Catheter Samples Research Articles

Diagnostic Value of Candida Colonization Index in The Early Diagnosis of Invasive Candidal Infection

Objective: To investigate the diagnostic value of Candida colonization index (CCI) in the early diagnosis of invasive candidal infection in medical mix (medical and surgical intensive care units (ICU). Methods: Mouth, axillae, nasogastric catheter, rectum, and urine culture samples taken from the patients admitted to the reanimation and neurological ICU for 19 months were retrospectively evaluated and CCI were calculated. Results: CCI reached ≥0,5 in the cultures of 29 patients. 29 patients developed candidal infection; 27 (27/29) of them had CCI ≥0,5. 18 patients developed urinary infections, 10 patients developed candidemia, and 1 patient developed wound infection. CCI ≥0,5 was found as the only independent predictor for invasive candidal infection (p<0,001, OR: 701,553, %95 CI; 28,310-17385,22). The positive predictive value, sensitivity, and specifity of CCI for the candidal infection were found to be 93.1% and 96.2%, respectively. Conclusions: We concluded that monitoring for CCI in patients with unknown fever, severe sepsis or septic shock in the medical ICU offers an early diagnosis and intervention to prevent invasive candidal infection. Independently from the other risk factors, CCI may be considered as an effective test for early diagnosis of invasive candidal infection in medical and surgical ICU patients.

Incretin Hormone Release Does Not Involve Hepatic Portal Vein Glucose Sensors

The incretin effect, which is defective in individuals with T2D, involves the secretion of GLP-1 and GIP when glucose is given orally, but not when it is infused via a peripheral vein. Glucose ingestion results in a hepatic portal vein/arterial glucose gradient. This activates portal vein glucose sensors which play an important role in the regulation of glucose metabolism during feeding. It is unknown whether these sensors contribute to GLP-1 or GIP secretion during glucose ingestion. To test the hypothesis that portal but not peripheral vein glucose infusion would stimulate incretin hormone secretion, intraportal (infusion) and femoral artery (sampling) catheters were placed in 6 dogs. Two weeks later the animals were administered an oral glucose tolerance test (OGTT; 0.9 g/kg) and one and two weeks after that the arterial plasma glucose profile which occurred during each OGTT was matched by infusing glucose either into the portal (Po) or a peripheral (Pe) vein. The AUCs for glucose (0-180 min; total) were nearly identical: 8251±325, 8219±334 and 8200±341 mg/dl (180 min) in the OGTT, Po and Pe treatments, respectively. The total glucose administered was reduced in the Pe (562±76 mg/kg) compared to the OGTT and Po treatments (900±0 and 856±92 mg/kg, respectively). During the 1st hour the arterial insulin and c-peptide responses were ∼25% greater in the OGTT compared to the other treatments, whereas there was &amp;lt;5% difference in their levels in Po vs. Pe. Arterial glucagon fell modestly in all treatments. Oral glucose administration increased arterial GLP-1 and GIP levels by &amp;gt;6-fold over basal, but their levels did not change in Po or Pe. The 0-180 min AUCs for GLP-1 were 669±218, 315±128 and 323±81 pg/ml, and for GIP were 14725±1506, 2556±529 and 2658±316 pg/ml in the OGTT, Po and Pe treatments, respectively. Thus, activation of portal vein glucose sensors did not stimulate the release of, or insulinotropic response to, incretin hormones in the overnight fasted dog, but portal vein glucose entry enhanced glucose clearance. Disclosure D.S. Edgerton: Speaker's Bureau; Self; Novo Nordisk A/S. G. Kraft: None. M.S. Smith: None. L. Moore: None. B. Farmer: None. H. Sara: None. M. Scott: None. M. Moore: None. M.A. Nauck: Advisory Panel; Self; AstraZeneca, Boehringer Ingelheim GmbH, Eli Lilly and Company, Fractyl Laboratories, Inc., GlaxoSmithKline plc., Berlin-Chemie AG, Merck Sharp &amp; Dohme Corp., Novo Nordisk A/S. Speaker's Bureau; Self; AstraZeneca, Boehringer Ingelheim GmbH, Eli Lilly and Company, Berlin-Chemie AG, Merck Sharp &amp; Dohme Corp., Medscape, Novo Nordisk A/S. Research Support; Self; AstraZeneca, Berlin-Chemie AG, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Novartis AG, GlaxoSmithKline plc., Novo Nordisk A/S. Consultant; Self; Nordic Bioscience, Empros. A.D. Cherrington: Advisory Panel; Self; Biocon. Consultant; Self; Boston Scientific Corporation. Research Support; Self; Boston Scientific Corporation. Consultant; Self; Eli Lilly and Company. Advisory Panel; Self; Fractyl Laboratories, Inc.. Stock/Shareholder; Self; Fractyl Laboratories, Inc.. Consultant; Self; Galvani Bioelectronics Limited. Research Support; Self; Galvani Bioelectronics Limited. Consultant; Self; MedImmune. Advisory Panel; Self; Metavention. Stock/Shareholder; Self; Metavention. Consultant; Self; Novo Nordisk Inc.. Research Support; Self; Novo Nordisk Inc.. Advisory Panel; Self; NuSirt Biopharma, Inc., Sensulin Labs, LLC.. Other Relationship; Self; Sensulin Labs, LLC.. Consultant; Self; Silver Lake. Research Support; Self; Silver Lake. Consultant; Self; Thermalin Diabetes, LLC., Thetis Pharmaceuticals LLC.. Stock/Shareholder; Self; Thetis Pharmaceuticals LLC.. Advisory Panel; Self; VTV Therapeutics. Consultant; Self; VTV Therapeutics. Advisory Panel; Self; Zafgen. Research Support; Self; Zafgen. Stock/Shareholder; Self; Zafgen. Consultant; Self; Abvance. Other Relationship; Self; Abvance. Consultant; Self; California Institute for Biomedical Research (Calibr). Advisory Panel; Self; These Three Medical, Inc (T3M).

