Should an 80-year-old patient with type 2 diabetes (T2D), congestive heart failure (CHF), and hypertension, admitted for acute hypoxemia and possible aspiration pneumonia, continue oral diabetes medications, repaglinide (generic name) and metformin (generic name), or be switched to insulin therapy while requiring supplemental oxygen?

Management of Diabetes Medications in an 80-Year-Old Patient with Acute Hypoxemia

For an 80-year-old patient with type 2 diabetes admitted for acute hypoxemia and possible aspiration pneumonia requiring 5L of oxygen, oral diabetes medications (repaglinide and metformin) should be discontinued and insulin therapy should be initiated during hospitalization due to the risk of lactic acidosis with metformin in hypoxic states and the unpredictable absorption of oral agents during acute illness. 1

Rationale for Discontinuing Oral Agents

• Metformin should be discontinued in patients with hypoxia due to increased risk of lactic acidosis, which is a contraindication specifically mentioned in guidelines and drug labeling 1, 2
• Metformin is contraindicated in patients with "anaerobic metabolism (i.e., sepsis, hypoxia)" as these conditions increase the risk of lactic acidosis 1
• Repaglinide, as an insulin secretagogue, may cause unpredictable hypoglycemia in acutely ill patients with variable oral intake 1, 3
• The patient's advanced age (80 years) is an additional risk factor that warrants caution with oral agents during acute illness 1

Recommended Insulin Regimen

• For this hospitalized patient with possible aspiration pneumonia and supplemental oxygen requirements, a basal insulin approach is most appropriate 1
• A basal-plus approach is preferred for patients with decreased oral intake and those undergoing acute illness 1
• Starting insulin total daily dose should be reduced to 0.1-0.15 units/kg/day for elderly patients, given mainly as basal insulin 1
• Supplemental (correction) rapid-acting insulin can be added for glucose levels >180 mg/dL before meals or every 6 hours if nil by mouth 1

Avoiding Common Pitfalls

• Avoid sliding scale insulin alone (without basal insulin) as this approach is discouraged and associated with poor glycemic control 1, 4
• Premixed insulin formulations should be avoided in the hospital setting as they have been associated with a threefold higher rate of hypoglycemia in elderly patients compared to basal-bolus regimens 1
• Do not continue metformin even with normal kidney function in this patient due to the hypoxemia, which is a specific contraindication 1, 2
• Target blood glucose of 140-180 mg/dL is appropriate for hospitalized patients, as stricter targets increase hypoglycemia risk without improving outcomes 1, 4

Special Considerations for This Patient

• The patient's multiple comorbidities (CHF, hypertension, T2DM) increase the risk of adverse outcomes from both hyperglycemia and hypoglycemia 1
• Advanced age (80 years) warrants more conservative glycemic targets and careful insulin dosing to avoid hypoglycemia 1
• Acute hypoxemia requiring 5L oxygen is a clear contraindication to metformin due to increased risk of lactic acidosis 1, 2
• Once the patient's condition stabilizes and hypoxemia resolves, reassessment of diabetes regimen should occur before discharge 1

Discharge Planning Considerations

• For patients with HbA1c <7.5-8%, consider returning to pre-hospitalization regimen if no contraindications remain 1
• For patients with HbA1c between 8-10%, consider discharge on oral agents plus basal insulin at 50% of the hospital basal dose 1
• Reassess kidney function before restarting metformin, and ensure resolution of hypoxemia 1, 2
• Provide clear communication of the discharge diabetes regimen to both the patient/caregiver and primary care physician to avoid medication errors 1

By following these evidence-based recommendations, you can optimize glycemic control while minimizing risks in this elderly patient with acute hypoxemia and multiple comorbidities.