Epidural analgesia guide

Epidural Analgesia

U N I V E R S I T Y O F W I S C O N

U N I V E R S I T Y O F W I S C O N S I N

S I N

H O S P I T A L A N D C L I N I C S

M A D I S O N , W I

A Self-Directed Learning Module

Third Edition

Perission granted to modify or adopt provided written credit given to University of Wisconsin Hospital &

Clinics

TABLE OF CONTENTS

I. Introduction

II. Content

Section 1

Benefits, Indications, and Contraindications

Section 2

Pain Transmission / Modulation

Section 3

The Epidural Space

Section 4

Epidural Catheter Placement

Section 5

Common Opioids and Local Anesthetics

Section 6

Nursing Assessment, Documentation, and

Management of Side Effects and Complications

Section 7

Patient / Family Teaching

Section 8

AP II Pump

III.

Post-test

IV. References

First Authored 1997 by:

Susan L. Schroeder, RN, MS

Clinical Nurse Specialist

Department of Nursing

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

UW Hospital and Clinics, Madison, WI

Revised 2000 by:

Deb Gordon, RN, MS

Clinical Nurse Specialist

Department of Nursing

UW Hospital and Clinics, Madison, WI

Sue Deeren RN, MS, NP

Clinical Nurse Specialist

Department of Anesthesiology

University of Wisconsin, Madison, WI

Michael Ford, MD

Assistant Professor

Department of Anesthesiology

University of Wisconsin, Madison, WI

Mark Schroeder, MD

Associate Professor

Department of Anesthesiology

University of Wisconsin, Madison, WI

Produced by the Department of Nursing Resources and Development

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

INTRODUCTION

Analgesia is now recognized as a significant contributor to

clinical outcomes

(1)

. The goal for pain management is to provide

the best analgesia with the least amount of side effects. Epidural
analgesia is a desirable method of pain relief because it provides
true segmental analgesia with little or no contribution from
systemic levels of opioids

(2)

. All of which may lead to excellent

analgesia with minimal side effects

(2,3)

Caring for patients who receive epidural analgesia requires

specialized knowledge regarding the placement of the epidural
catheter, management of the therapy, and monitoring for potential
side effects/complications

(1,3,4,5,6)

. This self-directed learning

module is essential information for the nurse clinician who cares
for patients receiving epidural analgesia.

After the completion of this self-directed

learning module, nurse clinicians will be able to:

o Identify the benefits, indications and contraindications for

epidural analgesia.

o Explain the transmission and modulation of pain stimuli as

related to epidural analgesia.

o Identify the spinal cord anatomy as related to the placement of

the epidural catheter.

o List the common medications used for epidural analgesia.

o Identify potential complications from epidural analgesia, the

required monitoring of patients receiving epidural analgesia, and
the specific actions to be taken if a complication occurs.

o Recognize common side effects from epidural analgesia, and list

appropriate actions to be taken in the management of these side
effects.

o Describe required nursing assessment and documentation as related

to epidural analgesia.

o Perform appropriate patient/family teaching for those patients

receiving epidural analgesia.

o Demonstrate the programming and use of the Baxter AP II infusion

Pump.

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

Prior to completing the

self-directed learning module:

o Review :

Nursing Policy & Procedure 6.13 Epidural and

Intrathecal Analgesia

2. AP II Programming Guide and/or Baxter AP II video

o Attend AP II Pump Inservice

Other recommended resources to review (available through Nursing
Staff Development, 263-6490):

de Leon-Casasola, O., Karabella, D., & Lema, M. (1996) Bowel
function recovery after radical hysterectomies: Thoracic epidural
bupivacaine-morphine versus intravenous patient-controlled
analgesia with morphine: A pilot study. Journal of Clinical
Anesthesia, 8, 87-92.

Liu S, Carpenter RL, Neal JM. (1995). Epidural anesthesia and
analgesia: their role in postoperative outcome. Anesthesiology
82(6) 1474-1506.

Naber, L., Jones, G. & Halm, M. (1994). Epidural analgesia for
effective pain control. Critical Care Nurse, October,
69-83.

Pasero C. (1998). Epidural Analgesia For Acute Pain Management.
American Society of Pain Management Nurses self directed learning
program. ASPMN, Pensacola, FL.

Pasero C, McCaffery M. (1999). Providing epidural analgesia: how to
maintain a delicate balance. Nursing, August, 34-40.

Instructions for use of the

self-directed learning module are:

1. Read the content material.

2. Complete the post-test.

3. Perform return demonstration on the use and programming of the AP

II pump to:

Deb Gordon, RN, CNS, Nursing Staff Development

Kathy Hansen, RN, CNS, Nursing Staff Development

Sue Deeren, RN, NP, Anesthesiology

Pain Resource Nurse on your Unit

o o • • •

For clarification or questions regarding this self-directed
learning module, please contact:

Deb Gordon, RN, CNS, Nursing Staff Development

263-6488,

pager

#7253

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

BENEFITS, INDICATIONS,

AND CONTRAINDICATIONS

Section 1

1.1 BENEFITS

Epidural analgesia provides very effective, prolonged segmental

analgesia

(3)

. Smaller doses of opioids can be used in the epidural

route than systemic routes (parenteral or oral) since the opioid is
administered more directly to the spinal opioid receptors. The
smaller epidural dose of opioids decreases the potential for
opioid-related side effects

(3,6)

. In addition to opioids, local

anesthetics can be administered epidurally in order to produce a
neural blockade that provides analgesia. Local anesthetics and
opioids can be used in combination, and are believed to act
synergistically. This combination allows the concentration of
local anesthetics and dose of opioids to be decreased.

