Key cautions & base contact

This adult/adolescent order is not a pediatric DKA fluid protocol.
Do not treat a normal-looking glucose threshold as a substitute for assessment of breathing or perfusion.

Assess more than the glucose

Measure and document glucose, mental status, vital signs, oxygen saturation, hydration, and associated symptoms. Deep labored breathing may be Kussmaul respirations.
Look for fever/infection, vomiting, abdominal pain, and significant comorbidity. Consider sepsis as a cause or coexisting problem.

At glucose at least 400 mg/dL, the source directs ALS transport.
At glucose above 250 with confusion/lethargy, heart rate above 120, respiratory rate above 20 with labored breathing, fever history, or SpO₂ below 94%, transport ALS and consider DKA.

For the suspected DKA branch, provide oxygen as tolerated, monitor the rhythm, and establish IV access.
Without evidence of fluid overload, give normal saline 250 mL IV and reassess; may repeat to a maximum 1 L for adequate perfusion. Consider ETCO₂ assessment for acidosis. No insulin administration regimen is provided in this field order.

BLS consideration requires normal mental status, vital signs, and pulse oximetry and no other complaint requiring ALS. The source separates glucose below 250 from glucose above 250 but below 400; the latter also requires absence of relevant comorbidity.
Consider ALS with active cancer, renal failure, liver disease, immunosuppression, abdominal pain with vomiting, CHF, organ transplant, or frailty. Do not infer a BLS decision solely from one glucose value or a boundary not explicitly addressed in the source.
Document serial findings and the full rationale for the chosen level of transport.