RESUMEN

Habitat and biodiversity differences between matched pairs of organic and non-organic farms containing cereal crops in lowland England were assessed by a large-scale study of plants, invertebrates, birds and bats. Habitat extent, composition and management on organic farms was likely to favour higher levels of biodiversity and indeed organic farms tended to support higher numbers of species and overall abundance across most taxa. However, the magnitude of the response varied; plants showed larger and more consistent responses than other taxa. Variation in response across taxa may be partly a consequence of the small size and isolated context of many organic farms. Extension of organic farming could contribute to the restoration of biodiversity in agricultural landscapes.

Asunto(s)

RESUMEN

This position statement reviews several aspects of spirometric testing in the workplace, where spirometry is employed in the primary, secondary, and tertiary prevention of occupational lung disease. Primary prevention includes pre-placement and fitness-for-duty examinations as well as research and monitoring of health status in groups of exposed workers; secondary prevention includes periodic medical screening of individual workers for early effects of exposure to known occupational hazards; and tertiary prevention includes clinical evaluation and impairment/disability assessment. For all of these purposes, valid spirometry measurements are critical, requiring: documented spirometer accuracy and precision, a rigorous and standardized testing technique, standardized measurement of pulmonary function values from the spirogram, adequate initial and refresher training of spirometry technicians, and, ideally, quality assessment of samples of spirograms. Interpretation of spirometric results usually includes comparison with predicted values and should also evaluate changes in lung function over time. Response to inhaled bronchodilators and changes in relation to workplace exposure may also be assessed. Each of these interpretations should begin with an assessment of test quality and, based on the most recent ATS recommendations, should rely on a few reproducible indices of pulmonary function (FEV1, FVC, and FEV1/FVC.) The use of FEF rates (e.g., the FEF25-75%) in interpreting results for individuals is strongly discouraged except when confirming borderline airways obstruction. Finally, the use of serial PEF measurements is emerging as a method for confirming associations between reduced or variable pulmonary function and workplace exposures in the diagnosis of occupational asthma. Throughout this position statement, ACOEM makes detailed recommendations to ensure that each of these areas of test performance and interpretation follow current recommendations/standards in the pulmonary and regulatory fields. Submitted by the Occupational and Environmental Lung Disorder Committee on November 16,1999. Approved by the ACOEM Board of Directors on January 4,2000.

Asunto(s)

RESUMEN

Percutaneous endoscopic gastrostomy (PEG) tube placement is an established procedure in the nutritional management of patients. There are numerous reports in the literature describing the techniques for placing PEG tubes. However, there are few reports that discuss the proper methods for removing these devices and the complications that may result from incorrectly removing a PEG tube. An increasing number of patients with PEG tubes are being cared for by individuals who are not familiar with these devices and their proper method of removal. The use of an incorrect method to remove a PEG tube may result in significant morbidity to the patient. We report a case of bowel obstruction resulting from the incorrect removal of a PEG tube that required laparotomy. To prevent similar complications, PEG tubes should be removed using the appropriate method by individuals familiar with the device.

Asunto(s)

RESUMEN

Experimental endotoxemia causes hypotension and a reduction in regional blood flow, including hepatic blood flow. Complement depletion prior to endotoxemia is known to attenuate these perfusion deficits. We depleted complement with cobra venom factor prior to the administration of Escherichia coli lipopolysaccharide in Sprague-Dawley rats and studied the effects of this treatment on systemic hemodynamics, regional hepatic perfusion, and hepatocellular integrity. Complement-depleted endotoxemic rats were compared with untreated rats, rats with complement depletion alone, and rats with endotoxemia alone. Systemic hemodynamics (cardiac index, mean arterial pressure), regional hepatic perfusion (effective hepatic blood flow), and hepatocellular integrity (adenosine triphosphate [ATP], lipid peroxidation) were determined 4-6 hr after the onset of endotoxemia. The endotoxemic animals exhibited a significant decrease in systemic hemodynamic performance and regional perfusion. Complement depletion prior to endotoxemia resulted in preservation of normal systemic and hepatic perfusion. ATP and lipid peroxide levels were significantly abnormal in both groups of endotoxemic animals. Complement depletion alone did not significantly affect any of the variables studied. The maintenance of systemic and regional perfusion during endotoxemia was not cytoprotective implicating direct cellular injury independent of perfusion deficits in the pathogenesis of hepatic failure during endotoxemia.

