Chapter 21 Laboratory Medicine 1 What may cause a false lab report of hyperkalemia? Hemolysis of the blood sample. Repeat the test if a high value does not make sense (e.g., high level with no electrocardiogram [ECG] changes or symptoms). 2 What can cause a “false” hyponatremia (pseudohyponatremia)? Pseudohyponatremia may be caused by hyperglycemia, hyperproteinemia, or hyperlipidemia. The hyponatremia resolves with correction of the glucose, lipid, or protein levels. 3 What may result from rapid correction of hyponatremia? Brainstem damage (central pontine myelinolysis). For this reason you should generally not give hypertonic saline to correct hyponatremia except in severe or symptomatic cases, and then it should be given in limited quantities. 4 What effect do serum acidosis and serum alkalosis have on potassium and calcium levels? Alkalosis may cause hypokalemia and symptoms of hypocalcemia (perioral numbness, tetany) as a result of cellular shift, whereas acidosis may cause hyperkalemia by the same mechanism. Correction of acid-base status will correct the potassium and calcium derangements. 5 Other than pancreatic disease, what else can cause elevated levels of amylase and lipase? Damage of the salivary glands or bowel, renal failure, and ruptured tubal pregnancy may cause amylase and lipase elevations. Elevation of both amylase and lipase in the same patient, however, is usually caused by pancreatitis. The boards may try to trick you with an isolated elevation of amylase. Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: Radiology Endocrinology Pulmonology Gastroenterology Stay updated, free articles. Join our Telegram channel Join Tags: USMLE Step 2 Secrets Apr 8, 2017 | Posted by admin in NURSING | Comments Off on Laboratory Medicine Full access? Get Clinical Tree
Chapter 21 Laboratory Medicine 1 What may cause a false lab report of hyperkalemia? Hemolysis of the blood sample. Repeat the test if a high value does not make sense (e.g., high level with no electrocardiogram [ECG] changes or symptoms). 2 What can cause a “false” hyponatremia (pseudohyponatremia)? Pseudohyponatremia may be caused by hyperglycemia, hyperproteinemia, or hyperlipidemia. The hyponatremia resolves with correction of the glucose, lipid, or protein levels. 3 What may result from rapid correction of hyponatremia? Brainstem damage (central pontine myelinolysis). For this reason you should generally not give hypertonic saline to correct hyponatremia except in severe or symptomatic cases, and then it should be given in limited quantities. 4 What effect do serum acidosis and serum alkalosis have on potassium and calcium levels? Alkalosis may cause hypokalemia and symptoms of hypocalcemia (perioral numbness, tetany) as a result of cellular shift, whereas acidosis may cause hyperkalemia by the same mechanism. Correction of acid-base status will correct the potassium and calcium derangements. 5 Other than pancreatic disease, what else can cause elevated levels of amylase and lipase? Damage of the salivary glands or bowel, renal failure, and ruptured tubal pregnancy may cause amylase and lipase elevations. Elevation of both amylase and lipase in the same patient, however, is usually caused by pancreatitis. The boards may try to trick you with an isolated elevation of amylase. Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: Radiology Endocrinology Pulmonology Gastroenterology Stay updated, free articles. Join our Telegram channel Join
