Outpatient Parenteral Antimicrobial Therapy at Large Veterans Administration Medical Center | Page 4
Published Online: September 13, 2013
Andrew Lai, MD; Thuong Tran, PharmD; Hien M. Nguyen, MD; Jacob Fleischmann, MD; David O. Beenhouwer, MD; and Christopher J. Graber, MD, MPH
Any analysis of an OPAT program must include the 2 most common complications of extended intravenous antimicrobial therapy: line-related complications and adverse drug events. In a cohort of 2059 OPAT episodes over a 13-year period, Matthews and colleagues9 reported (for self-administered and healthcare professional–administered OPAT, respectively) overall complication rates of 24% and 23%, readmission rates of 10.5% and 12.6%, vascular device complication rates of 1% and 0.5%, and drug adverse-event rates of 12%. Our 4-year experience was similar to these findings, other than a higher frequency of line complications. However, our rates of line-related complications did decrease annually from 2006 to 2009. We believe that this decrease was partially due to several OPAT protocol changes implemented in 2007: (1) a telephone follow-up was performed on the day following discharge to ensure proper implementation of OPAT by pharmacy and nursing agencies; (2) weekly phone calls were made to the patient with the express purpose of troubleshooting and to ensure compliance with lab monitoring; and (3) increased allowances were made for nursing visits for PICC dressing changes. Of note, only 1 episode of line-related venous thrombosis (brachial vein thrombus) was diagnosed in our study. The reported incidence of catheterrelated thrombotic complications has varied, depending on the patient population studied, catheter location, and diagnostic modalities utilized. In a retrospective analysis of 2063 patients who received a PICC for intravenous antibiotics, the incidence of venous thrombosis was 2.5% with a mean time to diagnosis of 18.7 days. Deep venous thromboses slightly outnumbered superficial thromboses (55.8% vs 44.2%), and pulmonary embolism was diagnosed in 2 patients.10 We have no explanation for our unusually low rates of venous thrombosis complications. The potentially subclinical nature of venous thrombosis is, of course, recognized. Nevertheless, a low rate of venous thromboses portends favorably for avoiding the potentially life-threatening complication of pulmonary embolism.
Our overall rate of adverse drug events was 10.2%, which is similar to what has been previously reported in the literature.9 Although more patients had adverse events with vancomycin than with other commonly used agents in our study, vancomycin’s overall ratio of adverse events to courses received was similar to that of the other agents. In a multicenter series from 1997 through 1999 following 1053 episodes of outpatient vancomycin administration, adverse events were reported in 11.3% of patients, with rash being the most common (3% of all episodes). A “renal toxic reaction” was encountered in 1.5% of all courses.11 While the total number of adverse drug events due to vancomycin approximates that reported in previous studies, our proportion of vancomycin-associated acute kidney injury was higher (5.5%). We postulate that our higher rate of vancomycin-related acute kidney injury may be related to our protocol of aiming for high goal vancomycin troughs (15-20 mg/L) for the treatment of invasive S aureus infection, an approach advocated by recent guidelines issued by the Infectious Diseases Society of America, the American Society of Health-System Pharmacists, and the Society of Infectious Diseases Pharmacists.12 The relationship between elevated vancomycin troughs and nephrotoxicity admittedly remains a subject of debate, as many studies are limited by concomitant nephrotoxic agents, varying definitions of nephrotoxicity, and an inability to determine whether an elevated trough leads to nephrotoxicity or vice versa.12,13
It is unclear why ESRD was associated with OPAT noncompletion in our study, but this association likely speaks to the complexity of illness of this particular patient population and potential issues related to hemodialysis access that should prompt further study. Also, a majority of our ESRD population receives hemodialysis outside of our system, so coordination of care may have been an issue as well.
Our OPAT experience may differ from others for a variety of reasons. Most notably, the advanced age and high background rate of comorbidites of the average VA patient may not reflect the general population encountered by other OPAT programs. In fact, it is conceivable that patients with similar profiles might routinely be transferred to a skilled nursing facility to complete their antibiotic therapy. Cox and colleagues14 previously demonstrated in a series of 205 patients that OPAT could be self-administered to older adults with a rate of efficacy and safety similar to that of the comparator arm of younger patients. Our data support this option as a means to complete intravenous antibiotic therapy without institutionalization in a short-term healthcare facility. In addition, our data demonstrate the ability to deliver OPAT over a wide catchment area, as nearly 65% of our patients who received OPAT lived more than 20 miles from our facility. Our patients also benefit from an integrated healthcare system with longitudinal follow-up from initial point of care; this design increases adherence and may reduce rates of OPAT-related complications. Furthermore, our OPAT program enjoys the benefit of a full-time infectious diseases pharmacist who has primary responsibility for coordinating services between home health nursing, laboratory services, pharmacy, and multiple physicians (inpatient, prescribing, and outpatient primary care). The value of a centralized coordinator who can tie together the issues of infectious diseases and pharmacology cannot be overstated.
