Tag: Oncology

ADS – Electrolytes

I always felt from undergrad that electrolytes as a topic was some sort of nebulous concept… your patient has low potassium, so what are you gonna do? Replace it of course! Also, in the renal elective we got a run-down of hypo and hyperkalemia, derangements in acid/base balance (including anion and non-anion gap acidosis), but this ADS dove a bit deeper into how all those parameters interplay with each other. Some take-home messages I got:
– Digoxin and electrolyte balance are quite closely interrelated. Basically you need extracellular potassium to work the pump, and you need magnesium as a cofactor for the pump. Digoxin binds to that pump. Less K = more dig can bind = less Na-K pump activity.
– Low Mg can result in low K, Na, PO4, and low Ca. In other words – no matter what you do, replace the magnesium along with the others.
– I finally learned what “refeeding syndrome” actually means. I encountered a couple of cases on my Oncology rotation, but never grasped the mechanism behind it. Basically if you are in a ketogenic state and making your carbs from ketones and free fatty acid breakdown (>72 hrs after your last bite of food), if you aggressively refeed the patient, glycolysis intermediates contain phosphorylated compounds, which need phosphate —> high demand = low PO4.

I also enjoyed the cases, as they allowed us to put everything together. I can now appreciate the importance of the magnesium, and can confidently recommend replenishment strategies (after memorizing a couple of products and doses!)

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Reflections on Oncology

Hey, that wasn’t so bad now, was it? First clinical rotation complete! I think I am starting to fully understand what previous residents say – as soon as you start feeling somewhat comfortable with a ward, it’s time to move on to the next rotation. However, it is all to make you a more adaptable and proficient clinician. I thoroughly enjoyed my time at BCCA, and I had so many great opportunities, such as to observe procedures such as lumbar punctures and bone marrow biopsies, and take a trip down to RadOnc to see the machines and learn more about radiation-specific adverse effects.

I also became more comfortable with formulating medical problem and DTP lists and prioritizing them. I think overall, I never expected to be an expert in oncology by the end of it, but I think I met my overarching goal which was to “become marginally closer to being a competent clinician” – yay for achieving things! How about my goals that I came up with before the rotation?

Goal #1: Develop a head to toe approach to assessing a patient for adverse drug events secondary to chemotherapy, or supportive agents for chemotherapy – yes, did this. Went back to my review of systems, and my preceptor helped me work through the laundry list of side effects that one may experience, depending on the chemotherapy agent that is being used, and at which dose.

Goal #2: Be able to provide executable recommendations upon demand for proactive nausea and vomiting management based on the BCCA protocol the patient is on – achieved this. I had a patient in my last week with a pancreas primary that was locally advanced to her GI system who had intractable nausea and vomiting, but unfortunately was non-compliant to diet restrictions recommended by the RD. It was very tricky discerning which medications or non-pharm measures were actually effective for her, but it was rewarding working with the Pain and Symptom medical team, even if it was brainstorming medication regimens that we hadn’t tried with her. My roadmap going forward will be to go back to the fundamentals – have an alternatives list to every recommendation – then you won’t miss anything.

Goal #3: Develop a process for counselling oncology patients on either a new chemotherapy regimen or supportive care medications – I did prepare a medication calendar for a couple of patients during the course of the rotation, and counselled on changes to therapy, and also symptoms of oncologic emergencies to watch out for, such as fever (heralding febrile neutropenia), or bilteral numbing in extremities (heralding spinal cord compression). Most of the patients I came across were already midway or further through their treatment regimen.

Back from the Sunshine Coast and enjoying my vacation week so far – Gen Med next…

C3.5 R2: Prepare and deliver educational seminar to pharmacists (#1)

On August 30th, I delivered a case presentation around a topic that is commonly encountered by the clinical pharmacist in an oncology setting – non-painful chemotherapy-induced peripheral neuropathy (CIPN). As quite a number of patients on the ward I was on were receiving platinum agents or vincristine, I encountered it in every single of those patients as well. It triggered a clinical question in me that I sought to answer – is there anything that I could recommend to help these individuals, and when would I recommend it?

Perhaps not surprisingly, most of the evidence for treatment of CIPN is centered around either painful CIPN, or extrapolated from evidence in non-chemotherapy induced peripheral neuropathy of other etiologies, such as diabetes.

