Exam 2 Flashcards
What is the mechanism of nausea and vomiting in oncology patients?
Cytotoxic chemotherapy damages the epithelial cells in the lining of the GI tract. Enterochromaffin cells that line the GI tract contain large stores of serotonin, which is then released in massive quantities after chemo. (serotonin, dopamine, acetylcholine, and substance P are all neurotransmitters that are targets)
The chemoreceptor trigger zone (CTZ) stimulates the vomiting center (medulla stimulates the emetic response).
- Nausea: feeling like you have to vomit
- Wretching: labored movement of abdominal/thoracic muscles before vomiting
- Vomiting: ejection or forced expulsion of gastric contents through the mouth
What are the 5 types of N/V associated with cancer patients?
Anticipatory - learned response due to N/V from prior cycles of chemo
Acute - emetic response w/in 24h of chemotherapy
Delayed - emetic following >24h after completion of chemo, mechanism not fully understood, but may involve substance P binding to neurokinin 1 receptor
Breakthrough - N/V occurring even when patient takes antiemetics
Refractory - N/V that persists despite appropriate antiemetics
Who is at risk for CINV?
- Women > Men
- Younger > Older
- Prior history of motion sickness
- Previous history of morning sickness
- Previous CINV
- Anxiety/high pretreatment anticipation of nausea
What is Regimen A for Highly Emetogenic chemotherapies?
4 drug regimen given right before chemo:
1. NK-1 antagonist: aprepitant, fosprepitant, polapitant, netupitant, posnetupitant
2. Steroid: dexamethasone
3. 5-HT3 antagonist: dolasetron, granisetron, ondansetron, palonosetron
4. Atypical antipsychotic: olanzapine
*NK-1 antagonist & steroid are both really good for acute AND delayed, 5-HT3 antagonist is better for acute (not as much delayed)
*can add lorazepam or H2RA/PPI if needed (to any regimen or emetogenicity)
What is Regimen B for Highly Emetogenic chemotherapies?
3 drug regimen given right before chemo:
1. Atypical antipsychotic: Olanzapine
2. 5-HT3 antagonist: Palonosetron
3. Steroid: Dexamethasone
What is Regimen C for Highly Emetogenic chemotherapies?
3 drug regimen given right before chemo:
1. NK-1 antagonist: Aprepitant, fosprepitant, polapitant, netupitant, posnetupitant
2. 5-HT3 antagonist: Dolasetron, granisetron, ondansetron, palonosetron
3. Steroid: Dexamethasone
What is Regimen A for Moderately Emetogenic chemotherapies?
2 drug regimen:
1. Steroid: Dexamethasone
2. 5HT3 antagonist: Dolasetron, granisetron, ondansetron, palonosetron
What is Regimen B for Moderately Emetogenic chemotherapies?
- Atypical antipsychotic: Olanzapine
- 5-HT3 antagonist: Palonosetron
- Steroid: Dexamethasone
What is Regimen C for Moderately Emetogenic chemotherapies?
3 drug regimen given right before chemo:
1. NK-1 antagonist: Aprepitant, fosprepitant, polapitant, netupitant, posnetupitant
2. 5-HT3 antagonist: Dolasetron, granisetron, ondansetron, palonosetron
3. Steroid: Dexamethasone
What is the regimen for Low Emetogenic chemotherapies?
Only need 1 drug:
- Dexamethosone
- Metoclopramide
- Prochlorperazine
- 5HT3 antagonist (dolasetron, granisetron, ondansetron)
*can also add lorazepam or H2RA/PPI if needed (just like the other ones)
What can we give for breakthrough nausea and vomiting for CINV?
To take home in case they have N/V after they leave the clinic.
*Want to chose something different from what they just had in clinic.
- Dopamine receptor antagonists (haloperidol, metoclopramide)
- Phenothiazines (prochlorperazine, promethazine)
- Antypsychotic (olanzapine)
- Benzodiazepine (lorazepam)
- Cannabinoids (dronabinol, nabilone)
- Serotonin antagonists (dolastreon, ondansetron, granisetron)
- Steroids (dexamethasone)
- Anticholinergic (scopolamine)
What can we give for delayed CINV?
Typically involves use of one of the following: dexamethasone, NK-1 antagonist, olanzapine
What can we give for anticipatory nausea and vomiting (CINV)?
- Prevent it (use antiemetic therapy during every cycle of treatment)
- Behavioral interventions (hypnosis, exercise, etc.)
- Acupuncture
- Lorazepam
What are the common toxicities of the agents we use to prevent CINV?
5HT3 antagonists - headache, constipation, QTc prolongation
Corticosteroids - anxiety, insomnia, hyperglycemia
Substance P antagonists (NK1 antagonists) - hiccups, drug interactions
Dopamine antagonists - extrapyramidal side effects, diarrhea, sedation
What is the pathophysiology of mucositis and how do you treat/prevent it?
Muscositis can range from mild inflammation to bleeding ulcerations. It can be described as initiation, upregulation with generation of messengers, signaling and amplification, ulceration, then healing. It normally progresses in a step wise fashion in parallel with the patient’s nadir (lowest point the pt’s WBC count goes after chemo).
