A 16-year-old female patient is scheduled for an elective tonsillectomy. The RN is reviews the laboratory results. Which value is most important to report to the surgeon?
The white blood cell count is elevated indicating possible infection. Infection is a relative contraindication for surgery. This is not however a hard and fast rule. Emergent surgery would not be delayed. Surgery to correct the cause of the infection would also not be delayed. In this case the surgery is elective and there is no reason not to delay it. The Platelet count is normal. The chloride is slightly below normal (95-105 mEq/L) but not reason to stop the procedure. The blood glucose is also slightly low but this is expected since the patient was likely NPO for the procedure.
The nurse is reviewing morning lab results on 4 patients. Which patient should be assessed first and then reported to the doctor.
All of these lab values are out of range, the key here is to identify which client needs attention first. First determine if any of the values are critically high or low. “B” can be thrown out because a PTT of 60 sec is high in a ‘normal’ person but expected in a patient on heparin therapy. In “A” the Dilantin level is slightly below therapeutic (should be 10-20) and this patient will probably need their dose increased. In “D” the lithium level is slightly above therapeutic range (0.5 to 1.5) and this patient should be assessed for signs and symptoms of lithium overdose. In “C” the potassium is low but not critical, however; a low potassium in a patient on Digoxin is very dangerous because low potassium potentiates, or increases, the risk of digitalis toxicity. This client should be assessed first and reported to the MD: a potassium supplement, a serum digoxin level and EKG will probably be ordered. Then the other two clients should be assessed.
The nurse is reviewing lab results from a patient who reported abdominal trauma and suspects liver damage. Which lab values should she review to confirm this?
AST and ALT are two of the most important tests to detect liver injury. BUN and Creatinine indicate kidney function. PTT, PT and INR are part of coagulation profile to test bleeding disorders or monitor anticoagulant therapy. An elevated PT/INR is sometimes associated with liver disease however it is much less specific to the liver than AST and ALT. The pH and HCO3 are associated with arterial blood gas. Normal AST and ALT values are 8-40 (References differ greatly on the normal values for these so for the NCLEX just remember anything above 40 is abnormal).
The nurse is caring for a client with end-stage renal failure admitted with serum potassium level of 6.5 mEq/L. The nurse should take the following action first:
A potassium level of 6.5 is CRITICAL. All of these actions should eventually be performed however the priority is to contact the physician and obtain orders to reduce the potassium level. Normal potassium level is 3.5-5.0. The heart is very sensitive to small changes in potassium so an increase or decrease of just 1.0 is critical.
A patient is to be discharged with a new prescription for sodium warfarin (Coumadin®). Which statement by the patient indicates a correct understanding of the laboratory testing necessary for this new medication.
A. B. C. E. D. The therapeutic window on coumadin is very small and it interacts with many medications and certain foods—this means it needs to be monitored closely to ensure that the proper amount is in the bloodstream. The PT (prothrombin time) and INR (international normalized ratio) are used to monitor the effectiveness of warfarin therapy. PTT or aPTT is assessed on a patient taking heparin. Platelet counts are important to assess in patients taking any anticoagulant but it is not necessary to regularly check on patients taking coumadin at home. There is no such lab test that assesses warfarin level and even if there were it would still be more important to assess PT/INR since that expresses the effect of the coumadin on bleeding. A normal PT in a patient not taking coumadin is 9-12 seconds. The therapeutic PT for a patient on coumadin is 1.5 to 2.5 times that number so 14-30 seconds. Unfortunately PT varies greatly between different laboratories. The INR was created to simplify this. The target INR is 2-3 or in some patients up to 4.5 (such as those with a mechanical heart valve). Prioritize remembering that PT and INR is assessed on patients taking Coumadin and memorize the INR numbers: TOO LOW and HIGH FIVE. Less than 2 is too low, greater than 5 is WAY TOO HIGH!
