Combo with "ABGs & Fluids"
How it happens....
When a patient hypoventilates, carbon dioxide builds up in the bloodstream and pH drops below normal - respiratory acidosis. The kidneys try to compensate for a drop in pH by conserving bicarbonate (base) ions, or generating them in the kidneys, which in turn raises the pH. Respiratory acidosis can result from neuromuscular problems, depression of the respiratory center in the brain, lung diseases, or an airway obstruction.
In a patient with COPD, the primary imbalances is likely to be:
respiratory acidosis.
ECG expose
You may see ECG changes, including a prolonged PR interval, a flattened T wave, a prominent U wave, and a depressed ST segment.
Your bedridden patient has these ABG results: pH, 7.5; Paco2 26, HCO3 24. He's dyspneic and has a swollen right calf. The patient is most likely suffering from:
a pulmonary embolis.
Balance is maintained by ______ _______, respiratory reactions, and kidney reactions.
chemical buffers
kyphoscoliosis
combination of kyphosis and scolisis, which may produce a severe restrictive lung defect as a result of poor lung expansion.
If hydrogen ion concentration ________, pH _______ (alkalosis).
decreases, increases.
Acid-base depends on the regulation of ______ ______ _______.
free hydrogen ions.
Common Lab Values for Electrolytes
http://www.drstandley.com/labvalues_electrolyte.shtml
Normal Lab Values for ABGs
http://www.globalrph.com/abg_analysis.htm
DKA and Kussmaul Breathing
http://www.youtube.com/watch?v=gy7VEVPnOn4 Acidotic breathing in a child - http://www.youtube.com/watch?v=0YJxz-Sxx90
Allen's test
http://www.youtube.com/watch?v=rIW7Lm33yjo
Everything you ever wanted to know about mastering ABGs is in this video. It is 20 minutes long and worth every minute. A MUST SEE!!!
http://www.youtube.com/watch?v=rV2PDQJTKDU
If hydrogen ion concentration ________, pH ________ (acidosis).
increase, decreases
The body compensates for chronic respiratory alkalosis by:
increasing excretion of bicarbonate.
iatrogenic
induced by a physician's words or therapy (used especially of a complication resulting from treatment).
When assessing a patient with DKA, you detect Kussmal's respirations. You realize the body is in:
metabolic acidosis with compensation.
Before and after you administer sodium bincarbonate, you should flush the IV line with:
normal saline solution.
_____ determines the extent of acity or alkalinity, both of which are measured.
pH
What test show....
- ABG analysis is the key test for detecting respiratory acidosis. Typically, pH is below 7.35, and Paco2 is above 45 mm Hg. The bicarbonate level varies, depending on how long the acidosis has been present. In a patient with acute respiratory acidosis, bicarbonate may be normal; in a patient with chronic respiratory acidosis, it may be above 26 mEq/L. - Chest x-rays can help pinpoint some causes, such as COPD, pneumonia, pneumothorax, and pulmonary edema. - Serum electrolyte levels with potassium greater than 5 mEq/L typically indicate hyperkalemia. In acidosis, potassium leaves the cell, so expect serum level to be elevated. - Drug screening may confirm a suspected overdose.
What tests show.....
- ABG may reveal a blood pH >7.45 and a bicarbanate level >26. If the underlying cause is excessive acid loss, the Bicarbonate level may be normal. The Paco2 level may be >45, indicating respiratory compensation. - Serum electrolyte levels usually indicate low potassium, calcium, and chloride levels. Bicarbonate level are elevated. - ECG changes may occur, such as low T wave that merges with the P wave.
Oxygen: Too much of a good thing...
- Administer oxygen as ordered. Generally, patients with COPD should receive lower concentrations of oxygen. The medulla of a patient with COPD is accustomed to high carbon dioxide levels. A lack of oxygen, called the hypoxic drive, stimulates those patients to breathe. Too much oxygen diminishes that drive and depresses respiratory efforts. - Perform tracheal suctioning, incentive spirometry, postual drainage, and coughing and deep breathing exercises as indicated. - Make sure the patient takes in enough fluids, both oral and IV, and maintain accurate intake and output records. - Provide reassurance to the patient and family. - Keep in mind that any sedative you give to the patient can decrease his respiratory rate. - Institute safety measures as needed to protect confused patient.
How you intervene....
- Allay axiety whenever possible to prevent hyperventilation. - Monitor vital signs. - Monitor ABG and serum electrolytes. - If ventilated, check settings frequently. - Provide undisturbed rest periods after patient returns to normal. - Institute safety measures and seizure precautions. - Document all care.
Evaluation...
- Has the patient's LOC returned to normal. - Vital signs stabalized? - Have ABG, blood glucose, serum electrolyte, levels improved? - Is cardiac output normal? - Regained normal sinus rhythm? - Ventilating adequately?
Questions for reevaluating your patient's condition...
- Have the patient's respiratory rate and LOC returned to normal? - Does auscultation of the patient's chest reveal reduced adventious breath sounds? - Have tachycardia and ventricular arrhythmias been stabalized? - Have the patient's cyanosis and dyspnea diminished? - Have the patient's ABG results and serum electrolyte levels returned to normal? - Do chest x-rays show improvement in the condition of the patient's lungs?
How it's treated....
- IV administration of ammonium chloride or arginine monohydrochloride; rarely done but sometimes necessary in severe cases. - Discontinuation of thiazide diuretics and NG suctioning. - Administration of an antimetic to treat underlying nausea and vomiting. - Addition of acetazolamide (Diamox) to inhibit calcium and increase renal excretion of bicarbonate.
How you intervene....
- Monitor vital signs - Assess patients LOC - Administer oxygen as ordered. - Institute seizure precautions. - Administer diluted IV potassium solutions. - Monitor intake and output. - Infuse 0.9% ammonium chloride no faster than 1 L over 4 hours. - Irrigate an NG tube with normal saline instead of tap water. - Assess lab test - Watch closely for S&S of muscle weakness, tetany, or decreased activity.
How you intervene....
- Monitor vital signs and assess cardiac rhythm. - Prepare for mechanical ventilation or dialysis if required. - Closely monitor neurological status. - Insert IV as ordered and have large bore cathether in place for emergencies. - Administer sodium bicarbonate as ordered. - Position patient to promote chest expansion and ease breathing. - Record intake and output.
Patient teaching...
- description of the condition and how to prevent it. - reasons for repeated arterial blood gas analysis. - deep breathing exercises. - prescribed medications. - home oxygen therapy if indicated. - warning signs and symptoms and when to report them. - proper technique for using bronchodilators if appropriate. - need for frequent rest. - need for increased caloric intake if appropriate.
What test show....
