Learning Objectives
1. Explain the purpose of monitoring a client’s fluid intake and output (I&O). Describe and demonstrate how to keep accurate I&O records.
2. Demonstrate correct measurement of urine volume.
3. Describe what is meant by urine specific gravity, listing one medical condition associated with high specific gravity; one related to low specific gravity.
4. Identify at least three reasons for laboratory examination of urine.
5. Describe and demonstrate correct collection of the following urine specimens: midstream, 24-hour, fractional, and from an indwelling urinary catheter.
6. Identify and explain at least one reason for collecting specimens of stool and sputum.
7. Demonstrate correct collection of a stool specimen. Demonstrate correct collection of a sputum specimen.
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IMPORTANT TERMINOLOGY |
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expectorate |
hydrometer |
urinalysis |
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guaiac |
occult |
urinometer |
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Hematest |
residual urine |
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Hemoccult |
specific gravity |
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Acronyms |
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C&S |
NG |
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IV |
O&P |
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mL |
TPN |
One means by which healthcare providers and other members of the team learn information about the health status of clients is by collecting samples of body fluids for laboratory study. Nurses are often responsible for collecting specimens of urine, stool, sputum, and blood. The nurse may measure or observe such specimens for characteristics or send them to the laboratory for examination. Be aware of the specific agency protocols for specimen collection. Observing these protocols provides quality control and keeps specimens free from contamination, which is essential in ensuring accuracy and consistency in test results. In Practice: Nursing Care Guidelines 52-1 highlights key information when collecting any specimen.
Nursing Alert Always wear clean gloves when collecting specimens of urine, stool, sputum, wound drainage, or blood. Thorough and consistent handwashing before and after any contact with clients and their specimens limits spread of microorganisms that cause disease. It also helps to protect the specimen from inadvertent contamination by the nurse’s hands.
THE URINE SPECIMEN
As the body’s liquid waste product, urine has typical physical and microscopic characteristics that are excellent indicators of a person’s state of health.Collecting and examining urine can provide significant information. Examples include diagnosis of disorders and monitoring of the client’s recovery or decline, assessment of kidney and/or liver status, presence of legal and illegal drugs, pregnancy, and identification of specific disease-causing organisms.
Keeping Intake and Output Records
The amount of fluids a client consumes and eliminates during a given period is an indicator of his or her nutritional and fluid balance. Over 24 hours, a person’s normal fluid intake and urinary output (I&O: intake & output) will be approximately the same, or balanced. Fluid I&O that is significantly out of balance because of illness may lead to a life-threatening condition. The client may be retaining fluid, have edema, or may be dehydrated. Records of the client’s I&O help guide the provider’s decision-making about increasing or restricting fluids or foods. These records can also be used to assess the effectiveness of certain medications, as well as to establish the client’s elimination patterns. I&O records may be kept for every shift and then totaled for a 24-hour period at midnight. On the electronic record, fluid totals are usually recorded at the end of each shift and totaled automatically by the computer.
IN PRACTICE: NURSING CARE GUIDELINES 52-1
COLLECTING SPECIMENS AND SAMPLES
• Label specimen containers, including the lids, with the client’s name and other data before collecting the specimen.
• Always wash your hands before and after collecting the specimen
• Always observe Standard Precautions when collecting specimens. Wearing gloves is always necessary for specimen collection.
• The need for masking and wearing eye protection should be anticipated in some cases, such as sputum collection. (In some facilities, eye protection is worn when transferring a urine specimen from a bedpan, hat, or urinal into a graduate or a specimen container.)
• Collect the sample according to the individual facility’s policy and procedure.
• Clean the area involved for sample collection.
• Observe sterile technique for sample collection, even though the specimen is not always sterile.
• Place all specimens in biohazard bags to protect staff and other clients.
• Transport the specimen to the laboratory immediately
• Be sure the appropriate laboratory request forms accompany the specimen to the laboratory, or the computer order is appropriately entered.
• Record the collection and forwarding of the sample to the laboratory on the client’s health record.
• Check the client’s record later to determine if the results need to be brought to the attention of the primary healthcare provider immediately
To measure total food and fluid intake, the order is given to “record food and fluid intake” or “I&O + calorie count.” In this case, record exactly what the client ate, directly on the client menu, or as per agency protocol. Record fluids on the I&O sheet or computer. Each nurse is responsible for recording I&O as it is measured. Two records may be kept—a temporary worksheet at the bedside records I&O for each shift; this information is transferred to the 24-hour totals in the permanent record. Figure 52-1 shows a sample paper I&O record of the type that would be kept at the bedside. The electronic format often looks similar. Amounts recorded for I&O are measured in milliliters (mL). (The term cc [cubic centimeter] is rarely used today; 1 cc equals approximately 1 mL.)
Key Concept Some normal situations can cause fluid intake and output to be quite different. For example, during very hot weather, fluid is lost through perspiration, but it cannot be measured. Eating extra salt may cause a temporary retention of water in the tissues.