The following benefits have been found with epidural analgesia:
o excellent analgesia

(2,3,6,7)

o less sedation

(7)

o earlier ambulation

(8)

o decreased incidence of pulmonary complications

(7,8,9)

o decreased incidence of venous thrombosis

(9)

o earlier return of bowel function

(8,10)

o decreased stress response

(7)

1.2 INDICATIONS FOR EPIDURAL ANALGESIA

o Post-operative pain management

(3,4,5,6,11)

Epidural analgesia appears to be most beneficial for the high-
risk surgical patient or for those recovering from extremely
large or painful surgical procedures. Such procedures include
thoracotomies, major upper abdominal, major abdominal vascular,
and orthopedic surgeries. The epidural infusion provides a
localized band of analgesia at the site of the incision.

o Multiple trauma

(3,4,6)

Epidural analgesia is especially beneficial for patients with
chest trauma, i.e.: rib fractures. The localized analgesia
helps the patient overcome the pain induced splinting that
contributes to the loss of pulmonary function which in turn may
lead to atelectasis and pneumonia.

o Chronic pain

(5,6,12)

Epidural analgesia can be used in the treatment of patients
experiencing an acute exacerbation of Complex Regional Pain
Syndrome (CRPS) by producing a sympathetic blockade using a
local anesthetic. This provides improved analgesia, and allows
the patient to participate in physical therapy which is vital in
the control of their symptoms. Epidural analgesia may also be
used for the treatment of other types of chronic pain such as
cancer pain.

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Hospital & Clinics

1.3 CONTRAINDICATIONS TO EPIDURAL ANALGESIA

Epidural analgesia is contraindicated in the presence of:

o Anticoagulation therapy

(3,4,5,6,13,14)- *

Note: see summary ASRA consensus

statement

next page

Anticoagulation therapy and neuraxial anesthesia used together
increase the risk of epidural hematoma which may lead to serious
adverse effects such as permanent paralysis. Anticoagulation
therapy should not be initiated or changed without first advising
the Acute Pain Service.

o Coagulopathies

(1,4,5,6,13,14)

Patients experiencing coagulopathies are at an increased risk for
an epidural hematoma.

o Decreased level of consciousness

(13)

Epidural analgesia may be implicated in any progression of
central nervous system dysfunction. Also pain management by
epidural analgesia requires accurate reports of pain levels by
patient.

o Systemic infection

(4,5,6,13)

Systemic infection or sepsis may lead to an infection in the
epidural space.

o A localized infection at the insertion site of the epidural

catheter

(4,5,6,13)

A localized infection at the site of insertion may lead also to
an infection in the epidural space.

o Increased intracranial pressure

(6)

An inadvertent dural puncture when trying to locate the epidural
space in a patient with increased intracranial pressure,
increases the chance of cerebellar or tentorial herniation due to
the loss of CSF.

o Lack of qualified nursing care to monitor patients for side

effects and complications

(1,4,5,6,15)

Epidural analgesia should only be used in hospital units where
the staff has received adequate training. Staff should be
knowledgeable concerning epidural catheter placement, epidural
medications, and the possible side effects and complications from
epidural analgesia.

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Hospital & Clinics

*SUMMARY OF THE AMERICAN SOCIETY OF REGIONAL ANESTHESIA'S CONSENSUS

STATEMENTS ON NEUAXIAL ANESTHESIA AND ANTICOAGULATION

ORAL ANTICOAGULANTS
For patients on chronic oral anticoagulation, the anticoagulant therapy must be stopped and the prothrombin time
(INR) measured prior to initiation of neuraxial block.

The concurrent use of medications that affect other components of the clotting mechanisms may increase the risk of
bleeding complications for patients receiving oral anticoagulants, and do so without influencing the prothrombin
time and INR. These medications include aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), antiplatelet
drugs, and heparin.

Neurological testing of sensory and motor function should be performed routinely during epidural analgesia for
patients on warfarin therapy. These checks should be continued after catheter removal for at least 24 hours, and
longer if the INR was >1.5 at the time of catheter removal.

ANTIPLATELET DRUGS
Antiplatelet drugs, by themselves, appear to represent no added significant risk for the development of spinal
hematoma in patients having epidural or spinal anesthesia. At this time, there do not seem to be specific concerns as
to the timing of a single shot or catheter technique in relationship to the dosing of NSAIDs, postoperative
monitoring, or timing of the neuraxial catheter removal.

FIBRINOLYTIC AND THROMBOLYTIC DRUGS
Patients receiving concurrent heparin with fibrinolytic and thrombolytic drugs are at high risk of adverse neuraxial
bleeding during spinal or epidural anesthesia and should be cautioned against receiving spinal or epidural
anesthetics except in highly unusual circumstances. If used, neurologic monitoring should be performed at least
every 2 hours or more frequently, and the infusion should be limited to drugs minimizing sensory and motor
blockade.

