Shock Resuscitation Research Articles

Dexmedetomidine improves acute lung injury by activating autophagy in a rat hemorrhagic shock and resuscitation model

Dexmedetomidine (DEX) can reduce lung injury in a hemorrhagic shock (HS) resuscitation (HSR) model in rats by inhibiting inflammation. Here, we aimed to investigate if these effects of DEX are due to autophagy activation. Therefore, we established HSR rat models and divided them into four groups. HS was induced using a blood draw. The rats were then resuscitated by reinjecting the drawn blood and saline. The rats were sacrificed 24 h after resuscitation. Lung tissues were harvested for histopathological examination, determination of wet/dry lung weight ratio, and detection of the levels of autophagy-related marker proteins LC3, P62, Beclin-1, and the ATG12-ATG5 conjugate. The morphological findings of hematoxylin and eosin staining in lung tissues and the pulmonary wet/dry weight ratio showed that lung injury improved in HSR + DEX rats. However, chloroquine (CQ), an autophagy inhibitor, abolished this effect. Detecting the concentration of autophagy-related proteins showed that DEX administration increased LC3, ATG12-ATG5, and Beclin-1 expression and decreased P62 expression. The expression levels of these proteins were similar to those in the HSR group after CQ + DEX administration. In summary, DEX induced autophagic activation in an HSR model. These findings suggest that DEX administration partially ameliorates HSR-induced lung injury via autophagic activation.

SHock-INduced Endotheliopathy (SHINE): A mechanistic justification for viscoelastography-guided resuscitation of traumatic and non-traumatic shock.

Irrespective of the reason for hypoperfusion, hypocoagulable and/or hyperfibrinolytic hemostatic aberrancies afflict up to one-quarter of critically ill patients in shock. Intensivists and traumatologists have embraced the concept of SHock-INduced Endotheliopathy (SHINE) as a foundational derangement in progressive shock wherein sympatho-adrenal activation may cause systemic endothelial injury. The pro-thrombotic endothelium lends to micro-thrombosis, enacting a cycle of worsening perfusion and increasing catecholamines, endothelial injury, de-endothelialization, and multiple organ failure. The hypocoagulable/hyperfibrinolytic hemostatic phenotype is thought to be driven by endothelial release of anti-thrombogenic mediators to the bloodstream and perivascular sympathetic nerve release of tissue plasminogen activator directly into the microvasculature. In the shock state, this hemostatic phenotype may be a counterbalancing, yet maladaptive, attempt to restore blood flow against a systemically pro-thrombotic endothelium and increased blood viscosity. We therefore review endothelial physiology with emphasis on glycocalyx function, unique biomarkers, and coagulofibrinolytic mediators, setting the stage for understanding the pathophysiology and hemostatic phenotypes of SHINE in various etiologies of shock. We propose that the hyperfibrinolytic phenotype is exemplified in progressive shock whether related to trauma-induced coagulopathy, sepsis-induced coagulopathy, or post-cardiac arrest syndrome-associated coagulopathy. Regardless of the initial insult, SHINE appears to be a catecholamine-driven entity which early in the disease course may manifest as hyper- or hypocoagulopathic and hyper- or hypofibrinolytic hemostatic imbalance. Moreover, these hemostatic derangements may rapidly evolve along the thrombohemorrhagic spectrum depending on the etiology, timing, and methods of resuscitation. Given the intricate hemochemical makeup and changes during these shock states, macroscopic whole blood tests of coagulative kinetics and clot strength serve as clinically useful and simple means for hemostasis phenotyping. We suggest that viscoelastic hemostatic assays such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are currently the most applicable clinical tools for assaying global hemostatic function-including fibrinolysis-to enable dynamic resuscitation with blood products and hemostatic adjuncts for those patients with thrombotic and/or hemorrhagic complications in shock states.

Intra-renal microcirculatory alterations on non-traumatic hemorrhagic shock induced acute kidney injury in pigs.

