A Simple Solution? The challenges of accurately preparing St Mark's oral rehydration solution on the ward.
by Margaret Collins
Poster Download
Background
St Mark's oral rehydration solution (ORS) is used
in patients with high output ileostomy to reduce stoma output and maintain hydration. St Mark’s ORS recipe is intended to produce a drink with a sodium concentration of 90 mmol/L. The amount of each dry ingredient is given in spoon measurements.
Method
A study was created to determine the accuracy of using a 2.5/5 ml measuring spoon to make St Mark’s ORS. 29 staff members participated 12 of whom completed a questionnaire to investigate their experience in using St Mark’s ORS. Participants measured sodium chloride, sodium bicarbonate and glucose powder using a 5ml/2.5ml medicine spoon. Each measured amount was weighed on electronic scales and recorded in grams.The potential sodium concentration in mmol was calculated.
Results
- Results demonstrate a varied understanding of the rationale for St Mark’s ORS.
- Concern about accuracy when making St Mark’s ORS and difficulty of adapting 1000 ml recipe for a 750 ml jug was observed.
- Using a measuring spoon produced a drink with a mean sodium concentration level of 146 mmol/L, far greater than the desired 90 mmol/L.
Conclusion
St Mark’s ORS made with a measuring spoon will not be a hypotonic drink. The excessive sodium concentration will adversely affect electrolyte balance in patients at high risk of acute kidney injury. Variation in sodium concentration will affect palatability and patient compliance extending reliance on intravenous fluids and lengthening inpatient stay.