Biomedical subjects

C W Goodwin

Publications and source records attributed to C W Goodwin.

At least 19 recordsLinked to original sources

PubMed2001

Distant pedicle flaps for soft tissue coverage of severely burned hands: an old idea revisited.

Burns to the hand that are complicated by exposure of bone, joint or tendon cannot be closed with conventional skin grafts and require flap procedures to prevent further damage. Local or regional flaps may be unavailable if electrical or blast trauma produces a large zone of injury, or when forearm burn injury extends beyond fascia. Free tissue transfer may not be tolerated by critically ill burn patients. In these circumstances, distant pedicle flaps are one option for safe and effective soft tissue coverage. Over a 5-year period, we have performed six distal pedicle flaps for coverage of exposed hand structures when local or free flaps were contraindicated or unavailable. The patients required an average of 4.5 surgical procedures to complete hand reconstruction and soft tissue coverage. Soft tissue coverage was completely successful in five patients and partially successful in one patient. Single stage local or free flaps remain the treatment of choice when burned hands cannot be covered with skin grafts. When these flap options are not available, distant pedicle flaps provide a safe alternative.

Adolescent↗

PubMed2001

Thermally injured patients are at significant risk for thromboembolic complications.

BACKGROUND: The incidence of thromboembolic complications such as deep vein thrombosis (DVT) and pulmonary embolism (PE) in thermally injured patients is considered sufficiently uncommon that routine prophylactic measures are not warranted. Nevertheless, the incidence of DVT/PE may be increasing. METHODS: The records of 1,300 patients admitted to our unit from January 1990 to June 1995 were reviewed. RESULTS: Twenty-three patients developed a clinically significant DVT, eight patients developed a PE, and two patients developed both a DVT and a PE, for an overall DVT/PE incidence of 2.9%. Four of 10 PEs were felt to be fatal. The DVT/PE patients were older (mean age, 42.6 vs. 28.7; p < 0.001) and had larger burns (37% vs. 18%, p < 0.001) than patients without evidence of DVT/PE. Body weight appeared to also influence DVT/PE rates, with obese patients (>30% over ideal body weight) having a higher incidence than patients with low or normal body weight (7.2 vs. 2.7%, p < 0.015). Age and total body surface area (TBSA) burn had a synergistic effect on DVT/PE risk, with the sum of age and TBSA burn exerting the strongest independent effect when discriminant function analysis was performed (p < 0.001). CONCLUSION: One can identify a population at increased risk of DVT/PE on the basis of the sum of age and TBSA burn, but prospective screening trials that assess all risk factors for DVT/PE should be performed before routine prophylaxis is used in thermally injured patients.

Adult↗

PubMed2001

Delayed partial liquid ventilation shows no efficacy in the treatment of smoke inhalation injury in swine.

In an earlier neonatal porcine model of smoke inhalation injury (SII), immediate postinjury application of partial liquid ventilation (PLV) had dramatic beneficial effects on lung compliance, oxygenation, and survival over a 24-h period. To explore the efficacy of PLV following SII, we treated animals at 2 and 6 h after SII and followed them for 72 h. Pigs weighing 8-12 kg were sedated and pharmacologically paralyzed, given a SII, and placed on volume-cycled, pressure-limited ventilation. Animals were randomized to three groups: group I (+SII, no PLV, n = 8), group II (+SII, PLV at 2 h, n = 6), and group III (+SII, PLV at 6 h, n = 7). Ventilatory parameters and arterial blood gasses were obtained at scheduled intervals. The PLV animals (groups II and III) followed a worse course than group I (no PLV); PLV groups had higher peak and mean airway pressures, oxygenation index, and rate-pressure product (a barotrauma index) and lower lung compliance and arterial partial pressure of oxygen-to-inspired oxygen fraction ratio (all P < 0.05). PLV conferred no survival advantage. The reported beneficial effects of PLV with other models of acute lung injury do not appear to extend to the treatment of SII when PLV is instituted in a delayed manner. This study was not able to validate the previously reported beneficial effects of PLV in SII and actually found deleterious effects, perhaps reflecting the predominance of airway over alveolar disease in SII.