STANDARD HEPARIN
Subcutaneous (mini-dose) prophylaxis is not considered a contraindication to using neuraxial techniques. The risk
of neuraxial bleeding may be reduced by delaying the heparin injection until at least one hour after the block or
catheter placement. The catheter should be removed 1 hour before any subsequent heparin administration or 2-4
hours after the last heparin dose. Prolonged therapeutic anticoagulation appears to increase the risk of spinal
hematoma formation, especially if combined with other anticoagulants or thrombolytics and neuraxial blocks
should be avoided in this clinical setting.

LOW MOLECULAR WEIGHT HEPARIN
LMWH increases the risk of spinal hematoma. The decision to perform a neuraxial block must be made on an
individual basis and if performed extreme vigilance of the patient's neurologic status is warranted. A single-dose
spinal anesthetic may be the safest neuraxial technique and needle placement should occur at least 10-12 hours after
a dose of LMWH. Patients receiving higher doses of LMWH (e.g. enoxaparin 1mg/kg twice daily) will require
longer delays (24 hours). Neuraxial techniques should be avoided in patients administered a dose of LMWH two
hours preoperatively (general surgery patients), since needle placement occurs during peak anticoagulant therapy. It
is recommended that indwelling catheters be removed prior to initiation of LMWH. Timing of catheter removal is
of paramount importance and should be delayed for at least 10-12 hours after a dose of LMWH. Subsequent doses
of LMWH should be administered at least 2 hours or longer after catheter removal.

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PAIN TRANSMISSION

MODULATION OF PAIN

Section 2

Definition of terms:

Pain: An unpleasant sensory and emotional experience associated
with the actual or potential tissue damage.

Afferent Nerve: A nerve that transmits impulses from the periphery
toward the central nervous system.

Analgesia: Pain relief, the absence of pain in response to a
stimulus that normally would be painful.

Noxious stimulus: A stimulus that is damaging or potentially
damaging to body tissue.

Nociceptor: A nerve receptor that is preferentially sensitive to
noxious or potentially noxious stimuli.

Nociception: The process of encoding a painful sensation.

Modulation: The process whereby nociceptive transmission is
modified through a number of influences

(16,17)

o o • •

The body’s response to pain is protective in nature. Pain is a

warning signal to which the body responds to prevent further
injury. Noxious substances which are released in response to
damaged tissue initiate the nociceptive transmission. Afferent
nerve fibers respond to the nociceptive stimuli peripherally, and
relay this information to the spinal cord. Most of the nociceptive
input enters the spinal cord through the dorsal horn

(16,17,18)

In the dorsal horn, nociceptive neurotransmittors are released in

response to the nociceptive input which activate the second-order
dorsal horn neurons. The activation of the second order neurons
results in: 1) spinal reflex responses such as acute
vasoconstriction, muscle spasms, and increased sensitization of
nociceptors; and 2) activation of the ascending tracts which
transmits the nociceptive input to several regions within the brain

(16,18)

. This is where several responses to pain occur including the

perception of pain, and the emotional and behavioral responses.

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The modulation of nociceptive input occurs at several sites

including the opioid receptors located in the dorsal horn, and at
opioid receptors located supraspinally in such areas as the cortex,
hypothalamus and periaqueductal area. Neuropeptides such as
enkephalin molecules (endogenous opioids) bind with the opioid
receptors to modulate nociceptive input. Exogenous (administered)
opioids work in a similar fashion. These opioid receptors provide
the means by which spinal opioids are able to modulate pain
transmission

(18,19)

. (See diagram 1)

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THE EPIDURAL SPACE

Section 3

The epidural space is a ‘potential space’ that contains fatty

tissue and blood vessels; and is located between the bony vertebral
canal and the outer surface of the dura mater. Moving towards the
spinal cord from the epidural space are the membranes or meninges
that cover the spinal cord. They are: 1) the dura mater; 2) the
arachnoid mater; and 3) the pia mater which adheres tightly to the
spinal cord and brain. The subarachnoid space is the area that
lies between the arachnoid and pia mater, and contains the cerebral
spinal fluid (CSF)

(20,21)

. The vertebral column is stabilized by

ligaments. The ligamentum flavum is the structure through which
the epidural needle and catheter must pass when being inserted to
reach the epidural space

(2)

. (See Diagrams 2 & 3)

The epidural space contains fat which surrounds and pads the

spinal cord. This fat functions as a ‘depot’ for opioids and local
anesthetics when these medications are administered for epidural
analgesia

(4,13)

. Opioids administered into the epidural space diffuse

across the meninges and CSF to receptors in the dorsal horn of the
spinal cord.

