Clotted blood tube
(Clot activator tube) (in ice bath)
Minimum blood volume: 6 mL
Paediatric clotted blood tube (in ice bath)
Number of vials: 2
Minimum blood volume: 1.6 mL
If the haemoglucostix is < 2.2 mmol/L, take a simultaneous glucose and insulin level.
Send in ice immediately to the laboratory with concurrent plasma glucose. Phone to the laboratory (office hour 2331 / after office hour 3353) before sending the specimen.
Avoid haemolysis, which can lead to spuriously low value.
The presence of circulating anti-insulin antibodies and certain insulin analogues (such as aspart, detemir, glargine, glulisine and lispro) may affect the insulin result.
< 29.1 mIU/L
(Source: from manufacturer's kit insert)
Footnote:
Insulin level depends on various factors including pancreatic reserve,
plasma glucose, state of fasting, etc. Please interpret the insulin with
concurrent plasma glucose.
Investigation of fasting hypoglycaemia and insulin resistant states
Increased levels and increased insulin / glucose ratios are found with pancreatic islet beta cell hyperplasia or insulinomas.
Non-insulin dependent diabetes mellitus and insulin therapy may also give high levels.
To identify self-administration of insulin as a cause of hypoglycaemia, C-peptide assay is also required.