- pH is below 7.35, Paco2 may be less than 33 mm Hg, indicating compensatory attempts by the lungs to the body of excess carbon dioxide. - Serum potassium levels are usually elevated as hydrogen ions move into the cells and potassium moves out to maintain electro-neutrality. - Blood glucose and serum ketone levels rise in patients with DKA. - Plasma lactate levels rise in patients with lactic acidosis. - The anion gap is increased. This measurement is calculated by subtracting the amount of negative ions (chloride plus bicarbonate) from the amount of positive ion (sodium). Sometimes the amount of potassium ion is added to the amount of the positive ion, but the amount of potassium ion is usually so small that the calculation doesn't change. The normal anion gap is 8-14 mEq/L. - ECG changes assoicated with hyperkalemia - such as tall T waves, prolonged PR intervals, and wide QRS complexes - may be found.
What test show....
-Typically, pH is above 7.45 and Paco2 is below 35 mm Hg. The bicarbonate level may be normal (22-26 mEq/L) when alkalosis is acute but usually falls below 22 mEq/L when alkalosis is chronic. - Serum electrolyte levels may point to a metabolic disorder that is causing compensatory respiratory alkalosis. Hypokalemia may be evident, signaled by decreased LOC. The ionized serum calcium level may be decreased in those with severe respiratory alkalosis. - ECG findings may indicate arrhythmias or the changes associated with hypokalemia. - Toxicology screening may reveal salicylate poisoning.
You are caring for a patient admitted with diabetes mellitus, malnutrition, and massive GI bleed. In analyzing the morning lab results, the nurse understands that a potassium level of 5.5 mEq/L could be caused by which of the following factors in this patient (select all that apply)? A. The potassium level may be increased if the patient has renal nephropathy. B.The patient may be excreting extra sodium and retaining potassium because of malnutrition. C.The potassium level may be increased as a result of dehydration that accompanies high blood glucose levels. D.There may be excess potassium being released into the blood as a result of massive transfusion of stored hemolyzed blood.
A,C,D. Hyperkalemia may result from hyperglycemia, renal insufficiency, and/or cell death. Diabetes mellitus, along with the stress of hospitalization and illness, can lead to hyperglycemia. Renal insufficiency is a complication of diabetes. Malnutrition does not cause sodium excretion accompanied by potassium retention; thus it is not a contributing factor to this patient’s potassium level. Stored hemolyzed blood can cause hyperkalemia when large amounts are transfused rapidly.
A nurse is assigned to care for a group of clients. On review of the clients' medical records, the nurse determines that which client is at risk for fluid volume deficit? A. A client with a colostomy. B. A client receiving frequent wound irrigation. C. A client with congestive heart failure. D. A client with decreased kidney function.
A. A client with a colostomy. Causes of fluid volume deficit include vomiting, diarrhea, conditions that cause increased respirations or increase urinary output, insufficient IV fluid replacement, draing fistulas, and the presence of an ileostomy or colostomy. A client with CHF or decreased kidney fuction or a client receiving frequent wound irrigation is at risk for fluid volume excess.
A nurse reviews the serum phophorus level and notes that the client's level is 2.0 mg/dL. Which condition most likely caused this serum phosphorus level? A. Alcoholism B. Hyperparathyroidism C. Tumor lysis syndrome D. Renal insufficiency
A. Alcoholism The normal serum phosphorus level is 2.7-4.5 mg/dL. Causative factor relates to malnutrition or starvation and the use of aluminum hydroxide-based or magnesium-based antacids. Malnutrition is associated with alcoholism.
A nurse is assessing a client with a suspected diagnosis of hypocalcemia. Which of the following clinical manifestations are not associated with this diagnosis? A. Hypoactive bowel sounds. B. Parathesias. C. Hyperactive deep tendon reflexes D. Positive Trousseau's sign
A. Hypoactive bowel sounds. This is a sign of hypercalcemia. Signs of hypocalcemia include increased neuromuscular excitability, muscle cramps, twitching, tetany, seizures, irritability, and anxiety. GI symptoms include increased gastric motility, hyperactive bowels sounds, abdominal cramping, and diarrhea.
A nurse is reviewing a client's laboratory reports and notes that the serum calcium level is 4.0 mg/dL. The nurse understands that which condition most likely caused this serum calcium level? A. Prolonged bed rest. B. Excessive administration of vitamin D. C. Renal insufficiency. D. hyperparathyroidism
A. Prolonged bed rest. The normal serum calcium level is 8.6-10.0 mg/dL. A client with a serum calcium level of 4.0 is experiencing hypocalcemia. A and D are associated with hypercalcemia. End-stage renal disease rather than renal insufficiency is a cause of hypocalcemia.
A nurse is caring for a client with diabetic ketoacidosis and documents that the client is experiencing Kussmaul's respirations. Based on this documentation, which of the following did the nurse observe? A. Respirations that are abnormally deep, regular, and increased in rate. B. Respirations that are regular but abnormally slow. C. Respirations that are labored and increased in depth and rate. D. Respirations that cease for several seconds.
A. Respirations that are abnormally deep, regular, and increased in rate. B indicates bradypnes C indicates hyperpnea D indicates apnea
A nurse plans care for a client with COPD, knowing that the client is most likely to experience what type of acid-base imbalance? A. Respiratory acidosis. B. Respiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis
A. Respiratory acidosis. Most often due to hypoventilation.
You are caring for a patient with metastatic bone cancer. Which of the following clinical manifestations would alert you to the possibility of hypercalcemia in this patient? A. Weakness B. Paresthesia C. Facial spasms D. Muscle tremors
A. Signs of hypercalcemia are lethargy, headache, weakness, muscle flaccidity, heart block, anorexia, nausea, and vomiting. Paresthesia, facial spasms, and muscle tremors are symptoms of hypocalcemia.
A nurse caring for a group of clients reviews the electrolyte laboratory results and notes a potassium level of 5.5 mEq/L on one client's laboratory reports. The nurse understands that which client is a most risk for the development of a potassium values at this level? A. The client who has sustained a traumatic burn. B. The client with Cushing's syndrome. C. The client with colitis. D. The client who has been over using laxatives.
A. The client who has sustained a traumatic burn. A serum potassium level greater than 5.1 mEq/L indicates hyperkalemia. Clients who experience cellular shifting of potassium in the early stages of massive cell destruction, such as trauma, burns, or sepsis or with metabolic or respiratory acidosis, are at risk for hyperkalemia.
A nurse is caring for a group of clients reviews the electrolyte laboratory results and notes a sodium level of 130 mEq/L on one client's laboratory reports. The nurse understands that which client is at most risk for the development of a sodium value at the level? A. The client who is taking diuretics. B. The client who is taking corticosteroids. C. The client with renal failure. D. The cleint with hyperaldosteronism.
