Ten year experience with student pharmacist research within a health system and education center

INTRODUCTION

Skills gained from research experience allow student pharmacists to evolve as practitioners, innovators and perpetual learners in an increasingly complex healthcare environment. Data published regarding pharmacy resident research are focused on external dissemination rates and research programs. Little is published regarding student research.

METHODS

This descriptive study was a five-year before and after comparison between the existing co-curricular model and a new longitudinal, 12-month research advanced pharmacy practice experience (L-APPE) model for student pharmacist research. The objective was to describe the development and transition to the L-APPE and compare the models in external dissemination rates and preceptor-classified impact on patient care. Preceptors were surveyed to characterize the impact on the health care institution.

RESULTS

Over a ten-year period, 65 fourth year students engaged in research. From 2006-2011, 28 students (43.4% of student cohort) completed co-curricular research projects. From 2011-2016, 37 students (40.2% of student cohort) completed the L-APPE. The number of national poster presentations increased 6-fold with the L-APPE, from 6 (21.4%) to 36 (97.3%) (p < 0.01). Combined posters and peer reviewed publications had a 350% higher occurrence (RR 4.5, 95% CI 1.9-10.9; p < 0.01). Preceptors classified L-APPE projects 1.5 times more often as leading to a change or affirmation of a practice model or prescribing pattern (83.3% vs 57.1%; p = 0.03).

DISCUSSION AND CONCLUSIONS

The L-APPE research model increased external dissemination rates and resulted in more meaningful practice model or prescribing pattern benefits. Additional study of pharmacy student research is warranted.

Pharmacist-Provided Medication Management in Interdisciplinary Transitions in a Community Hospital (PMIT)

BACKGROUND

Medication management during transitions of care (TOC) impacts clinical outcomes. Published literature on TOC implementation is increasing, but data remains limited regarding the optimal role for the inpatient pharmacist, particularly in the community health setting.

OBJECTIVE

To evaluate the impact of a dedicated inpatient TOC pharmacist on re-presentations following discharge.

METHODS

This is a prospective study with historical control. All adult patients discharging home from study units were eligible. The TOC pharmacist (1) reviewed medication history and admission reconciliation, (2) met the patient/caregiver to assess barriers, (3) reviewed discharge reconciliation, (4) performed discharge education, and (5) communicated with next level of care. The primary outcome was 30 day re-presentation rate. Secondary outcomes included 60, 90, and 365 day re-presentation rates. IRB approval was obtained.

RESULTS

Three hundred and eighty four patients met inclusion criteria. When compared to 1,221 control patients, the intervention had an 11% absolute and 50.2% relative reduction in 30 day re-presentation rate (OR 0.43, 95% CI 0.30-0.61, NNT 9). Reductions in re-presentations at 60, 90 and 365 days remained statistically significant. Utilization avoidance was $786,347. For every $1 invested in pharmacist time, $12 was saved. The TOC pharmacist made a total of 904 interventions (mean 2.4 per patient).

CONCLUSION

This study provides new information from previous studies and represents the largest study with significant and sustained reductions in re-presentations. Integrating a pharmacist into an interdisciplinary team for medication management during TOC in a community health system is beneficial for patients and financially favorable for the institution.

Midodrine for the weaning of vasopressor infusions

WHAT IS KNOWN AND OBJECTIVE

Midodrine, an orally available α1-agonist indicated for the treatment of orthostatic hypotension, has been used at our institution as an adjunctive treatment to provide haemodynamic support to facilitate intravenous (IV) vasopressor weaning. Limited published data exist for this off-label use; thus, the objective of this study was to evaluate outcomes in patients who received midodrine for IV vasopressor weaning compared to control patients.

METHODS

This retrospective comparison included adult ICU patients admitted to our institution from January 2007 to March 2012. The primary outcome was the time to IV vasopressor discontinuation after midodrine initiation. Secondary outcomes included a comparison between midodrine and control patients of the time from IV vasopressor discontinuation to ICU discharge, hospital and ICU length of stay (LOS), and the number of ICU readmissions.

