Avoiding Errors With Insulin Therapy

D A N G E R Z O N E

Author: Susan Paparella, RN, MSN, Huntingdon Valley, Pa

Susan Paparella, Bux-Mont Chapter, is Director for Consulting Services,Institute for Safe Medication Practices (ISMP*), Huntingdon Valley,Pa, and a member of ENA’s ED Safety Workgroup.

For correspondence, write: Susan Paparella, RN, MSN, 1800 ByberryRd, Suite 810, Huntingdon Valley, PA 19006; E-mail: spaparella@ismp.org.

J Emerg Nurs 2006;32:325-8.

0099-1764/$32.00

Copyright n 2006 by the Emergency Nurses Association.

doi: 10.1016/j.jen.2006.03.016

*ISMP is a nonprofit organization that works closely with health care practi-tioners, consumers, hospitals, regulatory agencies, and professional organi-zations to educate caregivers about preventing medication errors. ISMP isthe premier international resource on safe medication practices in health care in-stitutions. If you would like to report medication errors to help others, E-mailus at: ismpinfo@ismp.org or call (800)FAIL-SAF(e). This Medication ErrorReporting Program keeps information confidential and secure. We will includeonly the level of detail that the reporter wishes in our publications.

August 2006 32:4

here is no doubt that insulin therapy has become

Tmore complex during the past decade. The addi-

tion of analog insulin mixtures that combine short-

acting and long-acting insulin therapy in a single dose, the

problem with similar names and look-alike packaging, the

use of the abbreviation ‘‘u’’ to indicate units, and a wide

variation in patient doses and onset of action, along with

recent changes in delivery methods (continuous insulin

pumps and prefilled pens), have changed our traditional

thinking about insulin therapy.1 Unfortunately, along with

this added complexity comes an increased risk of error, as

shown by the examples below.

How errors happen

Recently, a nurse taking a patient’s history used the letter

‘‘u’’ to indicate the units of insulin associated with each

dose (Figure 1). The prescriber misinterpreted the docu-

mented dose and wrote for significantly different doses

than what the patient had been taking at home (Figure 2).

The prescriber in his order also inappropriately used ‘‘u’’

to indicate units, but thankfully the order was not again

misread as an additional ‘‘4’’ units for each dose. A single

overdose of insulin was administered; no serious harm

occurred, and thus the error was not recognized. A second

error was later averted from the same order when the

nurse mentioned to the patient, ‘‘Here’s your 44 units of

insulin.’’ The patient responded, 44 units? I take 4 units!’’2

In other examples, drug name confusion is often at

the root of the problem. In one reported case, Humalog

was inappropriately prescribed as a 70/30 mixture (when

no such ratio dose exists), and Humulin 70/30 was subse-

quently administered in error from ED stock. In another

JOURNAL OF EMERGENCY NURSING 325

FIGURE 1

The symbol ‘‘u’’ (to represent units) was used to document

insulin doses in the patient’s medication history.

FIGURE 2

The prescriber misinterpreted the ‘‘u’’ symbols on themedication history as ‘‘4s’’ and erroneously ordered doses

based on this understanding.

D A N G E R Z O N E / P a p a r e l l a

hospital, plain Humalog was ordered, and luckily the nurse

caught herself as she began to draw up Humalog 75/25.

Patterns of error have been reported related to the confu-

sion of Lente (insulin zinc suspension) and Lantus insulin.

In several instances the clarification of the terms ‘‘Lenti’’

