Aluminium release and fluid warming: provocational setting and devices at risk

Abstract

Background: Fluid warming, recommended for fluid rates of > 500 ml h^-1, is an integral part of patient temperature management strategies. Fluid warming devices using an uncoated aluminium containing heating element have been reported to liberate aluminium resulting in critical aluminium concentrations in heated fluids. We investigated saline solution (0.9%), artificially spiked with organic acids to determine the influence of fluid composition on aluminium release using the uncoated enFlow® device. Additionally, the Level1® as a high volume fluid warming device and the ThermoSens® device were investigated with artificial spiked fluid at high risk for aluminum release and a clinically used crystalloid solution.

Results: Saline solution spiked with lactate more than acetate, especially at a non neutral pH, led to high aluminium release. Next to the enFlow® device, aluminium release was observed for the Level1® device, but not for the coated ThermoSens®-device.

Conclusion: Uncoated aluminium containing fluid warming devices lead to potentially toxic levels of aluminium in heated fluids, especially in fluids with non-neutral pH containing organic acids and their salts like balanced electrolyte solutions.

Keywords: Fluid warming; Hypothermia; Prevention; Warming techniques.

Fig. 1

Mean (SD) aluminium concentration over the time (BL – Baseline; 0 to 60 min; each six measurements) for the enFlow® (Vital Signs, Inc., aGE Healthcare Company, Totowa New Jersey, USA) with different fluids as follows: ① saline 0.9 % ② saline 0.9 % with 50 mmol acetate ③ saline 0.9 % with 50 mmol lactate ④ saline 0.9 % with 50 mmol lactate at pH 4.0 ⑤ saline 0.9 % with 50 mmol lactate at pH 9 ⑥ saline 0.9 % at pH 9. Each six measurements

Fig. 2

Mean (SD) aluminium concentration over the time (BL – Baseline; 0 to 60 min; each six measurements) for the Level 1® (H-1025 and DI-300 disposable, Smith medical, Minneapolis, USA) with different fluids as follows: ⑦ saline 0.9 % with 50 mmol lactate ⑧ saline 0.9 % with 50 mmol lactate at pH 9

Fig. 3

Mean (SD) aluminium concentration over the time (BL – Baseline; 0 to 60 min; each six measurements) with balanced electrolyte solution Sterofundin 1/1 E ISO: ⑨ EnFlow® (Vital Signs, Inc., aGE Healthcare Company, Totowa New Jersey, USA) ⑩ Level 1® (H-1025 and DI-300 disposable, Smith medical, Minneapolis, USA)