Transcript Insulin Use In Outpatient and Inpatient Settings

Greg Cook, MD
Endocrinology Fellow
Objectives
 Become familiar with different types of insulin and
their actions
 Understand how various insulin regimens compare and
contrast with endogenous insulin production
 Become comfortable initiating and managing insulin in
the outpatient setting
 Learn basics of inpatient insulin therapy
 Learn how to use insulin to help address hyperglycemia
caused by glucocorticoids or enteral nutrition
Case I
45 yo man with 12 year history of DM type II presents for initial
visit to outpatient clinic. He is currently on metformin 1 gram
BID and glipizide 10mg BID. He monitors his glucoses
infrequently and reports fasting values of 200-250. His mother
recently died from diabetic complications, and he is very
concerned about developing similar problems himself.
Exam: Wt 242 lb (110 kg), BP is controlled
Obese, +acanthosis nigricans on neck
Labs: Serum glucose 286, Cr 1.3, Hgb A1c 9.6
In addition to encouraging dietary and lifestyle changes, how
would you manage his diabetes?
Acanthosis Nigricans
Derm Atlas – www. dermatlas.med.jhmi.edu
Types of Insulin
Onset (h)
Peak (h)
Effective Duration (h)
Rapid Acting
Insulin lispro (Humalog)
Insulin aspart (Novolog)
Insulin glulisine (Apidra)
<0.3-0.5
<0.25
<0.25
0.5-2.5
0.5-1.0
1-1.5
3-6.5
3-5
3-5
Short Acting
Regular (Humulin R or Novolin R)
0.5-1.0
2-3
3-6
Intermediate Acting
NPH (Humulin N or Novolin N)
2-4
4-10
10-16
Long Acting
Insulin glargine (Lantus)
Insulin detemir (Levemir)
2-4
flat
0.8-2
(dose dependent)
20-24
Dose Dependent
12 hr for 0.2 U/kg
20 hr for 0.4u/kg, up to 24 hr (binds to albumin)
Mixes
Humulin/Novolin 70/30 (NPH/Regular)
Humalog/Novolog 75/25 (Insulin lispro/aspart protamine/lispro/aspart)
Pharmacokinetics of Various Insulin
Insulin Analogues NEJM 2005: 352; 174-83
Pharmacokinetics of Various Insulin
Blood Glucose Goals
 Fasting Glucose: 70-130
 Pre-prandial goal: 70-130
 Postprandial goal: <180
Terminology
 Basal Insulin:
 Long acting insulin. Required in all type I patients, and
patients over glycemic target. Required even when NPO
 Prandial (Nutritional) Insulin:
 Scheduled short acting insulin given in anticipation of
carbohydrate induced hyperglycemic excursion
 Adjust amount given if nutrition is diminished or interrupted
 Correction Insulin:
 Short acting insulin given in addition to scheduled insulin as a
response to unexpected hyperglycemia. If this is used
extensively, then scheduled insulin should be adjusted or
added
Subcutaneous Insulin Order Sets and Protocols: Effective Design and Implementation Strategies. Journal of Hospital Medicine:
Vol 3, Issue 5, supplement 5 – S29-S41
Glucose Control in Type II Diabetes
Case I - Treatment
 Initiate basal therapy with insulin glargine or NPH
 Calculation of basal insulin:
 Initiate with 0.2-0.4 units/kg and higher for patients with
known insulin resistance
 Would start with 0.3 units/kg, or more, in this patient with
obesity and acanthosis
 Weight: 110kg
 0.3 x 110 = 33 units, rounded to nearest even # = 34 units.
 Written instructions to self-titrate dose by 2-4 units every 4
days for fasting glucoses > 130.
 Would also suggest he stop at 60 units (0.5 units/kg).
 Consider fast to evaluate basal dose
 Add prandial insulin coverage, starting with largest meal
Management of Hyperglycemia in Type 2 Diabetes: A Consensus Algorithm for the Initiation and
Adjustment of Therapy Diabetes Care 2006, Vol 29, number 8 1963-1972
Case II
32 yo overweight man with DM type II currently on
Novolin 70/30 insulin, 30 units with breakfast and 20 units
with dinner.
Review of glucose log shows fasting glucoses around
200’s and pre-dinner glucoses (220’s), with frequent
hypoglycemia occurring predominately before lunch,
mainly on days that he eats a late lunch. He always eats a
substantial bedtime snack due to a memorable episode of
nighttime hypoglycemia.
He has gained 10 pounds in last 3 months and is now
220 pounds. He wants to minimize number of insulin
injections.
What adjustments would you make?
Glucose Levels and Insulin physiology in
Non-Diabetics
Mixed Insulin Regimens
Diabetes Education Online – University of California San Francisco (www.deo.ucsf.edu/.../graph_sliding_premixed2.gif)
Case II - Treatment
 Current regimen:
 30 units 70/30 in AM = 21 units N, 9 units R
 20 units 70/30 in PM = 14 units N, 6 units R
 Calculation of total daily insulin dose:
 0.4 – 0.8 units x weight (kg), based on insulin sensitivity
 Case II: 0.5 x 100 = 50 units/day
 50% as basal, 50% as bolus
 Basal = 25, Bolus = 25
 Could change to:
 NPH 18 units in AM mixed with Aspart 8 units AC breakfast

