INTRODUCTION: Several studies have demonstrated associations between greater rate/volume of intravenous (IV) fluid administration and poorer clinical outcomes. One postulated mechanism for harm from exogenous fluids is shedding of the endothelial glycocalyx (EG). METHODS: A systematic review using relevant search terms was performed using Medline, EMBASE and Cochrane databases from inception to October 2023. Included studies involved humans where the exposure was rate or volume of IV fluid administration and the outcome was EG shedding. The protocol was prospectively registered on PROSPERO: CRD42021275133. RESULTS: The search yielded 450 articles, with 20 articles encompassing 1960 participants included in the review. Eight studies were randomized controlled clinical trials. Half of studies examined patients with sepsis and critical illness; the remainder examined perioperative patients or healthy subjects. Almost all reported blood measurements of soluble EG components; one study used in vivo video-microscopy to estimate EG thickness. Four of 10 sepsis studies, and 9 of 11 non-sepsis studies, found a positive relationship between IV fluid rate/volume and measures of EG shedding. CONCLUSIONS: A trend toward an association between IV fluid rate/volume and EG shedding was found in studies of stable patients, but was not consistently observed among studies of septic and critically ill patients.
Introduction: Alteration in endothelial function during sepsis is thought to play a key role in the progression of organ failure. We herein compared plasma concentrations of endothelial activation biomarkers vascular endothelial growth factor (VEGF), hyaluronan (HA), plasminogen activator inhibitor-1 (PAI-1) and von Willebrand factor (vWF), as well as inflammatory mediator concentrations (IL-6, IL-8, IL-10, C-reactive protein and monocyte chemoattractant protein-1) in dogs with sepsis to healthy dogs. Methods: This study was a multicenter observational clinical trial conducted at two university teaching hospitals from February 2016 until July 2017. The study included 18 client-owned dogs hospitalized with sepsis and at least one distant organ dysfunction, as well as 20 healthy dogs. Plasma biomarker concentrations were measured using ELISA. Severity of illness in dogs with sepsis was calculated using the 5-variable acute physiologic and laboratory evaluation (APPLEFAST) score. Biomarker concentrations were compared between septic and healthy dogs using linear models. Results: Septic peritonitis was the most frequent source of sepsis (11/18; 61%), followed by pneumonia (4/18; 22%). Ten dogs (56%) had only 1 organ dysfunction, whereas 3 dogs (17%) had 2, 3 (17%) had 3, 1 (6%) had 4 and 1 (6%) had 5 organ dysfunctions. The median APPLEFAST score in the septic dogs was 28.5 (Q1-Q3, 24-31). Mean plasma concentrations of all endothelial and inflammatory biomarkers, except vWF, were higher in the sepsis cohort than in controls. The mean endothelial biomarker concentrations in the septic cohort ranged from ~2.7-fold higher for HA (difference in means; 118.2 ng/mL, 95% credible limit; 44.5-221.7) to ~150-fold for VEGF (difference in means; 76.6 pg./mL, 95% credible limit; 33.0-143.4), compared to the healthy cohort. Fifteen dogs with sepsis (83%) died; 7 (46%) were euthanized and 8 (53%) died during hospitalization. Conclusion: Dogs with naturally occurring sepsis and organ dysfunction had higher mean concentrations of biomarkers of endothelial activation and inflammation compared to healthy dogs, broadening our understanding of the pathophysiology of sepsis secondary to endothelial dysfunction.
PURPOSE: To investigate the effect of IV fluid resuscitation on endothelial glycocalyx (EG) shedding and activation of the vascular endothelium and inflammation. MATERIALS AND METHODS: A planned biomarker sub-study of the REFRESH trial in which emergency department (ED) patients) with suspected sepsis and hypotension were randomised to a restricted fluid/early vasopressor regimen or IV fluid resuscitation with later vasopressors if required (usual care). Blood samples were collected at randomisation (T0) and at 3 h (T3), 6 h (T6)- and 24 h (T24) for measurement of a range of biomarkers if EG shedding, endothelial cell activation and inflammation. RESULTS: Blood samples were obtained in 95 of 99 enrolled patients (46 usual care, 49 restricted fluid). Differences in the change in biomarker over time between the groups were observed for Hyaluronan (2.2-fold from T3 to T24, p = 0.03), SYN-4 (1.5-fold from T3 to T24, P = 0.01) and IL-6 (2.5-fold from T0 to T3, p = 0.03). No difference over time was observed between groups for the other biomarkers. CONCLUSIONS: A consistent signal across a range of biomarkers of EG shedding or of endothelial activation or inflammation was not demonstrated. This could be explained by pre-existing EG shedding or overlap between the fluid volumes administered in the two groups in this clinical trial. Trial registration Australia New Zealand Clinical Trials Registry ACTRN126160000006448 Registered 12 January 2016.