Catheter-related candidemia and identification of causative Candida species in patients with cardiovascular disorder.

Background and Purpose:Catheter-related blood circulation infection is the most dangerous and serious side-effects of vascular catheters, which leads to the enhancement of the costs, mortality, and hospital stay duration, especially in the Intensive Care Unit. Regarding this, the aim of the current study was to identify the prevalence of catheter-induced candidemia in the Tehran Heart Center, a heart hospital in Tehran, Iran.Materials and Methods:This study was conducted on patients admitted to Tehran Heart Center for a minimum of 7 days during 18 months. To detect the fungal elements, blood culture and catheter culture were performed in the patients receiving central or peripheral venous catheter. Then, the polymerase chain reaction (PCR) was applied to determine the possible diagnosis.Results:The investigation of 223 samples led to the identification of a total of 15 (6.7%) yeast isolates obtained from 9 (60%), 4 (26.6 %), and 2 (13.4%) catheter, blood, and skin (of the catheter insertion areas) cultures, respectively. Out of nine Candida isolates obtained from the catheter samples, 1 (11.1%), 1 (11.1%), 2 (22.2%), and 5 (55.6%) cases were identified as C. tropicalis, C. membranifaciens, C. glabrata, and C. albicans, respectively, using the internal transcribed spacer region sequencing. Furthermore, the four yeasts isolated from the blood culture included C. tropicalis, C. carpophila, C. membranifaciens, and Cryptococcus albidus. Additionally, one case of C. glabrata and one case of C. albicans were isolated from the skin culture of the catheter insertion areas in patients with positive catheter culture. We reported two cases of catheter-related candidemia caused by C. membranifaciens and C. tropicalis on the basis of the genetic similarity of the species isolated from the blood and catheter. These cases were treated successfully with intravenous fluconazole and catheter removal.Conclusion: There is some evidence indicating the growing prevalence of non-albicans Candida infections. Many risk factors, including prior antibiotic therapy, use of a central venous catheter, surgery, and parenteral nutrition, are considered to be associated with candidemia in hospitalized heart failure patients. The identification of the route of infection in candidemia is difficult. In the current study, the positive blood and catheter cultures for Candida isolates and the similarity of the ITS region of ribosomal DNA sequence of Candida isolated from two patients confirmed the diagnosis of intravenous catheter-related candidemia.

A Standard Push-Pull Protocol for Waste-Free Sampling in the Pediatric Intensive Care Unit.

Blood sampling is a major source of blood loss in the pediatric intensive care unit (PICU). Blood-sparing sampling techniques such as the push-pull method can significantly reduce sampling-related blood loss and protect patients from anemia and blood transfusions. The push-pull method is supported by research evidence for central venous catheter (CVC) sampling, but research protocols differ and not all CVCs and laboratory tests have been studied. A standard push-pull protocol for the PICU was developed, implemented, and evaluated in this evidence-based practice project. Results show that the protocol can be used safely and reliably as a standard waste-free sampling method in the PICU.

A catheter friction tester using balance sensor: Combined evaluation of the effects of mechanical properties of tubing materials and surface coatings.

