Faculty Bibliography

BACKGROUND:Parameters within reconstitution, storage, stability, and administration may be optimized according to the unique pharmacokinetics of each antibiotic to ensure a successful desensitization. OBJECTIVE:The study aims to evaluate the successfulness and safety of antibiotic desensitization protocols developed by the pharmacy department at our institution. METHODS:A retrospective study was conducted at an 800-bed, urban, tertiary care, academic medical center. A total of 36 patients 18 years of age or older, admitted to our intensive care units between March 2013 and July 2017, who underwent antibiotic desensitization utilizing our pharmacy developed protocols were included. RESULTS:In 36 patients, 61 desensitization cases were identified and included; 17 (47%) were male, 27 (75%) were Caucasian, and the median age was 55 years (range 19-94). In all, 15 different antibiotics were administered for desensitization, with meropenem (n = 12, 20%), ampicillin (n = 7, 11%), piperacillin/tazobactam (n = 7, 11%), and penicillin (n = 7, 11%) being the most common; 59 (97%) of 61 desensitizations were completed successfully with or without experiencing reactions, and 53 (89%) of the successful desensitization cases were completed without reactions. Two cases were categorized as anaphylaxis, which was severe enough to terminate the desensitization process. Of the 59 cases successfully completed, the 6 (10%) cases that experienced reactions were managed successfully during desensitization with completion of the process. Conclusion and Relevance: The findings suggest that our pharmacy-developed antibiotic desensitization protocols are successful and safe and may be adapted by other institutions.

Inotropes are an integral component of the early stabilization of the patient presenting with cardiogenic shock. Despite years of clinical experience with the 2 most commonly used inotropes, dobutamine and milrinone, there remains limited data comparing outcomes between the two. We conducted a retrospective review to compare the effectiveness and safety of milrinone or dobutamine for the initial management of cardiogenic shock. Adult patients with cardiogenic shock regardless of etiology who received initial inotrope therapy with either milrinone (n = 50) or dobutamine (n = 50) and did not receive mechanical circulatory support were included. The primary end point was the time to resolution of cardiogenic shock. Changes in hemodynamic parameters from baseline and adverse events were also assessed. Resolution of shock was achieved in similar numbers in both the groups (milrinone 76% vs dobutamine 70%, P = .50). The median time to resolution of shock was 24 hours in both groups ( P = .75). There were no differences in hemodynamic changes during inotrope therapy, although dobutamine trended toward a greater increase in cardiac index. Arrhythmias were more common in patients treated with dobutamine than milrinone, respectively (62.9% vs 32.8%, P < .01), whereas hypotension occurred to a similar extent in both groups (milrinone 49.2% vs dobutamine 40.3%, P = .32). The use of concomitant vasoactive medications, dosage required, and duration of therapy did not differ between groups. There was no difference in the overall rate of discontinuation due to adverse event; however, milrinone was more commonly discontinued due to hypotension (13.1% vs 0%, P < .01) and dobutamine was more commonly discontinued due to arrhythmia (0% vs 11.3%, P < .01). Milrinone and dobutamine demonstrated similar effectiveness and safety profiles but with differences in adverse events. The choice of milrinone or dobutamine as initial inotrope therapy for cardiogenic shock may depend more on tolerability of adverse events.

Our goal was to provide comprehensive data on the effectiveness of ketamine in refractory status epilepticus (RSE) and to describe the potential consequences of long-term ketamine infusion. Ketamine, an N-methyl D-aspartate (NMDA) receptor antagonist, blocks excitatory pathways contributing to ongoing seizure. While ketamine use is standard in anaesthetic induction, no definitive protocol exists for its use in RSE, and little is known about its adverse effects in long-term, high-dose administration. We present two cases of RSE that responded rapidly to ketamine infusion, both with fatal outcomes secondary to metabolic acidosis and cardiovascular collapse. We performed a systematic review of the application and consequences of ketamine use in RSE. PubMed, Ovid, MEDLINE and PMC were searched for articles describing ketamine treatment for RSE according to a predetermined search strategy and inclusion criteria. The systematic review revealed wide discrepancies in ketamine dosing (infusion maintenance dose range 0.0075-10.5 mg/kg/hour), but good outcomes in medically managed RSE (75% of studies reported moderate or complete seizure control in adults, 62.5% in paediatrics). Additionally, literature review elucidated a potentially causal relationship between prolonged ketamine infusion and both cardiovascular and metabolic dysregulation. Ketamine is effective in RSE by antagonising excitotoxic NMDA receptors. However, there is high variability in ketamine dosing and scarce data on its safety in long-term infusion. Metabolic acidosis and haemodynamic instability associated with the use of long-term, high-dose ketamine infusions must be of concern to clinicians administering ketamine to critically ill patients.