RESULTS AND DISCUSSION

The analysis included 188 patients (94 midodrine and 94 control). Patients discontinued IV vasopressors a median of 1·2 days (IQR 0·5-2·8) after midodrine initiation. ICU discharge occurred sooner after IV vasopressor discontinuation (0·8 vs. 1·5 days, P = 0·01), and 96% of patients remained off IV vasopressors after midodrine treatment. Hospital LOS was longer in midodrine patients (P < 0·01), but there were no differences in ICU LOS or readmissions. Adverse event rates after midodrine use were consistent with those observed in other studies.

WHAT IS NEW AND CONCLUSION

Midodrine may serve as a useful adjunct to wean IV vasopressors in difficult-to-wean patients. Further studies are needed to assess the efficacy and safety of midodrine for this indication.

Outcomes Associated With Prothrombin Complex Concentrate for International Normalized Ratio Reversal in Patients on Oral Anticoagulants With Acute Bleeding

BACKGROUND

Management of bleeding in patients on oral anticoagulants (OACs) is crucial in optimizing outcomes. No large studies examine 3-factor prothrombin complex concentrate (PCC) for OAC reversal.

OBJECTIVE

To assess outcomes after administration of 3-factor PCC for reversal of international normalized ratio (INR).

METHOD

We conducted an institutional review board-approved retrospective cohort study in all patients admitted to our level II trauma center over a 5-year period from 2007 to 2012 who received PCC for INR reversal and bleeding management. The primary outcome was assessment of efficacy as measured by achievement of INR < 1.5. Secondary objectives were to evaluate: factors associated with achievement of target INR, cessation of bleeding, mortality, outcome differences with or without fresh frozen plasma (FFP) or protocol utilization, safety, and cost.

RESULT

A total of 403 patients were evaluated. Target INR was achieved in 88.8% of patients and was influenced by baseline INR. Associated factors were younger age (P = 0.02), utilization of the institution's protocol (P < 0.01), and concomitant administration of vitamin K (P < 0.01). Concomitant FFP did not affect achievement. Bleeding cessation occurred in 333 (82.6%) patients, and 68 (16.9%) patients died. Patients who achieved target INR were more likely to have bleeding cessation (P < 0.01). The odds of survival for those who reached target INR was 3.8 times greater (P < 0.01). The incidence of thromboembolism was 3.7%.

CONCLUSION

Three-factor PCC administration with IV vitamin K was effective for INR reversal and bleeding cessation and should continue to be a mainstay of therapy pending head-to-head outcome and cost comparisons with 4-factor products.

The association of health literacy with time in therapeutic range for patients on warfarin therapy

Patients on warfarin therapy need to achieve and maintain anticoagulation control in order to experience the benefits of treatment while minimizing bleeding risk. Low health literacy skills may hinder patients' ability to use and adhere to warfarin in a safe and effective manner. The authors conducted this study to evaluate the relationship between health literacy and anticoagulation control among patients on chronic warfarin therapy. Participants were recruited from 2 diverse anticoagulation clinics in North Carolina. Time in therapeutic range (TTR) for warfarin therapy was used as a measure of anticoagulation control. Health literacy was assessed using the short form of the Test of Functional Health Literacy in Adults (S-TOFHLA). Of the 198 study participants, 51% had limited health literacy (S-TOFHLA score of 0-90) and 33% had poor anticoagulation control (TTR<50%). Participants with limited health literacy were less likely to correctly answer warfarin-related knowledge questions. Limited health literacy was significantly associated with TTR<50% (adjusted odds ratio=2.34, 95% CI [1.01, 5.46]). Findings indicate that limited health literacy is associated with poor anticoagulation control for patients on warfarin therapy. Lack of medication understanding may hinder the safe and effective use of this narrow therapeutic index drug.

Subdural hematoma after a fall in an elderly patient taking high-dose omega-3 fatty acids with warfarin and aspirin: case report and review of the literature

