Acid Base Balance and Cognition (H&I Exam 2)
Characteristic findings of AD relate to changes in the brain's structure and function include:
(1) amyloid plaques, (2) neurofibrillary tangles, (3) loss of connections between neurons, and (4) neuron death.
What is the normal bicarbonate/carbonic acid ratio?
20:1
What is the normal bicarbonate range?
22-26
Delusions are:
False, fixed beliefs based on incorrect perception of reality (not part of a cultural tradition such as religion).
What is the normal PaCO2 range?
35-45
What are the clinical manifestations of respiratory acidosis?
Headache, decreased LOC, hypoventilation (cause of problem), cardiac dysrhythmias, if severe hypotension
What is the normal pH range?
7.35-7.45
What are the risk factors of dementia?
Aging, family history, diabetes, obesity, smoking, cardiac dysrhythmias (e.g. cardiac dysrhythmias), hypertension, hypercholesterolemia, coronary artery disease, and genetic factors.Characteristic findings of AD relate to changes in the brain's structure and function:
What are the possible causes of respiratory alkalosis?
Hyperventilation, acute pain,acute hypoxia, or acute anxiety or emotional distress, or central stimulation of respirations by inflammation from head injury or meningitis
The nurse is caring for a client with diabetic ketoacidosis and documents that the client is experiencing Kussmaul's respirations. Based on this documentation, which did the nurse observe? 1. Respirations that cease for several seconds 2. Respirations that are regular but abnormally slow 3. Respirations that are labored and increased in depth and rate 4. Respirations that are abnormally deep, regular, and increased in rate
Answer: 4. Respirations that are abnormally deep, regular, and increased in rate Rationale: Kussmaul's respirations are abnormally deep, regular, and increased in rate. Apnea is described as respirations that cease for several seconds. In bradypnea, respirations are regular but abnormally slow. In hyperpnea, respirations are labored and increased in depth and rate.
Hallucinations are:
false sensory perceptions: Auditory, visual, tactile, gustatory, olfactory Command
What are the possible causes of respiratory acidosis?
COPD, Asthma, Pneumonia, Guillain-Barre Syndrome, Opioid overdose and Pulmonary Edema
Why are there more neurological systems associated with excessive carbonic acid verses bicarbonate?
Carbonic acid crosses the blood brain barrier and changes the CSF pH rapidly. Metabolic acid crosses the blood brain barrier with difficulty and produces fewer neurological manifestations or causes them more slowly.
Clozaril
Interferes with dopamine receptor binding with lack of EPS and tardive dyskinesia; also acts as an adrenergic, cholinergic, histaminergic, serotoninergic antagonist
How long does renal compensation occur vs respiratory compensation?
It takes several days for the renal system to compensate. The respiratory system compensates immediately.
How does the body correct metabolic alkalosis? ( too little metabolic acids)
Renal response: Decreased secretion of H+ (decreased production of NH3) Respiratory response (compensation): Hypoventilation
How does the body correct metabolic acidosis? (too much metabolic acids)
Renal response: Increased secretion of H+ ( increased production of NH3) Respiratory response (compensation): hyperventilation
What is the difference in symptoms of respiratory acidosis and alkalosis on the neurological system?
Respiratory acidosis causes a decreased LOC and respiratory alkalosis causes an initial excitation followed by decreased LOC if the increased pH becomes more severe.
How does the body correct respiratory acidosis? (too much carbonic acid, caused by hypoventilation)
Respiratory response: Hyperventilation Renal response (compensation): Increased secretion of H+ (increased NH3 production)
How does the body correct respiratory alkalosis? (too little carbonic acid, caused by hyperventilation)
Respiratory response: Hypoventilation Renal response (compensation): Decreased production of H+ (decreased NH3 production)
True or False. Altered pH can cause dysfunction of cardiac cells and dysrhythmias?
True
What is vascular dementia?