A. The client who is taking diuretics. Hyponatremia is evidenced by a serum sodium level less than 135 mEq/L.
You are caring for a patient admitted with an exacerbation of asthma. After several treatments, the ABG results are pH 7.40, PaCO2 40 mm Hg, HCO3 24 mEq/L, PaO2 92 mm Hg, O2 saturation 99%. You interpret these results as which of the following? A. Within normal limits B. Slight metabolic acidosis C. Slight respiratory acidosis D. Slight respiratory alkalosis
A. The normal pH is 7.35 to 7.45. Normal PaCO2 levels are 38 to 48 mm Hg and HCO3 is 22 to 26 mEq/L. Normal PaO2 is >80 mm Hg. Normal oxygen saturation is >95%. Since the patient's results all fall within these normal ranges, the nurse can conclude that the patient's blood gas results are within normal limits.
Which of the following serum potassium results best supports the rationale for administering a stat dose of potassium chloride 20 mEq in 250 ml of NSS over 2 hours? A.3.1 mEq/L B.3.9 mEq/L C.4.6 mEq/L D.5.3 mEq/L
A. The normal range for serum potassium is 3.5 to 5.0 mEq/L. This IV order provides a substantial amount of potassium. Thus the patient's potassium level must be low. The lowest value shown is 3.1 mEq/L.
You receive a physician's order to change a patient's IV from D5½ NS with 40 mEq KCl/L to D5NS with 20 mEq KCl/L. Which of the following serum laboratory values, documented on this same patient, best supports the rationale for this IV order change? A. Sodium 136 mEq/L, potassium 4.5 mEq/L B. Sodium 145 mEq/L, potassium 4.8 mEq/L C. Sodium 135 mEq/L, potassium 3.6 mEq/L D. Sodium 144 mEq/L, potassium 3.7 mEq/L
A. The normal range for serum sodium is 135 to 145 mEq/L, whereas the normal range for potassium is 3.5 to 5.0 mEq/L. The change in the IV order decreases the amount of potassium and increases the amount of sodium. Therefore for this order to be appropriate, the potassium level must be near the high end and the sodium level near the low end of their respective ranges.
A nurse prepares to administer potassium chloride intravenously as prescribed to a client with hypokalemia. Which of the following would not be a part of the nurse's plan regarding the preparation and administration of the potassium? A. prepare the medication for bolus administration. B. obtain a controlled IV infusion pump. C. Dilute in appropriate amount of normal saline. D. Monitor urine output during administration.
A. prepare the medication for bolus administration. Potassium chloride is never given by bolus (IV push). Can result in cardiac arrest.
A nurse is preparing to care for a client with a potassium deficit. The nurse reviews the client's record and determines that the client is at risk for developing the potassium deficit because the client.... A. requires nasogastric suctioning. B. has a history of renal disease. C. has hisrory of Addison's disease. D. is taking a potassium-sparing diuretic.
A. requires nasogastric suctioning. A is at risk for hypokalemia. B, C, and D are at risk for hyperkalemia.
_____ analysis is the major diagnostic tool for evaluating acid-base states.
ABG
Hypoxia (pant!)...
Acute hypoxia, secondary to high altitude, pulmonary disease, severe anemia, pulmonary embolus, or hypotension, can cause respiratory alkalosis. Such conditions may overstimulate the respiratory center and cause the patient to breathe faster and deeper. Overventilation during mechanical ventilation causes the lungs to blow off more carbon dioxide, resulting in respiratory alkalosis.
What to look for....
An increase in the rate and depth of respirations is a primary sign of respiratory alkalosis. It's also common for the patient to have tachycardia. The patient may appear anxious and restless as well as complain of lightheadedness, muscle weakness, or difficulty breathing.
How it happens....
Any clinical condition that increases respiratory rate or depth can cause the lungs to eliminate, or "blow off", carbon dioxide.Because carbon dioxide is an acid, eliminating it causes a decrease in Paco2 along with an increase in pH - alkalosis.
So depressing....
As pH drops, the CNS is further depressed, as is myocardial function. Cardiac output and blood pressure drop, and arrhythmias may occur if the patient also has hyperkalemia. Initially, the skin is warm and dry as a result of peripheral vasodilation but, as shock develops, the skin becomes cold and clammy. The patient may complain of weakness and a dull headache as the cerebral vessels dilate. The patient's LOC may deteriorate from confusion to stupor and coma. A neuromuscular examination may show diminished muscle tone and deep tendon reflexes. Metabolic acidosis also affects the GI system, causing anorexia, nausea, and vomitiing.
Poison pills....
At particular risk for metabolic acidosis are patients with poisoning or a toxic reaction to a drug. This can occur following inhalation of toluene or ingestion of a saliclate (such as aspirin or an aspirin-containing medication), methanol, ethylene glycol, paraldehyde, hydrocloric acid, or ammonium cloride.
While performing patient teaching regarding hypercalcemia, which of the following statements are appropriate (select all that apply)? A. Have patient restrict fluid intake to less than 2000 ml/day. B. Renal calculi may occur as a complication of hypercalcemia. C. Weight-bearing exercises can help keep calcium in the bones. D. The patient should increase daily fluid intake to 3000 to 4000 ml. E. Treatment of heartburn can best be managed with Tums on a prn basis.
B,C,D. A daily fluid intake of 3000 to 4000 ml is necessary to enhance calcium excretion and prevent the formation of renal calculi, a potential complication of hypercalcemia. Tums are a calcium-based antacid that should not be used in patients with hypercalcemia. Weight-bearing exercise does enhance bone mineralization.
You are caring for a patient admitted with a diagnosis of COPD who has the following arterial blood gas results: pH 7.33, PaO2 47 mm Hg, PaCO2 60 mm Hg, HCO3 32 mEq/L, and O2 saturation of 92%. Which of the following is the correct interpretation of these results? A. Fully compensated respiratory alkalosis B. Partially compensated respiratory acidosis C. Normal acid-base balance with hypoxemia D. Normal acid-base balance with hypercapnia
B. A low pH (normal 7.35-7.45) indicates acidosis. In the patient with respiratory disease such as COPD, the patient retains carbon dioxide (normal 38-48 mm Hg), which acts as an acid in the body. For this reason, the patient has respiratory acidosis. The elevated HCO3 indicates a partial compensation for the elevated CO2.
You are admitting a patient with complaints of abdominal pain, nausea, and vomiting. A bowel obstruction is suspected. You assess this patient for which of the following anticipated primary acid-base imbalances if the obstruction is high in the intestine? A. Metabolic acidosis B. Metabolic alkalosis C. Respiratory acidosis D. Respiratory alkalosis
B. Because gastric secretions are rich in hydrochloric acid, the patient who is vomiting will lose a significant amount of gastric acid and be at an increased risk for metabolic alkalosis.
