(83) Performance Improvement Initiative to Decrease QNS rates for Sweat testing at a Community Hospital

Background: Sweat chloride testing remains an integral part of diagnostic testing for Cystic Fibrosis. We have a robust regional adult screening program for CF at our center and Pacific Diagnostic Laboratory (PDL) is an accredited for Sweat testing site. The recommended standard quantity not sufficient (QNS) rate for patients >3 months of age is < 5% and the suggested goal for patients < 3 months is < 10% QNS rate. A quality improvement (QI) program for sweat testing was instituted to improve QNS rates to the acceptable standards set by the CF foundation.

Methods: Santa Barbara Cottage Hospital CF team and PDL participated in the quality improvement initiative. Analysis included all sweat tests performed from January 2019 through April 2022. Sweat test samples before 1/24/20 were collected using the WesCor Macroduct Collection system and analyzed using Siemens Dimension Vista analyzer. Changes implemented to reduce QNS rates were: 1. Sweat samples after 1/24/2020 were collected using Macroduct Advanced Sweat Collection System Model 3710 and analyzed with digital ChloroCheck Chloridometer (ELITechGroup Inc.) after 1/24/2020. 2. Sweat from both arms was collected and resulted after 10/1/2021. 3. Creation and updating of Sweat Chloride Testing Brochure (9/2021) including information/instructions to patients to be well hydrated before the appointment 4. Instructions on the appointment scheduler about the importance of hydration prior to appointments (9/2021) 5. Appointment reminder call was made to patients emphasizing being well hydrated for their appointment (9/2021) 6. Water made available to the patient during the procedure for hydration (9/2021)

Results: Sweat testing was performed on 200 patients, 120 Male: 80 Female, 63 children and 137 adults. Prior to instituting the new method (2019- 1/24/2020) our QNS rate was 6%. After implementation of the new sweat collection method and analyzer on 1/24/2020, our QNS rate decreased to 5% for all the patients tested till 4/1/2022. After implementation of Double collection method on 10/2021 our QNS rates decreased to 0% based on the definition of QNS in the sweat testing guidelines published by the CF foundation

Conclusions: Improvement was observed in QNS rates after sequential implementation of the change measures/PDSA cycles in January 2021 in all patients referred for sweat testing to our lab. Our data confirms that performing sweat collections in both arms resulted in the most significant reduction in QNS rates though the other changes implemented sequentially probably contributed to the improvement. Only one patient was < 3 months of age. We will closely monitor the performance of our sweat testing procedure and QNS rates with SDSA cycles and institute change measures as necessary

Acknowledgements: Allison Reitz

References: Sweat testing Standards for CFF accredited Care Centers, Revised January 10, 2019

Farrell PM, White TB, Ren CL, Hempstead SE, Accurso F, Derichs N, Howenstine M, McColleySA, Rock M, Rosenfeld M, Sermet-Gaudelus I, Southern KW, Marshall BC, Sosnay PR. Diagnosis of Cystic Fibrosis: Consensus Guidelines from the Cystic Fibrosis Foundation. JPediatr. 2017 Feb;181S:S4-S15.e1.PMID: 28129811

LeGrys VA, Yankaskas JR, Quittell LM, Marshall BC, Mogayzel PJ, Cystic Fibrosis Foundation.Diagnostic Sweat Testing: The Cystic Fibrosis Foundation Guidelines. J Pediatr. 2007 Jul;151(1):85-9.PMID: 17586196



Diagnostic Sweat Testing: The Cystic Fibrosis Foundation Guidelines. Vicky A. Legrys et al