Biomedical subjects
A Luterman
Publications and source records attributed to A Luterman.
Artificial skin in the treatment of a large congenital nevus.
An 8 year-old girl had a large congenital nevus involving the posterior thigh, leg, and foot. The nevus on non-weight-bearing areas was resected, and the areas were resurfaced with artificial skin and ultra-thin split-thickness grafts. A good result was ultimately achieved. Our management of this case and the relative merits of this new technology are detailed.
Laser resurfacing complication.
A 43 year-old woman had full facial laser resurfacing for treatment of multiple actinic keratoses and aging skin. Healing was uneventful on most of the areas treated except the forehead, where a progressive nonhealing wound developed. After seeking numerous consultations around the Southeast, the patient came to our facility, 6 months after the initial laser treatment, with exuberant granulation tissue of the forehead and temples and a painful wound. Many topical treatments had been previously tried. Debridement and split-thickness skin grafting were done using general anesthesia. Pathologic analysis revealed hyperplastic granulation tissue and epidermal appendages. The wound healed with an improved aesthetic result. This case illustrates that seemingly impossible laser complications can be handled by a basic approach to wound healing.
An unusual mechanism of burn injury due to flaming drinks.
Bars and cocktail lounges serve various forms of flaming drinks, usually made with very high-proof alcohol. The drinks are lit and then served. If additional alcohol from the bottle is added to a still-burning drink, flames may spread up the stream of alcohol into the bottle and cause a flash of flame out the bottle's neck. Injuries can require grafting. Three cases are reported. A 32-year-old white female sustained burns covering 10 per cent of her body surface, including the face. Surgery with split-thickness grafts were required. Pressure garments were prescribed for 6 months. A 34-year-old black female was burned by a "volcano" drink. Burns covered 20 per cent of her body surface, including the face. Split-thickness grafts were required on multiple occasions. Infected wounds healed slowly. Reconstructive surgery has so far required eight procedures. A 39-year-old white male sustained severe burns to 10 per cent of his body, including the face. Grafting was carried out. Pressure garments were required. Permanent visible facial scarring is present in all three cases. This type of accident is readily preventable.
Prediction of trauma mortality using a neural network.
A neural network is a computerized construct consisting of input neurons (which process input data) connected to hidden neurons (to mathematically manipulate values they receive from all the input neurons) connected to output neurons (to output a prediction). Neural networks are created and trained via multiple iterations over data with known results. In 1993, 897 trauma patients were either declared dead in the emergency room (ER; 76 cases), admitted to the intensive care unit (427 cases, 36 deaths), or taken directly to the operating room (394 cases, 29 deaths). Using only data available from the ER, a neural network was created, and 628 cases were randomly selected for training. After 268 iterations, the network was trained to correctly predict death or survival in all 628 cases. This trained network was then tested on the other 269 cases without our providing the death or survival result. Its overall accuracy was 91 per cent (244 of 269 cases). It was able to predict correctly 60 per cent (12 of 20 cases) of the postoperative or post-intensive care unit admission deaths and 90 per cent (26 of 29 cases) of the deaths in the ER. Computerized neural networks can accurately predict a trauma patient's fate based on inital ER presentation. The theory and use of neural networks in predicting clinical outcome will be presented.
Injury severity score as a guide to nutritional management of the pediatric trauma patient.