Acute kidney injury (AKI) is frequently seen in patients with hemorrhagic shock due to hypotension, tissue hypoxia, and inflammation despite adequate resuscitation. There is a lack of information concerning the alteration of renal microcirculation and perfusion during shock and resuscitation. The aim of this study was to investigate the possible role of renal microcirculatory alterations on development of renal dysfunction in a pig model of non-traumatic hemorrhagic shock (HS) induced AKI.Fully instrumented female pigs were divided into the two groups as Control (n = 6) and HS (n = 11). HS was achieved by withdrawing blood until mean arterial pressure (MAP) reached around 50 mmHg. After an hour cessation period, fluid resuscitation with balanced crystalloid was started for the duration of 1h. The systemic and renal hemodynamics, renal microcirculatory perfusion (contrast-enhanced ultrasound (CEUS)) and the sublingual microcirculation were measured.CEUS peak enhancement was significantly increased in HS during shock, early-, and late resuscitation indicating perfusion defects in the renal cortex (p < 0.05 vs. baseline, BL) despite a stable renal blood flow (RBF) and urine output. Following normalization of systemic hemodynamics, we observed persistent hypoxia (high lactate) and high red blood cell (RBC) velocity just after initiation of resuscitation resulting in further endothelial and renal damage as shown by increased plasma sialic acid (p < 0.05 vs. BL) and NGAL levels. We also showed that total vessel density (TVD) and functional capillary density (FCD) were depleted during resuscitation (p < 0.05).In this study, we showed that the correction of systemic hemodynamic variables may not be accompanied with the improvement of renal cortical perfusion, intra-renal blood volume and renal damage following fluid resuscitation. We suggest that the measurement of renal injury biomarkers, systemic and renal microcirculation can be used for guiding to the optimization of fluid therapies.

Determining the top research priorities in UK prehospital critical care: a modified Delphi study

BackgroundPrehospital critical care is a rapidly evolving field. There is a paucity of evidence relating to its practice, with limited progress in answering those research questions identified over a decade...

Postinjury multiple organ failure in polytrauma: more frequent and potentially less deadly with less crystalloid

BackgroundRecently, retrospective registry-based studies have reported the decreasing incidence and increasing mortality of postinjury multiple organ failure (MOF). We aimed to describe the current epidemiology of MOF following the introduction of haemostatic resuscitation.MethodsA 10-year prospective cohort study was undertaken at a Level-1 Trauma Centre-based ending in December 2015. Inclusion criteria age ≥ 16 years, Injury Severity Score (ISS) > 15, Abbreviated Injury Scale (AIS) Head < 3 and survived > 48 h. Demographics, physiological and shock resuscitation parameters were collected. The primary outcome was MOF defined by a Denver Score > 3. Secondary outcomes: intensive care unit length of stay (ICU LOS), ventilation days and mortality.ResultsThree hundred and forty-seven patients met inclusion criteria (age 48 ± 20; ISS 30 ± 11, 248 (71%) were males and 23 (6.6%) patients died. The 74 (21%) MOF patients (maximum Denver Score: 5.5 ± 1.8; Duration; 5.6 ± 5.8 days) had higher ISS (32 ± 11 versus 29 ± 11) and were older (54 ± 19 versus 46 ± 20 years) than non-MOF patients. Mean daily Denver scores adjusted for age, sex, MOF and ISS did not change over time. Crystalloid usage decreased over the 10-year period (p value < 0.01) and PRBC increased (p value < 0.01). Baseline cumulative incidence of MOF at 28 days was 9% and competing risk analyses showed that incidence of MOF increased over time (subdistribution hazard ratio 1.14, 95% CI 1.04 to 1.23, p value < 0.01). Mortality risk showed no temporal change. ICU LOS increased over time (subdistribution hazard ratio 0.95, 95% CI 0.92 to 0.98, p value < 0.01). Ventilator days increased over time (subdistribution hazard ratio 0.94, 95% CI 0.9 to 0.97, p value < 0.01).ConclusionThe epidemiology of MOF continues to evolve. Our prospective cohort suggests an ageing population with increasing incidence of MOF, particularly in males, with little changes in injury or shock parameters, who are being resuscitated with less crystalloids, stay longer on ICU without improvement in survival.

