Trust missed insulin dose, leading to diabetic ketoacidosis and heart attack

Organisation we investigated: Great Western Hospitals NHS Foundation Trust

Date investigation closed: 15 July 2019

The complaint

Ms B complained about the care the Trust provided to her mother, Mrs H. Ms B said that the Trust failed to provide Mrs H’s overnight insulin dose. This led to Mrs H suffering diabetic ketoacidosis (DKA), which the Trust did not identify or treat in a timely manner. Ms B told us that they believe that Mrs H died of complications caused by DKA.

What we found

The Trust did not give Mrs H its long-acting insulin dose and this led to her suffering from DKA. The Trust said that the handover sheet from one team to the other did not indicate that Mrs H was on insulin and this was why she did not receive the necessary dose. 

Two days after the missed dose, there was a medical review in the morning that raised concerns about Mrs H’s rising blood sugar levels. Four hours later, staff called the emergency team because Mrs H’s condition had deteriorated. The Trust provided treatment for DKA and it appeared that this had resolved by the afternoon, as Mrs H’s blood sugar levels reduced. We therefore found that the Trust correctly treated Mrs H’s DKA.

The Trust accepted that it missed the insulin dose, but it said it correctly treated the DKA. Mrs H had a heart attack and the Trust said that this was unrelated to DKA and the missed insulin dose. We found that the stress caused by DKA would have increased the risk of a heart attack, especially because Mrs H had existing heart disease. It was more likely than not that Mrs H’s DKA contributed to their cardiac event and subsequent death.

It was not possible for us to say with any certainty that Mrs H would not have had a heart attack even if she had received the missed insulin dose. However, it is more likely than not that the DKA contributed to her having a heart attack. The Trust had not acknowledged this.

The Trust should have recorded this as a Serious Incident, as all cases of hospital‑ acquired DKA should be recorded as a Serious Incident. A root cause analysis should be carried out to investigate why a patient has developed DKA.


Mrs H was admitted to the Trust after a fall. She had a history of diabetes and heart disease, as well as a new diagnosis of Parkinson’s disease. During this admission, Mrs H did not receive their night-time insulin injection. Two days later Mrs H developed DKA, a life-threatening complication, and the Trust provided treatment for this. It appeared that the DKA responded to treatment, but Mrs H deteriorated further. Mrs H died two days later from heart failure.

Putting it right

We recommended that the Trust acknowledge it made mistakes and apologise to Ms B for the failings identified and the distress and upset caused to the family. We also recommended that the Trust should prepare an action plan setting out what actions it will take to address the failings we identified.

The Trust complied with our recommendations.

This case summary is featured in the Ombudsman's Casework Report 2019.