The influence of needleless connectors and inserted catheters on flow rates through vascular introducer sheaths

SummaryA vascular introducer sheath is often used for rapid volume replacement. However, common manipulations such as the addition of needleless connectors to infusion ports and the insertion of catheters or other devices through the introducer sheath may impede flow. In this study we utilised a rapid infuser to deliver room-temperature normal saline through two introducer sheath configurations with and without the addition of needleless connectors and the placement of catheters through the introducer sheaths. The maximal flow rate delivered by the rapid infuser was 1000 mL/min, which was observed with both introducer sheath sizes tested without additional resistive elements. However, with the addition of a needleless connector, flow rates through the introducer sheaths were substantially lower (64 (standard deviation (SD) 6) mL/min and 61 (SD 7) mL/min for the 8.5 Fr and 9 Fr introducers, respectively). Flow rates were also reduced when catheters were placed within the sheaths (298 (SD 9) mL/min with the 7 Fr catheter and 74 (SD 9) mL/min with the 8 Fr catheter placed in an 8.5 Fr sheath; 649 (SD 6) mL/min with the 7 Fr catheter and 356 (SD 14) mL/min with the 8 Fr catheter placed in the 9 Fr sheath). These findings indicated that both needleless connectors and the placement of catheters through vascular introducer sheaths substantially reduced potential flow rates. Even 'large' vascular introducer sheaths capable of delivering high flow rates could be rendered minimally effective for rapid fluid administration when used in this way. Clinicians should consider these impediments to flow when rapid fluid administration is required, and obtain alternative vascular access if necessary.

TiME OUT: Time-specific machine-learning evaluation to optimize ultramassive transfusion

BACKGROUND

Ultramassive transfusion (UMT) is a resource-demanding intervention for trauma patients in hemorrhagic shock, and associated mortality rates remains high. Current research has been unable to identify a transfusion ceiling or point where UMT transitions from lifesaving to futility. Furthermore, little consideration has been given to how time-specific patient data points impact decisions with ongoing high-volume resuscitation. Therefore, this study sought to use time-specific machine learning modeling to predict mortality and identify parameters associated with survivability in trauma patients undergoing UMT.

METHODS

A retrospective review was conducted at a Level I trauma (2018-2021) and included trauma patients meeting criteria for UMT, defined as ≥20 red blood cell products within 24 hours of admission. Cross-sectional data were obtained from the blood bank and trauma registries, and time-specific data were obtained from the electronic medical record. Time-specific decision-tree models predicating mortality were generated and evaluated using area under the curve.

RESULTS

In the 180 patients included, mortality rate was 40.5% at 48 hours and 52.2% overall. The deceased received significantly more blood products with a median of 71.5 total units compared with 55.5 in the survivors ( p < 0.001) and significantly greater rates of packed red blood cells and fresh frozen plasma at each time interval. Time-specific decision-tree models predicted mortality with an accuracy as high as 81%. In the early time intervals, hemodynamic stability, undergoing an emergency department thoracotomy, and injury severity were most predictive of survival, while, in the later intervals, markers of adequate resuscitation such as arterial pH and lactate level became more prominent.

CONCLUSION

This study supports that the decision of "when to stop" in UMT resuscitation is not based exclusively on the number of units transfused but rather the complex integration of patient and time-specific data. Machine learning is an effective tool to investigate this concept, and further research is needed to refine and validate these time-specific decision-tree models.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Utility of rotational thromboelastometry in the management of massive haemorrhage at a regional Australian hospital

BACKGROUND

Rotational thromboelastometry (ROTEM) allows targeted and individualised blood product replacement.

OBJECTIVES

The study aimed to determine the impact of ROTEM-guided transfusion on the clinical course of patients with acute massive haemorrhage in a regional Australian hospital.

METHODS/MATERIALS

A retrospective review of all patients with acute massive haemorrhage that compared the characteristics, blood product use, and clinical outcomes of patients with massive haemorrhage before and after the introduction of ROTEM-guided transfusion.

