A medical laboratory or clinical laboratory is a laboratory where tests are done on clinical specimens in order to get information about the health of a patient as pertaining to the diagnosis, treatment, and prevention of disease.[1]
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Laboratory medicine is generally divided into two sections, and each of which is further divided into a number of units. These two sections are:
Distribution of clinical laboratories in health institutions varies greatly from one place to another. Take for example microbiology, some health facilities have a single laboratory for microbiology, while others have a separate lab for each unit, with nothing called a "microbiology" lab.
Here's a detailed breakdown of the responsibilities of each unit:
The staff of clinical laboratories may include:
The laboratory management often consists of:
Some of these titles may not exist in some countries or may have different names. In France, clinical biologists may also be Medical director and laboratory manager.
In many countries, there are two main types of labs that process the majority of medical specimens. Hospital laboratories are attached to a hospital, and perform tests on patients. Private (or community) laboratories receive samples from general practitioners, insurance companies, clinical research sites and other health clinics for analysis. These can also be called reference laboratories where more unusual and obscure tests are performed. For extremely specialised tests, samples may go to a research laboratory. A lot of samples are sent between different labs for uncommon tests. It is more cost effective if a particular laboratory specializes in a rare test, receiving specimens (and money) from other labs, while sending away tests it cannot do.
In many countries there are mainly three types of Medical Laboratories as per the types of investigations carried out. 1. Clinical Pathology 2. Clinical Microbiology & 3. Clinical Biochemistry laboratories. 1. Clinical Pathology: Haematology, Histopathology, Cytology, Routine Pathology2. Clinical Microbiology: Bacteriology, Mycobacteriology, Virology, Mycology, Parasitology, Immunology, Serology.3. Clinical Biochemistry: Biochemical analysis, Hormonal assays etc.Blood Banks:- Blood bank is a separate body. Its laboratory need Microbiological analysis for infectious diseases that may be found in blood. Pathology to observe Blood grouping, Haematology & cross matching reactions. It also involves PRO department for the communication & contact for blood donations etc.. Molecular diagnostic lab or cyotgenetics and molecular biology lab is the latest addition to the three types of medical laboratories listed above in many countries.
Sample processing will usually start with a set of samples and a request form.
Typically a set of vacutainer tubes containing blood, or any other specimen, will arrive to the laboratory in a small plastic bag, along with the form.
The form and the specimens are given a laboratory number. The specimens will usually all receive the same number, often as a sticker that can be placed on the tubes and form. This label has a barcode that can be scanned by automated analyzers and test requests uploaded from the LIS. Entry of requests onto a laboratory management system involves typing, or scanning (where barcodes are used) in the laboratory number, and entering the patient identification, as well as any tests requested. This allows laboratory machines, computers and staff to know what tests are pending, and also gives a place (such as a hospital department, doctor or other customer) for results to go.
For biochemistry samples, blood is usually centrifuged and serum is separated. If the serum needs to go on more than one machine, it can be divided into separate tubes.
Many specimens end up in one or more sophisticated automated analysers, that process a fraction of the sample and return one or more "results". Some laboratories use robotic sample handlers (Laboratory automation) to optimize the workflow and reduce contamination risk and sample handling of the staff.
The work flow in a lab is usually heavy from 2:00 am to 10:00 am. Nurses and doctors generally have their patients tested at least once a day with general complete blood counts and chemistry profiles. These orders are then drawn during a morning run by phlebotomists for results to be available in the patient's charts for the attending physicians to consult during their morning rounds. Another busy time for the lab is after 3:00 pm when private practice physician offices are closing. Couriers will pick up specimens that have been drawn throughout the day and deliver them to the lab. Also, couriers will stop at outpatient drawing centers and pick up specimens. These specimens will be processed in the evening and overnight to ensure results will be available the following day.
Laboratories today are held together by a system of software programs and computers that exchange data about patients, test requests, and test results known as a Laboratory information system or LIS. The LIS is interfaced with the hospital information system.
This system enables hospitals and labs to order the correct test requests for each patient, keep track of individual patient or specimen histories, and help guarantee a better quality of results as well as printing hard copies of the results for patient charts and doctors to check.
According to ISO 15189 norm, all pathological results must be verified by a competent professional. In some countries staff like clinical scientists do the majority of this work inside the laboratory with abnormal results referred to the relevant pathologist. In others, only medical staff (pathologist or clinical biologist) is concerned by this phase. It can be assisted by some software in order to validate normal or non modified results. Medical staff are sometimes also required in order to explain pathology results to physicians. For a simple result given by phone or for a technical problem it's a medical technologist or medical lab scientist explaining it to a registered nurse.
Departments in some countries are exclusively directed by a specialized Pathologist, in others a consultant, medical or non-medical, may be the Head of Department. Clinical Scientists have the right to interpret and discuss pathology results in their discipline in many countries, in Europe they are qualified to at least Masters level, may have a PhD and can have an exit qualification equivalent to medical staff e.g. FRCPath in the UK. In France only medical staff (Pharm.D. and M.D. specialized in Anatomical pathology or Clinical biology) can discuss pathological results, clinical scientists are not considered as a part of medical staff.
Credibility of medical laboratories is paramount to the health and safety of the patients relying on the testing services provided by these labs. The international standard in use today for the accreditation of medical laboratories is ISO 15189 - Medical laboratories - particular requirements for quality and competence.
Accreditation is done by the Joint Commission, College of American Pathologists, AABB, and other state and federal agencies. CLIA 88 or the Clinical Laboratory Improvement Amendments also dictate testing and personnel.
The accrediting body in Australia is NATA, all laboratories must be NATA accredited to receive payment from Medicare.
In France, where accrediting body is COFRAC, in 2010, modification of legislation established ISO 15189 accreditation as an obligation for all clinical laboratories.[2]