in whom motor

weakness would be detrimental, for example, the anesthesia care

provider may prescribe an epidural analgesic solution containing

an opioid only (no local anesthetic). Monitoring for efficacy and

adverse effects of epidural analgesia should include pain intensity and quality, response to treatment, number of on-demand

requests (if epidural PCA is being used), analgesic consumption,

BP, heart rate, respiratory rate and effort, level of sedation, urinary output, sensory and motor assessment (e.g., presence of

numbness or tingling, inability to raise legs or flex knees or

ankles), and a site and dressing check.

ADJUNCTIVE KETOROLAC USE

CASE 8-15, QUESTION 5: On the second postoperative

day, T.M. is able to rest comfortably when undisturbed

while receiving treatment with a lumbar epidural infusion

of hydromorphone 10 mcg/mL and bupivacaine 1.25 mg/mL

at a rate of 8 mL/hour. However, when he is moved at the

change of each nursing shift, he complains of significant

pain. Increasing the rate of his epidural infusion was tried,

but caused unacceptable pruritus and sedation. How can

T.M.’s intermittent pain needs be addressed?

The use of additional analgesics for breakthrough pain may

be necessary in patients receiving continuous epidural infusion.

T.M.’s intermittent pain could be managed by epidural PCA.

Like IV PCA, patient-activated epidural boluses can be administered to control pain during movement. Alternatively, injectable

ketorolac or acetaminophen may be considered for T.M.; these

agents do not contribute to respiratory depression, sedation, or

pruritus and can effectively treat moderate pain. The analgesic

effects of acetaminophen and NSAIDs are additive with the opioids and can lower postoperative pain scores. Patient selection

for ketorolac therapy should consider renal function, plasma

volume and electrolyte status, GI disease, risk of bleeding, and

concomitant drugs such as LMWH (which increases the risk

for bleeding and epidural hematoma). Acetaminophen is contraindicated in patients with severe hepatic impairment, severe

active liver disease, or known hypersensitivity to acetaminophen

or any excipient in the formulation. Acetaminophen should be

used with caution in patients with severe hypovolemia or severe

renal impairment.130

ADJUNCTIVE ANTICOAGULANT ADMINISTRATION

CASE 8-15, QUESTION 6: The surgeon has determined that

T.M. is at risk for developing postoperative venous thromboembolism. Enoxaparin 40 mg subcutaneously every day

has been ordered postoperatively. What are the risks of

enoxaparin in this situation? What are reasonable precautions?

Administration of an anticoagulant can increase the risk of

epidural or spinal hematoma formation, which can lead to longterm or permanent paralysis. Administration of antiplatelet or

anticoagulant drugs in combination with an anticoagulant (such

as an LMWH) results in an even greater risk of hemorrhagic

complications, including spinal hematoma. These findings have

led to concern for the safety of epidural analgesia in patients

receiving an LMWH. Important considerations for managing

a patient being administered an LMWH and receiving continuous epidural analgesia are (a) the time of catheter placement

and removal relative to the timing (and peak effect) of LMWH

administration and (b) whether the anticoagulant dose is low

(prophylactic dose) or high (treatment dose).131 For T.M., the

epidural catheter is already in place, and the LMWH is started

postoperatively as a single daily low (prophylactic) dose. It is safe

to leave the epidural catheter in place as long as the first dose of

LMWH is administered 6 to 8 hours postoperatively. The second

LMWH dose should be administered no sooner than 24 hours

after the first dose. The timing of the catheter removal is of the

utmost importance; it should be delayed for at least 12 hours after

the last dose of LMWH, with subsequent LMWH dosing to occur

a minimum of 2 hours after the catheter has been removed. The

risk of spinal hematoma is even greater when treatment doses

of LMWH are administered or if fondaparinux is selected as

the anticoagulant for deep vein thrombosis prophylaxis. In these

instances, the epidural catheter should be removed before the first

dose of LMWH or fondaparinux, and the first dose given at least

2 hours after catheter removal. Because T.M. is receiving prophylactic daily enoxaparin, his catheter should be removed no earlier

than 12 hours after his last dose of enoxaparin, with his next dose

administered no earlier than 2 hours after catheter removal.