RESULTS

In per-protocol analysis, the 31/97 (32%) with ROTEM-guided transfusion used less packed red blood cells (median [interquartile range]: 6 [6-8] vs. 8 [6-12] units, p = 0.03) than patients whose transfusion was not ROTEM-guided. They were also less likely to receive fresh frozen plasma (2/31 [6%] vs. 45/66 [68%], p < 0.0001) or platelets (2/31 [6%] vs. 31/66 [47%], p < 0.0001); they were, however, more likely to receive fibrinogen products (26/31 [84%] vs. 38/66 [58%], p = 0.01). Patients receiving ROTEM-guided transfusion had lower in-hospital mortality (6/31 [19%] vs. 20/66 [30%], odds ratio 0.55 [95% confidence interval]: 0.20-1.55, p = 0.26) although this did not achieve statistical significance in this small cohort.

CONCLUSION

ROTEM-guided massive transfusion of patients with acute haemorrhage in this regional Australian hospital led to a reduction in packed red blood cell, fresh frozen plasma, and platelet utilisation and may also have reduced mortality.

Predictors of intraoperative massive transfusion in orthotopic liver transplantation

BACKGROUND

Although transfusion management has improved during the last decade, orthotopic liver transplantation (OLT) has been associated with considerable blood transfusion requirements which poses some challenges in securing blood bank inventories. Defining the predictors of massive blood transfusion before surgery will allow the blood bank to better manage patients' needs without delays. We evaluated the predictors of intraoperative massive transfusion in OLT.

STUDY DESIGN AND METHODS

Data were collected on patients who underwent OLT between 2007 and 2017. Repeat OLTs were excluded. Analyzed variables included recipients' demographic and pretransplant laboratory variables, donors' data, and intraoperative variables. Massive transfusion was defined as intraoperative transfusion of ≥10 units of packed red blood cells (RBCs). Statistical analysis was performed using SPSS version 17.0.

RESULTS

The study included 970 OLT patients. The median age of patients was 57 (range: 16-74) years; 609 (62.7%) were male. RBCs, thawed plasma, and platelets were transfused intraoperatively to 782 (80.6%) patients, 831 (85.7%) patients, and 422 (43.5%) patients, respectively. Massive transfusion was documented in 119 (12.3%) patients. In multivariate analysis, previous right abdominal surgery, the recipient's hemoglobin, Model for End Stage Liver Disease (MELD) score, cold ischemia time, warm ischemia time, and operation time were predictive of massive transfusion. There was a direct significant correlation between the number of RBC units transfused and plasma (Pearson correlation coefficient r = .794) and platelets (r = .65).

DISCUSSION

Previous abdominal surgery, the recipient's hemoglobin, MELD score, cold ischemia time, warm ischemia time, and operation time were predictive of intraoperative massive transfusion in OLT.

Incidence of Red Cell Antibody Formation Following Massive Transfusion Protocol: Experience of a Single Institution

BACKGROUND

Injured patients in hemorrhagic shock have a survival benefit with massive transfusion protocol (MTP). While there are many published studies on the transfusion management of massively bleeding patients, the risk of alloimmunization in patients that have received products during an MTP activation is relatively unknown. Therefore, we sought to determine the frequency of new antibody formation in MTP patients that received blood products from an uncrossmatched megapack.

MATERIALS AND METHODS

We conducted a retrospective data review of patients who underwent an MTP activation for trauma resuscitation between May 2014 and July 2020. Data were collected from patients who met the following criteria: MTP was activated, the patients received at least one unit of packed red blood cells, one unit of fresh frozen plasma, one unit of platelets, and had a repeat type and screen within 6 weeks of transfusion. These inclusion criteria resulted in 28 patients over the 6-year timeframe.

RESULTS

Overall, the risk of alloimmunization secondary to MTP is 3.6% in our trauma patient population. The newly developed antibodies post-MTP are considered clinically significant, meaning they can cause hemolysis if exposed to donor red blood cells containing those antigens.

