Takayoshi Matsuda

Herpes simplex virus and cytomegalovirus infections in burned patients.

Herpesvirus infections are commonly seen in immunosuppressed patients and may account for considerable morbidity and some mortality. We prospectively studied 52 patients with severe burn injuries in order to determine the prevalence of viral infections in this group of patients. Serologic testing was done each week to diagnose primary and reactivation infections. Twenty-seven of 52 patients (52%) became infected with either herpes simplex virus (HSV) or cytomegalovirus (CMV) or both. HSV infection was associated with older age, tracheal intubation, facial burn, inhalation injury, length of hospitalization, and the presence of full-thickness burn. CMV infection was associated with duration of hospitalization and full-thickness burn. Transfusion of blood products was not correlated with an increased incidence of primary or reactivation CMV infections. There was a significant correlation between the presence of these viral infections and bacterial sepsis (p less than 0.05). There was no significant association of HSV or CMV infections with mortality.

Dispase/detergent treated dermal matrix as a dermal substitute

A method for preparing acellular allogeneic dermal matrix (ADM) and its effectiveness as a dermal substitute are described. Treatment of rat skin with Dispase followed by Triton X-100 completely removed cellular components from the dermis. Subcutaneously implanted ADM evoked no immunological reaction and 20 weeks after implantation, the size of the implanted ADM was reduced to about 60 per cent of its original area. ADM became completely vascularized within 2 weeks after implantation into full thickness skin defects in the rat and inhibited extensive wound contracture. A second layer of ADM placed onto the implanted ADM served as an excellent dressing, providing mechanical protection and permitting vascularization of the underlying implant. Onlay skin autografts placed onto vascularized allogeneic ADM showed good survival when the skin was grafted more than 1 week after ADM implantation. Dispase/detergent treated ADM derived from animal or human skin may be useful in full thickness skin defects providing a vascularized bed for subsequent epidermal coverage.

Reduced fluid volume requirement for resuscitation of third-degree burns with high-dose vitamin C

The effects of high-dose vitamin C therapy (170 mg, 340 mg, and 680 mg/kg/day) were evaluated in 70% body surface area third-degree burns in guinea pigs that were resuscitated with 1 ml/kg/%burn Ringers lactate solution. The water content measurements of the burned skin at 24 hours after burn injury in the vitamin C-treated groups were significantly lower than those of the control group (1 ml/kg/%burn) and those of the standard resuscitation group (4 ml/kg/%burn). The cardiac outputs in the group that received 340 mg vitamin C were significantly higher than those of the control group but not significantly different than those of the standard therapy group at 2 hours after burn injury and thereafter. In comparison with the regimen of 340 mg vitamin C, the regimen of 680 mg vitamin C was no more beneficial, and the regimen of 170 mg was less effective. With administration of adjuvant high-dose vitamin C, we were able to reduce the total 24-hour resuscitation volume from 4 ml/kg/%burn to 1 ml/kg/%burn, while a comparable cardiac output was maintained.

The effects of high-dose vitamin C therapy on postburn lipid peroxidation

The effects of vitamin C treatment (14 mg/kg/hr) on postburn lipid peroxidation were evaluated in 12 dogs. A lymph duct above the ankle was cannulated bilaterally. Hourly lymph flow rates, plasma and lymph total protein concentrations, and plasma and lymph malondialdehyde concentrations were measured before the burn injury and for 24 hours after the burn injury. Four groups were employed: nonburn without treatment, nonburn with vitamin C treatment, burn without treatment, and burn with vitamin C treatment. The nonburn groups showed no significant differences in lymph flow rates, total protein flux, or lymph malondialdehyde level. In the burn groups the postburn hourly lymph flow rate increased by 850% without treatment and by 500% with vitamin C treatment, whereas the postburn hourly total protein flux increased by fiftyfold and twentyfold, respectively. There was a significant reduction in the postburn lymph malondialdehyde level in the group treated with vitamin C as compared with the nontreatment group. We conclude that high-dose vitamin C administration diminishes early postburn lipid peroxidation and reduces microvascular leakage of fluid and protein.