Asunto(s)

RESUMEN

To investigate the efficacy of diagnostic laparoscopy (DL) as an adjunct in patient selection for conservative management of solid organ injuries (SOI) following blunt abdominal trauma, 15 patients with injuries documented by computed tomographic (CT) scanning were prospectively evaluated. Diagnostic laparoscopy was performed in an attempt to characterize SOI, to evaluate the abdomen for associated occult injuries, and to select patients for conservative management or laparotomy. The 15 patients had CT evidence of 17 SOIs (nine spleen, eight liver), and DL allowed adequate visualization of 15 of the 17 injuries. Occult hollow viscus injury was discovered in 2 of 15 patients (one colon, one small bowel) and required laparotomy. In the remaining 13 patients, DL revealed ongoing hemorrhage in four patients and poor visualization in one patient that prompted laparotomy (four splenorrhaphy, one hepatorrhaphy). Conservative management was employed in the treatment of eight patients with findings of minor injury or adequate hemostasis on DL. The average transfusion requirement in this group was 1.8 U. No patient failed conservative management. There were no complications attributable to DL. These data demonstrate that DL may become an effective adjunct in patient selection for conservative management of SOI following blunt abdominal trauma.

Asunto(s)

RESUMEN

Cavernous hemangiomas are the most common benign tumor of the liver. A patient presented several hours after sustaining blunt trauma to the abdomen. A CT scan of the abdomen demonstrated blood in the peritoneal space and several cavernous hemangiomas of the liver. Laparoscopy confirmed the liver lesions as the source of bleeding, although there was no active blood loss. All intraabdominal blood was aspirated and the patient made an uneventful recovery without further blood loss. Laparoscopy allowed inspection of the abdomen which revealed cessation of intraabdominal hemorrhage from the cavernous hemangiomas. He made a successful recovery without further testing or operative intervention.

Asunto(s)

RESUMEN

A powerful, time sharing and automatized method of a comprehensive data analysis for isolated, perfused guinea-pig heart studies is described. Data are collected using DataEase PC software (version 4.2) into forms with data fields specified for vital parameters consistently recorded in isolated, perfused heart studies (HR, CBF, PEAKPRESSURE, DPDT, MVO2). After running, DataEase reports the data and information is uploaded to an IBM 3081D mainframe computer on each day of heart experiment and data collection. The uploading process, the data archival and the statistical analyses are automatized by Procomm Plus commands written in Aspect Source Program (.ASP) Files for logging, data transforming and file management procedures. The ASPCOMP.EXE compiler compiles these .ASP files into Aspect Script eXecutable (.ASX) programs, which run on the PC in our laboratory and activate WYLBUR (IBM 3081D Batch-job service and Command file processor) edited files in the mainframe's electronic devices then upload, backup and save data into these files. SAS EXE files containing program instructions for the data analyzing system are then forced by Procomm Plus to operate over the data just uploaded. SAS reads the DATA files by its INFILE facility and performs comprehensive statistical analyses and produces hard output including graphics and JOB reports of dose-response- and logaritmic scale curves for delivery to team members. This computerized and automatized method developed for isolated, perfused guinea-pig heart studies is capable of performing multiple file transfer, sophisticated statistical analyses and graphic procedures after one keystroke on the PC (Alt-F5 in Procomm Plus section) and also facilitates a consistent and convenient method for planning, controlling and standardizing experiments. The method is based on an interactive computer conversation between the PC in the laboratory and the remote's WYLBUR editor. No human presence is needed; however, in case of failure, Procomm Plus gives one of the team members supervising the system a phone call in order to get human help.

Asunto(s)

RESUMEN

Small bowel perforation after blunt trauma is frequently associated with other intra-abdominal injuries. Typically, large luminal defects are encountered after blunt trauma that cannot be closed primarily without subsequent luminal compromise, necessitating formal resection with primary anastomosis. We describe a safe, rapid, and effective method by which traumatic small bowel perforations may be closed without resection using readily available gastrointestinal stapling devices. The speed of the closure allows for expedient management of associated injuries without fear of continued enteric spillage. No mesenteric resection or closure is needed, obviating the possibility of internal hernias.

