Factors affected the result of a glucometer at high altitude:
(1) altitude and oxygen tension, especially for glucose oxidase methods
(2) low temperature
(3) high humidity
(4) instrument damage/malfunction
According to Bilen et al, glucometers using glucose oxidase tended to report slightly lower values than a reference method, while glucometers using glucose hexokinase reported higher values.
Recommendations:
(1) Investigate the performance of the glucometer before the trip.
(2) Calibrate the instrument frequently (so take extra calibrators).
(3) Protect the glucometer and test strips from moisture and humidity.
(4) Protect the meter from environmental exposures and impacts.
(5) Carry one or more backup meters.
(6) Question results that do not make sense.
(7) There should be one or more companions on the trip who are able to assist the patient.
Differential diagnosis for hypoglycemia:
(1) altitude sickness