Author Affiliations: From Department of Medicine, Huntington Hospital (AL), Pasadena, CA; Infectious Diseases Section (TT, JF, DOB, CJG), VA Greater Los Angeles Healthcare System, Los Angeles, CA; Pharmacy Service (TT), VA Greater Los Angeles Healthcare System, Los Angeles, CA; Kaiser Permanente Northwest (HMN), Portland, OR; David Geffen School of Medicine at the University of California (JF, DOB, CJG), Los Angeles, CA.
Funding Source: None.
Author Disclosures: The authors (AL, TT, HMN, JF, DOB, CJG) report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.
Authorship Information: Concept and design (TT, JF, DOB, CJG); acquisition of data (TT, HMN, JF, DOB, CJG); analysis and interpretation of data (AL, TT, JF, CJG); drafting of the manuscript (AL, TT, DOB, CJG); critical revision of the manuscript for important intellectual content (AL, TT, JF, DOB, CJG); statistical analysis (TT, CJG); provision of study materials or patients (CJG); administrative, technical, or logistic support (TT, JF); and supervision (TT, JF, DOB, CJG).
Address correspondence to: Christopher J. Graber, MD, MPH, Infectious Diseases Section, VA Greater Los Angeles Healthcare System, 11301 Wilshire Blvd, 111-F, Los Angeles, CA 90073. E-mail: firstname.lastname@example.org.
1. Rucker RW, Harrison GM. Outpatient intravenous medicatios in the management of cystic fibrosis. Pediatrics. 1974;54(3):358-360.
2. Delgado-Rodríguez M, Bueno-Cavanillas A, López-Gigosos R, et al. Hospital stay length as an effect modifier of other risk factors for nosocomial infection. Eur J Epidemiol. 1990;6(1):34-39.
3. Hauck K, Zhao X. How dangerous is a day in hospital? a model of adverse events and length of stay for medical inpatients. Med Care. 2011;49(12):1068-1075.
4. Sáez-Castillo AJ, Olmo-Jiménez MJ, Pérez Sánchez JM, Negrín Hernández MA, Arcos-Navarro A, Díaz-Oller J. Bayesian analysis ofnosocomial infection risk and length of stay in a department of general and digestive surgery. Value Health. 2010;13(4):431-439.
5. Lim SC, Doshi V, Castasus B, Lim JK, Mamun K. Factors causing delay in discharge of elderly patients in an acute care hospital. Ann Acad Med Singapore. 2006;35(1):27-32.
6. Hoogerduijn JG, Schuurmans MJ, Duijnstee MS, de Rooij SE, Grypdonck MF. A systematic review of predictors and screening instruments to identify older hospitalized patients at risk for functional decline. J Clin Nurs. 2007;16(1):46-57.
7. Bernard L, El-Hajj, Pron B, et al. Outpatient parenteral antimicrobial therapy (OPAT) for the treatment of osteomyelitis: evaluation of efficacy,tolerance and cost. J Clin Pharm Ther. 2001;26(6):445-451.
8. Tice AD, Strait K, Ramey R, Hoaglund PA. Outpatient parenteral antimicrobial therapy for central nervous system infections. lin Infect Dis. 1999;29(6):1394-1399.
9. Matthews PC, Conlon CP, Berendt AR, et al. Outpatient parenteral antimicrobial therapy (OPAT): is it safe for selected patients to selfadministerat home? a retrospective analysis of a large cohort over 13 years. J Antimicrob Chemother. 2007;60(2):356-362.
10. Chemaly R, de Parres JB, Rehm SJ, et al. Venous thrombosis associated with peripherally inserted central catheters: a retrospective analysis of the Cleveland Clinic experience. Clin Infect Dis. 2002;34(9): 1179-1183.
11. Tice AD, Hoaglund PA, Nolet B, McKinnon PS, Mozaffari E. Cost perspectives for outpatient intravenous antimicrobial therapy. Pharmacotherapy. 2002;22(2, pt 2):63S-70S.
12. Rybak MJ, Lomaestro BM, Rotschafer JC, et al. Vancomycin therapeutic guidelines: a summary of consensus recommendations from the Infectious Diseases Society of America, the American Society of Health-System Pharmacists, and the Society of Infectious Diseases Pharmacists [published correction appears in Clin Infect Dis. 2009; 49(9):1465]. Clin Infect Dis. 2009;49(3):325-327.
13. Prabaker KK, Tran TP, Pratummas T, Goetz MB, Graber CJ. Elevated vancomycin trough is not associated with nephrotoxicity among inpatient veterans. J Hosp Med. 2012;7(2):91-97.
14. Cox AM, Malani PN, Wiseman SW, Kauffman CA. Home intravenous antimicrobial infusion therapy: a viable option in older adults. J Am Geriatr Soc. 2007;55(5):645-650.