The nurse is reviewing morning lab results and notices that the Digoxin ® level is reported as 2.8 ng/mL and Potassium is 3.9 mEq/L. The following action should be taken:
The therapeutic level for digoxin range from 0.5 to 2.0 ng/mL. A value of 2.8 ng/mL indicates a toxic level has accumulated in the bloodstream. The most appropriate action would be to hold the medication and contact the physician. An EKG would likely be ordered and if the patient is exhibiting signs and symptoms of digoxin toxicity then an antidote will be administered. It would be inappropriate to administer half the normal dose because that requires a new physician order.
A 68-year-old male is admitted late at night to the telemetry floor with a potassium level of 2.6 mEq and sodium level of 115 mEq/L. The client becomes increasingly combative as the nurse prepares IV fluids to correct the electrolyte imbalance. The family of the patient is concerned about the client’s behavior stating that this is not normal for him. What is the most appropriate response by the nurse?
Both the sodium and potassium levels are critically low. Normal sodium is 135-145 and normal potassium is 3.5-5.0. Sodium levels below 120 are associated with confusion, aggressiveness and other neurological deficits. Low potassium causes cardiac abnormalities. “B” is incorrect because dementia is a chronic and irreversible disorder, this client is suffering from delirium which is an acute state of confusion.
The nurse is reviewing the lab results of a client on a heparin drip: PTT = 90 seconds PT = 14 seconds INR = 1.8 Platelets = 12,000/mm3 What action should the nurse take first?
Heparin-induced thrombocytopenia (HIT) is a severe reaction to heparin therapy. A steep drop in platelet count is a hallmark of HIT. The first action would be to stop the infusion. For the NCLEX you generally want to assess the patient before taking action. In this case “C” is not correct because you are already aware that the platelet count is critically low (Normal is 100,000 to 400,000/mm3). You have assessed the lab values and that alone is cause to stop the heparin drip immediately even if the patient does not exhibit any other signs or symptoms of HIT. Also note that “D” would be incorrect because PT is assessed with coumadin therapy, PTT is checked with heparin therapy.
The nurse is assessing a patient admitted the prior night to the maternity floor with preeclampsia and notices diminished deep tendon reflexes. Which lab value would be associated with this?
Hypermagnesemia is associated with diminished deep tendon reflexes. Magnesium supplementation is a common treatment for pregnant women diagnosed with preeclampsia. This patient probably received IV magnesium sulphate overnight and now has a toxic concentration in the bloodstream as evidenced by the diminished reflexes. The other three choices are likely to result in muscular spasms or cramping.
The nurse is reviewing the results of a CBC on a 56-year-old male client who is reporting dizziness and increased fatigue. WBC = 5.9 k/mm3 RBC = 3.2 k/mm3 Hgb = 7.6 g/dL Hct = 22% Platelets = 150 k/mm3 After calling the physician, which order would the nurse expect to receive?
The hemoglobin (Hgb), hematocrit (Hct) and RBCs are all very low. These values indicate anemia and the patient is symptomatic. In general hemoglobin drives the decision to administer blood products and a hemoglobin less than 8 in a symptomatic patient calls for a blood transfusion. Administering plasma or albumin would likely worsen the anemia by further diluting the blood. The platelets are within normal limits.
The nurse educator is providing discharge teaching to a patient with newly diagnosed diabetes mellitus, type II. The client will leave with a prescription for insulin. Which statement by the patient indicates a need for further education?
Glycosylated hemoglobin (Hgb A1c) is a test that shows what blood glucose levels were on average over the past 3 months. In a healthy non-diabetic patient this number should be between 4-6%. The goal for an adult with diabetes is less than 8%. An Hgb A1c of 12% indicates that the patient’s average blood glucose level was around 300 the past 3 months, this suggest poor control of blood sugar levels.
The nurse notices the following trend on a 45-year-old male client’s laboratory workup: Day 1: BUN=10, Cre=0.9 Day 2: BUN=12, Cre=1.2 Day 3: BUN=15, Cre=1.9 The nurse correctly identifies this as a direct consequence of impaired functioning of which body system?