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EPIDURAL CATHETER PLACEMENT

Section 4

A dermatome is the area of skin and soft tissue that is

innervated by a single spinal nerve root. (See diagram 4) The
epidural catheter is placed in a centrally located interspace so
that all of the affected dermatomes would receive the benefits of
the infusion

(22,23)

. Under aseptic conditions, the epidural catheter

is placed by a physician with the patient in the sitting or lateral
fetal position. Proper placement of the catheter is verified by
the physician through aspiration of the catheter and a small test
dose of a local anesthetic. Once proper placement of the catheter
is confirmed, the catheter is secured with tape and an occlusive,
transparent dressing. The extra length of the catheter is then
brought up over the shoulder, and secured with tape along its
length. A .22 micron filter is attached between the catheter and
the infusion tubing. The catheter and tubing should be clearly
labeled as ‘EPIDURAL CATHETER’

(3,6,13)

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Epidural catheters may be placed either in the thoracic, lumbar, or
caudal spaces. Most often thoracic catheters are placed for the
management of upper abdominal and thoracic sites of pain. However
lumbar catheters may also be placed for these sites. Lumbar and
caudal catheters are generally used for lower abdominal or lower
extremity sites

(22,23)

. If lumbar catheters are placed for upper

abdominal or thoracic sites, a larger dose/volume of opioid may be
needed. (See Diagram 5)

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COMMON OPIOIDS

AND LOCAL ANESTHETICS

Section 5

5.1 EPIDURAL

OPIOIDS

o Onset and duration of analgesia

A spinal opioid’s ability to dissolve in fat (lipid solubility)

influences its onset and duration of action. Lipophilic opioids
such as fentanyl, easily penetrate the dura/arachnoid membranes and
the spinal tissue, thus having a rapid onset of action. Unlike
systemically administered opioids, drug metabolism does not
influence the spinal opioids’ duration of action. The principle
routes of clearance of epidurally administered opioids are through
rapid vascular absorption or through slow rostral diffusion in the
CSF with elimination at the arachnoid granulations. Thus,
lipophilic opioids have a rapid onset of action but a limited
duration

(2,3,13,24)

. Meperidine, an intermediate lipophilic opioid, has

a moderate onset of action and duration. Caution must be used with
prolonged or high doses of meperidine, or with use in the elderly
or patients with impaired renal or hepatic function. Meperidine is
metabolized in the liver to normeperidine, a CNS neurotoxic
metabolite which can produce irritability, tremors, agitation,
myoclonus, and convulsions

(25)

. Generally though, epidural

meperidine infusions are at low doses and normeperidine toxicity is
not a problem.

Hydrophilic drugs (water soluble), such as morphine and

hydromorphone, have difficulty penetrating the membranes, and
diffuse more slowly. Therefore the onset of pain relief is slower.
Hydrophilic opioids tend to accumulate in the CSF, and are
transported rostrally to higher spinal levels eventually being
eliminated at the arachnoid granulations. Since hydrophilic
opioids have a greater ability for dermatomal spread than the
lipophilic, this enables them to provide analgesia for larger
areas. Conversely lipophilic opioids are limited in their ability
to spread throughout several dermatomes due to their rapid
penetration of spinal membranes and tissue. Additionally since
hydrophilic opioids spread rostrally and linger longer in the CSF,
their duration of action is longer. So hydrophilic opioids have a
slower onset and a longer duration

(2,13,24)

(See Diagram 6 and refer to Table 1)

Table 1 EPIDURAL OPIOIDS

(25)

DRUG

LIPID SOLUBILITY

ONSET

DURATION

Morphine

30 - 60 min.

6 - 24 hours

Hydromorphone

15-30

6 - 18 hours

Meperidine

5 - 10 min.

6 - 8 hours

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Fentanyl

800

5 min.

4 - 6 hours

o Potency of epidural opioid analgesia

The amount of opioid needed to provide a given level of analgesia

is much smaller when administered per spinal route. This is due to
the opioid being deposited in close proximity to the spinal cord
opioid receptor sites. This reduces dose requirements, and
improves the selectivity of spinal analgesia. Effective doses of
opioids when administered intrathecally are even smaller due to the
medication being deposited even closer to the receptor sites. When
comparing 24 hour dose requirements of parenteral vs. epidural vs.

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o Side effects of epidural opioid analgesia

While the ability of hydrophilic opioids to remain in the CSF

does provide some advantages such as prolonged duration, higher
potency, and extended dermatomal spread, the progressive rostral
spread may lead to potentially serious complications and/or mild
side effects as discussed below.

Respiratory

depression

with a hydrophilic opioid such as morphine

may occur at two distinct times. ‘Early respiratory depression’,
soon after administration, occurs mainly due to the vascular
absorption and circulatory redistribution to the brain. This is
similar to parenteral administration. ‘Delayed-onset respiratory
depression’ occurs due to the rostral spread of the opioid via the
CSF to the brainstem respiratory center. This may occur up to 24
hours later. With the use of lipophilic opioids, the ‘delayed-
onset respiratory depression’ is less likely to occur due to the
decreased tendency of lipophilic opioids to have a rostral spread.
‘Early-onset respiratory depression’ may occur though due to the
rapid uptake and circulation to the brainstem respiratory center

(2,3,4,5,6,13,24)

. The risk of respiratory depression is greatly increased

if systemic opioids (IV, IM, or PO) are co-administered with
epidural opioids.

