No-fluid Group Research Articles

Magnetic resonance imaging for relationship between the severity of perianchor fluid collection and rotator cuff integrity after arthroscopic double-row suture-bridge rotator cuff repair

PurposeThe primary purpose of this study was to assess perianchor fluid collection (PFC) severity of medial anchor and rotator cuff integrity association after arthroscopic double-row suture-bridge rotator cuff repair (RCR) and the secondary purpose was to identify the demographic and radiologic risk factors for high-grade PFC. HypothesisRe-tear rate would be significant higher in patients with high-grade PFC. MethodsWe retrospectively reviewed patients with arthroscopic double-row suture-bridge RCR for full-thickness rotator cuff tear (RCT) at our institution between February 2012 and May 2018. Based on the PFC severity, they were divided into the no-fluid (no fluid collection), low-grade (minimal or local fluid collection around the anchor), and high-grade (fluid collection beyond the entire length of the anchor) groups. Magnetic resonance imaging was performed 6 months postoperatively for assessing PFC severity and repaired rotator cuff integrity association, besides evaluating correlation between severity and various demographic and radiologic factors, including work level (low/medium/high) and RCT size. ResultsThis study included 312 patients, 181 (58%) in the no fluid group, 82 (26.3%) in the low-grade PFC group, and 49 (15.7%) in the high-grade PFC group. Re-tear occurred in 73 (23.4%) patients and was more frequent in the high-grade group (26/49 [53.1%]) than in the no-fluid (27/181 [14.9%]; p<0.001) and low-grade (20/82 [24.4%]; p=0.001) groups, without statistically significant differences between the latter two (p=0.082). Among the demographic factors, work level (low/medium/high) differed significantly between the no-fluid (22.1%/58.0%/19.9%), low-grade (25.7%/46.3%/28.0%), and high-grade (26.5%/34.7%/38.8%) groups (p=0.026). Among the radiologic factors, the mediolateral tear size differed significantly between the three groups (no-fluid group: 1.7±0.8cm, low-grade group: 1.8±0.6cm, high-grade group: 2.2±1.0cm; p=0.003). Multivariate regression analysis showed that mediolateral tear size (odds ratio: 1.821; 95% confidence interval: 1.258–2.636; p=0.001) was an independent risk factor for high-grade PFC. ConclusionsAfter arthroscopic double-row suture-bridge RCR, the highest re-tear rate was observed in patients with high-grade PFC, while there was no significant difference in rates between no-fluid and low-grade PFC groups. As PFC severity increased, the risk of re-tear increased. In particular, larger mediolateral tear size was associated with high-grade PFC. Level of evidenceIII; case-control study.

Plasma and Urinary Glycosaminoglycans as Evidence for Endotheliopathy in a Swine Burn Model

BackgroundThe endothelial glycocalyx controls vascular permeability, cellular signaling, blood-endothelial cell adhesion, extravasation, and transmission of shear stress signals. Burn injury compromises integrity of this layer increasing vascular permeability, which is further exacerbated by large volumes of (intravenous) crystalloids. We have shown that enteral resuscitation is able to reverse burn-induced acute kidney injury (AKI), and herein, we present a follow-up examination of the integrity of the glycocalyx layer and its relationship with renal dysfunction after burn injury. Materials and methodsAnesthetized Yorkshire pigs sustained 40% total body surface area full-thickness contact burns and recovered in metabolic cages for one of three treatments: no fluids (oral or intravenous); (n = 6), ad libitum water (n = 6), or volume-matched oral rehydration solution (ORS; n = 6) for 48 h. Urine and blood were collected at baseline (BL), 6, 12, 24, 32, and 48 h after burn at which point kidneys were harvested. ResultsIn no fluid and water groups (but not ORS), plasma levels of glycosaminoglycans (GAGs) were elevated after burn (P ≤ 0.031). Syndecan-1 was elevated by 6 h after burn in all animals, but levels declined by 24 h with enteral fluids. Urinary GAGs in the no-fluid group were elevated after burn. No differences among treatments were detected in syndecan-1 levels, or glomerular lectin within the kidney. ConclusionsCollectively, these data demonstrate that ORS prevented increases in circulating GAGs. Furthermore, an inexpensive and simple method for detecting GAGs provides a sensitive measure of endotheliopathy after burn.

