Cost effectiveness of 30-ml blood cultures 1 Cost-effectiveness of 30

Embed Size (px)

Text of Cost effectiveness of 30-ml blood cultures 1 Cost-effectiveness of 30

  • Cost effectiveness of 30-ml blood cultures

    1

    Cost-effectiveness of 30- compared to 20-milliliter blood cultures: a retrospective study 1 2

    Anita Cheruvankya, Thomas J. Kirna,b, Melvin P. Weinsteina,b, # 3 Department of Medicinea and Department of Pathology and Laboratory Medicineb, 4 Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA 5

    6 7 8 9 10 Running Head: Cost effectiveness of 30-ml blood cultures 11 12 13 14 #Address correspondence to Melvin P. Weinstein, weinstei@rwjms.rutgers.edu. 15 16 17 18 19 20 21 22

    JCM Accepted Manuscript Posted Online 21 October 2015J. Clin. Microbiol. doi:10.1128/JCM.02024-15Copyright 2015, American Society for Microbiology. All Rights Reserved.

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    on F

    ebruary 11, 2018 by guesthttp://jcm

    .asm.org/

    Dow

    nloaded from

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/http://jcm.asm.org/http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    2

    Abstract 23 Background 24 The importance of blood culture volume for detection of bloodstream infections (BSIs) is 25 documented. Recently, improved diagnostic sensitivity was demonstrated for 30 vs. 20 26 ml blood cultures (BCs) in adults (4). Hospitals receive higher reimbursement for patients 27 with documented septicemia. We determined the cost-effectiveness of 30 ml versus 20 ml 28 BCs using results from our institution and previously published data. 29 30 Materials and Methods 31 Positive BC results from 292 bacteremic episodes were reviewed. Costs of reagents, 32 equipment, phlebotomist and technologist time were determined. The Medical Records 33 Department provided Medicare reimbursement (MR) data for patients with selected ICD-34 9 codes. These data provided an estimate of the annualized increase in MR versus costs 35 associated with conversion to 30 ml BCs. 36 37 Results 38 MR for 464 annual primary BSIs was $24,808/episode. An expected 7.2% increase in 39 BSIs detected using 30 ml BCs would detect 34 additional cases annually and increase 40 MR by $843,472. Comparative MR data where septicemia complicated another diagnosis 41 were available for 4 ICD-9 codes: laparoscopic cholecystectomy, biliary tract disorders, 42 pneumonia, and cellulitis. Mean incremental MR was $9667 per episode, which projected 43 a $483,350 revenue increase annually. The annual cost associated with conversion to 30 44

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    3

    ml BCs was estimated to be $157,798. Thus, the potential net increase in hospital 45 revenue would be $1,169,031 for 30 ml vs. 20 ml BCs. 46 47 Conclusion 48 Our results suggest that conversion to 30 ml BCs may not only improve patient care by 49 detecting more BSIs but also substantially increase hospital revenue. 50 51 52 53 54 55 56 57 58 59 60 61 Introduction 62

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    4

    According to the CDC, sepsis affects more than 800,000 Americans annually and is the 63 ninth leading cause of disease-related deaths ( 2 ) . The Agency for Healthcare Research 64 and Quality lists sepsis as the most expensive condition treated in U.S. hospitals, costing 65 more than $20 billion in 2011( 2 ) . Blood culture (BC) remains the standard means of 66 detecting sepsis secondary to bloodstream infections (BSIs) (3). Prior studies have 67 shown that several variables influence the detection of bacteremia, including skin 68 preparation prior to venipuncture, the method and site of collection, the types of media 69 utilized, the number of cultures collected and, most importantly, the volume of blood 70 cultured (4). 71 All studies have indicated that as the volume of blood cultured increases, the likelihood 72 of detecting bacteremia also increases (5-9; 12, 15, 17-19). Patel et al. recently 73 demonstrated that two 30 ml BC sets with 3 bottles per set (2 aerobic and 1 anaerobic) 74 had improved pathogen detection for both non-conditional (not requiring detection in 75 more than one set to be considered positive) and conditional (requiring detection in at 76 least two positive blood cultures for classification as a pathogen and otherwise 77 categorized as a contaminant) pathogens with an improved yield of 7.9% and 11.0%, 78 respectively (4).. 79 However, , inoculation of only two 20-ml sets of BCs is standard practice in our 80 institution and we suspect at many other similar institutions (4). This practice is most 81 likely secondary to the notion that increasing the number of blood culture bottles per 82 episode of bacteremia will result in a significant increase in cost and inconvenience for 83 both the health care facility and the patient (21). 84

