Intravenous administration of mesenchymal stromal cells leads to a dose-dependent coagulopathy and is unable to attenuate acute traumatic coagulopathy in rats

BACKGROUND

Mesenchymal stromal cells (MSCs) express surface tissue factor (TF), which may affect hemostasis and detract from therapeutic outcomes of MSCs if administered intravenously. In this study, we determine a safe dose of MSCs for intravenous (IV) administration and further demonstrate the impact of IV-MSC on acute traumatic coagulopathy (ATC) in rats.

METHODS

Tissue factor expression of rat bone marrow-derived mesenchymal stromal cell (BMSC) or adipose-derived mesenchymal stromal cell (AMSC) was detected by immunohistochemistry and enzyme-linked immunosorbent assay. The coagulation properties were measured in MSC-treated rat whole blood, and blood samples were collected from rats after IV administration of MSCs. Acute traumatic coagulopathy rats underwent polytrauma and 40% hemorrhage, followed by IV administration of 5 or 10 million/kg BMSCs (BMSC-5, BMSC-10), or vehicle at 1 hour after trauma.

RESULTS

Rat MSCs expressed TF, and incubation of rat BMSCs or AMSCs with whole blood in vitro led to a significantly shortened clotting time. However, a dose-dependent prolongation of prothrombin time with reduction in platelet counts and fibrinogen was found in healthy rat treated with IV-MSCs. Bone marrow-derived mesenchymal stromal cells at 5 million/kg or less led to minimal effect on hemostasis. Mesenchymal stromal cells were not found in circulation but in the lungs after IV administration regardless of the dosage. Acute traumatic coagulopathy with prolonged prothrombin time was not significantly affected by 5 or 10 million/kg BMSCs. Intravenous administration of 10 million/kg BMSCs led to significantly lower fibrinogen and platelet counts, while significantly higher levels of lactate, wet/dry weight ratio, and leukocyte infiltration in the lung were present compared with BMSC-5 or vehicle. No differences were seen in immune or inflammatory profiles with BMSC treatment in ATC rats, at least in the acute timeframe.

CONCLUSION

Intravenous administration of MSCs leads to a risk of coagulopathy associated with a dose-dependent reduction in platelet counts and fibrinogen and is incapable of restoring hemostasis of rats with ATC after polytrauma and hemorrhagic shock.

Acute intensive care unit resuscitation of severely injured trauma patients: Do we need a new strategy?

BACKGROUND

Unlike recent advances in blood product resuscitation, intravenous crystalloid (IVF) use after intensive care unit (ICU) admission in hemorrhagic shock has received less attention and current recommendations are based on limited evidence. To address this knowledge gap, we aimed to determine associations between IVF administration during acute ICU resuscitation and outcomes. We hypothesized that larger IVF volumes are associated with worse outcomes.

METHODS

We linked our trauma registry with electronic health record data (2012-2015) to identify adults with an initial lactate level of ≥4 mmol/L and documented lactate normalization (≤2 mmol/L), excluding those with isolated head Abbreviated Injury Scale score ≥3. We focused on the period from ICU admission to lactate normalization, analyzing duration, volume of IVF, and proportion of volume as 1-L boluses. We used linear regression to determine associations with ICU length of stay and duration of mechanical ventilation in survivors, and logistic regression to identify associations with acute kidney injury and home discharge while adjusting for important covariates.

RESULTS

We included 337 subjects. Median time to lactate normalization was 15 hours (interquartile range, 7-25 hours), and median IVF volume was 3.7 L (interquartile range, 1.5-6.4 L). The fourfold difference between the upper and lower quartiles of both duration and volume remained after stratifying by injury severity. Hourly volumes tapered over time but persistently aggregated at 0.5 and 1 L, with 167 subjects receiving at least one 0.5-L bolus for 6 hours after ICU admission. Administration of larger volumes was associated with longer ICU length of stay and duration of mechanical ventilation, as well as acute kidney injury.

CONCLUSION

There is substantial variation in volume administered during acute ICU resuscitation, both absolutely and temporally, despite accounting for injury severity. Administration of larger volumes during acute ICU resuscitation is associated with worse outcomes. There is an opportunity to improve outcomes by further investigating and standardizing this important phase of care.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Identification of unique microRNA expression patterns in bone marrow hematopoietic stem and progenitor cells after hemorrhagic shock and multiple injuries in young and old adult mice

BACKGROUND

After severe trauma, the older host experiences more dysfunctional hematopoiesis of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs), and dysfunctional differentiation of circulating myeloid cells into effective innate immune cells. Our main objective was to compare BM HSPC microRNA (miR) responses of old and young mice in a clinically relevant model of severe trauma and shock.

METHODS

C57BL/6 adult male mice aged 8 to 12 weeks (young) and 18 to 24 months (old) underwent multiple injuries and hemorrhagic shock (polytrauma [PT]) that engenders the equivalent of major trauma (Injury Severity Score, >15). Pseudomonas pneumonia (PNA) was induced in some young and old adult mice 24 hours after PT. MicroRNA expression patterns were determined from lineage-negative enriched BM HSPCs isolated from PT and PT-PNA mice at 24 and 48 hours postinjury, respectively. Genome-wide expression and pathway analyses were also performed on bronchoalveolar lavage (BAL) leukocytes from both mouse cohorts.

RESULTS

MicroRNA expression significantly differed among all experimental conditions (p < 0.05), except for old-naive versus old-injured (PT or PT-PNA) mice, suggesting an inability of old mice to mount a robust early miR response to severe shock and injury. In addition, young adult mice had significantly more leukocytes obtained from their BAL, and there were greater numbers of polymorphonuclear cells compared with old mice (59.8% vs. 2.2%, p = 0.0069). Despite increased gene expression changes, BAL leukocytes from old mice demonstrated a more dysfunctional transcriptomic response to PT-PNA than young adult murine BAL leukocytes, as reflected in predicted upstream functional pathway analysis.

CONCLUSION

The miR expression pattern in BM HSPCs after PT (+/-PNA) is dissimilar in old versus young adult mice. In the acute postinjury phase, old adult mice are unable to mount a robust miR HSPC response. Hematopoietic stem and progenitor cell miR expression in old PT mice reflects a diminished functional status and a blunted capacity for terminal differentiation of myeloid cells.

Critical traumatic brain injury is associated with worse coagulopathy

OBJECTIVES

As thromboelastography (TEG) becomes the standard of care in patients with hemorrhagic shock (HS), an association between concomitant traumatic brain injury (TBI) and coagulopathy by TEG parameters is not well understood and is thus investigated.

METHODS

Retrospective analysis of trauma registry data at a single level 1 trauma center of 772 patients admitted with head Abbreviated Injury Scale (AIS) score of 3 and TEG studies between 2014 and 2017. Patients were stratified to moderate-severe TBI by head AIS scores of 3 and 4 (435 patients) and critical TBI by head AIS score of 5 (328 patients). Hemorrhagic shock was defined by base deficit of 4 or shock index of 0.9. Statistical analysis with unpaired t tests compared patients with critical TBI with patients with moderate-severe TBI, and patients were grouped by presence or absence of HS. A comparison of TBI data with conventional coagulation studies was also evaluated.

RESULTS

In the setting of HS, critical TBI versus moderate-severe TBI was associated with longer R time (p = 0.004), longer K time (p < 0.05), less acute angle (p = 0.001), and lower clot strength and stability (maximum amplitude [MA]) (p = 0.01). Worse TBI did not correlate with increased fibrinolysis by clot lysis measured by the percentage decrease in amplitude at 30 minutes after MA (p = 0.3). Prothrombin time and international normalized ratio failed to demonstrate more severe coagulopathy, while partial thromboplastin time was found to correlate with severity of TBI (p = 0.01). In patients with critical TBI, the presence of HS correlated with a statistically significant worsening of all parameters (p < 0.05) except for clot lysis measured by the percentage decrease in amplitude at 30 minutes after MA (LY-30).

CONCLUSION

Thromboelastography demonstrates that, with and without hemorrhagic shock, critical TBI correlates with a significant worsening of traumatic coagulopathy in comparison with moderate/severe TBI. In HS, critical TBI correlates with impaired clot initiation, impaired clot kinetics, and impaired platelet-associated clot strength and stability versus parameters found in moderate-severe TBI. Hemorrhagic shock correlates with worse traumatic coagulopathy in all evaluated patient groups with TBI. Conventional coagulation studies underestimate TBI-associated coagulopathy. Traumatic brain injury-associated coagulopathy is not associated with fibrinolysis.

LEVEL OF EVIDENCE

Prognostic/epidemiological, level IV; prognostic/epidemiological, level III.

Lactate as a mediator of prehospital plasma mortality reduction in hemorrhagic shock

BACKGROUND

Prehospital plasma transfusion in trauma reduces mortality. However, the underlying mechanism remains unclear. Reduction in shock severity may play a role. Lactate correlates with physiologic shock severity and mortality after injury. Our objective was to determine if prehospital plasma reduces lactate and if this contributes to the mortality benefit of plasma.

METHODS

Patients in the Prehospital Air Medical Plasma trial in the upper quartile of injury severity (Injury Severity Score, >30) were included to capture severe shock. Trial patients were randomized to prehospital plasma or standard care resuscitation (crystalloid ± packed red blood cells). Regression determined the associations between admission lactate, 30-day mortality, and plasma while adjusting for demographics, prehospital crystalloid, time, mechanism, and injury characteristics. Causal mediation analysis determined what proportion of the effect of plasma on mortality is mediated by lactate reduction.

RESULTS

A total of 125 patients were included. The plasma group had a lower adjusted admission lactate than standard of care group (coefficient, -1.64; 95% confidence interval [CI], -2.96 to -0.31; p = 0.02). Plasma was associated with lower odds of 30-day mortality (odds ratio [OR], 0.27; 95% CI, 0.08-0.90; p = 0.03). When adding lactate to this model, the effect of plasma on 30-day mortality was no longer significant (OR, 0.36; 95% CI, 0.07-1.88; p = 0.23), while lactate was associated with mortality (OR, 1.74 per 1 mmol/L increase; 95% CI, 1.10-2.73; p = 0.01). Causal mediation demonstrated 35.1% of the total effect of plasma on 30-day mortality was mediated by the reduction in lactate among plasma patients.