Correction to: Trauma emergency thoracotomy for resuscitation in shock—a multi-centre evaluation of current UK practice of pre-hospital and emergency department resuscitative thoracotomy in trauma

Correction to: Trauma emergency thoracotomy for resuscitation in shock—a multi-centre evaluation of current UK practice of pre-hospital and emergency department resuscitative thoracotomy in trauma

Acute puerperal uterine inversion

Uterine inversion is often accompanied by postpartum hemorrhage and hypovolemic shock. Morbidity and mortality occur in 41% of cases. Early recognition and management are of utmost importance. Successful treatment depends on timely recognition. Management should include resuscitation of maternal hypovolemic shock and repositioning of the inverted uterine fundus. Uterine inversion is a rare but potentially life-threatening obstetric emergency.

The Whole Story: A Comprehensive Review of Whole Blood Resuscitation for Hemorrhagic Shock

The Whole Story: A Comprehensive Review of Whole Blood Resuscitation for Hemorrhagic Shock

Clinical parameter-guided initial resuscitation in adult patients with septic shock: A systematic review and network meta-analysis.

To identify the most useful tissue perfusion parameter for initial resuscitation in sepsis/septic shock adults using a network meta-analysis. We searched major databases until December 2022 for randomized trials comparing four tissue perfusion parameters or against usual care. The primary outcome was short-term mortality up to 90 days. The Confidence in Network Meta-Analysis web application was used to assess the quality of evidence. Seventeen trials were identified. Lactate-guided therapy (risk ratios, 0.59; 95% confidence intervals [0.45-0.76]; high certainty) and capillary refill time-guided therapy (risk ratios, 0.53; 95% confidence intervals [0.33-0.86]; high certainty) were significantly associated with lower short-term mortality compared with usual care, whereas central venous oxygen saturation-guided therapy (risk ratio, 1.50; 95% confidence intervals [1.16-1.94]; moderate certainty) increased the risk of short-term mortality compared with lactate-guided therapy. Lactate or capillary refill time-guided initial resuscitation for sepsis/septic shock patients may decrease short-term mortality. More research is essential to personalize and optimize treatment strategies for septic shock resuscitation.

Fluid Creep in ARDS after Shock Resuscitation of Trauma, Burns, Sepsis, and Acute Pancreatitis Patients: How Much, Where, and How to Find it?

I peer-reviewed this article with great interest but was rejected by the editor

Correlation between Perfusion Index and Lactate Level in Critically Ill Patients

Background: During shock resuscitation, early detection of tissue hypoperfusion would guide physician to actively manage for the better outcome. Serum lactate is commonly used but it needs blood sampling and obtains intermittent data. Perfusion index (PI) analyzed from pulse-oximetry signal is a non-invasive and continuous monitoring for peripheral tissue perfusion. Previous studies have shown correlations between PI and microcirculation parameters in critically ill patients; however, limited data is available. Objective: To investigate the correlation between PI and lactate level in critically ill patients. Materials and Methods: The present study was a prospective observational study at the surgical intensive care unit of King Chulalongkorn Memorial Hospital (KCMH). All critically ill patients having tissue hypoperfusion and serum lactate of 2 mmol/L or greater were enrolled. PI was measured by MasimoRadical-7®PulseCO-Oximeter® and recorded values simultaneously with serum lactate at 0, 2, 6, and 24-hours during resuscitation. Results: Of the 42 patients, the authors found a significant correlation between PI and lactate level at 0 and 2-hours (r=–0.397, p=0.009 and r=–0.311, p=0.045, respectively). The change in PI also significantly correlated with lactate clearance at first 6-hours of resuscitation (r=0.444, p=0.003 at 0 to 2-hour and r=0.370, p=0.017 at 2 to 6-hours). Twenty-four patients or 57% had lactate clearance of 10% or more within 2-hours, whereas 18 patients (42.8%) did not. The cut-off value of increasing in PI of less than 0.86 predicted patients who were not lactate clearance at 2-hours, (sensitivity 88.9%, specificity 54.2%, AUC 0.699, 95% CI 0.54 to 0.86, p=0.029). Conclusion: PI may have value to adjunct continuous monitoring for peripheral perfusion during early resuscitation by using concurrently with serum lactate. Increase in PI of less than 0.86 within 2-hours should prompt the physician to manage it further. Keywords: Lactate; Perfusion index; PI; Peripheral tissue perfusion; Microcirculatory monitoring

