Several infections with nontuberculous mycobacteria have implicated heater-cooler units.
Most cases have involved cardiothoracic surgery but theoretically could involve any patient exposed to one of these units.
Heater-cooler units are used to raise or lower the patient’s body temperature. The implicated area is the water bath to the unit.
Risk factors for infection:
(1) failure to clean and disinfect the unit
(2) failure to follow manufacturer’s instructions when cleaning and disinfecting
(3) use of tap water to fill the water reservoir
(4) venting the unit’s exhaust into the surgical field
(5) failure to monitor the water bath for turbidity, discoloration or other sign of bacterial overgrowth
(6) failure to add chemicals to suppress bacteria and fungal growth (if recommended by manufacturer)
(7) failure to perform regular maintenance and performance checks
A patient who develops an infection after cardiothoracic surgery or other procedure using a heater-cooler device should be cultured for nontuberculous mycobacteria. The water bath and unit should also be cultured.
Differential diagnosis: infection due to Pseudomonas or other water-borne bacteria
