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PubMed2000

Comparison of two methods for the detection of urinary iodine used in epidemiological studies.

Two methods for the determination of iodine in urine or serum based on the Sandell-Kolthoff reaction were compared. The first was an autoanalyser method (AAII, Technicon) where the mineralisation takes place in a continuous flow manner. This procedure was used at the Department of Clinical Chemistry of the University Hospital of Berne (Switzerland) from 1968 until 1993. The second method was evaluated and adapted in our own laboratory. Each sample and the iodate-standards are mineralised in a Pyrex glass tube and the decolorisation reaction takes place in a 96-well-microtiter plate which was read by a PC-controlled photometer at 405 nm. This method, with a detection limit of 0.1 micromol/l showed good analytical recovery (90 to 110%) and a low imprecision (intra-assay coefficient of variation (CV) of 5% and an inter-assay CV of 7.5%). In contrast to the autoanalyser method, the microtiter plate-method is suitable both for series up to 24 samples (3-fold) and for single samples. A comparison of 87 samples in the range of 0.1 to 60 micromol/l which were measured with both Sandell-Kolthoff based methods showed no obvious discrepancy. These two methods showed a good agreement for the determination of urinary iodine. This guarantees that the results of earlier epidemiological studies can be compared with recent studies performed in our and many other laboratories.

Humans↗
PubMed2003

High-throughput liquid chromatography-tandem mass spectrometric analysis of sirolimus in whole blood.

Sirolimus appears as a new potent immunosuppressive agent taking advantage of therapeutic drug monitoring to optimize its use in organ transplantation. In the absence of any available commercial immunoassay it was mandatory to develop chromatographic assays. Some methods have already been proposed to quantify sirolimus in whole blood, based either on HPLC-UV, liquid chromatography-mass spectrometry (LC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). We have developed a new faster and simpler LC-MS/MS method to quantify sirolimus in blood using ascomycin as an internal standard and multiple reaction monitoring (MRM) acquisition mode. This method displays a limit of detection of 0.3 microg/l, and the intra-assay reproducibility ranges from 4.1-7.9%. The pre-analytical preparation steps are quite similar to those required for semi-automated immunoassays. Ascomycin and sirolimus present retention times of 0.89 and 0.93 min, respectively, and the turnaround time for a result (2.5 min) is also similar to that observed using a clinical analyzer. The comparison performed between HPLC-UV and LC-MS/MS displays good correlation (r = 0.949). The LC-MS/MS method described above has been used routinely for more than 2000 patient blood specimens and may present several advantages over existing methods, e.g., specificity with sufficient sensitivity, rapidity, and small blood sampling (10 microl), making it particularly adapted for routine clinical use.

Chromatography, Liquid↗
PubMed1998

Biological, psychological and environmental predictors of the alcoholism risk: a longitudinal study.

OBJECTIVE: This article reviews results from an ongoing prospective study of 453 sons of alcoholics and controls, and presents new data from the 15-year follow-up. METHOD: Drinking, but not alcohol dependent, 20-year-old sons of alcoholics and controls were evaluated for their level of response (LR) to alcohol and were subsequently followed, through personal interviews, 10 years and 15 years later. RESULTS: The 10-year follow-up of 450 (99.3%) men and provisional analyses from the first 127 subjects at 15 years revealed that a low LR at about age 20 predicted subsequent alcoholism, even after considering the original quantity and frequency of drinking and six additional domains of influence. Regarding the latter, behavioral undercontrol and work stress appear to interact with LR, with alcohol expectancies, coping mechanisms and aspects of the drinking in the environment also appearing to add to the model, while other aspects of life stress and the social support network do not. CONCLUSIONS: The prospective evaluation of subjects at higher risk for alcoholism is a potentially powerful tool in identifying the relationships among a broad range of moderators and mediators of the alcoholism risk. The present tentative results based on the first 127 subjects are primarily heuristic as findings might change in the full sample. These data set the stage for completion of the 15-year follow-up and for a subsequent 20-year evaluation which will focus on the same domains in the projected almost 560 sons and daughters of the original sample.