You are caring for a patient admitted with heart failure. The morning laboratory results reveal a serum potassium level of 2.9 mEq/L. Which of the following classification of medications should you withhold until consulting with the physician? A. Antibiotics B. Loop diuretics C. Bronchodilators D. Antihypertensives
B. Loop diuretics are contraindicated during episodes of hypokalemia because these medications cause the kidneys to excrete sodium and potassium. Thus administration of this type of medication at this time would worsen the hypokalemia, putting the patient at risk for dysrhythmias. The prescribing physician should be consulted for potassium replacement therapy, and the drug should be withheld until the potassium has returned to normal range.
Which of the following nursing interventions is most appropriate when caring for a patient with dehydration? A. Auscultate lung sounds q2hr. B. Monitor daily weight and intake and output. C. Monitor diastolic blood pressure for increases. D. Encourage the patient to reduce sodium intake.
B. Measuring weight is the most reliable means of detecting changes in fluid balance. Weight loss would indicate the dehydration is worsening, whereas weight gain would indicate restoration of fluid volume. Recall that a 1-kg weight gain indicates a gain of approximately 1000 ml of body water.
A 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 mmHg. The nurse determined that the client is experiencing respiratory alkalosis. Which laboratory value would most likely be noted in this condition? A. Sodium level of 145 mEq/L B. Potassium level of 13.0 mEq/L C. Magnesium level of 2.0 mg/dL D. Phosphorus level of 4.0 mg/dL
B. Potassium level of 13.0 mEq/L Normal potassium values are 3.5-5.5 All other are WNL
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 the ..... A. popliteal circulation B. ulnar circulation C. femoral circulation D. carotid circulation
B. ulnar circulation Allen's test should always be performed before ABG test.
______ (HCO3) level reflects the activity of the kidneys in retaining or excreting bicarbonate.
Bicarbonate
You must prepare the correct IV solution before administration. The order reads for the patient to receive D5½ NS with 40 mEq KCl/L at 125 ml/hr. You must add KCl to the IV because no premixed solutions are available. The unit medication supply has a stock of KCl 3 mEq/ml in multidose vials. Which of the following amounts of KCl should you add to a liter of D5½ NS to obtain the correct solution? A.10 ml B.7.5 ml C.13.3 ml D.15 ml
C. 40 mEq/L (dose desired) ÷ 3 mEq/ml (dose available) = 13.3 ml
When planning care for adult patients, you conclude that which of the following oral intakes is adequate to meet daily fluid needs of a stable patient? A. 500 to 1500 ml B. 1200 to 2200 ml C. 2000 to 3000 ml D. 3000 to 4000 ml
C. Daily fluid intake and output is usually 2000 to 3000 ml. This is sufficient to meet the needs of the body and replace both sensible and insensible fluid losses. These would include urine output and fluids lost through the respiratory system, skin, and GI tract.
You are caring for a patient receiving D5W at a rate of 125 ml/hr. During the 4:00 pm assessment of the patient, you determine that 500 ml is left in the present IV bag. At which of the following times should the nurse anticipate hanging the next bag of D5W? A. 6:00 pm B. 7:00 pm C. 8:00 pm D. 10:00 pm
C. Divide the 500 ml left in the IV bag by the hourly rate of 125 ml to calculate that the present solution will remain infusing for another 4 hours. If you made this notation at 4:00 pm, the bag is due to be changed at 8:00 pm.
A nurse is caring for a client with an ileostomy understands that the client is at most risk for developing which acid-base disorder? A. Respiratory acidosis B. Resipiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis
C. Metabolic acidosis Intestinal secretions are high in bicarbonate and may be lost through enteric drainage tubes or an ileostomy or with diarrhea. These conditions result in metabolic acidosis.
A nurse is caring for a client with renal failure. Blood gas results indicate a pH of 7.30, a PCO2 of 32 mmHg, and a bicarbonate concentrations of 20 mEq/L. The nurse determined that the client is experiencing metabloic acidosis. Which of the following laboratory values would the nurse expect to note? A. Sodium level is 145 mEq/L B. Magnesium level of 2.0 mg/dL C. Potassium level of 5.2 mEq/L D. Phosphorus level of 4.0 mg/dL
C. Potassium level of 5.2 mEq/L Normal potassium level is 3.5-5.0.
A nurse is reviewing laboratory results and notes that a client's serum sodium level is 150 mEq/L. The nurse reports the serum sodium level to the physician, and the physician prescribes dietary instructions based on the sodium level. Which food item does the nurse instruct the client to avoid? A. Low-fat yogurt. B. Cauliflower. C. Processed oat cereals. D. Peas.
C. Processed oat cereals. The normal serum sodium level is 135-145 mEq/L, Processed foods are high in sodium content. A,B and D are good food sources of phosphorus.
The nurse is caring for a client with CHF. On assessment the nurse notes that the client is dyspneic and that rales are audible on ausculation. The nurse suspects fluid volume excess. What additional signs would the nurse expect to note in this client if fluid volume excess is present? A. a decreased CVP - normal 2-6 mm/Hg B. flat neck and hand veins. C. an increase in blood pressure. D. weight loss
C. an increase in blood pressure. Assessment findings associated with fluid volume excess include cough, dyspnea, rales, tachypnea, tachycardia, an elevated blood pressure, a bounding pulse, and elevated DVP, weight gain, edema, nec and hand vein distention, altered LOC, and decreased hematocrit.
A nurse reviews the glood gas results of a client with Guillain-Barre syndrome. The nurse analyzes the results and determines that the client is experiencing respiratory acidosis. Which of the following validates the nurse's findings? A. pH 7.50, PCO2 52 mmHg B pH 7.35, PCO2 44 mmHg C. pH 7.25, PCO2 50 mmHg D. pH 7.50, PCO2 30 mmHg
C. pH 7.25, PCO2 50 mmHg The normal pH is 7.35-7.45. The normal PCO2 is 35-45.
A nurse reviews the ABG results of a client and notes the following: pH 7.45, PCO2 of 30 mmHg, and bicarbonate concentration of 22 mEq/L. The nurse analyzes these results as indicating.... A. metabolic acidosis, compensated. B. metabolic alkalosis, uncompensated. C. respiratory alkalosis, compensated D. respiratory acidosis, uncompensated.
C. respiratory alkalosis, compensated
More metabolic mishaps...
