Jugular Catheter Research Articles

A cross-sectional study on non-infectious dysfunction of hemodialysis cuffed catheter.

Dialysis cuffed catheter dysfunction results in inadequate dialysis, increased sepsis risk,and a shortenedcatheter life. It may be possible to prolong catheter function by identifying the causes of cuffed catheter dysfunction. This study was a cross-sectional descriptive study conducted in 2021-2022 on hemodialysis patients with jugular cuff catheters. The catheterizations were performed using the Seldinger technique and were confirmed by fluoroscopy. A 12-month follow-up was conducted with respect to the performance of the cuffed catheter. A total of 123 patients underwent hemodialysis over 2 years via a cuffed catheter. Catheters were most commonly inserted into the right internal jugular vein, with lengths of 19 cm (tip to cuff). The rate of dysfunction of cuffed catheters was 27.6%. Catheter-related thrombosis was the most common cause in 10 cases (29.4%), followed by catheter tip fibrin sheath in 8 cases (23.5%) and catheter tip malposition in 8 cases (23.5%). Furthermore, 18 patients (52.94%) of cuffed catheter dysfunction occurred within 3 months of catheter placement, based on our study. The dysfunction of cuffed catheters on the left side 23 (67.64%) is more prevalent than the right side 11 (32.35%) (P=0.043); the malposition of catheter tips is more prevalent on the left side (P=0.023). Most commonly, cuffed catheter dysfunction is caused by thrombosis, fibrin sheath formation, and catheter tip malposition. Cuffed catheter failure can be reduced by carefully monitoring the catheter's path and tip position, searching for fibrin sheaths when investigating cuffed catheter failure, and preventing thrombotic events.

Citrulline and ADI-PEG20 reduce inflammation in a juvenile porcine model of acute endotoxemia.

Arginine is a conditionally essential amino acid that is depleted in critically ill or surgical patients. In pediatric and adult patients, sepsis results in an arginine-deficient state, and the depletion of plasma arginine is associated with greater mortality. However, direct supplementation of arginine can result in the excessive production of nitric oxide (NO), which can contribute to the hypotension and macrovascular hypo-reactivity observed in septic shock. Pegylated arginine deiminase (ADI-PEG20, pegargiminase) reduces plasma arginine and generates citrulline that can be transported intracellularly to generate local arginine and NO, without resulting in hypotension, while maintaining microvascular patency. The objective of this study was to assess the efficacy of ADI-PEG20 with and without supplemental intravenous citrulline in mitigating hypovolemic shock, maintaining tissue levels of arginine, and reducing systemic inflammation in an endotoxemic pediatric pig model. Twenty 3-week-old crossbred piglets were implanted with jugular and carotid catheters as well as telemetry devices in the femoral artery to measure blood pressure, body temperature, heart rate, and respiration rate. The piglets were assigned to one of three treatments before undergoing a 5h lipopolysaccharide (LPS) infusion protocol. Twenty-four hours before LPS infusion, control pigs (LPS; n=6) received saline, ADI-PEG20 pigs (n=7) received an injection of ADI-PEG20, and seven pigs (ADI-PEG20 + CIT pigs [n=7]) received ADI-PEG20 and 250 mg/kg citrulline intravenously. Pigs were monitored throughout LPS infusion and tissue was harvested at the end of the protocol. Plasma arginine levels decreased and remained low in ADI-PEG20 + CIT and ADI-PEG20 pigs compared with LPS pigs but tissue arginine levels in the liver and kidney were similar across all treatments. Mean arterial pressure in all groups decreased from 90 mmHg to 60 mmHg within 1h of LPS infusion but there were no significant differences between treatment groups. ADI-PEG20 and ADI-PEG20 + CIT pigs had less CD45+ infiltrate in the liver and lung and lower levels of pro-inflammatory cytokines in the plasma. ADI-PEG20 and citrulline supplementation failed to ameliorate the hypotension associated with acute endotoxic sepsis in pigs but reduced systemic and local inflammation in the lung and liver.

Selective and Concentrative Enteropancreatic Recirculation of Antibiotics by Pigs.

Antibiotics that are efficacious for infectious pancreatitis are present in pancreatic exocrine secretion (PES) after intravenous administration and above minimal inhibitory concentrations. We measured concentrations of four antibiotics by tandem liquid chromatography-mass spectroscopy in plasma and PES after enteral administration to juvenile pigs with jugular catheters and re-entrant pancreatic-duodenal catheters. Nystatin, which is not absorbed by the intestine nor used for infectious pancreatitis (negative control), was not detected in plasma or PES. Concentrations of amoxicillin increased in plasma after administration (p = 0.035), but not in PES (p = 0.51). Metronidazole and enrofloxacin that are used for infectious pancreatitis increased in plasma after enteral administration and even more so in PES, with concentrations in PES averaging 3.1 (±0.5)- and 2.3 (±0.6)-fold higher than in plasma, respectively (p's < 0.001). The increase in enrofloxacin in PES relative to plasma was lower after intramuscular administration (1.8 ± 0.5; p = 0.001). The present results demonstrate the presence of a selective and concentrative enteropancreatic pathway of secretion for some antibiotics. Unlike the regulated secretion of bile, the constitutive secretion of PES and intestinal reabsorption may provide a continuous exposure of pancreas tissue and the small intestine to recirculated antibiotics and potentially other therapeutic molecules. There is a need to better understand the enteropancreatic recirculation of antibiotics and the associated mechanisms.