1034: DOES POCUS AFFECT FLUID RESUSCITATION IN SEPTIC SHOCK? A RETROSPECTIVE OBSERVATIONAL STUDY

Introduction: Point of care ultrasound (POCUS) may guide intravenous fluids (IVF) resuscitation in septic shock to prevent inadvertent hypovolemia and death. The primary study objective is to determine if total IVF volume differs for Emergency Department (ED) septic shock patients receiving POCUS vs. no POCUS. Secondary objectives included new oxygen requirement and overall mortality. Methods: We conducted a retrospective observational cohort study from 7/1/2018 – 8/31/2021 of atraumatic adult patients who presented to the ED septic shock. We agreed upon a priori outcome variables and defined septic shock as lactate ≥4 and hypotension (SBP < 90 or MAP < 65). A sample size of 300 patients would provide 85% power to detect an IVF difference of 500 mls between POCUS and non-POCUS cohorts. Data is reported as frequencies, median(IQR) and associations from bivariate logistic models. Results: A total of 304 patients met criteria and 26% (78/304) used cardiopulmonary POCUS. There were no statistical differences between POCUS vs. non-POCUS cohorts for: age, race, gender or co-morbidities. History of CHF and severe renal disease was present in 42% of POCUS group and 29% of non-POCUS group. The POCUS vs. non-POCUS cohorts had statistically significant differences for the following variables: higher median lactate (6.7 [IQR 5.2-8.7] vs. 5.6 [IQR 4.7-7.4], p=0.003), lower systolic blood pressure (77.5 (IQR 61-86] vs. 85.0 (IQR 73-95), p< 0.001), more vasopressor use (51% vs. 34%, p=0.006), and more positive pressure ventilation (38% vs. 24%, p=0.017). However, there were no statistical significance in patient outcomes between POCUS and non-POCUS cohorts including total IVF volume ml/kg (33.02 vs. 32.1, p= 0.47), new oxygen requirement (68% [53/78) vs. 59% [133/226], p=.16), ED death (3% vs. 4%, p=0.15), or hospital death (31% vs. 27%, p=0.48). Similar distributions of lactate, total fluids, and vasopressors were found in CHF and severe renal disease subsets. Conclusions: POCUS was more likely to be used in ED septic patients with higher lactate, lower blood pressure, vasopressor use, and in those requiring mechanical ventilation. There were no differences in total IVF received, new oxygen requirement, and mortality in the POCUS group compared to non-POCUS group.