Age, degree of injury, different metabolic rates, and growth complicate the estimation of nutritional requirements in the pediatric trauma victim. This study was designed to determine energy requirements of the injured child in relation to injury severity. Fourteen patients of 600 seen in a 5-year period met our criteria for evaluation with significant weight loss, caloric deficit recorded to the lowest weight, and details of injury. There were 10 males and four females with a mean age of 11.24 years (+/- 5.5). Mean injury scores included ISS 24.24 +/- 5.96, PTS 4.8 +/- 1.7, and TSS 11.79 +/- 2.78. The closest Theoretical Caloric Requirement (ThCR) that would have produced the Cumulative Caloric Deficit was calculated from the actual weight loss and Caloric Intake. Eighty-six per cent of the ThCR were less than or equal to the 1989 Recommended Dietary Allowances (RDA) (mean -16.43 +/- 24%). The per cent increase of the ThCR above the basal was significantly higher for lower ISS scores (P < 0.05). When compared to RDA, the per cent change of the ThCR for mild injuries were 1.8 +/- 27.9% above the RDA and were 26.5 +/- 17.2% below the RDA for the severe injuries. These findings are consistent with the child with milder injuries resuming activity and the growth process earlier than a severely injured child. We would recommend calculating caloric requirements based on the RDA for milder injuries and on 0.75 RDA for the more severely injured child (ISS > 25).
Laparoscopic appendectomy, is it worth it?
The recent experience with open appendectomy was compared to our initial experience with laparoscopic appendectomy. Thirty-eight patients had open appendectomy for acute appendicitis. Two major and four minor complications occurred. Concurrently, 39 patients had laparoscopic appendectomy. There was one major and one minor complication. Of the laparoscopic patients, 69% received less than 24 hours of parenteral postoperative analgesia, compared to 44% of the patients in the open group. Fifteen of 39 laparoscopic patients (38%) were discharged within 24 hours of operation versus 3 of 38 (8%) in the open group. Total mean hospital cost for the laparoscopic group, $7,500, was significantly greater than for the open group, $5,700, because of increased laparoscopic equipment charges. Both open and laparoscopic appendectomy procedures were performed with minimal morbidity. The benefits of laparoscopy were earlier hospital discharge and less parenteral analgesic use, but it was significantly more expensive.
A new device for securing meshed split-thickness skin grafts.
This report describes the design, operation, and biomechanical performance of the Auto Suture Multifire Graftac-S disposable surgical staplers and absorbable tacks. The performance of this reloadable stapler has been compared to that of the Auto Suture Multifire Premium disposable skin stapler. The Premium stapler forms stainless steel staples to close the wound. The Graftac-S ejects absorbable tacks into the graft from a cartridge, which can be reloaded during a single operation. In two clinical trials of 10 patients each, the Graftac-S delivered absorbable tacks which were biocompatible and successfully secured the graft to the wound. The most obvious advantage of this device is that it obviates the need to remove the staples from the wound later. By the tenth postoperative day, about 90% of the tacks had extruded spontaneously, thereby reducing the amount of postoperative care required; discomfort to the patient during removal of the stainless steel staples is eliminated.
Tumor necrosis factor-induced mortality is reversed with cyclooxygenase inhibition.
OBJECTIVE: The authors hypothesized that TNF would induce eicosanoid synthesis, and a cyclooxygenase inhibitor would attenuate both eicosanoid synthesis and improve survival in an LD90 TNF-induced (150 ng/kg/i.v./5 min) mortality model. SUMMARY BACKGROUND DATA: Tumor necrosis factor is a cardinal mediator in sepsis; however, little is known about its effects on arachidonate metabolism. METHODS: Conscious male rats with carotid arterial and jugular venous catheters were randomized for mortality: group I, TNF alone (150 kg/i.v./15 min, n = 30); group II, ibuprofen (30 mg/kg/i.v. at t = -20 and +240 min), plus TNF, (n = 28); and for hemodynamics, eicosanoid synthesis, blood gases: group III, TNF alone, (n = 8); group IV, ibuprofen + TNF (n = 8); group V, monoclonal antibody to TNF plus TNF (n = 8). Mortality was determined at 4-72 hr. Other parameters determined over 4 hours (0, 5, 60, 120, 240 min). RESULTS: TNF stimulated synthesis of (a) TXB2 (71 +/- 30 pg/ml, mean +/- SE at base vs. 117 +/- 18 at 4 hr, p < 0.02); (b) PGE2 (70 +/- 6 pg/ml at base vs. 231 +/- 68 at 4 hr, p < 0.02); (c) 6PGF (52 +/- 6 pg/ml at base vs. 250 +/- 80 at 4 hr, p < 0.02). Ibuprofen significantly (p < 0.05) inhibited eicosanoid synthesis from TNF. TNF-induced mortality (87%, 26/30) was dramatically decreased with ibuprofen (11%, 3/28), at 4, 24, and 72 hr (p < 0.01). Monoclonal antibody to TNF prevented all abnormalities and had 100% survival. Hemodynamic events were similar in both groups, but metabolic acidosis was attenuated with ibuprofen. CONCLUSIONS: TNF stimulates arachidonic acid metabolism in vivo. A cyclooxygenase inhibitor attenuates eicosanoid synthesis and dramatically improves survival. TNF appears to have different effect on tissues that synthesize certain eicosanoids. Hypotension from TNF is not mediated via the eicosanoids. TNF-induced mortality, like endotoxemia/sepsis may be mediated, in part, via arachidonic acid metabolites. These new findings support the notion that cyclooxygenase inhibitors may be used as adjunctive therapy in clinical sepsis.