Intravenous infusion of 5-hydroxytryptophan to mid-lactation Holstein cows transiently affects milk production and circulating amino acid concentrations

In dairy cows, the lactating mammary glands synthesize serotonin, which acts in an autocrine-paracrine manner in the glands and is secreted into the periphery. Serotonin signaling during lactation modulates nutrient metabolism in peripheral tissues such as adipose and liver. We hypothesized that the elevation of circulating serotonin during lactation would increase nutrient partitioning to the mammary glands, thereby promoting milk production. Our objective was to elevate circulating serotonin via intravenous infusion of the serotonin precursor 5-hydroxytryptophan (5-HTP) to determine its effects on mammary supply and extraction efficiency of AA, and milk components production. Twenty-two multiparous mid-lactation Holstein cows were intravenously infused with 5-HTP (1 mg/kg body weight) or saline, in a crossover design with two 21-d periods. Treatments were infused via jugular catheters for 1 h/d, on d 1 to 3, 8 to 10, and 15 to 17 of each period, to maintain consistent elevation of peripheral serotonin throughout the period. Milk and blood samples were collected in the last 96 h of each period. Whole-blood serotonin concentration was elevated above saline control for 96 h after the last 5-HTP infusion. Dry matter intake was decreased for cows receiving 5-HTP, and on average they lost body weight over the 21-d period, in contrast to saline cows who gained body weight. Milk production and milk protein yield were lower in cows receiving 5-HTP during the 3 infusion days, but both recovered to saline cow yields in the days after. Although milk fat yield exhibited a day-by-treatment interaction, no significant difference occurred on any given day. Milk urea nitrogen concentration was lower in 5-HTP cows on the days following the end of infusions, but not different from saline cows on infusion days. Meanwhile, plasma urea nitrogen was not affected by 5-HTP infusion. Circulating concentrations of AA were overall transiently decreased by 5-HTP, with concentrations mostly returning to baseline within 7 h after the end of 5-HTP infusion. Mammary extraction efficiency of AA was unaffected by 5-HTP infusion. Overall, both lactation performance and circulating AA were transiently reduced in cows infused with 5-HTP, despite sustained elevation of circulating serotonin concentration.

Using central venous pressure waveform to confirm the placement of an internal jugular central venous catheter in the intensive care unit

BackgroundA mobile chest X-ray is traditionally performed to confirm the position of an internal jugular central venous catheter (CVC) after placement in the intensive care unit (ICU). Using chest radiography to confirm CVC position often results in delays in authorising the use of the CVC, requires the deployment of additional human resources, and is costly. ObjectiveThis study aimed to determine the feasibility and accuracy of using the central venous pressure (CVP) waveform to confirm the placement of internal jugular CVCs. MethodsThis retrospective study was conducted in a single quaternary ICU over a 6-month period. We included adult patients who had internal jugular CVC inserted and CVP transduced as part of their routine care in the ICU. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CVP waveform analysis in confirming the position of internal jugular CVC relative to chest radiography were calculated. ResultsA total of 241 internal jugular CVCs were inserted (in 219 patients, 35.6% female), and the CVP waveform was assessed. In 231 cases, this suggested adequate placement in a central vein, which corresponded with a correct position on subsequent chest X-ray. On six occasions, the CVP waveforms were interpreted as suboptimal; however, on chest X-rays, the CVCs were noted to be in a suitable position (sensitivity: 97.5%). Four suboptimal CVP waveforms were obtained, and they correctly identified CVC malposition on subsequent chest X-ray (specificity: 100%). The average time from CVC insertion to radiological completion was 118 minutes. ConclusionCVP waveform analysis provides a feasible and reliable method for confirming adequate internal jugular CVC position. The use of chest radiography can be limited to cases where suboptimal CVP waveforms are obtained.

Head-mounted central venous access during optical recordings and manipulations of neural activity in mice.

Establishing reliable intravenous catheterization in mice with optical implants allows the combination of neural manipulations and recordings with rapid, time-locked delivery of pharmacological agents. Here we present a procedure for handmade jugular vein catheters designed for head-mounted intravenous access and provide surgical and postoperative guidance for improved survival and patency. A head-mounted vascular access point eliminates the need for a back-mounted button in animals already receiving neural implants, thereby reducing sites of implantation. This protocol, which is readily adoptable by experimenters with previous training and experience in mouse surgery, enables repeated fiber photometry recordings or optogenetic manipulation during drug delivery in adult mice that are awake and behaving, whether head fixed or freely moving. With practice, an experienced surgeon requires ~30 min to perform catheterization on each mouse. Altogether, these techniques facilitate the reliable and repeated delivery of pharmacological agents in mouse models while simultaneously recording at high temporal resolution and/or manipulating neural populations.

Analysis of tip malposition and correction of peripherally inserted central catheters under ultrasound-guidance: 5-year outcomes from a single center.

