Kenneth E. Shepherd

Erythema induratum and active pulmonary tuberculosis

The etiology of erythema induratum, a rare disease of the skin in the United States but occasionally seen in natives of Asian countries, remains a source of debate. Its association with tuberculosis, although strongly suspected for more than one century, has not been clearly defined. We report a case of erythema induratum occurring in a young Chinese woman in the setting of active pulmonary tuberculosis. Both diseases promptly responded to antituberculous therapy. The diagnosis of erythema induratum should urge the clinician to search for a source of active tuberculosis, and treatment should be initiated accordingly.

Acute, subacute, and chronic histologic effects of simulated aspiration of a 0.7% sucralfate suspension in rats.

OBJECTIVE To assess the acute (4-hr), subacute (7-day), and chronic (21-day) effects of simulated aspiration of a 0.7% sucralfate suspension in rats. DESIGN Prospective, multigroup trial in which rats were randomized to various simulated aspiration groups. SETTING Experimental animal laboratory. SUBJECTS Forty-five Sprague-Dawley rats. INTERVENTIONS Simulated aspiration was induced by single, direct, tracheal instillation of 2 mL/kg of either room air, sucralfate, or normal saline. MEASUREMENTS AND MAIN RESULTS Lung histologic changes were assessed using a quantitative numerical scoring scale. There was an increase in bronchiolar inflammation in rats undergoing acute, simulated sucralfate aspiration compared with controls. There were no significant differences (p > .05) in any other features at any time interval studied (two-way analysis of variance). CONCLUSIONS Even though significant inflammatory airway lesions were produced in this acute model, these abnormalities resolved without evidence of subacute or chronic histologic progression. It remains to be determined if this pattern is unique to this specific experimental model or if it can be extrapolated to critically ill patients.

Elastin fibers and the diagnosis of bacterial pneumonia in the adult respiratory distress syndrome

OBJECTIVE It has been inferred from previous work that 40% potassium hydroxide preparations of lower respiratory tract secretions that demonstrate elastin fibers have a 100% specificity and positive predictive value in diagnosing bacterial pneumonia in intubated, mechanically ventilated patients without the adult respiratory distress syndrome (ARDS). Our aim was to assess the specificity of 40% potassium hydroxide preparations in diagnosing bacterial pneumonia in patients with ARDS and suspected pneumonia. DESIGN Prospective, case-referral clinical study. SETTING Referral hospital. PATIENTS Of 24 patients with ARDS who were intubated and mechanically ventilated with suspected bacterial pneumonia, 22 were assessable and evaluated for this report. INTERVENTIONS Tracheo-bronchial aspirates were obtained from all patients and analyzed for elastin fibers using 40% potassium hydroxide. MEASUREMENTS AND MAIN RESULTS Of the 22 assessable patients, ten patients did not have a complicating bacterial pneumonia. Six of these ten patients had potassium hydroxide preparations that demonstrated elastin fibers (false positives). The other four patients had preparations that did not demonstrate elastin fibers (true negatives). Specificity was 40%. CONCLUSION Elastin fiber preparations are not specific for diagnosing bacterial pneumonia in patients with ARDS.

Acute effects of sucralfate aspiration: clinical and laboratory observations.

STUDY OBJECTIVE To assess the complications associated with the aspiration of sucralfate. DESIGN Clinical (case report) and bench observations. SETTING Inpatient intensive care unit and experimental animal laboratory. SUBJECTS The case of a critically ill patient who aspirated sucralfate is presented. Fifteen Sprague-Dawley rats served as experimental animals to investigate the acute histologic effects of large-volume aspiration of sucralfate. INTERVENTIONS The patient underwent emergent intubation to relieve acute upper airway obstruction. All the animals were anesthetized and had tracheostomies performed. The experimental groups had acidic intratracheal injections of 2 ml/kg of a nonparticulate liquid (pH, 2.3; n = 6) or a sucralfate aspirate (1 ml/kg of a 5% sucralfate suspension of pH 3.6, followed by 1 ml/kg 0.1 of normal hydrochloric acid of pH 1.0; n = 4). Four hours after simulated aspiration, the rats were sacrificed and their lungs removed for histologic examination by light microscopy. MEASUREMENTS AND MAIN RESULTS Differences were noted in histopathologic injury in the experimental groups compared to the control group using a numeric scoring scale. Nonparticulate acidic liquid aspiration caused a significant increase (p < 0.05) in inflammation. Sucralfate caused a significant increase (p < 0.05) in lung hemorrhage. A nonsignificant trend was seen with simulated sucralfate aspiration for edema and inflammation. No long-term sequelae were attributed to the clinical aspiration episode. CONCLUSIONS Acute complications associated with aspiration of sucralfate have been identified. In the laboratory setting, simulated aspiration of sucralfate led to acute lung injury.