Red blood cell (RBC) transfusion is associated with recipient inflammation and infection, which may be triggered by excessive circulating iron. Iron chelation following transfusion may reduce these risks. The aim of this study was to evaluate the effect of deferoxamine on circulating iron and inflammation biomarkers over time and in vitro growth of Escherichia coli (E. coli) following RBC transfusion in dogs with atraumatic hemorrhage. Anesthetized dogs were subject to atraumatic hemorrhage and transfusion of RBCs, then randomized to receive either deferoxamine or saline placebo of equivalent volume (n = 10 per group) in a blinded fashion. Blood was sampled before hemorrhage and then 2, 4, and 6 h later. Following hemorrhage and RBC transfusion, free iron increased in all dogs over time (both p < 0.001). Inflammation biomarkers interleukin-6 (IL6), CXC motif chemokine-8 (CXCL8), interleukin-10 (IL10), and keratinocyte-derived chemokine (KC) increased in all dogs over time (all p < 0.001). Logarithmic growth of E. coli clones within blood collected 6 h post-transfusion was not different between groups. Only total iron-binding capacity was different between groups over time, being significantly increased in the deferoxamine group at 2 and 4 h post-transfusion (both p < 0.001). In summary, while free iron and inflammation biomarkers increased post-RBC transfusion, deferoxamine administration did not impact circulating free iron, inflammation biomarkers, or in vitro growth of E. coli when compared with placebo.
Synthetic colloid fluids containing hydroxyethyl starch (HES) have been associated with impairment of coagulation in dogs. It is unknown if HES causes coagulation impairment in dogs with naturally occurring critical illness. This study used banked plasma samples from a blinded, randomized clinical trial comparing HES and balanced isotonic crystalloid for bolus fluid therapy in 39 critically ill dogs. Blood was collected prior to fluid administration and 6, 12, and 24 h thereafter. Coagulation biomarkers measured at each time point included prothrombin time, activated partial thromboplastin time, thrombin time, fibrinogen concentration, and the activities of coagulation factors V, VII, VIII, IX, and X, von Willebrand factor antigen, antithrombin, and protein C. Given the links between coagulation and inflammation, cytokine concentrations were also measured, including interleukins 6, 8, 10, and 18, keratinocyte-derived chemokine, and monocyte chemoattractant protein-1. Data were analyzed with linear mixed effects models. No significant treatment-by-time interactions were found for any biomarker, indicating that the pattern of change over time was not modified by treatment. Examining the main effect of time showed significant changes in several coagulation biomarkers and keratinocyte-derived chemokines. This study could not detect evidence of coagulation impairment with HES.
Objectives: To compare concentrations of biomarkers of; allergy [mast cell tryptase (MCT) and histamine], inflammation [interleukin (IL)-6,-10, and-18, CXCL8, CCL2, keratinocyte chemoattractant (KC), C-reactive protein (CRP)], endothelial glycocalyx shedding (hyaluronan), coagulation [prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and von Willebrand Factor antigen, protein C (PC) and antithrombin (AT) activity], and hepatopathy [alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and total bilirubin] between dogs with anaphylaxis after suspected insect exposure, dogs with critical illness, and healthy dogs. Design: This was a single center prospective clinical observational comparative biomarker study that included 25 dogs with anaphylaxis (evidence of insect exposure, acute dermatological signs, and other organ involvement), 30 dogs with other critical illness, and 20 healthy dogs. Differences across groups in biomarker concentrations were tested using one-way ANOVA or Kruskal-Wallis test, with significant P values (<0.05) reported for pairwise differences detected by post-hoc tests. Logistic regression models were used to calculate the area under the receiver operator characteristic curve (AUROC) for discrimination between anaphylaxis and non-anaphylactic illness. Results: Histamine concentration was significantly higher in the anaphylaxis group than the healthy (P < 0.001) and critically ill groups (P < 0.001), whereas no differences in MCT were detected amongst groups. Biomarker concentrations that were increased relative to healthy dogs in both the anaphylaxis and critically ill groups included IL-10 (P < 0.001 and P = 0.007, respectively), CCL2 (P = 0.007 and P < 0.001, respectively) and AST (both P < 0.001), whereas only the critically ill group had significantly increased CRP (P < 0.001), IL-6 (P < 0.001), KC (P < 0.001), ALP (P < 0.001), and fibrinogen (P = 0.016) concentrations, compared to the healthy group. Only dogs with anaphylaxis had significantly higher hyaluronan (P = 0.021) and ALT (P = 0.021) concentrations, and lower PC (P = 0.030) and AT (P = 0.032) activities, compared to healthy dogs. Both CRP and histamine concentration showed good discrimination between anaphylaxis and other critical illness, with an AUROC of 0.96 (95% CI 0.91-1) and 0.81 (95% CI 0.69-0.93), respectively. Conclusions: This preliminary study in dogs with anaphylaxis after suspected insect exposure, found evidence of an early innate immune response, glycocalyx shedding and anticoagulant consumption. Both CRP and histamine showed potential clinical utility for differentiation between anaphylaxis and other critical illness.