and ‘‘Lentis’’ were erroneously changed to ‘‘Lantus.’’3

Many hospitals have reported adverse events result-

ing from common name confusion between Novolin 70/30

(70% NPH human insulin isophane suspension, 30% reg-

ular, human insulin) and Novolog Mix 70/30 (70% insulin

aspart protamine suspension and 30% insulin aspart). In most

cases, the word ‘‘mix’’ was not part of the order, but with

similar sounding names and strengths of these 2 products, it

is unlikely that this word alone would have made the dif-

ference. In fact, the confusion between these 2 products is

so common among all types of practitioners, a recent dis-

pensing error by a pharmacist actually resulted in the patient

receiving their correct insulin! On admission orders the pre-

scriber wrote for Novolog Mix 70/30, but the pharmacist

entered Novolin 70/30 into the computer system. The patient

received this dose for 2 days before an astute nurse caught

the error. The pharmacist suggested the use of Humalog

75/25 (since Novolog Mix was not on the formulary). In-

sisting that the patient remain on the same therapy as at

home, the family was asked to bring in the patient’s insulin

supply for use in the hospital. Upon inspection, the insulin

vial was actually Novolin 70/30, the same insulin the patient

had been getting inadvertently all along!4

Other adverse events reported with insulin therapy

include a severe hypoglycemic episode following the use of

a vial of ‘‘U-500’’ insulin that was inadvertently dispensed

to an emergency department, instead of the usual ‘‘U-100’’

strength, and inadvertent use of Lantus (insulin glargine) in

place of regular insulin to mix an insulin infusion.5

326 J

Traditional thinking about insulin therapy also has

changed, making the administration more complex. In the

past, nurses learned that only ‘‘rapid-acting insulin is clear.’’

This thought is no longer true because we now use Lantus,

a clear, long-acting insulin. Also, the statement that ‘‘only

clear insulin can be given intravenously’’ is misleading, be-

cause we now use Humalog, Novolog, and Lantus; all are

clear insulins, but none are indicated for intravenous use.6

OUR

Many hospitals have reported adverseevents resulting from common nameconfusion between Novolin 70/30(70% NPH human insulin isophanesuspension, 30% regular, humaninsulin) and Novolog Mix 70/30 (70%insulin aspart protamine suspensionand 30% insulin aspart).

The aforementioned errors represent only a very small

number of the insulin errors found in scientific studies

and data from voluntary reporting programs such as the

United States Pharmacopeia–Institute for Safe Medication

Practices (USP-ISMP) Medication Error Reporting Pro-

gram and the USP’s MEDMARX program. According to

MEDMARX data, errors with insulin therapy in the emer-

gency department represent one of the leading medication

errors resulting in patient harm.7 The most commonly re-

ported adverse events with insulin include omission errors

(leading to hyperglycemia) and improper doses (leading to

hyperglycemia or hypoglycemia).8

NAL OF EMERGENCY NURSING 32:4 August 2006

D A N G E R Z O N E / P a p a r e l l a

What can I do?

As with all high-alert medications, insulin deserves careful

attention, not only in the emergency department but in

every setting. To reduce adverse events with insulin therapy,

nurses should consider the following:. Obtain an accurate medication history, including the

name, strength, dose, and timing of each insulin dose.

Ask pertinent questions to detect possible confusion

between look-alike and sound-alike products. Encour-

age patients and families to bring in the insulin vials,

if necessary, for name and dose validation.. Avoid the dangerous use of the abbreviation ‘‘u’’ to in-

dicate the number of units and adhere to the National

Patient Safety Goal [2b] from the Joint Commission

on Accreditation of Healthcare Organizations.9

. Avoid verbal orders for insulin unless it is a true emer-

gency. Always write down and read back all verbal

and telephone orders, using single digit validation,

(eg, ‘‘one-four’’ for fourteen, so as not to be confused

with ‘‘forty’’).. Safely store insulin vials. Limit the variety of insulin

and strengths available in the emergency department

to avoid confusion. Avoid leaving insulin vials on

top of counters and automated dispensing cabinets.

