Exam 2 lecture 2 Flashcards
Why do cancer patients have pain?
cancer itself
invasion of disease into nerves (neuropathic pain)
Invasion into organs (liver and brain metastases)
Surgery
Treatment related (radiotherapy and chemotherapy)
Mnemonic used to assess pain in patients
OPQRSTU
What does OPQRSTU stand for
O- onset of pain
P- what PROVOKES pain
Q- Quality of pain
R- does the pain RADIATE
S- how SEVERE is the pain
T- TIME of pain
U- UNDERSTANDING and impact
What are some questions to ask to assess pain
Do you have other symptoms associated with pain?
Are you having irregular bowel movements?
What medications have you used in the past?
Medication allergies?
What are some patient specific factors that we use to determine proper analgesic
pain severity
medication access
hepatic/renal function
previous analgesic therapy
What are some medication specific factors that we use to determine proper analgesic
ROA
Duration of action/dosing frequency
potency
side effects
drug drug i/a
cost
What are some common pharmacologic options for each pain scale (7-10, 4-6, 1-3)
7-10= morphine, hydromorphone, oxycodone, fentanyl
4-6=hydrocodone/acetaminophen, oxycodone/acetaminophen, hydrocodone/ibuprofen, oxycodone/aspirin, tramadol
1-3= acetaminophen, aspirin, ibuprofen
What is morphine metabolized into and where is it metabolized? How is it excreted? When to use with caution?
Metabolized in liver to morphine-3-glucoronide, morphine-6-glucoronide, normorphine and codeine.
Metabolites excreted renally (will accumulate in renal insufficiency)
Use with caution in liver dysfunction
What is hydrmorphone metabolized into? Where is it metabolized? How is it excreted? When to use with caution?
Metabolized in liver to hydromorphone-3-glucoronide. All renally excreted. (lower dose or increase interval in renal insufficiecy)
Use in caution with liver dysfunction.
What is oxycodone metabolized by? WHat is it metabolized into? What is seen in renal failure patients? WHen to use with caution?
Metabolized by CYP2D6
Metabolized to a combination of nor-oxycodone and oxycodone
Over sedation and CNS toxicity reported in renal failure patients
Use with caution in liver dysfunction
Where is fentanyl metbolized? What is it metabolized to? Can we use in liver dysfunction? Can we use in renal dysfunction?
Metabolized in liver to nor-fentanyl. Safe to use in renal dysfunction. (no active metabolites are renally cleared.) Also safe in liver dysfunction.
Fentanyl is a great alternative in what kind of patients.
-Refractory N/V
-Head/neck/esophageal cancer -patients who may not be able to maintain adequate PO intake
blackbox warning on fentanyl
Respiratory depression may occur.
What type of patients do we consider methadone in?
- True morphine allergy
- With opioid induced ADR
- With pain refractory to other opioids
-with neuropathic pain
What type of patients to avoid methadone in?
-history of unpredictable adherence
-poor cognition
- risk for syncope or arrhythmias
- numerous drug i/a
How is methadone excreted? Methadone in renal failure? What about liver failure?
Metabolites excreted in urine and feces.
No reported adverse effects with renal failure patients.
Not advised in patients with severe liver dysfunction
Half life and adverse effect of methadone
T1/2 is very unpredictable (8-59 hrs)
- Risk of QT prolongation (assess other meds)
What are some common toxicities associated with opioids
Constipation
sedation
nausea/vomiting
pruritis
hallucinations
confusion/delirium
myoclonic jerking
respiratory depression
How to handle constipation and sedation associated with opioid use
Constipation- ALWAYS ADD A BOWEL REGIMEN.
sedation- tolerance develops within a few days. Hold sedatives and/or anxiolytics. Consider dose reduction
How to handle N/V that comes with opioid use
change opioid
consider addition of scheduled anti emetic therapy (metoclopramide or prochlorperazine)
This is a transient side effect that resolves in 7-10 days
how to handle pruritis and hallucinations associated with opioid use
pruritis- Most often seen with morphine. Decrease dose or change opioid. consider addition of antihistamine like diphenhydramine
hallucinations- decrease dose or change opioid. Consider addition of neuroleptic medication to regimen
how to handle confusion/delirium and myoclonic jerking associated with opioid use
Confusion/delirium- decrease dose or change opioid
myoclonic jerking- May be a sign of toxicity. consider changing opioid or treating underlying causes
how to handle respiratory depression that occurs with opioid use
-sedation precedes respiratory depression.