BACKGROUND: Prestorage leukoreduction of red blood cell (RBC) bags prevents accumulation of pro-inflammatory mediators and experimentally attenuates post-transfusion inflammation in healthy dogs. However, the effect of leukoreduction on post-transfusion inflammation in critically ill dogs is unclear. HYPOTHESIS: Dogs transfused with leukoreduced (LR) RBC will have lower concentrations of leukocytes, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1), and C-reactive protein (CRP) within 24 hours of post-transfusion compared to dogs transfused with nonleukoreduced (NLR) RBC. ANIMALS: Sixty-one RBC-transfused dogs (LR = 34, NLR = 27). METHODS: Randomized, blinded, controlled preliminary clinical trial. Blood bag processing was randomized to create identically appearing LR and NLR bags. Group allocation occurred with transfusion of the oldest compatible RBC bag. Blood samples were collected pretransfusion and at 8 and 24 hours post-transfusion for leukocyte count, IL-6, IL-8, MCP-1, and CRP. Data were analyzed on an intention-to-treat basis using linear mixed effects models. Significance was set at P < .05. RESULTS: No significant differences were found between groups in concentrations of leukocytes (P = .93), IL-6 (P = .99), IL-8 (P = .75), MCP-1 (P = .69), or CRP (P = .18) over time. Eleven LR dogs (32%) and 4 NLR dogs (15%) were euthanized in the hospital (P = .14). No natural deaths occurred. CONCLUSIONS AND CLINICAL IMPORTANCE: No differences in inflammation biomarker concentrations were detected over time between dogs transfused with LR or NLR RBC, but heterogeneity likely hampered the ability to detect a difference with this sample size. The novel randomization and enrollment protocol was successfully implemented across 2 participating institutions and will be easily scaled up for a future multicenter clinical trial.
Dog Diseases , Erythrocyte Transfusion , Animals , Blood Preservation/veterinary , Critical Illness/therapy , Dog Diseases/therapy , Dogs , Erythrocyte Transfusion/veterinary , Inflammation/therapy , Inflammation/veterinary , Interleukin-6 , Interleukin-8
Endothelial glycocalyx (EG) shedding is associated with septic shock and described following intravenous (IV) fluid administration. To investigate the possible impact of IV fluids on the pathobiology of septic shock we investigated associations between biomarkers of EG shedding and endothelial cell activation, and relationships with IV fluid volume. Serum samples were obtained on admission (T0) and at 24 h (T24) in patients undergoing haemodynamic resuscitation for suspected septic shock in the emergency department. Biomarkers of EG shedding-Syndecan-1 (Syn-1), Syndecan-4 (Syn-4), Hyaluronan, endothelial activation-Endothelin-1 (ET-1), Angiopoeitin-2 (Ang-2), Vascular Endothelial Growth Factor Receptor-1(VEGF-1) and leucocyte activation/inflammation-Resistin, Neutrophil Gelatinase Associated Lipocalin (NGAL) and a marker of cardiac stretch-Pro-Atrial Natriuretic Peptide (Pro-ANP) were compared to the total IV fluid volume administered using Tobit regression. Data on 86 patients (52 male) with a mean age of 60 (SD 18) years were included. The mean fluid volume administered to T24 was 4038 ml (SD 2507 ml). No significant association between fluid volume and Pro-ANP or any of the biomarkers were observed. Syn-1 and Syn-4 were significantly correlated with each other (Spearman Rho 0.43, p < 0.001) but not with Hyaluronan. Syn-1 and Syn-4 both correlated with VEGFR-1 (Rho 0.56 and 0.57 respectively, p < 0.001) whereas Hyaluronan correlated with ET-1 (Rho 0.43, p < 0.001) and Ang-2 (Rho 0.43, p < 0.001). There was no correlation between Pro-ANP and any of the EG biomarkers. Distinct patterns of association between biomarkers of EG shedding and endothelial cell activation were observed among patients undergoing resuscitation for sepsis. No relationship between IV fluid volume and Pro-ANP or any of the other biomarkers was observed.