In this study, we introduce a new experimental approach to characterize the forces emerging from simulated catherization. This setup allows for a linear translation of urinary catheters in vertical direction as controlled by an actuator. By employing silicone-based elastomer with a duct of comparable diameter with catheters as urethra model, sliding contacts during the translation of catheters along the duct is generated. A most unique design and operation feature of this setup is that a digital balance was employed as the sensor to detect emerging forces from simulated catherization. Moreover, the possibility to give a variation in environment (ambient air vs. water), clearance, elasticity, and curvature of silicone-based urethra model allows for the detection of forces arising from diverse simulated catherization conditions. Two types of commercially available catheters varying in tubing materials and surface coatings were tested together with their respective uncoated catheter tubing. The first set of testing on the catheter samples showed that this setup can probe the combined effect from flexural strain of bulk tubing materials and slipperiness of surface coatings, both of which are expected to affect the comfort and smooth gliding in clinical catherization. We argue that this new experimental setup can provide unique and valuable information in preclinical friction testing of urinary catheters.

Vasopressin V1a Receptor of Renal Collecting Duct Intercalated Cells Mediates Urinary Acidification

Vasopressin (AVP) drives urinary concentration via V2 receptors in the distal nephron and collecting duct of the kidney. Parallel activation of V1a receptors (V1aR) has been implicated in renal acid‐base handling, but cell type‐related information on this receptor is still scarce. We hypothesized that activation of V1aR in intercalated cells (IC) contributes to acid‐base homeostasis by the kidney.We generated an anti‐V1aR antibody and verified its specificity using V1aR‐knockout tissues. For localization studies in mice, rat and human tissue, we used immunofluorescence and confocal microscopy or 3D‐structured illumination microscopy (3D‐SIM). For functional studies in vivo, V1aR‐specific agonist, AO‐4‐67, was administered in AVP‐deficient Brattleboro rats and C57/BI6J mice (0.2, 2, or 10μg/kg b.w.; 1 to 4h). Urine was collected in metabolic cages or via ureteral catheter and plasma samples were taken. Isolated, microperfused mouse collecting ducts were analyzed for V1aR‐dependent luminal pH changes and cultured inner medullary collecting duct cells for proton‐secreting vH+‐ATPase regulation.V1aR immunoreactivity of type‐A IC was demonstrated in basolateral membrane and cytoplasmic granules, whereas type B IC revealed perinuclear and subapical granular signal alone. Administration of AO‐4‐67 to Brattleboro rats for 4h resulted in increased urinary proton secretion (+34% after 1h, p&lt;0.05) and decreased bicarbonate excretion (up to −90% after 3h, p&lt;0.001). Similarly, catheterized mice showed rapid urinary acidification in response to AO‐4–67 (pH from 7.18 to 6.78 after 20 min, p&lt;0.05). Basolateral application of V1aR agonist or AVP in isolated perfused collecting ducts resulted in decreased luminal pH values (−5% after 3 min, p&lt;0.05). Cultured collecting duct cells showed significant increases in luminal vH+‐ATPase immunoreactivity upon V1aR stimulation (+90% after 4h, p&lt;0.001).In summary, our results suggest that activation of V1aR in renal type‐A intercalated cells induces proton secretion into the urine and promote urinary acidification.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

CATHETER-ASSOCIATED URINARY TRACT INFECTION IN CHILDREN WITH CONGENITAL HEART AND KIDNEY DISEASE

Aim. To detect pathogens that are capable of causing diseases or infections as postoperative complications in children with congenital heart and kidney disease, to be effective at preventing catheter-associated urinary tract infection. Materials and methods. Clinical material served samples of excrement, urine and urinary catheters of Foley (Unomedica) from sixteen children with congenital heart disease, who were being treated at the Almazov Medical Research Center. The isolated strains were classified according to the identification RapID Systems (USA). Antibiotic sensitivity of isolated bacteria was performed by thedisk diffusion method (NICF, Russia). Scanning electron microscopy (SEM) imaging revealed several types of bacterial communities on intraluminal surface of urethral catheter. Escherichia coli strains were tested for presence of virulence genes a-hemolysin: hly А, В, C by real-time PCR testing (using the detecting amplifier DTlite (DNA Technology, Russia). Results. The main microbial agents were isolated in urines samples from 3 of 16 patients were Staphylococcus aureus and E. coli. Gram-positive cocci were found in 56% samples of excrement and Gram-negative in 44% samples. It was found that on intraluminal surface in 10 out of 16 urethral catheter samples mixed microbial cultures were isolated, S. aureus and E. coli were prevailed. Methicillin-resistant strains of S. aureus (MRSA) have been reported in 85% cases. E. coli a-hemolysin (Ыу А, В, C) were identified in 60% strains. SEM examination two samples of urinary catheters revealed actinomyces-like forms of bacteria that were not detected in the primary bacteriological study. Conclusion. Early diagnosis of catheter-associated urinary tract infections in children with congenital heart heart and kidney disease requires a comprehensive approach to setting detecting priorities and selecting the most effective microbiological analysis, and is mandatory to use modem diagnostic methods.