CONCLUSION

Prehospital plasma is associated with reduced 30-day mortality and lactate in severely injured patients. More than one third of the effect of plasma on mortality is mediated by a reduction in lactate. Thus, reducing the severity of hemorrhagic shock appears to be one mechanism of prehospital plasma benefit. Further study should elucidate other mechanisms and if a dose response exists.

LEVEL OF EVIDENCE

Therapeutic, level II.

Admission Lactate and Base Deficit in Predicting Outcomes of Pediatric Trauma

BACKGROUND

To compare admission lactate and base deficit (BD), which physiologically reflect early hemorrhagic shock, as outcome predictors of pediatric trauma.

METHODS

We reviewed the data of children with trauma who visited a Korean academic hospital from 2010 through 2018. Admission lactate and BD were compared between children with and without primary outcomes. The outcomes included in-hospital mortality, early (≤24 h) transfusion, and early surgical interventions for the torso or major vessels. Subsequently, performances of lactate and BD in predicting the outcomes were compared using receiver operating characteristic curves. Logistic regressions were conducted to identify the independent associations of the two markers with each outcome.

RESULTS

Of the 545 enrolled children, the mortality, transfusion, and surgical interventions occurred in 7.0%, 43.5%, and 14.9%, respectively. Cutoffs of lactate and BD for each outcome were as follows: mortality, 5.1 and 6.7 mmol/L; transfusion, 3.2 and 4.9 mmol/L; and surgical interventions, 2.9 and 5.2 mmol/L, respectively. No significant differences were found in the areas under the curve for each outcome. Of the two markers, a lactate of >5.1 mmol/L was associated with mortality (adjusted odds ratio, 6.43; 95% confidence interval, 2.61-15.84). A lactate of >3.2 mmol/L (2.82; 1.65-4.83) and a BD of >4.9 mmol/L (2.32; 1.32-4.10) were associated with transfusion, while only a BD of >5.2 mmol/L (2.17; 1.26-3.75) was done with surgical interventions.

CONCLUSIONS

In pediatric trauma, lactate is more strongly associated with mortality. In contrast, BD may have a marginally stronger association with the need for hemorrhage-related procedures.

Thrombin Generation Kinetics are Predictive of Rapid Transfusion in Trauma Patients Meeting Critical Administration Threshold

INTRODUCTION

We hypothesize that a patient (pt) with accelerated thrombin generation, time to peak height (ttPeak), will have a greater odds of meeting critical administration threshold (CAT) criteria (> 3 packed red blood cell [pRBC] transfusions [Tx] per 60 min interval), within the first 24 h after injury, independent of international normalized ratio (INR).

METHODS

In a prospective cohort study, trauma patients were enrolled over a 4.5-year period and serial blood samples collected at various time points. We retrospectively stratified pts into three categories: CAT+, CAT- but receiving some pRBC Tx, receiving no Tx within the first 24 h. Blood collected prior to Tx was analyzed for thrombin generation parameters and prothrombin time (PT)/INR.

RESULTS

A total of 484 trauma pts were analyzed: injury severity score = 13 [7,22], age = 48 [28, 64] years, and 73% male. Fifty pts met criteria for CAT+, 64 pts CAT-, and 370 received no Tx. Risk factors for meeting CAT+: decreased arrival systolic blood pressure (OR 2.82 [2.17, 3.67]), increased INR (OR 2.09, [1.66, 2.62]) and decreased time to peak OR 2.27 [1.74, 2.95]). These variables remained independently associated with increased risk of requiring Tx in a multivariable logistic model, after adjusting for sex and trauma type.

CONCLUSIONS

Pts in hemorrhagic shock, who meet CAT+ criteria, are characterized by accelerated thrombin generation. In our multivariable analysis, both ttPeak and PT/INR have a complementary role in predicting those injured patients who will require a high rate of Tx.

Hypocalcemia in trauma patients: A systematic review

BACKGROUND

During hemorrhagic shock and subsequent resuscitation, pathways reliant upon calcium such as platelet function, intrinsic and extrinsic hemostasis, and cardiac contractility are disrupted. The objective of this systematic review was to examine current literature for associations between pretransfusion, admission ionized hypocalcemia, and composite outcomes including mortality, blood transfusion requirements, and coagulopathy in adult trauma patients.

METHODS

This review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. We searched Ovid MEDLINE and grey literature from database inception till May 3, 2020. Case series and reports were excluded. Reference lists of appraised studies were also screened for articles that the aforementioned databases might not have captured. The Newcastle-Ottawa Scale was used to assess study quality.

RESULTS

A total of 585 abstracts were screened through database searching and alternative sources. Six unique full-text studies were reviewed, of which three were excluded. Admission ionized hypocalcemia was present in up to 56.2% of the population in studies included in this review. Admission ionized hypocalcemia was also associated with increased mortality in all three studies, with increased blood transfusion requirements in two studies, and with coagulopathy in one study.

CONCLUSION

Hypocalcemia is a common finding in shocked trauma patients. While an association between admission ionized hypocalcemia and mortality, blood transfusion requirements, and coagulopathy has been identified, further prospective trials are essential to corroborating this association.

LEVEL OF EVIDENCE

Systematic review, level III.

Freeze-dried platelets promote clot formation, attenuate endothelial cell permeability, and decrease pulmonary vascular leak in a murine model of hemorrhagic shock

BACKGROUND

Hemorrhagic shock (HS) and trauma induce endothelial barrier compromise, inflammation, and aberrant clotting. We have shown that fresh human platelets (Plts) and Plt extracellular vesicles mitigate vascular leak in murine models of injury. Here, we investigate the potential of freeze-dried platelets (FDPlts) to attenuate pulmonary vascular permeability, decrease inflammation, and promote clotting in a murine model of HS.

METHODS

Human FDPlts were characterized using in vitro assays of Plt marker expression, aggregation, coagulation, and endothelial cell permeability. An intravital model of vascular injury in the mouse cremaster muscle was used to assess the ability of FDPlts to incorporate into clots. Mouse groups subjected to controlled hemorrhage for 90 minutes were (1) lactated Ringer solution (LR), (2) FDPlts, (3) fresh human Plts, (4) murine whole blood (WB), and (5) shams (only instrumented). Hemorrhagic shock mouse endpoints included coagulation, pulmonary vascular permeability, and lung injury.

RESULTS

Freeze-dried Plts expressed Plt-specific markers and retained functionality similar to fresh Plts. In in vitro assays of Plt aggregation, differences were noted. In vivo, FDPlts and Plts were found to incorporate into clots in postcapillary venules in the mouse cremaster muscle. Hemorrhagic shock mice resuscitated with LR displayed increased pulmonary vascular permeability compared with sham (sham, 686.6 ± 359.7; shock-LR, 2,637 ± 954.7; p = 0.001), and treatment with FDPlts or WB attenuated permeability compared with shock: shock-FDPlts, 1,328 ± 462.6 (p = 0.05), and shock-WB, 1,024 ± 370.5 (p = 0.0108). However, human Plts (Days 1-3) did not attenuate vascular leak in HS mice compared with shock-LR (shock-Plts, 3,601 ± 1,581; p = 0.33).

CONCLUSION

FDPlts contribute to clot formation similar to fresh human Plts. FDPlts also attenuated vascular permeability in vitro and in vivo. Mouse WB resuscitation but not fresh human Plts attenuated vascular permeability after HS. These data suggest that the effect of FDPlts may be a suitable alternative to fresh Plts in modulating hemostasis and the endotheliopathy associated with injury.

Elevated cytokine, chemokine, and growth and differentiation factor-15 levels in hemorrhagic shock and encephalopathy syndrome: A retrospective observational study

Patients with hemorrhagic shock and encephalopathy syndrome (HSES) have a high early mortality rate, which may be caused by a 'cytokine storm'. However, there is little information on how cytokines and chemokines change over time in these patients. We aimed to describe the characteristics of HSES by examining changes in serum biomarker levels over time. Six patients with HSES were included. We retrospectively evaluated their clinical course and imaging/laboratory data. We measured serum levels of multiple cytokines [interleukin 1β (IL-1β), IL-2, IL-4, IL-6, IL-10, IL-17, interferon-gamma, and tumor necrosis factor alpha], chemokines (IL-8, monocyte chemoattractant protein-1, interferon-inducible protein-10), and growth and differentiation factor (GDF)-15. The highest cytokine and chemokine levels were noted in the first 24 h, and decreased thereafter. The GDF-15 level was markedly high. Cytokine, chemokine, and GDF-15 levels were significantly higher in patients with HSES than in controls in the first 24 h, except for IL-2 and IL-4. Patients with HSES have high inflammatory cytokine and chemokine levels, a high GDF-15 level in the first 24 h, and high lactate levels. Our study provides new insights on the pathophysiology of HSES, a detailed clinical picture of patients with HSES, and potential biomarkers.

Addition of terlipressin to initial volume resuscitation in a pediatric model of hemorrhagic shock improves hemodynamics and cerebral perfusion

Hemorrhagic shock is one of the leading causes of mortality and morbidity in pediatric trauma. Current treatment based on volume resuscitation is associated to adverse effects, and it has been proposed that vasopressors may be used in the pharmacological management of trauma. Terlipressin has demonstrated its usefulness in other pediatric critical care scenarios and its long half-life allows its use as a bolus in an outpatient critical settings. The aim of this study was to analyze whether the addition of a dose of terlipressin to the initial volume expansion produces an improvement in hemodynamic and cerebral perfusion at early stages of hemorrhagic shock in an infant animal model. We conducted an experimental randomized animal study with 1-month old pigs. After 30 minutes of hypotension (mean arterial blood pressure [MAP]<45 mmHg) induced by the withdrawal of blood over 30 min, animals were randomized to receive either normal saline (NS) 30 mL/kg (n = 8) or a bolus of 20 mcg/kg of terlipressin plus 30 mL/kg of normal saline (TP) (n = 8). Global hemodynamic and cerebral monitoring parameters, brain damage markers and histology samples were compared. After controlled bleeding, significant decreases were observed in MAP, cardiac index (CI), central venous pressure, global end-diastolic volume index (GEDI), left cardiac output index, SvO₂, intracranial pressure, carotid blood flow, bispectral index (BIS), cerebral perfusion pressure (CPP) and increases in systemic vascular resistance index, heart rate and lactate. After treatment, MAP, GEDI, CI, CPP and BIS remained significantly higher in the TP group. The addition of a dose of terlipressin to initial fluid resuscitation was associated with hemodynamic improvement, intracranial pressure maintenance and better cerebral perfusion, which would mean protection from ischemic injury. Brain monitoring through BIS was able to detect changes caused by hemorrhagic shock and treatment.

