Role of ancillary techniques in profiling unclassified laryngeal malignancies

Laryngeal biopsies, contrary to biopsies from many other sites of the body, very often contain minute amounts of tumour tissue that may consist of morphologically undifferentiated tumour only. In haematoxylin- and eosin-stained sections, there may be no indicative features of what specific tumour entity that is present. In the larynx, particularly small round cell neoplasms, primary or metastatic, often cause a diagnostic dilemma and where an incorrect diagnosis can induce substantial clinical consequences for the patient (e.g., primary neuroendocrine carcinomas vs metastatic variants, certain sarcomas). If sufficient/representative material has been obtained, the application of immunohistochemistry and/or molecular techniques should in virtually every case reveal the true nature of the malignancy. In cases with sparse amount of material, and therefore a limited number of sections to be cut, a careful and thoughtful stepwise approach is necessary to ascertain a reliable diagnosis, or at least guide the clinician to the most likely diagnoses. With today's advanced and widely available technology with an abundance of markers to discriminate different tumours, the use of the term "undifferentiated" should be largely unnecessary. In the exceptional, and indeed exceedingly rare cases, when a classification is not possible, even after repeat biopsy, we suggest that the laryngeal neoplasm is better termed "unclassified malignant neoplasm" rather than "undifferentiated malignant neoplasm".

Dorsomedial hypothalamus mediates autonomic, neuroendocrine, and locomotor responses evoked from the medial preoptic area

Previous studies suggest that sympathetic responses evoked from the preoptic area in anesthetized rats require activation of neurons in the dorsomedial hypothalamus. Disinhibition of neurons in the dorsomedial hypothalamus in conscious rats produces physiological and behavioral changes resembling those evoked by microinjection of muscimol, a GABA(A) receptor agonist and neuronal inhibitor, into the medial preoptic area. We tested the hypothesis that all of these effects evoked from the medial preoptic area are mediated through neurons in the dorsomedial hypothalamus by assessing the effect of bilateral microinjection of muscimol into the DMH on these changes. After injection of vehicle into the dorsomedial hypothalamus, injection of muscimol into the medial preoptic area elicited marked increases in heart rate, arterial pressure, body temperature, plasma ACTH, and locomotor activity and also increased c-Fos expression in the hypothalamic paraventricular nucleus, a region known to control the release of ACTH from the adenohypophysis. Prior bilateral microinjection of muscimol into the dorsomedial hypothalamus produced a modest depression of baseline heart rate and body temperature but completely abolished all changes evoked from the medial preoptic area. Microinjection of muscimol just anterior to the dorsomedial hypothalamus had no effect on autonomic and neuroendocrine changes evoked from the medial preoptic area. Thus, activity of neurons in the dorsomedial hypothalamus mediates a diverse array of physiological and behavioral responses elicited from the medial preoptic area, suggesting that the latter region represents an important source of inhibitory tone to key neurons in the dorsomedial hypothalamus.

Detecting genetic predisposition for complicated clinical outcomes after burn injury

Sepsis, septic shock and organ failure are common among patients with moderate to severe burns. The inability of demographic and clinical factors to identify patients at high risk for such complications suggests that genetic variation may influence clinical outcome. Moreover, the genetic predisposition to death from infection has been estimated to be greater than for cardiovascular disease or cancer . While it is widely accepted that genetic factors influence many complex disease processes, controversy has emerged regarding the most appropriate methods for detection and even the validity of many published allelic associations . This article will review the few studies of genetic predisposition that have been conducted in the setting of burn injury, then discuss some of the obstacles and potential approaches for the discovery of additional allelic associations.

Microinjection of prostaglandin E2 and muscimol into the preoptic area in conscious rats: comparison of effects on plasma adrenocorticotrophic hormone (ACTH), body temperature, locomotor activity, and cardiovascular function

The preoptic area (POA) is thought to play an important role in thermoregulation and fever. Local application of prostaglandin E2 (PGE2) to this region elicits increases in core body temperature, heart rate, and plasma levels of adrenocorticotrophic hormone (ACTH). Similar effects on body temperature and heart rate have also been reported after local application of the GABAA receptor agonist muscimol to the preoptic area. The purpose of this study was to assess and compare the effects of microinjection of PGE2 and muscimol into the preoptic area in the same chronically instrumented conscious rats on plasma levels of ACTH. Injection of either PGE2 (150 pmol/100 nL) or muscimol (20 or 80 pmol/100 nL) into the same sites in the preoptic area evoked increases in body temperature, heart rate, blood pressure, and plasma levels of ACTH, while significant increases in locomotor activity were apparent only after muscimol. These data confirm and extend previous findings and support the notion that neurons in the region of the preoptic area exert tonic inhibition on downstream mechanisms capable of increasing the activity of the hypothalamic-pituitary-adrenal (HPA) axis as well as sympathetic thermogenic and cardiac activity.

TLR4 and TNF-alpha polymorphisms are associated with an increased risk for severe sepsis following burn injury

CONTEXT

Sepsis, organ failure, and shock remain common among patients with moderate to severe burn injuries. The inability of clinical factors to identify at-risk patients suggests that genetic variation may influence the risk for serious infection and the outcome from severe injury.

OBJECTIVE

Resolution of genetic variants associated with severe sepsis following burn injury.

PATIENTS

A total of 159 patients with burns > or =20% of their total body surface area or any smoke inhalation injury without significant non-burn related trauma (injury severity score (ISS)> or =16), traumatic or anoxic brain injury, or spinal cord injury and who survived more than 48 h post-admission.

METHODS

Candidate single nucleotide polymorphisms (SNPs) within bacterial recognition (TLR4 +896, CD14 -159) and inflammatory response (TNF-alpha -308, IL-1beta -31, IL-6 -174) loci were evaluated for association with increased risk for severe sepsis (sepsis plus organ dysfunction or septic shock) and mortality.

RESULTS

After adjustment for age, full-thickness burn size, ethnicity, and gender, carriage of the TLR4 +896 G-allele imparted at least a 1.8-fold increased risk of developing severe sepsis following a burn injury, relative to AA homozygotes (adjusted odds ratio (aOR) 6.4; 95% confidence interval (CI) 1.8 to 23.2). Carriage of the TNF-alpha -308 A-allele imparted a similarly increased risk, relative to GG homozygotes (aOR = 4.5; 95% CI 1.7 to 12.0). None of the SNPs examined were significantly associated with mortality.

