1997 OPEN FORUM Abstracts
LABORATORY EVALUATION OF CLOSED SUCTION CATHETER DEVICES
F.W. Johnson, RCP K. Kinninger, RCP, E. Bak, M.Sc., D.M. Burns, M.D., University of California, San Diego Medical Center.
Introduction: A Closed Suction Catheter (CSC) device is a closed-circuit, multiple-use, in-line tracheal suctioning system designed for use in the patient requiring mechanical ventilation. While previous in-vivo studies have reported the patient benefit of CSC devices, the in-vitro performance characteristics of CSC devices have not been tested. We evaluated four CSC devices in the laboratory to determine whether changes in airflow, secretion fluid levels, and positive and negative pressures influence the device performance characteristics. Methods: The six CSC devices selected for testing included the Cath-Guide, swivel (HS) and tee (HT) (Hudson RCI, Temecula, CA), Trach Care, swivel (BS) and tee (BT)(Ballard Medical Products, Draper, UT), Steri-Cath, tee (ST) (Smith Industries Medical Systems, Keene, NH) Isocath, swivel (VS)(Vital Signs Inc, Totowa, NJ). The following performance tests were conducted with three of each CSC devices: 1) A static pressure leak test across the patient connector of the CSC over an incremental pressure range of 0.5 to 14.0 Kpa, 2) The NPB 7200 Quick Extended Self-Test (QEST) was performed with the CSC device placed in the circuit to determine whether the CSC met the pass or fail criteria, 3) A pressure leak test was performed across the catheter tip to the suction control valve of the CSC when pressurized to 1.4 Kpa, 4) A vacuum surge pressure test was performed across the catheter tip to the suction control valve of the CSC when a vacuum of 12.0 Kpa is applied to determine the peak pressure and rise time 10-90% sec., 5). The patient connector resistive back pressure was measured at flow rates 30 to 120 L/min, 6) A simulated 24 hour secretion clearance test was performed to quantify the amount of simulated secretions fluid removed with a CSC at a vacuum pressure of 12.0 Kpa during a simulated 24 hour usage. Results:1) Static Leak Test, leaks were detected at 3.0, 6.0, 14.0 and 14.0 Kpa respectively for BT and HT. No leaks were detected with the ST. Leaks were detected at 0.5, 1.5, 3.0 ,6.0, 14.0 and 14.0 Kpa respectively for VS and BS. No leaks were detected with HS, 2) QEST Test, all CSC devices successfully passed the QEST except for the VS device, 3) Pressure Leak Test, all CSC devices exhibited no measurable leaks except for the VS device, 4) Vacuum surge pressure test, the peak pressure/ rise times were 11.8,/1.5, 13.0,/0.1, 12.7,/0.1, (Kpa, 10-90% sec.) respectively for HT, BT and ST and 12.0/1.6, 13.0/.0.3, 13.0,/0.1 (Kpa, 10-90% sec.) respectively for HS, BS, and VS, 5) Patient Connector Resistance Test, measured the back pressures was 0.23, 0.30, 0.73 (cmH2O) respectively for HT, BT, ST and 0.75, 0.43, 0.55 (cmH2O) respectively for HS, BS, VS devices, 6) Simulated 24-Hour Secretion Clearance Test, the amount of fluid measured was 33.6, 35.9, 39.1 ml. respectively for HT,BT,ST and 35.5, 35.6, 30.0 ml. respectively for HS, BS, VS devices Conclusion: Currently, neither quality control standards or testing standards have established for CSC devices. With this in mind, we designed this study to evaluate commercially CSC devices available at this time. Our testing of the CSC devices found the performance characteristics to be equivalent, excluding the VS device, which did not perform equivalent to the other devices, tested. Further studies will be required to support these findings in the clinical environment.