A national evidence-based guideline for the management of community-acquired pneumonia (CAP) in children recommends blood cultures for patients admitted with moderate to severe illness. Our primary aim was to increase ordering of blood cultures for children hospitalized with CAP from 53% to 90% in 6 months. The secondary aim was to evaluate the effect of obtaining blood cultures on length of stay (LOS).
At a tertiary children’s hospital, interventions to increase blood cultures focused on 3 key drivers and were tested separately in the emergency department and inpatient units by using multiple plan-do-study-act cycles. The impact of the interventions was tracked over time on run charts. The association of ordering blood cultures and LOS was estimated by using linear regression models.
Within 6 months, the percentage of patients admitted with CAP who had blood cultures ordered increased from 53% to 100%. This change has been sustained for 12 months. Overall, 239 (79%) of the 303 included patients had a blood culture ordered; of these, 6 (2.5%) were positive. Patients who had a blood culture did not have an increased LOS compared with those without a blood culture.
Quality improvement methods were used to increase adherence to evidence-based national guidelines for performing blood cultures on children hospitalized with CAP; LOS did not increase. These results support obtaining blood cultures on all patients admitted with CAP without negative effects on LOS in a setting with a reliably low false-positive blood culture rate.
We would like to thank Drs. Quinonez and Garber for their thoughtful comments on our recent manuscript and appreciate the opportunity to further clarify our work. We agree that those embarking on improvement projects should consider value. The improvement project described in this article(1) is part of a larger institutional portfolio of improvement work centered on patients admitted with acute lower respiratory tract infections (LRTIs). Identification of the etiology of acute LRTIs is challenging. Most cases are viral(2) yet most children diagnosed with pneumonia receive antibiotics. Our efforts to increase the proportion of children with suspected bacterial pneumonia who had blood cultures performed were not conducted in isolation but rather carried out as one part of this larger portfolio of work. Related projects at our institution have included reducing resource utilization, such as using narrow rather than broad spectrum antibiotics, in children with pneumonia,(3) minimizing pulse oximetry in children with bronchiolitis,(4) and improving discharge processes.(5) The overall aim of this portfolio of work is reliable delivery of effective and efficient care to children with acute LRTIs. Part of our effort, which was not highlighted prominently in the publication, included encouragement of emergency department providers to not obtain blood cultures if they suspected a viral etiology of the acute LRTI. While performing chart reviews, we noted improved documentation around suspected viral etiology of acute LRTI, which allowed us to appropriately exclude these patients from the denominator of our outcome. We also increased the culture of collaboration between emergency medicine and hospital medicine by stressing the continuum of care between our two divisions. This approach allowed providers to limit blood cultures to the subset of patients in whom they suspected bacterial acute LRTI and, therefore, were planning to treat with antibiotics.
Drs. Quinonez and Garber raise an interesting point about other potential harms of increasing the proportion of patients with blood culture performed, other than the additional cost of increased length of stay which was not seen in our study.(1) It is worthwhile to note, possibly due to the multiple simultaneous improvement efforts around the population of patients admitted with acute LRTI, the length of stay for patients who had a blood cultured performed in our study (1.2 days) was lower than that previously reported by Mcculloh et al(6). The standard in our institution is to obtain all blood work, including blood cultures, at the time of intravenous catheter insertion, limiting the vast majority of patients to only a single venipuncture. While we were unable to determine the number of venipunctures required from the electronic medical record, this concern was never raised during our routine feedback sessions with nursing staff. Of the three patients with false-positive blood cultures, two of them did not have any change in their antibiotics (both received narrow-spectrum aminopenicillins) or additional blood cultures drawn. One patient who was discharged from the hospital prior to the blood culture result did return to the emergency department for a repeat blood culture and a single dose of intramuscular ceftriaxone pending identification and sensitivities from the initial blood culture. In additional analyses, we found no significant difference in direct costs between patients with and without a blood culture performed when adjusted for multiple potential confounders.(1)
We do believe that the nature of pneumonia management is changing. Our group and others have begun to focus on biomarker identification. Biomarkers can offer information about the host response to infection and pathogen activity within the host, features which can augment clinical decision-making and, ultimately improve our ability to predict which children are at low risk of bacterial infection and thus do not warrant blood cultures or other evaluation.(7) However, evidence in these areas is currently lacking. Rather than abandon blood cultures, we believe that the proportion of children classified as having suspicion for bacterial pneumonia will decrease as our ability to risk stratify or predict the likelihood of bacterial infections increases. Since we are only advocating obtaining blood cultures in this subset with suspected bacterial pneumonia, the proportion of patients who have blood cultures performed over time should continue to decrease as new methodologies are developed to better discriminate between viral and bacterial etiologies of acute LRTI. As microbial detection methods improve, the role of blood cultures, and with it our approach, will evolve over time.
