Critical results for community based patients and audit of a two tier biochemical phone list

Jeffrey Barron1,2,*, Geoff Smith3

1South West Thames Renal Research Institute, Carshalton, United Kingdom, 2Biochemistry, Labtests, Auckland, 3Biochemistry, Southern Community Laboratories, Dunedin, New Zealand

Introduction: Contacting a requestor with a critical value for a community patient out of hours can be difficult and may require substantial staff resource. We describe the generation and subsequent audit of a two tier phone list that distinguishes between critical values and non-emergency abnormal results, on which action would be appropriate the next day.

Objectives: To reduce phoning critical values to requestors out of office hours.

Methods: The two-tier critical list was formulated after review of the literature on critical values and consultation with local clinical groups. The audit period was 2 months to allow generation of sufficient data.

Results: A two tier critical list was established which differentiates critical results from abnormal.  It uses clinical state, patient age, delta values and algorithms for the reflex addition of tests to differentiate critical from abnormal. The rationale for the selection of specific critical values is discussed.Over the 2 month period of the audit there were 641900 test requests (approximately 11000  daily) with 1814 results on the phone list (approximately 30 daily), of which 31% (557) were classified as critical and 69% as abnormal. This was achieved using algorithms and delta checks. The most frequent analytes on the list were creatinine 59%, troponin 12%, neonatal bilirubin 9%, glucose 4%, CRP 4%, sodium 3%, potassium 2% and ALT 2%. The most frequent critical values were troponin 40%, neonatal bilirubin 27%, CRP 10%, sodium 8%, potassium 6%, glucose 5% and ALT in pregnancy 5%. The number of tests on the critical list was reduced by 69% with an average of 4 phone calls and 1 hour of scientist’s time per night.

Conclusion: The requirements for a critical values list for a community pathology practice are different to those for an acute hospital laboratory. The two tier phone list enhanced identification of critical values, avoided disturbing requestors out of hours with non-emergency abnormal results and saved staff resources

Keywords: Biochemistry, IT-oriented, Laboratory organization