CONCLUSIONS

The TLR4 +896 and TNF-alpha -308 polymorphisms were significantly associated with an increased risk for severe sepsis following burn trauma.

Sentinel Lymph Node Biopsy Identifies Occult Nodal Metastases in Patients with Marjolinʼs Ulcer

Since Marjolin's description, the management of burn scar carcinoma has remained controversial. A multitude of options and recommendations exist for the management of both primary lesions and regional nodal metastasis. This work reviews six cases of Marjolin's ulcer staged using sentinel lymph node biopsy. All primary lesions were confirmed to be squamous cell carcinoma and occurred a median of 29.5 years after burn. No patient had clinically detectable lymphadenopathy. In all cases, preoperative lymphoscintigraphy successfully identified a single draining regional nodal basin. Subsequent intraoperative lymphatic mapping/sentinel lymph node (SLN) biopsy was successful in five of six cases (83%). A successful intraoperative lymphatic mapping/SLN biopsy was defined as the identification of blue (uptake of isosulfan blue dye) or "hot" (uptake of radiolabeled sulfur colloid as measured with a handheld gamma counter) node(s) and subsequent excision. Four of five SLN biopsies identified previously occult nodal metastasis. SLN biopsy represents a minimally invasive and accurate staging procedure for Marjolin's ulcer.

Serial Measurements Increase the Accuracy of Laser Doppler Assessment of Burn Wounds

Traditional methods of judging burn depth by clinical evaluation of the wound based on appearance and sensation remain in wide use but are subject to individual variation by examiner. In addition to the clinical difficulties with burn wound management, observer dependency of wound assessment complicates clinical trials of burn wound therapy. A laser Doppler flowmeter with a multichannel probe was used to measure burn wound perfusion as a tool to predict wound outcome. Serial measurement with laser Doppler flowmetry had an 88% specificity and a positive predictive value of 81% for identifying nonhealing wounds. These results suggest that laser Doppler flowmetry is a potentially useful tool for burn wound assessment.

A multicenter review of toxic epidermal necrolysis treated in U.S. burn centers at the end of the twentieth century

Toxic epidermal necrolysis (TEN) is a potentially fatal disorder that involves large areas of skin desquamation. Patients with TEN are often referred to burn centers for expert wound management and comprehensive care. The purpose of this study was to define the presenting characteristics and treatment of TEN before and after admission to regional burn centers and to evaluate the efficacy of burn center treatment for this disorder. A retrospective multicenter chart review was completed for patients admitted with TEN to 15 burn centers from 1995 to 2000. Charts were reviewed for patient characteristics, non-burn hospital and burn center treatment, and outcome. A total of 199 patients were admitted. Patients had a mean age of 47 years, mean 67.7% total body surface area skin slough, and mean Acute Physiology and Chronic Health Evaluation (APACHE II) score of 10. Sixty-four patients died, for a mortality rate of 32%. Mortality increased to 51% for patients transferred to a burn center more than one week after onset of disease. Burn centers and non-burn hospitals differed in their use of enteral nutrition (70 vs 12%, respectively, P < 0.05), prophylactic antibiotics (22 vs 37.9%, P < 0.05), corticosteroid use (22 vs 51%, P < 0.05), and wound management. Age, body surface area involvement, APACHE II score, complications, and parenteral nutrition before transfer correlated with increased mortality. The treatment of TEN differs markedly between burn centers and non-burn centers. Early transport to a burn unit is warranted to improve patient outcome.

Repeated injury to the lumbar nerve roots produces enhanced mechanical allodynia and persistent spinal neuroinflammation

STUDY DESIGN

A lumbar radiculopathy model investigated pain behavioral responses after nerve root reinjury.

OBJECTIVES

To gain a further understanding of central sensitization and neuroinflammation associated with chronic lumbar radiculopathy after repeated nerve root injury.

SUMMARY OF BACKGROUND DATA

The pathophysiologic mechanisms associated with chronic radicular pain remain obscure. It has been hypothesized that lumbar root injury produces neuroimmunologic and neurochemical changes, sensitizing the spinal cord and causing pain responses to manifest with greater intensity and longer duration after reinjury. However, this remains untested experimentally.

METHODS

Male Holtzman rats were divided into two groups: a sham group having only nerve root exposure, and a chromic group in which the nerve root was ligated loosely with chromic gut suture. Animals underwent a second procedure at 42 days. The chromic group was further divided into a reinjury group and a chromic-sham group, in which the lumbar roots were only re-exposed. Bilateral mechanical allodynia was continuously assessed throughout the study. Qualitative assessment of spinal cord glial activation and IL-beta expression was performed.

RESULTS

Mechanical allodynia was significantly greater on both the ipsilateral and contralateral sides after reinjury (P < 0.001), and the response did not return to baseline after reinjury, as it did with the initial injury. There were also persistent spinal astrocytic and microglial activation and interleukin-1beta expression.

CONCLUSIONS

The bilateral responses support central modulation of radicular pain after nerve root injury. An exaggerated and more prolonged response bilaterally after reinjury suggests central sensitization after initial injury. Neuroinflammatory activation in the spinal cord further supports the hypothesis that central neuroinflammation plays an important role in chronic radicular pain.