Separate look-alike packages as much as possible, and

apply auxiliary labels as reminders to product pack-

ages that are similar. Work with the pharmacy to

add tall-man nomenclature to automated dispens-

ing cabinet screens and other storage locations to dif-

ferentiate look-alike insulin names (eg, HumuLIN vs

HumaLOG).. Centralize high-risk, error-prone processes by having

the pharmacy prepare all insulin infusions (as much

as possible). Use a single, standardized concentration

for insulin infusions, and provide nurses with infu-

sion charts to validate all calculations and dose titra-

tions. If smart pumps are used, ensure that hard stops

are used for insulin infusion rates, so maximally safe

doses cannot be inadvertently bypassed.. Employ an independent, double-check process for

all insulin doses. Double checks in an emergency de-

partment can be time consuming and cumbersome

and therefore should not be used with all medi-

cations. However, given what we know about the

August 2006 32:4

frequency of adverse events and patient harm with

insulin, double checks for this high-alert medication

are prudent!. Provide staff with ongoing education regarding new

insulin products and methods of delivery. Have the

pharmacy prepare a chart that lists all insulin prod-

ucts used in your facility, including generic names,

concentrations, onset, peak, duration of action, ac-

ceptable routes of administration, mixing instructions,

and time of delivery in relationship to meals. Develop

policies for managing patients who have continuous

insulin infusion pumps when they arrive at the emer-

gency department.1

. Monitor a patient’s response by obtaining point-of-

care glucose testing as appropriate. Always remember

that diabetic patients in the emergency department

may not have had the opportunity to eat a regular

meal or take their insulin dose as they normally would

have at home. Pay close attention to the patient to

observe for signs and symptoms of hypoglycemia

or hyperglycemia.

JOUR

Avoid verbal orders for insulin unless itis a true emergency. Always write downand read back all verbal and telephoneorders, using single digit validation,(eg, ‘‘one-four’’ for fourteen, so as notto be confused with ‘‘forty’’).

Don’t let your guard down and assume that there are

no problems with insulin in your emergency department.

Proactively look for ways to reduce the risks often asso-

ciated with insulin use and work with your colleagues to

address them today.

REFERENCES

1. Institute for Safe Medication Practices. ISMP Medication SafetyAlert! Complexity of insulin therapy has risen sharply in the pastdecade—Part II. 2002;7(9):1-2.

2. Institute for Safe Medication Practices. ISMP Medication SafetyAlert! Stop U be 4 errors. Safety Brief 2004;9(21):1.

3. Institute for Safe Medication Practices. ISMP Medication SafetyAlert! Proliferation of insulin combination products increases op-portunities for errors. 2002;7(24):2.

NAL OF EMERGENCY NURSING 327

D A N G E R Z O N E / P a p a r e l l a

4. Institute for Safe Medication Practices. ISMP Medication SafetyAlert! Getting the right insulin is becoming a real crapshoot.2004;9(14):2-3.

5. Institute for Safe Medication Practices. ISMP Medication SafetyAlert! Complexity of insulin therapy has risen sharply in the pastdecade—Part 1 2002;7(8):1-2.

6. United States Pharmacopeia–Institute for Safe Medication Prac-tices. Medication Error Reporting Program. Confidential data-base 1971–present (accessed March 2006). Huntingdon Valley(PA): The Institute.

7. Santell JP, Hicks RW, Cousins DD. Medication errors in emer-gency department settings—5 year review [online; retrieved 2006March]. Available from: URL: http://www.usp.org/patientSafety/resources/posters/posterEmergencyDept5yr.htm

8. United States Pharmacopeia. Patient safety CAPSLinkk. Insu-lin errors: a common problem [online; retrieved 2006 March].Available from: URL: http://www.usp.org/pdf/EN/patientSafety/capsLink2003-07-01.pdf

9. Joint Commission on Accreditation of Healthcare Organizations.National patient safety goals [online; retrieved 2006 March].Available from: URL: http://www.jcaho.org/PatientSafety/NationalPatientSafetyGoals/06_npsg_cah.htm and http://www.jcaho.org/NR/rdonlyres/2329F8F5-6EC5-4E21-B932 54B2B7D53F00/0/06_dnu_list.pdf

Contributions for this column are welcomed and encouraged.Submissions may be sent to:

Susan Paparella, RN, MSN 1800 Byberry Rd, Suite 810,Huntingdon Valley, PA 19006

215 947-7797 . spaparella@ismp.org

328 JOURNAL OF EMERGENCY NURSING 32:4 August 2006