Sepsis , Shock, Septic , Atrial Natriuretic Factor/metabolism , Biomarkers , Emergency Service, Hospital , Glycocalyx/metabolism , Humans , Hyaluronic Acid/metabolism , Male , Middle Aged , Sepsis/metabolism , Shock, Septic/metabolism , Vascular Endothelial Growth Factor A/metabolism
BACKGROUND: There is no consensus on obtaining blood cultures routinely in companion animals with suspected sepsis, and there is a paucity of evidence concerning their utility. The objectives of this retrospective study were to determine the yield of positive blood cultures from hospitalized dogs, the prevalence of resistant bacteria, and the frequency and nature of changes to antimicrobial therapy once the culture result became available. KEY FINDINGS: Forty-five dogs had a blood culture submitted over a 10-year period, of which 9(20%) yielded positive growth and 36 (80%) yielded no bacterial growth. The most frequent reasons for submission of blood culture were pyrexia of unknown origin (n = 14), suspected soft tissue infection (7), and suspected discospondylitis (7). The most frequent final diagnoses were soft tissue infection (n = 11), discospondylitis (7), and unknown (6). No significant difference was found between the culture-positive versus culture-negative groups with regard to the most frequent reasons for blood culture (P = 0.55), final diagnoses (P = 0.80), survival until the blood culture result (P = 0.37), or whether the infection was hospital- or community-acquired (P = 0.99). There were significantly more immunosuppressed dogs in the culture-positive group (P = 0.02). Resistance to one or more antimicrobials was documented in all dogs with susceptibility reported. In the culture-positive dogs, 63% had antimicrobial de-escalation and none had escalation, whereas 19% of the culture-negative dogs had de-escalation and 7% had escalation. CONCLUSION: Blood cultures were submitted infrequently, but the proportion of resistance was higher than expected and supports the use of blood cultures in cases of suspected infection resulting in bacteremia.
Dog Diseases , Sepsis , Animals , Anti-Bacterial Agents/therapeutic use , Bacteria , Blood Culture/veterinary , Dog Diseases/diagnosis , Dog Diseases/drug therapy , Dogs , Retrospective Studies , Sepsis/veterinary
OBJECTIVE: The primary objective of this study was to document coagulation factor activity in canine "NEVER-FROZEN" and "THAWED" refrigerated plasma for the purposes of defining recommended expiration dates. We hypothesized that NEVER-FROZEN and THAWED refrigerated plasma would maintain >50% activity of coagulation factors V (FV), VII (FVII), VIII (FVIII), IX (FIX), X (FX), and von Willebrand factor antigen (vWF) and a concentration of fibrinogen above the lower bound of the reference interval (>0.982 g/L) for greater than 14 days but less than 42 days. DESIGN: Prospective laboratory-based study. SETTING: University teaching hospital blood bank. ANIMALS: Ten canine plasma units derived from healthy client-owned blood donors. INTERVENTIONS: Serial sampling (days 0, 1, 3, 5, 7, 10, 14, 17, 21, 24, 28, 32, 35, 39, 42) from NEVER-FROZEN and THAWED refrigerated canine plasma units was conducted for measurement of activities of FV, FVII, FVIII, FIX, FX, vWF, and fibrinogen concentrations using the ACL TOP 300. Plasma was defined as "suitable for transfusion" at a given time point if the entire 95% confidence interval for each factor was above 50% activity and above a fibrinogen concentration of 0.982 g/L. MEASUREMENTS AND MAIN RESULTS: The lower bounds of the FVIII and vWF confidence intervals were above 50% up to and including day 32 for NEVER-FROZEN refrigerated plasma and day 28 for THAWED refrigerated plasma. Confidence intervals for FV, FVII, FIX, and FX remained above 50% activity at all time points. The lower bound of the fibrinogen concentration was <0.982 g/L on day 39 for NEVER-FROZEN refrigerated plasma and on day 35 for THAWED refrigerated plasma. CONCLUSIONS: Refrigerated canine plasma from these 10 dogs retained coagulation factor activity above the limit that we defined as suitable for transfusion for up to 32 days when NEVER-FROZEN and 28 days when THAWED. Further studies should evaluate the clinical outcomes and effects on coagulation factor activity of dogs receiving refrigerated plasma transfusions.