Study on coagulation profiles and platelet function in trauma-induced coagulopathy caused by three types of injury

BACKGROUND

Traumatic coagulopathy is a major public health issue globally with undefined mechanisms. We established rat models of hemorrhagic shock (HS), multiple injury (MI) and traumatic brain injury (TBI) to investigate the diversity of traumatic coagulopathy, especially platelet dysfunction.

METHODS

Seventy male SD rats were divided randomly into seven groups(n = 10): control, HS_30min, HS_3h, MI_30min, MI_3h, TBI_30min and TBI_3h. Plasma or whole blood was collected for conventional coagulation tests, thromboelastography and platelet mapping. X-ray, 7T magnetic resonance imaging and hematoxylin-eosin staining of injured tissues were conducted to confirm the injuries of rats model.

RESULTS

The activated partial thromboplastin time (aPTT) prolonged significantly in HS_30min and MI_3h groups, compared with those in control (P = 0.0403 and P = 0.0076, respectively). R values decreased in HS_30min and HS_3h groups, compared with those in control (P < 0.0001 and P < 0.0001, respectively). The maximum amplitude (MA) were 71.8 ± 0.6 mm, 71.9 ± 0.5 mm, 71.8 ± 0.7 mm, 70.0 ± 0.7 mm, 72.6 ± 0.9 mm, 70.4 ± 0.9 mm in HS_30min, HS_3h, MI_30min, MI_3h, TBI_30min and TBI_3h groups respectively, which were lower than those in control (P = 0.0304, P = 0.0205, P = 0.0431, P = 0.0007 and P = 0.0066, respectively). The platelet counts were 539±46 × 10⁹/L, 523±31 × 10⁹/L, 629 ± 18 × 10⁹/L and 636±20 × 10⁹/L in HS_30min, HS_3h, MI_3h and TBI_3h groups respectively, which were lower than those in control (P = 0.0040, P = 0.0001, P = 0.0127 and P = 0.0232, respectively). The adenosine diphosphate (ADP) inhibition rate decreased in HS_30min group, compared with that in control (P = 0.0355). While, ADP inhibition rate increased in HS_3h and TBI_3h groups (P = 0.0041 and P = 0.0433 vs. control, respectively). The arachidonic acid (AA) inhibition rate increased in MI_30min and MI_3h groups, compared with control (P = 0.0029 and P = 0.0185, respectively).

CONCLUSION

These results demonstrated that it might be the failure of forming a strong clot instead of the prolonged clot time, which contributed to traumatic coagulopathy. The platelet dysfunctions might contribute to trauma-induced coagulopathy in different ways. The loss of platelets might be the main reason for HS-induced coagulopathy. While, AA-dependent pathway inhibition might account for MI-induced coagulopathy. ADP-dependent pathway inhibition might be the major contributor for TBI-induced coagulopathy.

Forgot calcium? Admission ionized-calcium in two civilian randomized controlled trials of prehospital plasma for traumatic hemorrhagic shock

BACKGROUND

Randomized clinical trials (RCTs) support the use of prehospital plasma in traumatic hemorrhagic shock, especially in long transports. The citrate added to plasma binds with calcium, yet most prehospital trauma protocols have no guidelines for calcium replacement. We reviewed the experience of two recent prehospital plasma RCTs regarding admission ionized-calcium (i-Ca) blood levels and its impact on survival. We hypothesized that prehospital plasma is associated with hypocalcemia, which in turn is associated with lower survival.

METHODS

We studied patients enrolled in two institutions participating in prehospital plasma RCTs (control, standard of care; experimental, plasma), with i-Ca collected before calcium supplementation. Adults with traumatic hemorrhagic shock (systolic blood pressure ≤70 mm Hg or 71-90 mm Hg + heart rate ≥108 bpm) were eligible. We use generalized linear mixed models with random intercepts and Cox proportional hazards models with robust standard errors to account for clustered data by institution. Hypocalcemia was defined as i-Ca of 1.0 mmol/L or less.

RESULTS

Of 160 subjects (76% men), 48% received prehospital plasma (median age, 40 years [interquartile range, 28-53 years]) and 71% suffered blunt trauma (median Injury Severity Score [ISS], 22 [interquartile range, 17-34]). Prehospital plasma and control patients were similar regarding age, sex, ISS, blunt mechanism, and brain injury. Prehospital plasma recipients had significantly higher rates of hypocalcemia compared with controls (53% vs. 36%; adjusted relative risk, 1.48; 95% confidence interval [CI], 1.03-2.12; p = 0.03). Severe hypocalcemia was significantly associated with decreased survival (adjusted hazard ratio, 1.07; 95% CI, 1.02-1.13; p = 0.01) and massive transfusion (adjusted relative risk, 2.70; 95% CI, 1.13-6.46; p = 0.03), after adjustment for confounders (randomization group, age, ISS, and shock index).

CONCLUSION

Prehospital plasma in civilian trauma is associated with hypocalcemia, which in turn predicts lower survival and massive transfusion. These data underscore the need for explicit calcium supplementation guidelines in prehospital hemotherapy.

LEVEL OF EVIDENCE

Therapeutic, level II.

RAGE-induced ILC2 expansion in acute lung injury due to haemorrhagic shock

BACKGROUND

Type 2 immune dysfunction contributes to acute lung injury and lethality following haemorrhagic shock (HS) and trauma. Group 2 innate lymphoid cells (ILC2s) play a significant role in the regulation of type 2 immune responses. However, the role of ILC2 in post-HS acute lung injury and the underlying mechanism has not yet been elucidated.

OBJECTIVE

To investigate the regulatory role of ILC2s in HS-induced acute lung injury and the underlying mechanism in patients and animal model.

METHODS

Circulating markers of type 2 immune responses in patients with HS and healthy controls were characterised. Using a murine model of HS, the role of high-mobility group box 1 (HMGB1)-receptor for advanced glycation end products (RAGE) signalling in regulation of ILC2 proliferation, survival and function was determined. And the role of ILC2 in inducing type 2 immune dysfunction was assessed as well.

RESULTS

The number of ILC2s was significantly increased in the circulation of patients with HS that was correlated with the increase in the markers of type 2 immune responses in the patients. Animal studies showed that HMGB1 acted via RAGE to induce ILC2 accumulation in the lungs by promoting ILC2 proliferation and decreasing ILC2 death. The expansion of ILC2s resulted in type 2 cytokines secretion and eosinophil infiltration in the lungs, both of which contributed to lung injury after HS.

CONCLUSIONS

These results indicate that HMGB1-RAGE signalling plays a critical role in regulating ILC2 biological function that aggravates type 2 lung inflammation following HS.

Temporal map of the pig polytrauma plasma proteome with fluid resuscitation and intravenous vitamin C treatment

BACKGROUND

Fluid resuscitation plays a prominent role in stabilizing trauma patients with hemorrhagic shock yet there remains uncertainty with regard to optimal administration time, volume, and fluid composition (e.g., whole blood, component, colloids) leading to complications such as trauma-induced coagulopathies (TIC), acidosis, and poor oxygen transport. Synthetic fluids in combination with antioxidants (e.g., vitamin C) may resolve some of these problems.

OBJECTIVES

We applied quantitative mass spectrometry-based proteomics [liquid chromatography-mass spectrometry (LC-MS/MS)] to map the effects of fluid resuscitation and intravenous vitamin C (VitC) in a pig model of polytrauma (hemorrhagic shock, tissue injury, liver reperfusion, hypothermia, and comminuted bone fracture). The goal was to determine the effects of VitC on plasma protein expression, with respect to changes associated with coagulation and trauma-induced coagulopathy (TIC).

METHODS

Longitudinal blood samples were drawn from nine male Sinclair pigs at baseline, 2 h post trauma, and 0.25, 2, and 4 h post fluid resuscitation with 500 mL hydroxyethyl starch. Pigs were treated intravenously (N = 3/treatment group) with saline, 50 mg VitC/kg (Lo-VitC), or 200 mg VitC/kg (Hi-VitC) during fluid resuscitation.

RESULTS

A total of 436 plasma proteins were quantified of which 136 changed following trauma and resuscitation; 34 were associated with coagulation, complement cascade, and glycolysis. Unexpectedly, Lo-VitC and Hi-VitC treatments stabilized ADAMTS13 levels by ~4-fold (P = .056) relative to saline and enhanced ADAMTS13/von Willebrand factor (VWF) cleavage efficiency based on LC-MS/MS evidence for the semitryptic VWF cleavage product (VWF1275-1286 ).

CONCLUSIONS

This study provides the first comprehensive map of trauma-induced changes to the plasma proteome, especially with respect to proteins driving the development of TIC.

Metal-Organic Framework Encapsulating Hemoglobin as a High-Stable and Long-Circulating Oxygen Carriers to Treat Hemorrhagic Shock

As an oxygen-transporting protein, free hemoglobin (Hb) often suffers from the disadvantage of undesirable stability and short blood circulation, which severely impairs the potential clinical applications as the blood substitute. In this work, Hb was facilely encapsulated into a kind of metal-organic frameworks (MOFs) (ZIF-8) inspired by the natural biomineralization process. The obtained ZIF-8 encapsulating Hb (ZIF-8@Hb) showed the small hydrodynamic size of 180.8 nm and neutral zeta potential of -2.1 mV by adjusting the ratio of Hb in ZIF-8 frameworks. Intriguingly, Hb encapsulated by ZIF-8 exhibited significantly enhanced stability in alkaline, oxidation, high temperature, or enzymatic environment compared with free Hb because of the excellent protective MOF coatings. More importantly, the negative charge of Hb neutralized the original positive charge of ZIF-8, which led to the better biocompatibility, lower protein adsorption, and macrophage uptake of ZIF-8@Hb than bare ZIF-8 nanoparticles. Furthermore, ZIF-8@Hb displayed extended blood circulation with the elimination half-life of 13.9 h as well as reduced nonspecific distribution in normal organs compared with free Hb or ZIF-8 nanoparticles. With the above advantages, ZIF-8@Hb showed significantly extended survival time of mice in a disease model of hemorrhagic shock compared with free Hb or bare ZIF-8 nanoparticles. Overall, this work offers a high-stable and long-circulating oxygen carrier platform, which may find wide applications as a blood substitute to treat various oxygen-relevant diseases.