Elevated BUN and Creatinine (Cre) are associated with impaired renal function. The kidneys are part of the urinary system. Impaired cardiac functioning could reduce perfusion to the kidneys resulting in impaired renal function. The best choice is “A” since BUN and Cre are directly associated with renal function.
The nurse is reviewing the results of an arterial blood gas (ABG) on an 88year-old female client. The nurse correctly interprets the results as what disorder? pH = 7.51 PaO2 = 92 SaO2 = 98% PaCO2 = 40 HCO3 = 29 You interpret these results as:
The correct answer is metabolic acidosis because the pH is high and the bicarbonate is high. With ABG questions the first value you look at is the pH to determine acidosis or alkalosis. The pH should be between 7.35 and 7.45. Since the pH is above 7.45 you know the patient is alkalotic and can eliminate the two acidotic choices. Next determine what is causing the alkalosis. Bicarbonate is alkaline so elevated bicarb is causing the alkalosis. HCO3 is a function of metabolism so the cause of the alkalosis is metabolic.
A 14-year-old female patient is brought to the emergency department by ambulance following a motor vehicle accident. The patient complains of pain to the upper left abdomen and lightheadedness. The lab work resulted as follows: WBC=22k/mm3, RBC=2.2 M/ mm3, Hct=27%, Hgb=7.2 g/dL. AST=16 and ALT=22. BUN=22 and Creatinine=1.2. The nurse correctly identifies that the following organ has been injured:
The spleen is the most common organ to be injured following abdominal trauma. Pain is often felt in the upper left abdomen under the ribcage. The spleen holds white blood cells (WBCs) and when injured, the WBC count will increase. The patient is exhibiting signs of anemia (low RBC, low Hgb and low Hct) and lightheadedness, this is also consistent with acute blood loss from a ruptured spleen. The AST and ALT are markers for liver function, anything below 40 is generally accepted as normal. BUN and Cre are markers for renal function but these values are also normal.
The nurse receives report on a client admitted to the psychiatric ward. She is told the client has been nauseas all day and reported feeling too weak and disoriented to go to group therapy. Upon entering the client’s room the nurse finds the client actively seizing. Which laboratory finding would be associated with these signs and symptoms?
Therapeutic lithium levels are 0.8-1.5 mEq/L, a value of 3 would be toxic. Signs and symptoms of lithium toxicity include diarrhea, dizziness, nausea, vomiting, weakness; tremors, disorientation, twitching, slurred speech, disorientation, uncoordinated movements (ataxia); finally seizures and coma. Dilantin is also critically high (normal is 10-20 mcg/dL) but unlikely to elicit these symptoms.
Your patient has been diagnosed with diabetes insipidus. Which laboratory result supports this diagnosis?
Urine specific gravity of 1.005 or less is hallmark of diabetes insipidus. However other conditions such as primary polydipsia and pyelonephritis as well as recent diuretic use could also result in low urine specific gravity. Urine osmolality would be less than 300 and Serum sodium would be expected to be high not low in a patient with diabetes insipidus.
The nurse is caring for a client with a calcium level of 12.6 mg/dL. Which laboratory finding would also be expected in this client?
Calcium and phosphorus levels have an inverse relationship in the body. They are like two partners on a see-saw: as one goes up the other down. If the patient has a high calcium level you would expect phosphorus to be low
A patient is admitted to the telemetry unit with coronary artery disease. Which statement by the patient indicates a correct understanding of lipid blood testing?
High-density lipoproteins (HDL) is also known as “good cholesterol” because it removes cholesterol from the arteries. It is the only one you want to increase. The goal would be to decrease triglycerides, low-density lipoproteins and total cholesterol. Triglycerides should be less than 150. Total cholesterol should be less than 200
Your patient is admitted to the respiratory unit. An arterial blood gas (ABG) is drawn and reveals the following findings: pH = 7.30 PaO2 = 88 SaO2 = 92% PaCO2 = 52 HCO3 = 26 You interpret these results as:
The correct answer is respiratory acidosis because the pH is low, carbon dioxide is high and the bicarbonate is normal. With ABG questions the first value you look at is the pH to determine acidosis or alkalosis. The pH should be between 7.35 and 7.45. Since the pH is below 7.35 you know the patient is acidotic and can eliminate the other two answer choices. Next determine what is causing the acidosis. Carbon dioxide becomes an acid when dissolved in blood so if the PaCO2 is high that means the high CO2 is causing the acidosis. The lungs control CO2 retention so the cause of the acidosis is respiratory.
