In Vitro Study Assessing the Technical Feasibility of Using 3-F Inner Dilators for Imaging

Purpose

The 3-F inner dilators from three brands of micropuncture kits with slightly different designs were studied to identify the maximal flow rate of contrast medium infusion in hopes of identifying a safe range for the delivery of contrast media.

Materials and Methods

The inner dilators from three micropuncture kit manufacturers were tested. To assess maximum flow rates, each inner dilator was subjected to repeated contrast medium infusions at sequentially higher flow rates until it failed or reached maximal rate limits of the autoinjector. After a thorough inspection of each failed dilator, results for flow rates and pressures at failure were collected.

Results

All inner dilators were capable of achieving flow rates of at least 6 mL/sec at an average pressure of 258 psi. None of the inner dilators ruptured or resulted in a distal embolic event in our vessel model. Two dilators from the same manufacturer reached maximal rate limits of the autoinjector and did not fail.

Conclusions

The use of the inner dilators from these micropuncture kits for nonselective angiography at rates at or less than 6 mL/sec appears technically feasible. Although it appears to offer angiographers and patients a quicker and perhaps safer alternative than conventional upsizing to catheters with larger lumens, additional experimental and clinical trials are necessary to fully endorse this in clinical practice.