Remember that fluid intake includes items such as gelatin, ice, popsicles, sherbet, thin cereal, broth, tube feedings, and IV fluids. Output includes vomitus, bleeding, chest tube and other drainage, thoracentesis, paracentesis, and nasogastric suction, as well as urine.
Measuring Fluid Intake
Fluid intake includes all fluids consumed through the gastrointestinal (GI) system (by mouth or tube feeding) and fluids taken as part of intravenous (IV) therapy or total parenteral nutrition (TPN). When a client is on I&O, all fluid intake should be measured. Items such as ice, gelatin, ice cream, ice pops, and thin cereal are all considered liquid intake, as are fluids. Each healthcare agency has a list describing the quantity of liquid found in various containers. Use these standard quantities when recording I&O. Record all fluid the client takes in. Count ice as 50% water (e.g., 200 mL of ice would count as 100 mL of fluid intake).
If the client drinks from an unusual container, determine the volume by filling the same container with water. Then, pour the water into a measuring graduate and identify the volume.
Be sure to find out your facility’s policy concerning the recording of water intake from the bedside water pitcher. In some agencies, it is recorded when the pitcher is filled and in others, when it is empty. Do not fill a pitcher or empty one unless you are sure of the procedure.
If the fluid content of solid foods is also being calculated, this will be done by the dietary department.
Measuring Output
Fluid output includes all fluids excreted from the body by any means. Output includes wound drainage, emesis (vomiting), bleeding, watery diarrhea, and nasogastric (NG) suction tube returns. When recording output other than urine, be sure to identify what the output was (e.g., NG drainage, watery stool). Wound drainage on dressings is measured by weighing the dressing after it is removed and comparing it with the dry weight of an identical dressing. Weights are done in milligrams and compared with a standardized chart to convert to milliliters.
Figure 52-2 shows a device called a specimen hat, urinary hat, toilet hat, or half-pan. This device can be placed under the toilet seat to collect either urine or stool without mixing them. (The receptacle is positioned to the front to collect urine and to the back to collect stool.) It has graduated volume marks on the inside to facilitate the approximate measurement of urine. If a more exact measurement is needed, the measuring graduate is used. In Practice: Nursing Procedure 52-1 reviews how to measure urine volume.
Nursing Alert Before giving fluids to a client,find out if the client is on I&O. Do not fill a water pitcher or empty one unless you are sure of the procedure used for recording I&O in your facility
Do not empty a bedpan or urinal without first finding out if the client’s I&O is being recorded or if a urine specimen is required.
Enlist the aid of the client or family when possible, to assist with tracking intake and output and reporting when the water pitcher is empty or when the client has voided (urinated).
FIGURE 52-1 · Example of a paper intake and output (I&O) form used at the bedside. The computerized version is similar, except that the computer calculates the totals and transfers them to the appropriate flowsheet. (Amount of incontinent urine has not been calculated.) D5W means "5% dextrose in water;” as an intravenous (IV) solution.
FIGURE 52-2 · Specimen hat (half-pan) is used to obtain an approximate measure of urine volume. A new hat can be used to collect a clean voided urine specimen or stool specimen. For a urine specimen, the hat is placed with the closed area (receptacle) toward the front of the toilet. For a stool specimen, the closed area is placed toward the rear of the toilet.
Key Concept The urinary output of an infant or incontinent adult can be determined in several ways:
• A special specimen collection bag can be used.These are also available for adults, but are rarely used.
• The infant diaper Depend-type adult diaper, or sanitary napkin can be weighed and compared with the weight of the same item when dry The weight can then be converted, using a chart, to urine volume. (One fluid ounce equals approximately 30 mL.)Urine specimens can be collected in the same manner
Maintaining the IV Fluids Record
Many facilities have a separate I&O record for IV fluids. This record notes specific types of IV fluids, additives, amount of IV fluids absorbed, and amount remaining per shift. Make sure that all IV fluids are included in the 24-hour total.
Measuring Urine Specific Gravity
The urine specific gravity is an indicator of the concentration of urine as compared with pure water. In nearly all cases, laboratory personnel measure the specific gravity of urine during routine urinalysis. However, a nurse may be required to perform this procedure if it is needed frequently or when working in home care or a healthcare clinic. If you have questions, consult the procedure manual of your facility or agency.
Urine specific gravity is measured with a specialized instrument called a urinometer or hydrometer. Measure the reading in decimal increments above 1.000, which is the reading for pure water. Because the increments are in thousandths, be very accurate. The normal range of urine specific gravity is from 1.010 (dilute) to 1.025 (highly concentrated). Test urine as soon as possible after obtaining it to avoid inaccurate results. In Practice: Nursing Procedure 52-2 outlines the steps of measuring the specific gravity of urine.
Extremely concentrated urine (high urine specific gravity, approximately 1.025) may indicate dehydration or fluid retention in the tissues (edema). Low specific gravity (below 1.010) may indicate a disorder, such as diabetes insipidus, or excessive use of diuretic medications. A kidney disorder may cause either a high or low urine specific gravity.