DISCUSSION

Blood products should be given preferentially over crystalloids to acutely bleeding patients to prevent ischemic injury during an MTP activation despite the risk of alloimmunization. In our single-institution study, the alloimmunization rate in massive transfusions where patients receive uncrossmatched red blood cells is similar to those receiving crossmatched red blood cells.

Critical Care Length of Stay and Support Requirements for Patients Postpancreas Transplant

Introduction: Pancreas transplant is one of the UK's less commonly done solid abdominal organ transplants. The transplant is reputed for its high-risk postsurgical complications due to multiple patients, procedures, and immunological factors. For this reason, patients are habitually admitted to the intensive care unit for postlaparotomy care, physiological support, and graft function monitoring during their immediate postoperative course. Project Aim: This program evaluation analyzed the trend in critical care length of stay and organ support requirements for patients following whole pancreas transplantation. The aim was to use these baseline data as performance metrics to enable a safer transition and Plan-Do-Study-Act (PDSA) cycles in improving the delivery of enhanced recovery service. Design: A retrospective chart review was performed using records from Phillips IntelliSpace Critical Care and Anaesthesia system to evaluate the institutional outcomes of patients < 18 years admitted to intensive care following pancreas transplantation between January 1, 2018, and December 31, 2021. Islet-cell transplant recipients were excluded as there is a different postoperative recovery. Results: The data suggested that although patients require a higher level of observations, blood pressure management, blood gas, and glucose monitoring during their first week of transplant, these patients did not routinely require the full range of critical care support. Conclusion: The present evaluation reported the organ support requirements for these transplant recipients. The results will generate further interest in enhanced recovery and service evaluation projects to streamline the postoperative care of these patients from the operating theatre back to the transplant wards.

Pulse Pressure: A Predictor of Intervention in Blunt Abdominal Trauma

BACKGROUND

Patients with life-threatening hemorrhages due to blunt torso trauma are at a particularly high risk of being underdiagnosed. The pulse pressure (PP) starts narrowing down before the traditional parameters start changing, making it a useful tool for assessing and planning early intervention.

OBJECTIVE

To assess the utility of low PP in predicting massive transfusion (MT) or operative intervention in patients with isolated blunt abdominal trauma.

MATERIAL AND METHODS

A total of 186 patients were included. The PP and mean arterial pressure (MAP) were calculated. Vitals, PP, and MAP were monitored every 15 min during the first 6 h, then every 30 min during the next 6 h, and afterward, every 4 h until discharge. A Chi-square test and an independent t-test (as appropriate) were applied to compare variables with PP at the time of presentation. Differences were considered statistically significant at p-value ≤ 0.05.

RESULTS

A total of 55.9% of these patients had injuries due to road traffic accidents (RTA). Emergency operative intervention was provided to 26.3% of the patients. Death was 4.3%. MT was required by 26.3% of the patients. There was a statistically significant association between low PP and sex, length of stay, repeat extended focused assessment with sonography in trauma (eFAST), emergency operational intervention, outcome, MT, number of crystalloids consumed within the first four hours after presentation, injury severity score, systolic blood pressure (SBP), and pulse rate.

CONCLUSION

The PP <30 mmHg was observed as a useful predictor for increased blood loss requiring blood transfusion or operative intervention.

The association between lactate to albumin ratio and outcomes at early phase in patients with traumatic brain injury

BACKGROUND

The majority of traumatic brain injury (TBI) cases result in death in the early phase; predicting short-term progno-sis of affected patients is necessary to prevent this. This study aimed to examine the association between the lactate-to-albumin ratio (LAR) on admission and outcomes in the early phase of TBI.

METHODS

This retrospective observational study included patients with TBI who visited our emergency department between January 2018 and December 2020. TBI was considered as an head abbreviated injury scale (AIS) score of 3 or higher and other AIS of 2 or lower. The primary and secondary outcomes were 24-h mortality and massive transfusion (MT), respectively.