Adaptation, Psychological↗
PubMed2005

Photo-identification, site fidelity, and movement of female gray seals (Halichoerus grypus) between haul-outs in the Baltic Sea.

The growing gray seal population in the Baltic Sea has led to increased conflicts with fisheries. Despite limited data on gray seal ecology, management measures, such as culling, have been implemented recently. We studied movements and site fidelity of Baltic gray seals using mark-recapture analysis based on photographic identification of individuals (photo-id). Seals were photographed at the major summer haul-out sites. Profile photographs of the head and neck were matched using purpose-written software to generate a database of capture histories from 1995-2000. The haul-outs were grouped into seven areas. Darroch's method (20) for a two-sample capture-recapture census was adapted to estimate rates of movement between the areas. The majority of seals were estimated to remain within the same area, suggesting that Baltic gray seals exhibit a high degree of site fidelity during the summer, and that fidelity to a site lasts for more than one season.

Animals↗
PubMedDate not supplied

Types of psychological reactions in patients with lower-extremity amputations.

The aim of this study was to establish types of psychological reactions and conditions in patients with lower-extremity amputations. Apart from using psychological interviews, detection was performed using psychometric tests: Minnesota Multiphasic Personality Inventory and Beck Depression Inventory. Psychometric parameters were analyzed in a group of 20 examinees treated at the Medical Rehabilitation Clinic in Novi Sad. Out of the whole sample, 45% of patients presented with adaptive reactions to amputation and consequent disability, whereas 55% presented with maladaptive responses. The registered psychopathological symptoms included nosologic categories: reaction to stressful events and adjustment disorder (predominantly affecting other emotions; mixed disorder of conduct and emotions; prolonged depressive reaction) and dysthymia. When working with lower-extremity amputees, apart from adaptive, nonpathological forms of behavior, one also encounters maladaptive responses with predomination of mood disorders due to severe somatic stress.

Adaptation, Psychological↗
PubMed1999

Capillary whole blood measurement of islet autoantibodies.

OBJECTIVE: Islet cell antibody (ICA) measurements in serum are used for large-scale screening to identify subjects who are at high risk of developing type 1 diabetes. The aim of this study was to adapt measurements to capillary whole blood samples to facilitate and reduce screening costs. RESEARCH DESIGN AND METHODS: GAD65, IA-2, and combined GAD65/IA-2 antibody tests were performed on patients with type 1 diabetes, first-degree relatives of patients, and control subjects, and results from serum, plasma, whole venous blood, and capillary whole blood lysates were compared. Measurements obtained in serum and eluates from dried capillary blood spots from 36 ICA+ first-degree relatives were also compared. RESULTS: GAD65, IA-2, and combined GAD65/IA-2 antibody levels were completely concordant with measurements obtained from serum, plasma, whole venous blood, and capillary whole blood lysates. Antibody levels obtained in eluates from dried capillary blood spots were lower than corresponding serum samples, and weak antibodies were not detected. CONCLUSIONS: Initial screening for diabetes risk can be performed using one drop of capillary whole blood without further processing to separate serum. This method should be considered as a way to simplify and reduce costs of screening programs.

Autoantibodies↗
PubMed2002

Work experiences and psychological well-being of former hospital-based nurses now employed elsewhere.

Hospitals in Ontario have undergone significant restructuring and downsizing during the past few years. Such changes have created negative reactions among both those who survive the downsizing and those who lose their jobs involuntarily. This study compared work satisfactions and indicators of psychological well-being of 36 nurses during these changes and three years later when they were employed elsewhere. Job satisfaction and psychological well-being increased while psychological burnout decreased in this sample.

Adaptation, Psychological↗
PubMed2001

Supplemental soybean oil or corn for beef heifers grazing summer pasture: effects on forage intake, ruminal fermentation, and site and extent of digestion.