Peripherally inserted central catheter (PICC) has become a common procedure. Although ultrasound (US)-guidance has improved success rates, a small percentage of malposition is inevitable. The purpose of our study is to evaluate malposition rates of US-guided bedside PICC catheter insertion, and the clinical factors associated with malposition. This is a retrospective cohort study evaluating 5981 patients who had undergone ultrasound-guided bedside PICC placement from January 2017 to December 2021 at a single tertiary center. Final tip location was confirmed on chest radiograph. Patients were categorized into optimal, suboptimal, and malposition groups according to final tip location. 4866 cases (81.7%) showed optimal tip position, 790 (13.3%) were suboptimal, and 299 (5.0%) were malpositioned. Logistic regression analysis identified six variables associated with tip malposition; height (odds ratio (OR) 1.044; 95% confidence interval (CI), 1.028-1.061; p < 0.001), body mass index (BMI) (OR 1.051; 95% CI, 1.017-1.087; p = 0.003), prior failure at accessing peripheral intravenous (IV) access (OR 1.718; 95% CI, 1.215-2.428; p = 0.002), side of the arm (OR 3.467; 95% CI, 2.457-4.891; p < 0.001), length of the catheter (OR 0.763; 95% CI, 0.734-0.794; p < 0.001), and number of previous central catheter insertions (OR 1.069; 95% CI, 1.004-1.140; p = 0.038). Malpositioned catheters were corrected by either bedside repositioning, bedside reinsertion, fluoroscopic reinsertion, switching to jugular catheters or catheter removal. No patient related factors were significantly associated with malposition or success of reposition. US-guidance can help reduce catheter malposition during bedside PICC insertion. Patients with risk factors such as multiple previous central vein insertions, failed peripheral line insertions, left arm insertion, or high BMI should undergo thorough sonographic evaluation of the arm vessels to prevent malposition.

Catheterisation of the jugular vein of 12-day-old suckling piglets group-housed with littermates and the sow

Collection of blood samples by venipuncture requires isolation, restraint and immobilisation, which is stressful for piglets and may result in unreliable readings. A jugular vein catheter allows frequent blood sampling with minimal stress to the piglets. Techniques for jugular vein catheter implantation in older pigs have been described, but less information is available for suckling piglets. This report describes the procedure of catheter implantation into an external jugular vein for longer-term frequent blood sampling in 48 12-day (d)-old suckling German Landrace piglets with a mean BW of 3.4 ± 0.7 kg. Catheterisation was performed either under general anaesthesia by injection of azaperone and ketamine (a/k) or by inhalation of isoflurane (IsoF). To determine the optimal incision site in the sulcus jugularis, the centre between the caudal edge of the mandibula, cranial shoulder and sternum was identified. After a small incision of the skin, the jugular vein was bluntly dissected and a catheter was inserted. The tip of the catheter was placed near the beginning of the right atrium. After wound closure, the surgical area was secured by disinfection and bandages. The piglets were returned to their littermates in the farrowing pen immediately after full recovery from anaesthesia, which was 5–7 h in a/k and 0.75 h in IsoF anaesthetised piglets after the onset of the surgery, respectively. The catheter was flushed daily with 0.9% NaCl-0.1% sodium citrate solution. To demonstrate the longer-term benefits of the catheter, on d 4 after surgery, a series of frequent blood sampling were performed after an oral xylose bolus. In total, 10 samples of 0.5 mL were taken before and every 30 min after the oral xylose bolus for 5 h; the blood volume was replaced with 0.9% NaCl solution. On d 4 after surgery, 41 of 48 implanted catheters were considered fully functional (90% of desired samples collected), three as partially functional, and four as non-functional, whereas two catheters were non-functional already from d 1 after surgery. The catheterised animals remained clinically healthy but showed less daily BW gain from age d 12 (day of surgery) to d 15 than non-catheterised control animals (0.12 ± 0.01 vs 0.23 ± 0.01 kg; n = 46; P < 0.05). In conclusion, the catheter implanted into an external jugular vein in 12-d-old suckling piglets remaining with the sow was patent for 4 d after surgery and allowed frequent blood sampling with minimal stress for the piglets.

Pharmacokinetics of hydrorphone hydrochloride after intravenous and subcutaneous administration in ferrets (Mustela putorius furo)

ObjectiveTo determine the pharmacokinetic profile of hydromorphone 0.2 mg kg–1 administered by the intravenous (IV) and subcutaneous (SC) route in ferrets. Study designRandomized, crossover study. AnimalsA group of eight adult ferrets weighting (mean ± standard deviation) 1.02 ± 0.22 kg. MethodsHydromorphone hydrochloride 0.2 mg kg–1 was administered IV or SC with a washout period of 7 days. Blood samples were collected from a jugular catheter before administration of hydromorphone and at 5, 10, 15, 20, 30, 45, 60, 90, 120, 240, 360, 480 and 720 minutes after hydromorphone administration. Plasma hydromorphone concentrations were determined by liquid chromatography/tandem mass spectrometry. Data were analyzed using a non-linear mixed effects model. ResultsThe hydromorphone effective half-life was (t1/2) 45 min–1. Systemic clearance (Cls) and the volume of distribution (Vdss) following IV administration were 84.8 mL kg–1 min–1 and 5.59 L kg–1, respectively. The maximum observed plasma concentration was 59.53 ± 14.02 ng mL–1 within 10 minutes following SC administration. The SC bioavailability was 102.0%. Conclusions and clinical relevanceAdministration of IV and SC hydromorphone (0.2 mg kg–1) was characterized by a high clearance, short terminal half-life and large volume of distribution. Hydromorphone plasma concentrations remained greater than 2 ng mL–1 for 2 hours in most ferrets, a threshold reported to provide antinociceptive effects in other species. Hydromorphone was well absorbed following SC injection, providing an alternative administration route for clinical use in ferrets.