1172: EVALUATION OF SHELF-STABLE BLOOD PRODUCTS FOR RESUSCITATION IN A CANINE MODEL OF HEMORRHAGIC SHOCK

Introduction: Hemorrhagic shock is a major cause of morbidity and mortality in trauma patients. Current resuscitation methods use blood products that require temperature control and have a limited lifespan, which present significant limitations for use in rural areas and combat zones. This study examined whether shelf stable blood product resuscitation strategies leveraging freeze-dried plasma (FDP), hemoglobin based oxygen carrier (HBOC), and lyophilized platelets (LP) provide an alternative to conventional resuscitation strategies in a canine model. We hypothesized that a combination of HBOC and FDP with or without LP would be non-inferior to chilled whole blood (CWB) for hemorrhagic shock resuscitation. Methods: Seven dogs were anesthetized and subjected to controlled hemorrhage of up to 40% of their blood volume (T0) over one hour to achieve a mean arterial blood pressure of 35-50 mmHg. They were maintained in shock for 45 minutes and were then randomized to receive: CWB, FDP+HBOC, or FDP+HBOC+LP over 30 minutes (T105-135). Citrated blood was collected at T0, T105, T135, and T180 for thromboelastography (TEG 5000). Samples were run in duplicates with kaolin activation to measure reaction time (r), kinetic time (k), alpha angle (alpha), and maximum amplitude (MA). Between-group comparisons were performed using a Kruskal-Wallis ANOVA and a Bonferroni correction. Results are reported as mean +/- standard deviation. Results: There was no difference in baseline parameters between groups or in TEG values between groups at the end of shock T0 and T105. There was a difference in alpha and MA between groups at T135 (p= 0.02 for both) and T180 (p=0.02 and 0.002, respectively). Specifically, alpha and MA were lower in the FDP+HBOC+LP group (alpha: 54.9 +/- 6.6 deg; MA: 43.5 +/- 11.5 mm) than in the CWB group (alpha: 64.4 +/- 5.2 deg; MA: 58.2 +/- 5.1 mm). There was no difference in r, alpha, and k between groups at any time point. Conclusions: In this canine model of controlled hemorrhage, TEG parameters between FDP+HBOC and CWB were not different. We demonstrated evidence of reduced coagulation function in FDP+HBOC+LP. The biological relevance of those findings should be determined in an uncontrolled hemorrhage model. Resuscitation with shelf-stable products appeared safe and satisfactory in this model.

Exploring the relationship between capillary refill time, skin blood flow and microcirculatory reactivity during early resuscitation of patients with septic shock: a pilot study.

Capillary refill time (CRT), a costless and widely available tool, has emerged as a promising target to guide septic shock resuscitation. However, it has yet to gain universal acceptance due to its potential inter-observer variability. Standardization of CRT assessment may minimize this problem, but few studies have compared this approach with techniques that directly assess skin blood flow (SBF). Our objective was to determine if an abnormal CRT is associated with impaired SBF and microvascular reactivity in early septic shock patients. Twelve septic shock patients were subjected to multimodal perfusion and hemodynamic monitoring for 24h. Three time-points (0, 1, and 24h) were registered for each patient. SBF was measured by laser doppler. We performed a baseline SBF measurement and two microvascular reactivity tests: one with a thermal challenge at 44°C and other with a vascular occlusion test. Ten healthy volunteers were evaluated to obtain reference values. The patients (median age 70years) exhibited a 28-day mortality of 50%. Baseline CRT was 3.3 [2.7-7.3] seconds. In pooled data analysis, abnormal CRT presented a significantly lower SBF when compared to normal CRT [44 (13.3-80.3) vs 193.2 (99.4-285) APU, p = 0.0001]. CRT was strongly associated with SBF (R2 0.76, p < 0.0001). An abnormal CRT also was associated with impaired thermal challenge and vascular occlusion tests. Abnormal CRT values observed during early septic shock resuscitation are associated with impaired skin blood flow, and abnormal skin microvascular reactivity. Future studies should confirm these results.

Fluids or vasopressors for the initial resuscitation of septic shock.

Intravenous fluid resuscitation is recommended first-line treatment for sepsis-associated hypotension and/or hypoperfusion. The rationale is to restore circulating volume and optimize cardiac output in the setting of shock. Nonetheless, there is limited high-level evidence to support this practice. Over the past decade emerging evidence of harm associated with large volume fluid resuscitation among patients with septic shock has led to calls for a more conservative approach. Specifically, clinical trials undertaken in Africa have found harm associated with initial fluid resuscitation in the setting of infection and hypoperfusion. While translating these findings to practice in other settings is problematic, there has been a re-appraisal of current practice with some recommending earlier use of vasopressors rather than repeated fluid boluses as an alternative to restore perfusion in septic shock. There is consequently uncertainty and variation in practice. The question of fluids or vasopressors for initial resuscitation in septic shock is the subject of international multicentre clinical trials.