Penetrating thermal vascular injury in a child: a case report.
Penetrating vascular trauma in children is most commonly seen in wartime settings or more recently as a result of attempts at invasive imaging. Treatment of these patients can be more complicated than treatment of trauma in adults and must include maintenance of symmetric limb growth, compensatory growth of the vascular graft and its anastomoses, and the need for very long-term graft patency. This report describes the care of a 5-year-old child who was impaled by a hot metal pipe and sustained a penetrating thermal injury to the distal external iliac artery and vein. Issues such as conduit choice, extraanatomic reconstruction, anastomotic suture technique, and soft tissue coverage are reviewed in the report.
Necrotizing enterocolitis in multiple-birth infants.
Over a 5-year period, 20 infants of multiple-gestation births (16 twin, 2 triplet) developed necrotizing enterocolitis (NEC) (15 infants) or suspected NEC (5 infants). During the same period, 532 infants of multiple gestations were admitted to our neonatal intensive care unit, yielding a NEC incidence in this population of 3.8%. In two twin sets, both infants developed NEC or suspected NEC, and in three sets only the affected twin was transferred to our nursery. Five infants required surgical intervention (25%) and three infants died (overall mortality, 15%). Fifteen siblings who did not develop NEC served as a control group. Analysis showed that the 1-minute Apgar score was the most significant factor in predicting NEC (P less than .028) and need for surgical intervention (P less than .020). In this series, 82% of the infants with 1-minute Apgar less than 6 developed NEC, whereas 31% with 1-minute Apgar greater than 6 developed NEC.
Indications for placement of drains in the splenic fossa.
Drainage of the splenic fossa has for years remained a controversial issue. A large potential space exists in the left hypochondrium following splenectomy. Proponents of the use of drainage maintain that drainage is safe, efficacious in removal of blood, serum, and pancreatic enzymes, and carries little, if any, risk of subsequent infectious morbidity. Critics of the use of drainage cite the heretofore reported high incidence of subphrenic abscess formation in those patients in whom drains are placed as the reason for abandoning routine or therapeutic drainage of the splenic fossa.
In vitro effects of complement inactivation upon burn-associated cell-mediated immunosuppression.
Serum of severely burned patients possesses in vitro capacity to suppress cell-mediated immunologic responses. Failure to establish immune competence is predictive of mortality, usually from sepsis. In this investigation, the hypothesis that complement fragments, known to be elevated in the acute phases of burn injury, contribute to this suppression is tested. Serum taken from patients with massive (greater than 60%) and major (less than or equal to 60%) burn injury was analyzed for the ability to suppress mitogen-induced lymphocyte blastogenesis before and after exposure of the burn serum to (complement inactivating) temperatures. All patients in this study had immune suppressive serum. Heat inactivation partially restored immune competence in the serum of all patients, though significantly more so in patients with major burns compared with those with massive burns. Complement appears to play a contributory role in the acute stages of burn-induced, cell-mediated immunosuppression, though its role in patients with massive burn injury is overshadowed by the presence of serologic suppressive factors not present (or present in lower concentration) in patients with major burns.