Prevention: avoid rough foods, salty/acidic foods; eat soft or liquid foods; avoid smoking and alcohol
Pain management: Topical anesthetics (lidocaine, diphenhydramine, etc.); oral cryotherapy (ice), oral and parenteral opioid analgesics
How do you prevent and treat neutropenia associated with chemotherapy use?
*always check blood counts before chemo (WBC, platelets, RBC)
- low WBC -> infections, low platelets -> bleeding, low RBC -> fatigue
- Generally, nadir occurs 10-14 days after chemo then the counts recover by 3-4 days
Prophylaxis: Use colony stimulating factors (CSFs)! Given after chemo
- filgrastim, pefligrastim (more expensive and longer 1/2 life), biosimilars
Primary Prophylaxis:
- given to pts who have a chemotherapy regimen that is expected to cause ≥20% incidence of febrile neutropenia
- high risk patients that had/have pre-existing neutropenia, extensive prior chemotherapy, or previous irradiation or the pelvis or other areas containing large amounts of bone marrow
Secondary prophylaxis:
- given to patients who have experienced neutropenic episode previously
How do we approach thrombocytopenia and anemia in chemotherapy patients?
Thrombocytopenia:
Always looks at platelet count. A lot of times, people can live with low platelets, but if the pt needs platelets, we will give them platelets.
Anemia:
When the Hgb drops under 11, evaluate the causes of anemia. Should transfuse the patient if symptomatic (ex. SOB, heard time moving around). We can use iron and consider use of erythropoietic stimulating agents (ESA - don’t use these much anymore).
- ESAs not recommended if pt is receiving myelosuppressive chemo w/ curative intent, if they are not receiving chemo, if they are receiving non-myelosuppressive chemo.
- Consider ESA use in pts with cancer and CKD, pts undergoing palliative chemotherapy, pts without other identifiable causes.
What are the common toxicities that are associated with chemotherapeutic agents and how do we manage them? (5 toxicites)
Myalgias/Arthralgias: (taxanes, aromatase inhibitors, exemestane)
- Treat with NSAIDS (maybe opioids)
Hemorrhagic cystitis: (cyclophosphamide, ifosfamide)
- Treat with hydration (prevention) and Mesna (prevent)
Heart Failure: (anthracyclines, HER2 therapies (trastuzumab), cyclophosphamide)
- Monitor cumulative dose, assess for risk factors, and use Dexrazoxane
Peripheral neuropathy: (taxanes, vinca alkaloids, platinums)
- Treat by changing infusion rate (paclitaxel) and using adjunctive pain meds (ex. gabapentin, amitriptyline)
Pulmonary toxicities: bleomycin
- Treat with corticosteroids
What are the differences in cardiotoxicity from chemotherapeutic agents? (acute, chronic, vs. late onset)
Caused by the formation of iron-dependent oxygen free radicals due to stable anthracycline-iron complexes, which cause electron transfers
- There are low levels of enzymes in the heart that can break down the free radicals.
- This damage is irreversible
Acute: occurs immediately after single dose or course of therapy with an anthracycline.
- Uncommon, transient
Chronic: onset w/in a year of receiving anthracycline therapy
- Common & life-threatening, related to cumulative dose the pt received
Late-onset: develops several years or decades after therapy
- manifests as ventricular dysfunction, CHF, conduction disturbances, arrhythmias
- more often in childhood/adolescent cancer survivors
What is different between anthracyclines and HER2 inhibitors in regard to cardiotoxicity? Can you use the HER2 inhibitor again if it causes cardiotoxicity?
Trastuzumab: REVERSIBLE
- mechanism involves EGFR pathway, which blunts the effects of stress signaling pathways that are required to maintain cardiac function.
- In the case of toxicity, stop the drug & wait for it to go back to normal, then you can restart
Anthracyclines - IRREVERSIBLE
Why do patients with cancer have pain?
- The cancer itself
- The cancer may invade into nerves, causing neuropathic pain
- Disease can invade into organs, such as liver mets or brain mets
- Surgery
- Treatment related, such as radiation or chemotherapy
How do we assess pain?
OPQRSTU:
- O: onset of pain
- P: what provokes the pain
- Q: quality of pain
- R: does the pain radiate
- S: how severe is the pain (0-10)
- T: time of pain
- U: understanding of what is happening/expectations
- Do you have other symptoms associated with pain
- Regular bowel movements?
- What medications have you used in the past?
- Any medication allergies?
How do we make a treatment plan for pain management based on patient specific factors?
We need to understand the cause of the pain, combine maintenance meds with PRN therapies, recognize pain treatment is based on the individual, monitor therapeutics/adverse effects, use the lowest doses necessary.
Patient specific factors: pain severity, medication access, hepatic/renal function, previous analgesic therapy
- non-opioid +/- adjuvant
- opioid for mild-mod pain +/- non-opioid +/- adjuvant
- opioid for mod-severe pain +/- non-opioid +/- adjuvant
What are the non-opioid, combo/mild opioid, and opioid products we have for pain? What are the important max doses?
non-opioids (pain 1-3): APAP (4g max), ibuprofen (3200mg max), aspirin
combo products/mild opioids (pain 4-6): hydrocodone/APAP, oxycodone/APAP, tramadol, codeine/APAP, etc.
- max dose based on either APAP or ibuprofen
opioid (7-10): morphine (most common), hydromorphone, oxycodone, fentanyl, methadone
- max dose to respiratory depression