Vascular dementia, also called multiinfarct dementia, is loss of cognitive function resulting from ischemic or hemorrhagic brain lesions caused by cardiovascular disease. This type of dementia is the result of decreased blood supply from narrowing and blocking of arteries that supply the brain.
What type of imbalance can prolonged diarrhea cause?
metabolic acidosis
Ingestion of heartburn medications or baking soda can lead to which type of imbalance?
metabolic alkalosis
What type of pH imbalance does vomiting cause?
metabolic alkalosis
What is the normal base excess range?
-2 to +2 values below -2 indicate too much metabolic acid and values greater than +2 indicate too little metabolic acid
Illusions are:
false sensory interpretations
An anxious preoperative client is at risk for developing respiratory alkalosis. The nurse should assess the client for which signs and symptoms characteristic of this disorder? 1. Headache and tachypnea 2. Hyperactivity and dyspnea 3. Muscle twitches and cyanosis 4. Lightheadedness and paresthesias
Answer: 4. Lightheadedness and paresthesias Rationale: Clinical manifestations of respiratory alkalosis include a decrease in the respiratory rate and depth, headache, lightheadedness, vertigo, mental status changes, paresthesias such as tingling of the fingers and toes, hypokalemia, hypocalcemia, tetany, and convulsions. Options 1, 2, and 3 are not clinical manifestations of respiratory alkalosis.
Low carb diets and fasting predispose patients to which type of imbalance?
Starvation ketoacidosis
Neurofibrillary tangles are:
abnormal collections of twisted protein threads inside nerve cells.
What are the possible causes of metabolic alkalosis?
acute or chronic oliguric renal disease, circulatory shock, infants and elderly are at increased risk due to poor renal function, increased intake of bicarbonate (antacids, baking soda, IV sodium bicarbonate), excessive aldosterone, and vomiting (leads to HCL acid loss and increase bicarbonate retention), hypokalemia (leads to H+ shifting into cells)
What are the clinical manifestations of metabolic acidosis?
decreased LOC, hyperventilation (compensatory mechanism), abdominal pain, nausea and vomiting, and cardiac dysrhythmias
What are the ABG findings of metabolic alkalosis?
pH increased (basic) PaCO2: increased from compensation (acidic) HCO3: increased (basic)
What are the ABG findings of respiratory alkalosis?
pH: increased (basic) PaCO2: decreased (basic) HCO3: decreased if compensated (acidic)
What are the ABG findings of metabolic acidosis?
pH: low or low normal if fully compensated (acidic) PaCO2: decreased from compensation (basic) HCO3: low (acidic)
What are the ABG findings of respiratory acidosis?
pH: low or low normal if fully compensated (acidic) PaCO2: high (acidic) HCO3: increased from compensation (basic)
A nurse is caring for a client who is experiencing metabolic alkalosis. The nurse plans to protect the client's safety knowing the risks of this imbalance, by carefully implementing which prescribed precaution? 1. Contact isolation 2. Seizure precautions 3. Bleeding precautions 4. Neutropenic precautions
Answer: 2. Seizure precautions Rationale: The client with metabolic alkalosis is at risk for tetany and seizures. The nurse would maintain client safety by using seizure precautions with this client. Options 1, 3, and 4 are unnecessary in the care of the client experiencing metabolic alkalosis.
A client is diagnosed with respiratory alkalosis induced by gram-negative sepsis. The nurse should plan to carry out which prescribed measure as the most effective means to treat the problem? 1. Administer prescribed antibiotics. 2. Have the client breathe into a paper bag. 3. Administer antipyretics as needed (on PRN basis). 4. Request a prescription for a partial rebreather oxygen mask.
Answer: 1. Administer prescribed antibiotics. Rationale: The most effective way to treat an acid-base disorder is to treat the underlying cause of the disorder. In this case, the problem is sepsis, which is most effectively treated with antibiotic therapy. Antipyretics will control fever secondary to sepsis but do nothing to treat the acid-base balance. The paper bag and partial rebreather mask will assist the client to rebreathe exhaled carbon dioxide, but again, these do not treat the primary cause of the imbalance.
