Since the implementation of the LifeshieldR (LAV) needleless primary intravenous tubing system (Abbott Laboratories) at Vancouver Hospital and Health Sciences Centre (VHHSC), case reports of cracked LAV units and leaks have been anecdotally linked to the use of propofol in the operating room setting. A preliminary investigation by Abbott Laboratories showed that after 24 hours of exposure to propofol, 31 of 32 LAV units cracked upon attachment of a male adapter, and 20 of 32 units cracked at 12 hours after a 5 minute exposure to propofol.
The objective of this study was to validate the observations by the manufacturer and determine whether or not exposure to propofol with subsequent manipulation by saline syringe flushing and attachment of a male adapter would cause cracks or leaks in the LAV units.
A major Canadian tertiary care teaching hospital.
Prospective observational study.
Ten LifeshieldR (LAV) units (Abbott Laboratories Lot No. 62-032 NS) were randomly drawn from hospital supplies and inspected for cracks and other visible defects. Following this inspection, the units were injected with 4-5 mL of propofol (Abbott Laboratories – Lot No. 46-839Z7), a male adapter was attached, and they were allowed to sit undisturbed at room temperature for 24 hours. The LAV units were then inspected at 2, 4, 6, 14, 16, 20, and 24 hours for signs of cracks or leaks. At 24 hours, a 12 mL leur-lock syringe with a male adapter was directly attached onto each LAV unit to flush with 20 mL of normal saline solution. The units were inspected immediately after the flush, then allowed to stand undisturbed at room temperature for a further 24 hours. At the end of this period, a final visual inspection of the units was undertaken.
Main Outcome Measures
The primary outcomes of this study were visual evidence of cracks or leaks at baseline, anytime throughout the 24-hour exposure to propofol, immediately after flushing the units, and at 24 hours post-flushing.
At baseline, 7 of the 10 units had visual collar markings that were deemed to be inclusions, not cracks. No cracks or leaks developed in any of the 10 units inspected during the experiment. Any visual markings on the units were unchanged after exposure to propofol.
We were unable to duplicate the findings of the manufacturer and found no evidence that prolonged propofol exposure to Lifeshield (LAV) units causes cracks or leaks, or alters pre-existing visual markings on the units. We hypothesize that excessive lateral force, excessive torque or other factors may be the primary cause of the reported cases of device failure at this hospital. In contrast, the manufacturer has concluded that the lipid-based propofol solution is reacting with the plastic LAV components and has identified that they are initiating a corrective plan to convert to an alternate plastic material that is compatible with lipid-type solutions. In the interim, Abbott recommends that Clave-type ports be used as the material of this type of port is apparently compatible with lipids.