Venous thromboembolism (VTE) is a major health concern associated with significant morbidity and mortality. Critically ill patients are at an increased risk of VTE compared to general medical patients due to unique risk factors: prolonged immobilization, invasive lines and devices, certain medications, and acquired thrombophilia. Furthermore, VTE in the critically ill is associated with increased duration of mechanical ventilation, increased length of intensive care unit and hospital stay, and a trend toward increased mortality. Clinical practice guidelines therefore recommend VTE prophylaxis with either subcutaneous heparin or low-molecular-weight heparin for all critically ill patients without contraindication. Yet, many patients will develop VTE despite appropriate pharmacologic prophylaxis, which has led to interest in risk-stratifying critically ill patients for more aggressive prophylaxis strategies. Recent research identified patients at highest risk of failure of thromboprophylaxis and provided insight into the pathophysiologic mechanisms. Obesity and the receipt of vasopressors are 2 risk factors consistently identified in observational studies; further clinical data support decreased absorption of anticoagulant administered via the subcutaneous route as the likely mechanism behind thromboprophylaxis failure in these patient populations. Several studies have investigated novel thromboprophylaxis strategies to circumvent pharmacokinetic limitations in patients who are obese or on vasopressors: increased fixed-dose, weight-based subcutaneous, or continuous intravenous infusion of a prophylactic dose of anticoagulant has shown promise in limited studies; however, the results have yet to demonstrate superiority compared to current standard-of-care. This review discusses observational studies identifying patients at risk of thromboprophylaxis failure and critiques clinical studies evaluating novel thromboprophylaxis strategies in high-risk, critically ill patients with a focus on their limitations. Future studies are currently being conducted that will provide further guidance into the appropriate use of individualized thromboprophylaxis.

Nephrotoxicity is a known adverse effect of polymyxin B (PMB). Animal data suggests that once daily dosing may reduce the rate and delay the onset of acute kidney injury (AKI).In a multicenter, retrospective study, we evaluated adult patients with a creatinine clearance (CrCl) ≥30 mL/min who received ≥48h of PMB therapy. The primary endpoint was the difference in rate of AKI comparing once and twice daily PMB dosing. Secondary endpoints included time to AKI and recovery of renal function.Of 273 eligible patients, 100 from each group were matched based on propensity scores. In the matched groups, nephrotoxicity, defined according to RIFLE criteria, was more frequent with once versus twice daily dosing (47% vs. 17% P=0.0005). After adjusting for residual differences by multivariate conditional logistic regression, once daily dosing was more likely to result in nephrotoxicity (adjusted odds ratio 2.5, 95% CI 1.413-4.541, P=0.002). Among 64 patients who developed AKI, the median onset was similar between groups (7 days with once vs. 6 days with twice daily dosing, P=0.095). Of 37 patients who had their serum creatinine evaluated subsequently, 29/37 (78%) had recovery of renal function. No patient required renal replacement therapy.Our findings suggest that AKI is significantly more common with PMB once daily as compared to twice daily dosing with no difference in time to AKI. Prospective randomized study is warranted to validate these results.

BACKGROUND:There is little data guiding clinicians on how to discontinue vasopressors among septic shock patients on concomitant norepinephrine (NE) and vasopressin (VP). OBJECTIVE:To determine the incidence of hypotension within 24 hours of discontinuing NE (NE DC first) versus VP (VP DC first) first in septic shock patients. METHODS:This retrospective study evaluated septic shock patients admitted to the medical intensive care unit (MICU) and surgical ICU (SICU) receiving concomitant NE and VP. Receipt of additional vasopressors, mixed shock states, expired or care withdrawn, and NE and VP discontinued simultaneously were exclusion criteria. The primary outcome was incidence of hypotension within 24 hours of first vasopressor discontinuation. Secondary outcomes included time to hypotension, hospital length of stay (LOS), ICU LOS, and ICU mortality. RESULTS:A total of 80 patients were included (NE DC first [n = 35]; VP DC first [n = 45]), with a median age of 73 years and median modified Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores of 21 and 7, respectively. More patients in the NE DC first group were in the SICU (42.9% vs 20.0%; P = 0.048) with more intra-abdominal infections (40.0% vs 15.6%; P = 0.021) and fewer appropriate empirical antibiotics (62.9% vs 86.7%; P = 0.018). Hypotension within 24 hours of first agent discontinuation was higher in the VP DC first group (28.6% vs 62.2%; P = 0.004), with similar hospital LOS and ICU mortality. Multivariate analysis identified VP DC first as an independent predictor of hypotension (odds ratio = 7.2; CI = 2.3-22.7). CONCLUSION/CONCLUSIONS:Among septic shock patients on concomitant NE and VP, discontinuation of VP first was associated with an increased incidence of hypotension; future prospective control trials are warranted.