Animals↗

PubMed2000

Accelerated healing with a mesh autograft/allodermal composite skin graft treated with silver nylon dressings with and without direct current in rats.

PURPOSE: Evaluation of the healing and persistence of a meshed composite skin graft applied without immunosuppression. METHODS: The contraction of wounds grafted with 9:1 split-thickness autograft/1.5:1 allodermal mesh composite skin grafts (auto/allo MCSGs) was investigated. No immunosuppressive agent was applied. Male ACI rats and female Lewis rats reciprocally served as allodermis graft donors and recipients. Autograft/dermal autograft and allograft/dermal allograft MCSGs were the controls. RESULTS: AT 3 months after grafting, when epithelized auto/allo MCSG wounds were measured by computerized morphometric analysis, the silver nylon (SN) dressing group displayed less contraction than the Vaseline (petroleum jelly) dressing group (p < 0.003), and direct current treatment (SNDC) was more effective than SN (p < 0.005). The histologic structures of the hair follicles appear to confine the rejection process to the allogeneic follicles of the graft. The focal nature of the rejection process and the relatively low antigenicity of the dermal matrix allowed the survival of the allodermis layer. Although direct current significantly enhanced MCSG healing, SN and SNDC were not the immunosuppressive agents that were confirmed. CONCLUSION: This type of MCSG can heal without immunosuppressive treatment.

Animals↗

PubMed2000

Half-life of blood carboxyhemoglobin after short-term and long-term exposure to carbon monoxide.

BACKGROUND: In models of smoke inhalation injury and carbon monoxide poisoning blood carboxy-hemoglobin (COHb) levels decrease faster than predicted by the generally recognized half-life of COHb. We studied the effects of duration of exposure to carbon monoxide (CO) on the subsequent CO elimination. METHODS: Each of four sheep were insufflated with CO gas mixtures either for a few minutes (short-term exposure) or for several hours (long-term exposure), then ventilated with air for 3 hours. Serial COHb concentrations were analyzed by using a two-compartment, single central outlet mathematical model. RESULTS: Short-term exposures exhibited biphasic decreases of COHb concentration compatible with a two-compartment model; an initial rapid decrease (half-life 5.7 +/- 1.4 minutes) was followed by a slower phase (103 +/- 20.5 minutes). Long-term exposures exhibited almost monophasic decreases, which were nevertheless compatible with the model (half-life, 21.5 +/- 2.1 and 118 +/- 11.2 minutes). CONCLUSION: This study demonstrated different patterns of CO elimination curve, which suggests distribution of CO to two compartments having different rates of equilibration.

Administration, Inhalation↗

PubMed1999

Dermatologists and the burn center.

Severe cutaneous disease and injury often is best treated in the specialized treatment environment of a burn center. Skilled burn treatment personnel combine critical care expertise with extensive clinical experience in the management of severe cutaneous injury and disease. In addition to thermal injury, the burn center is the ideal environment for patients with progressive toxic epidermal necrolysis, pemphigoid lesions, and invasive cutaneous infection. Recent research indicates that the burn wound is a dynamic structure whose ultimate extent is modifiable by manipulations of the local anatomic and molecular environment. The many unanswered questions on the pathogenesis and treatment of both the "medical" and "surgical" cutaneous processes require close collaboration between the dermatologist and the burn team.

Burn Units↗

PubMed1999

Direct current reduces accumulation of Evans Blue albumin in full-thickness burns.