Accidental ketamine administration in a horse supposed to undergo general anaesthesia for tenovaginoscopy: Errors and the need of Morbidity and Mortality Rounds in veterinary medicine

AbstractAn 11‐year‐old, 500 kg, healthy mare was admitted for tenovaginoscopy. A jugular venous catheter was inserted to administer detomidine for diagnostic imaging and for anaesthesia‐related drug administration. The horse was premedicated with intramuscular acepromazine and intravenous flunixin. For sedation, 7.5 mL of a solution, presumed to be xylazine 2%, was drawn up in a syringe and labelled with a sticker. Two minutes after injection of 7.5 mL from xylazine‐labelled syringe, the horse showed severe ataxia and fell. Nystagmus and catatonia appeared while one person sat on its neck, to prevent it from rising. After 8 minutes, the horse could not be kept down and took several uncoordinated attempts to stand, still showing nystagmus and ataxia for several minutes. The xylazine‐labelled syringes were analysed. They contained pure ketamine. This case report should raise awareness about clinical errors, a healthy error culture and use of Morbidity and Mortality Rounds to improve patient and personnel care.

Neck Horn Formation After Jugular Vein Catheterization For Haemodialysis: Case Report

Background: Haemodialysis is an essential life-saving procedure for persons suffering from kidney failure. Haemodialysis is usually aceived by central venous catheterization. Neck hornformation is one of the most serious and seldom complications of the procedure.&#x0D; Case Report: A haemodialysis catheter was placed in a 43-year-old man's right internal jugular vein after his arteriovenous fistula failed. After having the catheter removed, a neck horn developed at the puncture site. Horn resection and thrombus evacuation were the surgical treatment methods used.&#x0D; Conclusion: Neck horn following an internal jugular catheter insertion might be dangerous if left untreated. The horn and thrombus are best removed surgically and treated with antibiotics.

PSVI-8 Bisphosphonate Pharmacokinetics in Juvenile Horses

Abstract Bisphosphonates alter bone metabolism via inhibition of osteoclastic bone resorption. Although bisphosphonates are beneficial to treat bone disease, extra-label use in healthy juvenile horses may interfere with normal bone metabolism. The objective was to determine plasma pharmacokinetics of the bisphosphonate clodronate disodium (CD) following a single intramuscular dose to better define the time course of CD in juvenile horses. Ten yearling Quarter Horses (334 ± 18 kg, 504 ± 13 d of age) were used to test the hypothesis that juvenile horses would have faster clearance rate of CD compared with previously published data in adult horses. Horses were placed in individual stalls, jugular intravenous catheters were inserted, and an initial blood sample (0 h) was collected. Horses were administered CD intramuscularly at 1.8 mg/kg BW per label. Plasma samples were collected at 0.5, 1, 3, 6, 12, 24, 48, and 72 h post-administration. Plasma concentration of clodronate was determined by liquid chromatography tandem mass spectrometry. Pharmacokinetic parameters were calculated using a two-compartment model. Blood chemistry parameters [blood urea nitrogen (BUN), creatinine, alkaline phosphatase (ALKP), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), and creatine kinase (CK)] were determined via a commercial laboratory. Included blood chemistry parameters were analyzed for an effect of time using PROC Mixed of SAS. Clodronate was detected in plasma up to 72 h post-administration. Maximum plasma concentration (43,971 ± 25,920 ng/mL) was reached at 0.5 h post-administration. Analysis revealed bicompartmental kinetics with distribution and terminal half-lives of 1.9 ± 0.4 h and 24.4 ± 4.3 h, respectively. Area under the curve to last sample was 22,755 ± 11,426 ng*h/mL and extrapolated to infinity was 26,778 ± 12,465 ng*h/mL. Blood chemistry parameters varied over time within normal ranges. Markers of renal function, BUN and creatinine, decreased from h 0 to h 72 (P &amp;lt; 0.01). Liver function markers ALKP and AST were not affected by CD treatment (P &amp;gt; 0.27). However, GGT and CK changed over time (P &amp;lt; 0.01), with GGT greater at 48 h than other time points, and CK increasing from 0.5 to 24 h before decreasing by 72 h but remaining above baseline. Plasma clodronate concentrations were greater in juvenile horses than previously reported in mature horses (Krueger et al., 2020, Equine Vet J.; Knych et al., 2022, Equine Vet J.). Further, the observed bicompartmental kinetics differed from the linear kinetics previously reported in mature horses whereby juvenile horses from the current study had greater exposure to CD over time as indicated by a longer terminal half-life. Moreover, the single intramuscular dose of CD (1.8 mg/kg BW) did not cause markers of kidney or liver function to deviate from normal ranges in juvenile Quarter Horses.