Nine Angus x Gelbvieh heifers (average BW = 347 +/- 2.8 kg) with ruminal and duodenal cannulas were used in a split-plot designed experiment to determine the effects of soybean oil or corn supplementation on intake, OM, NDF, and N digestibility. Beginning June 8, 1998, heifers continually grazed a 6.5-ha predominantly bromegrass pasture and received one of three treatments: no supplementation (Control); daily supplementation of cracked corn (Corn) at 0.345% of BW; or daily supplementation (0.3% of BW) of a supplement containing cracked corn, corn gluten meal, and soybean oil (12.5% of supplemental DM; Oil). Soybean oil replaced corn on a TDN basis and corn gluten meal was included to provide equal quantities of supplemental TDN and N. Three 23-d periods consisted of 14 d of adaptation followed by 9 d of sample collections. Treatment and sampling period effects were evaluated using orthogonal contrasts. Other than crude fat being greater (P = 0.01) for supplemented heifers, chemical and nutrient composition of masticate samples collected via ruminal evacuation did not differ (P = 0.23 to 0.56) among treatments. Masticate NDF and ADF increased quadratically (P < or = 0.003) and N decreased linearly (P = 0.0001) as the grazing season progressed. Supplementation did not influence (P = 0.37 to 0.83) forage OM intake, total and lower tract OM digestibility, ruminal and total tract NDF digestibility, or total ruminal VFA; however, supplemented heifers had lower ruminal molar proportions of acetate (P = 0.01), higher ruminal molar proportions of butyrate (P = 0.007), and greater quantities of OM digested in the rumen (P = 0.10) and total tract (P = 0.02). As the grazing season progressed, total tract OM and N and ruminal NH3 concentrations and NDF digestibility decreased quadratically (P < or = 0.04). Microbial N flow (P = 0.09) and efficiency (P = 0.04) and postruminal N disappearance (P = 0.02) were greater for Control heifers and declined linearly (P < or = 0.02) as the grazing season advanced. Depressed microbial N flow seemed to be more pronounced for Oil than for the Corn treatment. Although total digestible OM intake increased with supplementation, metabolizable protein supply was reduced in supplemented heifers. Therefore, feeding low levels of supplemental grain with or without soybean oil is an effective strategy to increase dietary energy for cattle grazing high-quality forages, but consideration should be given to reduced supply of metabolizable protein.

Animal Feed↗
PubMed2002

Effects of oscillating dietary protein on ruminal fermentation and site and extent of nutrient digestion in sheep.

Eight cannulated wethers (BW = 52.5 +/- 5.7 kg) were used in a replicated 4 x 4 Latin square designed experiment to evaluate the effects of oscillating dietary protein concentrations on ruminal fermentation, site and extent of digestion, and serum metabolite concentrations. Four treatments consisted of a 13, 15, or 17% CP diet fed daily or a regimen in which dietary CP was oscillated between 13 and 17% on a 48-h basis (ACP). All diets consisted of 65% bromegrass hay (10.5% CP, 61.9% NDF, 37.2% ADF) plus 35% corn-based supplement and were formulated to contain the same amount of degradable intake protein (9.6% of DM) plus additional undegradable intake protein (SoyPLUS, West Central Cooperative, Ralston, IA) to accomplish CP levels above 13%. Each of four experimental periods were 16 d in duration with 12 d for diet adaptation followed by 4 d for sample collection. All wethers were fed at 3.0% of initial BW (DM basis) throughout the experiment, resulting in an average organic matter intake of 1.39 kg/d across treatments. When compared to the 15% CP daily treatment, feeding ACP had no effect (P > or = 0.10) on ruminal or lower tract N, NDF, ADF, or OM digestion. True ruminal OM digestion responded quadratically (P = 0.07) to increasing dietary CP, reaching a maximum of 52.0% of OM intake with the 15% CP treatment. Sheep fed ACP tended to have lower (P = 0.08) ruminal NH3 N concentrations and an overall higher (P = 0.0001) molar proportion of acetate compared to those fed 15% CP daily. Total VFA concentrations were not affected (P > or = 0.45) by increasing dietary CP. Microbial efficiency did not differ (P > or = 0.55); thus, bacterial N flow at the duodenum responded quadratically (P = 0.04) to increasing dietary CP. Nonbacterial N (P = 0.001) and total N (P = 0.01) flows at the duodenum and total tract N digestibility (P < or = 0.04) increased linearly as dietary CP increased. Wethers fed ACP maintained a lower (P = 0.002) serum glucose and lower (P = 0.0006) serum urea N compared to those fed 15% CP daily. Because the CP content of the diet was increased at the expense of corn, the response to increased CP observed in this experiment is most likely due to negative associative effects of supplemental starch on ruminal fermentation and microbial growth. Oscillating the CP content of the diet on a 48-h basis has little effect on digestion or N utilization in sheep compared with feeding the same quantity of protein on a daily basis.