Asunto(s)

RESUMEN

A powerful method of processing MEDLINE and CINAHL source data uploaded to the IBM 3090 mainframe computer through an IBM/PC is described. Data are first downloaded from the CD-ROM's PC devices to floppy disks. These disks then are uploaded to the mainframe computer through an IBM/PC equipped with WordPerfect text editor and computer network connection (SONNGATE). Before downloading, keywords specifying the information to be accessed are typed at the FIND prompt of the CD-ROM station. The resulting abstracts are downloaded into a file called DOWNLOAD.DOC. The floppy disks containing the information are simply carried to an IBM/PC which has a terminal emulation (TELNET) connection to the university-wide computer network (SONNET) at the Ohio State University Academic Computing Services (OSU ACS). The WordPerfect (5.1) processes and saves the text into DOS format. Using the File Transfer Protocol (FTP, 130,000 bytes/s) of SONNET, the entire text containing the information obtained through the MEDLINE and CINAHL search is transferred to the remote mainframe computer for further processing. At this point, abstracts in the specified area are ready for immediate access and multiple retrieval by any PC having network switch or dial-in connection after the USER ID, PASSWORD and ACCOUNT NUMBER are specified by the user. The system provides the user an on-line, very powerful and quick method of searching for words specifying: diseases, agents, experimental methods, animals, authors, and journals in the research area downloaded. The user can also copy the TItles, AUthors and SOurce with optional parts of abstracts into papers under edition. This arrangement serves the special demands of a research laboratory by handling MEDLINE and CINAHL source data resulting after a search is performed with keywords specified for ongoing projects. Since the Ohio State University has a centrally founded mainframe system, the data upload, storage and mainframe operations are free.

Asunto(s)

RESUMEN

Hepatocellular dysfunction, as a result of sepsis or endotoxemia, plays a critical role in the pathogenesis of multiple systems organ failure. Conventional methods to assay hepatic ATP require large tissue samples, making repeat measurements in the same animal impossible, and are unable to detect the minimal changes in metabolism consistent with early or reversible cellular injury. 31P NMR is a modality available for the in vivo measurement of high energy phosphates. Inorganic phosphate (Pi) and phosphomonoester (PME) ratios (markers of cellular metabolism and viability) as well as fractionated ATP may be repeatedly quantitated. To assess the early effects of endotoxemia on hepatic function, phosphorus spectra of the liver were obtained using a 1.7-cm surface coil in six rats after the ip administration of 4 mg/kg Escherichia coli lipopolysaccharide. Conventional assay was performed on 24 matched controls. Pi, PME, alpha-, beta-, and gamma-ATP peaks (expressed as percentage total signal area) were collected over 20 min, integrated, and analyzed. Pi/beta-ATP decreased over time until 6 hr reflecting ongoing uptake of inorganic phosphate and continued cellular metabolism. PME/beta-ATP ratios, which indicate cellular viability, became significantly elevated at 6 hr. Using 31P NMR, beta-ATP best reflected the early subtle energy changes present prior to cell death and subsequent organ failure with significant decreases at 2, 4, and 6 hr. Conventional assay for ATP confirmed similar trends. We conclude that 31P NMR is a valuable tool for the study of reversible hepatic energy changes during early endotoxemia.

Asunto(s)

RESUMEN

Recent reports have demonstrated a decreased incidence of pulmonary complications in patients who have undergone trauma after early operative fixation of long bone fractures. Few studies, however, have specifically examined the effect of associated long bone fractures and their management on pulmonary dysfunction in multiply injured patients with significant blunt chest trauma. We retrospectively reviewed 130 consecutive patients with major blunt chest injury as a component of multisystem trauma. Patients were assessed for overall injury severity and degree of pulmonary dysfunction after being categorized according to associated injury pattern (presence or absence of long bone fracture[s]) and treatment received (early operative fixation at less than 48 hours versus late fixation or nonoperative management). Patients with long bone fractures and concurrent blunt chest trauma had a higher incidence of pulmonary morbidity and death (p less than 0.05) than had patients with similar Injury Severity Scores without long bone fractures. Early operative fixation did not protect against pulmonary dysfunction or death in this group of patients. Despite early operative fixation, long bone fractures predispose patients with concurrent major blunt chest injury to increased pulmonary dysfunction.

