Critical Care: Chapter 19: Endocrine

18. A patient presents to the emergency department with suspected thyroid storm. The nurse should be alert to which of the following cardiac rhythms while providing care to this patient? a. Atrial fibrillation b. Idioventricular rhythm c. Junctional rhythm d. Sinus bradycardia

ANS: A Increased heart rate and tachydysrhythmia, including atrial fibrillation, may accompany thyroid storm. Bradycardiac rhythms may be suggestive of hypothyroidism.

17. The most significant clinical finding of acute adrenal crisis associated with fluid and electrolyte balance is: a. fluid volume excess. b. hyperglycemia. c. hyperkalemia d. hypernatremia

ANS: C Adrenal insufficiency may be characterized by inadequate amounts of cortisol and aldosterone. Aldosterone acts to retain sodium, resulting is water retention and potassium loss. Inadequate levels of aldosterone therefore result in hyponatremia, fluid loss, and hyperkalemia. Inadequate cortisol levels may cause weight loss, weakness, and hypoglycemia. Fluid volume deficit may accompany adrenal crisis as a result of sodium loss from decreases in cortisol and aldosterone. Hypoglycemia may accompany adrenal crisis as a consequence of inadequate amounts of cortisol, which limits gluconeogenesis. Hyponatremia may accompany adrenal crisis because of sodium losses secondary to aldosterone insufficiency that often accompanies the condition.

5. The nurse is assigned to care for a patient who presented to the emergency department with diabetic ketoacidosis. A continuous insulin intravenous infusion is started, and hourly bedside glucose monitoring is ordered. The targeted blood glucose value after the first hour of therapy is: a. 70 to 120 mg/dL. b. a decrease of 25 to 50 mg/dL compared with admitting values. c. a decrease of 50 to 75 mg/dL compared with admitting values. d. less than 200 mg/dL.

ANS: C Initial insulin infusions should be administered with a target blood glucose reduction of 50 to 75 mg/dL per hour. Decreases of less than this rate may be associated with inadequate insulin replacement and allow for the persistence of the ketotic state. Rapid reductions of blood glucose may precipitate life-threatening cerebral edema; thus, controlled reduction of glucose is required.

3. Which of the following laboratory values would be more common in patients with diabetic ketoacidosis? a. Blood glucose >1000 mg/dL b. Negative ketones in the urine c. Normal anion gap d. pH 7.24

ANS: D A pH of 7.24 is indicative of an acidotic state that may accompany diabetic ketoacidosis. Glucose values of more than 1000 mg/dL are more commonly associated with hyperosmolar hyperglycemic syndrome. Diabetic ketoacidosis is associated with positive urine ketones and an increased anion gap.

8. The nurse is providing postoperative care to a patient who underwent a transsphenoidal hypophysectomy for a benign pituitary tumor. The nurse administers replacement hydrocortisone, thyroid hormone, and vasopressin. The nurse evaluates that the vasopressin replacement is effective when: a. the patient's blood glucose is 110 mg/dL. b. the patient maintains a core body temperature of 98.2° F (36.8° C). c. the patient's urine specific gravity decreases. d. 2 liters of urine are produced in a 24-hour period.

ANS: D Vasopressin is administered to replace antidiuretic hormone following a hypophysectomy. Other life-sustaining hormones such as cortisol and thyroid hormone that involve a feedback system between the pituitary gland and the target gland also must be replaced. Vasopressin produces elevation of blood pressure, causes retention of fluid, and reduces urine output. The result is a decrease in serum sodium and serum osmolality secondary to hemodilution and increase in urine specific gravity. Blood glucose control is not affected by vasopressin; cortisol would directly affect blood glucose. Core body temperature would be most directly affected by thyroid hormone. Urine specific gravity would increase, not decrease, following vasopressin administration.

15. A 20-year-old female with a history of type 1diabetes and an eating disorder is found unconscious. In the emergency department, the following lab values are obtained: Glucose648 mg/dL pH6.88 PaCO220 mm Hg PaO295 mm Hg HCO3- undetectable Anion gap>31 Na+127 mEq/L K+ 3.5 mEq/L Creatinine1.8 mg/dL After the patient's airway and ventilation have been established, the next priority for this patient is: a. administration of a 1-L normal saline fluid bolus. b. administration of 0.1 unit of regular insulin IV push followed by an insulin infusion. c. administration of 20 mEq KCl in 100 mL. d. IV push administration of 1 amp of sodium bicarbonate.