Blood Coagulation Factors , Blood Preservation , Plasma , Animals , Blood Coagulation Factors/metabolism , Blood Preservation/veterinary , Dogs , Fibrinogen/metabolism , Freezing , Prospective Studies
BACKGROUND: Fluid resuscitation is frequently required for cardiac surgical patients admitted to the intensive care unit. The ideal fluid of choice in regard to efficacy and safety remains uncertain. Compared with crystalloid fluid, colloid fluid may result in less positive fluid balance. However, some synthetic colloids are associated with increased risk of acute kidney injury (AKI). This study compared the effects of succinylated gelatin (4%) (GEL) with compound sodium lactate (CSL) on urinary AKI biomarkers in patients after cardiac surgery. METHODS: Cardiac surgical patients who required an intravenous fluid bolus of at least 500 mL postoperatively were randomly allocated to receive GEL or CSL as the resuscitation fluid of choice for the subsequent 24 h. Primary outcomes were serial urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C concentrations measured at baseline, 1 h, 5 h and 24 h after enrolment, with higher concentrations indicating greater kidney injury. Secondary biomarker outcomes included urinary clusterin, α1-microglobulin and F2-isoprostanes concentrations. Differences in change of biomarker concentration between the two groups over time were compared with mixed-effects regression models. Statistical significance was set at P < 0.05. RESULTS: Forty cardiac surgical patients (n = 20 per group) with similar baseline characteristics were included. There was no significant difference in the median volume of fluid boluses administered over 24 h between the GEL (1250 mL, Q1-Q3 500-1750) and CSL group (1000 mL, Q1-Q3 500-1375) (P = 0.42). There was a significantly greater increase in urinary cystatin C (P < 0.001), clusterin (P < 0.001), α1-microglobulin (P < 0.001) and F2-isoprostanes (P = 0.020) concentrations over time in the GEL group, compared to the CSL group. Change in urinary NGAL concentration (P = 0.68) over time was not significantly different between the groups. The results were not modified by adjustment for either urinary osmolality or EuroSCORE II predicted risk of mortality. CONCLUSIONS: This preliminary randomised controlled trial showed that use of succinylated gelatin (4%) for fluid resuscitation after cardiac surgery was associated with increased biomarker concentrations of renal tubular injury and dysfunction, compared to crystalloid fluid. These results generate concern that use of intravenous gelatin fluid may contribute to clinically relevant postoperative AKI. Trial registration ANZCTR.org.au, ACTRN12617001461381. Registered on 16th October, 2017, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373619&isReview=true .
The goal of resuscitative fluid therapy is to rapidly expand circulating blood volume in order to restore tissue perfusion. Although this therapy often serves to improve macrohemodynamic parameters, it can be associated with adverse effects on the microcirculation and endothelium. The endothelial surface layer (ESL) provides a protective barrier over the endothelium and is important for regulating transvascular fluid movement, vasomotor tone, coagulation, and inflammation. Shedding or thinning of the ESL can promote interstitial edema and inflammation and may cause microcirculatory dysfunction. The pathophysiologic perturbations of critical illness and rapid, large-volume fluid therapy both cause shedding or thinning of the ESL. Research suggests that restricting the volume of crystalloid, or "clear" fluid, may preserve some ESL integrity and improve outcome based on animal experimental models and preliminary clinical trials in people. This narrative review critically evaluates the evidence for the detrimental effects of resuscitative fluid therapy on the ESL and provides suggestions for future research directions in this field.
Intravenous fluid administration in veterinary patients can alter coagulation function by several mechanisms. Both crystalloid and colloid fluids cause hemodilution, reducing platelet count and plasma coagulation protein concentrations. Hemodilution is associated with a hypercoagulable effect at low dilutions and a hypocoagulable effect at higher dilutions. Composition of crystalloid fluids likely has a minor effect, primarily dependent on fluid ion composition. Hypertonic crystalloids may also cause hypocoagulability. Colloids, both synthetic and natural, can cause hypocoagulability by several mechanisms beyond the effects of hemodilution. These include impaired platelet function, decreased plasma coagulation factor activity, impaired fibrin formation and crosslinking, and accelerated fibrinolysis. The vast majority of the veterinary literature investigates the hypocoagulable effects of hydroxyethyl starch-containing fluids using in vitro, experimental, and clinical studies. However, results are inconsistent, likely due to the varying doses and physicochemical properties of the specific fluid products across studies. In addition, some evidence exists for hypocoagulable effects of gelatin and albumin solutions. There is also evidence that these colloids increase the risk of clinical bleeding in people. Limitations of the veterinary evidence for the hypocoagulable effects of colloid fluids include a predominance of in vitro studies and in vivo studies using healthy subjects, which exclude the interaction of the effects of illness. Therefore, clinical relevance of these effects, especially for low-molecular-weight hydroxyethyl starch, is unknown. Firm recommendations about the most appropriate fluid to use in clinical scenarios cannot be made, although it is prudent to limit the dose of synthetic colloid in at-risk patients. Clinicians should closely monitor relevant coagulation assays and for evidence of hemorrhage in at-risk patients receiving any type of fluid therapy, especially in large volumes.