A client is diagnosed with malnutrition secondary to chemotherapy treatment. Which laboratory finding supports the diagnosis? Select all that apply.
Please select 3 correct answers
Albumin, transferrin and total protein are the lab values most often used to diagnose malnutrition. Serum transferrin is the most sensitive indicator and will decrease first. Malnutrition is also associated with decreased cholesterol, electrolytes and BUN.
The nurse is caring for a patient recently diagnosed with Hepatitis A. The chart shows a serum bilirubin of 4.2 mg/dL. The nurse would expect to find all of the following except:
This patient has hyperbilirubinemia (normal bilirubin is less than 1.0) secondary to the hepatitis. Signs of elevated serum bilirubin are Jaundice (yellow pigmented skin and eyes) and orange urine. Dark tarry stools are associated with upper GI bleed.
The nurse is reviewing lab results on a 45-year-old male admitted to the medical surgical floor with history of congestive heart failure, COPD, HIV and diabetes mellitus, type II. RBC = 5.2 M/mm3 WBC = 500 /mm3 Hgb = 12 g/dL Hct = 38% Platelets = 180,000/mm3 Which precautions does the nurse initiate? Select all that apply.
Please select 2 correct answers
The WBC count is critically low and this patient is at a very high risk for contracting infection. For this reason neutropenic precautions should be initiated. A history of HIV should clue you in to look at WBC or T-Cell CD4 counts. Universal precautions should be applied to all patients. There is no “extra” precautions for patients with HIV or AIDS.
Which of the following clients should the nurse assess first?
3% hypertonic saline is a high-risk medication that requires close monitoring. Treatment often leads to significant over-correction. Normal sodium is 135145. Although a serum sodium of 148 is only slightly above normal, the fact that the patient is on 3% hypertonic saline indicates over-correction and the fluid should be turned off and the physician contacted. Serum sodium should never be allowed to change by more than 8—10 mEq/L every 24 hours.
The client is admitted to the ICU with an admission diagnosis of acute respiratory distress with a history of CHF, severe COPD, GERD and Chronic kidney disease, stage III. An arterial blood gas (ABG) is drawn as part of routine pulmonary function testing and reveals the following findings: pH = 7.29 PaO2 = 60 SaO2 = 80% PaCO2 = 82 HCO3 = 36 You interpret these results as:
This patient has had severe COPD for a while and is retaining CO2. The kidneys have tried to compensate for that by increasing HCO3. Now the patient decompensated and that is why they are being admitted. The correct answer is partially compensated respiratory acidosis because the pH is low, carbon dioxide is high and the bicarbonate is also high. With ABG questions the first value you look at is the pH to determine acidosis or alkalosis. Since the pH is below 7.35 you know the patient is acidotic and can eliminate the other two answer choices. Next determine what is causing the acidosis. Remember “ROME— Respiratory Opposite, Metabolic Equal.” If the pH goes in the opposite direction of PaCO2 and/or HCO3 then it is respiratory. If pH goes in same direction as PaCO2 and/or HCO3 it is metabolic. Here the pH is LOW and PaCO2 and HCO3 are HIGH so it must be Respiratory acidosis. The HCO3 is high because it is trying to compensate for the high CO2.
A client is admitted with a diagnosis of hyperthyroidism. Lab results show a serum calcium level of 12.3 mg/dL. The nurse correctly anticipates which medication being ordered?
The client’s calcium levels are above normal and need to be lowered. Calcitonin lowers calcium levels. Calcium gluconate and calcium chloride would rise calcium levels. It is true that raising phosphate levels will act to reduce calcium levels but you would not administer sodium phosphate for this purpose. Sodium phosphate is an ingredient in Fleets® enema and used to empty the bowel.