27 Neurokinin B, Kisspeptin, and Gnrh Hormone Analogs Fail to Stimulate Secretion of Luteinizing Hormone (LH) in KISS1 Knockout Boars

Abstract We generated kisspeptin knockout (KISS1-/- ) pigs exhibiting hypogonadotropic hypogonadism and pubertal failure. Humans and rodents with inactivating KISS1 mutations exhibit increased gonadotropin secretion in response to GnRH and kisspeptin analogs, but it is unknown if KISS1-/- pigs respond similarly. Our goal was to define endocrine responses of KISS1-/- boars to hormone agonists that target different levels of the hypothalamic-pituitary-gonadal axis. Boars (302.6 ± 0.9 d of age) were fitted with indwelling jugular catheters to collect serial blood samples. Serum concentrations of LH and testosterone were quantified with radioimmunoassay. Data were analyzed as repeated measures with genotype (KISS1+/+ ; KISS1+/- ; KISS1-/- ) and time as fixed effects. Blood samples were collected beginning 60 to 120 min before a bolus injection (i.v.) of the agonist and continued for 5 to 48 h after treatment, depending on experiment, with at least 1 wk between studies. Boars received an agonist of either: 1) neurokinin B (senktide; 10 mg/kg BW; Exp. 1); 2) kisspeptin (C6; 15 nMol/kg BW; Exp. 2); 3) GnRH (cystorelin, 150 ng/kg BW; Exp. 3); or 4) LH (hCG; 20 IU/kg BW; Exp. 4). There was a genotype x time interaction for all experiments (P &amp;lt; 0.09). In the 60 min following senktide treatment (Exp. 1), mean LH increased 2.5-fold in KISS1+/+ and KISS1+/- boars, but was unchanged in KISS1-/- boars (P &amp;lt; 0.04). In Exp. 2, C6 increased LH concentrations in KISS1+/+ and KISS1+/- boars within 10 min (P &amp;lt; 0.05) and LH did not return to baseline until 28 h after treatment. However, secretion of LH in KISS1-/- boars was unaffected by C6. Next, cystorelin treatment (Exp. 3) increased circulating LH (P &amp;lt; 0.05) in KISS1+/+ and KISS1+/- males (2.1 ± 0.2 ng/mL), but not in KISS1-/- boars (0.5 ± 0.2 ng/mL). In Exp. 4, hCG increased mean testosterone concentrations for 48 h in KISS1+/+ (32.9 ± 6.7 ng/mL) and KISS1+/- (26.7 ± 4.7 ng/mL) boars, but testosterone in KISS1-/- animals remained at near undetectable levels after hCG administration. Therefore, we have shown for the first time that both neurokinin B and kisspeptin agonists (senktide and C6, respectively) stimulate robust secretion of LH in pigs. In addition, these agonists stimulate similar secretory patterns of LH in KISS1+/+ and KISS1+/- boars, confirming that a single functional copy of KISS1 is sufficient to confer normal reproductive endocrine function in pigs. Failure of a GnRH agonist to stimulate LH secretion in KISS1-/- boars likely reflects insufficient pituitary stores of LH, resulting from a lack of GnRH priming, and underlies the inability of either senktide or C6 to stimulate LH secretion in these animals. Lack of hCG-stimulated testosterone secretion in KISS1-/- boars may indicate a gonadotropin-independent deficit in testicular Leydig cells.

165 Evaluation of the Use of Prenatal Immune Stimulation on the Ability to Alter Postnatal Immune Function in Weaned Pigs

Abstract One of the most lacking areas where improvements can be made in swine production is in the area of swine health. This study was designed to determine whether exposure to low dose endotoxin (lipopolysaccharide; LPS) during gestation can enhance immunity to a subsequent LPS challenge in piglets after weaning. Pregnant Camborough sows (parity: 2.6 ± 1.4) were assigned to prenatal immune stimulation (LPS; n = 7; administered 2.5 µg/kg BW LPS i.m. at d 78 ± 1.8 of gestation) or saline treatment groups (CON; n = 7). From the 2 prenatal treatment groups, barrows (n = 17 LPS, 17 CON) were identified at weaning (21 ± 1.3 d of age) to subsequently receive a post-weaning LPS challenge. On d -7, barrows were transported to the USDA-ARS Livestock Issues Research Unit in Lubbock, TX where they were housed in individual pens in an environmentally controlled building with ad libitum access to water and a starter ration. On d -1, pigs were fitted with indwelling jugular catheters and subcutaneous temperature loggers. On d 0, pigs were challenged i.v. with LPS (10 µg/kg BW) and blood samples were collected at -2, 0, 1, 2, 4, 6, 8, 12, and 24 h relative to LPS challenge. Data were analyzed using PROC MIXED in SAS, specific for repeated measures. There was a treatment × time interaction for subcutaneous temperature (P &amp;lt; 0.01), where temperature increased more quickly at 1 and 2 h post-challenge in LPS compared with CON pigs. There was a tendency (P = 0.08) for less change in white blood cells, relative to baseline values, in LPS compared with CON pigs. There was a treatment × time interaction (P = 0.01) for lymphocyte concentrations where concentrations were reduced in LPS compared with CON pigs at 8 h post-challenge. There was also a treatment × time interaction (P = 0.01) for the change in eosinophil concentrations, where there was less change in eosinophil concentrations from 1 to 12h in LPS compared with CON pigs. There was a tendency (P = 0.08) for a treatment × time interaction for serum interleukin-6 (IL-6), where concentrations were reduced in LPS compared with CON pigs at 2h (P = 0.01) and tended to be reduced at 1 and 4h post-challenge (P ≤ 0.11). There was a tendency (P = 0.06) for a treatment × time interaction for IL-8, where concentrations were reduced in LPS compared with CON pigs at 1 and 4h (P ≤ 0.01) and tended to be reduced at 2h post-challenge (P = 0.06). Granulocyte macrophage colony stimulating factor and tumor necrosis factor-α tended (P ≤ 0.08) to be reduced in LPS compared with CON pigs. These data suggest that exposure to endotoxin in utero can influence the postnatal innate immune response to endotoxin. Thus, it is possible to influence the innate immune response of pigs in utero, which may serve as a method to positively influence postnatal immune responsiveness.