Cushing's disease can lead to metabolic alkalosis by causing retention of sodium and chloride and urinary loss of potassium and hydrogen. Rebound alkalosis following correction of organic acidosis, such as after cardiac arrest and administration of sodium bicarbonate, can also cause metabolic alkalosis. Posthypercapnic alkalosis occurs when chronic carbon dioxide retention is corrected by mechanical ventilation and the kidneys haven't yet corrected the chronically high bicarbonate levels. Metabolic alkalosis can also result from kidney disease, such as renal artery stenosis, or from multiple transfusions. Certain drugs, such as cortocosteroids and antacids that contain sodium bicarbonate, can also lead to metabolic alkalosis.
You are caring for an elderly patient who is receiving IV fluids postoperatively. During the 8:00 am assessment of this patient, you note that the IV solution, which was ordered to infuse at 125 ml/hr, has infused 950 ml since it was hung at 4:00 am. Which of the following is the priority nursing intervention? A. Notify the physician and complete an incident report. B. Slow the rate to keep vein open until next bag is due at noon. C. Obtain a new bag of IV solution to maintain patency of the site. D. Listen to the patient's lung sounds and assess respiratory status.
D. After 4 hours of infusion time, 500 ml of IV solution should have infused, not 950 ml. This patient is at risk for fluid volume excess, and you should assess the patient's respiratory status and lung sounds as the priority action and then notify the physician for further orders.
You are caring for a patient receiving calcium carbonate for the treatment of osteopenia. Which of the following serum laboratory results would you identify as an adverse effect related to this therapy? A. Sodium falling to 138 mEq/L B. Potassium rising to 4.1 mEq/L C. Magnesium rising to 2.9 mg/dl D. Phosphorus falling to 2.1 mg/dl
D. Calcium has an inverse relationship with phosphorus in the body. When phosphorus levels fall, calcium rises, and vice versa. Since hypercalcemia rarely occurs as a result of calcium intake, the patient's phosphorus falling to 2.1 mg/dl (normal 2.4-4.4 mg/dl), may be a result of the phosphate-binding effect of calcium carbonate.
A nurse is caring for a client who has been taking diuretics on a long-term basis. The nurse suspects a fluid volume deficit. Which assessment finding would the nurse note in a client with condition? A. rales B. Increased blood pressure C. Decreased hematocrit D. Decreased central venous pressure
D. Decreased central venous pressure Assessment findings in a client with fluid volume deficit include increased respirations and heart rate, decreased central venous pressure (CVP) (normal 4-11 mm H2O), weight loss, poor skin turgor, dry mucous membranes, decreased urine volume, increased specific gravity of the urine, increased hematocrit, and altered LOC.
A nurse is caring for a client with acute CHF who is receiving high doses of a diuretic. On assessment the nurse notes that the client has flat neck veins, generalized muscle weakness, and diminished deep tendon reflexes. The nurse suspects hyponatremia. What additional signs would the nurse expect to note in this client if hyponatremia were present? A. Dry skin B. Decreased urinary output. C. Increased specific gravity of the urine. D. Hyperactive bowel sounds.
D. Hyperactive bowel sounds.
When planning care for a patient with dehydration related to nausea and vomiting, the nurse would anticipate which of the following fluid shifts to occur because of the fluid volume deficit? A. Fluid movement from the blood vessels into the cells B. Fluid movement from the interstitial spaces into the cells C. Fluid movement from the blood vessels into interstitial spaces D. Fluid movement from the interstitial space into the blood vessels
D. In dehydration, fluid is lost first from the blood vessels. To compensate, fluid moves out of the interstitial spaces into the blood vessels to restore circulating volume in that compartment. As the interstitial spaces then become volume depleted, fluid moves out of the cells into the interstitial spaces.
A nurse understands that the excessive use of oral antacids containing bicarbonate can result in which acid-base disturbance? A. Respiratory acidosis B. Respiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis
D. Metabolic alkalosis Increases in base components occur as a result of oral or parenteral intake of bicarbonates, carbonates, acetates, citrates, or lactates.
A nurse is caring for a client with a NG tube that is attached to low suction. The nurse monitors the client, knowing that the client is at risk for which acid-base disorder? A. Respiratory acidosis B. Respiratory alkalosis C. Metabolic acidosis D. Metabolic alkalosis
D. Metabolic alkalosis Loss of gastric fluid via NG suction or vomiting causes metabolic alkalosis as a result of the loss of hydorchloric acid.
A nurse is caring for a client with a NG tube. NG tube irrigations are prescribed to be performed once every shift. The client's serum electrolyte results indicate a potassium level of 4.5 mEq/L and a sodium level of 132 mEq/L. Based on these laboratory findings, the nurse selects which solution to use for the NG irrigation? A. Tap water. B. Distilled water. C. Sterile water. D. Normal saline.
D. Normal saline. Potassium level 4.5 mEq/L WNL Sodium level 132 mEq/L is low, indicating hyponatremia. In clients with hyponatremia, normal (isotonic) saline should be used rather than water for GI irrigations.
When assessing a patient admitted with nausea and vomiting, which of the following findings supports the nursing diagnosis of deficient fluid volume? A. Polyuria B. Decreased pulse C. Difficulty breathing D. General restlessness
D. Restlessness is an early cerebral sign that dehydration has progressed to the point where an intracellular fluid shift is occurring. If the dehydration is left untreated, cerebral signs could progress to confusion and later coma.
When planning the care of a patient with dehydration, you would instruct the nursing assistive personnel (NAP) to report which of the following? A. 60 ml urine output in 90 minutes B. 1200 ml urine output in 24 hours C. 300 ml urine output per 8-hour shift D. 20 ml urine output for 2 consecutive hours
D. The minimal urine output necessary to maintain kidney function is 30 ml/hr. If the output is less than this for 2 consecutive hours, the nurse should be notified so that additional fluid volume replacement therapy can be instituted.
A nurse instructs a client at risk for hypokalemia about the foods high in potassium that should be included in the daily diet. The nurse determines that the client understands the food sources of potassium if the client states that food itme lowest in potassium is... A. spinach. B. carrots. C. avocado. D. apples
D. apples. Apples = 159 mg Spinach = 470 mg Carrot = 341 mg Avocado = 1097 mg
A nurse is reading a physician's progress notes in the client's record and reads that the physician has document *insensible fluid loss of approximately 800 mL daily". The nurse understands that this type of fluid loss can occur through... A. the gastrointestinal tract. B. unrinary output C. wound drainage D. the skin
D. the skin Sensible losses are those of which the person is aware, such as through wound drainage, GI tract losses, and urination. Insensible losses may occur without the person's awareness. Insensible losses occur daily through the skin and lungs.
Diuretic danger
Diuretic therapy presents another risk of metabolic alkalosis. Thiazide and loop diuretics can lead to a loss of hydrogen, potassium, and chloride ions from the kidneys. Hypokalemia causes the kidneys to excrete hydrogen ions as they try to conserve potassium. Potassium moves out of the cells as hydrogen moves in, resulting in alkalosis With the fluid loss from diuresis, the kidneys attempt to conserve sodium and water. For sodium to be reabsorbed, hydrogen ions must be excreted. In a process known a contraction alkalosis, bicarbonate is reabsorbed and metabolic alkalosis results.
