Endocrine Abstracts

Background: The insulin stress test (IST) is accepted as the gold standard investigation of the hypothalamio-pituitary–adrenal axis (HPA). The test has been shown to be reliable though potentially unpleasant for the patient and has been associated with complications such as loss of consciousness, seizures, arrythmias, angina, myocardial infarction and death. To this effect close medical supervision is always required when an IST is performed.

Methods: We have audited the number of adverse events for all of the IST’s performed in our tertiary referral centre over a 2 year period. All patients who underwent an IST from October 2007 to October 2009 were included in the analysis. Data was obtained from the central laboratory and from review of patient and nursing notes.

Results: There were a total of 90 patients who had an IST done over the study period. There were 47 patients and 43 males (mean age 42.7 (IQR 35 to 52). A history of ischaemic heart disease, previous seizures and an abnormal ECG were considered absolute contraindications to performing an IST. There were 2 (2.2%) adverse events over the 2 years. One patient developed chest pain and required admission to hospital. The ECG performed prior and after the test was normal. The troponin test was normal and the patient was discharged the day after with a diagnosis of non cardiac chest pain. One other lost consciousness and required third party help for correction of her hypoglycaemia.

Conclusion: Our audit re-highlights the importance of experienced medical supervision when conducting an IST due the potential adverse risks associated with the procedure that can be considered safe in the correct hands.