Patients often worry about the safety of PCA, which can lead
to reluctance to provide themselves with adequate pain relief.
J.A. should be informed that she will be frequently assessed by
the nurse (particularly during the first 24 hours of therapy). If she
becomes sleepy from the opioid, she should not press the button.
When this adverse effect of the opioid has worn off, she will wake
of the opioid if she has pain. This is an important safety feature of
PCA and is the reason family members must not push the button
for the patient. However, J.A. should also know that she may have
to press the button several times (after the lock-out interval has
passed) before her pain is relieved. She must also be informed
that she may require a larger PCA dose, so it is important for
J.A. to assess her pain relief from her current (“usual”) dose that
most patients are initially started on after surgery. Accurate pain
assessment after her prescribed dose is critical for ensuring that
her dose is sufficient to provide the desired level of analgesia. She
should also understand the possible adverse effects of her PCA
medication and what can be done to prevent and treat these
told of the negligible risk of narcotic addiction from short-term
PCA use and be given ample opportunity to ask questions.
CASE 8-14, QUESTION 4: Meperidine is ordered for J.A.’s
PCA. Is this a reasonable drug choice for her?
Ideally, opioids for PCA administration have a rapid onset and
with the drug selected for PCA. Morphine is by far the most
on past patient experiences, allergies, adverse effects, and special
of CNS toxicity from normeperidine include agitation, shaky
is administered in higher doses or for a prolonged period.111
reuptake and has a fairly high serotonergic potential. The risk
of a patient developing the serotonin syndrome is greater when
paroxetine, venlafaxine).112 For these reasons, meperidine is a
in hepatic and extrahepatic sites (particularly the kidney) to its
urine. Morphine-6-glucuronide is an active metabolite that can
accumulate in patients with renal failure, resulting in prolonged
analgesia, sedation, and respiratory depression.113 Because of
169Perioperative Care Chapter 8
Adult Analgesic Dosing Recommendations for Intravenous Patient-Controlled Analgesiaa,102,114,115
Drug Usual Concentration Usual Range Lock-Out Interval (minutes)
Fentanyl (as citrate) 10 mcg/mL 0.01–0.02 0.01–0.04 10
Hydromorphone hydrochloride 0.2 mg/mL 0.2–0.3 0.1–0.4 10
Morphine sulfate 1 mg/mL 1–2 0.5–2.5 10
adjusted because of age, condition of the patient, and prior opioid use.
J.A.’s diminished renal function, morphine should probably be
avoided because other options exist. Hydromorphone is not
metabolized to an active 6-glucuronide metabolite, and fentanyl
is metabolized to inactive metabolites. Either hydromorphone
intervals for drugs administered by PCA.102,114,115
hydromorphone and what lock-out interval should be used
for her initial PCA pump settings?
If J.A. is experiencing pain before PCA has been initiated,
she should receive a loading dose of IV hydromorphone titrated
to achieve baseline pain relief (may require up to 1 mg). Once
adequate analgesia is achieved, demand doses of 0.2 mg with
a lock-out interval of 10 minutes would be a good choice to
maintain analgesia for this opioid-na¨ıve patient. If J.A.’s pain is
not relieved after two to three demand doses within 1 hour, the
demand dose can be increased to 0.3 mg.
CASE 8-14, QUESTION 6: After the first postoperative
evening, J.A. tells you that she had a terrible time sleeping.
She describes waking up in pain frequently, despite pressing
the history on her PCA device reveals successful delivery of
9 mg of hydromorphone (30 demand doses, 0.3 mg each)
during the past 12 hours. J.A. is not sedated and reports no
adverse effects from hydromorphone. How can J.A.’s pain
(continuous) infusion has not been shown to improve analgesia
basal (continuous) infusion of opioids cannot be recommended
for acute pain management. In an opioid-na¨ıve patient such as
J.A., however, continuing to increase the demand dose increases
the risk of excessive sedation and respiratory depression (owing
to high peak levels). Also, J.A. describes her pain as moderate to
severe in intensity and fairly constant in nature when she does not
regularly push the demand button. For J.A., a continuous infusion
could be beneficial. As a rule of thumb, an opioid-na¨ıve patient
experiencing acute pain (that can change quickly) should receive
equivalent, which would be 0.2 mg/hour for hydromorphone).
For J.A., a continuous infusion of 0.2 mg/hour hydromorphone
should be initiated in addition to her demand dose of 0.3 mg
every 8 minutes. Because the onset of action of hydromorphone
is about 5 minutes and the peak effect occurs in 10 to 20 minutes,
shortening the lock-out interval is not recommended because
J.A. could access the next dose of hydromorphone before the
effects of the initial dose can be appreciated. That could lead to
dose-stacking and significant adverse effects, such as excessive
sedation and respiratory depression.
CASE 8-14, QUESTION 7: The next day, J.A. requested only
a few demand doses and reports adequate pain relief with
her PCA, but now complains of feeling slightly groggy and
morning. What are the adverse effects of PCA opioids, and
how can J.A.’s complaints be addressed?
These adverse effects can be managed by dose adjustments or
2 hours during the first 24 hours of therapy). The patient should
status.110,114 Particular attention must be paid to patients at high
risk for respiratory depression from an opioid. These risk factors
include age older than 65 years, obesity, pulmonary disease or
other conditions that reduce ventilatory capacity, and known or
suspected history of sleep apnea.114 Technical problems must also
be ruled out. The PCA pump should be checked to ensure that it
is delivering the correct drug and dose, programming should be
checked for accuracy (e.g., drug concentration, dosing interval),
BP, heart rate, respiratory rate and effort, and level of sedation,
as well as the presence of other adverse effects of opioids such as
J.A.’s PCA hydromorphone dose could be reduced to manage
her sedation and nausea. However, her pain control must be
carefully reassessed to ensure efficacy of the newly lowered dose.
An order for a nonsedating antiemetic (such as ondansetron)
could also be provided. NSAIDs (ketorolac IV or other NSAID
orally) or acetaminophen (IV or oral) are not sedating; thus, they
should be added to the analgesic regimen to provide analgesia and
allow a reduction in her opioid dose. However, because of J.A.’s
compromised renal function, acetaminophen is a better choice
than an NSAID. If J.A. is able to take fluids orally, PCA should
be discontinued and oral analgesics administered as needed. As
healing occurs, her pain intensity should lessen, and oral opioid–
acetaminophen products should manage her pain adequately.
resection, urethral stents, ileorectal pull-through). His pain
is managed through a lumbar epidural catheter. What are
the benefits and risks of epidural analgesia, and why was
this approach to postoperative analgesia chosen for T.M.?
Epidural analgesia can offer superior pain relief compared with
traditional parenteral (IM, IV, and IV PCA) analgesia116 as well as
(including IV PCA) because it allows individualization of the
analgesic requirements, lower total drug use, greater patient
satisfaction,119 and improved analgesia.120 Epidural catheter
insertion site inflammation or infection, catheter migration, and,
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