Nausea and vomiting are also related to rostral spread of the

opioid in the CSF to the chemoreceptor trigger zone in the
brainstem

(2,4,5,6)

. This occurs in about 17% of post-operative

patients, similar to patients receiving parenteral opioids

(6,26)

Fortunately, the incidence is reduced after repeated doses, and can
often be managed with antiemetics

Pruritus

is frequently noted with epidural opioids, usually of

the face and chest. A rash is not normally detected. The cause
for pruritus is not clearly understood, but it may reflect
alterations in spinal and trigeminal nerve processing

(26,27,28)

. The

modulation of nociceptive input is interpreted at a higher level as
an itch. A recent study

(29)

indicates that there maybe changes in

the spinal efferent outflow, causing histamine to be released at
peripheral sites. Thus explaining why antihistamines may provide
effective treatment

(13,26)

. Another pruritus management option is to

administer a mixed opioid agonist-antagonist such as nalpuphine
(Nubain). Nalpuphine antagonizes mu opioid receptors which are
thought to be associated with respiratory depression and pruritus
and stimulates opioid kappa receptors, which produces analgesia. A
typical dose of nalpuphine for pruritis is 2.5-5.0 mg IV q6 hours
PRN.

Urinary retention occurs most often but not exclusively in young
males and is less likely with thoracic epidurals. It has been
reported to occur due to the relaxation of the bladder detrusor
muscle

(13,26)

5.2 LOCAL

ANESTHETICS

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Dilute local anesthetics when injected on or near a nerve will

result in the blockade of some nerve conduction. This may result
in the absence of pain, while motor and other sensory functions may
be unaffected. The term ‘differential block’ is used to describe
this phenomenon. Some nerves are less readily blocked than others
due to their size and extent of myelination. Local anesthetics
administered epidurally interrupt the nociceptive input at the
nerve roots as they return to the spinal column

(28)

Local anesthetics may differ according to: 1) potency; 2) speed

of onset; 3) duration of activity; and 4) ability to cause a
differential blockade of sensory and motor fibers

(26)

. Bupivacaine,

the most common local anesthetic used in continuous epidural
infusions, has a high anesthetic potency, a prolonged duration of
action, and will also provide adequate sensory analgesia with
minimal blockade of motor function

(28)

Local anesthetics are relatively free of side effects. However,

higher concentrations of local anesthetics will provide an
increased motor block (possibly limiting ambulation) and/or a
sympathetic blockade (resulting in resting or orthostatic
hypotension). Patients receiving epidural local anesthetic should
be kept well hydrated and monitored regularly for changes in lower
extremity motor strength and orthostatic hypotension.

A phenomenon called tachyphylaxis may also occur with the
administration of local anesthetics. This is the development of an
acute tolerance to the drug; the drug becomes less effective. The
coadministration of epidural local anesthetics and opioids has been
found to prevent the occurrence of tachyphylaxis. The exact
mechanism for this is still unclear

(28)

Although rare, epidural administration of a local anesthetic can

lead to high blood concentrations of local anesthetics causing
symptoms of systemic local anesthetic toxicity. A number of
factors influence the blood concentrations of local anesthetics
such as the dose of the drug, site of injection, speed of the
injection, or inadvertent injection directly into the blood
vessels. Systemic side effects primarily involve the central
nervous or cardiovascular systems

(30,31)

. The initial symptoms of CNS

toxicity are lightheadedness, dizziness, metallic taste, and
ringing in the ears. This may progress to an excitatory phase with
symptoms such as shivering, muscle twitching, tremors, and then
generalized convulsions. CNS depression may follow resulting in a
respiratory arrest. Cardiovascular systemic toxicity is initially
noted by hypotension which may be transient but this may progress
to profound hypotension, myocardial depression eventually resulting
in cardiac arrest and death

(32,33)

5.3 OPIOID AND LOCAL ANESTHETIC COMBINATIONS

Opioids and local anesthetics are believed to act

synergistically. By combining both in the epidural infusion, a
decreased concentration of the local anesthetic and a lower dose
of the opioid may be possible. This generally provides better
analgesia with fewer side effects

(2,13,34)

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5.4 COMMON EPIDURAL INFUSION

Common Opioid Concentrations

Common Local Anesthetics
Concentrations

Morphine 50 mcg/ml

Bupivacaine 0.1% (1mg/ml).

Hydromorphone 10mcg/ml

Bupivacaine 0.05% (0.5mg/ml)

Fentanyl 2-5mcg/ml

Ropivacaine 0.2% (2mg/ml)

Meperidine 2mg/ml

5.5 COMMON INFUSION RATES
5-14

cc/hour

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NURSING ASSESSMENT,

DOCUMENTATION, AND MANAGEMENT

OF SIDE EFFECTS AND COMPLICATIONS

Section 6

6.1 GENERAL PATIENT MANAGEMENT

o Maintain IV access while receiving epidural analgesia and for 8

hours following the last administration of medication.

(3,13)

o Epidural medications should be sterile, preservative-free (due to

the neurotoxicity of preservatives), and designated for
intraspinal use.

(6,26)

o Do not use alcohol on the epidural catheter or infusion tubing

due to the potential for neurotoxicity.