ANS: A After airway is established, the next priority in management of DKA is fluid resuscitation with 1 liter of normal saline over 1 hour. The fluid resuscitation should begin prior to administration of insulin. Potassium may be added to fluid replacement bags after the first liter of normal saline has infused, provided that the serum potassium is greater than 3.3 mEq/L. Although bicarbonate replacement is indicated in this clinical situation, the bicarbonate is administered by infusion, not by IV push, until the pH exceeds 7.0.

27. The nurse is caring for a patient who suffered a head trauma following a fall. The patient's heart rate is 112 beats/min and blood pressure is 88/50 mm Hg. The patient has poor skin turgor and dry mucous membranes. The patient is confused and restless. The following laboratory values are reported: serum sodium is 115 mEq/L; blood urea nitrogen (BUN) 50 mg/dL; and creatinine 1.8 mg/dL. The findings are consistent with which disorder? a. Cerebral salt wasting b. Diabetes insipidus c. Syndrome of inappropriate secretion of antidiuretic hormone d. Thyroid storm

ANS: A Cerebral salt wasting may occur after head trauma and is characterized by low sodium in the face of classic physical and laboratory signs of fluid volume deficit or dehydration, including tachycardia, hypotension, dry mucous membranes, weight loss, and poor skin turgor. The patient also may experience the classic signs of hyponatremia, including a serum sodium less than 135 mg/dL, confusion, lethargy, seizures, and coma. Diabetes insipidus is characterized by clinical signs of dehydration with elevated serum sodium. SIADH is characterized by hyponatremia and fluid volume overload. Thyroid storm would not directly affect sodium levels.

7. The nurse is caring for a 27-year-old patient with a diagnosis of head trauma. The nurse notes that the patient's urine output has increased tremendously over the past 18 hours. The nurse suspects that the patient may be developing: a. diabetes insipidus. b. diabetic ketoacidosis. c. hyperosmolar hyperglycemic syndrome. d. syndrome of inappropriate secretion of antidiuretic hormone.

ANS: A Diabetes insipidus results in large volumes of urine; dehydration and hypovolemia can result. Head trauma and resulting increased intracranial pressure are potential causes of diabetes insipidus. High urine output following head trauma is associated with diabetes insipidus. Even though hyperosmolar hyperglycemic syndrome results in osmotic diuresis, the cause is a deficiency in insulin in type 2 diabetes, not head trauma. SIADH may occur with head trauma but results in reduced urine output and, potentially, hypervolemia.

21. Which of the following would be seen in a patient with myxedema coma? a. Decreased reflexes b. Hyperthermia c. Hyperventilation d. Tachycardia

ANS: A Myxedema coma is characterized by a hypometabolic state, and all body functions are slowed including cardiovascular function, decreased gastrointestinal mobility, cold intolerance, and diminished reflexes. Hyperthermia is characteristic of thyroid storm. Hyperventilation is characteristic of thyroid storm and diabetic ketoacidosis. Tachycardia is characteristic of thyroid storm.

6. A patient has been on daily, high-dose glucocorticoid therapy for the treatment of rheumatoid arthritis. His prescription runs out before his next appointment with his physician. Because he is asymptomatic, he thinks it is all right to withhold the medication for 3 days. What is likely to happen to this patient? a. He will go into adrenal crisis. b. He will go into thyroid storm. c. His autoimmune disease will go into remission. d. Nothing; it is appropriate to stop the medication for 3 days.

ANS: A Patients on long-term corticosteroid therapy are at high risk for adrenal crisis, because therapy suppresses the endogenous production of steroids. Adrenal crisis may be precipitated by sudden withdrawal of glucocorticoid therapy. Thyroid storm may occur when antithyroid medications are suddenly withdrawn. Rheumatoid arthritis is likely to exacerbate with the withdrawal of glucocorticoids. Adrenal crisis may occur shortly after withdrawal of glucocorticoids.