Comparison of Intraosseous, Arterial, and Venous Blood Sampling for Laboratory Analysis in Hemorrhagic Shock

BACKGROUND

Intraosseous (IO) access is often indicated for administration of drugs and fluids in emergencies when venous access is challenging. There is no consensus regarding whether and which laboratory analyses may be performed on IO aspirates, and research on hemodynamically unstable subjects is limited.

METHODS

Twelve anesthetized pigs were sampled from IO, venous, and arterial accesses during stable circulation and after hemorrhage corresponding to 20% and 40% of the blood volume. Samples were analyzed for blood gases and acid-base status, electrolytes, hematocrit, creatinine, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (γ-GT), alkaline phosphatase (ALP), and creatine kinase (CK).

RESULTS

Average differences of blood gases and acid-base parameters, sodium, creatinine, hematocrit, ALT, and γ-GT and between IO and venous samples were small at baseline and after hemorrhage while differences for lactate and glucose increased with hypovolemia. Both IO-arterial and venoarterial differences in acid-base parameters increased with hypovolemia. Dispersions of differences were often large.

CONCLUSIONS

Average levels of blood gases, acid base parameters, hematocrit, CK, AST, γ-GT, creatinine, and ALT, but not lactate and glucose, were similar in IO and venous samples in hypovolemia. However, precision was limited, indicating that IO test results should be confirmed when other vascular access is established, and that analysis of IO samples should be limited to acute situations and not used for detailed diagnostics in this setting.

Trauma-induced coagulopathy: The past, present, and future

Trauma remains a leading cause of death worldwide, and most early preventable deaths in both the civilian and military settings are due to uncontrolled hemorrhage, despite paradigm advances in modern trauma care. Combined tissue injury and shock result in hemostatic failure, which has been identified as a multidimensional molecular, physiologic and clinical disorder termed trauma-induced coagulopathy (TIC). Understanding the biology of TIC is of utmost importance, as it is often responsible for uncontrolled bleeding, organ failure, thromboembolic complications, and death. Investigations have shown that TIC is characterized by multiple phenotypes of impaired hemostasis due to altered biology in clot formation and breakdown. These coagulopathies are attributable to tissue injury and shock, and encompass underlying endothelial, immune and inflammatory perturbations. Despite the recognition and identification of multiple mechanisms and mediators of TIC, and the development of targeted treatments, the mortality rates and associated morbidities due to hemorrhage after injury remain high. The purpose of this review is to examine the past and present understanding of the multiple distinct but highly integrated pathways implicated in TIC, in order to highlight the current knowledge gaps and future needs in this evolving field, with the aim of reducing morbidity and mortality after injury.

Protective Effects of the Complement Inhibitor Compstatin CP40 in Hemorrhagic Shock

Trauma-induced hemorrhagic shock (HS) plays a decisive role in the development of immune, coagulation, and organ dysfunction often resulting in a poor clinical outcome. Imbalanced complement activation is intricately associated with the molecular danger response and organ damage after HS. Thus, inhibition of the central complement component C3 as turnstile of both inflammation and coagulation is hypothesized as a rational strategy to improve the clinical course after HS.Applying intensive care conditions, anaesthetized, monitored, and protectively ventilated nonhuman primates (NHP; cynomolgus monkeys) received a pressure-controlled severe HS (60 min at mean arterial pressure 30 mmHg) with subsequent volume resuscitation. Thirty minutes after HS, animals were randomly treated with either an analog of the C3 inhibitor compstatin (i.e., Cp40) in saline (n = 4) or with saline alone (n = 4). The observation period lasted 300 min after induction of HS.We observed improved kidney function in compstatin Cp40-treated animals after HS as determined by improved urine output, reduced damage markers and a tendency of less histopathological signs of acute kidney injury. Sham-treated animals revealed classical signs of mucosal edema, especially in the ileum and colon reflected by worsened microscopic intestinal injury scores. In contrast, Cp40-treated HS animals exhibited only minor signs of organ edema and significantly less intestinal damage. Furthermore, early systemic inflammation and coagulation dysfunction were both ameliorated by Cp40.The data suggest that therapeutic inhibition of C3 is capable to significantly improve immune, coagulation, and organ function and to preserve organ-barrier integrity early after traumatic HS. C3-targeted complement inhibition may therefore reflect a promising therapeutic strategy in fighting fatal consequences of HS.

Tranexamic acid decreases rodent hemorrhagic shock-induced inflammation with mixed end-organ effects

Beyond its anti-fibrinolytic mechanism, tranexamic acid has been suggested to have anti-inflammatory properties which may contribute to the survival benefit it provides to trauma patients. The objective of this study was to assess possible immunomodulatory effects of tranexamic acid as well as potential amelioration of end-organ injury in a rodent hemorrhagic shock model. Controlled hemorrhagic shock was induced in adult Sprague Dawley rats to a mean arterial pressure of 30 mmHg. Groups of 10 rats were administered intravenous tranexamic acid (300mg/kg) or vehicle control (normal saline) intravenously 15 minutes after the induction of shock. After 60 minutes of hemorrhagic shock, resuscitation was started. Animals were euthanized at six, 24, or 72 hours from the start of shock. Serum laboratory values to include inflammatory biomarkers were measured, and end organ histology was evaluated. Tranexamic acid treatment was associated with a significant decrease in serum IL-1β at six and 24 hours and IL-10 at 24 hours from start of shock compared to vehicle control. Histologic analysis demonstrated mild decreases in both perivascular pulmonary edema and follicular mesenteric lymph node hyperplasia in the tranexamic acid treatment group but also increased myocardial lymphocytic infiltration with necrosis and degeneration. Tranexamic acid was also associated with a small but significant increase in peripheral neutrophil count as well as a significant decrease in neutrophil aggregation in pulmonary tissue at six hours post-injury. These data thus demonstrate a mixed effect of tranexamic acid. While there was an improvement in pulmonary edema and a suppressive effect on several key inflammatory mediators, there was also increased myocardial degeneration and necrosis, which is possibly related to the pro-thrombotic effect of tranexamic acid.

Recommendations on RBC Transfusion in Critically Ill Children With Nonlife-Threatening Bleeding or Hemorrhagic Shock From the Pediatric Critical Care Transfusion and Anemia Expertise Initiative

OBJECTIVES

To present the recommendations and supporting literature for RBC transfusions in critically ill children with bleeding developed by the Pediatric Critical Care Transfusion and Anemia Expertise Initiative.

DESIGN

Consensus conference series of international, multidisciplinary experts in RBC transfusion management of critically ill children.

METHODS

The panel of 38 experts developed evidence-based and, when evidence was lacking, expert-based clinical recommendations as well as research priorities for RBC transfusions in critically ill children. The bleeding subgroup included five experts. Electronic searches were conducted using PubMed, EMBASE, and Cochrane Library databases from 1980 to May 2017. Agreement was obtained using the Research and Development/UCLA Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method.

RESULTS

Transfusion and Anemia Expertise Initiative Consensus Conference experts developed a total of six recommendations focused on transfusion in the critically ill child with acute bleeding. In critically ill children with nonlife-threatening bleeding, we recommend giving a RBC transfusion for a hemoglobin concentration less than 5 g/dL, and be considered for a hemoglobin concentration between 5 and 7 g/dL. In critically ill children with hemorrhagic shock, we suggest that RBCs, plasma and platelets transfusion ratio between 2:1:1 to 1:1:1 until the bleeding is no longer life-threatening. We recommend future studies to develop physiologic and laboratory measures to indicate the need for RBC transfusions, and to determine if goal directed hemostatic resuscitation improves survival. Finally, we recommend future studies to determine if low titer group O whole blood is more efficacious and safe compared with reconstituted whole blood in children with hemorrhagic shock.

CONCLUSIONS

The Transfusion and Anemia Expertise Initiative Consensus Conference developed pediatric specific recommendations regarding RBC transfusion management in the critically ill child with acute bleeding, as well as recommendations to help guide future research priorities.

Organ-Specific Oxidative Events under Restrictive Versus Full Reperfusion Following Hemorrhagic Traumatic Shock in Rats

Background aim: Reperfusion after hemorrhagic traumatic shock (HTS) is often associated with complications that are partly ascribed to the formation of reactive oxygen species (ROS). The aim of our study was to compare the effects of restrictive reperfusion (RR) to rapid full reperfusion (FR) on ROS formation and/or oxidative events.

MATERIALS AND METHODS

Anesthetized male rats were randomly subjected to HTS followed by FR (75 mL/kg/h) or RR (30 mL/kg/h for 40 min, followed by 75 mL/kg/h) with Ringer's solution (n = 8/group). Compartment-specific ROS formation was determined by infusion of ROS scavenger 1-hydroxy-3-carboxy-2,2,5,5-tetramethyl-pyrrolidine hydrochloride (CP-H) during resuscitation, followed by electron paramagnetic resonance spectroscopy. Sham-operated animals (n = 8) served as controls. The experiment was terminated 100 min post-shock.

RESULTS

Mean arterial pressure was significantly higher in the FR compared to the RR group during early reperfusion. Only RR animals, not FR animals, showed significantly higher ROS concentrations in erythrocytes (1951 ± 420 vs. 724 ± 75 AU) and in liver (474 ± 57 vs. 261 ± 21 AU) compared to sham controls. This was accompanied by elevated alanine aminotransferase and creatinine levels in RR animals compared to both shams and FR animals, while lipid peroxidation products (thiobarbituric acid reactive substances) were significantly increased only in the kidney in the FR group (p < 0.05). RR animals showed significantly higher plasma peroxiredoxin-4 values when compared to the FR group (20 ± 2 vs. 14 ± 0.5 RLU).

