Lecture 10 - Supportive Care II Flashcards
Why do cancer pts have pain?
cancer itself
invasion of disease into nerves - neuropathic pain; invasion of disease into organs - liver, brain metastases
surgery
treatment related - radiation, chemotherapy
Types of pain
many have combo of acute and chronic pain
Assessment of pain: OPQRSTU
O: what is the onset of pain
P: what provokes the pain
Q: what is the quality of pain
R: does the pain radiate
S: how severe is the pain
T: time of pain
U: understanding and impact
do you have other sx associated with pain?; are you having regular bowel movements?; what meds have you used in the past?; any med allergies?
Principles of pain management
understand the cause of pain
systematic approach consisting of: regular administration of around clock agents combined with PRN agents
individualized therapy; necessary to monitor for therapeutic and AEs; use lowest dose necessary
pain assessment is subjective
Level 1 pain: 2-3 on scale
non-opioid +/- adjuvant
Level 2 pain: 4-6 on scale
opioid for mild to moderate pain +/- non-opioid +/- adjuvant
Level 3 pain: 6-10 on scale
opioid for moderate to severe pain +/- non-opioid +/- adjuvant
Common pharmacologic options
opioids (~7-10)
combination products/mild opioids (~4-6)
non-opioids (~1-3)
Opioids
don’t have a max dose!
morphine, oxycodone, hydromorphone, fentanyl, methadone
Combination products/mild opioids
hydrocodone/acetaminophen
hydrocodone/ibuprofen
tramadol
codeine/acetaminophen
oxycodone/acetaminophen
oxycodone/aspirin
oxycodone/ibuprofen
have max dose b/c of tylenol and ibuprofen component
Non-opioids
acetaminophen
aspirin
ibuprofen
have max dose b/c of tylenol and ibuprofen component
Morphine
metabolized in liver to morphine-3-glucoronide, morphine-6-glucoronide, normorphine, and codeine; metabolites are excreted renally and will accumulate in renal insufficiency
use with caution in liver dysfunction
dosage forms: short and long-acting tabs, solutions, IV, PR
Hydromorphone
metabolized in liver to hydromorphone-3-glucoronide, 6-hydroxy metabolites; all renally excreted; give lower doses or longer dosing intervals in renal insufficiency
use with caution in liver dysfunction
dosage forms: short and long-acting tabs, solution, IV, PR
Oxycodone
metabolized by CYP2D6 to combo of conjugated and free oxycodone, nor-oxycodone, and oxymorphone
over sedation and CNS toxicity in renal failure pts
use with caution in liver dysfunction
dosage forms: short and long-acting tabs, solution, NO IV
Fentanyl
metabolized in liver primarily to nor-fentanyl
appears safe in renal dysfunction because no active metabolites are renally cleared, also safe in liver dysfunction
dosage forms: patch, IV, buccal, nasal spray, lozenges
great alternative in pts with: refractory N/V; head/neck/esophageal cancer pts who may not be able to maintain PO intake
Fentanyl REMS
risks of addiction, abuse, and misuse
respiratory depression
accidental exposure to duragesic
avoid direct external heat sources at application site
don’t start pt on patch if opioid naive
Methadone
consider for pts: with true morphine allergy, with opioid induced ADRs, with pain refractory to other opioids, with neuropathic pain, who need long-acting oral dosage form at low cost
avoid in pts with: numerous drug interactions, risks for syncope or arrhythmias, h/o unpredictable adherence, poor cognition
Methadone metabolites
are excreted in urine and feces
no AEs in pts with renal failure
NOT advised in severe liver dysfunction
very unpredictable half-life; risk of QT prolongation
Common toxicities of pain meds
constipation
sedation
N/V
pruritus
hallucinations
confusion/delirium
myoclonic jerking
respiratory depression
Managing constipation
always add bowel regimen when opioid therapy is initiated! - mild stimulant laxative/stool softener
pts do NOT develop tolerance to constipation!
Managing sedation
tolerance usually within a few days
hold sedative/anxiolytics
consider dosage reduction
Managing nausea/vomiting
change opioid
consider addition of sheduled anti-emetic therapy
Managing pruritus
most often seen with morphine
decrease dose or change opioid
consider addition of scheduled anti-histamine therapy such as diphenhydramine
Managing hallucinations
decrease dose or change opioid
consider adding neuroleptic med
Managing confusion/delirium
decrease dose or change opioid
consider adding neuroleptic med
Managing myoclonic jerking
may be sign of toxicity
consider changing opioid or treating underlying causes
Managing respiratory depression
sedation precedes respiratory depression
hold opioid
give low dose naloxone if on opioids for chronic pain
Different therapeutic options
patient controlled analgesia
celiac plexus block
intrathecal pain pump
radiation therapy
bisphosphonate therapy
Patient controlled analgesia (PCA)
pt demands +/- basal infusion of opioid with a lockout interval - pt can’t receive additional drugs more than the prescribed limits
pt must be awake + oriented to self administer; ONLY the pt can press the demand button
use with caution in pts with sleep apnea
pt in 1st 24 hrs after surgery have highest risk of over sedation and respiratory depression
Common PCA regimens in opioid-naive pts
use caution with continuous basal dosing initially for opioid naive pts
Adjusting PCA pumps
cut or stop basal rate when pt no longer needs it
if they have received multiple boluses, then increase basal rate
to assess total usage: total 24-hour dose (basal + # of hits used) to determine changes in therapy
Once PCA is controlled, how to change?
step 1: calculate 24 hour dose of current drug
step 2: convert to an equi-analgesic 24 hour dose of new agent using convesion chart
step 3: reduce dose by ~25% to account for incomplete cross-tolerance and titrate up
step 4: divide total 24 hour dose into appropriate dose
step 5: always add breakthrough PRN dosing, generally 10-20% of total 24-hour oral dose available q4h PRN (same drug is recommended)
Celiac plexus block
used commonly in patients with pancreatic cancer due to involvement of celiac plexus, which is a group of nerves that supply organs in abdomen
nerves are deactivated, pain relieved for 3-5 months
Intrathecal pain pump
used in pts refractory to opioids or increased toxicities - especially in pts who aren’t obtaining relief with elevated doses of opioid therapy
can use smaller doses of opioids when delivered intrathecally
tubing in CSF or spine deliver intrathecal meds - morphine, hydromorphone, fentanyl, clonidine, baclofen, ziconotide, bupivacaine
Radiation therapy commonly used in
painful bony metastases, brain metastases, spinal cord compression
Adjuvant pain therapy alternatives
dexamethasone, NSAIDs (work well for bony metastases
don’t treat anxiety/depression with opioids
Treatment planning for determining therapy
performance status
histology
staging
Performance status
activities of daily living
Karnofsky scale, eastern cooperative oncology group
Histology
tissue required for treatment
cell type and features indicating primary tumor site is essential
Staging
guides therapy and prognosis for a given tumor type
Evaluating response: RECIST criteria
response evaluation criteria in solid tumors
complete response: disappearance of all target lesions
partial response: 30% decrease in sum of longest diameter of target lesions
progressive disease = 20% increase in sum of longest diameter of target lesions
stable disease: small changes that don’t meet above criteria
Assessing toxicity
common toxicity criteria by cancer research groups
based on scale of 0-4 with 4 being most severe toxicity and 5=death
grade III and IV considered in phase I trials to determine dose limiting toxicity