Differential activation of coronary and pulmonary endothelial cells by thermal injury

Remote organ dysfunction during resuscitation of severe thermal injury is characterized by early, transient pulmonary insufficiency and cardiac contractile dysfunction. Thermal injury is typified by profound systemic alterations of endothelial immunological, vasoactive, and barrier functions. The unique location of this ubiquitous, fragile monolayer makes it vulnerable to circulating serum factors created at remote cutaneous wounds. We examined endothelial "activation" in 2 distinct cell types, human coronary and pulmonary endothelial cells (EC), after severe thermal injury. By using human serum isolated at specific times after thermal injury ("early" [2 h post-burn] or "late" [26 h post-burn]), the endothelial release of vasoactive mediators, ICAM-1 expression, and monolayer permeability were assessed in vitro. Early burn serum enhanced coronary EC vasoconstrictor (ET-1) release and ICAM expression, inhibited vasodilator (PGI2) release, but had no effect on permeability. Conversely, under similar conditions, pulmonary EC PGI2 release and permeability were enhanced, ET-1 release was diminished, but ICAM was unaffected. Late burn serum enhanced vasodilator (NO) release and permeability to albumin in both coronary and pulmonary EC, whereas ET-1 release was inhibited. Under these conditions, only pulmonary ICAM expression was significantly enhanced. These data suggest that human endothelium isolated from divergent vascular beds are activated by burn injury in a unique manner for time post-burn and vascular site of cell origin.

Magnetic resonance imaging of the ovary

Magnetic resonance imaging (MRI) of the pelvis can characterize a wide variety of ovarian lesions. We discuss MRI strategies for identification and characterization of ovarian neoplasms and correlate MRI findings with lesion gross pathological and histopathological structure.

Objective estimates of the incidence and consequences of multiple organ dysfunction and sepsis after burn trauma

BACKGROUND

Organ dysfunction and sepsis are frequent after major burn trauma, represent quantifiable consequences of the systemic response to injury, and may be important end points by which to measure treatment effectiveness. However, standard and widely applied methods for their measurement have not been applied to burn trauma victims. Therefore, the purpose of this study was to quantify these complications after burn trauma.

METHODS

Patients with > or = 20% total body surface area burns admitted to a single center were prospectively enrolled. Standard sepsis criteria and multiple organ dysfunction (MOD) scores for the pulmonary, renal, cardiovascular, hepatic, and hematologic systems were determined. The incidence and risk factors for severe MOD (cumulative MOD score > or = 6) and severe sepsis were determined. The relationships between these complications and mortality and resource utilization were examined by univariate and multivariate analyses.

RESULTS

A total of 85 patients were enrolled over 1 year. Severe MOD developed in 24 (28%) and severe sepsis or septic shock developed in 12 (14%). Both were associated with increasing age and burn size and were more likely to occur in men. Most patients who developed severe MOD or severe sepsis survived (71% and 67%, respectively), and both were associated with longer intensive care unit stays and duration of mechanical ventilation.

CONCLUSION

According to simple and objective scoring systems, severe MOD and severe sepsis/septic shock are both related to burn size, age, and male sex. Both are related to intensive care unit length of stay and duration of mechanical ventilation.

Ovarian teratomas: tumor types and imaging characteristics

Ovarian teratomas include mature cystic teratomas (dermoid cysts), immature teratomas, and monodermal teratomas (eg, struma ovarii, carcinoid tumors, neural tumors). Most mature cystic teratomas can be diagnosed at ultrasonography (US) but may have a variety of appearances, characterized by echogenic sebaceous material and calcification. At computed tomography (CT), fat attenuation within a cyst is diagnostic. At magnetic resonance (MR) imaging, the sebaceous component is specifically identified with fat-saturation techniques. The US appearances of immature teratoma are nonspecific, although the tumors are typically heterogeneous, partially solid lesions, usually with scattered calcifications. At CT and MR imaging, immature teratomas characteristically have a large, irregular solid component containing coarse calcifications. Small foci of fat help identify these tumors. The US features of struma ovarii are also nonspecific, but a heterogeneous, predominantly solid mass may be seen. On T1- and T2-weighted images, the cystic spaces demonstrate both high and low signal intensity. Familiarity with the US, CT, and MR imaging features of ovarian teratomas can aid in differentiation and diagnosis.

An evaluation of risk factors for mortality after burn trauma and the identification of gender-dependent differences in outcomes

BACKGROUND

The primary objective of this study was to determine an objective method for estimating the risk of mortality after burn trauma, and secondarily, to evaluate the relationship between gender and mortality, in the setting of a quantifiable inflammatory stimulus. Previously reported estimates of mortality risk after burn trauma may no longer be applicable, given the overall reduction in case-fatality rates after burn trauma. We expect that future advances in burn trauma research will require careful and ongoing quantification of mortality risk factors to measure the importance of newly identified factors and to determine the impact of new therapies. Conflicting clinical reports regarding the impact of gender on survival after sepsis and critical illness may in part, be from different study designs, patient samples, or failure to adequately control for additional factors contributing to the development ofsepsis and mortality.

STUDY DESIGN

Data from the prospectively maintained burn registry for patients admitted to the Parkland Memorial Hospital burn unit between January 1, 1989 and December 31, 1998 were analyzed. Logistic regression was used to generate estimates of the probability of death in half of the study sample, and this model was validated on the second half of the sample. Risk factors evaluated for their relationship with mortality were: age, inhalation injury, burn size, body mass (weight), preexisting medical conditions, nonburn injuries, and gender.

RESULTS

Of 4,927 patients, 5.3% died. The best model for estimating mortality included the percent of total body surface area burned; the percent of full-thickness burn size; the presence of an inhalation injury; age categories of: < 30 years, 30 to 59 years, > or = 60 years; and gender. The risk of death was approximately two-fold higher in women aged 30 to 59 years compared with men of the same age.

CONCLUSIONS

We have provided a detailed method for estimating the risk of mortality after burn trauma, based on a large, contemporary cohort of patients. These estimates were validated on a second sample and proved to predict mortality accurately. We have identified an increased mortality risk in women of 30 to 59 years of age.

The fate of the coracoacromial ligament in arthroscopic acromioplasty: an anatomical study

This study defines the normal anatomical relationships among the coracoacromial ligament, the deltoid, and the acromion in cadavers. The effect of arthroscopic acromioplasty on the acromial attachments of the coracoacromial ligament and the anterior fibers of the deltoid was also studied. After arthroscopic acromioplasty, the fibers of coracoacromial ligament and overlying deltoid inserting into the anterior part of the acromion remained attached to the acromion by a bridge of tissue composed of periosteum and collagen fibers of the coracoacromial ligament and deltoid tendon. We have called this the coracoacromial-deltoid-periosteal complex; it has not previously been described. This study demonstrates that arthroscopic acromioplasty preserves the acromial attachment of the coracoacromial ligament and the anterior fibers of the deltoid.