4. What psychosocial factors may potentially contribute to the development of diabetic ketoacidosis? (Select all that apply.) a. Altered sleep/rest patterns b. Eating disorder c. Exposure to influenza d. High levels of stress e. Lack of financial resources

ANS: A, B, D, E Psychosocial factors may lead to changes in diabetes self-management practices that precipitate diabetic ketoacidosis. Eating disorders may complicate 20% of recurrent cases of DKA in young women. Changes in sleep patterns and psychosocial stressors may lead to increased insulin demands in the face of declining self-care practices. Financial and time limitations impacted the ability to monitor for changes in control. Exposure to influenza is a physiological factor; it would not be a psychosocial factor associated with DKA.

5. Factors associated with the development of nephrogenic diabetes insipidus include which of the following? (Select all that apply.) a. Heredity b. Medications, including phenytoin (Dilantin) and lithium carbonate c. Meningitis d. Pituitary tumors e. Sickle cell disease

ANS: A, B, E Nephrogenic diabetes insipidus occurs when adequate amounts of antidiuretic hormone are produced with limited renal response. Causative factors for nephrogenic diabetes insipidus are heredity, preexisting renal disease, multisystem diseases such as multiple myeloma and sickle cell disease, chronic electrolyte disturbances, and medications. Meningitis may result in neurogenic diabetes insipidus. Pituitary tumors may result in neurogenic diabetes insipidus.

2. Mechanisms for development of diabetes insipidus include which of the following? (Select all that apply.) a. ADH deficiency b. ADH excess c. ADH insensitivity d. ADH replacement therapy e. Water deprivation

ANS: A, C Diabetes insipidus is caused by either a deficiency in ADH production (neurogenic) or impaired renal response to ADH (nephrogenic). ADH excess is characteristic of syndrome of inappropriate secretion of antidiuretic hormone. ADH replacement therapy is a treatment for neurogenic diabetes insipidus. Water deprivation would result in increased ADH secretion and further augment dehydration associated with diabetes insipidus.

1. Which of the following are appropriate nursing interventions for the patient in myxedema coma? (Select all that apply.) a. Administer levothyroxine (Synthroid) as ordered. b. Encourage the intake of foods high in sodium. c. Initiate passive rewarming interventions. d. Monitor airway and respiratory effort. e. Monitor urine osmolality.

ANS: A, C, D Myxedema coma is a severe manifestation of hypothyroidism. Treatment entails replacement of thyroid hormone, airway management related to respiratory depression and potential airway obstruction related to tongue edema, thermoregulation, management of edema and congestive heart failure symptoms, and patient education. Edema may accompany myxedema and necessitate use of sodium restriction. Urine osmolality is monitored in conditions that affect antidiuretic hormone levels.

16. Acute adrenal crisis is caused by: a. acute renal failure. b. deficiency of corticosteroids. c. high doses of corticosteroids. d. overdose of testosterone.

ANS: B An adrenal crisis occurs because of a lack of corticosteroids. This may be due to lack of endogenous cortisol production, lack of ACTH production, or inhibition of natural cortisol production by exogenous cortisol administration. Acute renal failure would not be associated with adrenal crisis. High doses of corticosteroids are associated with Cushing's syndrome. Testosterone overdose would not be associated with adrenal crisis. Steroid hormones may possess some corticoid properties.

4. Which of the following is a high-priority nursing diagnosis for both diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome? a. Activity intolerance b. Fluid volume deficient c. Hyperthermia d. Impaired nutrition, more than body requirements

ANS: B Both diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome result in dehydration and hypovolemia; therefore, fluid volume deficit is a priority nursing diagnosis. Even though activity intolerance is a potential nursing diagnosis related to the fatigue associated with metabolic changes in hyperglycemic conditions, it is not a first priority. Hyperthermia is associated with thyroid crisis. Although overweight and obesity are risk factors for type 2 diabetes, during metabolic crisis, the patient has inadequate energy available to tissues because of limited availability and poor utilization of insulin.

1. A patient with type 1 diabetes who is receiving a continuous subcutaneous insulin infusion via an insulin pump contacts the clinic to report mechanical failure of the infusion pump. The nurse instructs the patient to begin monitoring for signs of: a. adrenal insufficiency. b. diabetic ketoacidosis. c. hyperosmolar, hyperglycemic state. d. hypoglycemia.