Improved Coronary Sinus Blood Sampling for Cardiac Research

Background: Coronary sinus (CS) blood sampling is important for measuring metabolites and biomarkers in cardiovascular research, but can be technically challenging. Here we demonstrate the use of the antecubital fossa for CS blood sampling as an alternative to femoral access, and a simple technique of paired venous and CS blood gas analysis for confirmation of valid CS sampling. We also demonstrate improvement in sampling accuracy by using a coronary guide wire to stabilize the sampling catheter in the CS. Methods: Paired blood samples from CS and peripheral vein were collected from patients at the time of primary PCI for acute myocardial infarction. Venous access for CS sampling was via the antecubital vein. Blood gas analysis was used to confirm a true CS sample (pO2[CS]<pO2[v]). CS sampling was carried out with a catheter in the CS (standard technique) or with the addition of a coronary guide wire for stability (modified technique). Results: 108 patients underwent CS and peripheral venous blood sampling. The standard technique for CS sampling was used in 62 patients and the modified technique in 46 patients. Blood gas analysis confirmed a true CS sample in 77% of patients using the standard technique and 100% using the modified technique. Conclusions: CS blood sampling via the antecubital fossa is feasible and safe. Blood gas analysis of paired venous and CS samples can be used to confirm a valid CS sample. A coronary guide wire can be used to stabilise the sampling catheter in the CS, and this increases CS sampling accuracy.

Evaluation of Antimicrobial Durability and Anti-Biofilm Effects in Urinary Catheters Against Enterococcus faecalis Clinical Isolates and Reference Strains

Background:Enterococcus faecalis, Escherichia coli, Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans biofilms are major causes of catheter-associated urinary tract infections. Antimicrobial-coated or impregnated urinary catheters are seen as a possible way to prevent these infections.Aims:To determine the biofilm-forming ability of 89 E. faecalis isolates from urinary tract infections and to compare several urinary catheters for antimicrobial durability and the inhibitory effects on biofilm formation of different laboratory strains and clinical isolates of E. faecalis.Study Design:In vitro experimental study.Methods:The biofilm forming ability of E. faecalis isolates was determined by the crystal violet staining and plate counting methods. For comparison of urinary catheters, biofilms of 45 E. faecalis isolates from the catheter samples of hospitalized patients and five laboratory strains of E. coli ATCC25922, S. epidermidis ATCC35984, P. aeruginosa ATCC27853, E. faecalis ATCC29212 and C. albicans ATCC90028 were formed on the catheters in 24-well tissue culture plates. Scanning electron microscopy analysis was performed to observe biofilms.Results:All 89 E. faecalis isolates were found to be biofilm positive. Nitrofurazone-impregnated catheters significantly reduced the cell counts of E. faecalis isolates and completely inhibited the formation of P. aeruginosa and S. epidermidis biofilms compared with the others. Regarding reduction of biofilm cell counts, a hydrophilic-coated catheter was more effective against P. aeruginosa, whereas a silver-coated catheter was found to be more effective against S. epidermidis. The nitrofurazone-impregnated catheter had the best antimicrobial durability.Conclusion:Urine isolates of E. faecalis had considerable ability with respect to biofilm formation. The nitrofurazone-impregnated catheter was the most effective against all tested bacteria; however, the effect of a hydrophilic or silver-coated catheter depends on the species present in it.

Antibiotic Therapy in Comatose Mechanically Ventilated Patients Following Aspiration: Differentiating Pneumonia From Pneumonitis.