Cardiovascular effect of 7.5% sodium chloride-dextran infusion after thermal injury

HYPOTHESIS

Clinical study can help determine the safety and cardiovascular and systemic effects of an early infusion of 7.5% sodium chloride in 6% dextran-70 (hypertonic saline-dextran-70 [HSD]) given as an adjuvant to a standard resuscitation with lactated Ringer (RL) solution following severe thermal injury.

DESIGN

Prospective clinical study.

SETTING

Intensive care unit of tertiary referral burn care center.

PATIENTS

Eighteen patients with thermal injury over more than 35% of the total body surface area (TBSA) (range, 36%-71%) were studied.

INTERVENTIONS

Eight patients (mean +/- SEM, 48.2% +/- 2% TBSA) received a 4-mL/kg HSD infusion approximately 3.5 hours (range, 1.5-5.0 hours) after thermal injury in addition to routine RL resuscitation. Ten patients (46.0% +/- 6% TBSA) received RL resuscitation alone.

MAIN OUTCOME MEASURES

Pulmonary artery catheters were employed to monitor cardiac function, while hemodynamic, metabolic, and biochemical measurements were taken for 24 hours.

RESULTS

Serum troponin I levels, while detectable in all patients, were significantly lower after HSD compared with RL alone (mean +/- SEM, 0.45 +/- 0.32 vs 1.35 +/- 0.35 microg/L at 8 hours, 0.88 +/- 0.55 vs 2.21 +/- 0.35 microg/L at 12 hours). While cardiac output increased proportionately between 4 and 24 hours in both groups (from 5.79 +/- 0.8 to 9.45 +/- 1.1 L/min [mean +/- SEM] for HSD vs from 5.4 +/- 0.4 to 9.46 +/- 1.22 L/min for RL), filling pressure (central venous pressure and pulmonary capillary wedge pressure) remained low for 12 hours after HSD infusion (P = .048). Total fluid requirements at 8 hours (2.76 +/- 0.7 mL/kg per each 1% TBSA burned [mean +/- SEM] for HSD vs 2.67 +/- 0.24 mL/kg per each 1% TBSA burned for RL) and 24 hours (6.11 +/- 4.4 vs 6.76 +/- 0.75 mL/kg per each 1% TBSA burned) were similar. Blood pressure remained unchanged, and serum sodium levels did not exceed 150 +/- 2 mmol/L (mean +/- SD) in either group.

CONCLUSIONS

The absence of deleterious hemodynamic or metabolic side effects following HSD infusion in patients with major thermal injury confirms the safety of this resuscitation strategy. Postburn cardiac dysfunction was demonstrated in all burn patients through the use of cardiospecific serum markers and pulmonary artery catheter monitoring. Early administration of HSD after a severe thermal injury may reduce burn-related cardiac dysfunction, but it had no effect on the volume of resuscitation or serum biochemistry values.

Thermal injury alters endothelial vasoconstrictor and vasodilator response to endotoxin

BACKGROUND

The unique location of the endothelium makes it vulnerable to injury from circulating factors created at remote wounds. In this study, we examined the effect of a sequential burn and lipopolysaccharide (LPS) challenge on endothelial function in vitro.

METHODS

Human umbilical vein endothelial cells treated with 20% human serum isolated from burn patients (>40% total burn surface area) at 2 and 24 hours postinjury. Cultures were subsequently treated with Escherichia coli LPS:0111:B4 (0.10-100ng/mL). Endothelin-1 (ET-1), 6-ketoPGF1a, and NO2/NO3 were detected by using specific enzyme immunoassays.

RESULTS

Burn serum did not alter endothelial ET-1, PGI2, or NO secretion compared with Control serum. LPS significantly enhanced 6-ketoPGF1a (54,242+/-14,466 pg/10(6) cells) and NO2/ NO3 (723+/-210 microM) secretion, but not ET-1 compared with Control serum alone (3,878+/-963 and 219+/-110). Burn serum pretreatment significantly enhanced the ET-1 response to LPS (303+/-36 pg/10(6) cells vs. 193+/-47). The 6-ketoPGF1a (16,509+/-3,785) and NO2/NO3 (354+/-98) responses to Burn/LPS were significantly diminished compared with Control/LPS. Although this level of 6-ketoPGF1a was elevated compared with Control alone (7,518+/-2,299), NO2/NO3 was unchanged (significance at p < 0.05).

CONCLUSION

Thermal injury may prime remote endothelium and alter the response to a septic focus with an enhanced vasoconstrictor (ET-1) and diminished vasodilator (PGI2/NO) response, a situation that may contribute to postburn distal organ injury.

Traumatic wound care

The scope and importance of traumatic wound care, assessment, debridement, pre and postoperative management, and subsequent skin care during the course of treatment cannot be over-emphasized, and indeed, are the most important considerations for functional and cosmetic outcome. Care begins in the emergent phase and continues through acute and convalescent phases. Efforts are directed at methods and techniques which prevent infection, facilitate wound healing, promote comfort, and at the same time, maintain optimal function and minimize deformities.

Identification and structural characterization of a novel member of the vitamin D binding protein family

The apparent high degree of homology of a blood protein with a unique dual binding affinity for two distinct hormones, thyroxin (T4) and vitamin D, isolated from a turtle, Trachemys scripta (Family Emydidae) and mammalian vitamin D binding protein (DBP) prompted further interspecific comparison to better understand the structure of functional binding sites. Using polymerase-chain reaction (PCR) with primers derived from the putative nucleotide sequences encoding peptides from the degradation of the T. scripta protein, we cloned the cDNA. The mature turtle protein contains 466 amino acids, about eight residues more than in mammalian DBP. The nucleotide sequence of the coding region showed 63% nucleotide and 73% amino acid homology (approximately 53% identity) to mammalian DBP (human, rat, mouse, and rabbit). However, there was no significant homology to mammalian T4-binding globulin (TBG) or transthyretin (TTR). Comparisons with mammals help define further the requirements for the vitamin D and actin binding sites. Northern blots of RNA isolated from turtle tissue probed with the 5' portion of cDNA established expression of the transcript in liver, kidney, and brain (in order of abundance), in contrast to mammal sequences in which expression of DBP is largely confined to the liver.

