Clinical and laboratory evaluation of the Shiley S-100-A oxygenator-heat exchanger.

A new oxygenator the Shiley S-100-A has been evaluated. It incorporates a heat exchanger based on an anodised aluminium tube which replaces the polyurethane coated tube of the previous S-100 model. Data from 46 patients perfused with the Shiley S-100-A were reviewed and compared with figures derived from a previous group of 225 patients in whom the S-100 model was used. The gas transfer capacity of the S-100-A model is very good and comparable to that of the S-100 oxygenator at a low gas flow/blood flow ratio. However both "in vitro" and "in vivo" studies confirmed the superiority of the heat exchange capacity of the S-100-A model. The times required for cooling (from 36.5 to 29.6 degrees C) and rewarming (from 29.6 to 37 degrees C) for an adult patient of average build were 9.1 and 26 minutes for the S-100 model and 6.7 and 15 minutes for the S-100-A model respectively. In a separate group of patients cooled to and rewarmed from 26 degrees C the cooling and rewarming times were 12.4 and 23 minutes respectively.