To determine the proportion of patients with documented bacterial aspiration pneumonia among comatose ICU patients with symptoms suggesting either bacterial aspiration pneumonia or non-bacterial aspiration pneumonitis. Prospective observational study. University-affiliated 30-bed ICU. Prospective cohort of 250 patients admitted to the ICU with coma (Glasgow Coma Scale score ≤ 8) and treated with invasive mechanical ventilation. None. The primary outcome was the proportion of patients with microbiologically documented bacterial aspiration pneumonia. Patients meeting predefined criteria for aspiration syndrome routinely underwent telescopic plugged catheter sampling during bronchoscopy before starting probabilistic antibiotic treatment. When cultures were negative, the antibiotic treatment was stopped. Of 250 included patients, 98 (39.2%) had aspiration syndrome, including 92 before mechanical ventilation discontinuation. Telescopic plugged catheter in these 92 patients showed bacterial aspiration pneumonia in 43 patients (46.7%). Among the remaining 49 patients, 16 continued to receive antibiotics, usually for infections other than pneumonia; of the 33 patients whose antibiotics were discontinued, only two subsequently showed signs of lung infection. In the six patients with aspiration syndrome after mechanical ventilation, and therefore without telescopic plugged catheter, antibiotic treatment was continued for 7 days. Mechanical ventilation duration, ICU length of stay, and mortality did not differ between the 43 patients with bacterial aspiration pneumonia and the 49 patients with non-bacterial aspiration pneumonitis. The 152 patients without aspiration syndrome did not receive antibiotics. Among comatose patients receiving mechanical ventilation, those without clinical, laboratory, or radiologic evidence of bacterial aspiration pneumonia did not require antibiotics. In those with suspected bacterial aspiration pneumonia, stopping empirical antibiotic therapy when routine telescopic plugged catheter sampling recovered no microorganisms was nearly always effective. This strategy may be a valid alternative to routine full-course antibiotic therapy. Only half the patients with suspected bacterial aspiration pneumonia had this diagnosis confirmed by telescopic plugged catheter sampling.

Application of Laser Light Scattering Technology in Rapid Diagnosis of Urinary Tract Infections and Antimicrobial Susceptibility Testing in a Tertiary Children’s Hospital

BackgroundTimely and accurate microbiology testing is crucial in the diagnosis and management of urinary tract infections (UTIs). The ability to rapidly screen for potential UTIs can lead to early rule out and judicious use of antimicrobial therapy. This study examines the application of laser scattering for bacterial detection and antimicrobial susceptibility testing (AST) directly from urine.MethodsResidual urine samples collected for routine culture were tested using the BacterioScan™ 216Dx™ UTI System and 216R AST System. Continuous collection of light refraction patterns generated growth curve that was used to determine whether the sample was likely positive or negative for bacteria. Further curve analysis ruled out mixed flora at lower concentrations, and “qualified” samples were identified directly on MALDI-TOF MS. AST for ampicillin, cefazolin, ceftriaxone and ciprofloxacin was performed concurrently on the instrument. Samples were incubated for up to 16 hours with results available as early as 2 hours.Results210 urine samples were tested. After 3 hours of incubation on the BacterioScan, 70 (33.3%) and 140 (67.7%) urine samples were reported as positive and negative for bacterial growth, respectively. 136/140 (97.1%) of the negative samples were either no growth (67.6%) or insignificant (32.4%) growth by culture. The remaining 4 (2.9%) were catheter (3) or surgical (1) samples that grew <10K CFU/mL uropathogens, which is below the assay’s LOD. 33/70 (47.1%) samples were tested on the 216R AST System; 37/70 (52.9%) samples omitted by curve analysis showed no or questionable significant growth by culture. Comparator data were available for 26/33 samples. Ampicillin and ceftriaxone demonstrated categorical agreement of 100%, while cefazolin and ciprofloxacin had 96% and 88% agreement, respectively, with 4% major errors for cefazolin and 12% minor errors for ciprofloxacin.ConclusionThe 216Dx UTI System could be utilized as a screening platform to rule out UTIs within 3 hours, with AST available after an additional 2–6 hours for suspect UTI positive samples. This could potentially prevent unnecessary antimicrobial therapy. Preliminary data are promising but testing of additional clinical samples is warranted.Disclosures A. Tomaras, BacterioScan, Inc: Employee, Salary Achaogen: Consultant, Consulting fee Forge Therapeutics: Consultant, Consulting fee Pfizer: Consultant, Consulting fee Spero Therapeutics: Consultant, Consulting fee

