Urine test came back low potassium and high co2 levels. what could this mean?

See below: You are more likely referring to a BMP blood test (not a urine test) that measures your electrolytes (sodium, potassium, chloride), glucose, kidney function (BUN, creatinine), acid-base status (CO2 or bicarbonate) and calcium level as well. The CO2 is an indirect measure of how well your kidneys and lungs are working. A number of causes of high CO2/low K+, with diuretics being most common cause.