CONCLUSION

Restrictive reperfusion after HTS is associated with increased ROS formation in erythrocytes and liver compared to sham controls. Moreover, the restrictive reperfusion is associated with a more pronounced injury to the liver and kidney, which is likely mediated by other than lipid peroxidation process and/or oxidative stress reactions.

In vivo performance of a visible wavelength optical sensor for monitoring intestinal perfusion and oxygenation

Traumatic injury resulting in hemorrhage is a prevalent cause of death worldwide. The current standard of care for trauma patients is to restore hemostasis by controlling bleeding and administering intravenous volume resuscitation. Adequate resuscitation to restore tissue blood flow and oxygenation is critical within the first hours following admission to assess severity and avoid complications. However, current clinical methods for guiding resuscitation are not sensitive or specific enough to adequately understand the patient condition. To better address the shortcomings of the current methods, an approach to monitor intestinal perfusion and oxygenation using a multiwavelength (470, 560, and 630 nm) optical sensor has been developed based on photoplethysmography and reflectance spectroscopy. Specifically, two sensors were developed using three wavelengths to measure relative changes in the small intestine. Using vessel occlusion, systemic changes in oxygenation input, and induction of hemorrhagic shock, the capabilities and sensitivity of the sensor were explored in vivo. Pulsatile and nonpulsatile components of the red, blue, and green wavelength signals were analyzed for all three protocols (occlusion, systemic oxygenation changes, and shock) and were shown to differentiate perfusion and oxygenation changes in the jejunum. The blue and green signals produced better correlation to perfusion changes during occlusion and shock, while the red and blue signals, using a new correlation algorithm, produced better data for assessing changes in oxygenation induced both systemically and locally during shock. The conventional modulation ratio method was found to be an ineffective measure of oxygenation in the intestine due to noise and an algorithm was developed based on the Pearson correlation coefficient. The method utilized the difference in phase between two different wavelength signals to assess oxygen content. A combination of measures from the three wavelengths provided verification of oxygenation and perfusion states, and showed promise for the development of a clinical monitor.

The Metabolopathy of Tissue Injury, Hemorrhagic Shock, and Resuscitation in a Rat Model

INTRODUCTION

The metabolic consequences of trauma induce significant clinical pathology. In this study, we evaluate the independent, metabolic contributions of tissue injury (TI) and combined tissue injury and hemorrhagic shock (TI/HS) using mass spectrometry (MS) metabolomics in a controlled animal model of critical injury.

METHODS

Sprague-Dawley rats (n = 14) underwent TI alone or TI/HS, followed by resuscitation with normal saline and shed blood. Plasma was collected (baseline, post-laparotomy, post-HS, post-resuscitation) for ultra-high pressure liquid chromatography MS-metabolomics. Repeated-measures ANOVA with Tukey multiple column comparison test compared the fold change of metabolite concentration among the animal groups at corresponding time points.

RESULTS

Four hundred forty metabolites were identified. TI alone did not change the metabolite levels versus baseline. TI/HS induced changes in metabolites from glycolysis, the tricarboxylic acid cycle, the pentose phosphate, fatty acid and glutathione homeostasis pathways, sulfur metabolism, and urea cycle versus TI alone. Following resuscitation many metabolites normalized to TI alone levels, including lactate, most tri-carboxylic acid metabolites, most urea cycle metabolites, glutathione disulfide, and some metabolites from both the pentose phosphate pathway and sulfur metabolism.

CONCLUSIONS

Significant changes occur immediately following TI/HS versus TI alone. These metabolic changes are not explained by dilution as a number of metabolites remained unchanged or even increased following resuscitation. The differential metabolic changes resulting from TI alone and TI/HS provide foundation for future investigations severe injury in humans, where TI and HS are often concurrent. This investigation provides a foundation to evaluate metabolic-related outcomes and design-targeted resuscitation strategies.

Alterations of Mg2+ After Hemorrhagic Shock

Hemorrhagic shock is generally characterized by hemodynamic instability with cellular hypoxia and diminishing cellular function, resulting from an imbalance between systemic oxygen delivery and consumption and redistribution of fluid and electrolytes. Magnesium (Mg) is the fourth most abundant cation overall and second most abundant intracellular cation in the body and an essential cofactor for the energy production and cellular metabolism. Data for blood total Mg (tMg; free-ionized, protein-bound, and anion-bound forms) and free Mg²⁺ levels after a traumatic injury are inconsistent and only limited information is available on hemorrhagic effects on free Mg²⁺ as the physiologically active form. The aim of this study was to determine changes in blood Mg²⁺ and tMg after hemorrhage in rats identifying mechanism and origin of the changes in blood Mg²⁺. Hemorrhagic shock produced significant increases in blood Mg²⁺, plasma tMg, Na⁺, K⁺, Cl^-, anion gap, partial pressures of oxygen, glucose, and blood urea nitrogen but significant decreases in RBC tMg, blood Ca²⁺, HCO₃^-, pH, partial pressures of carbon dioxide, hematocrit, hemoglobin, total cholesterol, and plasma/RBC ATP. During hemorrhagic shock, K⁺, anion gap, and BUN showed significant positive correlations with changes in blood Mg²⁺ level, while Ca²⁺, pH, and T-CHO correlated to Mg²⁺ in a negative manner. In conclusion, hemorrhagic shock induced an increase in both blood-free Mg²⁺ and tMg, resulted from Mg²⁺ efflux from metabolic damaged cell with acidosis and ATP depletion.

Hemorrhagic shock and tissue injury drive distinct plasma metabolome derangements in swine

BACKGROUND

Tissue injury and hemorrhagic shock induce significant systemic metabolic reprogramming in animal models and critically injured patients. Recent expansions of the classic concepts of metabolomic aberrations in tissue injury and hemorrhage opened the way for novel resuscitative interventions based on the observed abnormal metabolic demands. We hypothesize that metabolic demands and resulting metabolic signatures in pig plasma will vary in response to isolated or combined tissue injury and hemorrhagic shock.

METHODS

A total of 20 pigs underwent either isolated tissue injury, hemorrhagic shock, or combined tissue injury and hemorrhagic shock referenced to a sham protocol (n = 5/group). Plasma samples were analyzed by UHPLC-MS.

RESULTS

Hemorrhagic shock promoted a hypermetabolic state. Tissue injury alone dampened metabolic responses in comparison to sham and hemorrhagic shock, and attenuated the hypermetabolic state triggered by shock with respect to energy metabolism (glycolysis, glutaminolysis, and Krebs cycle). Tissue injury and hemorrhagic shock had a more pronounced effect on nitrogen metabolism (arginine, polyamines, and purine metabolism) than hemorrhagic shock alone.

CONCLUSION

Isolated or combined tissue injury and hemorrhagic shock result in distinct plasma metabolic signatures. These findings indicate that optimized resuscitative interventions in critically ill patients are possible based on identifying the severity of tissue injury and hemorrhage.

Crocin attenuates hemorrhagic shock-induced oxidative stress and organ injuries in rats

We aimed to evaluate the effect of natural antioxidant crocin in alleviating hemorrhagic shock (HS)-induced organ damages. HS rats were treated with crocin during resuscitation. Mortality at 12h and 24h post resuscitation was documented. HS and resuscitation induced organ injuries, as characterized by elevated wet/dry ratio, quantitative assessment ratio, blood urea nitrogen, creatinine, aspartate aminotransferase and alanine aminotransferase, whereas rats received crocin treatment demonstrated improvements in all the above characteristics. This protective effect coincided with reduced malondialdehyde and increased glutathione in both serum and lung tissues, indicating attenuated oxidative stress in crocin-treated rats. Myeloperoxide levels in lung, kidney and liver were also reduced. Crocin can potentially be used to protect organs from HS-induced damages during resuscitation due to its anti-oxidative role.

Resuscitation Affects Microcirculatory Polymorphonuclear Leukocyte Behavior After Hemorrhagic Shock: Role of Hypertonic Saline and Pentoxifylline

We have previously shown that lung injury following fluid resuscitation either with hypertonic saline (HS) or lactated Ringer's (LR) plus pentoxifylline (PTX) attenuated acute lung injury when compared with LR resuscitation. The objective of the present study is to determine whether our previous observations are accompanied by changes in polymorphonuclear leukocyte (PMN) behavior. To study this, PMN-endothelial cell interactions, microcirculatory blood flow, lung histology, lung PMN infiltration (WIPO, Myeloperoxidase), and lung intracellular adhesion molecule-1 (ICAM-1) expression were assessed in a controlled hemorrhagic shock model followed by LR, HS, and LR+PTX resuscitation in rodents. Rats (240-300 g) were bled to a mean arterial pressure (MAP) of 35 mm Hg for 1 hr and then randomized into three groups: HS (7.5% NaCl, 4 ml/kg); LR (3× shed blood); and LR+PTX (25 mg/kg). Additionally, total shed blood was reinfused. A sham group underwent no shock and no treatment. The internal spermatic fascia was exteriorized and the microcirculation was observed by closed-circuit TV coupled to a microscope, 2 and 6 hrs after treatment. The number of leukocytes sticking to the venular endothelium was determined 2 hrs after fluid resuscitation. Microcirculatory blood flow was measured by an optical Doppler velocimeter. Lung histology and lung MPO immunostaining were assessed at 6 hrs, and lung ICAM-1 expression was determined by immunostaining at 2 hrs following fluid resuscitation. Two hours after treatment, HS (1.4 ± 0.4), LR+PTX (1.7 ± 0.3), and sham (0.4 ± 0.2) groups presented significant reductions in leukocyte adherence (cells/100 urn venule length), compared with the LR group (4.0 ± 0.9, P < 0.05). No differences were observed 6 hrs after treatment on leukocyte adherence and microcirculatory blood flow. ICAM-1 expression was significantly higher in LR- treated animals compared with the HS, LR+PTX, and sham groups (P < 0.01). PMN infiltration and overall lung injury were significantly attenuated by HS and LR+PTX. These results support earlier studies that indicated the potential application of HS and PTX in shock therapy and the increase in PMN- endothelial cell interaction and lung injury after LR resuscitation.