Animal Feed↗
PubMed2005

Effect of restricted forage intake on ruminal disappearance of bromegrass hay and a blood meal, feather meal, and fish meal supplement.

Two experiments were conducted to determine in situ disappearance of bromegrass hay and a ruminally undegraded protein (RUP) supplement in beef cattle fed restricted amounts of forage. Six Angus crossbred cattle (BW = 589 +/- 44.4 kg; three steers and three heifers) fitted with ruminal cannulas were fed chopped (2.54 cm) bromegrass hay (8.9% CP) at one of three percentages of maintenance intake (30, 55, or 80%; one steer and one heifer per treatment). In both experiments, the cattle were allowed 7 d for diet adaptation followed by 3 d of sample collection. In Exp 1, in situ bags (50 microm pore size) containing 4.1 g of brome-grass hay (OM basis) were inserted into the rumen and subsequently removed at 3, 6, 9, 12, 15, 18, 24, 36, and 48 h after insertion. Nonlinear regression models were used to determine the rapidly solubilized protein Fraction A, the potentially ruminal degradable protein Fraction B, the ruminally undegraded protein Fraction C, and protein degradation rate. Intake level did not affect (P = 0.15 to 0.95) forage protein remaining after in situ incubation or Fractions A, B, and C; however, effective ruminal degradation of hay protein tended to increase quadratically (P = 0.12) as forage intake increased. In Exp 2, 4.2 g (OM basis) of an RUP supplement (6.8% porcine blood meal, 24.5% hydrolyzed feather meal, and 68.7% menhaden fish meal) formulated to provide equal amounts of metabolizable protein across all levels of hay consumption was evaluated in a similar manner as in Exp 1. The undegraded protein fraction of the supplement did not differ (P = 0.16 to 0.74) across treatments at 3, 6, 9, and 18 h; however, increasing forage intake resulted in a linear increase (P < or = 0.06) in undegraded protein remaining at 12, 15, 24, 36, and 48 h. Dietary treatment had no affect (P = 0.30) on protein Fractions A, B, or C; however, protein degradation rate of the supplement decreased linearly (P = 0.03) as forage intake increased. Therefore, effective ruminal degradation of the supplement decreased linearly (P = 0.01) from 50.8 to 40.9% as forage intake increased from 30 to 80% of maintenance. Corresponding estimates of supplement RUP were 49.2, 56.5, and 59.1% for the 30, 55, and 80% of maintenance intake treatments, respectively. Restricting dietary intake can decrease the quantity of dietary protein that escapes ruminal degradation. Tabular estimates of RUP may not be appropriate for formulating diets to balance metabolizable protein in beef cattle consuming limited quantities of forage.

Animal Feed↗
PubMed2006

Influence of soybean hull supplementation on rumen fermentation and digestibility in steers consuming freshly clipped, endophyte-infected tall fescue.