(6,24)

o No other opioid or CNS depressant should be administered to a

patient receiving epidural opioids due to the increased risk of
respiratory depression. If the patient is anxious, agitated, and
needs a sedative, notify the Acute Pain Service prior to starting
the sedative. It may be prudent to stop the epidural infusion and
provide analgesia through another route.

o No anticoagulation therapy should be initiated or changed before

notifying the Acute Pain Service. Anticoagulation therapy
increases the risk of epidural hematoma. Timing of catheter
placement and removal is of paramount importance in the presence
of anticoagulation therapy.

o Review Epidural Physician Orders

(13)

Noting:
1. The location of the epidural catheter
2. Initial preop opioid bolus dose, if given and when
3. Medication(s) ordered and the infusion rate
4. Specific recommendations for patient assessment
5. Orders to treat potential side effects/complications
6. When to notify the Anesthesiology Acute Pain Service

Notify by using the P-A-I-N pager ( # 7 2 4 6 )

6.2 ASSESSMENT OF ANALGESIA LEVEL

(3,5,13)

Assessment:

Assess the patient’s pain rating using patient-

specific pain scale (e.g. 0-10)

every 4 hours while awake, both at rest and with

activity

Documentation: Document patient’s pain ratings on Pain Management
flow sheet (UWHC #48)

Management: Notify the Acute Pain Service of inadequate analgesia

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6.3 ASSESSMENT AND MANAGEMENT OF SIDE EFFECTS

o Increased sedation / respiratory depression

(2,3,4,5,6,13,22,31,35,36)

A n i n c r e a s e d s e d a t i o n l e v e l w i l l o c c u r p r i o r t o r e s p i r a t o r y

d e p r e s s i o n

Assessment:

Assess sedation level/respiratory rate every hour

for the first 24 hours,

then every 4 hours, preferably by the same nurse

during each shift.

Documentation: Document levels on the Pain Management flow sheet

Warning:

Do not administer systemic opioids or CNS
depressants without approval of the Acute Pain
Service.

Management:

Notify the Acute Pain Service of a sedation score of

4 and / or

respiratory rate less than 10.

UWHC Sedation Scale:

N = Normal sleep
1 =

Anxious, agitated, or restless

2 =

Calm, cooperative to tranquil (normal patient’s

baseline without sedation)
3 =

Quiet, drowsy, responds to verbal commands

4 =

Asleep, brisk response to forehead tap or loud

verbal stimuli
5 =

Asleep, sluggish response to increasingly

vigorous stimuli
6 =

Unresponsive to painful stimuli

I f t h e s e d a t i o n s c o r e i s 5 a n d t h e r e s p i r a t o r y r a t e i s l e s s
t h a n 8

1. Stop the epidural infusion

2. Administer naloxone* as ordered on the Epidural Physician
orders

3. Notify the Acute Pain Service

4. Administer oxygen, check the patient’s oxygen saturation

level

•

Naloxone is an opioid antagonist that reverses the effects of
opioids. Usual dose is 100mcg IV given over 1 minute. Caution
must be taken to give it slowly because naloxone may cause
cardiopulmonary symptoms such as ventricular tachycardia and
pulmonary edema. The dose may need to be repeated every 3 - 5
minutes until the symptoms have been reversed.

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

o Nausea / Vomiting

(2,3,4,5,6,13,22,31)

Management: Administer anti-emetics as ordered, and notify the
Acute Pain Service

if the nausea/vomiting persists. Assess for other
possible causes and treat as appropriate.

o Pruritus

(2,3,4,5,6,13,22,31)

Management: Administer diphenhydramine (antihistamine) or

nalbuphine (opioid agonist-antagonist) as ordered
prn, and notify the Acute Pain Service if the
pruritus persists or becomes more severe. Assess for
other possible causes and treat as appropriate.

o Urinary retention

(2,3,4,5,6,13,22,31)

Management: The patient may have a foley catheter placed, or be
straight

catheterized prn. If the patient requies a second
straight catheterization consider placing a foley
catheter. The Acute Pain Service recommends not to
routinely discontinue the foley while the patient is
still receiving a lumbar epidural infusion. The
risk of urinary retention is greater in men and with
lower (lumbar or caudal) catheter placement.

o Orthostatic hypotension

(4,6,13,32,34)

Assessment: Assess BP and HR every 4 hours

Assess for orthostatic changes prior to ambulating

Management: Ensure adequate hydration and fluid replacement.

Notify the Acute Pain Service if changes are greater
than 20% from baseline.

o Sensory / Motor function loss

(3,4,5,13,30,31)

Assessment: Assess the patient for changes in sensory/motor
function

at least every 4 hours and more frequently if there
are changes. Ask the patient to point to numb and
tingling skin areas, and to bend their knees and
lift the buttocks off the mattress.

Management: Do not ambulate the patient if the patient complains
of

weakness, heaviness, or numbness/tingling in lower

extremities

Notify the Acute Pain Service of changes noted in

the

patient’s

sensory/motor

function

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Hospital & Clinics

6.4 ASSESS FOR POTENTIAL COMPLICATIONS OF EPIDURAL ANALGESIA

o Epidural abscess

(4,5,6,13,21,37)

Assessment: Assess the catheter insertion site every 8 hours for
signs of

infection i.e.: tenderness, erythema, swelling,

drainage.