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A short overview of hemorrhagic shock in pregnancy, childbirth and postpartum period are presented data from major and recent developments on the subject. Presented a clinical case - pregnant with complications and hemorrhagic shock.

Biliary tract external drainage protects against intestinal barrier injury in hemorrhagic shock rats

AIM: To investigate the effects of biliary tract external drainage (BTED) on intestinal barrier injury in rats with hemorrhagic shock (HS).

METHODS: BTED was performed via cannula insertion into the bile duct of rats. HS was induced by drawing blood from the femoral artery at a rate of 1 mL/min until a mean arterial pressure (MAP) of 40 ± 5 mmHg was achieved. That MAP was maintained for 60 min. A total of 99 Sprague-Dawley rats were randomized into a sham group, an HS group and an HS + BTED group. Nine rats in the sham group were sacrificed 0.5 h after surgery. Nine rats in each of the HS and HS + BTED groups were sacrificed 0.5 h, 1 h, 2 h, 4 h and 6 h after resuscitation. Plasma tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and lipopolysaccharide (LPS) levels were analyzed using enzyme-linked immunosorbent assay. Plasma D-lactate levels were analyzed using colorimetry. The expression levels of occludin and claudin-1 in the ileum were analyzed using Western blot and immunohistochemistry. Histology of the ileum was evaluated by hematoxylin and eosin staining.

RESULTS: Plasma TNF-α levels in the HS + BTED group decreased significantly compared with the HS group at 1 h and 6 h after resuscitation (P < 0.05). Plasma IL-6 levels in the HS + BTED group decreased significantly compared with the HS group at 0.5 h, 1 h and 2 h after resuscitation (P < 0.05). Plasma D-lactate and LPS levels in the HS + BTED group decreased significantly compared with the HS group at 6 h after resuscitation (P < 0.05). The expression levels of occludin in the HS + BTED group increased significantly compared with the HS group at 4 h and 6 h after resuscitation (P < 0.05). The expression levels of claudin-1 in the HS + BTED group increased significantly compared with the HS group at 6 h after resuscitation (P < 0.05). Phenomena of putrescence and desquamation of epithelial cells in the ileal mucosa were attenuated in the HS + BTED group. Ileal histopathologic scores in the HS + BTED group decreased significantly compared with the HS group at 2 h, 4 h and 6 h after resuscitation (P < 0.05).

CONCLUSION: BTED protects against intestinal barrier injury in HS rats.

Trauma/hemorrhagic shock instigates aberrant metabolic flux through glycolytic pathways, as revealed by preliminary (13)C-glucose labeling metabolomics

BACKGROUND

Metabolic derangement is a key hallmark of major traumatic injury. The recent introduction of mass spectrometry-based metabolomics technologies in the field of trauma shed new light on metabolic aberrations in plasma that are triggered by trauma and hemorrhagic shock. Alteration in metabolites associated with catabolism, acidosis and hyperglycemia have been identified. However, the mechanisms underlying fluxes driving such metabolic adaptations remain elusive.

METHODS

A bolus of U-(13)C-glucose was injected in Sprague-Dawley rats at different time points. Plasma extracts were analyzed via ultra-high performance liquid chromatography-mass spectrometry to detect quantitative fluctuations in metabolite levels as well as to trace the distribution of heavy labeled carbon isotopologues.

RESULTS

Rats experiencing trauma did not show major plasma metabolic aberrations. However, trauma/hemorrhagic shock triggered severe metabolic derangement, resulting in increased glucose levels, lactate and carboxylic acid accumulation. Isotopologue distributions in late Krebs cycle metabolites (especially succinate) suggested a blockade at complex I and II of the electron transport chain, likely due to mitochondrial uncoupling. Urate increased after trauma and hemorrhage. Increased levels of unlabeled mannitol and citramalate, metabolites of potential bacterial origin, were also observed in trauma/hemorrhagic shock rats, but not trauma alone or controls.

CONCLUSIONS

These preliminary results are consistent with observations we have recently obtained in humans, and expand upon our early results on rodent models of trauma and hemorrhagic shock by providing the kinetics of glucose fluxes after trauma and hemorrhage. Despite the preliminary nature of this study, owing to the limited number of biological replicates, results highlight a role for shock, rather than trauma alone, in eliciting systemic metabolic aberrations. This study provides the foundation for tracing experiments in rat models of trauma. The goal is to improve our understanding of substrate specific metabolic derangements in trauma/hemorrhagic shock, so as to design resuscitative strategies tailored toward metabolic alterations and the severity of trauma.

Pre-Hospital Induced Hypothermia Improves Outcomes in a Pig Model of Traumatic Hemorrhagic Shock

BACKGROUND

Extensive preclinical evidence suggests that induced hypothermia can protect tissues from ischemia-reperfusion injury, reduce organ damage, and improve survival in the advanced stages of shock.

OBJECTIVES

We assessed the effects of induced hypothermia on the hemodynamic parameters and coagulation capacity during hemorrhagic shock (HS) and fluid resuscitation, in a pig model of HS with multiple intestinal perforations.

MATERIAL AND METHODS

Pigs (n=16) were randomized into 2 groups: a hypothermia (HT) group (n=8, 34°C) and a normothermia (NT) group (n=8, 38°C). Hypothermia to 34°C was induced with a cold blanket at the pre-hospital stage. Traumatic HS shock was induced using multiple intestinal perforations. Pulse indicator continuous cardiac output (PiCCO) was used to monitor hemodynamic changes. Coagulation capacity was measured using thromboelastography (TEG) at baseline as well as during resuscitation periods. Survival was documented for 72 h post-trauma.

RESULTS

Mortality in the hypothermic HS group was low, but there were no significant differences in mortality between the groups (mortality=2/8 HT vs. 5/8 NT, p=0.137). During hypothermia, the heart rate, extravascular lung water index (EVLWI), oxygen uptake index (VO2), and oxygen delivery index (DO2) in the HT group were significantly lower than those in the NT group. There were no significant differences between the 2 groups in the other hemodynamic indices or prothrombin time. Analyses of thromboelastometry at 34°C during hypothermia showed significant differences for reaction time (R) and alpha angle, but not for maximal amplitude (MA).

CONCLUSIONS

Rewarming reversed the coagulation changes induced by hypothermia. Induced mild hypothermia (34°C) in the pre-hospital stage affects hemodynamic parameters and the coagulation system but does not worsen outcomes in a pig HS model. The hypothermia-induced coagulation changes were reversed during rewarming without evidence of harmful effects. Our results suggest that pre-hospital induced hypothermia can be performed carefully following major trauma.

[CORRECTION OF HEMOSTASIS DISORDER IN HEMORRHAGIC SHOCK]

It is a clinical case of successful correction of hemostasis disorder in hemorrhagic shock. This case demonstrates the need to perform advanced tests that assess hemostatic system in patients with ongoing bleeding. Using of thromboelastography helped us to make a comprehensive assessment of hemostatic system that allowed to detect the point of application of drugs and substitution therapy. Coagulation disorder was treated by intravenous injection of Ca2+. In this case the cause of hypocalcemia was combination offactors such as electrolytes losing during massive bleeding and progressing metabolic acidosis. Therefore, monitoring the level of ionized calcium is especially important in patients undergoing massive blood loss and receiving large doses of donor blood components.

'Preconditioning' with low dose lipopolysaccharide aggravates the organ injury / dysfunction caused by hemorrhagic shock in rats

Methods

Male rats were ‘pretreated’ with phosphate-buffered saline (PBS; i.p.) or LPS (1 mg/kg; i.p.) 24 h prior to HS. Mean arterial pressure (MAP) was maintained at 30 ± 2 mmHg for 90 min or until 25% of the shed blood had to be re-injected to sustain MAP. This was followed by resuscitation with the remaining shed blood. Four hours after resuscitation, parameters of organ dysfunction and systemic inflammation were assessed.

Results

HS resulted in renal dysfunction, and liver and muscular injury. At a first glance, LPS preconditioning attenuated organ dysfunction. However, we discovered that HS-rats that had been preconditioned with LPS (a) were not able to sustain a MAP at 30 mmHg for more than 50 min and (b) the volume of blood withdrawn in these animals was significantly less than in the PBS-control group. This effect was associated with an enhanced formation of the nitric oxide (NO) derived from inducible NO synthase (iNOS). Thus, a further control group in which all animals were resuscitated after 50 min of hemorrhage was performed. Then, LPS preconditioning aggravated both circulatory failure and organ dysfunction. Most notably, HS-rats pretreated with LPS exhibited a dramatic increase in NF-κB activation and pro-inflammatory cytokines.

Conclusion

In conclusion, LPS preconditioning predisposed animals to an earlier vascular decompensation, which may be mediated by an excess of NO production secondary to induction of iNOS and activation of NF-κB. Moreover, LPS preconditioning increased the formation of pro-inflammatory cytokines, which is likely to have contributed to the observed aggravation of organ injury/dysfunction caused by HS.

Development of a standardized trauma-related lung injury model

BACKGROUND

The pathophysiology of acute lung injury is multifactorial, and the mechanisms are difficult to prove. We have devised a study of two known and standardized animal models (hemorrhagic shock [HS] and oleic acid [OA]) to more closely reproduce the pathophysiology of posttraumatic acute lung injury.

MATERIAL AND METHODS

Pressure-controlled HS (group HS) was performed by withdrawing blood over 15-min until mean arterial pressure reached 35 mm Hg for 90 min. In an additional group, HS and standardized lung injury induced by OA were combined (group lung injury [HS + OA]). After the shock period, both groups were resuscitated over 15 min by transfusion of the removed blood and an equal volume of lactate Ringer solution. The end point was 6 h. Plasma interleukin (IL)-6, keratinocyte chemoattractant (KC), IL-10, monocyte chemoattractant protein-1 (MCP-1), and lung histology were carried out.

RESULTS

The posttraumatic lung injury group demonstrated significantly higher IL-6 levels when compared with HS group (744.8 ± 104 versus 297.7 ± 134 pg/mL; P = 0.004). Histologic analysis confirmed diffuse alveolar congestion and moderate-to-severe lung edema in animals with HS + OA. Lung injury was mild in mice with isolated HS or OA injection.

