Background: Life-threatening puncture-site bleeding and intra-variceal needle embedment are potential complications of glue therapy. Technical determinants to avoid these adverse events are: 1) usage of a compatible flushing liquid, prevent premature intra-catheter glue solidification, 2) estimation of dead space of the injection catheter, determine the quantum of flushing liquid to drive the glue into the varix and 3) estimation of the glue ‘solidification-time’, direct the ‘minimum needle-indwelling-time’ within the varix. 

Aim: To study these technical determinants in-vitro and to correlate the results with a clinical study

Methods:  In study 1, compatibility of normal saline, 5% dextrose and distilled water with glues from three bands was tested. In study 2, dead space of three injection catheters were estimated. In study 3 the solidification time of three NBC glues were determined. In study 4, the incidence of puncture-site bleeding and intravariceal needle embedment upon applying these technical determinantswere analysed.

Results: 5% dextrose and distilled water were compatible as flushing liquids and normal saline was not. The dead space of the studied injection catheters was either 1.4 or 1.6 ml. The glue solidification time ranged between 8 and 25 seconds. There was no incidence of puncture-site bleeding or intravariceal needle embedment when the in vitro results were applied in practice.

Conclusions: Normal saline is incompatible with glue and can cause premature glue solidification. Dead space of injection catheters is variable and should be factored in beforehand. Observing a minimum ‘needle-indwelling-time’ based on the glue solidification time is recommended.