Hi Silke

It is known that potassium results from serum are 0.1 - 0.2 mmol/l higher than plasma results with differences of up to 0.9 mmoL.

Normal concentration of serum potassium at various ages in mmol / L (mEq / L):

Neonates 3.9 - 5.9 ; Lactants 4.0 - 5.3 ; Children 3.5 - 4.7 ; Adolescents and Adults 3.5- 5.1 Reference: Hyman D, Kplan NM, The difference between serum and plasma potassium. N. Engl. J. Med. 1985:313:642. And there is a Nomogram for Stimating Potasium Deficit in Plasma Levels, from ScribnerWashington University School of Medicine. 1960

Alteraciones Electroliticas en Pediatria by Luis Velasquez Jones 1991 Hosp. Inf. Mexico

just as a suggestion, but there is ongoing work on lab reference values in children, so a pubmed search on online search on CALIPER study (canadian study) might be useful. Alternatively, there are reference values in the Pediatrics textbooks ? hope that this helps ?

Silke, Other reference: Article Pediatric reference intervals for general clinical chemistry...

Serum was used in the Swedish study, and lithium-heparin plasma in the Danish investigation. Please do your own research for your country

Plasma potassium level is dependent on acid-base status and correlates well with platelet count. This makes it difficult to define proper reference values. I'd recommend that you check also other electrolytes and blood gas values.If you see acidosis and a high potassium concentration it means that the potassium level will be normalized when the acidosis is corrected.

Dear

Silke (Congrats)

Please, read this mail, and put the reference of this preliminary data, because the CALIPER Study at moment did not have the reference values for K (You can contact with Dr. Khosrow Adeli):

Dear Dr. Sarmiento,

Thank you for your message. We have new potassium data on Radiometer ABL90Flex system. It will be published in the near future. Below is our preliminary data

Potassium

Pediatric Reference Range: 3.6-4.7 mmol/L

(no age or sex differences observed)

Thx

Khosrow Adeli PhD, FCACB, DABCC

Head and Professor, Clinical Biochemistry, Paediatric Laboratory Medicine

Senior Scientist, Molecular Medicine, Research Institute

The Hospital for Sick Children/University of Toronto

555 University Avenue | Toronto, ON, Canada

Phone: (416) 813 8682 | Fax: (416) 813 6257

Email: [email protected]