Inpatient Insulin Management on the Wards Kevin Bechler, MD Clinical Assistant Professor of Medicine Keck School of Medicine of USC LAC+USC Medical Center

Objectives Know target inpatient glucose values Know the insulin types available at LAC/USC Develop a weight based insulin regimen and know how to make adjustments Manage insulin in patient’s with atypical PO intake

Goal Why do we care? FS Goal: 140-180 Why not more aggressive? Effects on immune function/ wound healing, osmotic diuresis, inflammation/oxidative stress FS Goal: 140-180 Why not more aggressive? NICE SUGAR Trial Hypoglycemia symptoms

Diabetes Medications In general stop PO DM meds Metformin- risk of lactic acidosis, especially with renal/hemodynamic impairment Sulfonylureas- unreliable absorption, risk of severe/prolonged hypoglycemia Others simply not studied well or exert effect mainly post-prandially (GLP-1 agonists, DPP-4 inhibitors) or risk dehydration/GU infections (SGLT 2 inhibitors)

Insulin types at LAC/USC Onset Peak Duration Glargine 1h None 24h NPH 1-2h 4-8h 8-12h Regular 30 min 2h 4-6h Humalog 15 min 2-4h Premixed combo: 70/30: 70% NPH with 30% Regular

What is their the FS? Below or at goal (<140-180): observe Slightly above goal: single dose long acting vs weight based Significantly above goal: weight based Avoid sliding scale to “evaluate requirements”

Insulin Regimen Options Basal/bolus options: NPH/Regular: given together before breakfast and dinner Glargine/Humalog: Humalog given before each meal and glargine before bed Sliding scale is not the answer Worse glycemic control and increased complications compared with basal/bolus Reactive vs proactive

Deal with the Home Regimen What to do with patient’s home insulin regimen Continue Reduce by 25-50% due to difference in food and PO intake Start from scratch with new weight based Controlled on PO meds D/c PO meds, start weight based insulin On no meds but hyperglycemic on admission Weight based, check A1C

Weight based Weight based regimen: Calculate total daily dose of insulin Weight in Kg X correction factor Correction Factor: 0.3-1 based on insulin sensitivity/resistance 0.3 for elderly, slightly above goal, renal disease 0.5 good starting point for most 0.8-1 significant insulin resistance, high dose insulin at home

Weight based Decide on type of insulin No significant difference between Glargine/Humalog vs NPH/Regular Glargine/Humalog- mimics physiology but 4 injections per day NPH/Regular- 2 injections per day Avoid 70/30 as inpatient, increased hypoglycemia

Glargine/Humalog Total insulin dose split in half between 2 types Glargine to be given before bed Humalog component split into thirds to be given before meals

Practice 65 yo man with DM2 on insulin at home (forgot regimen) admitted for DM foot ulcer. Weighs 72kg and initial FS 300.

Practice 85 yo man with DM2 and CKD2 on oral meds at home admitted for PNA. Weighs 60kg and initial FS 225.

Practice 40 yo man with DM2 on insulin at home admitted for DM foot ulcer. Weighs 100kg and initial FS 450.

NPH/Regular Total insulin dose split 2/3, 1/3 for AM and PM AM insulin split 2/3, 1/3 for NPH and Regular to be given together before breakfast PM insulin split ½, ½ for NPH and Regular to be given before bed

Practice 65 yo man with DM2 on PO meds (forgot regimen) admitted for ACS r/o. Weighs 72kg and initial FS 300.

Practice 85 yo man with DM2 and CKD2 on no meds at home admitted for PNA. Weighs 60kg and initial FS 190.

Practice 40 yo man with DM2 on insulin at home admitted for DM foot ulcer. Weighs 100kg and initial FS 450.

Adjustments Regimen is a starting point Daily adjustments of insulin based on corresponding Finger stick values AM, lunch, PM, HS until at goal Adjust based on differences in PO intake depending on meal

Adjustment Guidelines If all FS elevated, increase long acting If single value elevated, adjust corresponding insulin Increase by ~ 10-20% but can exceed depending on level of control Use rule to 1800/TDD to estimate effect of a unit of insulin

Adjustment Scenario 40 yo man with DM2 on insulin at home admitted for DM foot ulcer. Weighs 100kg and initial FS 450. FS: 350, 400, 275, 300 FS: 150, 450, 170, 250 FS: 300, 160, 180, 130

Diet changes NPO: Half long acting, hold short acting Enteral feeds: Bolus: used the same basal/bolus strategy timed with boluses Continuous: Single dose lantus or BID NPH TPN: insulin often added to TPN so work with pharmacy

Troubleshoot Several days to increase regimen to reach goal, then FS start fall below goal consistently Stable regimen with FS at goal, then sudden hypoglycemic event Inconsistent PO intake, lots of very elevated FS as well as hypoglycemic events

Sliding Scale Additional insulin to cover hyperglycemic events, given at each FS check Makes it difficult to interpret how your regimen is doing Should be used as a reminder to adjust the regimen not as a solution to hyperglycemia

70/30 Simplest regimen with basal/bolus insulin Only 2 injections/ day with no mixing Calculate TDD then 2/3, 1/3 in AM, PM

Type 1 DM Always need basal insulin Often carb count and adjust their own insulin Consider working with patient and nursing to facilitate acceptable plan

Discharge Use A1C to help guide need for outpatient insulin If previously controlled on PO meds, resume without insulin If continuing insulin, keep in mind changing insulin sensitivity and changes in diet Choose an insulin regimen that is realistic for the patient