Additional NPH at breakfast will help cover lunchtime hyperglycemia
 Aspart 10 units AC dinner (his biggest meal)
 NPH 12 units HS
NPH and Rapid Acting Insulin
NPH AM and AC dinner
NPH AM and HS
Case III
24 yo man presented 3 days ago with DKA and was
diagnosed with type I diabetes. He is currently on an
insulin infusion. He has received 40 units of insulin
over the last 24 hours (avg = 1.67 units/hr), is eating a
regular diet, and is ready for transfer to the floor.
Exam: Wt 176 lbs (80kg)
How would you transition him to SC Insulin?
Intensive Insulin Therapy
Intensive Insulin Therapy
Case III
 Calculation of Total Daily Dose (TDD) of Insulin
 1. Using Insulin Infusion Information


80% of total dose: 0.8 x 40 = 32 units
Avg rate x 20: 1.67 x 20 = 32 units

May represent only basal amount if pt was NPO during infusion
 2. Calculation based on body weight
 0.4-0.6 units/kg for patients without significant insulin
resistance: 0.4units/kg x 80kg = 32 units
 Calculation of basal insulin:
 50% of TDD = 16 units or 0.2 units/kg x 32kg = 16 units

Be sure to give basal insulin at least 2 hours prior to stopping
insulin infusion
Case III continued
 Calculation of prandial insulin:
1. 50 % of TDD divided between 3 meals: 16 units – approximately 5 units/meal
2. Carbohydrate ratio: (“Rule of 500”)
 500/TDD of insulin = how many grams of CHO 1 unit of insulin will cover
 Example: 500/32 units = 15.625 – round to 15
 One unit of meal-time insulin for every 15 grams of carbohydrates
 Meals at MCV contain approx. 60 grams of CHO. For our patient, 4 units for each meal
would be a starting point
 Calculation of Correction Factor: (“Rule of 1500”)
 1500/ Total Daily Dose of Insulin = how many mg/dl 1 unit of insulin will lower
blood sugar
 Example: 1500/32units = 46.875 – rounded up 50


One unit of insulin should lower glucose by 50 mg/dl
For glucose of 350, 4 units of Aspart should lower level to 150
Examples of Standardized
Correction Doses
** Note that HS correction dose is significantly less and maybe zero **
Subcutaneous Insulin Order Sets and Protocols: Effective Design and Implementation Strategies. Journal of Hospital Medicine:
Vol 3, Issue 5, supplement 5 – S29-S41
Case III -Continued
 Patient does not like hospital food and eats varying
amounts of meal. What you should do?
 Patient is going to be made NPO for procedure. What
should you do?
Case III - Continued
 NPO status
 If diabetic, especially type I, is to be NPO, be sure to continue
basal insulin


Can decrease dose by 10% or 20% if uncertain of true basal needs
Change glucose monitoring to Q 6 hours
 If patient’s appetite or PO intake is uncertain
 Give mealtime Aspart after the meal
 Can give ½ dose (2 units, for example) if about 50% of meal is
eaten
 If patient is able to count carbohydrates, he/she could tell
nurse how much insulin to give after the meal, based on
amount eaten
Case III Glucoses
Insulin regimen
Basal Insulin:
Prandial Insulin:
Correction Factor:
Glucoses
Glargine 16 units QAM
Aspart 5 units AC meals
1 unit/50 mg/dl above 150
Date
AC B
AC L
AC D
HS
7/10
175
122
189
115
7/11
192
101
210
120
What adjustments would you make to insulin regimen?
Case IV
55 yo with DM type II, admitted with pneumonia.
Meds: Glyburide 10mg daily
Metformin 1 gram BID
Exam: Wt 225 pounds (102 kg)
Labs: Serum Glucose 285
Cr 1.5 (baseline of 1.2)
Hgb A1c two months ago was 8.1
How would your manage his diabetes?
Hyperglycemia in the Hospital
Management of Hyperglycemia in the Hospital Setting NEJM 335:18 Nov 2006
Inpatient Management of Diabetes
 Every diabetic patient should have recent A1c to assess
control on diabetic regimen. If unknown or not
recent, order A1c on admit
 If A1c is <8%, outpatient regimen can be considered. If
on oral meds, will need to verify there are no
contraindications (renal, liver, and cardiac function,
other medications, procedures, nutritional status, etc)
 If A1c is >8% will need basal insulin, if on oral meds. If
on insulin, will need adjustments to prior insulin
regimen
 Order Accuchecks AC meals and HS. Q6 hours if NPO
Inpatient Management of Diabetes
 Basal insulin: 0.2-0.4 units/kg in 2 divided doses for NPH.
Glargine can be given in AM or bedtime
 Prandial Insulin: MCV meals contain 60 g of CHO
 Use “rule of 500” to calculate, or can start with between 4
(CHO 1:15) to 6 (CHO ratio of 1:10) units AC meals
 Correction Dose:
 Would at least provide correction for glucoses >300
 Aspart 6 units for glucoses >300 is reasonable for most
patients
 Use rule of 1500 to adjust. For example, if correction factor
is 1:20 and glucose is 350, with target glucose of 150, the
difference is 200. 200/20 = 10 units. 10 units of Aspart
should lower glucose of 350 to 150 range
Case IV
 Total Daily Dose (TDD) : 0.6 units/kg = 0.6 x 102 = 60 Units
 Basal Insulin: 50% of TDD = 30 units or 0.3 units/kg x 102 = 30
 NPH 15 units AM and HS
 Glargine 30 units
 Prandial Insulin:
A. 50 % of TDD = 30 units