The elderly population is at an increased risk for major bleeding, possibly due to increased sensitivity to anticoagulation, multiple comorbidities, and polypharmacy. Elderly patients receiving antiplatelet and anticoagulant therapy have an additional risk for bleeding. Omega-3 fatty acids, also known as fish oil, have been used for hyperlipidemia, coronary heart disease, hypertension, and other conditions. Some studies have demonstrated that consumption of fish oil concentrate, n-3 polyunsaturated fatty acid (n-3 PUFA), results in cardiovascular benefits that include reductions in mortality, sudden death, nonfatal myocardial infarction, and thrombotic stoke, as well as improvement in graft patency. The mechanism of action of n-3 PUFA is not completely understood, but a dual antiplatelet and anticoagulant effect has been proposed. Few data exist on whether or not fish oil can be used safely with other antiplatelet or anticoagulant drugs. We report the case of a patient who after a minor fall developed a subdural hematoma requiring craniotomy that likely was precipitated by concomitant use of high-dose omega-3 fatty acids 6 g/day with both aspirin and warfarin. These findings are important because of the wide availability of omega-3 fatty acids and the propensity for use of complementary and alternative medicine in patients with cardiovascular disease who are already taking antiplatelet and/or anticoagulant agents. Judicious use of these combinations is advised, and pharmacists can play an important role in educating patients and other health care providers about the bleeding risks associated with combination therapy.

Drug interactions with cisapride: clinical implications

Cisapride, a prokinetic agent, has been used for the treatment of a number of gastrointestinal disorders, particularly gastro-oesophageal reflux disease in adults and children. Since 1993, 341 cases of ventricular arrhythmias, including 80 deaths, have been reported to the US Food and Drug Administration. Marketing of the drug has now been discontinued in the US; however, it is still available under a limited-access protocol. Knowledge of the risk factors for cisapride-associated arrhythmias will be essential for its continued use in those patients who meet the eligibility criteria. This review summarises the published literature on the pharmacokinetic and pharmacodynamic interactions of cisapride with concomitantly administered drugs, providing clinicians with practical recommendations for avoiding these potentially fatal events. Pharmacokinetic interactions with cisapride involve inhibition of cytochrome P450 (CYP) 3A4, the primary mode of elimination of cisapride, thereby increasing plasma concentrations of the drug. The macrolide antibacterials clarithromycin, erythromycin and troleandomycin are inhibitors of CYP3A4 and should not be used in conjunction with cisapride. Azithromycin is an alternative. Similarly, azole antifungal agents such as fluconazole, itraconazole and ketoconazole are CYP3A4 inhibitors and their concomitant use with cisapride should be avoided. Of the antidepressants nefazodone and fluvoxamine should be avoided with cisapride. Data with fluoxetine is controversial, we favour the avoidance of its use. Citalopram, paroxetine and sertraline are alternatives. The HIV protease inhibitors amprenavir, indinavir, nelfinavir, ritonavir and saquinavir inhibit CYP3A4. Clinical experience with cisapride is lacking but avoidance with all protease inhibitors is recommended, although saquinavir is thought to have clinically insignificant effects on CYP3A4. Delavirdine is also a CYP3A4 inhibitor and should be avoided with cisapride. We also recommend avoiding coadministration of cisapride with amiodarone, cimetidine (alternatives are famotidine, nizatidine, ranitidine or one of the proton pump inhibitors), diltiazem and verapamil (the dihydropyridine calcium antagonists are alternatives), grapefruit juice, isoniazid, metronidazole, quinine, quinupristin/dalfopristin and zileuton (montelukast is an alternative). Pharmacodynamic interactions with cisapride involve drugs that have the potential to have additive effects on the QT interval. We do not recommend use of cisapride with class Ia and III antiarrhythmic drugs or with adenosine, bepridil, cyclobenzaprine, droperidol, haloperidol, nifedipine (immediate release), phenothiazine antipsychotics, tricyclic and tetracyclic antidepressants or vasopressin. Vigilance is advised if anthracyclines, cotrimoxazole (trimethoprim-sulfamethoxazole), enflurane, halothane, isoflurane, pentamidine or probucol are used with cisapride. In addition, uncorrected electrolyte disturbances induced by diuretics may increase the risk of torsade de pointes. Patients receiving cisapride should be promptly treated for electrolyte disturbances.

Torsade de pointes resulting from the addition of droperidol to an existing cytochrome P450 drug interaction

OBJECTIVE

To report a case of QT prolongation associated with concomitant cyclobenzaprine and fluoxetine administration followed by torsade de pointes potentiated by droperidol.