OBJECTIVE: To evaluate the effect of 6% hydroxyethyl starch (HES) 130/0.4, compared with a Hartmann's solution control (CRYST), on urine biomarkers of acute kidney injury (AKI) in dogs prescribed a fluid bolus. DESIGN: Randomized, controlled, blinded clinical trial January 2018 to February 2019. SETTING: University teaching hospital. ANIMALS: Forty client-owned dogs. INTERVENTIONS: Dogs prescribed a fluid bolus were randomized to receive at least 10 mL/kg of HES or CRYST with clinicians and investigators blinded to fluid type. Study fluid was used for further boluses as required in the following 24 hours, to a limit of 40 mL/kg total, after which fluid administration was open-label. MEASUREMENTS AND MAIN RESULTS: Urine was collected prior to and 6, 12, and 24 hours after the first study fluid bolus. Urine concentrations of AKI biomarkers: neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, kidney injury molecule-1 (KIM), clusterin, and osteopontin were measured using a magnetic bead multiplexed assay. Osmolality-indexed biomarker concentrations were compared between groups over time with linear mixed-effects models, with P < 0.05 considered significant. The mean volume of study fluid administered was not significantly different between groups (HES: 23.1 mL/kg, CRYST: 25.9 mL/kg; P = 0.47, t-test). There were no significant differences between groups in change over time of osmolality-indexed urine concentrations of NGAL (P = 0.91), cystatin C (P = 0.95), KIM (P = 0.77), clusterin (P = 0.63), or osteopontin (P = 0.91). The maximum Veterinary Acute Kidney Injury (VAKI) score up to 7 days during hospitalization (P = 1.0) and in-hospital mortality (P = 0.49) were not significantly different between groups, as compared by Fisher's exact test. CONCLUSIONS: There were no differences in change over time of urine AKI biomarkers in dogs treated with 10 - 40 mL/kg HES or CRYST over 24 hours. Larger clinical trials with patient-centered outcomes are required to investigate the safety of HES in dogs.
Acute Kidney Injury , Dog Diseases , Hydroxyethyl Starch Derivatives , Thymol , Animals , Dogs , Male , Acute Kidney Injury/chemically induced , Acute Kidney Injury/urine , Acute Kidney Injury/veterinary , Biomarkers/urine , Dog Diseases/chemically induced , Fluid Therapy/veterinary , Hydroxyethyl Starch Derivatives/adverse effects , Prospective Studies , Thymol/adverse effects
[This corrects the article DOI: 10.3389/fvets.2018.00279.].
Hepcidins are an evolutionarily conserved class of liver-expressed peptide, from which the twenty-five amino acid hormone, hepcidin-25 (herein hepcidin), has gained significant notoriety as the master regulator of iron homeostasis in mammals. Hepcidin maintains iron homeostasis by controlling the dietary absorption of iron and the mechanisms of recycling cellular iron stores. With the physiological significance of this hormone well established, it has emerged as an informative biomarker. In a comparison of the genome, transcriptome and peptidome of Canis lupis familiaris, we reveal the size of the hepcidin peptide in the canine, previous reports of which were contradictory to the evolutionary conservation predicted by genome annotation. Here, measurement of the peptide by mass spectrometry, following isolation from greyhound blood serum, revealed an amino acid sequence and peptide mass, differing from all accounts to date, yet demonstrating perfect sequence identity to that of the greater Canidae lineage of the Carnivora. Importantly, in the greyhound, the measured hepcidin peptide showed a similar temporal pattern to total serum iron, consistent with our understanding of hepcidin regulating iron homeostasis, in agreement with human diagnostics, and providing added translational evidence of the measured peptide being the iron regulatory hormone of the Canidae.
