Neutrophil intracellular kill following thermal injury. Different bactericidal capability for patients' organisms and laboratory organisms.

Sixteen patients with septic complications of severe thermal injury were studied with respect to neutrophil intracellular-killing power against clinical isolates from the patients themselves and against other laboratory organisms. Simultaneous measurements of neutrophil chemotaxis, helper/suppressor lymphocyte ratios, and serum IgG concentrations were also carried out. Neutrophils from patients who survived had diminished intracellular-killing capacity for their own organisms, but normal capacity for killing laboratory organisms either matched or unmatched with the patients' own isolate's species. In these patients, the chemotactic index, the lymphocyte helper/suppressor ratio, and the serum IgG concentration remained within normal limits. Neutrophils from patients who died failed to kill their own, as well as laboratory, organisms. In these patients, the chemotactic index, lymphocyte helper/suppressor ratio, and IgG concentration were significantly diminished. The biological implications of these findings are noted.

Effect of immunoglobulin G therapy on serum antibody titers to cytomegalovirus in burn patients.

We attempted to determine the incidence and significance of cytomegalovirus infection and the effect of immunoglobulin G infusions on specific cytomegalovirus titers in burn patients. On admission, 48 percent of a group of 120 patients (mean burn size 28.5 percent of the total body surface area) were seronegative, including 95 percent of all patients under 20 years of age. Subsequently, 4 of a subgroup of 26 patients (15 percent) had development of a primary infection, and 1 of these patients died from overwhelming bacterial infection. Immunoglobulin G infusion used in the prophylaxis of the septic complications achieved high titers of cytomegalovirus-specific immunoglobulin G, as well as the subsets immunoglobulin G1 and immunoglobulin G3 which are also active against cytomegalovirus.

A new algorithm for calculation of blood loss in excisional burn surgery.

One hundred and two patients who sustained thermal injury and who underwent 155 excisional procedures were prospectively studied in order to determine an accurate blood loss formula. Blood loss (mean +/- S.D.) is expressed as the percentage of the total blood volume lost for each per cent of body surface area excised and autografted. There was no significant difference between the blood loss for the overall group of procedures (4.1 +/- 0.24) and the various subgroups indicating that the outcome was not influenced by the method, extent or timing of excision or by the use of tourniquets. From the authors' calculations, approximately 196 ml of blood is required for each per cent of body surface area excised and autografted.

Autoantibody formation in burn patients after inhibition of suppressor T cell activity with polymyxin B.

After thermal injury, treatment with polymyxin B blocks suppressor T cell activity by uncoupling endotoxin-mediated T cell activation, but the effect on autoantibody formation is unknown. We examined the presence of antinuclear antibodies to native DNA; to soluble antigens Ro/SSA, La/SSB, Sm, nRNP; and to antiepithelial antibodies in 12 burn patients before and after treatment with polymyxin B and in 24 samples from control burn patients. Low titer antinuclear antibody activity was detected in 25% of pretreatment and 78% of posttreatment samples (p less than 0.01) and in 16.7% of control patients. One polymyxin B-treated patient had a significant antinuclear antibody titer both before and after treatment. Antiepithelial antibodies were detected in 16.7% of early polymyxin B-treated samples and 11.1% of late samples (p less than 0.05) but were also present in 20.8% of controls. Antibodies to native DNA, Ro/SSA, La/SSB, Sm, and nRNP were not detected in any sera.

Laser Doppler flowmetry evaluation of burn wound depth.

Hypothesizing that reduced blood flow to various levels in thermally damaged dermis is related to the depth of burn, we studied 59 burns in 41 patients, with an age range of 18 months to 67 years, with improved laser Doppler blood flow technology to determine burn depth on admission. Two hundred and sixty-eight laser Doppler measurements were made in 59 burn wounds in 41 patients. Of the 129 burn wounds with laser Doppler readings of less than 1.4 on admission, 127 were classified ultimately through clinical observation as either deep second- or third-degree burns and required excision and closure. Therefore predictive value of a positive result (i.e., laser Doppler value less than 1.4) on admission was 98.4% using laser Doppler measurements. Clinical estimation did not correlate as well with the depth of injury.

Anaphylotoxin levels following thermal injury.

Following thermal injury, anaphylotoxins (C3a and C5a) are generated by complement activity. We measured C3a and C5a levels serially in 18 seriously burned patients (mean burn size = 37.9 per cent body surface area) over the initial 3 weeks following injury. Values for C3a were significantly increased when compared with normal controls, with maximum levels during the second week, while C5a levels were slightly elevated initially. These levels did not correlate with the extent of tissue injury, the development of septic complications or the clinical outcome. However, it appears likely that C3a and C5a may be responsible for some of the pathophysiological alterations observed following thermal injury.