Evaluation of troponin-I as an indicator of cardiac dysfunction after thermal injury

BACKGROUND

Biochemical serum markers commonly used to assess human cardiac injury (creatinine phosphokinase, creatine phosphokinase-MB) have been shown to have diminished specificity for detection of cardiac injury in the setting of burn-related soft-tissue and skeletal muscle injury. Laboratory studies have demonstrated that severe cutaneous thermal injury is associated with cardiac contractile dysfunction and a corresponding elevation in serum cardiac troponin-I (cTn-I) in several species.

METHODS

Twenty-three patients admitted to a tertiary care burn referral center were evaluated. Patients were monitored with pulmonary artery catheters, and creatinine phosphokinase, creatine phosphokinase-MB, and cTn-I levels were determined for 24 hours. Using a database, 6,722 burn patients were reviewed to determine the incidence of preexisting cardiac disease and postburn cardiac complications.

RESULTS

All patients had persistent sinus tachycardia (>115 beats per minute) without obvious electrical anomalies. All patients centrally monitored with a pulmonary artery catheter (n=20) maintained a cardiac index of greater than 3.0 L x min(-1) x m(-2) x cTn-I was present (>0.3 ng/mL) within 3.0 hours and elevated (>0.55 ng/mL) at 24 hours for all burns of more than 18% total body surface area. Historically, although only 5% of all admissions manifest acute postburn cardiac complications, 94% of these patients presented with preexisting heart disease.

CONCLUSION

Severe thermal injury was associated with a mild elevation in serum troponin-I; however, this did not correlate with overt cardiac morbidity or mortality. Postburn elevation of cTn-I suggested that a subtle degree of cardiac injury was present after a severe thermal injury despite hyperdynamic cardiac function during resuscitation.

Tracheostomy in the young pediatric burn patient

OBJECTIVE

To evaluate the incidence of complications in comparison with the benefits of tracheostomy in young pediatric burn patients (newborn to 3 years old).

DESIGN

Retrospective survey.

SETTING

Tertiary care burn center.

PATIENTS

A total of 1549 consecutive pediatric burn patients, of whom 180 were intubated.

INTERVENTIONS

Tracheostomy was performed in 76 children.

MAIN OUTCOME MEASURES

Duration of mechanical ventilation, mortality, respiratory complications, airway complications, and condition of the airway at discharge from the hospital.

RESULTS

Seventy-six patients required tracheostomy. Their mean burn size was 34% total body surface area and mean length of stay in the hospital was 56 days. There were no perioperative complications. Eight patients (10%) could not be decannulated because of airway obstruction. Five of these outgrew their obstruction, 2 required surgery, and 1 continues to be evaluated for laryngeal reconstruction.

CONCLUSION

Pediatric tracheostomy can be performed safely with no perioperative complications and acceptable chronic morbidity.

Immunohistochemical analysis of gel-transferred cells in cytologic preparations following smear division

Fine-needle aspirations on solid tumors are used increasingly as a means of obtaining a primary diagnosis. In many cases, a panel of immunostains performed on these aspirates is necessary to further characterize the cytologic interpretation. The amount of material obtained through aspiration, however, is often quite limited and is present on few glass slides. Previous studies have demonstrated the success of dividing cytologic smear preparations into smaller parts that could then be used for a panel of immunohistochemical stains. These results, however, did not compare the immunoreactivities of various antibodies before and after tissue transfer on cytologic preparations. In the present study, 41 immunohistochemical stains that employed 16 antibodies on 15 tumor preparations were performed following smear partition using the tissue-transfer technique. The percentage of cells that stained positive after transfer was determined and was correlated quantitatively to the untransferred controls. Specific immunoreactivity was demonstrated in 30 of 38 cases (79%) but was significantly decreased or lost in 8 of 38 cases (21%), which included antibodies for S-100, estrogen and progesterone receptors, chromogranin, neuron-specific enolase, and cytokeratin. Morphology was well preserved following tissue transfer, although limited cytoplasmic damage was seen in up to 25% of tumor cells. Immunopositive samples were found to be easily interpretable. Because sporadic cases fail to show immunohistochemical staining reactions following cytologic smear division and transfer, negative immunohistochemical stains in such preparations should be approached with caution.

Unique cytomegalovirus intracytoplasmic inclusions in ectocervical cells on a cervical/endocervical smear

This case demonstrates unique cytomegalovirus (CMV)-associated intracytoplasmic inclusions in the intermediate squamous cells of a cervical/endocervical smear. These concentric, rod-shaped, perinuclear inclusions were stained for CMV by immunohistochemistry. Cytomegalovirus endocervicitis was also documented on a concurrent cervical biopsy. The finding of these characteristic inclusions on a routine endocervical/cervical smear may provide morphologic evidence for CMV infection in the absence of an adequate endocervical component.

Treatment of femur fracture with associated head injury

OBJECTIVES

The aim of this study was to determine (a) whether delay in femur fracture stabilization beyond twenty-four hours in patients with head injury increased the risk of pulmonary complications and (b) whether immediate (up to twenty-four hours) femur fracture stabilization increased the risk of central nervous system (CNS) complications.

DESIGN

Retrospective analysis.

MATERIALS AND METHODS

Thirty-two patients with femur fracture and head injury were identified. Fourteen underwent immediate stabilization of their fractures, and eighteen underwent delayed (four-teen patients) or no (four patients) stabilization of their fractures.

RESULTS

In the immediate stabilization group, five patients had severe head injuries [Glasgow Coma Score (GCS) < or = 8] and nine had mild head injuries (GCS > 8). In the mild head injury group, no patient had a pulmonary complication and one had a CNS complication. In the severely head-injured group, one patient had a pulmonary complication and no patient had a CNS complication. In the delayed stabilization group, six patients had mild head injuries (GCS > 8) and twelve had severe head injuries (GCS < or = 8). In the mildly head injured group, one patient had a pulmonary complication, two patients had CNS complications, and one patient died. In the severely head injured group, nine patients had pulmonary complications, three patients had CNS complications, and one patient died. Logistic regression identified delay in femur stabilization as the strongest predictor of pulmonary complication (p = 0.0042), followed by severity of chest Abbreviated Injury Score (AIS; p = 0.0057) and head AIS (p = 0.0133). Delaying fracture stabilization made pulmonary complications forty-five times more likely. Each point increase in the chest AIS and head/neck AIS increased the risk of pulmonary complication by 300 percent and 500 percent, respectively. A statistically significant predictor of CNS complications could not be identified by using logistic regression.