BACKGROUND: Application of direct current (DC) to a burn wound limits extension of the zone-of-stasis and reduces wound tissue edema. OBJECTIVE: To study the effects of DC on extravasation of plasma proteins after burn by using Evans blue (EB) as a marker of plasma albumin. MATERIALS AND METHODS: Male Sprague-Dawley rats with 20% total body surface area full-thickness scalds (100 degrees C/10 sec) were used as the experimental model. Burn wounds were treated with plain nylon, silver-nylon, silver-nylon and 40 microA DC, or no dressing. EB (30 mg/kg) was injected immediately or at variably delayed postburn (PB) times and accompanied by DC application at various time intervals PB. Tissue content of Evans blue was assessed at different times after injection of the dye or infliction of burn injury. RESULTS: Evans blue albumin (EBA) concentration in untreated burn wounds (307.7 microg/g tissue) was nine times greater than in unburned skin (36.5 microg/g tissue) at 48 hours PB. When animals received a DC and EB injection immediately PB, DC treatment reduced EBA concentration by 60% at any time point PB. When EB was injected immediately PB, or at variably delayed times PB, accompanied by DC immediately PB, or at variably delayed times PB, DC reduced EBA accumulation at all examined times PB by more the 50% (p < 0.001). CONCLUSION: EBA and edema fluid accumulation in burn wound change in concert after injury and show similar response to DC treatment.

Animals↗

PubMed1998

Observations on the risk of resistance with the extended use of vancomycin.

OBJECTIVE: To document the risk of the development of vancomycin-resistant bacteria in a population of seriously burned patients during a 10-year period of common vancomycin hydrochloride use. DESIGN: Retrospective study. SETTING: The US Army Institute of Surgical Research, Burn Center, Fort Sam Houston, Tex. POPULATION AND METHODS: Microbiology, infection, and antibiotic use records collected during the hospitalization of 2266 consecutively admitted seriously burned patients were reviewed. Vancomycin was the primary therapeutic agent used for gram-positive infections and was also used as a perioperative prophylactic antibiotic during burn wound excision. This policy was established prior to this review because of a high incidence of methicillin-resistant Staphylococcus aureus colonization and an anecdotal association of increased beta-lactam resistance in endemic gram-negative pathogens associated with the use of penicillinase-resistant penicillins and cephalosporins. MAIN OUTCOME MEASURES: Isolation of vancomycin-resistant enterococci (VRE) or other gram-positive organisms resistant to vancomycin. RESULTS: Examinations of 15 125 gram-positive isolates, including 957 enterococci, for in vitro sensitivity to vancomycin yielded 3 VRE isolates in 3 patients. Vancomycin was used prior to VRE isolation in one of these patients. Resistance was found in 3 other organisms (2 Corynebacterium species, 1 Lactobacillus species). Vancomycin was used prior to these isolations in 2 of 3 patients. None of the vancomycin-resistant organisms was associated with infection and all 6 patients survived. Vancomycin-resistant enterococci or other vancomycin-resistant gram-positive organisms were not found in 663 patients treated with vancomycin for documented gram-positive infections or in 1027 patients where perioperative vancomycin was used. CONCLUSION: Use of vancomycin as the primary therapeutic agent in seriously burned patients was not associated with increased risk of VRE isolation or VRE infection.

Adult↗

PubMed1998

Burn wound infections: current status.

