Module 2: MLT Review Questions

the chain of infection describes how microorganisms are spread. There are six components or links in this chain. They include infectious agent, reservoir, exit pathway, transmission method, entry path and susceptible host. If any link is missing, infection is stopped. One of the most effective ways to break the chain of infection is hand washing.

Under Universal Precautions blood and certain body fluids from all individuals are considered potentially hazardous. Any body fluids with visible blood should be considered potentially hazardous and all appropriate PPE should be worn.

Since a specimen can contain blood that is not visible, the body substance isolation was added as a modification to Universal Precautions. Under BSI all body fluids must be considered potentially infectious and proper PPE should be worn.

Since a specimen can contain blood that is not visible, the body substance isolation was added as a modification to Universal Precautions. Under BSI all body fluids must be considered potentially infectious and proper PPE should be worn.

Lab coats should provide as much coverage as possible. This is accomplished by keeping the coat buttoned and having long sleeves. The coat fit well to prevent excess from catching in laboratory equipment. Lab coats should only be worn in the laboratory and not during breaks or meetings. Many facilities also require a different coat for patient care areas.

All critical results need to be reported to the health care provider. This should be done according to the facilities procedure. This most often requires a call to the provider or the nurse working with the provider. In some cases in the laboratory a procedure will also require that a critical result be repeated to ensure that erroneous results are not reported. In the case of a erroneous result documentation of the correction of that result is required to ensure appropriate patient treatment.

Precision is the ability to be able to obtain the same result multiple times. This would be like hitting the same spot on a target multiple times but not necessary the bulls eye. Accuracy however is the ability to obtain the true result or hit the bull's eye. It is possible to have precision but still not be accurate.

The highest acceptable range for confidence limits is plus or minus 3SD. With this confidence limit it would be expected the 99.7 percent of values should be within range. Many labs do however use plus or minus 2SD. In this case only 95.5 percent of values should be expected to within range. This will mean that 1 out of 20 acceptable control results will be outside of range and will need to be reran. The smaller range helps to detect problems earlier and prevent patient errors.

Education, training and competency are all required to be documented for employees. Proficiency testing is unknown samples a laboratory receives from an outside agency to help access the accuracy of the laboratory. Although all employees that perform testing should also participate in proficiency testing, it not required documentation for all employees.