Effects of fibrinogen degradation fragments D and E on cell-mediated immunity.
Serum taken from severely traumatized victims suppresses in vitro the response of normal lymphocytes to the mitogenic stimulant phytohemagglutinin (PHA). In the postburn period, fibrin degradation products (fragments D and E) are elevated in a high percentage. Controversy exists as to whether these fragments contribute to what is clinically evident as cell-mediated immune (CMI) suppression. Purified fragments D and E were isolated over an ion exchange cellulose column after activating, with streptokinase, a solution containing fibrinogen and plasminogen. Lymphocytes from six volunteers were cultured with PHA and serial dilutions of fragments D and E; each was analyzed for ability to incorporate radiolabeled thymidine. Fragment E possessed in vitro CMI suppression at pharmacologic doses. Fragment D demonstrated immune suppressive capabilities at doses approximating those estimated to occur in the acute postburn phases of injury.
Immediate prediction of blood requirements in trauma victims.
Current recommendations for the management of trauma victims include immediate crossmatching of 4 to 6 units of blood. Unused crossmatched blood is withdrawn from the available blood pool for 48 hours and costs the patient $33 per unit. Growing blood shortages and increasing laboratory costs demand reexamination of this practice. The purpose of this study was to examine blood usage in trauma victims and to develop new guidelines for emergency room requests for blood. The following clinical variables were reviewed in 250 trauma victims to determine their value as predictors of blood usage: age, sex, mechanism of injury, initial vital signs, trauma score (TS), and injury severity score (ISS). The best predictor of blood use was the trauma score. Of the total group, 71% had a TS greater than 14; 91% of these patients did not require transfusion. Twenty-eight percent of the total group had a TS equal to or less than 14; 70% of these patients did require transfusion. The data strongly suggest that type and screen can safely replace type and crossmatch as the initial blood bank requests in patients with trauma scores greater than 14. Blood requirements in patients with a trauma score less than or equal to 14 continue to warrant immediate crossmatching.
Artificial dermis for major burns. A multi-center randomized clinical trial.
This communication presents an 11-center prospective randomized trial using the artificial dermis invented by Burke and Yannas. Patients with life-threatening burns who underwent primary excision and grafting within 7 days of injury had comparable sites randomized to receive either the artificial dermis (study site) or the investigator's usual skin grafting material (control site). Control materials were autograft, allograft, xenograft, or a synthetic dressing. Epidermal grafts were applied to the study site during a second operation, and surviving patients were followed for 1 year after grafting. One hundred thirty-nine sites on 106 patients were studied. Mean burn size was 46.5 +/- 15% mean total body surface (TBSA). Overall mortality was 13%, and mean hospital stay was 68 +/- 45 days. Median artificial dermis take was 80% compared with 95% for all comparative sites, but the take was equivalent to that of all nonautograft control materials. Results with the artificial dermis improved slightly as the investigators became more familiar with the material. Donor site thickness for the study site averaged .006'' +/- .002'' compared to .013'' +/- .018'' for control (p less than .0001) and the epidermal donor site healed an average of 4 days sooner (10 +/- 6 vs. 14 +/- 8 days) (p less than .0001). As the wounds matured during the first year, both patients and surgeons felt that both sites became more comparable in appearance and function. At the completion of the study, there was less hypertrophic scarring of the artificial dermis, and more patients preferred the artificial dermis to the control graft. Artificial dermis with an epidermal graft provides a permanent cover that is at least as satisfactory as currently available skin grafting techniques, and uses donor grafts that are thinner and donor sites that heal faster.