References
1. Murtagh Kurowski E, Shah SS, Thomson J, et al. Improvement Methodology Increases Guideline Recommended Blood Cultures in Children With Pneumonia. Pediatrics. Apr 2015;135(4):e1052-e1059. Epub 2015 Mar 1016.
2. Jain S, Williams DJ, Arnold SR, et al. Community-acquired pneumonia requiring hospitalization among U.S. children. N Engl J Med. Feb 26 2015;372(9):835-845. doi: 810.1056/NEJMoa1405870.
3. Ambroggio L, Thomson J, Murtagh Kurowski E, et al. Quality improvement methods increase appropriate antibiotic prescribing for childhood pneumonia. Pediatrics. May 2013;131(5):e1623-1631. doi: 1610.1542/peds.2012-2635. Epub 2013 Apr 1615.
4. Schondelmeyer AC, Simmons JM, Statile AM, et al. Using Quality Improvement to Reduce Continuous Pulse Oximetry Use in Children With Wheezing. Pediatrics. Apr 2015;135(4):e1044-e1051. Epub 2015 Mar 1049.
5. White CM, Statile AM, White DL, et al. Using quality improvement to optimise paediatric discharge efficiency. BMJ Qual Saf. May 2014;23(5):428-436. doi: 410.1136/bmjqs-2013-002556. Epub 002014 Jan 002527.
6. McCulloh RJ, Koster MP, Yin DE, et al. Evaluating the use of blood cultures in the management of children hospitalized for community-acquired pneumonia. PLoS One. Feb 6 2015;10(2):e0117462. doi: 0117410.0111371/journal.pone.0117462. eCollection 0112015.
7. Florin TA, Ambroggio L. Biomarkers for community-acquired pneumonia in the emergency department. Curr Infect Dis Rep. Dec 2014;16(12):451. doi: 410.1007/s11908-11014-10451-11908.
Conflict of Interest:
None declared
We read with interest the quality report by Kurowski et al, titled "Improvement Methodology Increases Guideline Recommended Blood Cultures in Children With Pneumonia.1" We applaud the authors for their successful implementation and description of a complex project using quality improvement methods. The first question in the model for improvement is "What are we trying to accomplish?" Perhaps a second question should be added, "Why?" Kurowski et al cite compliance with the 2011 PIDS/IDSA guidelines and "to standardize managment1" to support their aim. In their project they increased the percent of blood cultures performed in children admitted for community acquired pneumonia (CAP) from 53% to 79%.
While the PIDS/IDSA CAP guideline recommends blood cultures in children admitted with moderate to severe CAP, the evidence cited for this recommendation is weak. In fact, as Kurowski et al acknowledge, research published since guideline release, further questions the utility of blood cultures. One thing, however, that all these studies agree on is that the percent of pathogenic bacteria recovery is usually less than 5%, and in most the actionable information obtained is even lower. Most telling is the authors' comparison of their study to Heine et al2. In that article researchers studied the effectiveness of institutional guidelines in DECREASING the frequency of unnecessary blood cultures compared to national CAP guidelines. They studied a similar number of patients, 330; found the same ratio of pathogens to contaminants, 1:1 and an almost identical rate of true bacteremia, 1.5%. All 5 patients with bacteremia had radiographic evidence of effusion or empyema and were admitted to intensive care or described as being septic, thus meeting their institutional criteria to obtain blood culture. Adoption of institutional guidelines could have reduced the frequency of blood cultures from 47% to 26% without missing any true positives.
Interestingly, the authors of the current study had institutional guidelines similar to the ones proposed in Heine et al, and they were working! In fact the authors, through their intervention, managed to decrease their percent of true-positive blood cultures from an unusually high rate of 6.3% pre-intervention to a negligible rate of 1.3% by drawing more blood cultures.
After adjusting for covariates, the authors did not find an increased length of stay in patients with blood cultures versus those without, thus we assume they conclude lack of harm. However, there are other harms of obtaining unnecessary blood cultures: increased pain and discomfort (the authors do not describe how many extra venipunctures it took to improve compliance), costs, possible exposure to broad spectrum antibiotics and increased testing including repeat cultures.
Again we applaud the authors for demonstrating how a multimodal, complex quality improvement project to increase adherence to national guidelines can be successfully implemented and described. We question however, the value of this particular endeavor. The authors have managed to increase costs at the expense of dubious patient benefit. They have exposed some of the weaknesses of the current enthusiasm for quality improvement, and remind us to consider value before embarking on that next PDSA.
1. Kurowski EM, Shah S, Thomson J et al. Improvement Methodology Increases Guideline Recommended Blood Cultures in Children With Pneumonia. PEDIATRICS. 2015; 135(4):e1053-e1059. 2. Heine D, Cochran C, Moore M, Titus MO, Andrews AL. The prevalence of bacteremia in pediatric patients with community-acquired pneumonia: guidelines to reduce the frequency of obtaining blood cultures. Hosp Pediatr.2013;3(2):92-96.
Conflict of Interest:
None declared