ANS: B If the insulin pump fails, the patient with type 1 diabetes will have a complete interruption of insulin delivery; diabetic ketoacidosis will occur. Adrenal insufficiency would not result from insulin pump failure. Hyperosmolar, hyperglycemic state is a hyperglycemic complication associated with type 2 diabetes; this patient has type 1 diabetes. Interruption of insulin delivery in type 1 diabetes would result in hyperglycemia, not hypoglycemia.

22. The nurse is caring for a patient who underwent pituitary surgery 12 hours ago. The nurse will give priority to monitoring the patient carefully for which of the following? a. Congestive heart failure b. Hypovolemic shock c. Infection d. Volume overload

ANS: B Pituitary surgery or manipulation of the pituitary stalk during surgery may precipitate diabetes insipidus. Profound diuresis that accompanies diabetes insipidus may result in hypovolemic shock. Fluid volume deficit, not overload, accompanies diabetes insipidus. Increased risk of infection may accompany hyperglycemia and elevated cortisol levels. Fluid volume overload is more characteristic of SIADH.

28. A patient with newly diagnosed type 1 diabetes is being transitioned from an infusion of intravenous (IV) regular insulin to an intensive insulin therapy regimen of insulin glargine (Lantus) and insulin aspart (NovoLog). How should the nurse manage this transition in insulin delivery? a. Administer the insulin glargine and continue the IV insulin infusion for 24 hours. b. Administer the insulin glargine and discontinue the IV infusion in several hours. c. Discontinue the IV infusion and administer the insulin aspart with the next meal. d. Discontinue the IV infusion and administer the Lantus insulin at bedtime.

ANS: B Subcutaneous insulin should be administered 1 to 4 hours before discontinuing the intravenous infusion to allow the patient to reach adequate plasma insulin levels to prevent redevelopment of DKA. Continuation of the insulin infusion in conjunction with the long-acting insulin glargine would result in hypoglycemia. Discontinuation of intravenous insulin prior to administration of subcutaneous insulin would result in reoccurrence of DKA in a patient with type 1 diabetes.

14. An individual with type 2 diabetes who takes glipizide (Glucotrol) to control her blood glucose has begun a formal exercise program at a local gym. While exercising on the treadmill, she becomes pale, diaphoretic, and shaky. She has a headache and feels as though she is going to pass out. What is the individual's priority action? a. Drink additional water to prevent dehydration. b. Eat something with 15 g of simple carbohydrates. c. Go to the first aid station to have glucose checked. d. Take another dose of the oral agent.

ANS: B The patient is displaying classic symptoms of hypoglycemia. The patient is on sulfonylurea therapy, which carries the risk of hypoglycemia. The walking may be more exercise than she is used to and may thereby cause hypoglycemia. Fifteen grams of carbohydrate is appropriate for initial management of hypoglycemia. Hypoglycemia does not place the patient at risk for dehydration. The patient requires immediate treatment and could pass out while going to the first aid station. It cannot be assumed that the gym has access to diabetes treatment supplies. Additional doses of oral diabetes medications should not be taken without consulting the healthcare team. An additional dose of glipizide could promote further hypoglycemia.

6. The nurse has been assigned the following patients. Which patients require assessment of blood glucose control as a nursing priority? (Select all that apply.) a. 18-year-old male who has undergone surgical correction of a fractured femur b. 29-year-old female who is undergoing evaluation for pheochromocytoma c. 43-year-old male with acute pancreatitis who is receiving total parenteral nutrition (TPN) d. 62-year-old morbidly obese female who underwent a hysterectomy for ovarian cancer e. 72-year-old female who is receiving intravenous (IV) steroids for an exacerbation of chronic obstructive pulmonary disease (COPD)

ANS: B, C, D, E Risk factors for development of stress-induced hyperglycemia are a prior history of diabetes or hyperglycemia; obesity; pancreatitis; cirrhosis; glucocorticoids; excess epinephrine; advanced age; nutrition support; and various medications. The young male with the fractured femur is at low risk for stress-induced hyperglycemia.