MULTIMODAL PAIN MANAGEMENT

CASE 8-16

QUESTION 1: W.W., a 36-year-old man, arrives at the ambulatory surgery center for an inguinal hernia repair. This procedure will be performed under local anesthesia, with sedation as needed, and is expected to be completed within

TABLE 8-16

Comparison of Select Opioids for Perioperative Pain Management3,132–136

Property

Intravenous

Morphine

Intravenous

Hydromorphone

Intravenous

Fentanyl

Oral

Hydrocodone

Oral

Oxycodone

Onset 5 minutes ≤5 minutes ≤2 minutes 30–60 minutes 30–60 minutes

Peak effect 15–20 minutes 10–20 minutes 5–7 minutes 1–2 hours 1.5–2 hours

Duration 3–4 hours 2–3 hours 30–60 minutes 4–6 hours 3–4 hours

Approximate equianalgesic dose 2 mg 0.4 mg 25 mcg 5 mg 4 mg

173Perioperative Care Chapter 8

TABLE 8-17

Commonly Used Analgesic Drugs and Nonpharmacologic Techniques for Postoperative Pain Management105,106,132–136

Type of Agent Examples Potential Adverse Effects

Local anesthetics Tissue infiltration, wound instillation, peripheral

nerve block, epidural

Tingling, numbness, motor weakness,

hypotension, CNS and cardiac effects from

systemic absorption

NSAIDs Ketorolac (IV, IM, oral), ibuprofen (oral), naproxen

(oral), celecoxib (oral)

GI upset, edema, hypertension, dizziness,

drowsiness, GI bleeding, operative site bleeding

(not celecoxib)

Other nonopioids Acetaminophen (oral, intravenous, rectal) GI upset, hepatotoxicity, hypotension (IV

formulation)

Nonpharmacologic Ice or cold therapy Excessive vasoconstriction, skin irritation

Distraction, music, deep breathing for relaxation

Opioid combination products (oral) Hydrocodone + acetaminophen, oxycodone +

acetaminophen

Nausea, vomiting, pruritus, constipation, rash,

sedation, respiratory depression

Opioids Morphine (IV, epidural), hydromorphone (IV,

epidural), fentanyl (IV, epidural), oxycodone (oral)

Nausea, vomiting, pruritus, constipation, rash,

sedation, respiratory depression

CNS, central nervous system; GI, gastrointestinal; IM, intramuscular; IV, intravenous; NSAIDs, nonsteroidal anti-inflammatory drugs.

30 minutes. His medical and surgical histories are unremarkable. He is not currently taking any medication and

reports no drug allergies. After discharge from the ambulatory surgery center, how should W.W.’s postoperative pain

be managed?

In general, one expects that the greater the magnitude of the

surgical trauma, the greater the patient’s postoperative pain. For

minor surgical procedures (e.g., inguinal hernia repair, breast

biopsy), there is minimal surgical trauma, and the patient goes

home shortly after surgery. For intermediate surgical procedures

(e.g., total abdominal hysterectomy, laparoscopic cholecystectomy), short-term hospitalization is often necessary to observe

the patient’s recovery and to manage any pain. Patients undergoing major surgery (e.g., bowel resection, thoracotomy) experience a significant surgical stress response that can significantly

increase postoperative morbidity. Effective pain management is

essential, particularly in these patients.

If pain is mild in intensity, a nonopioid analgesic such as

acetaminophen or an NSAID is appropriate. If pain is moderate or severe in intensity or not controlled with acetaminophen

or an NSAID, an opioid is indicated. As previously discussed, the

agent, dose, and route are determined by the clinical scenario. If

the patient cannot take oral medications or a fast onset of action

is required to control pain, an IV opioid is indicated. Administration of an oral opioid and nonopioid combination product

will require a longer time before the patient will feel its analgesic effect. However, depending on the dose administered, the

anticipated degree of analgesia it will produce can be greater

than a lower dose of an IV opioid. One tablet of hydrocodone

10 mg plus acetaminophen 325 mg would be expected to provide greater and more long-lasting analgesia than one dose of

morphine 2 mg IV (Table 8-16).3,132–136 If a fixed combination of

opioid and nonopioid is used, the total daily dose administered

to the patient is limited by the maximum allowable daily dose of

the nonopioid (e.g., acetaminophen, ibuprofen).