Collecting Urine Specimens for Examination
Urine specimens may be collected and sent to the laboratory for examination. Urinalysis, in which the components of urine are identified, is usually done on all clients at the beginning of treatment and as needed during an illness. In addition, urine is commonly collected to determine the presence of legal or illegal drugs, to determine pregnancy, and to assess for the presence of infection. Many other tests can be performed with urine samples, and some urine tests are significant in the diagnosis of physical disorders. In Practice: Nursing Care Guidelines 52-2 highlights important components of collecting urine specimens.
IN PRACTICE: NURSING CARE GUIDELINES 52-2
COLLECTING URINE SPECIMENS
• Be aware that the amount and content of a urine specimen varies with the time of day and with food and fluid intake. The provider may ask for specimens at different times of the day The urine specimen collected for part of a day is called the single fractional specimen.
• Label specimen bottles before the client voids. Use a waterproof label. Rationale: Doing so reduces handling after the bottle is contaminated and helps the label to adhere to the container better.
• If a waterproof label is not available, check the specimen after the client has voided, to make sure the label is still readable. If this is not the case, dry the outside of the bottle completely and apply a duplicate label. Include the client’s room or department and the provider’s name. In some cases, the time of collection is also necessary. Rationale: Proper labeling prevents errors. The label must be readable for the laboratory to do the test.
• Wake a client in the morning to obtain a routine specimen. Rationale: If all specimens are collected at the same time, the laboratory can establish a baseline. Also, this voided specimen usually represents urine that was collecting in the bladder all night—usually the longest period the client goes without voiding.
• Note on the specimen label if the female client is menstruating at that time. Rationale: One of the tests routinely performed is a test for blood in the urine. If a woman is menstruating at the time a urine specimen is taken, a false-positive reading for blood in the urine will be obtained.
• To avoid contamination and the necessity of collecting another specimen, encourage the client to wash his or her hands before and after collecting the urine specimen. Rationale: It is important not to contaminate the specimen and to protect the client.
• The client should wash the genital area with soap and water immediately before the collection of the specimen. (Single, prepackaged wipes are available for this purpose.) Instruct the female to wipe from front to back, the male to use new wipe on tip of penis. Rationale: It is important that the specimen be from the bladder and not be contaminated from external sources.
• The nurse may need to assist the client in cleansing the perineum and obtaining the urine specimen. Rationale: Some clients may be physically unable to cleanse the perineum adequately, because of serious illness, sedation, or conditions such as arthritis, Huntington’s disease, obesity, or Parkinsonism. In addition, the client may be confused or a child and not able to understand the instructions.
• Use a clean specimen hat or half-pan in the toilet if the female client is ambulatory Place the rounded end toward the front of the toilet, with the open end toward the back. Rationale: Placing the toilet hat in this manner allows the client to have a bowel movement while collecting only urine.
• If the woman is confined to bed, use a clean bedpan. Ask the client to try not to have a bowel movement when using the bedpan. Rationale: Feces would contaminate the specimen.
• Give the male client a urinal to collect the urine specimen. He can use the toilet hat if he will also have a bowel movement. Rationale: Most men are able to void comfortably into the urinal. Using the toilet hat will separate urine from feces.
• If a sterile container is being used to collect the specimen, tell the client not to touch the inside of the container or its cover The insides are considered sterile. If the specimen is to be used for culture and sensitivity this is particularly important. Rationale: Maintaining the sterility of the container helps to ensure accurate results and prevents cross-contamination.
• Maintain Standard Precautions when collecting all types of urine specimens. Rationale: Standard Precautions reduce the risk of infection transmission.
• To pour urine into the specimen container, hold the specimen hat or urinal over the toilet and fill the specimen container about 3/4 full with urine. Be careful not to spill on the outside of the container or on your clean gloved hand. Rationale: This amount of urine will be enough to complete most laboratory tests. If more urine is needed, the laboratory should notify you in advance. Keeping the outside of the container and your gloves dry preserves the label and reduces contamination.
NURSING CARE GUIDELINES 52-2 continued
When pouring a specimen from a bedpan or specimen hat into the specimen container, hold the specimen cup over the toilet.
• All specimens are placed in biohazard bags for transport to the laboratory The outside of the bag is kept clean by using the clean gloved hand only The contaminated hand touches only the specimen container and the inside of the bag. Rationale: This prevents the sample from becoming contaminated and protects you and other healthcare workers.
All specimens are considered to be biohazardous materials and are placed in a specially marked biohazard bag for transport to the laboratory. Touch the outside of the bag only with the clean glove. Touch the specimen container and the inside of the bag only with the contaminated glove.
• Wash your hands before and after the procedure and instruct the client to do the same. Rationale: Handwashing helps prevent infection transmission.
• Document the procedure in the designated place to avoid duplication. Rationale: Documentation provides communication and continuity of care.
Nursing Alert Place all specimens in prescribed leak-proof containers. Keep the outside of these containers clean and dry Place them into plastic biohazard bags for transport to the laboratory Label containers before use; if the container is wet, it will be difficult to label. In some facilities, you must also label the cover of the container and the biohazard bag. Be sure to include the appropriate laboratory request form or make sure the information is correctly programmed into the computer, so the laboratory staff knows which tests to complete.