Six steers (288.6 +/- 2.1 kg of BW) fitted with rumen and duodenal cannulas were used in a crossover design to evaluate intake, rumen fermentation, and site of nutrient digestion of freshly clipped, endophyte-infected (E+) Kentucky 31 tall fescue with or without soybean hull (SH) supplementation at 0.60% of BW (OM basis). Steers were placed in metabolism units within an environmentally controlled room and provided with free-choice access to fresh forage, water, and a vitamin/mineral supplement. The spring growth of E+ tall fescue was harvested daily during the experiment. Supplement was fed at 0700 with approximately 65% of the estimated daily forage. To maintain a fresh forage supply, additional forage was stored in a cooler and fed at 1900. Periods were 21 d with 14 d of adaptation and 7 d of digesta sample collection. Chromic oxide was used as a marker of duodenal digesta flow. Duodenal samples were taken 4 times daily with times shifting by 1 h each day to represent all 24 h of a day. Treatments were considered significant at P < 0.05. Supplementation of SH decreased forage OM intake from 1.64 to 1.41% of BW but increased total OM intake from 1.64 to 2.01% of BW. Apparent percentages (53.1%) and quantities (2,786 g/d) of rumen OM disappearance were not affected by supplementation. Percentages of total tract OM disappearance were not different (70.8%). Percentages of apparent rumen NDF disappearance also were not different (65.6%). Percentages of N disappearance were not different. Supplementation of SH resulted in increased total N (34.1 g/d) and microbial N (17.1 g/d) flowing to the duodenum. Rumen pH (6.5) was not affected, and rumen ammonia concentrations exhibited a time x treatment interaction in which SH decreased ammonia for 12 h after supplementation. Total VFA concentrations (103.9 mM) were unaffected. Liquid dilution rate (12.7%/h) and rumen OM fill (4.3 kg) were not different between treatments. Supplementation of SH at a rate of 0.60% of BW (OM basis) to calves consuming fresh E+ tall fescue decreased forage consumption but resulted in greater total intake, greater flow of N to the duodenum, and increased total tract OM disappearance.

Ammonia↗
PubMed1982

Effect of diet on amino and nucleic acids of rumen bacteria and protozoa.

Amino acid composition and nucleic acid content of pure cultures of rumen bacteria (17 species) were analyzed. Amino acid composition between gram-positive and -negative organisms was not different. The total nitrogen content of gram-negative bacteria (10.8%) was significantly higher than gram-positive organisms (9.9%). Deoxyribonucleic acid-nitrogen: total nitrogen (mg/g) differed between gram-positive (8.8) and gram-negative (18.9) bacteria, but there was no significant difference in ratio of ribonucleic acid-nitrogen to total nitrogen. In a second experiment six rumen-fistulated cattle were fed either a high roughage (85% alfalfa hay plus 15% concentrate) or high concentrate diet (15% alfalfa hay and 85% concentrate). Cattle were adapted 14 days and rumen contents sampled on 3 consecutive days. Nitrogen content was higher in protozoa from cattle fed low concentrate (8.4%) than in protozoa from cattle fed high concentrate (7.9%) but was similar in bacteria for both diets. Deoxyribonucleic acid nitrogen: total nitrogen (mg/g in bacteria decreased from 27.2 in cattle fed the low concentrate diet to 20.9 in those fed the high concentrate diet. Differences between sampling days were significant for both bacteria and protozoa for ratio of deoxyribonucleic acid-nitrogen to total nitrogen but were significant only in protozoa for ratio of ribonucleic acid nitrogen to total nitrogen. Ribonucleic acid may serve as a marker for estimating microbial production in the rumen if sources of variation are recognized and corrected adequately.

Amino Acids↗
PubMed1994

Hydroxyapatite coatings.

