New lab-developed procedure improves treatment for fire victims

Researchers at U of A and Alberta Precision Labs develop protocol to alert ER doctors of potential for misdiagnosing patients treated for cyanide poisoning.

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U of A graduate Steven Dang, a medical lab technologist with Alberta Precision Laboratories, shows the difference between normal blood plasma (left) and plasma from a patient treated with hydroxocobalamin for cyanide poisoning (right). (Photo: Alberta Precision Laboratories)

During his fourth year as a medical laboratory science student at the University of Alberta, Steven Dang embarked on a project at the Misericordia Hospital laboratory to help improve treatment of patients rescued from house fires.

Patients who arrive at hospitals from house fires are often treated for cyanide poisoning due to the toxic fumes generated by fires in the home. A major side-effect of treatment with the drug hydroxocobalamin is that patients’ blood plasma and urine turns red, which can interfere with many lab tests—leading to incorrect results that can affect patients’ care and treatment for a wide range of health issues.

Dang and his supervisors, Josh Raizman and Albert Tsui, both clinical biochemists with Alberta Precision Laboratories (APL) and members of the U of A’s Department of Laboratory Medicine and Pathology, developed a new protocol to alert emergency room doctors of the potential for misdiagnosing patients receiving the treatment, helping to ensure correct patient care in these situations.

The protocol is now being used in the Misericordia and University of Alberta hospitals, where patients suffering from smoke inhalation injuries are most commonly treated in Edmonton, and was recently published in the journal Clinical Biochemistry

“This all started when I began my research project at the Misericordia laboratory and my supervisor, Dr. Josh Raizman, gave me a project to characterize the impact of hydroxocobalamin interference in patients’ lab tests and develop a laboratory process to handle and report results,” said Dang.

“Of 77 tests analyzed, 35 per cent of them were compromised. This is when we realized we needed to do more to alert emergency doctors and the lab that if a patient receives this drug, we should not be reporting results on tests that are inaccurate and unreliable,” he added.

Another objective of the study was to identify what other tests might also be affected by the drug and to prevent unreliable results from being released in patients’ medical charts.

For example, the researchers found that hydroxocobalamin had the largest impact on a test of liver function, altering results. If these outcomes are incorrectly reported, the patient could be inaccurately diagnosed with liver failure, which in turn could lead to unnecessary treatment.

The findings reinforce the importance of the laboratory team as an integral part of the health-care team, noted Dang, who is now a medical laboratory technologist with APL.

“Our ER doctors and lab team said they found it to be helpful to have this flagged on a patient’s medical chart, so that test results are interpreted accurately and a proper diagnosis is happening in a timely manner.”

Raizman said one of the unique aspects of the study was taking basic data generated at the laboratory bench and applying it to ultimately improve patient care at the bedside.

“Our multidisciplinary approach involving close collaboration between the laboratory and clinical staff was a key driver that made this project successful,” Raizman said.

With the publication of their protocol, the team is hoping other hospitals across the province, and beyond, will develop similar protocols to improve the diagnosis and treatment of patients.

“It is important to note that this study is only applicable to instruments used in Edmonton, but we believe it will provide valuable information for other sites across the province to conduct similar studies and potentially have this protocol adopted more widely,” Raizman said.

The study was supported in part by a research grant from Covenant Health.