Bump up the bicarbonate...
Expect to administer IV sodium bicarbonate to neutralize blood acidity in patients with bicarbonate loss and a pH lower than 7.1. Fluids are replaced parenterally as required. Dialysis may be initiated in patients with renal failure or a toxic reaction to a drug. Such patients may receive an antibiotic to treat sources of infection or an antidiarrheal to treat diarrhea-induced bicarbonate loss.
Put potassium in its place....
For patients with diabetes, expect to administer rapid-acting insulin to reverse DKA and drive potassium back into the cell. For any patient with metabolic acidosis, monitor serum potassium levels. Even though the patient initially has high serum potassium levels, the levels drop as acidosis is corrected, and the patient may end up with hypokalemia. Any other electrolyte imbalances should be evaluated and corrected.
Keep track of these tracts....
If hypokalemia affects the GI tract, the patient is likely to experience anorexia, nausea, and vomiting. If it affects the GU tract - that is, if the kidneys are affected - polyuria may result. If left untreated, metabolic alkalosis can result in arrythmias and death.
How you intervene....
If your patient develops respiratory acidosis, maintain a patent airway. Help remove any foreign bodies from his airway and establish an artificial airway. Provide adequate humidification to keep the patient's secretions moist. Also, follow these measures: - Monitor vital signs, and assess cardiac rhythm. Respiratory acidosis can cause tachycardia, alterations in respiratory rate and rhythm, hypotension, and arrhythmias. - Continue to assess respiratory patterns, and report changes quickly. Prepare for mechanical ventilation if indicated. - Monitor the patient's neurologic status, and report sifnifican changes. Also monitor cardiac function because respiratory acidosis may progress to shock and cardiac arrest. - Give medications, such as anitibiotic or a bronchodilator, as prescribed.
That breathless feeling.....
In certain neuromuscular diseases - such as Guillain-Barre syndrome, myathenia gravis, and poliomyelitis - the respiratory muscles fail to respond properly to the respiratory drive, resulting in respiratory acidosis. Diaphragmatic paralysis, which commonly occurs with spinal cord injurty, works the same way to cause respiratory acidosis. Hypo ventilation for CNS trauma or brain lesions - such as tumors, vascular disorders, or infections - may impair the patient's ventilatory drive. Obesity (as in pickwickian syndrome) or primary hypoventilation (as in Ondine's curse) may contribute to this imbalance as well. Also, certain drugs - including anesthetics, hypnotics, opioids, and sedation drugs - can depress the respiratory center of the brain, leading to hypercapnia (excessive level of carbon dioxide in the blood).
In extremis....
In extreme alkalosis, confusion or syncope may occur. Because of the lack of carbon dioxide in the blood and its effect on cerebral blood flow and the respiratory center, you may see alternating periods of apnea and hyperventilation. The patient may complain of tingling in the fingers and toes.
What is Metabolic Alkalosis?
In metabolic alkalosis, the underlying mechanisms include a loss of hydorgen ions (acid), gain in bicarbonate, or both. A Paco2 level greater than 45 mm Hg (possible as high as 60 mm Hg) indicates that the lungs are compensating for alkalosis. Renal compensation is more effective, but slower. Metabolic alkalosis is commonly associated with hypokalemia, particularly from the use of thiazides, furosemide, ethacrynic acid, and other diuretics that deplete potassium stores. In hypokalemia, the kidneys conserve potassium. At the same time, the kidneys also increase the excretion of hydrogen ions, which prompts alkalosis from the loss of acid. Metabolic alkalosis may also occur with hypochloremia and hypocalcemia.
If your patient's NG tube is attached to suction, you know the patient may develop metabolic alkalosis. You expect that his ABG results will show:
Increase pH, increased Paco2, and increased bicarbonate (HCO3).
You're taking care of a patient with obesity-hypoventilation syndrome. You expect to see signs of chronic respiratory acidosis in the patient's ABG results. What do you look for?
Increased bicarbonate (HCO3).
Infants and acidosis...
Infants commonly have problems with acid-base imbalances, particularly acidosis. Because of low residual lung volume, any alteration in respiration can rapidly and dramatically change partial pressure of arterial carbon dioxide leading to acidosis. Infants also have high metabolic rate which yields large amounts of metabolic wastes and acids that must be excreted by the kidneys. Along with their immature buffer system, these age-related differences leave infants prone to acidosis.
What to look for...
Initially, your patient may have slow, shallow respirations as hypoventilation, a compensatory mechanism, occurs. However, this mechanism is limited because hypoxemia soon develops, which stimulates ventilation. The signs and symptoms of metabolic alkalosis are commonly associated with an underlying condition. Characteristic hypokalemia or hypocalcemia ECG changes may occur, as well as signs of hypotention.
If administering dopamine to a patient with hypotension proves ineffective, how should you proceed?
Investigate the patient's pH.
Scanty surface.....
Lung diseases that decrease the amount of pulmonary surface area available for gas exchange can prompt respiratory acidosis. Examples of pulmonary problems that can decrease surface area include respiratory infections, COPD, acute asthma attacks, chronic bronchitis, late stages of adult respiratory distress syndrome, pulmonary edema, conditions in which there's increased dead space in the lungs (hypoventilation) and physiologic or anotomic shunts. Chest wall trauma (leading to pneumothorax or flail chest) can also cause respiratory acidosis. The ventilatory drive remian intact but the chest wall mechanics of the collapsed lung don't allow for sufficient alveolar ventilation to meet the body's needs. Chest wall mechanics can also be impeded as a result of the rib cage distortion caused by fibrothorax or kyphoscoliosis
Ms. Straus is a 24 yr old college student. She has a history of Crohn's disease and is complaining of a 4 day history of bloody-watery diarrhea. A blood gas is obtained to assess her acid/base balance: pH: 7.28 CO2: 43 PO2: 88 HCO3: 20 SaO2: 96% What is your interpretation? What interventions would be appropriate for Ms Strauss?
Metabolic Acidosis (uncompensated). Intervention - control diarrhea and bowel rest.
Mr. Casper is a 55 yr old with GERD. He takes about 15 Tums antacid tablets a day. An ABG is obtain to assess his acid/base balance: pH: 7.46 CO2: 42 PO2: 86 HCO3: 29 SaO2: 97% What is your interpretation? What interventions would be appropriate for Mr. Casper?
Metabolic Alkalosis (partially compensated) Intervention: Better control of GERD with H2-blockers (Pepcid) or PPIs (Prilosec).
