Stepping Hill murder trial: Insulin 'may not have killed three' claim
A diabetes expert has told a murder trial it was impossible to say that patients allegedly killed by a nurse had died of insulin poisoning.
Victorino Chua, 49, denies murdering three patients at Stepping Hill Hospital, Stockport.
Prof Brian Frier, the first defence witness, told Manchester Crown Court hypoglycaemia or low blood sugar may not have killed the patients.
The jury heard he had written hundreds of publications on the conditions.
Mr Chua, of Heaton Norris, is accused of murdering Tracey Arden, 44, Derek Weaver, 83, and Arnold Lancaster, 71, by poisoning them with insulin.
Prof Frier told the jury that hypoglycaemia may or may not have hastened the deaths of Ms Arden and Mr Weaver.
In the case of Ms Arden, he said going any further would be "entirely speculating."
Asked about Mr Weaver's death, he said: "It's unlikely the hypoglycaemia precipitated his demise".
'A final event'
The defence agree Ms Arden and Mr Weaver were wrongly given insulin but insist the defendant did not administer the hormone.
Prof Frier said Mr Lancaster was "teetering on the edge of hypoglycaemia... at admission."
He added a drop in blood sugar was the result of terminal cancer and septicaemia, adding: "It's a final event in the course of his illness."
The court was told Mr Lancaster's cancer was so advanced his liver was almost completely replaced by tumours.
Prosecution witness Dr Peter Kroker had previously told the jury he believed hypoglycaemia most likely contributed to Ms Arden and Mr Weaver's deaths.
He added it was "more likely than not" the alleged administration of insulin hastened Mr Lancaster's death and it was a "major metabolic attack" on the patient's system.
Mr Chua also denies poisoning another 18 patients using saline solution contaminated with insulin in the summer of 2011 and altering prescription charts on a ward at the hospital in January 2012.
The case continues.