A nurse is caring for a client who is retaining carbon dioxide (CO2) as a result of an obstructive respiratory disease. The nurse understands that as the client's CO2 level rises, what will occur with the blood pH? 1. Fall 2. Rise 3. Double 4. Remain unchanged
Answer: 1. Fall Rationale: CO2 acts as an acid in the body. A rise in blood CO2 will result in a fall in pH. The other options are incorrect.
What are the clinical manifestations of respiratory alkalosis?
Excitation and belligerence, lightheadedness, unusual behaviors, followed by decrease LOC if severe, perioral and digital paresthesias, carpopedal spasm, tetany, diaphoresis, hyperventilation (cause of problem), cardiac dysrhythmias
What are the clinical manifestations of metabolic alkalosis?
Excitation followed by decreased in LOC if severe, perioral and digital paresthesias, carpopedal spasm, hypoventilation (compensatory mechanism), signs of volume depletion and hypokalemia if present.
A client with a chronic airflow limitation (CAL) is experiencing respiratory acidosis as a complication. A nurse who is trying to enhance the client's respiratory status should avoid which action? 1. Keeping the head of the bed elevated 2. Monitoring the flow rate of supplemental oxygen 3. Assisting the client to turn, cough, and breathe deeply 4. Encouraging the client to breathe slowly and shallowly
Answer: 4. Encouraging the client to breathe slowly and shallowly Rationale: The client with respiratory acidosis is experiencing elevated carbon dioxide levels caused by insufficient ventilation. The nurse would encourage the client to breathe slowly and deeply to expand alveoli and to promote better gas exchange. The actions listed in options 1, 2, and 3 are helpful actions on the part of the nurse.
The nurse is caring for a client with diabetic ketoacidosis and documents that the client is experiencing Kussmaul's respirations. On the basis of this documentation, which pattern did the nurse observe? 1. Respirations that cease for several seconds 2. Respirations that are regular but abnormally slow 3. Respirations that are labored and increased in depth and rate 4. Respirations that are abnormally deep, regular, and increased in rate
Answer: 4. Respirations that are abnormally deep, regular, and increased in rate Rationale: Kussmaul's respirations are abnormally deep, regular, and increased in rate. Apnea is described as respirations that cease for several seconds. In bradypnea, respirations are regular but abnormally slow. In hyperpnea, respirations are labored and increased in depth and rate.
A client is being treated for metabolic acidosis with medication therapy and other measures. The nurse should plan to monitor the results of which electrolyte, which could dramatically decline with effective treatment of the acidosis? 1. Sodium 2. Potassium 3. Magnesium 4. Phosphorus
Answer: 2. Potassium Rationale: The serum potassium level tends to rise with metabolic acidosis. This is because potassium moves out of the cells and into the bloodstream. When acidosis is corrected with treatment, the potassium will shift back into the cellular compartment. This can cause a rapid drop in the serum potassium level. Because of the effects of potassium on the heart, this electrolyte should be monitored closely while the client is treated.
A client is determined to be in respiratory alkalosis by blood gas analysis. Which electrolyte disorder should the nurse monitor for that could accompany the acid-base balance? 1. Hypokalemia 2. Hypercalcemia 3. Hypochloremia 4. Hypernatremia
Answer: 1. Hypokalemia Rationale: Clinical manifestations of respiratory alkalosis include tachypnea, hyperpnea, weakness, paresthesias, tetany, dizziness, convulsions, coma, hypokalemia, and hypocalcemia. The clinical picture does not include hypercalcemia, hypochloremia, or hypernatremia.
The nurse caring for a client with an ileostomy understands that the client is most at risk for developing which acid-base disorder? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 1. Metabolic acidosis Rationale: Metabolic acidosis is defined as a total concentration of buffer base that is lower than normal, with a relative increase in the hydrogen ion concentration. This results from loss of buffer bases or retention of too many acids without sufficient bases, and occurs in conditions such as kidney disease; diabetic ketoacidosis; high fat diet; insufficient metabolism of carbohydrates; malnutrition; ingestion of toxins, such as acetylsalicylic acid (aspirin); malnutrition; or severe diarrhea. Intestinal secretions are high in bicarbonate and may be lost through enteric drainage tubes, an ileostomy, or diarrhea. These conditions result in metabolic acidosis. The remaining options are incorrect interpretations and are not associated with the client with an ileostomy.