CONCLUSION

Delay in stabilization of femur fracture in head-injured patients appears to increase the risk of pulmonary complications. However, due to selection bias in this patient sample, this question cannot be definitively answered. Early fracture stabilization did not increase the prevalence of CNS complications.

Toxic epidermal necrolysis

Toxic epidermal necrolysis (TEN) is a poorly understood and devastating condition. It is usually diagnosed in a primary care setting. Treatment of severe cases by burn care personnel is usually by referral. In this review, we report excessive mortality rates associated with prolonged use of systemic steroid therapy and delayed referral (more than 1 week from diagnosis). Forty-four consecutive patients admitted to a regional burn center with the diagnosis of TEN over a 14-year period, (0.7% of all admissions) were included. Precipitating factors were identified in 30 cases. Twenty-one patients had known prehospital allergy conditions directly related to the inciting agent. The mean age of this population was 44.9 years, and the mean total body surface area (TBSA) injury was 52.4%. Eighty-four and one-half percent of all patients with TEN were admitted to the ICU. Twenty-four patients required ventilator support. Overall mortality rate was 36%. Nonsurviving patients had a mean age of 61.6 years, compared to 35.3 years for survivors. Nonsurvivors had a mean TBSA of 64.4%, survivors had a mean TBSA of 44%. TEN, although a nonthermal injury, is best managed by personnel experienced in the care of severe thermal injuries. Despite the availability of this expertise, delayed transfer of severe presentations continues to contribute to exceptionally high morbidity and mortality rates.

Glucocorticoid regulation of hepatic TNF production following cecal ligation and puncture sepsis

Tumor necrosis factor-alpha (TNF) is a critical early mediator in the genesis of a systemic inflammatory response during a septic insult. Many of the harmful effects evident during sepsis are ascribed to excessive endogenous TNF production. Because the liver is an important source of circulating TNF during endotoxicosis, and because glucocorticoids are believed to have a regulatory role in suppressing endogenous TNF production, we evaluated the effect of adrenalectomy on the hepatic production of TNF in an isolated perfused liver model after cecal ligation and puncture (CLP) sepsis. Fasted, male Holtzman rats (n = 4/group) underwent CLP alone, adrenalectomy (ADREX) alone, or CLP plus ADREX (CLP/ADREX). Two hours after the operation, the rat livers were explanted and perfused in an isolated recirculating model. Serum TNF levels were greater in CLP/ADREX rats than in both other groups. TNF production in the perfused liver was greater in the CLP/ADREX rats when compared with either CLP alone or ADREX alone. A separate mortality study was performed (N = 35) that demonstrated a CLP induced mortality of 45%, and a CLP/ADREX mortality of 100%. Thus, adrenalectomy increased circulating TNF and hepatic TNF production as well as mortality in CLP sepsis. These findings suggest an important role for endogenous glucocorticoids in modulating hepatic TNF production during CLP-induced sepsis.

Abundant synthesis of transthyretin in the brain, but not in the liver, of turtles

The binding of thyroxine to proteins in the blood plasma of the turtle, Trachemys scripta, was analyzed by incubation with radioactive thyroxine, electrophoresis and autoradiography. Albumin and an alpha-globulin were found to bind thyroxine; no thyroxine-binding transthyretin was detected in the prealbumin region. In contrast to blood plasma, a thyroxine-binding prealbumin was observed in medium from T. scripta choroid plexus incubated in vitro. RNA was extracted from brain tissue containing choroid plexus and from liver of T. scripta and Chelydra serpentina and analyzed by hybridization with transthyretin cDNA from the lizard Tiliqua rugosa. The brain RNAs contained substantial amounts of transthyretin mRNA, whereas only trace amounts of transthyretin mRNA were detected in RNA from liver. No transthyretin mRNA was observed in RNA from kidney. The results support the hypothesis that the expression of the transthyretin gene first evolved in the choroid plexus of the brain at the stage of the stem reptiles, whereas abundant transthyretin synthesis in liver evolved much later, and independently, in mammals and birds.

A multicenter clinical trial of a biosynthetic skin replacement, Dermagraft-TC, compared with cryopreserved human cadaver skin for temporary coverage of excised burn wounds

This multicenter study compared the use of a biosynthetic human skin substitute with frozen human cadaver allograft for the temporary closure of excised burn wounds. Dermagraft-TC (Advanced Tissue Sciences, Inc.) (DG-TC) consists of a synthetic material onto which human neonatal fibroblasts are cultured. Burn wounds in 66 patients with a mean age of 36 years and a mean burn size of 44% total body surface area (28% total body surface area full-thickness) were surgically excised. Two comparable sites, each approximately 1% total body surface area in size, were randomized to receive either DG-TC or allograft. Both sites were then treated in the same manner. When clinically indicated (> 5 days after application) both skin replacements were removed, and the wound beds were evaluated and prepared for grafting. DG-TC was equivalent or superior to allograft with regard to autograft take at postautograft day 14. DG-TC was also easier to remove, had no epidermal slough, and resulted in less bleeding than did allograft while maintaining an adequate wound bed. Overall satisfaction was better with DG-TC.