Here are the things that I thought went well:
– I think that my literature search was sound and thorough
– I was able to fully rationalize my decision-making after some prompting by questioning after the presentation
– I felt at ease delivering the presentation

Here are things that I would like to work on for my next seminar:
– I say “uh” at lot. I think I just need to pause at certain places to gather my thoughts.
– Don’t go fidgeting for answers during question period
– Be a more effective pharmacist by anticipating next steps after this therapeutic decision: what if this doesn’t work? How long to treat?

Upon the advice of Dr. Abadi, this may turn into a publishable case study that I will continue to keep in touch with my primary preceptor, and follow-up on this patient’s response to therapy. I also, depending on the patient’s response and follow-up, may turn this into a BC-wide case presentation (after some serious cutting – 20 minutes is short!)

Here are my slides: Oncology Case Presentation

C3.2 R5: Submit an ADR report to appropriate authority

On my oncology rotation, I came across a patient that I was taking care of who was admitted for hypoxia and SOB when she reported for assessment before her next cycle of chemotherapy for metastatic breast cancer. She was dyspneic, exhausted, and was saturating 89% on room air. She had already received multiple rounds of chemo, including first-line and salvage therapy; unfortunately they have proven not effective. Her chemo drugs were:
– Everolimus 10 mg PO daily
– Exemestane 25 mg PO daily

The medical team decided to treat her for a pneumonia with moxifloxacin 400 mg PO daily for a week based on her signs and symptoms, given initial CXR revealed opacity in the RLL. The timeframe of which she presented with these symptoms was on the scale of weeks, rather than days.

Unfortunately she continued to be dyspneic after the course of antibiotics, and a subsequent CT head and chest revealed ground glass lesions that were suggestive of pneumonitis. A course of prednisone for 9 days has failed to afford much benefit as she still requires 4L of supplemental oxygen on nasal prongs.

As this was a severe adverse effect associated with everolimus, I thought it would be valuable to report it to Health Canada.

C3.1 R4(h): Provide continuity of care from in-hospital to outpatient setting (#1)

Patients at BCCA often require submissions to Special Authority and other mechanisms (such as drug company-sponsored coverage) because supportive medications are not covered by the Agency. I am involved with discharge prescription and medication calendar planning for the patients under my care, but I wanted to highlight a special case.

This is a 29 year old woman with Ewing’s sarcoma, undergoing (overall) her 25th cycle of chemotherapy (salvage therapy with possibly curative intent). As she has unfortunately suffered an episode of febrile neutropenia in the past, she qualifies for Special Authority for filgrastim for secondary prophylaxis. I submitted the request on behalf of the attending physician, and also provided the following:
– Submission of request to ANSWERS 3rd party program for any additional coverage in case the pt had not met her Pharmacare deductible
– Liaison with the community pharmacy to ensure adequate stock was available
– She also was interested in use of various NHPs with her chemotherapy: counselled that use of vitamin B12 had no concerns but the other supplement (a proprietary blend of mushroom extracts) would be ill-advised
– Counselling to call the BCCA immediately at any sign of fever or “feeling off”, as not all neutropenic patients can mount a fever.

C3.2 R5: Reconcile a patient’s medications on ADMISSION (#1)

Today there was a new admission to the ward. This was a good example of gathering information that was necessary for a MedRec but not necessarily having the complete info that would be gathered from, say, a workup. This patient was in for nausea and vomiting, and drainage of a pleural effusion. She received her most recent cycle of BRAVGEMP 4 days ago. There were a few things to reconcile from the information on Pharmanet:
– She was taking atenolol 50 mg daily, not 25 mg daily
– She was applying fentanyl 12 mcg/h, one patch q72h, not 1/2 patch day 1, then the other 1/2 patch 24 hrs later as it appeared on Pharmanet (this was a titrating regimen she had completed a while ago)
– She was no longer taking escitalopram and nifedipine, even though it did show it was filled 3 months ago for a 3 month supply.
– She was taking extended-release dimenhydrinate QHS (patient’s own medications) with good effect for nausea.

Overall this highlighted for me how important it is to not simply blindly trust Pharmanet as an accurate source of medication information. It also allowed me the opportunity to collaborate with the physician in reconciling the orders.