A 45-year-old male client with history of coronary artery disease is admitted to the telemetry floor. The nurse would be most concerned about which lab result?
Normal troponin levels are less than 0.1, anything greater than that is an emergency and the pt needs to be evaluated for possible acute MI. Even if you don’t remember the exact values for these cardiac enzymes, know which are specific to the heart. Of the four results, troponins are the only one that relate to cardiac damage. Others would be CK, CK-MB, troponin—T and myoglobin.
A 4-year-old female is admitted to the pediatric wing with a diagnosis of Kawasaki disease. What would the nurse expect the laboratory results to reveal?
Kawasaki’s disease is an autoimmune disorder in children affecting the skin and mucous membranes. It is associated with high fever, strawberry tongue, peeling on hands and feet. Expected lab results are: Elevated WBCs, ESR and platelets.
A client under treatment for diabetes mellitus, type II is seen in the physician’s office for a routine checkup. The physician wants to determine how well the client has been managing their blood sugar over the past 3 months. Which laboratory test would the nurse expect to be ordered?
Hemoglobin A1c (Hgb A1c) is used to determine what a patient’s blood sugar has been—on average—over the past 3 months. This test determines how well an individual has been managing their sugar rather than a spot check. If a diabetic patient is compliant with a healthy diet, exercise and takes insulin or oral antidiabetic medications then the Hgb A1c will be low. A fasting blood glucose test is used to diagnose diabetes. Glucose tolerance test is more accurate and used when the fasting blood glucose test is inconclusive. Finger stick glucose check is generally performed prior to meals and bedtime to guide insulin dosage.
The nurse has received morning report and is prioritizing a four client assignment. Which client should be seen first?
CK-MB of 22 is very high and this patient needs to be evaluated for possible MI. Women often report atypical pain such as heartburn when experiencing an MI. The digoxin level is low and the dosage needs to be increased but this is not a priority. The theophylline level is therapeutic (same as Dilantin/phenytoin 10 – 20). The lithium level is also therapeutic and nausea is an expected side effect.
The nurse is reviewing laboratory results on her assignment and notes an elevated lactate dehydrogenase (LDH) but normal Troponin and CK-MB. The nurse correctly identifies this as a result of which disease?
Elevated lactate dehydrogenase (LDH) indicates damage to liver function. Acute viral hepatitis would is the only disease listed that would result in elevated LDH. MI would raise cardiac enzymes such as troponins, CK, CK-MB etc. Renal failure would raise creatinine and BUN. Addison’s disease would result in decreased sodium, chloride, bicarbonate and glucose; as well as increased hematocrit and potassium.
A patient is admitted with a diagnosis of syndrome of inappropriate antidiuretic hormone (SIADH). The nurse correctly identifies which finding as consistent with this diagnosis?
In SIADH, serum sodium and serum osmolality decrease AND urine sodium and urine osmolality increase. Essentially, blood becomes very dilute and urine becomes very concentrated. Excessive anti-diuretic hormone (ADH) is released; this tells the kidneys to hold onto water and concentrate urine. The name of the disease has all the clues to what lab results you should expect. Syndrome of Inappropriate Anti Diuretic Hormone, think TOO MUCH Anti-Diuretic Hormone. Too much ANTI-DIURETIC hormone should have the opposite effect of a diuretic. Instead of urinating out extra water, all that extra water is held on to. This dilutes the blood and causes electrolyte concentrations to decrease. Serum sodium is the most sensitive to these changes and so it is affected the most.
The patient is admitted to the surgical floor after a parathyroidectomy. The patient reports paresthesias and abdominal cramping. The nurse assesses a positive Chvostek’s sign. The nurse correctly identifies which electrolyte imbalance as responsible for these signs and symptoms?