RESULTS

In total, 460 patients were included. The 24-h mortality was 12.6% (n=28) and MT was performed in 31 (6.7%) patients. In the multivariable analysis, LAR was associated with 24-h mortality (odds ratio [OR], 2.021; 95% confidence interval [CI], 1.301-3.139) and MT (OR, 1.898; 95% CI, 1.288-2.797). The areas under the curve of LAR for 24-h mortality and MT were 0.805 (95% CI, 0.766-0.841) and 0.735 (95% CI, 0.693-0.775), respectively.

CONCLUSION

LAR was associated with early-phase outcomes in patients with TBI, including 24-h mortality and MT. LAR may help predict these outcomes within 24 h in patients with TBI.

Use of recombinant human factor VIIa in 2 patients with postoperative noncompressible, abdominal hemorrhage

OBJECTIVE

To describe the clinical presentation, clinical course, and successful management of noncompressible, abdominal hemorrhage with recombinant human factor VIIa (rFVIIa) in 2 postoperative patients.

CASE SUMMARY

A 14-year-old neutered female Border Terrier and a 9-year-old neutered male domestic shorthair were treated with rFVIIa to treat noncompressible abdominal hemorrhage in the postoperative period. The dog presented for a septic abdomen following endoscopic intestinal biopsies 10 days prior and was found to have a jejunal perforation along with a fractured liver lobe and hepatic lymphoma at the time of exploratory laparotomy. The cat presented for a spontaneous hemoabdomen associated with hepatic amyloidosis. Clinically significant hemorrhage occurred in the perioperative and postoperative period and both patients received massive transfusions and antifibrinolytic therapy. Despite these interventions, the patients continued to have ongoing abdominal hemorrhage and surgical attempts at hemostasis were not attempted due to the friable nature of the liver at the time of surgery. Both patients received rFVIIa intravenously every 3 hours at a dose between 70 and 90 μg/kg as indicated by the clinical picture, which subsequently decreased transfusion requirements.

NEW OR UNIQUE INFORMATION PROVIDED

This case report describes the use of rFVIIa in a cat and a dog with severe, noncompressible abdominal hemorrhage in combination with standard hemostatic interventions.

Emergency transfusion with whole blood versus packed red blood cells: A study of 1400 patients

BACKGROUND

Low-titer group O whole blood (LTOWB) is increasingly used for emergency transfusion. We studied whether initial release of LTOWB compared with packed red blood cells (pRBCs) reduced overall blood requirements for patients needing emergency transfusion. Secondary outcomes examined included survival and non-lethal adverse clinical outcomes.

STUDY DESIGN AND METHODS

A retrospective, single-center, before-versus-after study compared patients transfused with emergency-release, uncrossmatched pRBC followed by component therapy (2016-2019) versus patients transfused with emergency-release, uncrossmatched LTOWB followed by component therapy (2019-2022).

RESULTS

Outcomes were available for 602 patients in the pRBC group versus 749 in the whole blood group. The two groups were similar for age, sex, race, estimated blood volume, ABO blood groups, and underlying diagnosis. Use of LTOWB was associated with increased blood product use at 24 h (4.0 (2.0-12.0) in pRBC group versus 6.5 (4.2-12.7) in LTOWB group, p < .0001) and at 7 days (5.5 (3.0-13.0) in pRBC group versus 7.3 (4.3-14.3) in LTOWB group, p < .0001). Initial use of LTOWB was not associated with improved 24 h or 30 day survival nor lower incidence of non-lethal adverse clinical outcomes compared with pRBC.

DISCUSSION

Our study showed a statistically significant increase in total blood use and blood acquisition costs for patients receiving initial emergency transfusion with LTOWB compared with pRBC. The initial use of LTOWB offered no advantage over component therapy for 30 day survival or selected non-lethal adverse outcomes.