CASE SUMMARY

A 59-year-old white woman who had been receiving long-term fluoxetine and cyclobenzaprine therapy was admitted for Achilles tendon repair. Baseline QTc was prolonged at 497 msec. Prior to surgery, the patient received droperidol, an agent known to prolong the QT interval. During surgery the patient developed torsade de pointes, which progressed into ventricular fibrillation. On postoperative day 1, after cyclobenzaprine discontinuation, the QTc decreased toward normal (440 msec).

DISCUSSION

Cyclobenzaprine shares anticholinergic effects, tachycardia, and dysrhythmic potential with the tricyclic antidepressants (TCAs). Fluoxetine is a known inhibitor of the CYP2D6 isoenzyme (along with CYP3A4 and CYP2C) and has been shown to increase TCA serum concentrations. The combination of cyclobenzaprine and fluoxetine resulted in significant QT prolongation in our patient that progressed to torsade de pointes after preoperative droperidol administration. Resolution of QT abnormalities after cyclobenzaprine discontinuation provided further evidence of a drug-induced etiology. Other possible medical and drug-related causes of torsade de pointes are reviewed and ruled out.

CONCLUSIONS

Clinicians should be aware of the dysrhythmic potential of cyclobenzaprine and fluoxetine, monitor for other cytochrome P450 inhibitors, and avoid concomitant drugs known to prolong the QT interval.

Update: clinically significant cytochrome P-450 drug interactions

Recent technologies have resulted in an explosion of information concerning the cytochrome P-450 isoenzymes and increased awareness of life-threatening interactions with such commonly prescribed drugs as cisapride and some antihistamines. Knowledge of the substrates, inhibitors, and inducers of these enzymes assists in predicting clinically significant drug interactions. In addition to inhibition and induction, microsomal drug metabolism is affected by genetic polymorphisms, age, nutrition, hepatic disease, and endogenous chemicals. Of the more than 30 human isoenzymes identified to date, the major ones responsible for drug metabolism include CYP3A4, CYP2D6, CYP1A2, and the CYP2C subfamily.

Diltiazem-associated thrombocytopenia

Nine days after starting diltiazem therapy for new-onset atrial fibrillation, a patient's platelet count had diminished to 61 x 10(3)/mm3, and 2 weeks later the nadir was reached at 23 x 10(3)/mm3. No hypersensitivity reaction otherwise was noted, and other hematologic values were unaffected. The patient's platelet counts were not affected by platelet transfusions. Bone marrow examination showed normal to increased numbers of megakaryocytes, suggesting peripheral destruction. After discontinuing diltiazem and administering high-dose immunoglobulin infusions, the platelet count returned to normal. This case suggests an immune-mediated cause for thrombocytopenia after exposure to diltiazem.

Pharmacokinetics of vancomycin in adult cystic fibrosis patients

Although the depositions of many antibiotics are altered in cystic fibrosis patients, that of vancomycin has not been studied. To assess vancomycin pharmacokinetics, 10 adult cystic fibrosis patients were given a parenteral dose of vancomycin (15 mg/kg) during the first 72 h of hospitalization for acute bronchopulmonary exacerbation. Blood samples were obtained at 0, 1, 1.25, 1.5, 2, 3, 4, 6, 8, 12, 15, and 24 h. The mean (standard deviation) weight, measured creatinine clearance, and Taussig clinical score were 51 (13) kg, 130 (39) ml/min/1.73 m2, and 64 (13), respectively. Multicompartmental pharmacokinetic parameters were best described by a two-compartment model. The mean (standard deviation) volume of distribution, total body clearance, and terminal elimination rate constant were 0.58 (0.15) liter/kg, 91 (19) ml/min/1.73 m2, and 0.123 (0.05) h-1, respectively. These values were consistent with vancomycin pharmacokinetic parameters obtained in previous studies of healthy adult volunteers. Vancomycin dosages predicted by using a two-compartment Bayesian model were approximately 15 mg/kg every 8 to 12 h. There were poor correlations between clinical score or creatinine clearance and any pharmacokinetic parameter (r values of < 0.32). The coefficient of correlation between urine flow rate and total body clearance was 0.7 (P < 0.05). Adult cystic fibrosis patients exhibit a disposition of vancomycin similar to that exhibited by healthy adults, and thus cystic fibrosis does not alter vancomycin pharmacokinetics.