Resuscitation of the Thermally Injured Patient

[Acute respiratory insufficiency in burn patients from smoke inhalation]

Respiratory injuries by smoke inhalation are one of the most frequent reasons for acute respiratory failure in burn victims. They are most often of chemical origin and are responsible of a 20 to 70% increase of the mortality compared to the mortality of patients with similar burn injuries, but without inhalation lesions. They are often associated to a certain degree to other factors of acute respiratory failure: superior air way obstruction by oedema in face and neck burns, thoracic expansion hindrance due to thoracic burns, lung trauma lesions by blast injury. The generalized inflammatory reaction due to the extent of burns and an initial inadequate resuscitation are worsening factors. The inflammatory process may be responsible of lung injuries similar to those induced by smoke inhalation, even when there is no inhalation. The treatment remains symptomatic and based on the oxygen therapy, mechanical ventilation, prevention of infections and maintain of homeostasis by hydroelectrolytic adequate resuscitation. The nitric oxyde associated to the almitrin allows in a certain number of cases to minimize intra pulmonary shunting and to normalize the VA/O ratio. The development of treatments allowing to modulate inflammatory mediators may lead to news therapies in the future.

Burn resuscitation with two doses of 4 mL/kg hypertonic saline dextran provides sustained fluid sparing: a 48-hour prospective study in conscious sheep

BACKGROUND

The large fluid volumes usually required for burn resuscitation can be suppressed for 8 to 12 hours by intravenous infusion of 4 mL x kg(-1) hypertonic saline dextran (HSD) 1 hour after burn. We hypothesized that a double (8 mL x kg(-1)) dose of HSD or two repeated doses of 4 mL x kg(-1) could enhance or prolong the volume sparing.

METHODS

We produced a full-thickness flame burn covering 40% of the body surface on 18 anesthetized sheep. One hour after the burn, the animals were awake and resuscitated with either (1) lactated Ringer's solution (LR) only, (2) 8 mL x kg(-1) HSD followed by LR, or (3) 4 mL x kg(-1) HSD followed by LR, with a second dose of 4 mL x kg(-1) HSD administered when net fluid accumulation increased to 20 mL x kg(-1). For all regimens, infusion rates were adjusted to produce a urine output of 1 to 2 mL x kg(-1) x h(-1).

RESULTS

Animals resuscitated with only LR required fluid volumes identical to that predicted by the Parkland formula for the first 12 hours. Infusion of 8 mL x kg(-1) HSD initially created a net fluid loss (urine output > infused volume), followed by a rebound fluid requirement eventually equaling that of animals treated with LR only. Animals treated with two separate doses of 4 mL x kg(-1) HSD generally did not experience a net fluid loss or a rebound fluid requirement. Also in the HSD x 2 group, peak and net fluid accumulation was less than that of the other two groups from 18 hours through 48 hours, although the difference was not significant.

CONCLUSION

An initial 4 mL x kg(-1) dose of HSD reduces fluid requirements early after burn, and a second dose administered after an appropriate interval may prolong volume sparing through 48 hours. An 8 mL x kg(-1) continuously infused initial dose was without prolonged fluid sparing effect. The volume-sparing effect of HSD is thus dependent on all of the following: dose, dosing interval, and infusion rate.

Effect of heta-starch colloidal solutions on reticuloendothelial phagocytic system (RES) function in burned and infected rats

The biodistribution of the plasma expander colloidal solution, heta-starch (HES), has been examined in rats, subjected to thermal injury or sepsis. The ability of these solutions to alter RES phagocytic function of [99mTc]-sulphur colloid ([99mTc]SC) uptake in vivo has been examined. The biodistribution of radiolabelled HES has been determined in normal rats. The HES colloidal solution has no deleterious effect upon RES function in vivo in the thermally injured animals or the septic animals as compared to sham controls. In addition, the HES colloidal solution seemed to be distributed primarily within the liver, spleen and kidney, with a small amount residing in the lung. Thermal injury did not increase the uptake of this material by the lung. These results suggest that the use of HES in thermally injured and septic individuals has no deleterious effects on RES function, nor does it accumulate in the lungs, and hence, should be advocated for use in these situations.