Background: Novoseven is a recombinant preparation of human factor VIIa (rFVIIa) indicated for the treatment of bleeding episodes and perioperative management. Aims: To evaluate the cost and utilization of rFVIIa at a large academic medical center. Methods: We performed a retrospective review. Data collection included baseline characteristics, past medical history, and antithrombotic use. Utilization of rVIIa included indication for use, number of doses, and blood product administration within 24 hours. Incidence of venous thromboembolism (VTE), stroke, transient ischemic attack (TIA), death from systemic embolism, myocardial infarction (MI), hypersensitivity, and disseminated intravascular coagulation (DIC) were also collected. The primary outcome was utilization and cost of rVIIa at NYULH. Secondary outcomes included compliance to NYULH off-label dosing guideline, blood product administration, adverse effects, and thromboembolic events. Results: The majority of rFVIIa use was for refractory bleeding after cardiac surgery. Dosing was according to NYULH guideline, lower, and higher than recommended in 76.5%, 3.9% and 17.6% of cases respectively. The costs of rVIIa decreased after development of the off-label dosing guideline and transition from blood bank to pharmacy. The total incidence of thromboembolic events within 30 days was 19.6%; 17.6% arterial and 2% venous. Seventy percent of patients with an adverse event were over 70 years of age. Use of rFVIIa reduced the median number of units of blood products administered. Conclusions: Administration of rFVIIa for cardiac surgery appears to be effective for hemostasis. Transitioning rFVIIa from the blood bank to pharmacy and implementation of a dosing guideline appears to have reduced costs. Patients receiving rFVIIa should be monitored for thromboembolic events. Elderly patients may be at higher risk for thromboembolic events and further literature is needed to determine the optimal use of rFVIIa or if other hemostatic agents may be warranted in this population

Extended infusion (EI) administration of β-lactams can improve target attainment in critically ill patients with altered pharmacokinetics/pharmacodynamics. To optimize meropenem dosing in patients with severe sepsis/septic shock, our Antimicrobial Stewardship Program implemented a EI meropenem (EIM) protocol in an 18-bed Medical Intensive Care Unit in March 2014. In this retrospective study, we compared intensive care unit (ICU) mortality and clinical response in patients who received meropenem for ≥72 hours administered per EIM protocol of 1 g over 3 hours every 8 hours versus intermittent infusion (IIM) protocol of 500 mg over 30 minutes every 6 hours. Age, weight, comorbidities, severity of illness, and vasopressor use were comparable between groups (EIM protocol n = 52, IIM protocol n = 96). The IIM protocol group had higher rates of renal dose adjustment at meropenem initiation. Among 56 identified gram-negative (GN) pathogens, 94% had meropenem minimal inhibitory concentration ≤0.25 mg/L. The ICU mortality was lower (19 vs 37%; P = .032) and clinical response was higher (83% vs 46%; P < .01) in the EIM protocol versus IIM protocol group. Total vasopressor days were shorter (2 vs 3 days; P = .038), and white blood cell normalization rate was higher (87% vs 51%; P < .01) in the EIM protocol versus IIM protocol group. There was no difference in days of mechanical ventilation, duration of therapy, and ICU stay. The IIM protocol was also identified as an independent risk factor associated with ICU mortality (hazard ratio: 3.653, 95% confidence interval: 1.689-7.981; P = .001) after adjusting for Sequential Organ Failure Assessment score. In this cohort of patients with severe sepsis/septic shock and highly susceptible GN pathogens, there was improved mortality and clinical response in the EIM protocol group.

Cancer is a known hypercoagulable state that leads to an increased risk of venous thromboembolism (VTE). Low molecular weight heparin remains the preferred anticoagulant for VTE in patients with cancer over vitamin K antagonist. However, the preferred anticoagulant in prevention of stroke and systemic embolism in atrial fibrillation (AF) in patients with cancer has yet to be determined. The direct oral anticoagulants (DOACs) are increasingly being utilized; however their role in cancer has only recently been investigated. The objective of this retrospective cohort was to describe real-world anticoagulation prescribing patterns in cancer patients at a large academic medical center between January 1, 2013 and October 31, 2016. We sought to assess the safety, tolerability, and efficacy of DOACs in patients with cancer for either VTE and/or AF. Patient demographic, clinical characteristics, as well as bleeding and thrombotic events were collected. There were 214 patients in our analysis, of which 71 patients (33%) received a DOAC [apixaban (n = 22), dabigatran (n = 17), and rivaroxaban (n = 32)]. There were fewer bleeding events and/or discontinuations in the DOAC group compared to enoxaparin (13 vs. 27, p = 0.022). There was no difference in major or minor bleeds or thromboembolic events in comparing DOAC to enoxaparin or DOAC to warfarin. This was a retrospective, single-institution study assessing the safety and efficacy of DOACs compared to warfarin or enoxaparin in patients with cancer. DOACs may represent an alternative to warfarin or enoxaparin in patients with cancer for VTE and/or stroke reduction in AF.