Asunto(s)

RESUMEN

Percutaneous endoscopic gastrostomy (PEG) is a relatively new procedure, the indications for which are evolving. We have recently attempted PEG placement in 19 patients during the early postlaparotomy period (less than 14 days) for initiating enteral feedings or providing decompression of the gastrointestinal tract. All patients had unexpected postoperative complications, including neurologic catastrophe, recurrent obstruction of the small intestine, acute respiratory failure, enterocutaneous fistula or poor oral intake. Of 19 attempts, PEG placement was successful in 18 patients (94.7 per cent). There were no major complications; two minor complications (exit site infection) were associated with catheter placement. All PEG placed for enteral feedings were successfully used for nutritional support, and gastrointestinal decompression was accomplished in seven of eight patients requiring PEG. The results of this study demonstrate that PEG is technically feasible, safe and effective in the early postlaparotomy period in high-risk patients with complicated postoperative courses and the need for long term enteral access.

Asunto(s)

RESUMEN

OBJECTIVE: To evaluate the use of the selective alpha 1-adrenergic receptor agonist phenylephrine in the hemodynamic support of patients with septic shock. DESIGN: Retrospective analysis of clinical use of phenylephrine. SETTING: Surgical ICU in a university hospital. PATIENTS: Thirteen patients with septic shock (diagnosed by defined criteria) requiring pharmacologic support for the treatment of hypotension. INTERVENTIONS AND MAIN RESULTS: All patients underwent invasive hemodynamic monitoring followed by volume resuscitation and inotropic support to reverse flow-dependent oxygen consumption and lactic acidosis. Patients with persistent hypotension (mean arterial pressure [MAP] less than 65 mm Hg) and vasodilation (systemic vascular resistance index [SVRI] less than 1500 dyne.sec/cm5.m2 received phenylephrine at iv infusion rates of 0.5 to 9 micrograms/kg.min to maintain MAP greater than 70 mm Hg. MAP, SVRI, left ventricular stroke work index, and stroke volume index were significantly (p less than .05) increased after phenylephrine administration and at the time of highest oxygen consumption (VO2). Cardiac index was unchanged initially but increased at the time of highest VO2 (p less than .05). Pulmonary artery occlusion pressure and heart rate were unchanged. Average baseline VO2 increased from 145 to 200 mL/min.m2 and oxygen delivery (DO2) increased from 447 to 597 mL/min.m2 during phenylephrine treatment (p less than .05). Blood lactate concentrations decreased and urine output increased significantly (p less than .05), while serum creatinine concentrations remained unchanged during phenylephrine therapy. CONCLUSIONS: Treatment with phenylephrine was associated with beneficial hemodynamic effects when used to maintain perfusion, while increasing DO2 and VO2 in patients with septic shock.

Asunto(s)

RESUMEN

BACKGROUND: More than half of the subjects in the MRFIT smoked at baseline and 10% of the subjects stopped smoking permanently during the first year of the trial. In this report, rates of decline in forced expiratory volume in 1 sec (FEV1) are compared for early permanent quitters and smokers who continued to smoke throughout the trial. METHODS: Since pulmonary function testing was not standardized across all centers until the third annual visit cycle, change in FEV1 is examined over the latter half of the trial; the level of FEV1 is analyzed cross-sectionally at the midpoint of the trial. Analyses are limited to 4,926 subjects who never used beta-blockers or smoked cigars, cigarillos, or pipes during the trial and who had annual FEV1s measured over 2-4 years in the latter half of the trial. RESULTS: Quitters during the first 12 months experienced smaller declines in FEV1 over the latter half of the trial than continuing smokers, with -50.7 ml/year versus -59.0 ml/year, respectively, adjusted for the level of FEV1 (P = 0.05). Cross-sectionally, those who had never smoked, former smokers, quitters, and continuing smokers showed a gradient of decreasing FEV1, and all four smoking groups were significantly different from each other (P less than 0.05). CONCLUSIONS: These data suggest that if a middle-aged, healthy smoker stopped smoking permanently, he could expect his FEV1 to deteriorate at a more gradual rate 3-4 years after stopping smoking than a similar smoker who continued to smoke. No information was available for the complete MRFIT cohort on the pulmonary function effects immediately following smoking cessation.

