg, HCO3- 24 mEq/L (24 mmol/L) o pH 7.46, CO2 30 mm Hg, HCO3- 24 mEq/L (24 mmol/L) o pH 7.50, CO2 50 mm Hg, HCO3- 22 mEq/L (22 mmol/L)

o pH 7.30, CO2 40 mm Hg, HCO3- 20 mEq/L (20 mmol/L) · A client in diabetic ketoacidosis will have blood gas readings that indicate metabolic acidosis. The pH will be acidic (7.30), and the HCO3- will be low (20 mEq/L [20 mmol/L]). The normal pH is 7.35 to 7.45; CO2 ranges from 35 to 45 mm Hg, and HCO3- ranges from 22 to 26 (22-26 mmol/L). A pH of 7.35 and a CO2 of 47 mm Hg indicate respiratory acidosis. pH values of 7.46 and 7.50 represent alkalosis, not acidosis.

Which blood gas report most likely reflects the acid-base balance of an infant with severe dehydration? o pH of 7.50 and Pco2 of 34 mm Hg o pH of 7.23 and Pco2 of 70 mm Hg o pH of 7.20 and HCO3- of 20 mEq/L (20 mmol/L) o pH of 7.56 and HCO3- of 30 mEq/L (30 mmol/L)

o pH of 7.20 and HCO3- of 20 mEq/L (20 mmol/L) · Low blood pH and bicarbonate levels indicate metabolic acidosis, which occurs with severe dehydration because the reduced urine output causes retention of hydrogen ions. The other options include findings that indicate respiratory alkalosis, respiratory acidosis, and metabolic alkalosis, respectively.