Assess for changes in sensory/motor function every 4
hours including unexplained back pain, bowel or
bladder dysfunction, fever, or neck stiffness.

Management: Notify the Acute Pain Service of any changes noted

o Epidural hematoma

(6,13,21,35,38)

Assessment: Assess the catheter insertion site every 8 hours for
pain and or

swelling at the site.
Assess for changes in sensory/motor function every 4
hours,including progressive numbness, weakness, or
bowel and bladder dysfunction

Warning:

Do not administer Low Molecular Weight Heparin

without first advising the Acute Pain Service

Management: Notify the Acute Pain Service of these symptoms

o Subdural puncture

(6,13)

(The catheter may migrate into the subarachnoid space, causing an
overdose of opioid and local anesthetic)

Assessment: Assess the patient for a sudden or progressive
increase in side effects

such as sedation, loss of sensory and motor

function, hypotension

Management: Notify the Acute Pain Service immediately

o Migration of catheter into epidural vessels

(5,13)

(The catheter may migrate into the blood vessels of the epidural
space, causing the medications to be delivered systemically)

Assessment: Assess the catheter for blood in the tubing

Assess the patient’s pain level, inadequate

analgesia may occur

due to the small opioid dose being delivered

systemically

Assess the patient for symptoms of local anesthetic

toxicity such as

dizziness, lightheadedness, hypotension, agitation,

seizures

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

6.5 CATHETER AND DRESSING CARE

o Dressing care:

Notify the Acute Pain Service to reinforce or

change the dressing.

The epidural catheter is secured with adhesive

strips and covered with

a clear adhesive dressing. Manipulation of the

dressing may dislodge

the epidural catheter from the epidural space. It

is best if a member of

the Acute Pain Service attends to the dressing so

that assessment of

the position of the catheter is noted.

Do not change or reinforce the dressing

(5,6)

o Disconnection of the epidural catheter from the filter, or if the
epidural catheter or filter
is

cracked:

If disconnected, cover the ends with sterile gauze.

Notify the Acute Pain Service immediately

(13,22)

If the catheter or filter is cracked (clear fluid may

accumulate under dressing).

Notify the acute pain service immediately

(13,22,31)

6.6 DISCONTINUATION OF EPIDURAL CATHETER

(31)

The Acute Pain Service will remove the epidural catheter. The
decision to stop the epidural infusion and remove the epidural
catheter is made by either the Acute Pain Service or the
patient’s primary physicians. The Acute Pain Service will
remove the epidural catheter.

If an epidural catheter is removed accidentally, place the
catheter and attached dressing into a plastic bag and label
with the patient’s name. The APS will inspect the catheter to
ensure it was removed without breakage.

6.7 TRANSITION TO ALTERNATIVE MODES OF ANALGESIA

(30)

Studies are lacking and controversy exists over the correct
ratios to use when switching opioid-naïve patients from
various epidural opioids to parenteral or oral opioids. The
nurse should discuss the plan and clarify responsibility for

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Hospital & Clinics

PATIENT / FAMILY TEACHING

Section 7

The patient / family should be informed of the importance of pain

management to their well-being, and that the staff is eager to
provide adequate analgesia. The patient / family should be
instructed on:

1.

The use of pain rating scales

The different routes of analgesia administration

3. The possible side effects of the analgesic and the

management of these side effects.

Activity levels expected of the patient while receiving

epidural analgesia

(1,13)

The patient / family should also be given to read:

Health Facts For You:

•

Pain Management ---

- What Everyone Should Know (UWH #4299)

•

Epidural Analgesia (UWH #4322)

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Hospital & Clinics

AP II PUMP

Section 8

Review the Acute Pain Service Guidelines for use of the pump

and/or view the

Baxter AP II video (available through the Nursing Staff

Development office)

2.

Attend inservice on use of AP II pump.

Return demonstration on use and programming of AP II pump to:

Deb Gordon, RN

Nursing Staff Development

Kathy Hansen, RN

Nursing Staff Development

Sue Deeren, RN

Anesthesiology

Pain Resource Nurse on your unit

For more information, or for additional copies of this Self-

Directed Learning Module, please call Nursing Staff Development at

263-6490.

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

III. POST-TEST

True or False (Please record your answers on the answer sheet

provided)

_____ 1.

Exogenous opioids bind with opioid receptors to

modulate the nociceptive

transmission.

_____ 2.

Fat in the epidural space functions as a ‘depot’ for

the opioids and local anesthetics.

_____ 3.

Lipophilic opioids such as fentanyl, when

administered epidurally, have a rapid onset and a long
duration of action.

_____ 4.

Morphine, when administered epidurally, has a slower

onset but a longer duration of action when compared to
fentanyl.

_____ 5.

The dose of an opioid administered epidurally is

about the same as a parenteral dose.

_____ 6.

Common side effects of epidural opioids are nausea,

pruritus, and urinary retention.

_____ 7.

If the epidural catheter dressing is loose, the

nurse should reinforce the area with tape and a new
occlusive dressing.

_____ 8.

A sudden increase in a patient’s sedation level may

be due to the migration of the epidural catheter into the
subarachnoid space.