Characterization of acellular dermal matrices (ADMs) prepared by two different methods

The efficacy of acellular dermal matrix (ADM) in the treatment of full-thickness skin injuries as a dermal substitute depends on its low antigenicity, capacity for rapid vascularization, and stability as a dermal template. These properties will be determined largely by the final composition of the ADM. We have treated human skin with either Dispase followed by Triton X-100 detergent or NaCl followed by SDS detergent, cryosectioned the resulting ADMs, and then characterized them immunohistochemically. Staining for cell-associated antigens (HLA-ABC, HLA-DR, vimentin, desmin, talin), extracellular matrix components (chondroitin sulfate, fibronectin, laminin, vitronectin, hyaluronic acid), elastin, and collagen type VII was dramatically reduced or absent from ADMs prepared by both methods. However, significant amounts of elastin, keratan sulfate, laminin, and collagen types III and IV were still observed in both ADMs. Both methods of ADM preparation resulted in extensive extraction of both cellular and extracellular components of the skin but retention of the basic dermal architecture. In general, ADM prepared by the NaCl-SDS method retained larger amounts of each antigen than did that prepared by the Dispase-Triton method. This was most evident for laminin and type VII collagen but larger amounts of type IV collagen, fibronectin, desmin, elastin, and HLA-DR were also evident in the NaCl-SDS ADM.

High-dose vitamin C therapy for extensive deep dermal burns

We studied the haemodynamic effects of antioxidant therapy with high-dose vitamin C administration (170 mg/kg/24 h) in guinea-pigs with 70 per cent body surface area deep dermal burns. The animals were divided into three groups of six animals each. Group 1 was resuscitated with Ringers lactate solution according to the Parkland formula; group 2 with 25 per cent of the Parkland formula with vitamin C; and group 3 with 25 per cent of the Parkland formula without vitamin C. There were no significant differences in heart rates or in blood pressures between the groups throughout the 24-h study period. Group 3 showed significantly higher haematocrit values at 3 h postburn and thereafter as compared with those of group 2. The cardiac output values of group 2 were significantly higher than those of group 3, but equivalent to those of group 1. The water content of the burned skin in group 2 was significantly lower than that in the other groups, indicating that increased postburn capillary permeability was minimized by the administration of vitamin C. With adjuvant high-dose vitamin C administration, we were able to reduce the 24-h resuscitation fluid volume from 4 ml/kg/per cent burn to 1 ml/kg/per cent burn, while maintaining adequate cardiac output.

Vitamin C reduces ischemia-reperfusion injury in a rat epigastric island skin flap model

Free radicals have been implicated in the cause of ischemia-reperfusion injury. Various agents have been used in an attempt to reduce ischemia-reperfusion injury pharmacologically, including free radical scavengers. Vitamin C (ascorbic acid), a well-known free radical scavenger, has not, to the best of our knowledge, been evaluated in this respect. Previous work at our institution has shown that vitamin C decreases capillary permeability, thus significantly reducing fluid resuscitation requirements in postburn cases. Because this is due in part to the scavenging effect of vitamin C on free radicals, we investigated the role, if any, of vitamin C on ischemia-reperfusion injury in a rat epigastric island skin flap model. Twenty-four adult Sprague-Dawley rats were divided into control and vitamin C groups. Superficial epigastric island skin flaps measuring 6.0 × 3.5 cm were raised. Pedicles were isolated and occluded with microvascular clamps for 6 hours. The flaps were then sutured back to their beds over Steri-Drape barriers. Fifteen minutes before reperfusion, the control group flaps were perfused via femoral artery cannulation with normal saline (2.5 ml/kg). The vitamin C–treated group was perfused in a similar fashion with 2.5 ml/kg of a vitamin C/normal saline solution (27 mg/ml). The animals were observed for 7 days, and the percentage of flap survival was determined using a paper template technique. The vitamin C–treated group demonstrated a significantly higher percentage of flap survival than did the control group (25.8% mean vs. 7.5% mean, p < 0.025). In this animal model, vitamin C reduced or limited reperfusion injury after 6 hours of ischemia. Its presumed mechanisms of free radical reduction and its relative safety make vitamin C a promising area of investigation in future animal studies as well as in human studies examining reperfusion injury.