Tunneled femoral dialysis catheters and factors affecting their outcome: a single institution experience.

To assess a single-center experience with tunneled femoral dialysis catheter usage and outcomes and to identify any operator-dependent factors related to risk of premature catheter failure. Retrospective review of the institutional radiology information system for tunneled femoral dialysis catheter placement from 2010 to 2017 was performed. Patients for whom the catheter was placed for an indication other than dialysis or who were less than 18 years of age at the time of catheter placement were excluded. Premature catheter failure rate, cause of premature failure, catheter patency (in days) and infection rate were assessed. Operator/placement characteristics, including laterality, catheter tip placement, and catheter length were also assessed. A total of 101 patients were included in the study. This included n = 116 catheter placements. Thirty-four percent of patients (n = 40) were lost to follow-up, resulting in n = 61 patients and n = 76 catheters analyzed. Premature catheter failure rate was 48% (n = 36), with low flows being the foremost cause of failure (64%, n = 23). Average primary patency of these catheters was 82.4 days (1-328 days). About 8% of catheters (n = 3) were complicated by infection, resulting in an infection rate of 0.4/1000 catheter days. None of the operator-dependent factors analyzed, including catheter laterality, catheter tip placement, and catheter length, demonstrated a significant association with premature catheter failure. Institutional primary access patency rates are comparable to or higher than previously published data, while infection rates are similar to or lower than those reported in the literature. None of the operator-dependent factors related to placement was shown to significantly decrease the risk of premature catheter failure. These findings suggest that while femoral dialysis catheters do not function well in the long term relative to internal jugular vein dialysis catheters, prior literature may undervalue their utility and function, particularly given that these catheters are used as a "last resort" for many patients.

34 Assessing the Ability to Immunomodulate the Innate Immune System and Oxidative Status of Weaned Pigs Through a Prenatal Lipopolysaccharide Challenge

Abstract Gastrointestinal immunity and antioxidant defenses may be bolstered in young animals through prenatal immune system stimulation (PIS), but this is largely uninvestigated in swine. The objective of this experiment was to determine if a low dose of lipopolysaccharide (LPS) administered to late-gestating sows would alter the immune response and oxidative status of subsequent offspring. On d 78 ± 1.8 of gestation, 14 Camborough sows (Parity = 2.6±1.4) of the same farrowing group were blocked by body weight and randomly assigned to one of two treatments: intramuscular injection of saline (CON) or LPS from E. coli O111:B4 (2.5 µg/kg of BW). Sow rectal temperatures (RT) and sickness behavior scores (SBS) were recorded every 0.5 h from -0.5 h to 8 h and every 8 h from 8 to 48 h post-treatment. A subset of 34 weaned barrows (n = 17 CON, LPS; weaning age 21 ± 1.3 d) from the experimental sow group were transported on d -7 to an environmentally controlled facility where they were individually housed with ad libitum access to water and feed. On d -1, pigs were anesthetized for placement of a subcutaneous temperature logger and a jugular catheter. On d 0, all pigs were challenged intravenously with the same LPS strain (10 µg/kg of BW) previously administered to sows. Body temperature was measured at 5-min intervals from the time of logger placement. Blood samples were collected at -2, 0, 1, 2, 4, 6, 8, 12, and 24 h relative to LPS administration at 0 h. After the 24 h blood collection, pigs were necropsied for ileal and jejunal tissue. Plasma samples, jejunal and ileal tissues were analyzed for total antioxidant capacity (TAC) and malondialdehyde (MDA). Data were analyzed as a linear mixed model using PROC MIXED (SAS 9.4) with treatment and time as fixed effects. A dependent covariance structure was used for repeated measurements. Sows administered LPS had elevated RT from 2 to 16-h post-challenge with return to baseline by h 24, indicating mild immune stimulation (treatment × time; P &amp;lt; 0.01). Similarly, sows exposed to LPS had increased SBS from 2 to 3.5 h post-challenge (treatment × time; P &amp;lt; 0.01). Pigs exposed to PIS had greater body temperature than CON at 1 and 2 h post-LPS (treatment × time; P &amp;lt; 0.01). An increase in plasma TAC at 2 and 4 h post-LPS was observed in pigs exposed to PIS relative to CON (treatment × time; P &amp;lt; 0.01). Irrespective of treatment, LPS increased plasma MDA from 2 to 24 h post-challenge (time; P &amp;lt; 0.01). There was no effect of PIS on ileal or jejunal tissue TAC (P ≥ 0.40), but weaned pigs exposed to PIS had decreased jejunal MDA (P &amp;lt; 0.05). Collectively, it appears PIS may alter the innate immune response and oxidative status of the weaned pig during LPS challenge.