The nurse plans care for a client with chronic obstructive pulmonary disease (COPD), understanding that the client is most likely to experience what type of acid-base imbalance? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 1. Metabolic acidosis Rationale: Respiratory acidosis is most often caused by hypoventilation in a client with COPD. Other acid-base disturbances can occur in a client with COPD during exacerbation of the disease, but the most likely imbalance is respiratory acidosis. The remaining options are incorrect. COPD is a respiratory condition, not a metabolic one. Respiratory alkalosis is associated with hyperventilation.
A client with diabetes mellitus has a blood glucose level on admission of 596 mg/dL. The nurse should anticipate that this client could be experiencing which type of acid-base imbalance? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 1. Metabolic acidosis Rationale: Diabetes mellitus can lead to metabolic acidosis. When the body does not have sufficient circulating insulin, the blood glucose level rises while the cells of the body use all available glucose and then break down glycogen and fat for fuel. The by-products of fat metabolism are acidotic, leading to the complication called diabetic ketoacidosis.
A client with diabetes mellitus has a blood glucose level of 644 mg/dL. The nurse should develop a plan of care because the client is at risk for the development of which type of acid-base imbalance? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 1. Metabolic acidosis Rationale: Diabetes mellitus can lead to metabolic acidosis. When the body does not have sufficient circulating insulin, the blood glucose level rises. At the same time, the cells of the body use all available glucose. The body then breaks down glycogen and fat for fuel. The by-products of fat metabolism are acidotic, potentially leading to the condition known as diabetic ketoacidosis. Options 2, 3, and 4 are incorrect.
A nurse is admitting a client with a diagnosis of Guillain-Barré syndrome to the hospital. The nurse knows that if the disease is severe enough, the client will be at risk for which acid-base imbalance? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 3. Respiratory acidosis Rationale: Guillain-Barré is a neuromuscular disorder in which the client may experience weakening or paralysis of the muscles used for respiration. This could cause the client to retain carbon dioxide, leading to respiratory acidosis and ventilatory failure as the paralysis develops. Therefore, options 1, 2, and 4 are incorrect.
A client has a prescription for a set of arterial blood gas (ABGs) samples to be drawn on room air. The client currently is receiving oxygen by nasal cannula at a delivery rate of 3 L/min. After reading the prescription, the nurse should take which action? 1. Remove the nasal cannula for 15 minutes; then have the ABG samples drawn. 2. Change the nasal cannula to a shovel face mask; then have the ABG samples drawn. 3. Leave the nasal cannula in place for 15 minutes; then have the ABG samples drawn. 4. Change the nasal cannula to a Venturi face mask; then have the ABG samples drawn.
Answer: 1. Remove the nasal cannula for 15 minutes; then have the ABG samples drawn. Rationale: The client should have oxygen supplementation removed for at least 15 minutes before ABGs are drawn if the client has a prescription for the ABGs to be drawn on room air. This allows time for the client's system to equilibrate so that the ABG results will accurately reflect ventilatory status without the supplemental oxygen. This prescription may be given when the health care provider is trying to decide whether to discontinue oxygen therapy, and it allows staff to observe how the client tolerates oxygen removal. Therefore the remaining options are incorrect.
A client is scheduled for blood to be drawn from the radial artery for an arterial blood gas determination. Before the blood is drawn, an Allen's test is performed to determine the adequacy of which? 1. Ulnar circulation 2. Carotid circulation 3. Femoral circulation 4. Popliteal circulation
Answer: 1. Ulnar circulation Rationale: Before radial puncture is performed to obtain an arterial specimen for determination of arterial blood gases, an Allen's test should be performed to determine the adequacy of the ulnar circulation. Failure to determine the presence of adequate collateral circulation could result in severe ischemic injury to the hand if damage to the radial artery occurs with arterial puncture. Options 2, 3, and 4 are incorrect because these anatomical areas are not associated with adequate circulation to the hand.