Asunto(s)

RESUMEN

Hypothermia is a major problem in patients who have sustained trauma. We reviewed the cases of 100 consecutive trauma patients transferred directly to the operating room (OR) from the Emergency Department (ED) in a Level I trauma center; 26 cases could not be evaluated. Forty-two patients (57%) became hypothermic at some time between injury and leaving the OR. Fifty-five patients (74%) had a temperature (T) recorded on arrival to the ED; but only 7 (12%) were hypothermic (34.7 degrees +/- 1.5 degrees C). In contrast, 34 patients (46%) arrived in the OR hypothermic (34.8 degrees +/- 0.9 degrees C) and 26 (76%) of these left the OR hypothermic (34.8 degrees +/- 0.9 degrees C). Eight additional patients (20%) arriving in the OR with a T greater than 35.9 degrees C left the OR hypothermic (35.1 degrees +/- 0.4 degrees C). The mean T loss in the ED was significantly greater than that lost in the OR (-0.8 degrees +/- 0.7 degrees C vs. 0.0 degrees +/- 0.6 degrees C; p less than 0.0001, ANOVA). Ninety-two percent of the patients lost temperature in the ED, while 43% of the patients gained temperature in the OR. Hypothermia was associated with lower Trauma Scores, and those patients who were severely hypothermic received more intravenous fluids. However, the impact of fluid infusion was not independent from Trauma Score and did not fully explain the magnitude of the heat loss. These data suggest that hypothermia in trauma patients has a multifactoral etiology related to the magnitude of injury and that the major T loss occurs in the ED rather than in the OR.(ABSTRACT TRUNCATED AT 250 WORDS)

Asunto(s)

RESUMEN

Pulmonary function is known to be related inversely to incidence of coronary heart disease, congestive heart failure, chronic obstructive lung disease, lung cancer, and death from all causes. Reasons for some of these associations are poorly understood. Relationships between cardiovascular disease risk factors and pulmonary function were examined in 5,115 18- to 30-year-old black and white male and female participants in the study of Coronary Artery Risk Development in Young Adults (CARDIA). Forced expiratory volume in 1 s adjusted for height (FEV1/Ht2) was significantly lower in smokers than nonsmokers and in persons who reported shortness of breath; FEV1/Ht2 was correlated positively with a history of strenuous physical activity, duration of exercise on the treadmill, and high-density lipoprotein cholesterol. It was associated negatively with skinfold thicknesses, serum triglycerides, fasting serum insulin, and the Cook Medley scale of hostility. The association between pulmonary function and heart disease risk may reflect associations with physical fitness, vigor, fatness, and lipid profiles, as well as with cigarette smoking.

Asunto(s)

Asunto(s)

RESUMEN

A 75-year-old man with hyperdynamic septic shock and vasodilation was successfully supported hemodynamically for 88.5 hours through the use of a continuous infusion of phenylephrine at dosages up to 360 micrograms/min. The only other vasoactive compound administered was dopamine at a dosage of 3.4 micrograms/kg/min. Hemodynamic evaluation indicated improvements in mean arterial pressure, cardiac output, and oxygen transport parameters during the period of hemodynamic support, which did not indicate a detrimental effect on perfusion of vital organs and tissues despite the use of this vasoconstrictor. Phenylephrine's pharmacologic properties may represent an advantage for its use as a vasoconstrictor over catecholamines such as norepinephrine and dopamine, particularly in patients who develop tachyarrhythmias with these agents. The pharmacology, dosage, and appropriate monitoring of therapy with phenylephrine in patients with septic shock are discussed.

Asunto(s)

RESUMEN

We investigated a cluster of five deaths of adolescents from asthma in St. Louis during a 3-month period in 1987. Although the cluster represented a statistically significant increase in the number of asthma deaths in this age group over that observed in previous years, no common exposure to environmental, infectious, or therapeutic agents could be identified. The patterns of hospital admissions for asthma and emergency room visits at the two pediatric hospitals in the community did not suggest an increase in the frequency or severity of asthma during this time. Despite the lack of evidence for common exposure, the decedents shared many personal and medical characteristics. All decedents were black patients and were of lower socioeconomic status. All were adolescents and were responsible for regulating their own medication schedules. Lack of appreciation of the severity of their asthma by medical personnel and the patients' families was evident. For example, two patients with severe asthma had not been prescribed inhaled corticosteroids. In addition, the four decedents tested had markedly subtherapeutic or zero serum theophylline levels measured at the time of the fatal episode, even though appropriate amounts of theophylline had been prescribed. Their theophylline levels were substantially lower than levels in patients of the same age observed at the emergency room or hospitalized for asthma during the same time period. Continued efforts to educate adolescent patients, their families, and medical care providers about the treatment of asthma are warranted.

Asunto(s)