PSVI-1 Effect of Soy co-Products in Supplements for Growing Cattle on Hemocytology Following a Lipopolysaccharide Challenge

Abstract The objective of this study was to determine the effect of including soy co-products (soybean meal and soy oil) in the diet on the hemocytology of cattle after an endotoxin challenge. For the growing phase, crossbred Angus steers (n = 36; initial body weight = 289 ± 31 kg) were stratified by body weight and sire and randomly assigned to pastures (n = 9; 0.45 ha mixed grass). Pastures were assigned randomly to 1 of 3 dietary treatments: 1) a control supplement containing no soy co-products (CON); 2) a supplement containing soybean meal (SBM); or 3) a supplement containing soy oil (SBO). All supplements were isonitrogenous and isoenergetic. Cattle were fed supplements (2.45 kg DM/day) for 56 days. At the conclusion of the growing phase, cattle were assigned randomly to 1 of 2 groups for a lipopolysaccharide (LPS) challenge (i.v. infusion of 0.5 µg LPS/kg of body weight). A minimum of 18 hours before sampling, cattle were fitted with jugular vein catheters and placed into stanchions. Blood was collected starting 2 hours before LPS infusion (-2 hr), immediately prior to LPS infusion (0 hr), and at 2, 4, 6, and 8 hr. Statistical analyses were performed using the MIXED procedure of SAS 9.4 as repeated measures with treatment, time, and treatment × time interaction as fixed effects, challenge group as random effect, and calf specified as the subject. Statistical significance was declared at P ≤ 0.05 and tendencies declared at 0.05 &amp;lt; P ≤ 0.1. There were treatment × time interactions for neutrophils (P = 0.003), percentage of neutrophils (P = 0.002), percentage of lymphocytes (P = 0.006), and neutrophil/lymphocyte ratio (NE:LY ratio; P = 0.001). Briefly, neutrophils, percentage of neutrophils, and NE:LY ratio were decreased in cattle on CON diets compared with SBM at -2 h and 0 h (P &amp;lt; 0.01). Also, the percentage of neutrophils were greater at 8 h for cattle on SBO diets than SBM diets (P = 0.018). The percentage of lymphocytes were greater in cattle on the CON diets compared with the SBM diets at 0 and -2 h (P &amp;lt; 0.015). There was a treatment effect for percentage of monocytes (P = 0.035), as the CON diet had greater monocyte percentage compared with the SBM diet, and the SBO diet tended to have greater monocyte percentage compared with SBM diet. There was a time effect for all other hematology variables (P &amp;lt; 0.0001), as leukocytes were typically greater pre-administration of LPS, sharply decreased at 2 and 4 h post-administration of LPS and began to increase at 6 and 8 h. Preliminary results indicated that the inclusion of soy co-products in growing cattle diets influenced hemocytology.

Evaluation of Substance P concentrations in the blood plasma of jugular and tail vein of healthy German Simmental cows

BackgroundCattle strongly mask their pain, making the recognition and assessment of pain difficult. Different subjective and objective parameters to assess pain have been described. Substance P (SP), which is a neurotransmitter, is used to objectively evaluate nociception in cattle. However, SP concentrations have mainly been described in diseased animals, or animals subjected to painful procedures. To this day, no evaluation of SP in healthy adult cattle has been published.The objectives of this pilot study were to 1) assess the SP concentrations in healthy adult German Simmental cattle in the blood plasma, 2) compare the concentrations between the blood of the jugular and the tail vein, and 3) assess the concentrations in the blood of the tail vein every 6 h over a period of 24 h.A total of 52 healthy cattle of the German Simmental breed were included in this study. Animals were 5.0 ± 1.3 (mean ± SD) years old and between 117 and 239 (175.0 ± 34.1) days in milk. Blood samples were taken from the jugular vein (BJV, 07:45 a.m.) and the tail vein (TV1, 08:00 a.m.) each. Additional blood samples were taken every 6 h over the course of 24 h from the tail vein (TV2 – TV5). SP concentrations were analyzed using a commercial ELISA kit.ResultsMean (± SD) and median SP concentrations were 1.087 ± 436 pg/ml and 984 pg/ml for BJV (range 502 – 2,337 pg/ml), and 920 ± 402 pg/ml and 818 pg/ml for TV1 (range 192 – 2,531 pg/ml), respectively. There was a significantly positive correlation between SP concentrations of BJV and TV1. SP concentrations between BJV and TV1 were significantly different, as were SP concentrations in the tail vein between sampling times over the course of 24 h.ConclusionsThe results of this study show that blood samples to assess SP concentrations in cattle can be taken from the jugular as well as from the tail vein. There are high variations in concentrations between animals, and it is hard to define reference ranges for SP in healthy animals. Repeated blood samples should not be taken by repeated punctation of a vein but by use of a jugular vein catheter, which is a major limitation of the present study.