A client has a prescription for arterial blood gas (ABG) analysis on radial artery specimens. The nurse ensures that which intervention has been performed or tested before the ABG specimens are drawn? 1. Allen's test 2. Goodell's sign 3. Babinski reflex 4. Brudzinski's sign
Answer: 1. Allen's test Rationale: Before radial artery puncture for obtaining a blood sample for ABG analysis, an Allen test should be performed to determine adequate ulnar circulation. Failure to determine the presence of adequate collateral circulation could result in severe ischemic injury to the hand if damage to the radial artery occurs with arterial puncture. Goodell's sign is used during pregnancy and indicates a softening of the cervix at the beginning of the second month of pregnancy. The Babinski reflex is checked by stroking upward on the sole of the foot. Brudzinski's sign is nuchal rigidity on bending the head down toward the chest.
The nurse is performing a change-of-shift assessment on a client. The client had an arterial blood gas specimen drawn during an admission work-up on the previous day and has a hematoma at the puncture site. What is the priority nursing intervention? 1. Perform the Allen's test. 2. Apply a warm compress. 3. Administer the antidote for heparin. 4. Notify the hospital laboratory supervisor.
Answer: 2. Apply a warm compress. Rationale: The application of a warm compress enhances the absorption of blood in the hematoma. Allen's test is performed before the collection of the specimen to assess collateral blood flow. Heparinized syringes are used for the collection of an arterial blood gas but no heparin is administered to a client. The antidote for heparin is not administered at this time unless prescribed. The laboratory department is not responsible for collecting the ABG specimen. Additionally, there is no useful reason to notify the hospital laboratory supervisor.
A client has been diagnosed with metabolic alkalosis as a result of excessive antacid use. The nurse should monitor this client, expecting to note which signs/symptoms? 1. Disorientation and dyspnea 2. Decreased respiratory rate and depth 3. Drowsiness, headache, and tachypnea 4. Tachypnea, dizziness, and paresthesias
Answer: 2. Decreased respiratory rate and depth Rationale: A client with metabolic alkalosis is likely to exhibit decreased respiratory rate and depth as a compensatory mechanism. A client with metabolic acidosis would display the symptoms noted in option 3. The client with respiratory acidosis and alkalosis would display the symptoms noted in options 1 and 4, respectively.
A nurse is caring for a client who overdosed on acetylsalicylic acid (aspirin) 24 hours ago. The nurse should expect to note which findings associated with an anticipated acid-base disturbance? 1. Disorientation and dyspnea 2. Drowsiness, headache, and tachypnea 3. Tachypnea, dizziness, and paresthesias 4. Decreased respiratory rate and depth, cardiac irregularities
Answer: 2. Drowsiness, headache, and tachypnea Rationale: The client who ingests a large amount of acetylsalicylic acid (aspirin) is at risk for developing metabolic acidosis 24 hours later. If metabolic acidosis occurs, the client is likely to exhibit drowsiness, headache, and tachypnea. In the very early hours following aspirin overdose, the client may exhibit respiratory alkalosis as a compensatory mechanism. However, by 24 hours post-overdose, the compensatory mechanism fails and the client reverts to metabolic acidosis. The client with metabolic alkalosis (option 4) is likely to experience cardiac irregularities and a compensatory decreased respiratory rate and depth. Options 1 and 3 indicate respiratory acidosis and alkalosis, respectively.
The client tells the nurse that he ingests large amounts of oral antacids on a daily basis. The nurse plans care knowing that the excessive use of oral antacids containing bicarbonate can result in which acid-base disturbance? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 2. Metabolic alkalosis Rationale: Increases in base components occur as a result of oral or parenteral intake of bicarbonates, carbonates, acetates, citrates, or lactates. Excessive use of oral antacids containing bicarbonate can cause a metabolic alkalosis. The remaining acid-base disturbances are incorrect.