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    5

    85 The failure to obtain 30-ml of blood for each adult blood culture can result in lower 86 microbial recovery. Given the superior sensitivity of 30-ml BC sets compared to 20-ml 87 BC sets reported by Patel et al, we hypothesized that the institution of 30-ml BCs would 88 result in increased third party reimbursement for our hospital. Accordingly, we assessed 89 the costs and potential financial benefits associated with conversion from 20-ml to 30-ml 90 blood cultures in our institution. To our knowledge, this type of cost-benefit analysis has 91 not previously been reported. 92 93 94 95 96 97 98 99 100 101 102 MATERIALS AND METHODS 103

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    6

    Study Design. This study reviewed blood culture results from a retrospective cohort of 104 adult patients (18 years) from 1st January, 2012 to 1st March 2012 at Robert Wood 105 Johnson University Hospital (RWJUH) in New Brunswick, NJ. A blood culture (BC) 106 was defined as a set of two or three culture bottles which, when optimally filled with 107 blood, would have a total volume of 20-ml (2-bottle set) or 30-ml (3-bottle set).. 108 For each adult blood culture at RWJUH, twenty milliliters of blood was obtained 109 aseptically and equally distributed to one Bactec Plus Aerobic/F resin (hereafter referred 110 to as aerobic) bottle and one Bactec Lytic/10 Anaerobic/F (hereafter referred to as 111 anaerobic) bottle (Becton Dickinson, Sparks, MD) and incubated for 5 days in a 112 BACTEC FX instrument. This study was approved by the Rutgers Robert Wood Johnson 113 Medical School Institutional Review Board. 114 Microorganisms isolated from cultures were identified by standard techniques. Single 115 culture isolates of coagulase-negative staphylococci, diphtheroids and nonpneumococcal 116 alpha-hemolytic streptococci were classified as contaminants (4). However, in instances 117 where the same organism was isolated from 2 or more blood culture sets within a 48 hour 118 period, they were classified as true positives if they were the same species and had the 119 same biotype and antibiogram (13, 22). Pathogens not requiring two or more positive sets 120 to be classified as such (e.g., Staphylococcus aureus, Escherichia coli, Pseudomonas 121 aeruginosa) were also categorized as true positives (13, 22). 122 Most health care facilities including ours receive much of their reimbursement via 123 Medicare billing. In addition to Medicare, many other third party payers also reimburse 124 using a DRG based payment plan. Additionally, the ICD-9 codes 125

    on February 11, 2018 by guest

    http://jcm.asm

    .org/D

    ownloaded from

    http://jcm.asm.org/

  • Cost effectiveness of 30-ml blood cultures

    7

    bacteremia/septicemia/severe sepsis - all fall under the same classification of Major 126 Complications and Comorbid Conditions (MCC) for determination of their DRG weights. 127 128 Calculations. Medicare reimbursement data based on RWJUH institutional rates were 129 obtained from the Medical Records and Accounts Receivable departments during the 130 study period for all patients with a primary DRG diagnosis of 131 bacteremia/septicemia/severe sepsis and for several common ICD-9 codes: laparoscopic 132 cholecystectomy with and without MCC; kidney urinary tract infections with and without 133 MCC; disorders of the biliary tract with and without MCC; simple pneumonia with and 134 without MCC; other respiratory system diagnoses with and without MCC; cellulitis with 135 and without MCC; major joint replacement or reattachment of the lower extremities with 136 and without MCC; syncope and collapse with and without MCC and fever of unknown 137 origin . However, we include herein only four of these diagnoses (laparoscopic 138 cholecystectomy, disorders of the biliary tract, simple pneumonia and cellulitis) in our 139 calculations since they were the only ones that had septicemia as a secondary MCC 140 during the study period. 141 142 The cost of additional BC bottles, equipment, phlebotomist and technologist time and 143 effort were obtained from the Microbiology Laboratory. 144 145 These data then were used to provide an estimate of the annualized increase in MR and 146 costs associated with conversion to 30 ml BCs. For annualized calculations, data acquired 147 during the study period were multiplied by 4. 148

    on February 11, 2018 by guest

    http://j