Assembly of an inexpensive rat jugular catheter button based on a split-septum needleless intravenous system

Rat intravenous self-administration is a widely-used animal model in the study of substance use disorders. Rats are tethered to a drug delivery system usually through a port or button that interfaces the drug delivery system with a chronic indwelling jugular vein catheter. These buttons can be purchased commercially but are costly, presenting a significant economic barrier for many researchers. Many researchers manufacture buttons in-house from a combination of individual custom made and commercially available components, resulting in large variation in terms of how the animals are handled and the longevity of catheter patency. We have developed a jugular catheter button that uses a split septum port to provide snap-on entry of a blunt cannula allowing for quick and easy attachment of the i.v. tubing. The port is constructed from commercially available split septum ports, surgical mesh and small metal cannula. The system is “needleless” which decreases the risk of infection and improves safety. The split-septum buttons are easily sterilized in-house adding to the reliability and decreases in the risk of infection. We have used this easily constructed, and inexpensive button for i.v. self-administration experiments in which 80 % of the rats maintained patency for a minimum of 35 days.•Inexpensive method to construct a self-administration backport button.•Utilizes inexpensive components already found in a research laboratory or commercially available.•Can be sterilized in-house without degrading glue or components.

OR12-04 LEAP2 Deletion Does Not Counteract The Effects Of Ghrelin Deletion During Insulin-Induced-Hypoglycemia

Abstract Disclosure: K. Shankar: None. S. Varshney: None. D. Gupta: None. O. Singh: None. S.B. Ogden: None. S. Osborne-Lawrence: None. N.P. Metzger: None. C.P. Richard: None. J.M. Zigman: Grant Recipient; Self; Novo Nordisk. Objective: The hormones ghrelin and LEAP2 both are endogenous ligands for the growth hormone secretagogue receptor (GHSR). Whereas ghrelin activates GHSR, LEAP2 blocks ghrelin from activating GHSR and also inhibits GHSR constitutive activity. It is via GHSR that the glucoregulatory actions of ghrelin and LEAP2 are mediated. These glucoregulatory actions are highlighted by the findings of severe hypoglycemia in ghrelin-KO mice and LEAP2-overexpressing mice when they are submitted to an acute-on-chronic caloric restriction protocol. Also, recently, our group showed that ghrelin-KO mice require a much higher glucose infusion rate (GIR) and exhibit markedly reduced elevation of counterregulatory hormones when submitted to a hyperinsulinemic-hypoglycemic clamp. In the current study, we investigated the potential of LEAP2 to protect against insulin-induced-hypoglycemia and counteract the effects of ghrelin deletion during the hypoglycemic clamp. Methods: Eight-ten week-old male wild-type (WT), Ghrelin-KO, LEAP2-KO, and LEAP2/Ghrelin-doubleKO (lacking both ghrelin and LEAP2 ) littermates were used for this study (n=7-10 per genotype). Mice were implanted with a right jugular vein catheter. Five days later, hyperinsulinemic-hypoglycemic clamps were performed in conscious, unrestrained mice. A low dose of insulin was infused at 4 mU/kg/min i.v. over 2 hr. A 20% glucose solution was simultaneously infused at a variable rate to achieve hypoglycemia (35–45 mg/dL) during the final 30 min. Blood glucose was measured via tail nicks every 5 min. Results: We were able to achieve the target hypoglycemic range in all four genotypes using this protocol. As compared to WT mice, Ghrelin-KO mice required markedly elevated (∼110% higher) GIRs (10±4 mg/kg/min in WT vs. 22±2 mg/kg/min in Ghrelin-KO mice; p=0.03) by the end of the 2-hr clamp. The GIRs required by LEAP2-KO mice were equivalent to those of WT mice (7±2 mg/kg/min in LEAP2-KO; p=n.s.). Furthermore, although during the first 60 min of the clamp, LEAP2/Ghrelin-doubleKO mice exhibited slightly lower blood glucose levels than the other genotypes and during the middle 60 min of the clamp, they required higher GIRs than the other genotypes, by the end of the 2-hr clamp, their GIRs were similar to Ghrelin-KO mice (25±3 mg/Kg/min in Ghrelin/LEAP2-doubleKO mice, p=n.s.). Conclusions: These data suggest a complex effect of LEAP2 on blood glucose. Alone, LEAP2 deletion does not impact insulin sensitivity. When coupled with ghrelin deletion, LEAP2 deletion lowers fasting blood glucose and causes greater insulin sensitivity early on during the hyperinsulinemic-hypoglycemic clamp. By the end of the clamp, this effect of LEAP2 deletion when coupled to ghrelin deletion is gone. Altogether, these results suggest that LEAP2 deletion does not counteract the effects of ghrelin deletion during insulin-induced hypoglycemia. Presentation: Friday, June 16, 2023