The thyroid and parathyroid glands regulate calcium concentration in the blood. Parathyroid hormone increases calcium concentration whereas calcitonin (from the thyroid gland) decreases serum calcium. Removing the parathyroid gland would cause calcium concentration to decrease since calcitonin would continue to be released unopposed. Signs and symptoms of hypocalcemia include neuromuscular irritability (so twitching, tetany, cramping, increased reflexes, bronchospasm, positive Chvostek’s sign and Trousseau’s sign, seizures). EKG changes include QT prolongation. CATs go numb—Convulsions, Arrhythmias, Tetany and numbness/paresthesias in hands, feet, mouth and lips. (Ca is chemical symbol for calcium)
A CBC is run with the following results: WBC = 15,800 RBC = 5.2 Platelets = 320,000 Hemoglobin = 15.2 Hematocrit = 46% ESR = 32. The nurse correctly identifies which of the following as most likely?
Elevated WBC and ESR indicate acute infection. The other lab values are within normal limits.
An elderly client is admitted from the local nursing home. Routine labs are drawn. Which result requires immediate intervention by the nurse?
All the lab values are abnormal, however the sodium is critically elevated. Normal sodium is 135-145; sodium above 160 is considered critical. Acute dehydration is often diagnosed in patients admitted from nursing homes. Signs and symptoms of hypernatremia include: lethargy, weakness, irritability and edema. At critical levels, seizures and coma may occur
The nurse is reviewing morning labs on a 55-year-old male client who underwent a Whipple procedure the prior day. WBC are 10,500/mm3, RBCs are 3.2 M/mm3, hemoglobin is 7.5 g/dL hematocrit is 32%, platelets are 120,000/mm3. The nurse correctly anticipates the following order.
The nurse is reviewing morning labs on a 55-year-old male client whounder went a Whipple procedure the prior day. WBC is 10,500/mm3, RBCs are 3.2 M/mm3, hemoglobin is 7.5 g/dL, hematocrit is 32%, platelets are 120,000/mm3, and sedimentation rate is 15mm/hr. The nurse correctly anticipates the following order.
Hemoglobin less than 8.0 is usually an indication for transfusion of packed red blood cells. There is no indication of infection since WBC and ESR are both normal. An iron supplement would be indicated in iron deficient anemia but that will not correct the immediate problem Packed red blood cells are associated with less transfusion reactions than whole blood.
A client with history of diabetes is admitted with severe nausea and vomiting for several days. Which lab value is most important to report to the physician?
All these lab values are abnormal. Low electrolytes are expected with severe vomiting. However, a potassium less than 2.5 is critical and requires immediate intervention. Signs and symptoms of hypokalemia include muscle weakness, muscle pain, cramps, constipation. Severe hypokalemia results in flaccid paralysis and decreased reflexes. EKG changes include flat T-waves and large U-waves.
A client is admitted to the ER with altered mental status and deep rapid respirations. An arterial blood gas is drawn. What lab values would the nurse expect to be associated with these signs?
Deep rapid respirations cause acute/uncompensated respiratory alkalosis by blowing off too much CO2. Since carbon dioxide is an acid when dissolved in blood, blowing off extra CO2 will cause the blood to become alkaline. So as PaCO2 goes down, pH goes up. It takes 3-5 days for the kidneys to completely compensate for the respiratory alkalosis by lowering bicarbonate. Since bicarbonate (HCO3) is normal we know that this is an acute/uncompensated stage. Thus Acute/uncompensated respiratory alkalosis. Answer A is acute/uncompensated respiratory alkalosis Answer B is chronic/compensated metabolic alkalosis Answer D is chronic/compensated metabolic acidosis.
Which client should the nurse assess first?
Chloride of 78 is critically low and requires immediate attention. Normal chloride is 95-105. Hgb of 12.2 and hematocrit of 38% is on the lower end of normal. Serum digoxin of 1.2 is normal. Potassium of 3.4 is slightly low (normal is 3.5-5.)
The nurse is in a clinic and reviews the chart of a 55-year-old female client who takes Coumadin® daily. The PT is listed as 11 seconds. INR is 1.8. The nurse knows that this means what?