Tissue Inflammatory Markers and Oxidative Stress in Swine Subjected to a 40% TBSA Burn Injury

Burn injury is well known to induce a robust inflammatory response and hypermetabolic state. Intravenous (IV) crystalloid fluid resuscitation of burn patients is the foundation of modern burn care to improve tissue perfusion and outcomes. However, under military scenarios of far‐forward burn care or under civilian mass casualty situations, the availability of large volumes of such fluids for IV burn resuscitation will be logistically challenging and definitive burn care may be delayed for days. More recently, enteral resuscitation of burns has received renewed attention and some evidence suggests that it may reduce IV fluid requirements to support urine output. The present study investigated the early response of tissue inflammatory markers and evidence for oxidative stress in swine subjected to a 40% burn and resuscitated with enteral fluids compared to no fluids or a standard of care IV fluid regimen. Anesthetized Yorkshire swine (n=6 per group) were subjected to a 40% full thickness total body surface area (TBSA) burn with brass probes heated to 100°C. They were then randomized to 4 groups: 1) no fluid (NF), 2) 15 ml/kg/d WHO oral rehydration solution (ORS) (15‐ORS), 3) 70 ml/kg ORS (70‐ORS) or 4) 2 ml/kg/% burn IV lactated Ringer's (Modified Brooke (MB) formula‐ a standard of care). After 48 h, animals were euthanized and heart, liver, kidney, lung and small intestine collected and analyzed for tissue cytokine levels and indices of oxidative stress. As expected, urine output was higher in the 70‐ORS and MB groups than the NF group (p&lt;0.01). Although plasma creatinine and BUN peaked 6 h after burn, levels returned to baseline by 48 h in all groups except 15‐ORS and NF. In the kidney, levels of IL‐1β, IL‐6 and TNF‐α tended to be higher in the 70‐ORS and MB groups, whereas IL‐10 levels were similar among groups. In liver, heart and jejunum, only IL‐1β levels tended to be higher in MB than the other groups, with a similar trend in IL‐10 concentrations. With regard to oxidant status in kidney, total antioxidant levels, glutathione reductase (GR) and glutathione peroxidase activities were higher in 70‐ORS than the other groups. Mn‐superoxide dismutase (SOD) activity was higher in both 70‐ORS and MB groups, with no differences in catalase activity or nitric oxide levels. In liver, the lowest levels of total antioxidants, SOD, GR and catalase activities were observed in the NF groups compared to the others. No significant differences in indices of antioxidant status were observed in jejunum, heart or lung among groups. Typically, these variables in 15‐ORS were similar to the NF group in all tissues. The results of this study indicate that enteral fluids may be as effective as a standard of care IV fluid regimen in maintaining antioxidant status in vital organs without major changes in pro‐inflammatory cytokines. As such, this oral resuscitation may prove lifesaving in resource poor environments and reduce potential IVfluid‐related complications until definitive clinical care is available.Support or Funding InformationFunded by US Army MRMCThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Hypertonic Sodium Chloride Preinjectate Increases In Vivo Radiofrequency Ablation Size: Histological and Magnetic Resonance Imaging Findings.

Emphasis has been placed on methods to enlarge monopolar radiofrequency (RF) lesion size for pain management. Ex vivo research has suggested that fluid modulation may be an effective method to enlarge lesion zone. To date, these findings have not been confirmed in vivo. The purpose of this study was to determine the effect of hypertonic saline on in vivo lesion size through both histological and magnetic resonance imaging (MRI) analysis. A secondary purpose was to validate in vivo characterization of RF lesions using contrast-enhanced MRI. Monopolar RF was performed in an in vivo porcine model in 3 groups: (1) without fluid preinjection, (2) with preinjection of 1% lidocaine, or (3) with preinjection of 1% lidocaine and 8% sodium chloride. Following lesioning, MRI processing with gadolinium-enhanced, T1-weighted imaging and histological analysis was performed. The addition of 8% sodium chloride significantly increased the size of RF lesion in comparison to the addition of 1% lidocaine alone and to the absence of fluid injection, as assessed by histological and MRI analysis. Three distinct histological lesion zones were identified. In comparison to the no-fluid group, the addition of hypertonic saline significantly altered the shape and histological composition of the lesion. There was a significant correlation of lesion volume as assessed by MRI and by histology measurements. Peak power and total energy delivery also correlated with lesion size. This study validates the ability of hypertonic saline to increase in vivo RF lesion size. With further refinement, MRI may be a viable method to assess RF lesion size.