Multimodal or balanced analgesia is often used to provide

postoperative analgesia. It can be difficult to optimize postoperative pain relief, to the point of achieving normal function, by

using one drug or route of administration. By using two or more

drugs that work at different points in the pain pathway, additive or

synergistic analgesia can be achieved and adverse effects reduced

because doses are lower and side effect profiles are different.

For an illustration that shows the sites of

action of the major drug classes used for pain

management, go to http://thepoint.

lwwcom/AT10e.

For perioperative pain management, combining acetaminophen with an NSAID provides superior analgesia than either

agent alone.137 Opioids are a mainstay of analgesic therapy for

moderate to severe pain. However, opioids are often associated

with intolerable adverse effects (e.g., nausea, vomiting, constipation, itching, sedation). Maximizing the use of nonopioid analgesics can result in less need for opioids and improved analgesia

(Table 8-17).105,106,136 When compared with morphine alone, the

addition of an NSAID after major surgery reduces pain intensity

and 24-hour morphine consumption, with a reduction in the incidence of morphine-related adverse effects of nausea, vomiting,

and sedation.133

For W.W., the anticipated surgical trauma is minor, and he will

recover at home. The surgeon will inject a long-acting local anesthetic (e.g., bupivacaine) into the tissues surrounding the surgical

incision. This will provide intraoperative anesthesia at the surgical site and postoperative analgesia until the effects of the bupivacaine wear off. Then, W.W. will likely require acetaminophen or

an NSAID for pain management. If his pain is not controlled, a

less potent opioid (e.g., hydrocodone) plus acetaminophen may

be used as a rescue analgesic.

KEY REFERENCES AND WEBSITES

A full list of references for this chapter can be found at

http://thepoint.lww.com/AT10e. Below are the key references

and websites for this chapter, with the corresponding reference

number in this chapter found in parentheses after the reference.

Key References

American College of Cardiology/American Heart Association

Task Force on Practice Guidelines et al. ACC/AHA focused

update on perioperative beta-blockade. J Am Coll Cardiol. 2009;

54:2102. (5)

174 Section 1 General Care

American Society of Anesthesiologists Task Force on Neuraxial Opioids et al. Practice guidelines for the prevention, detection, and management of respiratory depression associated with

neuraxial opioid administration. Anesthesiology. 2009;110:218.

(129)

Apfel CFC et al. A factorial trial of six interventions for prevention of postoperative nausea and vomiting. N Engl J Med.

2004;350:2441. (94)

Gan TJ et al. Society for Ambulatory Anesthesia guidelines for

the management of postoperative nausea and vomiting. Anesth

Analg. 2007;105:1615. (81)

Horlocker TT et al. Executive summary: regional anesthesia in

the patient receiving antithrombotic or thrombolytic therapy:

American Society of Regional Anesthesia and Pain Medicine

Evidence-Based Guidelines (Third Edition). Reg Anesth Pain Med.

2010;35:102. (131)

McCaffery M, Pasero C. Pain Assessment and Pharmacologic

Management. St. Louis, MO: Elsevier Mosby. 2011. (136)

Neal JM et al. ASRA Practice advisory on the treatment of local

anesthetic systemic toxicity. Reg Anesth Pain Med. 2010;35:152.

(43)

Pasero C. Assessment of sedation during opioid administration

for pain management. J Perianesth Nurs. 2009;24:186. (110)

Weiskopf RB, Eger EI 2nd. Comparing the costs of inhaled anesthetics. Anesthesiology. 1993;79:1413.

Key Websites

Lipid Rescue. Resuscitation for cardiac toxicity. http://www.

lipidrescue.org.

Malignant Hyperthermia Association of the United States.

http://www.mhaus.org.

San Diego Patient Safety Council. Tool Kit. Patient Controlled Analgesia (PCA) Guidelines of Care for the Opioid

Na¨ıve Patient. December 2009. http://www.chpso.org/meds/

pcatoolkit.pdf. (114)