Advantages of pyruvate-based fluids in preclinical shock resuscitation-A narrative review.

This review focuses on the innate beneficial effects of sodium pyruvate-based fluids, including pyruvate in intravenous solutions, oral rehydration solutions, and peritoneal dialysis solutions, on shock resuscitation with various animal models relative to current commercial fluids over the last two decades. Due to its superior pharmacological properties, pyruvate effectively sustains cytosolic glycolytic pathways and mitochondrial oxidative phosphorylation by restoration of redox potentials and reactivation of pyruvate dehydrogenase in hypoxia, even anoxia, and diabetes, reversing the Warburg effect and diabetic glucometabolic aberration. Pyruvate has been demonstrated to protect against multiorgan dysfunction and metabolic disturbance in numerous preclinical studies with various pathogenic injuries. The unique features of pyruvate potential clinical benefits encompass to efficiently correct lethal lactic acidosis via metabolically rapid consumption of intracellular [H+] and robustly protect multiorgan metabolism and function, particularly visceral organs in addition to the heart and brain, significantly prolonging survival in various animal models. Pyruvate protection of red blood cell function and preservation of the partial pressure of arterial oxygen should be highly concerned in further studies. Pyruvate is much advantageous over existing anions such as acetate, bicarbonate, chloride, and lactate in commercial fluids. Pyruvate-based fluids act as a therapeutic agent without causing iatrogenic resuscitation injury in addition to being a volume expander, indicating a potential novel generation of resuscitation fluids, including crystalloids and colloids. Pyruvate-based fluids have an enormous potential appeal for clinicians who face the ongoing fluid debate to readily select as the first resuscitation fluid. Clinical trials with pyruvate-based fluids in shock resuscitation are urgently warranted.

Effect of albumin solutions on endothelial oxidant injury: A microfluidic study

BackgroundStudies have suggested a beneficial effect of early plasma-based resuscitation in patients following trauma-hemorrhagic shock. The underlying mechanism(s) are unknown but may be owing to protective effects of plasma components on the endothelium and its glycocalyx layer. Albumin, the major protein in plasma, influences vascular integrity and has antioxidant properties in vivo. Sphingosine 1-phosphate is a bioactive sphingolipid with diverse signaling functions, which include endothelial barrier protection in part owing to preservation of the glycocalyx. Sphingosine 1-phosphate is bound mainly to albumin and high-density lipids in the plasma. Debate continues about the beneficial effect of albumin solutions in shock resuscitation. Pharmacologic preparations may modify constituents of albumin solutions for clinical use. We examined the relative effects of sphingosine 1-phosphate concentrations in albumin solutions on the endothelial-glycocalyx barrier in an in vitro microfluidic platform. MethodsEndothelial cell monolayers were established in microfluidic perfusion devices and exposed to control or biomimetic shock conditions followed by 5% plasma or different albumin solutions ± exogenous sphingosine 1-phosphate perfusion. Biomarkers of endothelial and glycocalyx activation, damage, and oxidant injury were then determined. ResultsEndothelial cell and glycocalyx barriers were damaged after biomimetic shock conditions. Plasma and sphingosine 1-phosphate loaded albumin solutions protected against barrier injury. Modest protective effects were noted with albumin alone; the efficacy varied with sphingosine 1-phosphate content of the albumin solution. ConclusionThe protective effect of albumin on the endothelia-glycocalyx barrier against oxidant injury was dependent on its sphingosine 1-phosphate concentration. Our data may help explain the discrepancies regarding the effectiveness of albumin solutions in shock resuscitation.

