Fluid resuscitation with deferoxamine hetastarch complex attenuates the lung and systemic response to smoke inhalation

Background. We determined the effect of infusing the iron chelator deferoxamine complexed to hetastarch on the degree of lung dysfunction and systemic abnormalities produced by a severe smoke exposure. Methods. Adult sheep were given a smoke exposure under anesthesia that produced a peak carboxyhemoglobin between 40% and 45%. Twenty-eight sheep were studied; eight were given smoke alone and resuscitated with sufficient lactated Ringer's solution to maintain baseline hemodynamics. Seven sheep were given a bolus plus 1 ml/kg/hr of a 10% deferoxamine-hetastarch solution for resuscitation; five were given hetastarch alone. The response was compared with eight controls during a period of 24 hours. Results. Smoke alone and smoke with hetastarch resulted in a shunt fraction of greater than 25% and a 50% decrease in compliance, severe airway inflammation, mucosal slough, atelectasis, and some alveolar edema. Increased lipid peroxides measured as malondialdehyde were present in airway fluid. In addition, oxygen consumption increased by 100% early after injury, net 24-hour positive fluid balance was almost 3 L, and a significant increase occurred in liver lipid peroxidation. The group given deferoxamine had a significantly attenuated lung response, with only modest airway damage, lung dysfunction, and minimal systemic changes including a net positive fluid balance of just over 1 L and no liver lipid peroxidation. Conclusions. An iron chelator deferoxamine complexed to hetastarch, given after a severe smoke exposure, significantly attenuates the airway and the systemic inflmmatory (oxidant) injury, indicating free iron release and subsequent increased oxidant activity to be a major etiologic factor.