Evolution, Molecular , Hepcidins/genetics , Iron/metabolism , Amino Acid Sequence , Animals , Biomarkers/metabolism , Dogs , Hepcidins/metabolism , Homeostasis/genetics , Humans , Mammals
OBJECTIVE: To determine if low molecular weight synthetic colloid fluids administered to dogs interfere with refractometric estimates of total plasma protein (TPPr) and urine osmolality (UOsm). STUDY DESIGN: Experimental study. ANIMALS: Eighteen healthy Greyhound dogs. METHODS: Anaesthetized Greyhounds subjected to haemorrhage for 60 minutes were given 80 mL kg-1 of Plasma-Lyte 148 (CRYST), or 20 mL kg-1 of hydroxyethyl starch 130/0.4 (HES) or succinylated gelatine (GELO) (n = 6 per group) intravenously over 20 minutes. Refractometric (TPPr) and biuret total plasma protein (TPPb) were measured before haemorrhage (Baseline), at end of shock (Shock), immediately (T20), then 40 minutes (T60), 100 minutes (T120) and 160 minutes (T180) after fluid administration. Urine specific gravity (USG) and UOsm were measured at all time points except T20. Estimated UOsm (eUOsm) was calculated from USG. Bias and limits of agreement (LOA) for TPPr versus TPPb, and eUOsm versus UOsm were calculated at each time point. RESULTS: For dogs given CRYST and GELO, median TPPr and TPPb decreased in parallel, with a small consistent TPP bias (CRYST range of bias, 0.38-0.67 g dL-1; GELO range of bias, 0.42-0.58 g dL-1). Dogs given HES showed divergence between median TPPr and TPPb after T20, with a peak bias at T20 of 1.62 g dL-1 (LOA 1.29-1.95). Dogs given HES and GELO had markedly increased USG [HES peak median USG at T180 of 1.119 (Q1-Q3 1.103-1.122); GELO peak median USG at T120 of 1.114 (Q1-Q3 1.082-1.119)], with large increases in bias between eUOsm and UOsm [HES peak bias at T60 of 2995 mOsm kg-1 (LOA 2032-3958 mOsm kg-1); GELO peak bias at T120 of 2465 mOsm kg-1 (LOA 940-3990 mOsm kg-1)]. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of HES and GELO to dogs with haemorrhagic shock interferes with refractometric measurements for at least 3 hours after administration.
Dog Diseases/drug therapy , Gelatin/therapeutic use , Hydroxyethyl Starch Derivatives/therapeutic use , Shock, Hemorrhagic/veterinary , Succinates/therapeutic use , Animals , Dogs , Female , Fluid Therapy/veterinary , Gelatin/administration & dosage , Gelatin/pharmacology , Hydroxyethyl Starch Derivatives/administration & dosage , Hydroxyethyl Starch Derivatives/pharmacology , Male , Refractometry/veterinary , Shock, Hemorrhagic/drug therapy , Succinates/administration & dosage , Succinates/pharmacology , Urine/chemistry
OBJECTIVE AND DESIGN: Hypertonic saline administered during fluid resuscitation may mitigate endothelial glycocalyx (EG) shedding and inflammation. The objective of this pilot randomised controlled trial was to measure the effect of hypertonic saline, compared to isotonic saline, on biomarkers of EG shedding and inflammation in emergency department patients with suspected sepsis. METHODS: Patients received either 5â¯mL/kg of 3% saline (hypertonic group, nâ¯=â¯34) or 10â¯mL/kg of 0.9% saline (isotonic group, nâ¯=â¯31). Change in serum biomarker concentrations of syndecan-1, hyaluronan, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, interleukin-6, -8, -10, interferon-γ, neutrophil gelatinase-associated lipocalin and resistin were compared from baseline (T0) to after fluid (T1), 3â¯h (T3) and 12-24â¯h (T24) later, as was serum osmolality, using linear mixed effects models. RESULTS: The hypertonic group had significantly increased mean serum osmolality compared to the isotonic group at T1 (Pâ¯<â¯.001) and T3 (Pâ¯=â¯.004). Minor differences were found in some biomarker outcomes, including a decreased fold-change in syndecan-1 at T1 (Pâ¯=â¯.012) and in interleukin-10 at T24 (Pâ¯=â¯.006) in the isotonic group, compared to the hypertonic group. CONCLUSIONS: Although a single bolus of hypertonic saline increased serum osmolality, it did not reduce biomarkers of EG shedding or inflammation, compared to patients that received isotonic saline. TRIAL REGISTRATION: ANZCTR.org.au, ACTRN12611001021965, Registered on 23rd September 2011.