CONCLUSIONS

We established a posttraumatic lung injury model combining two different standardized protocols (HS and OA). This model leads to pronounced inflammation and lung injury. This model allows the analysis of the dynamics of sterile lung injury and associated organ dysfunction.

Accuracy of continuous noninvasive hemoglobin monitoring for the prediction of blood transfusions in trauma patients

Early detection of hemorrhagic shock is required to facilitate prompt coordination of blood component therapy delivery to the bedside and to expedite performance of lifesaving interventions. Standard physical findings and vital signs are difficult to measure during the acute resuscitation stage, and these measures are often inaccurate until patients deteriorate to a state of decompensated shock. The aim of this study is to examine a severely injured trauma patient population to determine whether a noninvasive SpHb monitor can predict the need for urgent blood transfusion (universal donor or additional urgent blood transfusion) during the first 12 h of trauma patient resuscitation. We hypothesize that trends in continuous SpHb, combined with easily derived patient-specific factors, can identify the immediate need for transfusion in trauma patients. Subjects were enrolled if directly admitted to the trauma center, >17 years of age, and with a shock index (heart rate/systolic blood pressure) >0.62. Upon admission, a Masimo Radical-7 co-oximeter sensor (Masimo Corporation, Irvine, CA) was applied, providing measurement of continuous non-invasive hemoglobin (SpHb) levels. Blood was drawn and hemoglobin concentration analyzed and conventional pulse oximetry photopletysmograph signals were continuously recorded. Demographic information and both prehospital and admission vital signs were collected. The primary outcome was transfusion of at least one unit of packed red blood cells within 24 h of admission. Eight regression models (C1-C8) were evaluated for the prediction of blood use by comparing area under receiver operating curve (AUROC) at different time intervals after admission. 711 subjects had continuous vital signs waveforms available, to include heart rate (HR), SpHb and SpO2 trends. When SpHb was monitored for 15 min, SpHb did not increase AUROC for prediction of transfusion. The highest ROC was recorded for model C8 (age, sex, prehospital shock index, admission HR, SpHb and SpO2) for the prediction of blood products within the first 3 h of admission. When data from 15 min of continuous monitoring were analyzed, significant improvement in AUROC occurred as more variables were added to the model; however, the addition of SpHb to any of the models did not improve AUROC significantly for prediction of blood use within the first 3 h of admission in comparison to analysis of conventional oximetry features. The results demonstrate that SpHb monitoring, accompanied by continuous vital signs data and adjusted for age and sex, has good accuracy for the prediction of need for transfusion; however, as an independent variable, SpHb did not enhance predictive models in comparison to use of features extracted from conventional pulse oximetry. Nor was shock index better than conventional oximetry at discriminating hemorrhaging and prediction of casualties receiving blood. In this population of trauma patients, noninvasive SpHb monitoring, including both trends and absolute values, did not enhance the ability to predict the need for blood transfusion.

A novel nanobiotherapeutic poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] with no cardiac toxicity for the resuscitation of a rat model with 90 minutes of sustained severe hemorrhagic shock with loss of 2/3 blood volume

We crosslink hemoglobin (Hb), superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) to form a soluble polyHb-SOD-CAT-CA nanobiotechnological complex. The obtained product is a soluble complex with three enhanced red blood cell (RBC) functions and without blood group antigens. In the present study, 2/3 of blood volume was removed to result in 90-min hemorrhagic shock at mean arterial blood pressure (MAP) of 30 mmHg. This was followed by the reinfusion of different resuscitation fluids, then followed for another 60 min. PolyHb-SOD-CAT-CA maintained the MAP at 87.5 ± 5 mmHg as compared with 3 volumes of lactated Ringer's solution, 43.3 ± 2.8 mmHg; blood, 91.3 ± 3.6 mmHg; polyHb-SOD-CAT, 86.0 ± 4.6 mmHg; poly stroma-free hemolysate (polySFHb), 85.0 ± 2.5 mmHg; and polyHb, 82.6 ± 3.5 mmHg. PolyHb-SOD-CAT-CA was superior to the blood and other fluids based on the following criteria. PolyHb-SOD-CAT-CA reduced tissue pCO2 from 98 ± 4.5 mmHg to 68.6 ± 3 mmHg. This was significantly (p < 0.05) more effective than lactated Ringer's solution (98 ± 4.5 mmHg), polyHb (90.1 ± 4.0 mmHg), polyHb-SOD-CAT (90.9 ± 1.4 mmHg), blood (79.1 ± 4.7 mmHg), and polySFHb (77 ± 5 mmHg). PolyHb-SOD-CAT-CA reduced the elevated ST level to 21.7 ± 6.7% and is significantly (< 0.05) better than polyHb (57.7 ± 8.7%), blood (39.1 ± 1.5%), polySFHb (38.3% ± 2.1%), polyHb-SOD-CAT (27.8 ± 5.6%), and lactated Ringer's solution (106 ± 3.1%). The plasma cardiac troponin T (cTnT) level of polyHb-SOD-CAT-CA group was significantly (P < 0.05) lower than that of all the other groups. PolyHb-SOD-CAT-CA reduced plasma lactate level from 18 ± 2.3 mM/L to 6.9 ± 0.3 mM/L. It was significantly more effective (P < 0.05) than lactated Ringer's solution (12.4 ± 0.6 mM/L), polyHb (9.6 ± 0.7 mM/L), blood (8.1 ± 0.2 mM/L), polySFHb (8.4 ± 0.1 mM/L), and polyHb-SOD-CAT (7.6 ± 0.3 mM/L). PolyHb-SOD-CAT-CA can be stored for 320 days at room temperature. Lyophilized poly-Hb-SOD-CAT-CA can be heat pasteurized at 68F for 2 h. This can be important if there is a need to inactivate human immunodeficiency virus, Ebola virus, and other infectious organisms.

Coagulation changes following traumatic brain injury and shock

In these studies, we have shown that coagulation and innate immunity pathways respond to trauma within minutes. Furthermore, the appearance of dysfunction of platelets as well as activation of the endothelium is rapidly manifested. Interestingly, many of these changes were attenuated by treatment with valproic acid (VPA). These most notably included coagulation and endothelial activation as well as platelet dysfunction. These results add to the growing body of evidence indicating a protective effect of VPA following trauma, and suggests that this may in part be mediated through an attenuation of the above-mentioned pathways. Furthermore, these results indicate that VPA treatment may be effective in other pathological settings such as coagulopathy following trauma or sepsis.

[Influence of the nitric oxide donors on the microcirculation in infusion therapy of the experimental hemorrhagic shock]

Infusion of the nitric oxide donors L-Arginine (150 mg/kg bolus) and Oxacom (3,2 µM/ kg bolus) with saline solution has been shown improves cardiovascular and metabolic changes in animal model of hemorrhagic shock. As a result improves survival rats. These data made this effect clinically attractive.

1H-NMR metabolomic biomarkers of poor outcome after hemorrhagic shock are absent in hibernators

Background

Hemorrhagic shock (HS) following trauma is a leading cause of death among persons under the age of 40. During HS the body undergoes systemic warm ischemia followed by reperfusion during medical intervention. Ischemia/reperfusion (I/R) results in a disruption of cellular metabolic processes that ultimately lead to tissue and organ dysfunction or failure. Resistance to I/R injury is a characteristic of hibernating mammals. The present study sought to identify circulating metabolites in the rat as biomarkers for metabolic alterations associated with poor outcome after HS. Arctic ground squirrels (AGS), a hibernating species that resists I/R injury independent of decreased body temperature (warm I/R), was used as a negative control.

Methodology/principal findings

Male Sprague-Dawley rats and AGS were subject to HS by withdrawing blood to a mean arterial pressure (MAP) of 35 mmHg and maintaining the low MAP for 20 min before reperfusing with Ringers. The animals’ temperature was maintained at 37±0.5°C for the duration of the experiment. Plasma samples were taken immediately before hemorrhage and three hours after reperfusion. Hydrophilic and lipid metabolites from plasma were then analyzed via ¹H–NMR from unprocessed plasma and lipid extracts, respectively. Rats, susceptible to I/R injury, had a qualitative shift in their hydrophilic metabolic fingerprint including differential activation of glucose and anaerobic metabolism and had alterations in several metabolites during I/R indicative of metabolic adjustments and organ damage. In contrast, I/R injury resistant AGS, regardless of season or body temperature, maintained a stable metabolic homeostasis revealed by a qualitative ¹H–NMR metabolic profile with few changes in quantified metabolites during HS-induced global I/R.

Conclusions/significance

An increase in circulating metabolites indicative of anaerobic metabolism and activation of glycolytic pathways is associated with poor prognosis after HS in rats. These same biomarkers are absent in AGS after HS with warm I/R.

Serum diamine oxidase as a hemorrhagic shock biomarker in a rabbit model

Background

In prolonged hemorrhagic shock, reductions in intestinal mucosal blood perfusion lead to mucosal barrier damage and systemic inflammation. Gastrointestinal failure in critically ill patients has a poor prognosis, so early assessment of mucosal barrier injury in shock patients is clinically relevant. Unfortunately, there is no serum marker that can accurately assess intestinal ischemia-reperfusion injury.

Objective

The aim of this study was to assess if serum diamine oxidase levels can reflect intestinal mucosal injury subsequent to prolonged hemorrhagic shock.

Methods

Thirty New Zealand white rabbits were divided into three groups: a control group, a medium blood pressure (BP) group (exsanguinated to a shock BP of 50 to 41 mm Hg), and a low BP group (exsanguinated to a shock blood pressure of 40 to 31 mm Hg), in which the shock BP was sustained for 180 min prior to fluid resuscitation.

Results

The severity of hemorrhagic shock in the low BP group was significantly greater than that of the medium BP group according to the post-resuscitation BP, serum tumor necrosis factor (TNF)-α, and arterial lactate. Intestinal damage was significantly more severe in the low BP group according to Chiu’s scoring, claudin-1, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase expression. Serum diamine oxidase was significantly increased in the low BP group compared to the medium BP and control groups and was negatively correlated with shock BP.

Conclusion

Serum diamine oxidase can be used as a serological marker in evaluating intestinal injury and shows promise as an indicator of hemorrhagic shock severity.