C3.2 R5: Reconcile a patient’s medications on DISCHARGE (#1)

During my first week I had the opportunity to help take care of a patient (65 yo female) who was in for treatment of double-hit diffuse large B-cell lymphoma. During her admission, there were a few changes to her medication, in addition to adherence concerns as she missed a week of her SMX/TMP for PCP prophylaxis as there was confusion regarding blister packing. I made the following changes to her medications in collaboration with the doctor:
– Discontinued her ASA 81 mg PO daily that she was taking for primary CV prevention. She had a Hx of mitral valve prolapse, but in the absence of HF, A-fib or previous MI/stroke, there was no compelling indication.
– Increased her valacyclovir to 500 mg PO BID from PO daily as she was seropositive for HSV and suffered from an especially bad bout of mucositis (that was HSV-positive on swab) last cycle. The BID dose is usually for HIV-positive patients or leukemia patients, but given her aggressive regimen (daEPOCH-R), the doctor and I felt it prudent to increase the dose, also considering valacyclovir’s favourable safety profile.
– Increased her gabapentin from 600 mg PO QHS, adding 100 mg PO with breakfast and lunch, titrating q week to a target of 600 mg PO TID for fibromyalgia. There was a patient teaching point as well as I explained to her that one would develop tolerance to sedation as gabapentin is slowly titrated.

I made a med calendar for her, had her medications blister packed, prepared her discharge prescriptions, and explained the changes we made in hospital. What I hope to improve upon and apply in future is becoming more efficient with coordinating with the community pharmacy such that medications are delivered in good time when the patient goes home.

Nuggets of Knowledge – when is Pneumocystis pneumonia prophylaxis warranted in a non-HIV infected patient?

I notice that quite a few of the patients I have encountered so far in Clinical Orientation and my 1st patient on my Oncology rotation are on SMX/TMP for PCP prophylaxis. It begged the question: when is it warranted? According to this meta-analysis, if the risk is >6%, you give prophylaxis. Which conditions warrant this type of risk? Should all cancer patients receive it?

– Cancer patients who SHOULD receive PCP prophylaxis: HL, NHL, brain tumours, myelodysplasia, ALL, lymphoproliferative dz, or myeloma, relapsed dz, “high-dose” corticosteroids, or R-CHOP-14 regimen
– Treatment with 20 or more mg prednisone equivalent for 1 month or more
– Alemtuzumab or temozolomide recipients
– Allogenic and select autologous (w/purine analogue conditioning Tx) HCT recipients
– Solid organ transplant recipients

There are a few SMX/TMP regimens… DS tab daily, DS tab qMWF, SS tab daily… there isn’t much direction to choose one. There was an RCT in HIV-infected patients that wasn’t statistically significant for daily SMX/TMP, but there was roughly 2x more discontinuation due to ADRs from the daily group.

I’ve personally seen DS tab qMWF most but it all depends on patient-specific factors such as adherence and recent lab work!

Goals and objectives: Oncology rotation

I’m anticipating a big jump from Clinical Orientation right into Oncology, and I hope that the previous very very basic knowledge I gained from the oncology elective in undergrad will be activated so I can build upon it and apply it in a meaningful way!

Goal #1: Develop a head to toe approach to assessing a patient for adverse drug events secondary to chemotherapy, or supportive agents for chemotherapy.
Objectives to meet this goal:
– Assess 3 patients per week, head to toe, for ADRs as practice.
– Develop a “hit list” for treating various ADRs from chemo, such as neuropathy, nausea and vomiting, and hand-foot syndrome
– Document in the chart my findings based on this assessment for at least 2 patients per week.

Goal #2: Be able to provide executable recommendations upon demand for proactive nausea and vomiting management based on the BCCA protocol the patient is on.
Objectives to meet this goal:
– Know 10 chemotherapy agents that automatically qualify a regimen to be “highly” emetogenic as per BCCA protocols and the Hesketh algorithm
– Be able to rationalize changes to nausea and vomiting prophylaxis and treatment based on patient response from previous cycle of chemotherapy
– Provide recommendations to the team for nausea and vomiting management for at least 2 patients per week

Goal #3: Develop a process for counselling oncology patients on either a new chemotherapy regimen or supportive care medications.
Objectives to meet this goal:
– Counsel at least 1 patient per week on supportive care medications that they will bring to a community pharmacy
– Counsel at least 2 patients per week on a new chemotherapy regimen as per BCCA protocols
– Ask for feedback on counselling skills in the oncology clinic setting from preceptor after each session.