ELECTRON MICROSCOPIC ASSAY OF BACTERIAL BIOFILM FORMED ON INDWELLING URETHRAL CATHETERS

Biofilm formation on indwelling urinary catheters is a leading cause of Urinary tract infection (UTI). Presence of biofilm is associated with increased bacterial resistance to antimicrobial therapy and resultant treatment failure. The study detected a reliable method for diagnosis of biofilm formation by comparing scanning electron microscopy (SEM) and tissue culture plate method (TCP). The work was conducted on 20 urinary catheters from patients ranging from 1.5 to 85 years with catheters that remained in situ for a period of 3 to 20 days. Samples of catheters for culture and SEM and samples of urine were taken at the same time. The correlation between renal conditions and biofilm formation was not significant (p=0.336). No significant correlation (p =0.836, 0.163 respectively) was found between predisposing conditions (DM, renal insufficiency, diarrhea and impaired immunity) and development of Catheter associated urinary tract infection ( CAUTI )and biofilm formation. Biofilm formation increased with duration of catheter in situ, but no significant.correlation was found (p=0.095). This could be due to small number of specimens. 9/20(45%) urine samples, 12/20(60%) catheter samples were positive by culture and 14/20(70%) catheters showed biofilm on SEM. 4/12(33.33%) organisms isolated from catheter culture produced biofilm by TCP method. 9 isolates were recovered from 9 positive urine cultures. The microorganisms isolated were non Candida albicans (3/9), E. coli (2/9), C. albicans (2/9) and Acenitobacter (2/9). 14 isolates were recovered from 12 culture- positive catheters. The organisms isolated were E.- coli (3/14), non-Candida albicans (3/14), C. albicans (2/14), C tropicalis (2/14), Acenitobacter (2/14), Klebsiella (1/14) and Enterococcus (1/14). Reduction in microbial diversity with antimicrobial use was noticed but the correlation was insignificant (p=0.317). The correlation between urine culture results as well as catheter culture results and biofilm formation by SEM were both significant (p = 0.008 & 0.000 respectively). The correlation between urine culture and TCP assay was insignificant (p =0.237). Using SEM as the gold standard method for the detection of biofilm, the sensitivity, specificity; total accuracy, PPV & NPV of urine culture and catheter culture were, 64.30%, 100%, 75%, 100%, 54% & 85.70%, 100%, 90%, 100%, 75% respectively.

Increased biofilm formation ability and accelerated transport of Staphylococcus aureus along a catheter during reciprocal movements

Staphylococcus spp. is a major cause of device-related infections. However, the mechanisms of deep-tissue infection by staphylococci from the skin surface remain unclear. We performed in vitro experiments to determine how staphylococci are transferred from the surface to the deeper layers of agar along the catheter for different strains of Staphylococcus aureus with respect to bacterial concentrations, catheter movements, and biofilm formation. We found that when 5-mm reciprocal movements of the catheter were repeated every 8h, all catheter samples of S. aureus penetrated the typical distance of 50mm from the skin to the epidural space. The number of reciprocal catheter movements and the depth of bacterial growth were correlated. A greater regression coefficient for different strains implied faster bacterial growth. Enhanced biofilm formation by different strains implied larger regression coefficients. Increased biofilm formation ability may accelerate S. aureus transport along a catheter due to physical movements by patients.

Urethral catheterization and sperm vitrification for simplified semen banking in felids.

Semen banking of domestic cats and wild felids represents a vital resource for their long-term conservation, but current methods require access to advanced training and specialized equipment. A newer method of semen collection, urethral catheterization of medetomidine-treated cats, allows recovery of high sperm numbers, but it is unclear if this approach permits maximal sperm recovery or is feasible using less expensive alpha-2 agonists. Similarly, a newer sperm preservation approach, vitrification, offers advantages of simplicity and minimal equipment needs, but its efficacy in combination with urethral catheterization has not been investigated. Our specific objectives were to (i) evaluate sequential semen recovery with urethral catheterization and electroejaculation in domestic cats, (ii) assess the effectiveness of a weak (xylazine) versus strong (dexmedetomidine) alpha-2 agonist for inducing sperm release, and (iii) compare post-thaw sperm motility, acrosome status and fertilizing capacity of catheter-recovered samples after vitrification or straw freezing. Results indicated that electroejaculation following repeated catheterization allowed recovery of additional spermatozoa (range, 11-32×106 sperm/male) and that xylazine was ineffective for inducing meaningful sperm release (range, 0-0.4×106 sperm/male). Post-thaw motility and acrosome status of vitrified catheter samples did not differ (p>.05) from that of straw frozen samples. Preliminary results indicated that in vitro fertilization success (9/30, 30%) of vitrified catheter sperm did not differ (p>.05) from that observed with straw frozen samples (17/30, 57%). In conclusion, urethral catheterization of dexmedetomidine-treated cats allows recovery of substantial sperm numbers but electroejaculation still may be warranted for maximal sperm recovery. Xylazine is not suitable as an inexpensive alternative to dexmedetomidine for catheterization. Vitrification of catheter samples results in comparable post-thaw parameters to straw freezing and may be adequate for use with oviductal insemination procedures.