The nurse is caring for a client with a nasogastric tube that is attached to low suction. The nurse monitors the client, knowing that the client is at risk for which acid-base disorder? 1. Metabolic acidosis 2. Metabolic alkalosis 3. Respiratory acidosis 4. Respiratory alkalosis
Answer: 2. Metabolic alkalosis Rationale: Metabolic alkalosis is defined as a deficit or loss of hydrogen ions or acids or an excess of base (bicarbonate) that results from the accumulation of base or from a loss of acid without a comparable loss of base in the body fluids. This occurs in conditions resulting in hypovolemia, the loss of gastric fluid, excessive bicarbonate intake, the massive transfusion of whole blood, and hyperaldosteronism. Loss of gastric fluid via nasogastric suction or vomiting causes metabolic alkalosis as a result of the loss of hydrochloric acid. The remaining options are incorrect interpretations.
The nurse is caring for a client who is on a mechanical ventilator. Blood gas results indicate a pH of 7.50 and a Pco2 of 30 mm Hg. The nurse has determined that the client is experiencing respiratory alkalosis. Which laboratory value would most likely be noted in this condition? 1. Sodium level of 145 mEq/L 2. Potassium level of 3.0 mEq/L 3. Magnesium level of 2.0 mg/dL 4. Phosphorus level of 4.0 mg/dL
Answer: 2. Potassium level of 3.0 mEq/L Rationale: Respiratory alkalosis is defined as a deficit of carbonic acid or a decrease in hydrogen ion concentration that results from the accumulation of base or from a loss of acid without a comparable loss of base in the body fluids. This occurs in conditions that cause overstimulation of the respiratory system. Clinical manifestations of respiratory alkalosis include lethargy, lightheadedness, confusion, tachycardia, dysrhythmias related to hypokalemia, nausea, vomiting, epigastric pain, and numbness and tingling of the extremities. All three incorrect options identify normal laboratory values. The correct option identifies the presence of hypokalemia.
The nurse is caring for a client with chronic kidney disease. Arterial blood gas (ABG) results indicate a pH of 7.30, a Pco2 of 32 mm Hg, and a bicarbonate concentration of 20 mEq/L. Which laboratory value should the nurse expect to note? 1. Sodium level of 145 mEq/L 2. Potassium level of 5.2 mEq/L 3. Phosphorus level of 4.0 mg/dL 4. Magnesium level of 2.0 mg/dL
Answer: 2. Potassium level of 5.2 mEq/L Rationale: Interpretation of the ABG indicates metabolic acidosis with partial compensation by the respiratory system. Clinical manifestations of metabolic acidosis include hyperpnea with Kussmaul's respirations; headache; nausea, vomiting, and diarrhea; fruity-smelling breath resulting from improper fat metabolism; central nervous system depression, including mental dullness, drowsiness, stupor, and coma; twitching; and convulsions. Hyperkalemia will occur.
An anxious client is experiencing respiratory alkalosis from hyperventilation caused by anxiety. The nurse should take which action to help the client experiencing this acid-base disorder? 1. Put the client in a supine position. 2. Provide emotional support and reassurance. 3. Withhold all sedative or antianxiety medications. 4. Tell the client to breathe very deeply but more slowly.
Answer: 2. Provide emotional support and reassurance. Rationale: An anxious client benefits from emotional support and reassurance, which in turn reduces anxiety and may lower the respiratory rate. The client may benefit from the administration of a sedative or antianxiety medication if it is prescribed. The client should try to breathe more slowly. Lying supine provides no benefit to the client and may cause problems with breathing.
