STORY BYWhen they are not ripping clothes off each other, the docs on Grey’s Anatomy rip out orders for lab tests like auctioneers on Red Bull.
“OK, we’ve got a GSW, get me film, a CBC, Chem7, UA and a CT, Stat!”
Translation: a gun shot wound victim who needs an x-ray, blood work, urinalysis, computerized tomography imaging, a shout-out to kidney function and a bunch of other stuff...really fast (because it sounds really cool to say “stat”).
If you’re like the other viewers at home about to tune in to this season’s dose of medical dramas, the orders rattled off by Doctor McDreamy and his colleagues sound as random as letters in alphabet soup. But deciphering the code can help you better understand what is going on the next time your doctor orders up “a little lab work.”
Whether you seek medical care at the ER or a clinic, for an accident or the flu, chances are you will undergo two tests: a Complete Blood Count (CBC) and a Urinalysis (UA). These two simple tests provide many answers to what is going on in the body.
Considered the workhorse of lab tests, the CBC measures
“The CBC gives a snapshot of the patient’s overall health,” says Elizabeth Fuselier, Doctor of Nursing Practice. “This test helps health care professionals evaluate symptoms like weakness, bruising, anemia, fatigue, fever, presence of infection and muscle aches to determine what is causing those symptoms so that we can make a diagnosis.”
The CBC is used to diagnose and manage many diseases. The results can tell health professionals if a patient has problems with dehydration or loss of blood. The CBC also shows abnormalities in the production, life span and rate that blood cells are destroyed. It also indicates the presence of infection, allergies or problems with clotting.
Such a simple test can provide revealing and sometimes surprising information about the human body.
“I had this one patient, an otherwise healthy young man, who couldn’t shake this cold,” says Elda Ramirez, associate professor of nursing at the UT School of Nursing and a nurse practitioner. “His doctor had put him on antibiotics and he wasn’t getting any better, which was a warning sign. We ordered a CBC to see what we could find. His white blood cell count came back at over 100,000 (normal is around 4500 to 10,000 cells per microliter of blood). We thought we made a mistake and reran the test. The results were the same. He had leukemia. The results were a total surprise for him and for us.”
In CBC test results, normal values for a red blood count (RBC) should range between
Normal range for a white blood count (WBC)
Normal platelet (thrombocyte) count range
Normal hematocrit values should range
Hemoglobin should range
Three measurements reflect the size and hemoglobin concentration of individual cells and are used to diagnose types of anemia:
MCV, Mean Corpuscular Volume
MCH, Mean Corpuscular Hemoglobin
MCHC Mean Corpuscular Hemoglobin Concentration
Next to blood, it is urine and its analysis that provides vital clues about the health problems of a patient. In her more than 15 years spent nursing in emergency rooms across the city, Ramirez has come to depend on the UA and the urine sample itself for answers.
“I guarantee you, most physicians, nurses and technicians have a good idea what is wrong with a patient just by looking at their urine sample and from the odor and color of their urine,” Ramirez says.
Today’s nursing and medical students get off easy with just a sight test of a urine sample. In past generations, health care practitioners were encouraged to smell and taste the urine sample. Thankfully, urinalysis now makes the taste test obsolete.
“The actual breakdown of the urine is going to tell you the pH of the urine, what’s inside the urine, whether there any white blood cells (sign of infection) in it and whether there is glucose in it, which is a sign of diabetes,” Ramirez says.
A urinalysis also tests for urine specific gravity, which shows how concentrated or diluted the urine is.
If you are a woman, you will also likely receive a pregnancy test, whether you believe you are pregnant or not.
“What I was taught early, bottom line, is that if patients are fertile, they get a pregnancy test,” Ramirez says. “The only time you don’t do a pregnancy test is if they have hit menopause. It is one of those things you never want to miss in a female.”
Just as not all people are alike, neither are lab tests. Each hospital uses its own parameters to judge test results, and lab equipment may be newer and more sensitive at some hospitals than others. And, just as in cake baking, even altitude can affect certain lab results.
Tests results also vary from person to person. A “normal” test result in one patient may be abnormal in another. For example, normal potassium levels for a person with end-stage kidney disease may be 5 (normal ranges from 3.5 to 4.5), because the patient can’t urinate and expel potassium from his or her body.
Confusing the issue even further, normal is a matter of degrees. Normal test results are separated into low normal, normal and high normal. For example, normal sodium levels range between 135 and 145. A value of 136 may be considered high normal. High or low normal values sometimes indicate a trend, and need to be closely monitored.
When understood in the correct context, lab values provide important information about your health. “All patients should understand what they are for, especially patients with chronic disorders, such as diabetes, and parents of children with chronic disorders,” Ramirez says. “I don’t want them to become lab technicians, but keeping track of certain lab results is important in terms of their health care or the health care of their children.”
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Elizabeth Fuselier is a Doctor of Nursing Practice.
Elda Ramirez is an associate professor of nursing at the UT School of Nursing and a nurse practitioner.
Packing Bag Lunches Safely
If you pack lunches for your child to take to school, be careful that you do not accidentally expose them to foodborne illness.
Bagged lunches, especially those containing perishable foods, need to be packed and handled properly in order to keep the food safe. In general, perishable foods should not be left at room temperature for more than two hours. If left out too long, the temperature of the food can enter the danger zone where bacteria grow most rapidly, which is between 40 and 140 degrees Fahrenheit.
Below are some tips to help families pack bagged lunches safely:
Before eating lunch or snacks at school, make sure your child washes his or her hands with soap and warm water for at least 20 seconds. If your child's school does not have a handwashing program in place, encourage them to adopt a such a program, as handwashing is one of the best ways kids and parents can protect health and stop the spread of germs.