The burn wound represents a susceptible site for opportunistic colonization by organisms of endogenous and exogenous origin. Patient factors such as age, extent of injury, and depth of burn in combination with microbial factors such as type and number of organisms, enzyme and toxin production, and motility determine the likelihood of invasive burn wound infection. Burn wound infections can be classified on the basis of the causative organism, the depth of invasion, and the tissue response. Diagnostic procedures and therapy must be based on an understanding of the pathophysiology of the burn wound and the pathogenesis of the various forms of burn wound infection. The time-related changes in the predominant flora of the burn wound from gram-positive to gram-negative recapitulate the history of burn wound infection. Proper clinical and culture surveillance of the burn wound permits early diagnosis of gram-positive cellulitis, and the stable susceptibility of beta-hemolytic streptococci to penicillin has eliminated the threat of this once common burn wound pathogen. Selection and dissemination of intrinsic and acquired resistance mechanisms increase the probability of burn wound colonization by resistant species such as Pseudomonas aeruginosa. Even so, effective topical antimicrobial chemotherapy and early burn wound excision have significantly reduced the overall occurrence of invasive burn wound infections. Individual patients, usually those with extensive burns in whom wound closure is difficult to achieve, may still develop a variety of bacterial and nonbacterial burn wound infections. Consequently, the entirety of the burn wound must be examined on a daily basis by the attending surgeon. Any change in wound appearance, with or without associated clinical changes, should be evaluated by biopsy. Quantitative cultures of the biopsy sample may identify predominant organisms but are not useful for making the diagnosis of invasive burn wound infection. Histologic examination of the biopsy specimen, which permits staging the invasive process, is the only reliable means of differentiating wound colonization from invasive infection. Identification of the histologic changes characteristic of bacterial, fungal, and viral infections facilitates the selection of appropriate therapy. A diagnosis of invasive burn wound infection necessitates change of both local and systemic therapy and, in the case of bacterial and fungal infections, prompt surgical removal of the infected tissue. Even after the wounds of extensively burned patients have healed or been grafted, burn wound impetigo, commonly caused by Staphylococcus aureus, may occur in the form of multifocal, small superficial abscesses that require surgical debridement. Current techniques of burn wound care have significantly reduced the incidence of invasive burn wound infection, altered the organisms causing the infections that do occur, increased the interval between injury and the onset of infection, reduced the mortality associated with infection, decreased the overall incidence of infection in burn patients, and increased burn patient survival.

Adolescent↗

PubMed1998

Apoptosis and accidental cell death in cultured human keratinocytes after thermal injury.

The respective roles of apoptosis and accidental cell death after thermal injury were evaluated in normal human epidermal keratinocytes. By coupling the LIVE/DEAD fluorescence viability assay with the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method and ultrastructural morphology, these two processes could be distinguished. Cells were grown on glass coverslips with a microgrid pattern so that the results of several staining procedures performed sequentially could be visualized in the same cells after heating at temperatures of up to 72 degrees C for 1 second. After exposure to temperatures of 58 to 59 degrees C, cells died predominantly by apoptosis; viable cells became TUNEL positive, indicating degradation of DNA. After exposure to temperatures of 60 to 66 degrees C, both TUNEL-positive viable cells and TUNEL-positive nonviable cells were observed, indicating that apoptosis and accidental cell death were occurring simultaneously. Cells died almost immediately after exposure to temperatures above 72 degrees C, presumably from heat fixation. The fluorescent mitochondrial probe MitoTracker Orange indicated that cells undergoing apoptosis became TUNEL positive before loss of mitochondrial function. Nucleosomal fragmentation of DNA analyzed by enzyme-linked immunosorbent assay and gel electrophoresis occurred after exposure to temperatures of 58 to 59 degrees C. The characteristic morphological findings of cells undergoing apoptosis, by transmission electron microscopy, included cellular shrinkage, cytoplasmic budding, and relatively intact mitochondria. Depending on temperature and time of exposure, normal human epidermal keratinocytes may die by apoptosis, accidental cell death, or heat fixation.

Apoptosis↗

PubMed1998

Preventable burns associated with the misuse of gasoline.

Gasoline is intended for use as a motor fuel, but the universal availability of gasoline in the home encourages misuse as a solvent, insecticide, accelerant or cleaning solution. The careless or inappropriate use of gasoline may result in burn injury. We examined the circumstance of gasoline-related injury in a population admitted to one burn centre to determine the potential for burn prevention efforts. A retrospective review of all burn admissions to one centre for the years 1978 to 1996 demonstrated hat 1011 of 4339 acute admissions (23.3%) were gasoline-related. This group had an average total burn size of 29.8% total body surface (TBSA) and an average full thickness injury of 14.4% TBSA. There were 144 fatalities resulting from gasoline-associated burn injury. Where such determination could be made, the use of gasoline was judged to be inappropriate or unsafe in 687 of 788 cases (87.1%). Ninety of 144 fatalities (62.5%) were associated with inappropriate or unsafe use of gasoline. The careless or inappropriate use of gasoline poses significant risk of burn injury. The indoor use of gasoline, as well as use of gasoline for purposes other than as a motor fuel, should be strongly discouraged.