A client has had an arterial blood gas sample drawn from the radial artery, and the nurse is asked to hold pressure on the site. The nurse should apply pressure for at least how many minute(s)? 1. 1 minute 2. 2 minutes 3. 5 minutes 4. 10 minutes
Answer: 3. 5 minutes Rationale: After blood is drawn for arterial blood gas analysis, continuous pressure must be applied to the site. A radial artery site requires at least 5 minutes of pressure, whereas a femoral artery site requires 10 minutes. A small pressure dressing often is placed on the site after this time period. When the client is receiving anticoagulant therapy, application of pressure for a longer period may be needed.
A nurse is providing care to a client with the following arterial blood gas (ABG) results: pH 7.50; Pao2 90 mm Hg; Paco2 40 mm Hg; and bicarbonate 35 mEq/L. When the nurse notifies the health care provider (HCP) about these levels, the nurse should anticipate receiving which prescription for this client from the HCP? 1. Obtain a serum alcohol level. 2. Obtain a serum salicylate level. 3. Discontinue nasogastric suctioning. 4. Discontinue the client's Fentanyl patch.
Answer: 3. Discontinue nasogastric suctioning. Rationale: The ABG results indicate metabolic alkalosis as the pH and bicarbonate are elevated. Nasogastric suctioning may cause metabolic alkalosis by decreasing the acid components in the stomach. Excess alcohol ingestion and salicylate toxicity may cause metabolic acidosis. Fentanyl (an opioid) may cause respiratory acidosis.
A client is admitted to the hospital 24 hours following an aspirin (acetylsalicylic acid) overdose. The nurse assesses this client for which signs/symptoms, indicating the acid-base disturbance that could occur in the client? 1. Bradypnea, dizziness, and paresthesias 2. Bradycardia, listlessness, and hyperactivity 3. Headache, nausea, vomiting, and diarrhea 4. Restlessness, confusion, and a positive Trousseau's sign
Answer: 3. Headache, nausea, vomiting, and diarrhea Rationale: The client who ingests a large amount of aspirin (acetylsalicylic acid) is at risk for developing metabolic acidosis 24 hours after the poisoning. If metabolic acidosis occurs, the client may exhibit hyperpnea with Kussmaul's respirations, headache, nausea, vomiting, diarrhea, fruity-smelling breath because of improper fat metabolism, central nervous system depression, twitching, convulsions, and hyperkalemia. Shortly after aspirin overdose, the client may exhibit respiratory alkalosis as a compensatory mechanism. By 24 hours post-overdose, however, the compensatory mechanism fails and the client reverts to metabolic acidosis.
The client with a history of lung disease is at risk for developing respiratory acidosis. The nurse assesses this client for which signs/symptoms that are characteristic of this disorder? 1. Bradycardia and hyperactivity 2. Decreased respiratory rate and depth 3. Headache, restlessness, and confusion 4. Bradypnea, dizziness, and paresthesias
Answer: 3. Headache, restlessness, and confusion Rationale: When a client is experiencing respiratory acidosis, the respiratory rate and depth increase in an attempt to compensate. The client also experiences headache, restlessness, and mental status changes such as drowsiness and confusion, visual disturbances, diaphoresis, and cyanosis as the hypoxia becomes more acute, hyperkalemia, a rapid irregular pulse, and dysrhythmias.
A client with a history of lung disease is at risk for developing respiratory acidosis. The nurse should assess the client for which signs and symptoms characteristic of this disorder? 1. Bradycardia and hyperactivity 2. Decreased respiratory rate and depth 3. Headache, restlessness, and confusion 4. Bradypnea, dizziness, and paresthesias
Answer: 3. Headache, restlessness, and confusion Rationale: When a client is experiencing respiratory acidosis, the respiratory rate and depth increase in an attempt to compensate. The client also experiences headache; restlessness; mental status changes, such as drowsiness and confusion; visual disturbances; diaphoresis; cyanosis as the hypoxia becomes more acute; hyperkalemia; rapid, irregular pulse; and dysrhythmias. Options 1, 2, and 4 are not specifically associated with this disorder.