Water balance during parturition and early puerperium: A prospective open trial

ObjectivesTo investigate how water balance is regulated during labor and 27h postpartum. Design and methodsA prospective open trial with 49 women giving birth vaginally. Ringer-acetate was infused intravenously and combined with epidural analgesia in seven women (fluid group). Intravenous infusions of oxytocin in 5% glucose were given to 12 women (oxytocin group). Thirty women delivered their babies without infusion (nofluid group). Blood and urine samples were collected at arrival, at early stage 1, at early stage 2, and at aftercare, and 9, 15, and 27h postpartum. Plasma osmolality, sodium, cystatin C, vasopressin, oxytocin, urine flow, urine osmolality, and urine sodium were measued. ResultsThe oxytocin group had significantly lower plasma osmolality than the nofluid group before parturition, and they had lower plasma sodium concentration at early stage 1 and 2. Plasma vasopressin concentration was low and did not differ between groups or before and after parturition. Water diuresis developed postpartum in all groups. The cystatin C concentration decreased significantly after parturition in the oxytocin and nofluid groups. ConclusionsThe vasopressin levels were suppressed during parturition irrespective of the P-osmolality and the nongravid regulation of water balance had not returned within 27h postpartum.

Thermoregulation and Stress Hormone Recovery After Exercise Dehydration: Comparison of Rehydration Methods

Athletic trainers recommend and use a multitude of rehydration (REHY) methods with their patients. The REHY modality that most effectively facilitates recovery is unknown. To compare 5 common REHY methods for thermoregulatory and stress hormone recovery after exercise dehydration (EXDE) in trained participants. Randomized, cross-over, controlled study. Twelve physically active, non-heat-acclimatized men (age = 23 ± 4 years, height = 180 ± 6 cm, mass = 81.3 ± 3.7 kg, VO2max = 56.9 ± 4.4 mL·min(-1)·kg(-1), body fat = 7.9% ± 3%) participated. Participants completed 20-hour fluid restriction and 2-hour EXDE; they then received no fluid (NF) or REHY (half-normal saline) via ad libitum (AL), oral (OR), intravenous (IV), or combination IV and OR (IV + OR) routes for 30 minutes; and then were observed for another 30 minutes. Body mass, rectal temperature, 4-site mean weighted skin temperature, plasma stress hormone concentrations, and environmental symptoms questionnaire (ESQ) score. Participants were hypohydrated (body mass -4.23% ± 0.22%) post-EXDE. Rectal temperature for the NF group was significantly greater than for the IV group (P = .023) at 30 minutes after beginning REHY (REHY30) and greater than OR, IV, and IV + OR (P ≤ .009) but not AL (P = .068) at REHY60. Mean weighted skin temperature during AL was less than during IV + OR at REHY5 (P = .019). The AL participants demonstrated increased plasma cortisol concentrations compared with IV + OR, independent of time (P = .015). No differences existed between catecholamine concentrations across treatments (P > .05). The ESQ score was increased at REHY60 for NF, AL, OR, and IV (P < .05) but not for IV + OR (P = .217). The NF ESQ score was greater than that of IV + OR at REHY60 (P = .012). Combination IV + OR REHY reduced body temperature to a greater degree than OR and AL REHY when compared with NF. Future studies addressing clinical implications are needed.

Uncontrolled hemorrhagic shock results in a hypercoagulable state modulated by initial fluid resuscitation regimens