-hold opioid
-give low dose naloxone (not pure naloxone, patient will be in excruciating pain. dilute 1 ml naloxone and 9 ml NaCl)
what are some different therapeutic options for pain
Patient controlled analgesia
Celiac plexus block
intrathecal pain pump
radiation therapy
bisphosphonate therapy
When to use PCA with caution (patient controlled analgesia). Which patients have highest risk of over sedation and respiratory depression on PCA?
Use with caution in patients with sleep apnea. Patients in first 24 hours after surgery have the highest risk of over sedation and respiratory sedation
how to change PCA to a new agent (dose conversion) step wise
- calculate 24 hour dose of current drug
- convert to equi analgesic 24 hr dose of new agent using conversion chart
- reduce dose by 25% to account for incomplete cross tolerance
- divide total 24 hr dose into appropriate dose
- Always add breakthrough PRN dosing, generally 10-20% of total 24 hour oral dose available every 4 hrs. PRN if oral. (same drug is recommended. long acting-morphine and IR morphine as needed)
define celiac plexus block
Used commonly in pts with pancreatic cancer due to involvement of celiac plexus. Celiac plexus are a group of nerves that supply organs in the abdomen
When are intrathecal pumps used? How dose the dosing change?
Used in patients who are refractory to other opioid therapy or increased toxicities.
used in pts who are not obtaining relief with elevated doses of opioid therapy
used in pts who have more toxicities than benefit from traditional opioid therapy
used much smaller doses of opioids as delivered intrathecally
What are commonly sed intrathecal medications
Morphine
hydromorphone
fentanyl
clonidine
baclofen
ziconotide
typical intrathecal dose range
0.2-1 mg/day
what are adjuvant pain therapy alternatives
dexamethasone
NSAIDs
ECOG performance status (PS) grading
0= fully active, able to carry on all pre-disease performance without restriction.
1= restricted in physically strenous activity, but ambulatory and able to carry out work of a light and sedentary nature
2= Ambulatory and capable of all self care, but unable to carry out any work activities.
3= capable of only limited self care, confined to bed
4= completely disabled
5= dead
RECIST criteria definition
Complete response (CR)= disappearance of all target lesions
partial response (PR)= 30% decrease in the sum of the longest diameter of target lesion.
progressive disease (PD)= 20% increase in the sum of the longest diameter of target lesions
Preceptor asks you about colony stimulating factors for prevention of neutropenic fever and use specifically in a patient with breast cancer who is to receive chemotherapy with docetaxel, doxorubicin and cyclophosphamide. SHould this pt receive CSF upfront as primary prophylaxis?
Yes the patient should receive CSF.
We do primary prophylaxis when regimen has more than a 20% chance of causing neutropenia.
CSF prevents that. If we do not use CSF and the patient gets neutropenic fever, we use CSF a second time around (secondary prophylaxis)
Filgrastim and peg-filgrastim difference is peg filgastrim is a one time flat dose.
Patient admitted to hospital with chemo induced mucositis. Patient has anal cancer and received 5-FU over 96 hours, seven days ago. SM complains that he has been unable to tolerate foods and rates pain 9 out of 10. What therapies do you recommend to the resident.
5 FU has a high risk of causing oral mucositis.
IV pain meds or PCA might be an option. He is in too much pain, fent patch takes time to kick in.
Lidocaine mouthwashes
do ice chips (cryotherapy)
dose reduce 5FU next time
65 year old male with NSCLC. He has received 3 cycles of chemo consisting on aclitaxel, carboplatin and is coming for 4th cycle.WBC count and platele are WNL. His hemoglobin has steadily dropped from 11 to 9. You ask your preceptor about using ESAs. What answer would he give you? Should pt receive ESA.
Is this curative intent is the 1st question we need to ask. If we are giving chemo with a curative intent, we do not use ESA.
We need to get iron studies. Low iron wont work.
Transfusion works quicker and would be better in this case.
Are they symptomatic? actively bleeding? We would do transfusion instead of ESA.