Alcohol, drug intoxication, or both at the time of burn injury as a predictor of complications and mortality in hospitalized patients with burns

The objective of this study was to characterize the association between drug and alcohol intoxication at the time of injury and subsequent complications and mortality in hospitalized patients with burns. A computerized burn database was used to analyze data on 3047 consecutive adult (21 to 75 years) hospitalized patients with burns admitted between January 1982 and August 1994. Data for intoxicated (by history, blood alcohol content, or positive drug screen) and nonintoxicated patients were compared. The same analysis was also conducted on 429 consecutive adolescent patients with burns (ages 14 to 20 years) admitted during the same time period. The incidence of intoxication at the time of burn was 6.9%. No significant differences in age, sex, race, or burn size were noted. Intoxicated patients had a higher incidence of associated injuries. Skin graft loss, cellulitis, donor site conversion, hypotension, and pneumonia were more common in the intoxicated group. They also had more intensive care unit admissions, ventilator days, operations, transfusions, and total hospital days. Intoxicated patients had a lower mortality (7.1%) than patients in the control group (10.9%). Intoxication at the time of burn injury is an important predictor of complications in adult patients with burns.

Antidepressant deaths by overdose

OBJECTIVE

To determine the prevalence of antidepressant deaths in South Australia, the relative frequency of each antidepressant used and demographic data of those who died.

METHOD

This was a retrospective, case note study of all cases where death was caused by lethal levels of antidepressants in South Australia for the period from 1986 to 1990. The study occurred at the South Australian coroner's office. Subjects were selected from toxicology data, where serum or liver levels of one or more antidepressant were in the lethal range.

RESULTS

Seventy-one cases were identified and information was obtained on 68 of these cases from the coroner's files. Amitriptyline, Doxepin and Dothiepin accounted for the majority of antidepressant deaths. Women were 2.5 times more likely to use antidepressants to suicide than men. At least 63% had a known psychiatric illness and 45% had previously attempted suicide.

CONCLUSIONS

The older tricyclic antidepressants are a significant cause of suicide. It is recommended that the newer antidepressants, which are as efficacious yet safer in overdose, be prescribed in preference to the older tricyclic antidepressants, as the first line of treatment in newly diagnosed depressed outpatients.

Treatment of femur fracture with associated vascular injury

OBJECTIVE

The aim of this study was to determine (1) if internal fixation was associated with a high amputation rate in patients with femur fracture and vascular injury; and (2) if patients who underwent internal fixation before vascular repair had a higher amputation rate.

DESIGN

This is a retrospective analysis.

MATERIALS AND METHODS

Twenty-six patients requiring femoral stabilization with injury to the superficial femoral artery, popliteal artery, or common femoral vein were studied. The Injury Severity Score and the Mangled Extremity Severity Score were calculated for each. Nineteen patients underwent internal fixation. Ten patients had internal fixation before vascular repair.

RESULTS

Sixteen of 19 patients treated with internal fixation had limb salvage. Nine of 10 patients who had internal fixation before vascular repair had limb salvage. Poor outcomes (gangrene, amputation, or death) were associated with a Mangled Extremity Severity Score > or = 6 (p = 0.005).

CONCLUSIONS

In these patients, poor outcome is associated with severe leg injury, (with a Mangled Extremity Severity Score of > or = 6). Internal fixation can be safely used, and skeletal stabilization can be safely performed before vascular repair. If ischemic time is prolonged, vascular shunts should be used until skeletal stabilization is completed.

Pediatric grease burn injury

OBJECTIVES

To evaluate the incidence and severity of grease and oil burns in children and to discuss prevention.

DESIGN

All pediatric patients admitted with hot grease burns were compared with the general pediatric burn population.

SETTING

All admissions to a regional burn center during a 20-year period were reviewed using a computerized database.

PATIENTS

Eight thousand three hundred sixteen patients with acute burn injuries were admitted. Children less than 15 years old accounted for 31.9% of this population (2651 patients). Two hundred fifteen children had burns caused by hot grease or oil.

INTERVENTIONS

Sixty-nine patients (32%) in the pediatric grease burn group were admitted to the intensive care unit. Thirteen patients (6%) required intubation, and six (46%) eventually required tracheostomy. Sixty-three patients (29.3%) required operative procedures for wound care.

MAIN OUTCOME MEASURES

Grease burn patients had a significantly higher incidence of full-thickness burns, wound infection, and burns involving the face, neck, chest, and arms but lower mortality compared with the general pediatric burn population. Fifty percent of grease burns were caused by home deep fryers.

RESULTS

There was no difference between the groups regarding age, sex, or ethnic distribution, size of injury, length of hospitalization, number of intensive care unit admissions, pulmonary infections, operative procedures, or mechanical ventilator requirements.

CONCLUSIONS

Grease burns often result in long-lasting, disfiguring, and debilitating injuries. Home deep fryers are frequently involved in these injuries. Careful use of these appliances is mandatory. Increased public awareness is vital to this effort.

High-voltage electric injury: assessment of muscle viability with MR imaging and Tc-99m pyrophosphate scintigraphy

PURPOSE

To evaluate use of magnetic resonance (MR) imaging and technetium-99m pyrophosphate (PYP) scintigraphy in preoperative assessment of muscle viability after high-voltage electric injury.

MATERIALS AND METHODS

Twelve injured limbs were studied. Immediate, equilibrium, and delayed Tc-99m PYP scintigrams and gadolinium-enhanced and unenhanced MR images were obtained. Imaging results were compared with clinical findings.

RESULTS

Scintigraphy demonstrated nonperfusion in four limbs that were subsequently amputated, but MR imaging had poor sensitivity in nonperfused regions owing to lack of edema. Tc-99m PYP uptake increased at transition zones between normal and nonperfused regions. MR imaging allowed further characterization of these zones by demonstrating edema as enhancing (perfused) or nonenhancing (nonperfused). In all nonamputated limbs, edema showed enhancement.

CONCLUSION

In high-voltage electric injury, gadolinium-enhanced MR imaging appears able to demonstrate zones of potential viability within radionuclide-avid tissue but has poor perfusion sensitivity when used alone.