A series of investigations over the past several years has evaluated a number of implant materials with and without plasma-sprayed hydroxyapatite (HA) coatings for use in load-bearing implant applications. HA-coated implants have exhibited greater interface shear attachment characteristics when compared to uncoated implants; these results have been demonstrated with dense (flat), porous-coated, and macrotextured implant surfaces. Maximum attachment strength also was found to occur within a shorter period of time postoperatively with the HA-coated samples, indicating a more rapid tissue adaptation to the implant surfaces. Plasma-sprayed HA coatings provide an osteophilic and osteoconductive surface that increases both the bone-implant attachment strength, as well as the rate of bone adaptation to the HA-coated implant surface.

Biomechanical Phenomena↗
PubMed2000

Hyperbaric oxygen therapy in acute necrotizing infections with a special reference to the effects on tissue gas tensions.

Clostridial gas gangrene and perineal necrotizing fasciitis or Fournier's gangrene are rare but serious infections with an acute onset, rapid progression, systemic toxemia and a high mortality rate. The aim of this study was to investigate the efficacy of surgery, antibiotic treatment, surgical intensive care and in particular the role of hyperbaric oxygen (HBO) in the management of these infections. An experimental rat model was used to investigate the possibilities for measuring tissue oxygen and carbon dioxide tensions during hyperbaric oxygen treatment. In addition to this preliminary experimental study, Silastic tube tonometer and capillary sampling techniques were tested to measure the effect of hyperbaric oxygen treatment on subcutaneous oxygen and carbon dioxide tensions in patients with necrotizing fasciitis and healthy controls. Between January 1971 and April 1997, 53 patients with Clostridial gas gangrene were treated in the Department of Surgery, University of Turku. The patients underwent surgical debridement, broad spectrum antibiotic therapy and a series of hyperbaric oxygen treatments at 2.5 atmospheres absolute pressure (ATA). Twelve patients died (22.6%). Hyperbaric oxygen therapy in gas gangrene seems to be life-, limb- and tissue saving. Early diagnosis remains essential. Patient survival can be improved if the disease is recognized early and appropriate therapy instituted promptly. Between February 1971 and September 1996, 33 patients with perineal necrotizing fasciitis were treated in the Department of Surgery, University of Turku. The management included surgical debridement of the necrotic tissue with incisions and drainage of the involved areas, antibiotic therapy, hyperbaric oxygen treatment at 2.5 ATA pressure and surgical intensive care. Three patients died giving a mortality rate of 9.1%. The survivors received hyperbaric oxygen therapy for 2-12 times. Our results indicate that hyperbaric oxygenation is an important therapeutic adjunct in the treatment of Fournier's gangrene. Electrical equipment should not be used unsheltered in a hyperbaric chamber due to the increased risk of fire. The subcutaneous tissue gas tensions of rats were therefore measured using a subcutaneously implanted Silastic tube tonometer and a capillary sampling technique. The method was successfully adapted to hyperbaric conditions. The subcutaneous oxygen tension levels increased five fold and the carbon dioxide tension levels two fold compared to initial levels. The PO2 and PCO2 of subcutaneous tissue and arterial blood were measured directly in six patients with necrotizing fasciitis and three healthy volunteers in normobaric conditions and during hyperbaric oxygen exposure at 2.5 ATA pressure. The measurements were carried out in healthy tissue and at the same time in the vicinity of the infected area of the patients. During HBO at 2.5 ATA subcutaneous oxygen tensions increased several fold from baseline values and carbon dioxide tensions also increased, but to a lesser degree in both healthy and infected tissues. When examining the subcutaneous PO2 levels measured from patients with necrotizing fasciitis, the PO2 was regularly higher in the vicinity of the infected area than in healthy tissue. In general, HBO treatment resulted in a marked increase in tissue oxygenation in both healthy tissue and in the vicinity of infected tissue. The hyper-oxygenated tissue zone surrounding the infected area may be of significance in preventing the extension of invading microorganisms.

Aged↗
PubMedDate not supplied

Fluorescent location of malignant cells in fine needle aspirates.