3. A college student was admitted to the emergency department after being found unconscious by a roommate. The roommate informs emergency medical personnel that the student has diabetes and has been experiencing flulike symptoms, including vomiting, since yesterday. The patient had been up all night studying for exams. The patient used the last diabetes testing supplies 3 days ago and has not had time to go to the pharmacy to refill prescription supplies. Based upon the history, which laboratory findings would be anticipated in this client? (Select all that apply.) a. Blood glucose 43 mg/dL b. Blood glucose 524 mg/dL c. HCO3- 10 mEq/L d. PaCO2 37 mm Hg e. pH 7.23

ANS: B, C, E The patient is presenting with laboratory evidence of diabetic ketoacidosis. Diabetic ketoacidosis is characterized by hyperglycemia and low bicarbonate levels, low CO2, and low pH. A blood glucose of 43 mg/dL is indicative of hypoglycemia. The reported carbon dioxide level is normal and is not consistent with acute DKA, for which compensatory tachypnea would be expected along with a low PaCO2.

7. A patient with long-standing type 1 diabetes presents to the emergency department with a loss of consciousness and seizure activity. The patient has a history of renal insufficiency, gastroparesis, and peripheral diabetic neuropathy. Emergency personnel reported a blood glucose of 32 mg/dL on scene. When providing discharge teaching for this patient and family, the nurse instructs on the need to do which of the following? (Select all that apply.) a. Administer glucagon 1 mg intramuscularly any time the blood glucose is less than 70 mg/dL. b. Administer 15 grams of carbohydrate orally for severe episodes of hypoglycemia. c. Discontinue the insulin pump by removing the infusion set catheter. d. Increase home blood glucose monitoring and report patterns of hypoglycemia to the provider. e. Perform blood glucose monitoring before exercising and driving.

ANS: B, D, E This patient experienced a severe hypoglycemic episode. The patient is at risk for this because of a history of autonomic neuropathy as evidenced by gastroparesis, which causes erratic gastric emptying and glucose absorption, and renal insufficiency, which can result in erratic clearance of insulin. Patients with hypoglycemia unawareness should increase blood glucose monitoring; carry a glucagon emergency kit and instruct a family member of friend on administration; monitor before high-risk activities such as driving and exercising; and use caution with alcohol ingestion. Glucagon or 50% dextrose is administered for severe hypoglycemic episodes when a patient is unconscious or extremely uncooperative. Oral glucose replacement may be dangerous in a severe reaction because of the risk of aspiration. Mild and moderate hypoglycemic reactions should be managed with oral glucose replacement. Insulin pump therapy may be suspended temporarily during a hypoglycemic episode but should not be discontinued. The infusion set catheter should not be removed during a hypoglycemic episode.

10. A 32-year-old patient is admitted to the critical care unit with a diagnosis of diabetic ketoacidosis. Following aggressive fluid resuscitation and intravenous (IV) insulin administration, the blood glucose begins to normalize. In addition to glucose monitoring, which of the following electrolytes requires close monitoring? a. Calcium b. Chloride c. Potassium d. Sodium.

ANS: C Potassium must be closely monitored. In the early stages of diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome, the potassium value is often high, but it may lower to critical levels once fluid balance has been restored and glucose has returned to more normal levels. Insulin administration used in the treatment of diabetic ketoacidosis further promotes lowering of potassium as the electrolyte is relocated to the cellular bed. Calcium levels do not drastically change in hyperosmolar states and are not a primary concern unless phosphate replacement is initiated. Chloride levels typically follow sodium levels and normalize with fluid replacement. Sodium levels may initially be elevated as a result of dehydration but will be corrected with fluid replacement.

24. Which of the following laboratory values would be found in a patient with syndrome of inappropriate secretion of antidiuretic hormone? a. Fasting blood glucose 156 mg/dL b. Serum potassium 5.8 mEq/L c. Serum sodium 115 mEq/L d. Serum sodium 152 mEq/L

ANS: C SIADH causes a dilutional hyponatremia, and central nervous system symptoms can occur. A low serum sodium (below 135 mEq/L) may accompany the syndrome. Glucose elevation is not a classic sign of SIADH. Hyperkalemia does not accompany the dilutional hyponatremia of SIADH. Serum sodium levels are typically lower in the dilutional hyponatremia that accompanies SIADH.

