The influence of fibronectin administration on the incidence of sepsis and septic mortality in severely injured patients. The Medical College of Georgia Fibronectin Research Group.

Eighty-five trauma patients between the ages of 18 and 55, with American College of Surgeon's (ACOS) trauma scores greater than or equal to 7 were entered into a double-blind, randomized, placebo-controlled study to assess the efficacy of prophylactic fibronectin (Fn) administration on clinical course, sepsis development, and septic mortality. Patients were randomized on admission to receive purified human virus-inactivated Fn or placebo control (human serum albumin, HSA). Fn or HSA was administered on a daily basis if and when the patient was Fn deficient (less than 75% normal). When a Fn deficiency was not evident, the patient received saline. Seventy one patients developed Fn deficiencies during their initial clinical course: 36 received Fn, 35 received HSA. Fourteen patients did not develop a Fn deficiency after trauma and thus received only saline. Analysis of admission data demonstrated no significant differences between the three groups with respect to extent of injury (injury severity score, ACOS trauma score) or physiologic assessments of organ function (serum creatinine, bilirubin, lactic acid). On day 1 after trauma, Fn levels were shown to correlate with other plasma proteins and cellular components (range of r values, 0.24 to 0.75; all p less than 0.05), but not with organ function parameters. Eighteen of 85 patients became septic as judged by clinical criteria. Ten of these patients had received Fn (10 of 36), five had received HSA (5 of 35), and three had received only saline (3 of 14) before the development of sepsis (differences not significant). When septic, nine of 17 patients developed Fn deficiencies. Six patients received Fn while septic, three received albumin, and eight received saline. Seven patients died: 5 of 6 Fn patients, 1 saline, and 1 HSA recipient. Our data suggest that exogenous Fn repletion in states of deficiency does not alter clinical course, the development of sepsis, or septic mortality.

A competitive inhibition assay for gelatin binding fibronectin.

A competitive inhibition assay for functional fibronectin (Fn), based on ELISA technology, is described. The assay measures Fn's physiologic ability to bind to denatured collagen (gelatin). Affinity-purified Fn inhibits the binding of alkaline phosphatase coupled Fn to gelatin-coated wells of a microtiter plate in a concentration-dependent manner. The assay range is 50-500 micrograms Fn/ml, which is suitable for the measurement of plasma Fn in both normal and opsonin deficient individuals. It is reproducible over an eightfold dilution of plasma and is resistant to interference by normal plasma proteins. The assay described is quick, quantitative, and reproducible, and satisfies the need for a measure of functional Fn activity in the clinical laboratory.

Sequestration of fibronectin at the site of an injury.

Fibronectin (Fn), a normal serum protein which appears to have important roles in wound healing and in reticuloendothelial system function, is depressed by most types of trauma. Fn is released into the tissue at the site of an injury which suggests the depression is the result of Fn sequestration at the wound site. A competitive inhibition assay for Fn was used to measure the concentration of Fn in fluid draining the site of a radical mastectomy and the level in concurrently obtained plasma. Plasma levels of Fn were significantly depressed following surgery but were returning toward normal by 24 hours postsurgery. The concentration of Fn in drainage fluid collected two hours postop was slightly but significantly lower than the plasma collected simultaneously. By 8 hours after surgery, drainage fluid levels were significantly higher than that in concurrently obtained plasma, and the difference was even more pronounced at 24 hours postop. Fn in the drainage fluid retained opsonic activity but at a lower level than the opsonic activity in plasma. The higher concentration of Fn in drainage fluid than in plasma appears to be due to binding of the Fn to tissue debris in the exudate, which prevents the reentry of Fn into the vascular compartment.

Shock and resuscitation. III. Accurate refractometric COP determinations in hypovolemia treated with HALFD.

In 38 critically burned patients with symptomatic hypovolemia being treated by intravenous fluids, the accuracy of colloid oncotic pressure (COP) calculated from the refractometrically-determined serum total protein (TPRI) was compared with COP values determined by a commercially-available clinical oncometer. Sera were obtained randomly from seven patients receiving Ringer's lactate solution, five receiving a hypertonic solution (240 mOsm Na+) and 26 receiving a hypertonic solution containing albumin (12.5 gm/liter, HALFD method). There was poor correlation between COP measure and that calculated from RI in patients receiving colloid-free fluid, but high correlation (r = 0.925) in patients receiving HALFD. There was high correlation (r = 0.951) between measured COP and values calculated from TPRI in patients receiving hypertonic fluid, colloid containing hypertonic fluid, or no fluid:COP = 4.08 (TPRI)--4.61.

Studies in burns, XVI: The effect of surgical trauma on metabolic heat production.

As part of an ongoing study of the naturally-occurring skin lipid ethyl linoleate as an adjunct for reducing post-burn hypermetabolism and hyperevaporation, we have conducted a series of evaluations of metabolic heat production (M) using a clinical partitional calorimeter. In this article, we describe the metabolic chamber and its use in evaluating the change in M in pre- and postoperative patients. We determined that dry heat losses (radiation and convection) comprise the major components of heat loss in the "normal" and traumatized individual with intact skin. In the post-operative state, metabolic heat production increases significantly above the preoperative levels, the percentage of change being accurately described by a first order exponential equation. In the postoperative patient, possibly because of a physiologic shift in source of metabolic substrate, stored heat increases significantly. These data may be useful in allowing approximate correction of the metabolic heat equation when studying the burn patient where no "control" is attainable and where some approximation of the contribution of "pure" trauma must be made.