Cardiovascular, respiratory and metabolic responses to apnea induced by atlanto‐occipital intrathecal lidocaine injection in anesthetized horses

ObjectiveTo determine physiologic responses to apnea‐induced severe hypoxemia in anesthetized horses. Study designProspective experimental study. AnimalsSix university‐owned horses with a median (range) body weight of 500 (220–510) kg and aged 13.5 (0.8–24.0) years scheduled for euthanasia. MethodsXylazine–midazolam–ketamine‐anesthetized horses breathing room air spontaneously were instrumented with a facial artery catheter for pressure measurement and blood sampling, and were made apneic with atlanto‐occipital intrathecal lidocaine (4 mg kg−1). Cardiopulmonary, biochemical and hematologic variables were recorded before (baseline) and every minute for 10 minutes after lidocaine injection. ResultsPaO2 values were: baseline, 55 mmHg (7.3 kPa); 1 minute, 28 mmHg (3.8 kPa); 2 minutes, 18 mmHg (2.4 kPa); 3 minutes, 15 mmHg (2.0 kPa), and 4–10 minutes, (8–11 mmHg (1.1–1.5 kPa). PaCO2 values were: baseline, 50 mmHg (6.7 kPa); 1 minute, 61 mmHg (8.1 kPa), and 2–10 minutes, 64–66 mmHg (8.5–8.8 kPa). Base excess values at baseline, 1 minute and 2–10 minutes were 5.3 mmol L−1, 6.5 mmol L−1 and 7.0–8.1 mmol L−1, respectively. Pulse rates at baseline, 1 minute and 2–7 minutes were 36, 53 and 54–85 beats minute−1, respectively. Asystole occurred at 8 minutes. Pulse pressures were 50 mmHg at baseline and 1 minute, and 39 mmHg, 31 mmHg, 22 mmHg, 17 mmHg and 1–9 mmHg at 2, 3, 4, 5 and 6–10 minutes, respectively. Lactate was 0.9 mmol L−1 at baseline, progressively increasing to 1.7–2.4 mmol L−1 at 7–10 minutes. Packed cell volume increased after 7 minutes of apnea. There were no other major changes. Conclusions and clinical relevanceApnea immediately exacerbated hypoxemia and hypercapnia and rapidly caused hemodynamic instability. Apnea in hypoxemic anesthetized horses is associated with a serious risk for progress to cardiovascular collapse.

TCT-602 Identification of local translesional intracoronary gradients of inflammatory biomolecules during PCI procedures using a novel dedicated sampling catheter

TCT-602 Identification of local translesional intracoronary gradients of inflammatory biomolecules during PCI procedures using a novel dedicated sampling catheter

PHENOTYPIC CHARACTERIZATION OF ESCHERICHIA COLI ISOLATED FROM URINE AND STOOL FROM SHORT TERM AND LONG TERM CATHETERIZED PATIENTS

Background: Uropathogenic strains of Escherichia coli possess a number of phenotypic characters which allow them to colonize the catheter and cause infection of the same and the chances of colonization by these micro-organisms increase with the duration of catheterization. Objectives: This study was carried out to understand the differences between the phenotypic characters between the strains of E.coli isolated from the urine and gut of short term catheterized (STC) and long term catheterized (LTC) patients . Materials and Methods: Urine from the catheter and stool sample was processed by standard methods. The following special tests like α-hemolysis, haemagglutination, cell surface hydrophobicity, serum bactericidal assay, biofilm formation and congo red binding assay were performed to detect the phenotypic characters of the isolated E.coli . Antibiotic susceptibility testing was performed by Kirby Bauer method as per the Clinical Laboratory Standards Institute. Results: Majority (93.75%, 75% and 81.25%) of the E.coli isolates from urine of LTC patients were positive for MRHA, cell surface hydrophobicity and resistant to serum killing respectively, while majority (93.75%) of the urine isolates from short term catheterization. On congo red agar, the majority (80% and 60%) of isolates producing rdar type of colony and biofilm respectively,were isolated from urine of long term catheterized patients. ESBL production was noted in 68.75% of the urine isolates from long term catheterized patients. Conclusion: S erum resistance and biofilm formation are significant assays in terms of differentiating between the short term and long term catheterization and by elucidating these mechanisms better, it may become easier to combat and prevent such infections.