Dual Input Fuzzy Logic Controllers for Closed Loop Hemorrhagic Shock Resuscitation

Hemorrhage remains a leading cause of preventable death in emergency situations, including combat casualty care. This is partially due to the high cognitive burden that constantly adjusting fluid resuscitation rates can require, especially in austere or mass casualty situations. Closed-loop control systems have the potential to simplify hemorrhagic shock resuscitation if properly tuned for the application. We have previously compared 4 different controller types using a hardware-in-loop test platform that simulates hemorrhagic shock conditions, and we found that a dual input—(1) error from target and (2) rate of error change—fuzzy logic (DFL) controller performed best. Here, we highlight a range of DFL designs to showcase the tunability the controller can have for different hemorrhage scenarios. Five different controller setups were configured with different membership function logic to create more and less aggressive controller designs. Overall, the results for the different controller designs ranged from reaching the setup rapidly but often overshooting the target to more conservatively approaching the target, resulting in not reaching the target during high active hemorrhage rates. In conclusion, DFL controllers are well-suited for hemorrhagic shock resuscitation and can be tuned to meet the response rates set by clinical practice guidelines for this application.

Fluid Resuscitation in Patients Presenting with Sepsis: Current Insights.

Intravenous (IV) fluid resuscitation is a key component of the initial resuscitation of septic shock, with international consensus guidelines suggesting the administration of at least 30mL/kg of isotonic crystalloid fluid. The rationale is to restore circulating fluid volume and optimise stroke volume. It is acknowledged that there is a paucity of high-level evidence to support this strategy, with most studies being observational or retrospective in design. In the past decade, evidence has emerged that a large positive fluid balance is associated with worse outcomes among patients with septic shock in intensive care who have already received initial resuscitation. Randomised trials undertaken in low-income countries have found increased mortality among patients with sepsis and hypoperfusion administered a larger fluid volume as part of initial resuscitation, however, translating these findings to other settings is not possible. This uncertainty has led to variation in practice with some advocating a more conservative fluid strategy coupled with the earlier introduction of vasopressors for haemodynamic support. This question is the subject of several ongoing clinical trials. This article summarises the current state of the evidence for IV fluid resuscitation in septic shock and provides guidance for practitioners in the face of our evolving understanding of this important area.

Trauma emergency thoracotomy for resuscitation in shock—a multi-centre evaluation of current UK practice of pre-hospital and emergency department resuscitative thoracotomy in trauma

Abstract Background Resuscitative thoracotomy (RT) in traumatic cardiac arrest, in particular for penetrating trauma features within several national guidelines. However, evidence surrounding its practice is poor, consisting of predominantly small-scale observational studies. Survival is generally poor, estimated at 3–13%, with better outcomes in penetrating trauma. There is no national RT database and the Trauma Audit Research Network data misses those who have died pre-hospital. It is important that a more in-depth and accurate national picture of thoracotomy practice is developed nationally to guide future practice. Traumatic emergency thoracotomy for resuscitation in shock (TETRiS) is a multi-centre, prospective and observational evaluation of current RT practice in the UK. Aims and objectives The aim of TETRiS is to evaluate the pathway of care for RT patients within the UK. This will be undertaken over a period of 12 months. This project will evaluate thoracotomies undertaken both pre-hospital and in emergency departments, examining various parameters including frequency, who performs the procedure, clinical indications, time from injury to initiation, mechanism of injury, injuries identified, interventions performed and patient outcomes. Methods This project is being conducted as a collaboration between the National Trauma Research and Innovation Collaborative, the Pre-Hospital Trainee Operated Research Network, the Trainee Emergency Research Network and the National HEMS Research and Audit Forum (NHRAF). All UK HEMS, helicopter emergency medicine services and major trauma centre (MTCs) nationally have been recruited, with site investigators identified within each participating unit. Inclusion criteria: All patients undergoing RT, pre-hospital or in an MTC emergency department will be included.