Previous studies have shown large-volume resuscitation modulates coagulopathy and inflammation. Our objective was to analyze the effects of initial bolus fluids used in military and civilian settings on coagulation and inflammation in a prospective, randomized, blinded trial of resuscitation of uncontrolled hemorrhage. Fifty swine were anesthetized, intubated, and ventilated and had monitoring lines placed. A Grade V liver injury was performed followed by 30 minutes of hemorrhage. After 30 minutes, the liver was packed, and randomized fluid resuscitation was initiated during a 12-minute period with 2 L of normal saline, 2 L of lactated Ringer's solution, 250 mL of 7.5% saline with 3% Dextran, 500 mL of Hextend, or no fluid (NF). Animals were monitored for 2 hours after injury. Thrombelastograms (TEGs), prothrombin time (PT), partial thromboplastin time, fibrinogen as well as serum interleukin 6, interleukin 8, and tumor necrosis factor α levels were drawn at baseline and after 1 hour and 2 hours. The NF group had less posttreatment blood loss compared with other groups (p < 0.01). Blood loss was similar in the other groups. TEG R values in each group decreased from baseline at 1 and 2 hours (p < 0.02). The groups receiving 2 L of normal saline, 250 mL of 7.5% saline with 3% Dextran, or 500 mL of Hextend had lower TEG maximum amplitude values compared with NF group (p < 0.02). All fluids except lactated Ringer's solution resulted in significant increases in PT compared with NF, whereas all fluids resulted in significant decreases in fibrinogen compared with NF (p < 0.02). Fluid resuscitation groups as well as NF group demonstrated significant increases in inflammatory cytokines from baseline to 1 hour and baseline to 2 hours. There were no significant differences in inflammatory cytokines between groups at 2 hours. Withholding fluid resulted in the least significant change in PT, fibrinogen, and maximum amplitude and in the lowest posttreatment blood loss. Resuscitation with different initial fluid resuscitation strategies did not result in increased proinflammatory mediators compared with animals that did not receive fluid.

Permissive hypotension does not reduce regional organ perfusion compared to normotensive resuscitation: animal study with fluorescent microspheres

IntroductionThe objective of this study was to investigate regional organ perfusion acutely following uncontrolled hemorrhage in an animal model that simulates a penetrating vascular injury and accounts for prehospital times in urban trauma. We set forth to determine if hypotensive resuscitation (permissive hypotension) would result in equivalent organ perfusion compared to normotensive resuscitation.MethodsTwenty four (n=24) male rats randomized to 4 groups: Sham, No Fluid (NF), Permissive Hypotension (PH) (60% of baseline mean arterial pressure - MAP), Normotensive Resuscitation (NBP). Uncontrolled hemorrhage caused by a standardised injury to the abdominal aorta; MAP was monitored continuously and lactated Ringer’s was infused. Fluorimeter readings of regional blood flow of the brain, heart, lung, kidney, liver, and bowel were obtained at baseline and 85 minutes after hemorrhage, as well as, cardiac output, lactic acid, and laboratory tests; intra-abdominal blood loss was assessed. Analysis of variance was used for comparison.ResultsIntra-abdominal blood loss was higher in NBP group, as well as, lower hematocrit and hemoglobin levels. No statistical differences in perfusion of any organ between PH and NBP groups. No statistical difference in cardiac output between PH and NBP groups, as well as, in lactic acid levels between PH and NBP. NF group had significantly higher lactic acidosis and had significantly lower organ perfusion.ConclusionsHypotensive resuscitation causes less intra-abdominal bleeding than normotensive resuscitation and concurrently maintains equivalent organ perfusion. No fluid resuscitation reduces intra-abdominal bleeding but also significantly reduces organ perfusion.

Influence of crystalloid and colloid fluid infusion and blood withdrawal on pulmonary bioimpedance in an animal model of mechanical ventilation

Electrical impedance tomography (EIT) is considered useful for monitoring regional ventilation and aeration in intensive-care patients during mechanical ventilation. Changes in their body fluid state modify the electrical properties of lung tissue and may interfere with the EIT measurements of lung aeration. The aim of our study was to assess the effects of crystalloid and colloid infusion and blood withdrawal on bioimpedance determined by EIT in a chest cross-section. Fourteen anaesthetized mechanically ventilated pigs were subjected to interventions affecting the volume state (crystalloid and colloid infusion, blood withdrawal). Six animals received additional crystalloid fluids (fluid group) whereas eight did not (no-fluid group). Global and regional relative impedance changes (RIC, dimensionless unit) were determined by backprojection at end-expiration. Regional ventilation distribution was analyzed by calculating the tidal RIC in the same regions. Colloid infusion led to a significant fall in the global end-expiratory RIC (mean differences: fluid: −91.2, p < 0.001, no-fluid: −38.9, p < 0.001), which was partially reversed after blood withdrawal (mean differences, fluid: +45.1, p = 0.047 and no-fluid: +26.2, p = 0.009). The RIC was significantly lower in the animals with additional crystalloids (mean group difference: 45.5, p < 0.001). Global and regional tidal volumes were not significantly affected by the fluid and volume states.