Maternofetal pharmacokinetics and fetal lung responses in chronically catheterized sheep receiving constant, low-dose infusions of betamethasone phosphate

Antenatal steroids are standard of care for cases of anticipated preterm labor to improve neonatal outcomes. However, steroids are potent drugs, and their use in pregnancy remains largely unoptimized. The objective of the study was to measure the maternofetal pharmacokinetics of constant, low-dose intravenous betamethasone phosphate infusions and correlate these data with the transcriptional effect exerted by subclinical betamethasone exposures on the ovine fetal lung. Thirty-two ewes carrying a single fetus had surgery to catheterize fetal and maternal jugular veins at 116 days of gestation (term, 150 days). Animals were recovered for 2 days and then were randomized to receive 2 sequential maternal intravenous infusions of either (n= 4/group) of the following: 1) saline, 0.125, 0.04, or 0.0125 mg/kg betamethasone phosphate over 3 hours; or 2) saline, 0.25, 0.08, or 0.025 mg/kg betamethasone phosphate over 12 hours. Each infusion was separated by 2 days. Fetal lung tissue was collected for analysis using quantitative polymerase chain reaction and an ovine-specific microarray. Plasma betamethasone levels from time-course catheter samples were determined by mass spectrometry. Data were assessed for distribution, variance, and tested by an analysis of variance. Betamethasone was detectable (>1 ng/mL) in fetal plasma only in animals randomized to 0.125 mg/kg 3 hour or 0.250 mg/kg 12 hour infusions. Fetal betamethasone half-lives were 1.7-2.8 times greater than maternal values. At maximum concentration, fetal plasma betamethasone levels were approximately 10% of maternal levels. Compared with saline control, all animals, other than those receiving 0.0125 mg/kg 3 hour betamethasone phosphate infusions, had evidence of dose-dependent glucocorticoid transcriptional responses in the fetal lung. Constant maternal betamethasone infusions delivering substantially lower fetal and maternal betamethasone maximal concentrations than those achieved with current clinical treatment protocols were associated with dose-dependent changes in glucocorticoid-response markers in the fetal lung. Further studies to determine the minimally efficacious dose of steroids for improving outcomes in preterm infants should be viewed as a priority.

Rotation Disk Process to Assess the Influence of Metals and Voltage on the Growth of Biofilm.

Biofilms consist of not only bacteria but also extracellular polymer substrates (EPS). They are groups of microorganisms that adhere to each other on a surface, especially as a result of exposure to water and bacteria. They can pose health risks to humans as they grow in hospital settings that include medical supplies and devices. In a previous study, the researchers discovered that bacteria/biofilm grew well on wetted external latex, male catheters. These results concerned the investigators and encouraged them to find ways for prohibiting the growth of bacteria/biofilm on the male catheters (which are made of natural rubber). They carried out a new study to assess the influence of metals and voltage for the growth of bacteria on these latex samples. For this purpose, a unique Rotation Disk Reactor was used to accelerate biofilm formation on external male catheter samples. This setup included a dip tank containing water and a rotating wheel with the attached latex samples (some of which had single electrodes while others had paired electrodes with applied voltage). The process allowed the samples to become wetted and also exposed them to microorganisms in the ambient air during each revolution of the wheel. The results (as viewed from SEM images) showed that when compared to the control sample, the presence of metals (brass, stainless steel, and silver) was generally effective in preventing bacterial growth. Also the use of voltage (9.5 volt battery) essentially eliminated the appearance of rod shaped bacteria in some of the samples. It can be concluded that the presence of metals significantly reduced bacterial growth on latex and the application of voltage was able to essentially eliminate bacteria, providing appropriate electrode combinations were used.

English

Bacterial biofilms forming on indwelling urinary catheters continue to represent a public health problem because they are associated with urinary tract infections (UTIs). This study was undertaken to evaluate the ability of immobilized Lactobacillus acidophilus cells to inhibit biofilm formation on catheter surfaces. Urine bacteria and Lactobacillus species were isolated from urine and vaginal swabs (HVS), respectively. Immobilization of L. acidophilus on catheter samples was achieved using sodium alginate and the inhibition of urine bacteria by the immobilized Lactobacillus cells was evaluated by microscopy and viable cell count procedures following co-culture of the immobilized cells and urine bacteria. Results showed that pre-coating of catheter surfaces with L. acidophilus before exposure to urine bacteria significantly (p&lt;0.05) reduced attachment of some urine bacteria to the catheter surfaces. Staphylococcus aureus, Klebsiella and Escherichia coli were significantly inhibited, while Pseudomonas aeruginosa was not inhibited. Furthermore, crude bacteriocin preparations from the Lactobacillus cells had antimicrobial activity against the urine bacteria. This study shows that pre-coating of catheter surfaces with L. acidophilus could be an effective strategy for controlling biofilm formation on urinary catheters. Key words: Biofilm, catheter, Lactobacillus, immobilization, sodium alginate. &nbsp