A normal or control PT is 9 to 12 seconds. A patient on coumadin therapy should have a PT 1.5 to 2.5 times this number, roughly double. So therapeutic would be at least greater than 14, in the 14-29 range. A normal or control INR is around 1. Therapeutic is 2 – 3, sometimes up to 4.5 (mechanical heart valves). Greater than 4.5 is ALWAYS TOO MUCH. Focus more on INR numbers if you are having difficulty memorizing the PT normal/therapeutic/critical levels. The INR is simpler to remember and most likely the INR and PT will be given together.
A client is seen in the emergency department with a finger stick blood glucose of 800 mg/dL and presumed diabetic ketoacidosis. The nurse prepares to administer an insulin bolus followed by a continuous insulin drip. Which of the following laboratory values must the nurse review prior to administering the insulin?
Treatment of diabetic ketoacidosis (DKA) by insulin can cause severe fluctuations in serum potassium. DKA on its own will cause dehydration and loss of potassium to urine by diuresis. Insulin shifts both glucose and potassium from blood into cells. This will cause serum potassium levels to drop even more. Serum potassium must be checked prior to administering an insulin bolus and regularly thereafter while the patient is on an insulin drip. If the potassium level is below 3.5 then the bolus or drip should be held until the potassium level is corrected.
The nurse knows that the therapeutic range for PTT in a client on heparin anticoagulation therapy is what?
Normal/control PTT is about 20 – 40 seconds. The therapeutic range for PTT in a client on heparin therapy is 1.5-2.5x the control. In general 60 – 90 sec is considered an appropriate range.
The physician suspects hypoxia in a client admitted to the ICU on a ventilator. Which of the following tests would the nurse expect to be ordered?
An arterial blood gas would be most appropriate to find the cause of hypoxia in a ventilated patient. It is used to evaluate gas exchange in the lungs as well as acid-base balance. A CBC and BMP are not directly related to respiratory status. Pulse oximetry is a non-invasive method to measure oxygen saturation but would not provide any additional information to assist with determining the cause of hypoxia.
An 8-year-old client is admitted for routine tonsillectomy. The nurse is providing pre-op education to the parents while the child is playing. Lab calls the nurse and reports that the serum potassium level is measured at 7.8 mEq/L. What would be the most appropriate nursing action?
Normal serum potassium in a child is the same as an adult (3.5 – 5.0). Symptoms of hyperkalemia include: muscle weakness, paralysis, nausea and diarrhea. EKG changes include tall peaked T-waves. A potassium of 7.8 would be life threatening and the client would be expected to show some symptoms. This patient is admitted for a routine procedure and there is no reason to suspect hyperkalemia. This along with the absence of any signs or symptoms of severe hyperkalemia should lead the nurse to question the results and have them redrawn. This is most likely pseudohyperkalemia caused by hemolysis during venipuncture. This occurs when blood is drawn with too much suction and/or through a too small gauge needle. Other causes include tourniquet that was left on too long or fist clenching during venipuncture. Allowing the sample to sit for too long before being analyzed can also cause a false high potassium level.
A client is admitted with end stage renal disease and receives dialysis every Monday, Wednesday and Friday. The client complains of constipation. The nurse would question an order for which of the following medications?
Milk of magnesia contains magnesium which is excreted by the kidneys. Patients with impaired renal function should avoid laxatives with magnesium. Fleets Enema ® which contains sodium phosphate should also be avoided in this patient population. In this case MiraLax® would be the first choice since it is the least invasive. If that were ineffective then a suppository and lastly an enema would be appropriate.
A client is admitted with fatigue, dizziness, nausea and a bronze skin tone. The lab report shows the following results: WBC 9.2 k/mm3, Hgb 13.5 mg/dL, Hct 55%, Sodium 129 mEq/L, Chloride 90 mEq/L, Potassium 5.9 mEq/L, blood glucose 62 mg/dL. The nurse correctly identifies these values as consistent with which disease process?