25. A patient with pancreatic cancer has been admitted to the critical care unit with clinical signs consistent with syndrome of inappropriate secretion of antidiuretic hormone. The nurse anticipates that clinical management of this condition will include: a. administration of 3% normal saline. b. administration of exogenous vasopressin. c. fluid restriction. d. low sodium diet.

ANS: C The first treatment of this condition is volume restriction; other treatments may not be needed if restrictions work. Extreme fluid restrictions (800 to 1000 mL/day) may be required in the treatment of SIADH. Hypertonic saline administration may be used to treat severe hyponatremia (serum sodium < 110 mEq/L) but is not used in most cases. The administration of hypertonic saline carries significant risk. Vasopressin replacement would provide additional ADH and further complicate SIADH. Sodium replacement may be required to treat the hemodilution associated with SIADH.

23. The nurse is caring for a patient with head trauma who was admitted to the surgical intensive care unit following a motorcycle crash. What is an important assessment that will assist the nurse in early identification of an endocrine disorder commonly associated with this condition? a. Daily weight b. Fingerstick glucose c. Lung sound auscultation d. Urine osmolality

ANS: D Diabetes insipidus may result from traumatic brain injury. It results in passage of large volumes of dilute urine. Urine osmolality is low in individuals with diabetes insipidus, and urine specific gravity assessments should be incorporated into the care of at-risk patients. Even though daily weight monitoring is important in the assessment of fluid balance disorders, it is not specific in determining cause. Urine specific gravity measuring would be a more specific means of identifying diabetes insipidus. Blood glucose values would be abnormal in diabetes mellitus but not diabetes insipidus. Changes in breath sounds accompany fluid overload states such as SIADH. Diabetes insipidus is a hypovolemic condition.

2. Which of the following patients is at the highest risk for hyperosmolar hyperglycemic syndrome? a. An 18-year-old college student with type 1 diabetes who exercises excessively b. A 45-year-old woman with type 1 diabetes who forgets to take her insulin in the morning c. A 75-year-old man with type 2 diabetes and coronary artery disease who has recently started on insulin injections d. An 83-year-old, long-term care resident with type 2 diabetes and advanced Alzheimer's disease who recently developed influenza

ANS: D Hyperosmolar hyperglycemic syndrome is more common in type 2 diabetes; influenza is a stressor that would result in further increases in blood sugar. Some individuals with advanced Alzheimer's disease cannot communicate thirst needs and may be incontinent, making hypertonic fluid loss more difficult to estimate. Uncontrolled type 1 diabetes is associated with diabetic ketoacidosis. Interruption of insulin delivery related to a missed insulin dose in type 1 diabetes creates a situation of absolute insulin deficiency in type 1 diabetes and is associated with diabetic ketoacidosis. A patient with type 2 diabetes who is new to insulin is at risk for hypoglycemia.

12. In hyperosmolar hyperglycemic syndrome, the laboratory results are similar to those of diabetic ketoacidosis, with three major exceptions. What differences would you expect to see in patients with hyperosmolar hyperglycemic syndrome? a. Lower serum glucose, lower osmolality, and greater ketosis b. Lower serum glucose, lower osmolality, and milder ketosis c. Higher serum glucose, higher osmolality, and greater ketosis d. Higher serum glucose, higher osmolality, and no ketosis

ANS: D In patients with hyperosmolar hyperglycemic syndrome (HHS), glucose is higher; osmotic diuresis is greater, resulting in higher osmolality; and ketosis is usually absent. Glucose values in HHS are typically higher than those of diabetic ketoacidosis and are not typically accompanied by ketosis.

26. The nurse is providing insulin education for an elderly patient with longstanding diabetes. An order has been written for the patient to take 20 units of insulin glargine (Lantus) at 10 PM nightly. The nurse should instruct the patient that the peak of the insulin action for this agent is: a. 0200. b. 0400. c. 0800. d. peakless.

ANS: D Insulin glargine (Lantus) is a long-acting insulin that has no specific peak in action. The remaining times are associated with peaks of other short-acting and intermediate-acting insulin products.