Gut reactions....
Metabolic acidosis also occurs with excessive GI losses from diarrhea, intestinal malabsorption, a draining fistula of the pancreas or liver, or a urinary diversion to the ileum. Other causes include hyperaldosteronism and use of a potassium-sparing diuretic such as acetaxolamide, which inhibits the secretion of acid.
Kidney culprit....
Metabolic acidosis can also stem from a decreased ability of the kidneys to excrete acids, as occurs in renal insufficiency or renal failure with acute tubular necrosis.
What is metabolic acidosis?
Metabolic acidosis is caused by an increase in hydrogen ion production and is characterized by a pH below 7.35 and a bicarbonate level below 22 mEq/L. This disorder depresses the CNS. Left untreated, it may lead to ventricular arrythmias, coma, and cardiac arrest.
Acids ante up, bases bottom out....
Metabolic acidosis is characterized by a gain in acids, or a loss of bases from the plasma. The condition may be related to an overproduction of ketone bodies. This occurs when the body has used up its glucose supplies and draws from fate stores for energy, converting fatty acids to ketone bodies. Conditions that cause an overproduction of ketone bodies include diabetes mellitus, chronic alcoholism, severe malnutrition or starvation, poor dietary intake of carbohydrates, hyperthyroidism, and severe infection with accompany fever. Lactic acidosis can cause or worsen metabolic acidosis and can occur secondary to shock, heart failure, pulmonary disease, hepatic disorders, seizures, or strenuous exercise.
What to look for....
Metabolic acidosis typicall produces respiratory neurologic, and cardiac signs and symptoms. As acid builds up in the bloodstream, the lungs compensate by blowing off carbon dioxide. Hyperventilation, especially increased depth of respirations, is the first clue to metabolic acidosis. Called Kussmaul's respirations, the breathing is rapid and deep. A patient with diabetes who experiences Kussmaul's respiration may have a fruity breath odor. The odor stems from catabolism of fats and excretion of acetone.
GI Grief...
Metabolic alkalosis can result from many causes, the common of which is excessive acid loss from the GI tract. Vomiting causes loss of hydrocloric acid from the stomach. Children who have pyloric stenosis can develop this disorder. Alkalosis also results from prolonged nasogastric (NG) suctioning, presenting a risk for surgical patients and patients with GI disorder.
A neurologic nightmare...
Metabolic alkalosis results in neuromuscular exctability, which causes muscles twitching, weakness, and tetany. The patient develops hyperactive reflexes. He may also experience numbness and tingling of the fingers, toes, and mouth area. Neurologic symptoms include apathy and confusion. Seizures, stupor, and coma may result.
After resuscitating Mrs Dobins, you find Mr. Simmons to be in respiratory distress. he has a history of Type-I diabetes mellitus and is now febrile. (Wow, what a bad day). His ABG shows: pH: 7.00 CO2: 59 PO2: 86 HCO3: 14 SaO2: 91% What is your interpretation? What interventions would be appropriate for Mr Simmons?
Metabolic and Respiratory Acidosis with Hypoxemia. Intervention: Increase oxygen, treat pneumonia with antibiotics, and administer IV insulin and fluids to treat DKA.
Mrs Dobins is found pulseless and not breathing this morning. After a couple minutes of CPR she responds with a pulse and starts breathing on her own. A blood gas is obtained: pH: 6.89 CO2: 70 PO2: 42 HCO3: 13 SaO2: 50% What is your interpretation? What interventions would be appropriate for Mrs. Dobins?
Metabolic and Respiratory Acidosis with Hypoxemia. Intervention: Intubation, mechanical ventilation, blood pressure and circulatory support.
Mr Karl is a 80 yr old nursing home resident admitted with urosepsis. Over the last two hours he has developed SOB and is becoming confused. His ABG show the following results: pH: 7.02 CO2: 55 PO2: 77 HCO3: 14 SaO2: 89% What is your interpretation? What interventions would be appropriate for Mr Karl?
Metabolic and Respiratory Acidosis with Hypoxemia. Intervention: Mechanical Ventilation. If hypotension exist, aggressive fluid and vasopressor support.
A breakdown in breathing....
Most patients with respiratory acidosis have rapid, shallow respirations; they my be dyspneic and diaphoretic. Auscultation reveals dimished or absent breath sounds over the affected area. However, if acidosis stems from CNS trauma or lesions or drug overdose, the respiratory rate is greatly decreased. In a patient with acidosis, hyperkalemia, and hypoxemia, you may note tachycardia and ventricular arrthymias. Cyanosis is a late sign of the condition. Resulting myocardial depression may lead to shock and, ultimately, cardiac arrest.
_____ reflects the adequacy of ventilation by the lungs.
Paco2
fibrothorax
Pleural thickening extending over more than one fourth of the costal pleural surface. Commonly results from resolution of an exudative pleural effusion (including asbestos-related effusions), Empyema, or Hemothorax. Pleurectomy (decortication) may be necessary to restore function.
Mrs. Lauder is a thin, elderly-looking 61 yr old COPD patient. She has an ABG done as part of her routine care in the pulmonary clinic. The results are as follows: pH: 7.37 CO2: 63 PO2: 58 HCO3: 35 SaO2: 89% What is your interpretation? What interventions would be appropriate for Mrs. Lauder?
Respiratory Acidosis (fully compensated) Intervention: This is Mrs Lauder's baseline. No treatment required.
Mr Frank is a 60 yr old with pneumonia. He is admitted with dyspnea, fever, and chills. His blood gas is below: pH: 7.28 CO2: 56 PO2: 70 HCO3: 25 SaO2: 89% What is your interpretation? What interventions would be appropriate for Mr. Frank?
Respiratory Acidosis (uncompensated). Intervention - Increased ventilation and oxygenation.
Mr. Longo is a 18 yr old comatose, quadriplegic patient who has the following ABG done as part of a medical workup: pH: 7.48 CO2: 22 PO2: 96 HCO3: 16 SaO2: 98% What is your interpretation? What interventions would be appropriate for Mr. Longo?
Respiratory Alkalosis (compensated) Intervention: Chronic hyperventilation syndrome. A chronic and stable condition for him. No treatment necessary.
Ms Berth was admitted for a drug overdose. She is being mechanically ventilated and a blood gas is obtained to assess her for weaning. The results are as follows: pH: 7.54 CO2: 19 PO2: 100 HCO3: 16 SaO2: 98% What is your interpretation? What interventions would be appropriate for Ms Berth?
Respiratory Alkalosis (partially compensated) Intervention: Decrease ventilatory support. Attempts to allow her CO2 to increase back to normal should be made before weaning.
