Author: mahadam

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 at BCCA 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!

Reflections on Clinical Orientation

First clinical rotation complete!! The CTU was awesome, the medical team was receptive, and the St. Paul’s pharmacists were welcoming of us residents. Although the intent of the rotation was to keep it focused on developing a process and not so much delving into therapeutics, I found myself learning a lot through working up various patients. Already by the end of the rotation, I felt like I was just hitting my stride in information gathering, and have begun to crystallize a process in formulating plans. What I still need to work on overall is creating concrete and executable plans for all the medical problems that my patient has, although prioritizing them has not been a challenge as of yet. So, how did I do on my goals?

Goal #1: Holistically incorporate radiographic findings and be able to apply them to rationalize diagnoses to better develop a pharmacotherapeutic plan – I believe I have met this goal. I did look up any terms I did not understand, and used reasoning from a diagnostic test (a CXR) to rationalize that what I was seeing (in one of my patients who had CHFpEF and a query pneumonia) was more likely a pneumonia and as such should be treated based on those findings and her symptoms. This helped me better understand the medical team’s plan.

Goal #2: Become proficient at performing medication reconciliation, and proactively take action to resolve any discrepancies – During this rotation I did not get to take part in an observed medication history. However, given the characteristics of some of my patients, whether there is a language barrier, or medical literacy was low (so they did not know what they took/why they take medications/how often each medication is taken), or uncooperative patients, I became better at taking focused medication histories for the information that I most urgently needed. One example was planning a discharge for a patient who took various traditional Chinese herbal products. This patient was also on warfarin, so I had to take a quick history of her NHPs and determine if any of them interacted with it. In my future rotations, I look forward to being involved with reconciling medication histories alongside the physicians.

Goal #3: Be able to work up a relatively simple patient (<6 medical conditions) in under 3 hours – I don’t think there was a patient that I had who had <6 medical conditions during Clinical Orientation! Such is the life in CTU. However, I found that with each subsequent workup, I became more efficient in gathering pertinent data. I look forward to working on my efficiency further and being more efficient in getting up to speed on medical conditions that I may not have seen before. I did keep therapeutics notes in a notebook and wrote down things I may need to unpack later.

All in all, it was an enriching rotation and I look forward to continuing to build and refine my process.

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.

Nuggets of Knowledge – July 31st hodge podge: warfarin bridging, lumbar puncture findings, and ID tidbits

When to NOT bridge warfarin with LMWH following a procedure (low risk)
– Laprascopic surgery
– Dermatologic procedures
– Ophthalmologic procedures
– Colonoscopies
– Bone marrow aspirate and biopsy, lumbar punctures
– Thoracentesis

CSF findings that would raise suspicion of viral encephalitis (not meningitis)
– Increased WBC but <250/mL
– Increased protein but <150 mg/dL
– Normal glucose (decreased with herpes simplex)
– RBC usually absent, but positive in HSV-1 or if contaminants present

Gram-negative bacilli may be divided into fermenters and non-fermenters.
Fermenters can be found in GI/GU: 
E. coli, Proteus mirabilis, Klebsiella spp.
Non-fermenters (skin, resp, GU): Pseudomonas aeruginosa, Acinetobacter spp., Legionella pneumophila

Acinetobacter susceptibilities follow Pseudomonas susceptibilities closely!

And while I’m at it..
Gram-negative cocci
– Neisseria gonorrhoeae
– Neisseria meningitidis
– Moraxella catarrhalis
– Haemophilus influenzae

ADS – Acid-base disorders

During EBM week, we learned that one of the most common reasons why learners motivate themselves to learn something that they don’t otherwise want to learn is a fear of failure or humiliation. Not that I didn’t want to learn this, as acid-base disorders was an area that weren’t touched upon in the undergrad curriculum (except for one lecture in the renal elective), but Dr. Brown’s lecturing style certainly motivates one to do the pre-readings and do them well.

I won’t go over WHAT was taught as I feel that I have a good grasp on what was covered and I just need to practice it – any patient who has labs drawn, or arterial blood gases done, I will try to evaluate them and see if there is an acid-base disorder. I have a good idea of what causes each of the disorders, and how that will influence drug therapy – example is a metabolic acidosis where replenishment of bicarb is necessary… but bicarbonate is reconstituted in a bag of NS…which has 154 mEq/L. Not nice!

Normal pCO2 = 40 mm Hg
Normal HCO3 = 24 mm Hg (21-28)
Normal anion gap = 10 (8-12)… ADJUST NORMAL down by 2 for every 10 g/L drop in serum albumin (N = 42-46 g/L)

One pearl I must record though is that potassium usually follows blood pH changes due to shunting of potassium (a cation) into or out of the cell to maintain ion balance.
– As pH DECREASES in acidemia, potassium INCREASES
– As pH INCREASES in alkalemia, potassium DECREASES

I’m more a systems kind of person and I like a systematic way of evaluating anything. For that reason, I found acid-base disorders to be easy to wrap my head around. As long as I have the labs, the blood pH is the main anchor and will let me determine whether it is an acidemia or alkalemia. The corroborating signs, symptoms, and labwork will allow me to confirm that the drug therapy for the appropriate diagnosis is the best for the patient.