Admission red cell distribution width: a novel predictor of massive transfusion after injury

Admission red cell distribution width (aRDW) has been shown to predict mortality in trauma patients by an unclear mechanism. It has been speculated that aRDW is a marker of chronic health status, but elevated RDW may also reflect recent hemorrhage. We hypothesized that aRDW is a predictor of major hemorrhage in trauma patients. Shock trauma patients at a Level I trauma center over 6.5 years were evaluated. Patients were stratified by aRDW quintile (Q1: less than 13%, Q2: 13.1 to 13.5%, Q3: 13.6 to 14.0%, Q4: 14.1 to 14.9%, Q5: 15.0% or greater). Massive transfusion (MT) was defined as 10 or more packed red blood cells in the first 24 hours. From multiple logistic regression, odds ratios with 95 per cent confidence intervals (CIs) were determined to evaluate the association between aRDW quintile and MT. Three thousand nine hundred ninety-four met study criteria. Overall MT incidence was 10 per cent and in-hospital mortality was 17 per cent. MT and mortality increased in a stepwise fashion by aRDW quintile (P < 0.0001). From logistic regression, a threefold increased odds of MT was associated with aRDW Q4 (CI, 1.81 to 4.92), and a 3.5-fold increased odds of MT was associated with aRDW Q5 (CI, 2.70 to 5.83). aRDW independently predicted MT, suggesting that elevated aRDW is an indicator of major hemorrhage in trauma patients. The association between aRDW and mortality in trauma patients may be explained by acute hemorrhage rather than chronic health status.

[Problem of intraoperative hemotransfusion]

MATERIALS AND METHODS

We studied 66 patients (males aged 39.5 +/- 5.3) with hemorrhagic shock II. Gas composition of arterial and venous blood and a detailed analysis of the blood were studied twice (before and after hemotransfusion).

RESULTS

We found that a low-volume (up to 2 doses) transfusion of erythrocyte mass with terms of storage up to 3 days, held after bleeding stop and hypovolemia correction, is the most effective treatment for hemorrhagic shock II.

CONCLUSIONS

Substitution therapy in operating room does not contribute oxygen transfering in tissues and inhibits stimulation of the bone marrow due to hypoxia. Thus the substitution therapy is an aggravating factor when the bleeding stopped, but hypovolemia not eliminated.

[Clinical effects of packed red blood cells transfusion according to storage life and time of transfusion]

It was studied 66 males aged 39.5±5.3 years with hemorrhagic shock II degree. Gas composition of arterial and venous blood was studied twice (before and after transfusion). It was revealed that succinct transfusion of packed red blood cells (to 2 doses) with storage life to 3 days after bleeding stop and hypovolemia filling is the most effective correction of hemorrhagic shock II degree. Replacement therapy in operating room in condition of stopped bleeding and unrepaired hypovolemia is burdening factor because it does not conducive to transfer of oxygen at the tissue level and inhibits stimulation of bone marrow in response to hypoxia.

[Association of cardiovascular system and endothelial dysfunction indicators in patients with hemorrhagic shock]

Endothelial dysfunction is a universal mechanism of pathogenesis of many critical conditions. Goal of the study was to assess a relation of cardiovascular system and endothelial dysfunction indicators in patients with hemorrhagic shock.

MATERIALS AND METHODS

17 patients with hemorrhagic shock 3 were involved in the study. All patients received infusion therapy, artificial lung ventilation after tracheal intubation and symptomatic treatment in prehospital period. Common volume of blood loose was 2900 +/- 200 mL. The patients received infusion, transfusion, inotrope, antibacterial, respiratory and symptomatic therapy in ICU after surgical treatment. Cardio-vascular system parameters were assessed by Tischenko method of integral reography. Number of red cells, hemoglobin, lactate, endotelin-1 and Wb-factor of venous blood were studied before surgery, in 12 and in 24 hours after. Morphological study of the omentumbiopsy was carried out.

RESULTS

Performed correlation analysis showed statistically significant relations of cardiovascular system and endothelial dysfunction indicators in patients with hemorrhagic shock. Endothelial dysfunction occurs in patients with hemorrhagic shock 3. The endothelial dysfunction correlates with parameters of cardio-vascular system and tissue perfusion.

Electroacupuncture improves gut barrier dysfunction in prolonged hemorrhagic shock rats through vagus anti-inflammatory mechanism

AIM: To investigate whether electroacupuncture (EA) at Zusanli (ST36) prevents intestinal barrier and remote organ dysfunction following prolonged hemorrhagic shock through a vagus anti-inflammatory mechanism.

METHODS: Sprague-Dawley rats were subjected to about 45% of total blood volume loss followed by delayed fluid replacement (DFR) with Ringer lactate 3h after hemorrhage. In a first study, rats were randomly divided into six groups: (1) EAN: EA at non-channel acupoints followed by DFR; (2) EA: EA at ST36 after hemorrhage followed by DFR; (3) VGX/EA: vagotomy (VGX) before EA at ST36 and DFR; (4) VGX/EAN: VGX before EAN and DFR; (5) α-bungarotoxin (α-BGT)/EA: intraperitoneal injection of α-BGT before hemorrhage, followed by EA at ST36 and DFR; and (6) α-BGT/EAN group: α-BGT injection before hemorrhage followed by EAN and DFR. Survival and mean arterial pressure (MAP) were monitored over the next 12 h. In a second study, with the same grouping and treatment, cytokine levels in plasma and intestine, organ parameters, gut injury score, gut permeability to 4 kDa FITC-dextran, and expression and distribution of tight junction protein ZO-1 were evaluated.

RESULTS: MAP was significantly lowered after blood loss; EA at ST36 improved the blood pressure at corresponding time points 3 and 12 h after hemorrhage. EA at ST36 reduced tumor necrosis factor-α and interleukin (IL)-6 levels in both plasma and intestine homogenates after blood loss and DFR, while vagotomy or intraperitoneal injection of α-BGT before EA at ST36 reversed its anti-inflammatory effects, and EA at ST36 did not influence IL-10 levels in plasma and intestine. EA at ST36 alleviated the injury of intestinal villus, the gut injury score being significantly lower than that of EAN group (1.85 ± 0.33 vs 3.78 ± 0.59, P < 0.05). EA at ST36 decreased intestinal permeability to FITC-dextran compared with EAN group (856.95 ng/mL ± 90.65 ng/mL vs 2305.62 ng/mL ± 278.32 ng/mL, P < 0.05). EA at ST36 significantly preserved ZO-1 protein expression and localization at 12 h after hemorrhage. However, EA at non-channel acupoints had no such effect, and abdominal vagotomy and α-BGT treatment could weaken or eliminate the effects of EA at ST36. Besides, EA at ST36 decreased blood aminotransferase, MB isoenzyme of creatine kinase and creatinine vs EAN group at corresponding time points. At the end of 12-h experiment, the survival rate of the EA group was significantly higher than that of the other groups.

CONCLUSION: EA at ST36 attenuates the systemic inflammatory response, protects intestinal barrier integrity, improves organ function and survival rate after hemorrhagic shock via activating the cholinergic anti-inflammatory mechanism.

Effects of biliverdin administration on acute lung injury induced by hemorrhagic shock and resuscitation in rats

Hemorrhagic shock and resuscitation induces pulmonary inflammation that leads to acute lung injury. Biliverdin, a metabolite of heme catabolism, has been shown to have potent cytoprotective, anti-inflammatory, and anti-oxidant effects. This study aimed to examine the effects of intravenous biliverdin administration on lung injury induced by hemorrhagic shock and resuscitation in rats. Biliverdin or vehicle was administered to the rats 1 h before sham or hemorrhagic shock-inducing surgery. The sham-operated rats underwent all surgical procedures except bleeding. To induce hemorrhagic shock, rats were bled to achieve a mean arterial pressure of 30 mmHg that was maintained for 60 min, followed by resuscitation with shed blood. Histopathological changes in the lungs were evaluated by histopathological scoring analysis. Inflammatory gene expression was determined by Northern blot analysis, and oxidative DNA damage was assessed by measuring 8-hydroxy-2′ deoxyguanosine levels in the lungs. Hemorrhagic shock and resuscitation resulted in prominent histopathological damage, including congestion, edema, cellular infiltration, and hemorrhage. Biliverdin administration prior to hemorrhagic shock and resuscitation significantly ameliorated these lung injuries as judged by histopathological improvement. After hemorrhagic shock and resuscitation, inflammatory gene expression of tumor necrosis factor-α and inducible nitric oxide synthase were increased by 18- and 8-fold, respectively. Inflammatory gene expression significantly decreased when biliverdin was administered prior to hemorrhagic shock and resuscitation. Moreover, after hemorrhagic shock and resuscitation, lung 8-hydroxy-2' deoxyguanosine levels in mitochondrial DNA expressed in the pulmonary interstitium increased by 1.5-fold. Biliverdin administration prior to hemorrhagic shock and resuscitation decreased mitochondrial 8-hydroxy-2' deoxyguanosine levels to almost the same level as that in the control animals. We also confirmed that biliverdin administration after hemorrhagic shock and resuscitation had protective effects on lung injury. Our findings suggest that biliverdin has a protective role, at least in part, against hemorrhagic shock and resuscitation-induced lung injury through anti-inflammatory and anti-oxidant mechanisms.

Ethanol consumption impairs the hemodynamic response to hemorrhagic shock in rats

Alcohol intoxication can exacerbate hemodynamic instability following hemorrhagic shock. Impairment of hormonal, neurohumoral, and immune responses can contribute to such instability; however, the relationship between blood alcohol levels and the progression of hemorrhagic shock accompanied with these responses has not been clearly demonstrated. Herein, we examined this relationship in rats treated with various dose of alcohol. After oral administration of alcohol and then hemorrhage, the recovery of mean blood pressure (MBP); increase in plasma level of norepinephrine, epinephrine, and vasopressin; and survival interval decreased in a dose-dependent manner as the blood alcohol level increased. There were no significant differences in the production of proinflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β among the groups. The present results demonstrated alcohol aggravates hemorrhagic shock in a dose-dependent manner not by alerting the immune response, but by suppressing hormonal and neurohumoral responses, thereby inhibiting hemodynamic autoregulation and shortening the survival interval.