Examining the Impact of Enhanced Infection Prevention Measures on HAIs, Including CLABSIs

Numerous studies have been conducted about the health care-association infections (HAIs) during the COVID-19 pandemic. In a new study conducted by investigators at The University of Texas MD Anderson Cancer Center to research how COVID-19 precautions affected the incidence of HAIs, central line-associated bloodstream infections (CLABSIs), multidrug-resistant organisms (MDROs), and 3 others across different wards in the Center. The study “The Impact of the COVID-19 Pandemic on Hospital-Acquired Infections at a Comprehensive Cancer Center” was published in the American Journal of Infection Control.

To learn more about the study’s findings, Infection Control Today® (ICT®) interviewed Amy Spallone, MD, assistant professor of infectious diseases in Infection Control and Employee Health, MD Anderson Cancer Center, and one of the study’s authors.

Study Background:

ICT: Can you provide an overview of the study’s objectives and what prompted your team to conduct this research?

Amy Spallone, MD: At the start of the pandemic, we made several rapid changes at our institution to ensure our patients and staff were protected. Our infection preventionists conduct extensive surveillance, even before the pandemic, so we knew by looking at our internal data that our HAI rates started to change after the start of the pandemic and after implementing significant institutional changes in our IPC protocols. To better understand what we were seeing, we decided to compare our HAI rates before and after the start of the pandemic. We wanted to know what impact our enhanced IPC measures were having on our HAI rates, so we looked at and calculated the rates of 6 HAIs among the approximately 30,000 patients admitted annually at the cancer center from September 2016 through March 2022: Clostridioides difficile infection, MDROs, respiratory viral infections (RVIs) and device-related infections—catheter-associated urinary tract infections (CAUTIs), CLABSIs, and ventilator-associated events (VAE).

ICT: What key infection prevention and control (IPC) measures were implemented at MD Anderson during the COVID-19 pandemic?

AS: At the onset of the pandemic, we established what we termed our “pillars of priority” in the institution. They included making rapid, high-volume COVID-19 testing available to all our patients and staff. We also wanted to ensure that we had a stable supply chain of PPE so that all our staff and operations were properly protected, and we made masking mandatory in all areas of our medical campus. To control movement in and out of our institution, we limited our points of access into buildings and limited the number of visitors, researchers, and non-patient care staff on campus. Lastly, we established our COVID-19 care model. This included cohorting COVID-19 positive patients in the hospital by creating a dedicated COVID-19 unit with dedicated staff. Cancer didn’t take a vacation just because a worldwide pandemic was happening, so we also created special pathways to allow outpatient COVID-19 positive patients to continue urgent necessary treatments (eg surgeries, radiation, imaging) and receive lab draws/transfusions/hydration/chemo in a secure quarantine outpatient unit.

Results and Impact on HAIs:

ICT: What were the most significant findings regarding the impact of enhanced IPC measures on HAIs at MD Anderson?

AS: As a reminder, NHSN’s HAI reports for acute care hospitals across the United States noted a significant increase in the rates of CLABSIs, CAUTIs, and VAEs, recorded during the third and fourth quarters of 2020 compared to corresponding quarters in 2019. However, we saw a significant decrease in our CLABSI and CDI rates, which differs from what other large centers have published for the same period. We also saw a huge drop in total RVI since the start of the pandemic.
We were surprised to see our MDRO rates, which showed the rates in the COVID-19 wards were more than five times higher than in the other inpatient wards (1.99 vs. 0.35 with an IRR of 5.77). Our MDRO rates went unchanged during the pandemic in our non-COVID wards.

ICT: Can you elaborate on how these measures affected C difficile infections, CLABSI, and RVIs?

AS: For C difficile rates, I think we can attribute the significant reduction in our center to the increased emphasis on PPE use, hand hygiene compliance, and decreased visitor traffic. A similar decrease was seen across the country after the onset of the pandemic. A decrease in nosocomial RVIs was a welcome consequence for our vulnerable cancer and hematopoietic cell transplant patient populations. This decrease in rates of nosocomial RVIs was also noted in other centers worldwide. We know that the seasonal respiratory viruses (RSV, influenza, Parainfluenza virus (PIV)) essentially disappeared at the heights of the pandemic. This is most likely from several mitigation tactics implemented at the individual, community, national, and even international levels. We stopped global travel, implemented stay-at-home orders, everyone put on masks, and individuals quarantined if they were symptomatic. These all led to an almost immediate drop in respiratory viruses worldwide. Stopping community transmission meant we were stopping respiratory viruses from entering our hospitals and preventing our patients from being exposed. In our cohort of patients, the decreased rate of CLABSIs may be explained by our record of accomplishment of central line bundle compliance noted to be at 100% as of September 2022 and central line placement and maintenance being exclusively done by trained and experienced staff who routinely underwent institutional education and are well versed with the central venous catheter insertion bundle. This included our staff overseeing and caring for our COVID-19+ unit patients.

Comparison of HAI Rates:

ICT: How did the incidence rates of HAIs during the pandemic compare to those before the pandemic (prepandemic)?

AS: The incidence rates for catheter-associated bloodstream infections (CLABSI) (0.51 to 0.322 per 10,000 patient days), health care facility-onset C difficile infection (6.58 to 4.31 per 10,000 patient days), and total respiratory viral infections (5.24 to 1.90 per 10,000 patient days) significantly decreased in our hospital when we compared the rates prepandemic to during the pandemic. This was in stark contrast to reports from other centers, where the rates of CLABSI increased during the pandemic. The rates of other device-related infections, such as CAUTI and VAE, had decreased trends in rate but did not meet statistical significance. Of interest, we saw that the rates of infections due to MDROs stayed stable in the hospital but increased in the COVID-19 unit amongst cohorted patients.

MDRO Rates:

ICT: Could you discuss the impact of IPC measures on MDRO rates among patients, especially in COVID-19 wards?

AS: Despite patients with COVID-19 being cohorted in a single unit with limited interactions with visitors and health care staff, we saw an increase in the rates of MDROs in this unit, whereas the rates in our center stayed the same. It’s not clear if our infection prevention and control (IPC) measures affected this; however, we did see an overall rise in the use of IV antibiotics. Our patient population often lacks source control due to contraindications to procedures and severe neutropenia. The only strategy is the medical management of these complicated infections, which may predispose to MDRO development. As previously published, the rate of MDROs increases with increased antibiotic use. We do see that despite increased antibiotics use, our C difficile rates decreased. I suspect that the MDRO arose from an endogenous or poorly controlled source of infection in our cancer patients and was unrelated to IPC.

CLABSI Bundle Adherence:

ICT: You mentioned 100% CLABSI bundle adherence in September 2022. Could you explain what this entails and how it contributed to reducing CLABSI rates?

AS: Our vascular access and nursing teams are educated and trained on the central line bundles, designed to ensure line insertion and maintenance are consistent across our care teams. The elements include:

• Hand hygiene performed.
• The insertion site was prepped with appropriate disinfectant (CHG), and the skin prep agent was completely dried before the procedure.
• Aseptic technique practiced.
• Maximum sterile barriers were used.
• Sterile dressing applied.

During the pandemic, we continued to provide all staff with access to PPE and that they had the supplies they needed to ensure they were maintaining our patients’ central lines in accordance with hospital policy.

ICT: Were specific strategies or practices implemented to achieve this level of adherence?

AS: Maintaining good staff education and low turnover rates during the pandemic had a lot to do with achieving our [adherence]. Our nurses are experts in cancer patient care, and they understand how vital it is to preserve the sterility of our patients’ central lines.