Effects of high-dose vitamin C administration on postburn microvascular fluid and protein flux.

The effects of vitamin C treatment (14 mg/kg/hr) on burn injury were evaluated in the hind paws of 12 mongrel dogs. A lymph duct above one hind paw of each dog was cannulated. Hourly lymph flow rates (QL) and plasma and lymph total protein concentrations were measured before the burn injury and for 6 hours after the burn injury. Data from 24 paws were divided into four groups: nonburn without treatment, nonburn with treatment, burn without treatment, and burn with treatment. The nonburn groups showed no significant differences in QL or in total protein flux. In the burn groups the postburn hourly QL increased by sevenfold in the nontreatment group and only by threefold in the treatment group, whereas the postburn hourly total protein flux increased by fifteenfold and fivefold, respectively. We conclude that administration of high-dose vitamin C reduces early postburn microvascular leakage of fluid and protein.

Acute electrical burns: a 10-year clinical experience.

We have reviewed 113 cases of electrical burns treated at the Cook County Hospital Burn Center during the past 10 years. There were 3265 acute burn admissions during this period. the incidence of electrical burns being 3.5 per cent. Low-voltage electrical burns occurred in 82 of the 113 patients (73 per cent). These were caused mostly by household electricity supplies, occurred in children, and were preventable. Arc burns of the perioral region were allowed to heal spontaneously. The surgical management of other arc burns and flash burns was similar to that for most deep burn wounds. The incidence of high-voltage electrical injuries was 27 per cent in our series. Over 50 per cent of these injuries were not work-related. These tended to occur outside the home in young adult males and were also frequently preventable. None of these patients developed acute renal failure. Early surgical debridement of devitalized tissue with allografting, followed by delayed definitive wound closure or amputation prevented septic complications. Early fasciotomy appeared to have little effect on complete limb salvage. Limb loss continues to be the major factor contributing to the high morbidity associated with these injuries. All 113 patients survived. We attribute this to early transfer of patients to our Burn Unit, aggressive fluid resuscitation, continuous haemodynamic and metabolic support, and early surgical intervention.

The effect of burn wound size on ureagenesis and nitrogen balance.

Hypermetabolic burn patients are frequently in negative nitrogen balance despite provision of estimated caloric needs. We studied 18 thermally injured adult patients in order to evaluate the relationship of burn wound size to urea production and nitrogen balance. We selected data from 147 patient-days when the patients received 100 +/- 25% of their estimated caloric needs. Three significantly different burn size groups (by body surface area [BSA]) were identified by calculation of the catabolic index (CI): group 1, 0-10% BSA (CI = -0.1); group 2, 11-30% BSA (CI = 6.4); and group 3,31-60% BSA (CI = 10.5). The urine urea nitrogen (UUN) for groups 1,2, and 3 was 11.1, 18.9, and 25.3 gm/day, and nitrogen balance was 1.0, -3.9, and -5.8 gm/day, respectively. When nitrogen was given in a calorie:nitrogen ratio of 150:1, only those patients in group I were able to achieve positive balance. We conclude that large burn wounds are associated with increased ureagenesis and impaired nitrogen retention. The protein intake, at the customary calorie:nitrogen ratio of 150:1, may not provide adequate nitrogen to achieve equilibrium, even when energy demands have been met, in patients with burn wounds greater than 10% BSA.