The nurse is planning to obtain blood for arterial blood gas (ABG) analysis from a client with chronic obstructive pulmonary disease. The nurse should plan time for which activity after the arterial blood specimen is drawn? 1. Holding a warm compress over the puncture site for 5 minutes 2. Encouraging the client to open and close the hand rapidly for 2 minutes 3. Applying pressure to the puncture site by applying a 2 × 2 gauze for 5 minutes 4. Having the client keep the radial pulse puncture site in a dependent position for 5 minutes
Answer: 3. Applying pressure to the puncture site by applying a 2 × 2 gauze for 5 minutes Rationale: Applying pressure over the puncture site reduces the risk of hematoma formation and damage to the artery. A cold (not warm) compress would aid in limiting blood flow. Keeping the extremity still and out of a dependent position will aid in the formation of a clot at the puncture site.
A client with a 3-day history of nausea and vomiting presents to the emergency department. The client is hypoventilating and has a respiratory rate of 10 breaths/minute. The electrocardiogram (ECG) monitor displays tachycardia, with a heart rate of 120 beats/minute. Arterial blood gases are drawn and the nurse reviews the results, expecting to note which finding? 1. A decreased pH and an increased CO2 2. An increased pH and a decreased CO2 3. A decreased pH and a decreased HCO3 4. An increased pH with an increased HCO3
Answer: 4. An increased pH with an increased HCO3 Rationale: Clients experiencing nausea and vomiting would most likely present with metabolic alkalosis resulting from loss of gastric acid, thus causing the pH and HCO3 to increase. Symptoms experienced by the client would include hypoventilation and tachycardia. Option 1 reflects a respiratory acidotic condition. Option 2 reflects a respiratory alkalotic condition, and option 3 reflects a metabolic acidotic condition.
A client experiencing metabolic acidosis is to be admitted to the nursing unit. The nurse develops a plan of care to support the client physiologically until the tubular cells secrete a sufficient amount of which substance? 1. Phosphates 2. Hydrogen ions 3. Ammonium ions 4. Carbon dioxide molecules
Answer:2. Hydrogen ions Rationale: Hydrogen ions are cations that contribute to a state of acidosis in the body. The renal tubules secrete hydrogen ions and potassium effectively, and in lesser amounts they secrete ammonia and uric acid. Phosphates are anions that tend to neutralize cations. The tubules reabsorb carbon dioxide molecules.
The nurse notes that a client's arterial blood gas results reveal a pH of 7.50 and a Pco2 of 30 mm Hg. The nurse monitors the client for which clinical manifestations associated with these arterial blood gas results? Select all that apply. 1. Nausea 2. Confusion 3. Bradypnea 4. Tachycardia 5. Hyperkalemia 6. Lightheadedness
Answers: 1, 2, 4, 6 Rationale: Respiratory alkalosis is defined as a deficit of carbonic acid or a decrease in hydrogen ion concentration that results from the accumulation of base or from a loss of acid without a comparable loss of base in the body fluids. This occurs in conditions that cause overstimulation of the respiratory system. Clinical manifestations of respiratory alkalosis include lethargy, lightheadedness, confusion, tachycardia, dysrhythmias related to hypokalemia, nausea, vomiting, epigastric pain, and numbness and tingling of the extremities. Hyperventilation (tachypnea) occurs.
What are the possible causes of metabolic acidosis?
Diabetic Ketoacidosis (DKA), decreased carbohydrate intake (starvation ketoacidosis), alcohol abuse (alcoholic ketoacidosis), Lactic acidosis (from tissue anoxia), diarrhea (bicarbonate loss), ingestion of acids or acid precursors such as boric acid, aspirin (acetylsalicylic acid), or methanol or antifreeze (acid precursors), thyroid storm, oliguria from any cause, or draining intestinal or pancreatic fistula (bicarbonate loss)
What are some basic nursing interventions for acid base imbalance?
provide safety and comfort support compensatory mechanisms administer collaborative interventions: treatment of underlying cause adjustment of pH (controversial) monitor for complications of therapy Teach how to avoid in the future (if appropriate) or when to seek help (if chronic)