Malignant cells in fine needle aspirates possess a cell surface protease which can be targeted with fluorescent affinity probes. Cells with active GB exhibit cell surface fluorescence when stained with such affinity probes. The nuclei of all cells on the slides can be counterstained with a nuclear fluorescent stain. Malignant cells are then located by their cell surface fluorescence and their diagnosis confirmed by examining their fluorescent nuclei. Normal cells and benign cells exhibit no cell surface fluorescence and can be ignored. This technique can be used to rapidly select cells of cytological interest in FNA samples obtained routinely and might be adapted for automated screening of FNA.

Automation↗
PubMed2000

Hyperbaric oxygen therapy in acute necrotizing infections. With a special reference to the effects on tissue gas tensions.

Clostridial gas gangrene and perineal necrotizing fasciitis or Fournier's gangrene are rare but serious infections with an acute onset, rapid progression, systemic toxemia and a high mortality rate. The aim of this study was to investigate the efficacy of surgery, antibiotic treatment, surgical intensive care and in particular the role of hyperbaric oxygen (HBO) in the management of these infections. An experimental rat model was used to investigate the possibilities for measuring tissue oxygen and carbon dioxide tensions during hyperbaric oxygen treatment. In addition to this preliminary experimental study, Silastic tube tonometer and capillary sampling techniques were tested to measure the effect of hyperbaric oxygen treatment on subcutaneous oxygen and carbon dioxide tensions in patients with necrotizing fasciitis and healthy controls. Between January 1971 and April 1997, 53 patients with Clostridial gas gangrene were treated in the Department of Surgery, University of Turku. The patients underwent surgical debridement, broad spectrum antibiotic therapy and a series of hyperbaric oxygen treatments at 2.5 atmospheres absolute pressure (ATA). Twelve patients died (22.6%). Hyperbaric oxygen therapy in gas gangrene seems to be life-, limb- and tissue saving. Early diagnosis remains essential. Patient survival can be improved if the disease is recognized early and appropriate therapy instituted promptly. Between February 1971 and September 1996, 33 patients with perineal necrotizing fasciitis were treated in the Department of Surgery, University of Turku. The management included surgical debridement of the necrotic tissue with incisions and drainage of the involved areas, antibiotic therapy, hyperbaric oxygen treatment at 2.5 ATA pressure and surgical intensive care. Three patients died giving a mortality rate of 9.1%. The survivors received hyperbaric oxygen therapy for 2-12 times. Our results indicate that hyperbaric oxygenation is an important therapeutic adjunct in the treatment of Fournier's gangrene. Electrical equipment should not be used unsheltered in a hyperbaric chamber due to the increased risk of fire. The subcutaneous tissue gas tensions of rats were therefore measured using a subcutaneously implanted Silastic tube tonometer and a capillary sampling technique. The method was succesfully adapted to hyperbaric conditions. The subcutaneous oxygen tension levels increased five fold and the carbon dioxide tension levels two fold compared to intial levels. The PO2 and PCO2 of subcutaneous tissue and arterial blood were measured directly in six patients with necrotizing fasciitis and three healthy volunteers in normobaric conditions and during hyperbaric oxygen exposure at 2.5 ATA pressure. The measurements were carried out in healthy tissue and at the same time in the vicinity of the infected area of the patients. During HBO at 2.5 ATA subcutaneous oxygen tensions increased several fold from baseline values and carbon dioxide tensions also increased, but to a lesser degree in both healthy and infected tissues. When examining the subcutaneous PO2 levels measured from patients with necrotizing fasciitis, the PO2 was regularly higher in the vicinity of the infected area than in healthy tissue. In general, HBO treatment resulted in a marked increase in tissue oxygenation in both healthy tissue and in the vicinity of infected tissue. The hyperoxygenated tissue zone surrounding the infected area may be of significance in preventing the extension of invading microorganisms.

Acute Disease↗