Ms Steele is a 17 yr old with intractable vomiting. She has some electrolyte abnormalities, so a blood gas is obtained to assess her acid/base balance. pH: 7.50 CO2: 36 PO2: 92 HCO3: 27 SaO2: 97% What is your interpretation? What interventions would be appropriate for Ms Steele?
Respiratory Alkalosis (uncompensated) Intervention: Fluids, anti-emetics, management of electrolyte disorders.
Danger! Obstruction ahead....
Respiratory acidosis can also be caused by airway obstruction, which leads to carbon dioxide retention in the lungs. Aiway obstruction can occur as a result of retained secretions, tumors, anaphylaxis, laryngeal spasm, or lung diseases that interfere with alveolar ventilation. Keep in mind that children are particularly prone to airway obstruction, as are elderly and debilitated patients, who may not be able to effectively clear secretions.
What to look for....
S&S of respiratory acidosis depend on the cause of the condition. The patient may complain of a headache because carbon dioxide dilates cerebral blood vessels. CNS depression may result in an altered LOC, ranging from restlessness, confusion, and apprehension to somnolence and coma. If acidosis remains untreated, a fine flapping tremor and depressed reflexes may develop. The patient may also report nausea and vomiting, and the skin may be warm and flushed.
Signs of trouble....
S&S worsen as calcium level drop because of vasoconstriction of peripheral and cerabral vessels resulting from hypoxia. You may see hyperreflexia, carpopedal spasm, tetany, arrrhythmias; a progressively decrease in the patient's LOC, seizures, or coma.
Hyperventilation (gasp!)...
The most common cause of acute respiratory alkalosis is hyperventilation stemming from anxiety or panic attack. it may also occur during cardiopulmonary resuscitation when rescuers hyperventilate the patient at 30 to 40 breathes per minute. Pain can have the same effect. Hyperventilation is also an early sign of salicylate intoxication and can occur with the use of nictine, xanthines such as aminophylline, and other drugs. Hypermetabolic states - such as fever, liver failure, and sepsis (especially gram-negative sepsis) - can lead to respiratory alkalosis. Conditions that affect the respiratory control center in the medulla are also a danger. For example, the higher progesterone levels during pregnancy may stimulate this center, while stroke or trauma may injure it, both resulting in respiratory alkalosis.
What is respiratory alkalosis?
The opposite of respiratory acidosis, respiratory alkalosis results from alveolar hyperventilation and hypocapnia. In respiratory alkalosis, increased elimination of carbon dixide occurs; therefore, pH is greater that 7.45 and Paco2 is less than 35 mm Hg. Acute respiratory alkalosis results from a sudden increase in ventilation. Chronic respiratory alkalosis may be difficult to identify because of renal compensation.
How it happens....
The underlying mechanisms in metabolic acidosis are a loss of bicarbonate from ECF, and accumulation of metabolic acids, or a combination of the two. If the patient's anion gap (measurement of the difference between the amount of sodium and the amount of bicarbonate in the blood) is greater than 14 mEq/L, then the acidosis is a result of an accumulation of metabolic acids (unmeasured anions). If metabolic acidosis is associated with a normal anion gap (8-14 mEq/L), loss of bicarbonate may be the cause.
What is Respiratory Acidosis?
This acid-base disturbance is characterized by alveolar hypoventilation, meaning the pulmonary systems is unable to rid the body of enough carbon dioxide to maintain a healthy pH balance. This occurs because of decreased respiration or inadequate gas exchange. The lack of efficient carbon dioxide release leads to hypercapnia, in which Paco2 is greater than 45 mm Hg. The condition can be acute, resulting from sudden failure in ventilation, or chronic, resulting from chronic pulmonary disease. In acute repiratory acidosis, pH drops below normal (lower than 7.35). In chronic respiratory acidosis, commonly due to COPD, pH stays within normal limits (7.35 - 7.45) because the kidneys have had time to compensate for the imbalance.
It's in the bag....
To counteract hyperventilation, the patient can breathe into a paper bag or into cupped hands. This forces him to breathe exhaled carbon dioxide, thereby raising the carbon dioxide level. If a patient's respiratory alkalosis is iatrogenic, mechanical ventilator settings may be adjusted by decreasing the tidal volume.
How it's treated....
Treatment aims to correct the acidosis as quickly as possible by addressing both the symptoms and the underlying cause. Respiratory compensation is usually the first line of therapy, including mechanical ventilation if needed.
How it's treated....
Treatment focuses on correcting the underlying disorder, which may require removing the causative agent, such as a salicylate or other drug, or taking steps to reduce fever and eliminate the source of sepsis. If acute hypoxemia is the cause, the patient will need oxygen therapy. If anxiety is the cause, the patient amy receive a sedative or an anxiolytic.
How it's treated....
Treatment of respiratory acidosis focuses on improving ventilation and lowering Paco2. If respiratory acidosis stems from non-pulmonary conditions, such as newromuscular disorders or a drug overdose, treatment aims to correct or improve the underlying cause. Treatment includes: - a bronchodilator to open constricted airways. - supplemental oxygen as needed. - drug therapy to treat hyperkalemia. - antibiotic therapy to treat infection. - chest physiotherapy to remove secretions from the lungs. - removal of a foreign body from the patent's airway if needed.
Risky business...
Treatments can also induce respiratory acidosis. For instance, mechanical ventilation that underventilates a patient can cause carbon dioxide retention. A postoperative patient is at risk for respiratory acidosis if fear of pain prevent him from participating in pulmonary hygiene measures, such as coughing and deep breathing. Also analgesics or sedative can depress the medulla (which controls respirations) leading to inadequate ventilation and subsequent respiratory acidosis.
ABG results in respiratory acidosis.
Uncompensated - pH <7.35 - Paco2 (mm Hg) >45 - Bicarbonate (mEq/L) Normal Compensated - pH Normal - Paco2 (mm Hg) >45 - Bicarbonate (mEq/L) >26
ABG results in metabolic acidosis
Uncompensated pH <7.35 Paco2 (mm Hg) Normal Bicarbonate (mEq/L) <22 Compensated pH Normal Paco2 (mm Hg) <35 Bicarbonate (mEq/L) <22
ABG results in metabolic alkalosis
Uncompensated pH > 7.45 Paco2 (mm Hg) Normal Bicarbonate (mEq/L) >26 or normal Compensated pH Normal Paco2 (mm Hg) >45 Bicarbonate (mEq/L) >26 or normal
ABG results in respiratory alkalosis
Uncompensated pH >7.45 Paco2 (mm Hg) <35 Bicarbonate (mEq/L) Normal Compensated pH Normal Paco2 <35 Bicarbonate (mEq/L) <22
Always on alert...
Watch for signs of worsening CNS status or deteriorating laboratory and ABG test results.