SwedishAmerican Reference Laboratory Chemistry Specimen Collection Manual

Transcription

1 SwedishAmerican Reference Laboratory Chemistry Specimen Collection Manual General specimen collection (blood) 2 General specimen collection (urine) 2 ACTH stimulation test 3 Breath testing (Lactose, Lactulose, Fructose) 3 Dexamethasone suppression test 4 Urine drugs of abuse screen 4 Glucose tolerance testing 4 Therapeutic drug collection times 5 1

2 CHEMISTRY/URINALYSIS General specimen collection (blood): For all questions regarding specimen container or minimum volume, please call Customer Service prior to collection of the specimen. As a general rule, the patient should be fasting for most chemistry tests. Fasting is defined as nothing to eat or drink (except plain water) for 8-12 hours prior to specimen collection. General specimen collection (urine): Random Specimens Specimens for routine urinalysis should ideally be collected as early morning specimens. They should be collected and delivered to the laboratory as soon as possible. Urine specimens should be refrigerated unless analyzed immediately. 24 hour Urine Specimens The accurate, careful collection of a 24 hour specimen is of the utmost importance. Laboratory determinations done on incomplete or inappropriately collected specimens may be harmful to the patient because of the erroneous value obtained. All specimen bottles must be labeled with patient s first and last name, height, weight, date of birth or medical record number. Please note any drug or dietary restrictions specific to the test being collected. At the hour you select to start the 24 hour period, urinate and discard this specimen. From that time, collect all urine passed into a clean container and transfer to the 24 hour urine collection bottle. Refrigerate and return to the laboratory as soon as the 24 hour period has ended. Multiple specimen containers should be labeled as such (i.e., 1 of 3, 2 of 3, etc.) to avoid testing on incomplete collections. 2

3 ACTH (Cosyntropin) Stimulation Test The administration of ACTH in a normal individual will result in a rapid rise in serum cortisol level. Patients with adrenal destruction (Addison s disease) will show no change in serum cortisol level after ACTH administration. Patients with atrophy of the adrenal cortex due to exogenous glucocorticoid treatment or dysfunction of the pituitary gland or hypothalamus may show a slight rise in serum cortisol level, but not one of normal magnitude. 1. A baseline serum cortisol level is drawn µg cosyntropin is given intramuscularly or intravenously 3. Serum cortisol levels are drawn at 30 and 60 minutes Breath Testing for Carbohydrate Intolerance: Lactose Fructose Lactulose A hydrogen breath test provides information about the digestion of certain sugars such as milk sugar (lactose) or fruit sugar (fructose). One example is the use of this test to detect lactose intolerance, a disorder in which people have symptoms from abnormal digestion of lactose, a substance in many foods including milk and ice cream. The test is also used for detecting abnormal growth of bacteria within the small bowel by having the patient ingest lactulose. Bacterial overgrowth can cause a variety of symptoms including diarrhea, bloating, gas, and abdominal cramps. Breath testing can only be performed at the Outpatient Center at SwedishAmerican Hospital, or the Outpatient Laboratory at SwedishAmerican Medical Center, Belvidere. Please schedule this test with Central Scheduling. Before the test: Breath testing takes approximately 2-4 hours in the Outpatient Center The patient may not take any antibiotics one week prior to the test. o Antibiotics may kill the normal bacteria in the small intestine, which will interfere with the test. Other medications may be taken. The patient must be fasting at least 8 hours prior to the test, as well as during the test. o Any food or beverage (other than water) can interfere with absorption of the test solution. Plain water before and during the test is allowed. The patient may not smoke one hour before or during the test. o Chemicals in tobacco smoke interfere with the instrument used to measure the hydrogen in breath samples. 3

4 Dexamethasone Suppression Test (overnight): Dexamethasone, a cortisol analogue, suppresses adrenocorticotropic hormone and cortisol production in normal subjects, but not in patient s with Cushing s syndrome. 1. One milligram of dexamethasone is given orally at 11:00 p.m. 2. A serum cortisol level is drawn at 8:00 a.m. the next morning. Drug Abuse Testing Toxicology The following drug classes will be analyzed by the laboratory at SwedishAmerican Hospital: Opiates Benzodiazepine Cocaine Barbiturates Propoxyphene PCP Cannabinoids Amphetamine Class Alcohol NOTE: Drug of abuse testing performed by the Hospital Laboratory is for medical purposes only. It is not conducted under legal chain of custody, and should not be used for legal or employment purposes. Positive results are not confirmed by a secondary method. Glucose Tolerance Test (2 hour) The routine tolerance test lasts 2 hours with blood samples being obtained at fasting and 120 minutes after ingestion of 75 grams of glucose following criteria established by the American Diabetes Association. NOTE: Glucose tolerance testing is not recommended on non-ambulatory or acutely ill patients. The American Diabetes Association does not recommend oral glucose tolerance testing for the diagnosis of diabetes mellitus. 1. Be sure the patient fasting (except water) for at least 8 hours. 2. A fasting blood specimen is drawn and labeled following standard health system policy and procedure grams of glucose solution is given to the patient. The glucose solution should be consumed within 5 minutes. 4. The two hour specimen should be drawn two hours after the glucose solution is given. 4

5 Scheduled Draw Times for Therapeutic Drugs DRUGS NOT SPECIFIED ARE TO BE DRAWN PRIOR TO NEXT DOSE Drug Digoxin (Lanoxin) Gentamicin Draw time At least 8 hours after the last dose or immediately prior to the next dose Peak: 30 minutes after a 30 minute infusion or 60 minutes after an IM injection Lithium Theophylline 12 hours after the last dose Slow release: 4 hours after dose Theo-dur: 3-7 hours after dose Tobramycin Peak: 30 minutes after a 30 minute infusion or 60 minutes after an IM injection Valproic acid (Depakene) Peak: 1-3 hours following oral dose Vancomycin Trough: Prior to next dose Peak: 60 minutes after end of infusion or IM injection 5