Hemodynamics of anesthetized ventilated mouse models: aspects of anesthetics, fluid support, and strain.

This study evaluates the effects of anesthesia and fluid support on hemodynamic parameters of the mechanically ventilated mouse of four different strains. All experiments were performed at a similar surgical level of anesthesia, as indicated by the probing of the pedal withdrawal reflex. Three anesthetic regimens [fentanyl-fluanisone-midazolam (FFM), ketamine-medetomidine-atropine (KMA), and isoflurane (ISO)], four commonly used mouse strains (Swiss, CD-1, BalbC, and C57Bl6), and three different fluid support strategies (no fluid, 0.2 ml x h(-1) x 10 g(-1) of 6% polystarch solution, and 0.5 ml x h(-1) x 10 g(-1) saline) were studied. Mean arterial pressure (MAP) or heart rate (HR) was similar among the four strains of mice except a trend toward lower HR for the BalbC mice. In terms of MAP, KMA is the preferred anesthetic for the Swiss and CD-1 mice, whereas KMA or ISO are recommended for BalbC or C57Bl6 mice. In terms of HR, ISO is the preferred anesthetic for the Swiss, CD-1, and C57Bl6 strains. No differences in HR for the three anesthetics were observed for the BalbC strain. Compared with administration of no fluid, both saline and polystarch administration similarly increased MAP by 7 +/- 2, 10 +/- 2, and 11 +/- 2 mmHg at t = 1, 2, and 3 h, respectively, whereas fluid administration was without effect on HR. Saline supplementation resulted in an increased dry-to-wet ratio of the heart and both fluid regimens decreased total hemoglobin in the blood from 12.6 +/- 0.5 to 10.4 +/- 0.5 g/100 ml. Saline administration was associated with blood acidosis (pH 7.20 +/- 0.03) compared with the Haes (pH 7.29 +/- 0.02) or no-fluid group (pH 7.34 +/- 0.03), whereas PCO(2) was approximately 30 mmHg for all groups. We conclude that at similar surgical levels of anesthesia, the preferable type of anesthesia (ISO or KMA, but never FFM) depends on the strain used and whether MAP or HR is the focus of study. Additional fluid support is beneficial in terms of raising arterial blood pressure, although this is at the cost of changes in organ water content and increased anemia.

Effect of Immediate Fluid Resuscitation on the Rate, Volume, and Duration of Pulmonary Vascular Hemorrhage in a Sheep Model of Penetrating Thoracic Trauma

Study objective: To determine the effects of early fluid resuscitation on the rate, volume, and duration of hemorrhage using a sheep model of uncontrolled pulmonary vascular hemorrhage. Methods: Sixteen adult sheep were anesthetized and fitted with catheters to measure systemic and pulmonary artery pressures. A branch of the pulmonary vein was then lacerated through an anterolateral thoracotomy, and a chest tube was inserted to monitor hemorrhage volume. Eight animals were assigned to the immediate fluid (IF) resuscitation group and were given 30 mL/kg of lactated Ringer's solution over a period of 10 minutes; this treatment was repeated once if normotension was not achieved. The other eight animals received no fluid (NF) and served as nonresuscitated controls. Results: The IF animals had a mean hemorrhage volume of 3,494±1,525 mL, compared with 1,594±689 mL in the NF group ( P<.001). Hemorrhage stopped spontaneously in the NF group at a mean of 29±9 minutes but took 48±11 minutes in the IF group ( P=.003). During the 20-minute period of fluid resuscitation, the IF animals bled at twice the rate of the NF animals (90±33 versus 46±22 mL/minute, respectively; P=.02). During the 10-minute interval after fluids were administered, the rate of hemorrhage remained brisk at 73±57 mL/minute in the IF group but virtually stopped in the NF group (6±7 mL/minute; P=.02). Conclusion: In this sheep model of uncontrolled pulmonary vascular hemorrhage, immediate fluid resuscitation significantly increased the rate, volume, and duration of hemorrhage. The vigorous administration of fluids to patients with penetrating chest trauma has the potential to significantly increase blood loss. [Sakles JC, Sena MJ, Knight DA, Davis JM: Effect of immediate fluid resuscitation on the rate, volume, and duration of pulmonary vascular hemorrhage in a sheep model of penetrating thoracic trauma. Ann Emerg Med March 1997;29:392-399.]