ADS – Clinical pharmacokinetics approach to aminoglycoside and vancomycin dosing

I found myself repeating the old adage from 2nd year pharmacokinetics that Dr. Ensom said: “if you want the chicken to be finger lickin’ good, you have to use the Colonel’s recipe!” For the majority of patients, the “recipe”, i.e. dosing protocol will work just fine, but this session was mostly me trying to remember how the heck I even knew how to use those equations in The Kentucky Manual…anyway, here are some pertinent points I got from the morning’s session.

Aminoglycosides (Vd = 0.2-0.3 L/kg and t1/2 = 2 hours for adults);  – use the VCH dosing protocol for traditional or extended interval dosing. Do NOT use extended interval in: pregnancy, burns >20% BSA, pts on dialysis, or septic shock. Basically anyone who would have increased clearance such that the post-antibiotic effect will not extend to 24 hours.
To load or not to load? – YES, unless you are doing once-daily extended interval dosing.
When do you take a level? – before the 3rd dose within 30 mins, and 30 mins after the half-hour infusion (4th dose). No levels for extended interval dosing as the trough will be undetectable anyway.
How do you monitor for toxicities? – vestibular toxicity manifests in 1-2 weeks, so get audiology involved if you suspect it. Nephrotoxicity happens quicker.
Adjusting doses based on levels – if your patient’s renal function is stable, and their clinical course is stable, and they have received all their doses and are at steady state… you can use the “cheat” method for a peak level. For everything else, there’s Masterca- The Kentucky Manual. Also useful if the levels were not drawn correctly at the right time.

The “cheat” equation: New dose = old dose * (desired level/actual level) 

Vancomycin (Vd = 0.6-0.8 L/kg and t1/2 = 4-6 hours for adults) – use the VCH/PHC dosing protocol.
To load or not to load? – YES…although in the course of doing the literature search for my project, I found that the evidence of a loading dose is not very extensive, but if a patient’s bacteremic, or they have meningitis, you wouldn’t deny them a load, right?
When do you take a level? – I thought this was cut and dry, before the 4th dose then use the cheat equation above to adjust the dose. HOWEVER, Dr. Loh presented an interesting case where one would have to improvise. A level may not even be warranted for an otherwise healthy patient who may not get vanco past 7 days. Post-levels are usually not indicated, and only reserved for unique cases such as in the case of renal failure or burns, or unstable clinical status warranting calculation of individual PK parameters.
In the setting of fulminant renal failure, it might be advisable to give a “mini-load” for the patient if a suboptimal dose was given in Emerg. After that, a random vanco level may be the best option just to see how the patient is clearing the drug.
If a load was given in Emerg, technically you could take a level pre-3rd dose assuming that the patient’s clinical status has remained stable. – the half-life of vanco is 4-6 hours, so steady state should be reached in 20-30 hours… assuming q12h dosing, that would fall within before the 3rd dose.
How do you monitor for toxicities? – there are some that are dose-related, i.e. red man syndrome and ototoxicity, and some that are not, such as nephrotoxicity (but really…vanco is not that nephrotoxic, one would be more worried about the other medications on board that may be nephrotoxic). NEUTROPENIA actually occurs in 1-10% of patients (as per Lexicomp) but it only manifests after 1-2 weeks of treatment.

Overall, I feel more confident than when I walked in that morning in terms of my ability to evaluate a patient’s AMG or vancomycin regimen. I also learned that sometimes you may have to improvise and think clinically to solve dosing issues – but that’s why we are on the ward! If everything were perfectly protocolized, physicians wouldn’t need us!

Nuggets of Knowledge: Causes of elevated lactate, and some pearls on myelodysplastic syndromes

Some causes of an elevated lactate include:
– Decreased renal function
– Comorbid liver disease
– Decreased tissue perfusion, hemodynamic instability (like sepsis)
– Active alcohol abuse
– Decompensated HF
– Hypoxic state

Myelodysplastic syndromes – risk and prognosis measured by DIPSS score, taking into account (one point each): age >65 yo, leukocytes >25, Plts <100, required transfusion, circulating blasts 1% or above, unfavourable karyotype, fever/sweats/wt loss preceding Dx. High risk DIPSS is for a score of 3 or above.
– DIPSS factors into decision making for drug therapy. High risk = allogenic HCT is favoured. Low risk = symptomatic care such as DNA hypomethylating agents, transfusion, G-CSF, or darbepoeitin may be favoured.
– Iron chelation therapy post-transfusion initiated if ferritin is constantly elevated >1000, AND pt is stable (no comorbid infections), DIPSS low risk (0-1) may favour iron chelation.