Accidents, Home↗

PubMed1998

Body habitus as a predictor of burn risk in children: do fat boys still get burned?

Previous research at this institute has demonstrated that heavy-for-age boys are more burn prone than their normal sized counterparts. As this study is now 26 years old, we reexamined the anthropomorphic indices of 372 children admitted to one burn center between January 1991 and July 1997 to determine if this trend was still evident. Male children were over-represented in the < or =5th and >95th percentiles for both height (p < 0.001, p < 0.05) and weight (p < 0.01, p < 0.001). Female children were over-represented in the < or =5th and > 95th percentiles for height (p < 0.01, p < 0.05). Twenty-eight percent of boys at or below the 5th percentile for weight were burned as a result of known or suspected intentional injury, compared to 5.9% of the entire pediatric burn population. (p < 0.0004). 'Fat boys' continue to be over-represented in the pediatric burn population. Additionally, in the more recent time period, boys at or below the 5th percentile for height or weight and girls= < 5th percentile or >95th percentile for height are also over-represented. The increased frequency of burn injury in small-for-age children may reflect an increased risk of burn injury secondary to neglect or nonaccidental trauma.

Adolescent↗

PubMed1998

Fatal and near-fatal complications of liposuction.

Cosmetic liposuction is considered to be safe and effective in properly selected patients and is widely done as an outpatient or office procedure. When major complications occur, office-based practitioners may refer patients to a hospital emergency department, where medical personnel unfamiliar with this procedure may underestimate the risk of serious infection or other major complications. We present two cases of massive necrotizing fasciitis treated in a burn center after liposuction surgery. One patient died, and the second required lengthy hospitalization, extensive debridement, and split-thickness skin grafting of 22% of the total body surface area. Pain out of proportion to clinical findings is a hallmark of necrotizing fasciitis and should prompt consideration of this entity even in the absence of cutaneous signs of infection. Definitive diagnosis is made by biopsy and rapid section histologic analysis. Liposuction may result in major complications or death. Emergency department physicians or general surgeons may be called upon to manage such complications and should be aware of these risks.

Abdominal Muscles↗

PubMed1998

Inhaled nitric oxide prevents left ventricular impairment during endotoxemia.

We evaluated the effect of long-term inhalation of nitric oxide (NO) on cardiac contractility after endotoxemia by using the end-systolic elastance of the left ventricle (LV) as a load-independent contractility index. Chronic instrumentation in 12 pigs included implantation of two pairs of endocardial dimension transducers to measure LV volume and a micromanometer to measure LV pressure. One week later, the animals were divided into a control group (n = 6) or a NO group (n = 6). All animals received intravenous Escherichia coli endotoxin (10 micrograms. kg-1. h-1) and equivalent lactated Ringer solution. NO inhalation (20 parts/million) was begun 30 min after the initiation of endotoxemia and was continued for 24 h. In both groups, tachycardia, pulmonary hypertension, and systemic hyperdynamic changes were noted. The end-systolic elastance in the control group was significantly decreased beyond 7 h. NO inhalation maintained the end-systolic elastance at baseline levels and prevented its impairment. These findings indicate that NO exerts a protective effect on LV contractility in this model of endotoxemia.

Administration, Inhalation↗

PubMed1997

Effects of burns on inhalation injury.

BACKGROUND: There are few studies of smoke injury combined with thermal burn. METHODS: Seven sheep (G1) received smoke injury alone; eight (G2) received a 40% full-thickness scald burn immediately after smoke injury. All animals were resuscitated with lactated Ringer's solution and killed 48 hours after injury. Cardiopulmonary variables and blood gases were measured serially. Ventilation perfusion distribution was analyzed using the multiple inert gas elimination technique. Lung wet to dry weight ratio and malondialdehyde levels were determined. RESULTS: G2 resulted in early significant hemodynamic changes. Serum total protein concentration was significantly lower and malondialdehyde significantly higher in G2. However, PaO2, lung wet to dry weight ratio, and ventilation perfusion mismatching in G2 did not differ from those in G1. CONCLUSIONS: Although the addition of burn injury exaggerated the lung lipid peroxidation and hypoproteinemia in the presence of more pronounced hemodynamic changes, the pulmonary dysfunction was not accentuated.