Addison’s disease is associated with fatigue, weakness, weight loss, abdominal pain, low blood pressure dehydration and a bronze tan. Laboratory findings include low sodium dehydration, elevated hematocrit, elevated potassium, and decreased blood glucose. Cushing’s disease is essentially the opposite of Addison’s and would have opposite lab values (elevated sodium, decreased potassium, elevated blood glucose).
A patient’s lab report shows total calcium level of 6.5 mEq/L. Which of the following blood tests, if reported at the same time as the total calcium, would lead the nurse to question whether the total calcium was a false low?
Low albumin levels will cause a false low calcium result. This is because some calcium is bound to albumin, however calcium bound to albumin is inert and unimportant. If albumin levels drop then total calcium will drop as well but ionized or free calcium will stay the same. Only ionized/free calcium is physiologically important. For this reason, lab reports will often show a “Corrected Calcium” that takes into account the albumin level. Answer A is wrong because an elevated phosphorus level would be expected in conjunction with low serum calcium
The nurse reviews ABG results of a patient who is complaining of shortness of breath following morning physical therapy exercise. The ABG was drawn before the exercise and revealed the following findings: pH 7.36, PaCO2 68 mm Hg, HCO3 34. SaO2 is now 87% on 2L oxygen via nasal cannula. What should be the nurse’s first priority?
The ABG indicates that this patient is normally in a state of chronic/compensated respiratory acidosis. This clinical picture is consistent with chronic COPD. Morning exercise with PT caused them to decompensate. Rest and pursed lip breathing would bring them back to their baseline. Rest would reduce the amount of carbon dioxide produced in the body and pursed lip breathing will help blow off more carbon dioxide. Answer B is wrong because these results are expected in a patient with COPD. Answer C is wrong because that would exacerbate the situation by increasing the carbon dioxide level. Breathing in a paper bag is appropriate for a patient with acute respiratory alkalosis who is hyperventilating. Answer D is wrong because increasing oxygen can be dangerous in patients with COPD since it can inhibit their respiratory drive. In this ABG the pH is normal but PaCO2 and HCO3 are off. This indicates that there is acidosis or alkalosis but it is chronic/compensated. The pH is closer to the acidic end so it is acidosis. Remember ROME—Respiratory Opposite, Metabolic Equal. The PaCO2 and HCO3 are both elevated but pH is decreased. This indicates respiratory process is responsible. Thus you have chronic/compensated respiratory acidosis. This patient is holding onto too much carbon dioxide. Extra CO2 causes the blood to become acidotic. The kidneys are compensating by increasing bicarbonate to bring the pH back into a normal range. If another ABG was drawn immediately after the exercise, the pH would likely have dropped even more and PaCO2 would have increased. The HCO3 would be about the same since it takes at least 12 hours for the kidneys to compensate.
A client is seen in the emergency department complaining of chest pain, diaphoresis and shortness of breath for the past 3 hours. Which laboratory result indicates acute myocardial infarction?
All four of these lab tests are cardiac biomarkers used to evaluate for myocardial infarction. CK-MB of 12 is the only one that is elevated. The other values are within normal limits. It is important to remember that aside from myoglobin, it takes several hours for results to become elevated. If a patient were to suddenly complain of chest pain and labs were immediately drawn the levels could be normal. This is why ‘serial cardiac labs’ are often ordered where a series of tests are done every 6 or 8 hours to observe for an upward trend. Troponins are considered the most accurate and best indicator for MI. They will begin to rise about 4 hours after an acute MI and peak 12-24 hours gradually decreasing and returning to normal in 1 – 2 weeks. CK and CK-MB begin to rise in 4-6 hours peak in 12 – 24 hours and gradually decrease until back to normal in 2 – 4 days. Myoglobin begins to rise in 1 – 3 hours, peaks in 6 – 10 hours and back to normal in 12 – 24 hours. If a patient reports having an MI one week ago and now complains of chest pain again, you would look at CK or CK-MB because they should have already returned to normal from the first MI, Troponins will still be elevated from the first MI.
