Missed Test Results in Hospitalised Patients

Case history

Thursday, 27 December 2012

Dr Peter Domachuk, 33 years of age, presented to the Emergency Department (ED) in the evening complaining of left knee and ankle pain, abdominal pain, nausea and vomiting. He had been taking NSAIDs for the joint pain. His past history included type II diabetes for which he was taking metformin. On examination, his pulse was 116/min and BP 97/61.

There was a left knee effusion. Blood tests revealed Hb 185, WCC 13.9, Na 129, K+ 4.8, lactate 4.01, urea 20.3 and creatinine 194. An ultrasound of the kidneys and renal tract revealed no abnormality. A provisional diagnosis of gastritis was made secondary to NSAIDs. The possibility of gout or rheumatoid arthritis was also considered. The patient was admitted to the ward with a management plan of IV fluids, a protein pump inhibitor and cessation of NSAIDs.

Friday, 28 December 2012

The patient was seen by the physician, medical registrar and RMO on their ward round at about 2.30pm. At this time, the registrar considered the possibility of Addison's disease and instructed the RMO to order an early morning cortisol test. No notation was made in the medical records that the test had been ordered.

In the registrar’s handover notes to the weekend registrar, no mention was made of Addison's disease as a differential diagnosis; however a note was made that if the joint pain persisted and there was decreased mobility the following day, prednisone 50 mg for three days should be prescribed.

Saturday, 29 December 2012

The cortisol test was performed. At noon, Dr Domachuk was seen by the weekend registrar. Repeat blood tests had revealed an improvement in his renal function, consistent with improving hydration. His pain was decreasing. Although the registrar was aware of the plan to prescribe prednisone 50 mg, she considered this too high a dose in a person with diabetes and reduced the dose to 5 mg daily. He was discharged home that afternoon.

Sometime the next evening or following day, Dr Domachuk died at home. The death was reported to the coroner.

Medico-legal issues

An autopsy was performed on 5 January 2013 which revealed coronary artery disease. At this time, the forensic pathologist was not aware of the low serum cortisol result. A cardiology expert reviewed the post-mortem report and opined that the acute cause of death was most likely due to cardiac arrhythmia secondary to coronary artery disease.

Subsequently, the patient's family became aware of the results of the cortisol test and these results were forwarded to the forensic pathologist. With this information and the histological changes observed in the adrenal glands at autopsy, the pathologist concluded that the patient had Addison's disease. She could not determine whether the Addison's disease or coronary artery disease was the primary cause of death, but she was of the opinion that both conditions had played a part.

The coroner was critical that there was no documentation about adrenal insufficiency being considered as a possible differential diagnosis. She noted this was not documented in the progress notes or the registrar's handover documents. Nor was the fact that the cortisol test had been ordered or performed recorded in the notes.

The coroner also found it was unlikely that the patient was informed that a blood test had been performed to investigate the possibility of adrenal insufficiency. It was also noted that low cortisol results were not included in the critical result notification list for the pathology laboratory, where the requesting clinician was contacted by the laboratory with the results.

The coroner’s recommendations included that:

• the Ministry of Health consider publishing a Patient Safety Watch to Local Health Districts with the aim of increasing awareness of the potentially catastrophic outcome of undiagnosed adrenal insufficiency/Addison's disease
• the Ministry of Health Chemical Pathology, Chemical Stream, continue with the proposed implementation of a state-wide critical result notification policy and the development of a state-wide guideline for notifiable thresholds for all critical results, including cortisol.

Risk management strategies

In this case, there were a number of opportunities where the outcome could have been averted:

• recording differential diagnoses and investigations ordered in the medical records
• handover between team members
• informing the patient of differential diagnoses
• follow-up of outstanding test results
• notification of critical results by the laboratory.

Dr Sara Bird
Manager, Medico-legal and Advisory Services
MDA National

Reference

1. Coroners Court of New South Wales. Inquest into the Death of Dr Peter Domachuk, Coroner’s Court, Glebe, 2 December 2015.