_____ 9.

All medications administered epidurally must be

preservative-free.

_____ 10.

The epidural catheter insertion site should be

assessed every 8 hours for tenderness, swelling, erythema,
or drainage.

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

Case examples with multiple choice questions

A 63 year old female was admitted to your unit at 1300 from the PACU

following a (R) Thoracotomy for cancer. The patient had an epidural
catheter inserted in the thoracic interspace 4 (T4) at 0700, and
preservative-free Morphine 2.5mg at 0800. She received both a general
anesthetic and an epidural infusion of bupivacaine during surgery.
Surgery and her stay in the PACU were without complications. An epidural
infusion of Morphine 50 mcg/ml and Bupivacaine 0.1% was started at
7cc/hr in the PACU. Your shift started at 2300, and received this
report:

Vital signs have been stable, currently BP 140/80 HR 88 RR 16 T

37.9

The patient is alert, and oriented x3

Epidural is infusing at 7 cc/hr

The patient complained of incisional pain earlier, and received

Morphine 2 mg IV at 1400 and 1600

Currently she denies pain

11.

This patient should have her respiratory rate and level of sedation

checked during your shift
tonight:

every 2 hours

every 4 hours

every

hour

one time this shift

12.

At 0100 you note her respiratory rate is 6 / min. Prior to this you

may have noticed:

a fall in blood pressure

an increased sedation level

increased pain level

none of the above

13.

Upon discovering this patient with a respiratory rate of 6 / min.,

you assess the patient’s

sedation level and rate it a 5. You should:

call the Acute Pain Service

stop the epidural infusion and monitor the patient

stimulate the patient and call the Acute Pain Service

stop the epidural infusion, administer Naloxone as ordered on

the Physician

Epidural Order sheet, and notify the Acute Pain Service

14.

Earlier in the day, the patient had received IV Morphine for reports

of increased pain.
The

patient:

denied pain following the IV Morphine, this was appropriate

should not have received IV Morphine along with the epidural

infusion due to the

increase risk of respiratory depression. The Acute Pain

Service should be notified of
inadequate

analgesia

should not have received IV Morphine with the epidural

infusion, and the Surgery

Service should be notified

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

A healthy 61 year old male is S/P Colon Resection had an epidural

catheter inserted in the T 12 interspace prior to surgery, and has
Morphine 50 mcg/ml and Bupivacaine 0.1% infusing currently at 10 cc/hr.
On Post-op Day (POD)#1, he had increased pain so the infusion was
increased from 8cc/hr to 10cc/hr. On POD#2, you are to ambulate the
patient. Currently he is denying pain.

15.

As you prepare to ambulate the patient, he reports that his legs

feel heavy and areas

on his thighs feel numb. This is most likely due to:

the local anesthetic in the epidural infusion

generalized post-op weakness

lying in one position too long during the night

development of an epidural abcess

16.

Prior to ambulating the patient, you should:

assess his lower extremities for any further changes in
sensory / motor function, and notify the Acute Pain Service of
his symptoms i.e.: heaviness, numbness, or other changes

stop the epidural infusion prior to ambulating the patient

not worry about these symptoms

notify the Surgical Service

o • • •

A 29 year old male, S/P a Total Colectomy-Pouch, had an epidural

catheter placed at T 9 prior to surgery and is receiving Morphine 50
mcg/ml and Bupivacaine 0.1% at 8 cc/hr for pain management. The patient
has been progressing very well. He has denied pain at rest, and reports
a ‘2-3’ pain level with ambulation which he has been satisfied with for
the last two days. In the early hours of POD#3, the patient reports that
over the last 2 hours his pain at rest has increased from ‘0’ to ‘5-6’.
The nurse assesses the patient for any other physical changes and finds
none.

17.

The nurse should:

also assess the epidural infusion pump and tubing for problems

such as kinked

tubing, and assess the catheter site for catheter displacement

or leakage

just notify the Acute Pain Service

wait another hour and reassess patient

just notify the Surgical Service

18.

When patients have inadequate analgesia, the nurse should notify:

the Surgical Service

the anesthesiologist who inserted the epidural catheter

the Acute Pain Service in the morning

the Acute Pain Service

o • • •

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

On your unit is a 42 year old female who is S/P (R) Thoracotomy, and

had an epidural catheter inserted at the interspace T 6 preoperatively.
She is receiving an infusion of Meperidine 2mg/ml and Bupivacaine 0.1% at
6cc/hr. Today (POD#1), you are to start to ambulate the patient. She
denies incisional pain, numbness or heaviness in her legs. She does tell
you that when she sat up in bed this am she felt very dizzy.

19.

Prior to ambulating her, the nurse should:

make sure there is adequate help prior to getting her out of

bed

check for orthostatic changes in the patient’s heart rate and

blood pressure

just notify the Surgical Service

none of the above

20.

On POD#3, the surgeons request that the epidural catheter be

discontinued. The nurse
should:

discontinue the catheter

remind the Surgical Service to discontinue the catheter

should notify the Acute Pain Service, who will discontinue the

catheter

none of the above

o • • •

Permission granted to modify or adopt provided written credit given to University of Wisconsin

Hospital & Clinics

IV.

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