Aspart 10 units AC meals
B. Rule of 500 = 500/60 = 8.33. For 60g CHO/meal. 60/8.3 =7

Aspart 7 units AC meals
 Correction Dose:
A. Aspart 6 units prn for glucose > 300.
B. Rule of 1500: 1500/60 = 25. 1 U of insulin lowers glucose by 25
Case IV
Correction Dose
Glucose
< 70
71-150
151-175
176-200
201-225
226-250
251-275
276-300
301-325
326-350
350-400
400+
Insulin
Assess patient, treat
No additional insulin
1 unit
2 units
3 units
4 units
5 units
6 units
7 units
8 units
10 units
10 units and call MD
Glucose
<70
70-150
151-200
201-250
251-300
301-350
351-400
400 +
Insulin
Assess + treat
None
2 units
4 units
6 units
8 units
10 units
10 units + call
Case V
65 yo with DM type II and COPD admitted with COPD
exacerbation. Home regimen was NPH 20 units AM,
HS and Aspart 10 units AC breakfast and AC dinner.
He is to be on prednisone 60mg daily as an inpatient and
then will receive prednisone taper over 10 days on
discharge
Exam: Weight 80 kg
How would you adjust his insulin regiment to account
for hyperglycemic effects of corticosteroid?
Case V
 Corticosteroids induce insulin resistance
 Although prednisone is dosed every 24 hours,
hyperglycemic effect is only a little over 12 hours

Once above 40mg, increasing doses of prednisone do not have
added hyperglycemic effects
 NPH’s has a duration of action to cover this effect

NPH 0.1 units/kg for every 10mg of prednisone up to 40 mg
Case V
For our 80 kg patient:
Dose of prednisone
60mg
40mg
20mg
10mg
NPH to be added home regimen
0.4 U/kg x 80kg = 32 units
0.4 U/kg x 80kg = 32 units
0.2 U/kg x 80kg = 16 units
0.1 U/kg x 80 kg = 8 units
For 60 mg of prednisone, he would take 20 U NPH + 32 U NPH =
52 U NPH in AM at the same time as prednisone
He will continue 20 U NPH at bedtime and same mealtime
Aspart insulin He may likely need more dinner Aspart while on
prednisone
Case VI
60 yo with DM type II, laryngeal cancer, s/p surgery. He
is currently on continuous TFs with Two Cal HN at 60
ml per hour. He is unsure of his home diabetes
regimen.
Exam: Weight 85 kg
Labs: Hgb A1c is 8.4
How would you control his glucoses while on the TFs?
Case VI
1. Calculate Total Daily Dose of Insulin
0.6 x 85 kg = 51 Units (50 units)
2. Calculate basal needs: 0.3 units/kg x 85 = 25.5 units (25 units)
2. Rule of 500 to calculate carbohydrate ratio
500/50 = 10 1 unit will cover 10g of carbohydrates
3. Calculate total grams of carbohydrates to be covered
-1st calculate total amount (volume) of TFs
60 ml/hr x 24 hours = 1440 ml/day
-Next calculate how many grams of carbohydrates (CHO) this gives/day
Two cal HN has 52 g of CHO per 8 fl oz can (236ml) or 0.22 g CHO/ml
0.22 g CHO/ml x 1440 ml/day = 317 g CHO/day
-Finally calculate how much insulin is needed to cover CHO content of TFs
317 g CHO/day x 1U/10g CHO = 31.7 or 32 units
4. Basal insulin + Insulin to cover TFs = 25 U + 32 U = 57 Units
Case IV
 Options for TF coverage:
 Glargine daily, Regular every 6 hr, Aspart every 4 hr, or
NPH every 8 hr
 Tube feeds tend to be interrupted often (i.e. for procedures
or because the patients pull them out)
 For our patient, we would choose NPH every 8 hours
 57 units total/ 3 = 19 units NPH Q 8 hours
 *If TFs are stopped, he will need D10 infusion to cover NPH
Key Points
 Individualize insulin therapy based on
 Etiology of diabetes
 Weight, BMI and anticipated insulin resistance
 Clinical setting- inpatient vs outpatient
 Patient’s diet or nutritional status
 Treatment goals
The End
Any Questions?