Studies in shock and resuscitation, I: use of a hypertonic, albumin-containing, fluid demand regimen (HALFD) in resuscitation.

We have reevaluated and clinically tested the current concepts of shock and resuscitation on a logical, physiological, and physical basis. We have considered the currently accepted resuscitation paradigm which is based upon the thesis that early rapid resuscitation of "lost" fluid volume is mandatory and that adequacy of resuscitation can be evaluated by central venous pressure, PAP, PAWP, pulse rate, blood pressure, and/or urine volume. Such methods also accept as natural concomitants that capillary beds are "damaged by injury"; that they "leak" salt, fluid, and albumin; and that these are expected occurrences which are injury-related. We have also examined and clinically evaluated the thesis that MAP is a primary reflector of the relationships between volume and the size of the currently available functional vascular space. (Currently available functional vascular space is mediated through the baroreceptor (stretch receptor)/neuroendocrine mechanisms.) Under this hypothesis, fluid resuscitation comprises infusion of a volume per unit time given so as to replete currently measurable fluid losses and to normalize and/or sustain MAP and the normal osmolar and oncotic relationships at the capillary/tissue interface while holding hydrostatic pressure at normal. Using burn injury as a model, we compared statistically homogeneous, randomly selected groups of burn patients who were resuscitated using a hypotonic fluid (130 mOsm/liter) alone (group R: 7 patients), hypertonic fluid (240 mOsm/liter) alone group H: 5 patients), or the hypertonic fluid containing albumin (12.5 g/liter) (group A: 7 patients). The results indicate that significantly smaller volumes of fluid were needed to resuscitate the patients in group A with a significantly more rapid normalization of physical, physiological, and biochemical parameters. We conclude that the physically and physiologically appropriate method of resuscitation, demonstrated in burn injury, comprises the use of a fluid given at a rate: (1) to maintain mean arterial and hydrostatic pressures within normal range; (2) that delivers a volume per unit time which does not exceed the capacity of the currently available functional vascular space; (3) that replaces concurrent measurable fluid losses; (4) that is hypertonic (to normalize capillary/tissue osmotic gradients); and (5) that contains colloid (to normalize capillary/tissue osmotic gradients); and (5) that contains colloid (to normalize capillary/tissue oncotic gradients). We further conclude that salt, fluid, and colloid loss into the interstitium during resuscitation frequently is due to the rate delivered and/or the physical nature of the fluid used and not to capillary bed damage outside the zone of injury.

Shock and resuscitation. II: Volume repletion with minimal edema using the "HALFD"(Hypertonic Albuminated Fluid Demand) regimen.

A hypertonic albuminated fluid demand regimen (HALFD) for resuscitation has been used in burn patients since January 1, 1976. The effects of the HALFD method were compared with hypertonic fluid and Ringer's lactate resuscitation. Specific attention was directed to fluid, colloid, and volume changes. Resuscitation was guided by maintaining the mean arterial pressure between 60 to 110 torr, and urine volume at 30 to 50 ml/hr. Patients treated with the HALFD method fared significantly better clinically, needed less fluid, had less weight gain and plasma leak, and experienced slower plasma volume repletion than those treated more traditionally. We conclude that the HALFD method is a physically and physiologically appropriate paradigm for resuscitating the volume-depleted patient.

Studies in burns: XIV, Heling in burn wounds treated with Ethyl Linoleate alone or in combination with selected topical antibacterial agents.

Studies of the efficacy, in terms of burned wound healing, of a mixture of Ethyl Linoleate (ethyl 9-12 (cis, cis) octadecadienoate) with alpha-1-histidine, alpha-tocopherol, and TBHQ (hELate) was undertaken in 12 swine. The species was selected so as to study an animal with skin anatomy similar to the human. Statistically significantly greater healing occurred in 730 C/7sec contact burns (20% BSA) treated with hELate than in untreated burns in pigs. Further, there was no contracture noted in the hELate treated lesions, while marked contracture occurred in the untreated burns. Additionally, we noted that there was a proportional increase in weight gain amongst swine studied as their burn lesions epithelialized. In order to evaluate the compatibility of hELate with selected, currently-used topical antibacterial agents, 154 rabbits with 20% 730 C/7 sec contact burns were studied. The lipid was applied (0.01 ml/cm2 burn) at 1 hour postburning; the topical agent was applied at 2 hours post-burn and every 24-hours. All animals were washed once daily. hELate was applied only once. We found no statistical difference in the number of subjects healed or in the mortality between animals treated with hELate alone and those treated with the agent plus Gentamycin cream, Neosporin cream, and silver sulfadiazine 1% in Unibase USP (compounded at Medical College of Georgia specifically and only for this study.) We suggest that Ethyl Linoleate agent (hELate) may be used safely in combination with selected antibacterial substances. Further, these selected combinations seem to be non-toxic and appear to allow the calorie-saving and healing effects of the lipid to proceed unimpeded.