Glycocalyx/chemistry , Saline Solution, Hypertonic/pharmacology , Saline Solution/pharmacology , Sepsis/therapy , Adult , Biomarkers/blood , Emergency Service, Hospital , Female , Fluid Therapy , Humans , Inflammation , Male , Middle Aged , Osmolar Concentration , Pilot Projects , Sepsis/blood , Treatment Outcome
OBJECTIVE: To investigate the association between synthetic colloids and biomarkers of acute kidney injury (AKI) in dogs with hemorrhagic shock. DESIGN: Experimental interventional study. SETTING: University. ANIMALS: Twenty-four healthy ex-racing Greyhounds. INTERVENTIONS: Anesthetized Greyhounds subjected to hemorrhage for 60 min were resuscitated with 20 mL/kg of fresh whole blood (FWB), 6% hydroxyethyl starch (HES) 130/0.4, 4% succinylated gelatin (GELO), or 80 mL/kg of isotonic crystalloid (CRYST) over 20 min (n = 6 per treatment). Concentrations of biomarkers of AKI were measured at baseline, end of hemorrhage, and at 40 (T60), 100 (T120), and 160 (T180) min after fluid bolus. Biomarkers included neutrophil gelatinase-associated lipocalin in urine and serum (uNGAL; sNGAL), and urine cystatin C (uCYSC), kidney injury molecule-1 (uKIM), clusterin (uCLUST), osteopontin, gamma-glutamyl transferase, monocyte chemoattractant protein-1 (uMCP), interleukin-6, interleukin-8, protein (uPROT), hyaluronan, and F2 -isoprostanes. Renal histology was scored for tubular injury and microvesiculation. Biomarker fold-change from baseline was compared between groups using mixed effects models (Bonferroni-Holm corrected P<0.05). Frequencies of histology scores were compared by Fisher's exact test. MEASUREMENTS AND MAIN RESULTS: In dogs treated with GELO, uNGAL fold-change was markedly greater compared with all other groups at T60, T120, and T180 (all P<0.001), and uCYSC was greater at T60 compared with CRYST (P<0.001), and at T120 and T180 compared with all other groups (all P<0.001). Smaller, albeit significant, between-group differences in uKIM, uCLUST, uMCP, and urine protein concentration were observed across the FWB, GELO, and HES groups, compared with CRYST. The GELO group more frequently had marked tubular microvesiculation than the other groups (P = 0.015) although tubular injury scores were comparable. CONCLUSION: In dogs with hemorrhagic shock, GELO was associated with greater magnitude increases in urine biomarkers of AKI and more frequent marked tubular microvesiculation, compared with FWB, CRYST, and HES.
Acute Kidney Injury/veterinary , Biomarkers/urine , Dog Diseases/drug therapy , Lipocalin-2/urine , Shock, Hemorrhagic/veterinary , Acute Kidney Injury/chemically induced , Acute Kidney Injury/urine , Animals , Critical Care , Disease Models, Animal , Dogs , Female , Gelatin/administration & dosage , Gelatin/adverse effects , Hydroxyethyl Starch Derivatives/administration & dosage , Hydroxyethyl Starch Derivatives/adverse effects , Male , Plasma Substitutes/administration & dosage , Plasma Substitutes/adverse effects , Shock, Hemorrhagic/drug therapy , Succinates/administration & dosage , Succinates/adverse effects
Background: Hemorrhagic shock and volume replacement can alter coagulation. Synthetic colloids, hydroxyethyl starch (HES), and gelatin, may enhance hypocoagulability. Our primary objective was to describe the effect of four fluid products on coagulation in canine hemorrhagic shock. Our secondary objective was to compare measurements of coagulation during shock to baseline in all dogs. Methods: Anesthetized greyhounds subjected to atraumatic hemorrhage for 60 min were administered 20 mL kg-1 of either fresh whole blood (FWB), 6% HES 130/0.4, 4% succinylated gelatin (GELO), or 80 mL kg-1 of isotonic crystalloid over 20 min (n = 6 per group). Platelet closure time (PCT), rotational thromboelastometry (ROTEM) and plasma coagulation assays were measured at baseline, end of hemorrhage (shock), and 40 (T60), and 160 (T180) min after study fluid. ROTEM parameters included clotting time (CT), clot formation time (CFT), alpha angle, maximum clot firmness (MCF), lysis index at 60 min (LI60), and thrombodynamic potential index (TPI) for INTEM, EXTEM, FIBTEM (MCF only), and APTEM (LI60 only) profiles. Plasma coagulation assays included prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen concentration and activities of factor VII (FVII), factor VIII (FVIII), and von Willebrand Factor antigen (vWF). Between-group differences were tested using linear mixed models with post-hoc between-group comparisons (Bonferroni-Holm corrected). Differences between baseline and shock were tested using paired t-tests. Significance was set at P < 0.05. Results: GELO showed longer PCT at T60, compared with FWB and CRYST, and at T180, compared with all other groups. HES showed longer EXTEM CT at T60, compared with all other groups. HES showed lower INTEM and EXTEM MCF at T60 and lower INTEM MCF at T180, compared with FWB. Some plasma coagulation assays showed greater hypocoagulability with HES. Comparing shock to baseline, EXTEM CT, INTEM CFT, EXTEM CFT, PT, and FVIII significantly increased and PCT, INTEM CT, INTEM MCF, EXTEM MCF, EXTEM LI60, EXTEM TPI, FIBTEM MCF, APTT, fibrinogen, FVII, and vWF significantly decreased. Conclusions: In dogs with hemorrhagic shock, volume replacement with GELO caused mild platelet dysfunction and HES was associated with coagulation changes consistent with hypocoagulability, beyond effects of hemodilution. Shock alone produced some evidence of hypocoagulability.