Acute histologic effects of simulated large-volume aspiration of sucralfate into the lungs of rats.

Sucralfate is an effective agent in reducing the incidence of upper GI tract (UGIT) stress bleeding and nosocomial pneumonia in critically ill patients. Many of these patients are not intubated and are at increased risk for aspiration of large volumes of UGIT contents containing sucralfate. The effects of aspirated sucralfate are unknown. To investigate this, large-volume aspiration (2 ml/kg) was simulated in freshly tracheostomized rats (n = 6, all experimental groups) using normal saline, particulate antacid, and sucralfate adjusted to pH 3.6 and 5.0. Four hours after aspiration, the rats were killed and their lungs were formalin-fixed. Significant increases in lung inflammation were seen by light microscopy in all experimental groups at pH 3.6. Antacid aspirated at pH 5.0 induced significant increases in airway as well as parenchymal inflammation. At pH 3.6, the antacid aspiration led to significant increases in lung edema and hemorrhage. Sucralfate aspiration produced significant increases in pulmonary hemorrhage at pH 5.0. Our microscopic findings are consistent with the acute pulmonary histopathologic changes known to occur after large-volume aspiration of particulate materials, including antacids. Additionally, we show that large-volume aspiration of sucralfate produced significant acute pneumonitis, including pulmonary hemorrhage. In view of the proven usefulness of sucralfate, further investigations are indicated to evaluate these experimental findings before extrapolating to critically ill patients.

Elastin fiber analysis in acute diffuse lung injury caused by smoke inhalation

OBJECTIVE The evaluation of various techniques to diagnose or exclude ventilator-associated bacterial pneumonia has been a focus of much research. One such technique involves elastin fiber detection. It has been inferred from previous work that 40% potassium hydroxide preparations of respiratory secretions that demonstrate elastin fibers have a 100% specificity in diagnosing bacterial pneumonia in intubated, mechanically ventilated patients without acute diffuse lung injury. The purpose of this investigation was to ascertain if elastin fibers might be detected in respiratory secretions in acute, diffuse lung injury in the absence of pneumonia (i.e., assess specificity). DESIGN An animal model using a standardized smoke inhalation protocol to cause acute, diffuse lung injury was used. MATERIALS AND METHODS Respiratory secretions collected from the endotracheal tubes from eight sheep that underwent the standardized smoke inhalation protocol and were examined with 40% potassium hydroxide. Histologic data were obtained from autopsy to diagnose or exclude lung injury and pneumonia. MEASUREMENT AND MAIN RESULTS We found six (false) positive elastin fiber preparations in the absence of histologic pneumonia. Specificity was 0.25. CONCLUSIONS We concluded that seeing these results, given a true specificity of 0.99 inferred from previous work, is highly improbable with a probability of 2.74 x 10(-7). Thus, elastin fiber analysis is likely to be highly nonspecific for diagnosing pneumonia in the setting of acute diffuse lung injury.

Postoperative Metastasis Risk: More Than Immunosuppression

assistance of the anesthesiologist(s) involved, most adverse events were self-reported by that practitioner. Also, the involved anesthesiologist(s) were generally present for the discussion and error analysis. Finally, the suggestion by Gauge that this peer review mechanism would be corrupted, if it were applied to patient compensation, is an interesting speculation. Perhaps, Gauge would be more comfortable with a no-fault system of medical liability. The stability with which all adverse outcomes occur suggests that this may also be a viable alternative. Hogan and Lavaruso wish to preserve and modify the present malpractice tort system. Their argument that the tort system should be preserved because it is our “best weapon in the battle for autonomy against managed care” must raise a smile on the faces of those who see similar value in both. As for their remaining arguments, the principles of scientific medicine are part of every medical school curriculum in the United States, and a stronger focus is being made on evidencebased medicine as we struggle to be cost effective. Increasing public exposure to courtroom proceedings, however, demonstrates that the legal system does not suffer from the same imposed cost constraints, nor does it adhere to the same scientific rigors. The lack of a response to the growing body of evidence that the tort system falls short of its goals is a good example. The suggestions for a Specialty Board of Legal Medicine and a Medical Malpractice Bar appear to offer a niche for a new breed of practitioner, but the legal profession should test these remedies with the same scientific principles and cost consciousness that the medical profession applies consistently.