Animals↗

PubMed1997

Optimized mesh expansion of composite skin grafts in rats treated with direct current.

BACKGROUND: The purpose of this study was to determine the optimum autoepidermal and allodermal expansion ratio of each component of a meshed composite skin graft (MCSG) that would lead to successful healing. METHODS: Male Sprague-Dawley rats were used as hosts of the MCSG and donors of autologous tissue. Male ACI rats were used as donors of allodermis. MCSGs with open meshed area (autoepidermal/allodermal) of 9:1/1.5:1, 9:1/3:1, 9:1/6:1, or 6:1/6:1 were applied to full-thickness skin defects and treated with a silver nylon dressing (SN) or SN with direct current (DC). Wound size, hair regrowth, and thickness of dermal layer were evaluated at 3 months. RESULTS: MCSGs of 9:1/1.5:1, 9:1/3:1, and 6:1/6:1 mesh ratios healed completely within 3 months with no difference in wound size between SN dressing groups or DC-treated groups. Application of DC reduced MCSG contraction and stimulated regrowth of hair. CONCLUSION: Fresh autoepidermis can be expanded 6:1 on a 6:1 allodermis or 9:1 on a 3:1 allodermis and achieve successful wound healing.

Animals↗

PubMed1997

Burn management. Initial assessment, management, and stabilization.

Burn statistics today reflect a downward trend in occurrence, and many burn injuries are preventable. The outcomes of the injury are greatly influenced by the care received at the scene of the accident and in the emergency department. Initial burn wound assessment and fluid resuscitation, as well as management of associated injuries, pain, and anxiety are critical elements of care and require monitoring by experienced burn team staff members.

Adolescent↗

PubMed1996

The effects of burn blister fluid on cultured keratinocytes.

OBJECTIVE: Previous studies have suggested that burn blister fluid (BBF) may be detrimental to the healing of the underlying wound bed. In this study, the effects of burn blister fluid on cultured keratinocyte proliferation and differentiation were examined and quantitated using various techniques. METHODS: At three different concentrations (2%, 10%, 20% in 20% fetal bovine serum/complete culture medium), 19 BBFs were tested in triplicate using 12 populations of cultured keratinocytes. All BBFs were collected from partial thickness burns within 72 hours of injury,. BBF was added on day 4 of the keratinocyte culture. The effect on proliferation and viability was assessed using trypan blue dye exclusion. Multiparameter flow cytometric analysis was used to quantitate population kinetics and cell size distribution. Keratinocyte differentiation was determined using immunohistochemical staining of differentiation markers and quantitation of cornified envelope formation. RESULTS: Relative to control fluid, the BBF caused a variable effect on proliferation, ranging from 67% inhibition to 103% stimulation with an overall 4% inhibition. The range of keratinocyte viability was narrower, with a similar overall 4% reduction. Using flow cytometry to analyze RNA/DNA content and cell size, the BBF caused a subtle shift in keratinocyte population kinetics and cell size distribution toward larger, less rapidly dividing cells. The BBF had no significant effect on expression of the differentiation markers, filaggrin and involucrin. Finally, the BBF did not alter terminal differentiation as it did not influence formation of cornified envelopes (BBF = 9.1 +/- 4.8%, control = 9.9 +/- 6.6%). CONCLUSION: Previous biochemical analysis has shown that BBF consists primarily of human serum filtrate with locally produced acute reactants. Our study suggests that BBF is biologically similar to serum and does not significantly alter keratinocyte proliferation or differentiation in vitro.

Adolescent↗