Intralipid and coagulation
Research type
Research Study
Full title
Reviewing the effects of intravenous lipid emulsion administration on the analysis of coagulation blood tests
IRAS ID
265643
Contact name
Elizabeth Bruna
Contact email
Sponsor organisation
Guy's & St Thomas' Foundation NHS Trust
Duration of Study in the UK
0 years, 6 months, 1 days
Research summary
Summary of Research
Intravenous lipid emulsion therapies are used as part of treatment for some types of poisonings, particularly for overdose of local anaesthetics. However, because of the lipid nature of the infusion it can interfere with laboratory analysis of a patient's serum during and immediately after infusion. Previous studies have looked at the degree of interference with several common laboratory tests, but not with respect to parameters of coagulation. Since the lipid emulsion and the overdoses it is given for could potentially affect the ability of the blood to clot, this study aims to determine what the effect of lipid emulsion is on coagulation tests on healthy blood (ie. those assessments of the bloods ability to form clots). We will be taking blood samples from healthy volunteers, and introducing different concentrations of intravenous lipid emulsion to the collected samples to approximate clinically relevant concentrations. We will then perform routine and advanced laboratory tests on the samples to determine the effect of the lipid emulsion on standard and alternative testing methods for coagulation studies.
Summary of Results
Reviewing the effects of intravenous lipid emulsion administration on the analysis of coagulation blood tests The study was carried out by doctors on the clinical toxicology team at Guys and St Thomas’ NHS Foundation Trust, London. There was no external funding and there were no competing conflicts of interests.
Intravenous lipid emulsion (Intralipid®) is a medication that can be used as an antidote for certain poisonings. It contains a high dose of lipid, a certain type and mixture of fat. Previous studies have shown that Intralipid administration can interfere with the results of blood tests. This can make it difficult for doctors who are treating patients with intralipid because blood tests that are used to monitor the patient can be unreliable One group of important blood tests are coagulation (clotting) blood tests which are used to determine how ‘sticky’ the blood is and whether patients may be at risk of bleeding or blood clots. The aim of this study was to find out how much these coagulation (clotting) tests are changed if intralipid is given. We also wanted to see if different laboratory tests could be used for better results.
We would like to thank the 19 study participants who volunteered for our study and donated three 3.5ml blood samples. They were healthy volunteers with no past medical history. The study ran from October to November 2022 at our hospital in London.
After taking the blood samples, we added intralipid in two different concentrations to two of the three collection tubes. The laboratory used three different test methods for clotting. The first test was the routine coagulation (clotting) tests that hospitals use every day on patient samples. The second test was an older test method that needed more manual handling. The third test used the same machine as the first test, but the sample was prepared in a different way to try to remove the intralipid and prevent it from interfering with the coagulation (clotting) tests.
The results of the study confirmed that intralipid interferes with routine coagulation (clotting) tests, particularly at the high dose of intralipid that is often used to treat patients. Using the two alternative testing methods we were able to overcome this problem
It is important that doctors know that Intralipid can change coagulation (clotting) tests. If intralipid is being used to treat a patient and coagulation (clotting) tests need to be carried out, it is important that the doctors/nurses treating the patient inform the laboratory so that the laboratory can change their testing method to ensure that the results of the test are reliable.
REC name
North West - Greater Manchester East Research Ethics Committee
REC reference
19/NW/0734
Date of REC Opinion
11 Dec 2019
REC opinion
Favourable Opinion