9. In the management of diabetic ketoacidosis and hyperosmolar hyperglycemic syndrome, when is an intravenous (IV) solution that contains dextrose started? a. Never; normal saline is the only appropriate solution in diabetes management b. When the blood sugar reaches 70 mg/dL c. When the blood sugar reaches 150 mg/dL d. When the blood glucose reaches 250 mg/dL

ANS: D Normal saline is the best initial fluid choice for management of hyperglycemic states. However, when the glucose reaches about 250 mg/dL, solutions containing dextrose are added to prevent hypoglycemia. Hypotonic solutions are required to replace intracellular fluid deficits, and dextrose is required to prevent hypoglycemia later when glucose levels reach initial targets. A glucose level of 70 mg/dL is suggestive of hypoglycemia and would require oral glucose replacement, a 50% dextrose bolus, or glucagon administration.

11. A patient is admitted to the oncology unit with a small cell lung carcinoma. During the admission, the patient is noted to have a significant decrease in urine output accompanied by shortness of breath, edema, and mental status changes. The nurse is aware that this clinical presentation is consistent with: a. adrenal crisis. b. diabetes insipidus. c. myxedema coma. d. syndrome of inappropriate secretion of antidiuretic hormone (SIADH).

ANS: D SIADH may be induced by ectopic sources of antidiuretic hormone, including small cell lung carcinoma. The clinical presentation of a dilutional hypervolemia is consistent with SIADH. Adrenal crisis is characterized by fluid loss if secondary to decreased cortisol and aldosterone levels resulting in sodium loss. Diabetes insipidus is characterized by increased urine output and is not typically caused by lung tumors. Myxedema coma, although characterized by facial and peripheral edema, does not result from small cell lung carcinoma.

20. A patient presents to the emergency department (ED) with the following clinical signs: Pulse: 132 beats/min Blood pressure: 88/50 mm Hg Respiratory rate: 32 breaths/min Temperature: 104.8° F Chest x-ray: Findings consistent with congestive heart failure Cardiac rhythm: Atrial fibrillation with rapid ventricular response These signs are consistent with which disorder? a. Adrenal crisis b. Myxedema coma c. Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) d. Thyroid storm

ANS: D Tachycardia, vascular collapse, rapid cardiac rhythms, congestive heart failure, and severe hyperthermia are consistent with the clinical manifestations of the hypermetabolic state of thyroid storm. Adrenal insufficiency presents with weakness, fatigue, weight loss, anorexia, abdominal pain, and hyperpigmentation. Myxedema coma is an extreme form of hypothyroidism and is characterized by signs of hypometabolism, including bradycardia, hypotension, hypothermia, cold intolerance, and neurological sluggishness. SIADH is characterized by fluid retention, hyponatremia, and hemodilution. Heat intolerance and atrial fibrillation are not typical characteristics of the condition.

19. An elderly female patient has presented to the emergency department with altered mental status, hypothermia, and clinical signs of heart failure. Myxedema is suspected. Which of the following laboratory findings support this diagnosis? a. Elevated adrenocorticotropic hormone b. Elevated cortisol levels c. Elevated T3 and T4 d. Elevated thyroid-stimulating hormone

ANS: D Thyroid hormones are low in myxedema. Thyroid-stimulating hormone is usually high in relation to the feedback mechanisms for hormone regulation if myxedema is caused by primary hypothyroidism. Elevated adrenocorticotropic hormone may be seen in pituitary conditions or adrenal insufficiency. Elevated cortisol levels accompany Cushing's syndrome. Elevated T3 and T4 levels are consistent with hyperthyroidism.

13. Which of the following statements is true about the medical management of diabetic ketoacidosis? a. Serum lactate levels are used to guide insulin administration. b. Sodium bicarbonate is a first-line medication for treatment. c. The degree of acidosis is assessed through continuous pulse oximetry. d. Volume replacement and insulin infusion often correct the acidosis.

ANS: D Volume replacement promotes hemodilution in the face of a hyperosmolar state. Insulin administration promotes entry of glucose into cells and relieves ketosis. As volume is replaced and glucose normalizes, the acidosis often resolves. Insulin administration, not lactate levels, is guided by blood glucose values. Sodium bicarbonate is only administered to correct severe acidosis (pH < 7.1). Degree of acidosis is assessed through arterial blood gas readings and serum ketone levels.