setting
This study was conducted at the Aichi Cancer Center (ACC), a 500-bed tertiary care facility in Aichi Prefecture. The center has 23 departments and receives approximately 11,000 patients annually. Specifically, plastic and reconstructive surgery, blood and cell therapy, thoracic surgery, thoracic oncology, gastrointestinal surgery, gastroenterology, orthopedics, head and neck surgery, breast oncology, neurosurgery, urology, and gynecology. Fifteen clinical departments, including oncology and radiology, are in charge of inpatients. Oncology, Diagnostic Radiology and Interventions, and Clinical Oncology. The Antimicrobial Stewardship Team (AST) consists of one ID specialist (increased to two from April 1, 2021), one pharmacist, two laboratory technicians, and one infection control nurse.
research design
This was a single-center, retrospective, observational study conducted over a 48-month period from April 1, 2018 to March 31, 2022.
intervention
The intervention evaluated in this study was implemented in two phases:
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(1)
Phase 1: Pre-intervention period (April 1, 2018 to March 31, 2020).
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(2)
2nd period: Introduction of ASP and establishment of ID consultation service (April 1, 2020 – March 31, 2022)
Inclusion criteria
Inclusion criteria were all hospitalized patients with positive blood cultures between April 1, 2018 and March 31, 2022.
ASP
On weekdays, ID specialists promptly communicated positive blood culture results to the attending physician team to ensure appropriate empiric treatment. Over the weekend, the laboratory or ID specialist did not communicate the positive blood culture results to the primary care team, but did so the following weekday.case Staphylococcus aureus (Staphylococcus aureus) or Candida If a species was detected, an ID consultation was suggested and the patient was examined at the bedside.
In addition, three weekly audits of (i) specific antimethicillin resistance agents were conducted for all patients at the AST conference; Staphylococcus aureus Drugs – vancomycin, teicoplanin, daptomycin, linezolid. (ii) Certain broad-spectrum antibiotics – cefepime, cefozopran, piperacillin-tazobactam, imipenem-cilastatin, meropenem, and doripenem. Patients who had already received an ID consultation were excluded from the audit. For the AST conference, pharmacists retrieved data from the ACC’s electronic medical record system for patients who received specific antibiotics. The laboratory technician shared the latest microbiological information about these patients with other members of her AST. After confirming the presence of drug-resistant microorganisms in the patient’s body, the infection control nurse immediately alerted the management of the patient’s hospital ward, who took the necessary infection control measures. The ID experts oversaw the comprehensive management of each expert’s role in this process. All cases reviewed at the conference were recorded in the electronic medical record. For patients determined by the AST to require a change in antimicrobial therapy or additional culture testing due to insufficient testing, feedback will be provided to the attending physician team on the day of the audit by telephone or by note in the patient’s medical record. It was done. All audited patients were monitored every weekday until completion of specific antimicrobial therapy or during the follow-up period required by the AST. The AST contacted the attending physician team when necessary. From April 2021, audits have been expanded to all weekdays and fluoroquinolones have been added to the list of targeted antimicrobials. For patients who are determined to require a bedside evaluation by an ID specialist because it is difficult to determine the diagnosis and treatment of ID based solely on review of medical record information by the AST conference, the ID specialist contacted his physician team and suggested an ID consultation.
ID consultation service
A dedicated ID specialist provided patient consultation throughout the week from the 15 aforementioned primary care physician teams.
Data collection
For all patients with a positive blood culture, the following information was collected from the ACC electronic medical record system for each episode: age, gender, medical department, date of blood culture, body fluid collection, microbial detection, diagnosis, and 30 days. all-cause mortality rate, whether the ID specialist provided feedback. The ACC database provided information on specimen submission counts, AS reviews, and ID consultations. We accessed these data on August 5, 2023 for research purposes.
meaning
Diagnosis was determined from the description in the medical record, and cases without description were considered unknown. If the focus of infection was clear, the diagnosis was not classified as febrile neutropenia, regardless of the presence of neutropenia. The term “polyinfection” was defined as the presence of two distinct ID conditions for which the cause of bacteremia was not clearly determined. The 2-set blood culture rate was defined as (number of 2 sets/total of sets) × 100, and the positive blood culture rate was defined as (number of positive sets/total of sets) × 100. Blood culture-positive episodes with unknown results were excluded from all-cause 30-day mortality calculations. Respiratory specimens included sputum, pharyngeal mucus, nasal mucus, oral mucus, lung tissue, and bronchial lavage fluid. Gastrointestinal specimens included stool, bile, and pancreatic juice. The urogenital specimen consisted of urine and vaginal secretions. Aspirate fluid specimens included pleural fluid, ascites fluid, spinal fluid, joint fluid, and bone marrow fluid. Other materials include catheter tip and wound cultures, drain cultures, and cultures obtained from various sources.
Main outcome measures
The primary outcome was the proportion of patients with unknown diagnosis documented in the medical record for each positive blood culture.
Secondary outcome measurements
Secondary outcomes assessing the impact of ASP and ID consultation on diagnostic testing included (i) the number of culture specimens of each type submitted per 1000 patient-days of hospitalization, (ii) two-set blood culture rate, and (iii )Positive blood culture rate. Inpatient culture specimens include blood, respiratory, gastrointestinal, and genitourinary specimens, aspirate fluid, other materials, and total specimens. Culture specimens used for screening were excluded from the study. Furthermore, to determine the prognostic impact of our intervention, we evaluated her 30-day all-cause mortality in patients with blood culture-positive episodes. Second or subsequent episodes of bacteremia in the same patient during the study period were included in mortality. Additionally, mortality rates include all deaths, including those from cancer and ID.
statistical analysis
Pearson’s chi-square test and Fisher’s exact test were used for categorical variables, and Wilcoxon rank sum test was used for analysis of continuous variables. Primary endpoints and 30-day mortality were compared between pre- and post-intervention periods (April 1, 2018 to March 31, 2020 and April 1, 2020 to March 31, 2022, respectively). Secondary endpoints other than 30-day mortality were examined using an interrupted time series. Due to the exploratory nature of this study, no adjustment was made for multiple comparisons. A p value less than 0.05 was considered statistically significant. Analyzes were performed using R software version 4.2.0 (R Foundation for Statistical Computing, Vienna, Austria) and SPSS version 28 (IBM Corp., Armonk, NY, USA).
ethical considerations
This study was approved by the Institutional Review Board of ACC Hospital (approval number: 2023-0-161) and was conducted in accordance with the principles of the Declaration of Helsinki. Because this study used only data collected in a clinical setting, the requirement for informed consent was waived by his ACC Hospital Institutional Review Board.