Acute pseudo-obstruction in critically ill patients with burns

Acute pseudo-obstruction of the colon (Ogilvie's syndrome) is a rare but potentially morbid complication of burn injury. Two thousand seven hundred three consecutive critically ill patients with burns were reviewed for findings consistent with pseudo-obstruction. Eight (0.29%) patients were identified. Mean age was 63.5 years, and mean burn size was 24.6% total body surface area. All patients were undergoing mechanical ventilation at the time of diagnosis. Six had a previous cardiac condition or complication, and five were on digoxin. Diagnosis was suspected in seven patients before colonoscopy or surgery. Six patients were treated with colonoscopy alone with one treatment failure. Two deaths occurred during hospitalization. Two late deaths were due to underlying cardiac conditions. The preferred treatment of Ogilvie's syndrome is nasogastric suction, colonic decompression, and close observation with surgery reserved for treatment failures or when diagnosis is in doubt. The incidence of Ogilvie's syndrome in patients with burns appears to be related to nonburn medical conditions, especially cardiopulmonary complications and age, rather than to the burn itself.

Delayed hypertonic saline dextran administration after burn injury

OBJECTIVE AND DESIGN

Experimental studies in our laboratory showed that hypertonic saline dextran (HSD; 7.5 NaCl in 6% dextran 70) given as a small bolus (4 mL/kg) immediately after burn injury in guinea pigs improved cardiac contractile performance and reduced the total fluids requirements. Although these data confirm the cardioprotective effects of HSD given immediately postburn, prehospital and early inhospital management of severely burned patients consists of aggressive crystalloid fluid resuscitation to correct intravascular volume deficits. The question arose as to whether delaying HSD for several hours after initiating crystalloid resuscitation would provide cardioprotection.

MATERIALS AND METHODS

Third-degree scald burns comprising 45 +/- 1% of the total body surface area (burn groups, n = 40) or 0% for controls (group 1, n = 12) were produced; in groups 2 to 5, lactated Ringer's (LR) resuscitation was initiated immediately postburn according to the Parkland formula, 4 mL/kg/% burn. In group 2, (n = 12), LR was continued for 24 hours. HSD was administered as an i.v. bolus at either 1 hour (group 3, n = 10), 4 hours (group 4, n = 9), or 8 hours postburn (group 5, n = 9); immediately after HSD administration, LR was continued (1 mL/kg/% burn) until 24 hours postburn.

RESULTS

Compared to sham burn controls, hearts from burned animals treated with LR alone had significant cardiac dysfunction, as indicated by a lower left ventricular pressure and +/- dP/dt. Compared with hearts from LR-treated animals, hearts from burned animals treated with HSD 1 hour (HSD-1) and 4 hours (HSD-4) after burn injury had significantly higher LVP and +/- dP/dt. Ventricular function curves calculated for HSD-1 and HSD-4 groups were comparable to those calculated for hearts from sham burns. Delaying HSD administration until 8 hours after burn provided little cardioprotection.

CONCLUSIONS

Our data indicate that HSD effectively maintains cardiac function and reduces overall total fluid requirements if administered within 4 hours after burn injury.

Effects of propranolol administration on cardiac responses to burn injury

Previous studies showing that propranolol upregulates beta-adrenergic receptors and protects against myocardial ischemia led us to hypothesize that preburn propranolol would protect against postburn cardiac dysfunction. Guinea pigs were treated with propranolol 3 mg/kg/day for 14 days, then deeply anesthetized and subjected to a 45% 3 degrees scald burn; eight guinea pigs treated with propranolol served as the control group (group 1). Burned guinea pigs were resuscitated with Ringer's lactate given as either 4 ml (group 2, N = 8), 6 ml (group 3, N = 10), or 8 ml (group 4, N = 6) per kg/% burn. Guinea pigs treated for 14 days with vehicle (water) were subjected to either sham burn (non-propranolol control, group 5, N = 10) or burn and treatment (group 6, N = 10) as described for group 2. Fluid resuscitation in non-propranolol-treated guinea pigs failed to overcome burn-induced cardiac deficits, as indicated by significantly lower left ventricular pressure, 86 +/- 2 versus 62 +/- 3 mm Hg; +dP/dt max, 1365 +/- 43 versus 1110 +/- 44 mm Hg/sec; -dP/dt max, 1184 +/- 31 versus 881 +/- 40 mm Hg/sec, p < 0.001. Burn-mediated cardiac defects occurred in all propranolol-treated guinea pigs regardless of the fluid volume given. Our data show that (1) propranolol did not protect against burn-induced cardiac dysfunction, and (2) chronic beta-adrenergic blockade increases postburn fluid requirements for maintenance of cardiodynamic stability and for survival.

Acute adrenal insufficiency in the patient with burns

Acute adrenal insufficiency is an uncommon but devastating complication of severe burn injury. The diagnosis is rarely made antemortem. Acute, fatal, adrenal insufficiency developed in three patients among 807 critically ill patients with burns treated at this institution during the past 6 years. Thermal injuries elevate corticosteroid secretion for weeks after injury, severely stressing the adrenal glands. Overload of the hypothalamic-pituitary-adrenal axis is thought to make this system unusually vulnerable to acute infarction. Although the actual mechanism of adrenal hemorrhage is not clear, the combination of excessive adrenocorticotropic hormone stimulation and hemodynamic instability have been implicated in its evolution. Survival may be too short for characteristic Addisonian metabolic changes to develop. Acute adrenal insufficiency is a rare event that is historically associated with meningococcemia, although any life-threatening illness may precipitate this catastrophe. Therefore, when a sudden deterioration in the patient with thermal injuries is encountered, adrenal insufficiency must be considered.

The elderly burn patient

During a 16-year period, 547 patients who were older than 64 years of age with a mean total body surface area (TBSA) (third-degree burns) of 25% were treated. Etiologies were flame/flash in 81% of patients, scald in 11%, solids in 7%, and electrical/chemical in 1%. Seventeen percent of patients had significant causal factors. An inhalation injury was present in 13% of patients, and the mortality in these patients was 100%. Burn excision was performed 239 times in 165 patients. The majority of excisions were for full-thickness burns. Excision did not improve overall survival in patients with third-degree burns of 0% to 10%, but the length of stay (LOS) in excised and nonexcised survivors was improved (9 versus 21 days, respectively). The LOS and survival were not significantly different in patients with burns between 11% and 20%. Postburn complications occurred in 28% of patients. Overall mortality was 50% (mean age: 77 years; TBSA: 40%). There were no survivors with over 47% TBSA burns. The leading cause of death was pulmonary sepsis. Most surviving patients returned to a satisfactory lifestyle after discharge.