Massive Transfusion Thresholds Associated with Combat Casualty Mortality during Operations in Afghanistan and Iraq: Implications for Role 1 Logistical Support Chains

INTRODUCTION

Limited literature exists examining outcomes associated with alternative thresholds for massive transfusion outside of the historical definition of 10 units of packed red blood cells (PRBC) in 24 hours. This study reports the predictive accuracy of alternative thresholds for 24-hour mortality and explores implications for Role 1 care supply requirements.

METHODS

We conducted a secondary analysis of data from the Department of Defense Trauma Registry (DODTR) spanning encounters from 1 January 2007 through 17 March 2020. We included all casualties who received at least 1 unit of either PRBC or whole blood. We calculated area under the receiver operator curve (AUROC) of blood product quantity received, including both PRBC and whole blood, as a predictor for mortality within 24 hours of arrival to a military treatment facility. We identified optimal predictive thresholds per Youden's index.

RESULTS

We identified 28,950 encounters of which 2,608 (9.0%) entailed receipt of at least 1 unit of PRBC or whole blood. Most casualties sustained battle injuries (2,437, 93.4%) with explosives as the most common mechanism (1,900, 72.8%) followed by firearms (609, 23.3%). The AUROC for blood product received within 24 hours was 0.59. The optimal threshold for predicting 24-hour mortality per Youden's Index was 20 units (sensitivity of 34.9% and specificity of 78.6%). The threshold exceeding 90% sensitivity was 2 units; whereas, the threshold exceeding 90% specificity was 33 units.

CONCLUSIONS

We identified a wide range of numbers of received blood products associated with short-term mortality based upon prioritization of sensitivity or specificity. This study found only 2 units of blood product received had a 90% sensitivity for predicting 24-hour mortality, highlighting the resource mobilization challenges that confront healthcare providers during resuscitation at the Role 1.

Massive Transfusion Thresholds Associated with Combat Casualty Mortality during Operations in Afghanistan and Iraq: Implications for Role 1 Logistical Support Chains

INTRODUCTION

Limited literature exists examining outcomes associated with alternative thresholds for massive transfusion outside of the historical definition of 10 units of packed red blood cells (PRBC) in 24 hours. This study reports the predictive accuracy of alternative thresholds for 24-hour mortality and explores implications for Role 1 care supply requirements.

METHODS

We conducted a secondary analysis of data from the Department of Defense Trauma Registry (DODTR) spanning encounters from 1 January 2007 through 17 March 2020. We included all casualties who received at least 1 unit of either PRBC or whole blood. We calculated area under the receiver operator curve (AUROC) of blood product quantity received, including both PRBC and whole blood, as a predictor for mortality within 24 hours of arrival to a military treatment facility. We identified optimal predictive thresholds per Youden's index.

RESULTS

We identified 28,950 encounters of which 2,608 (9.0%) entailed receipt of at least 1 unit of PRBC or whole blood. Most casualties sustained battle injuries (2,437, 93.4%) with explosives as the most common mechanism (1,900, 72.8%) followed by firearms (609, 23.3%). The AUROC for blood product received within 24 hours was 0.59. The optimal threshold for predicting 24-hour mortality per Youden's Index was 20 units (sensitivity of 34.9% and specificity of 78.6%). The threshold exceeding 90% sensitivity was 2 units; whereas, the threshold exceeding 90% specificity was 33 units.

CONCLUSIONS

We identified a wide range of numbers of received blood products associated with short-term mortality based upon prioritization of sensitivity or specificity. This study found only 2 units of blood product received had a 90% sensitivity for predicting 24-hour mortality, highlighting the resource mobilization challenges that confront healthcare providers during resuscitation at the Role 1.

Early Hypocalcemia in Severe Trauma: An Independent Risk Factor for Coagulopathy and Massive Transfusion

The rapid identification of patients at risk for massive blood transfusion is of paramount importance as uncontrolled exsanguination may lead to death within 2 to 6 h. The aim of this study was to analyze a cohort of severe trauma patients to identify risk factors associated with massive transfusion requirements and hypocalcemia. All major trauma (ISS > 16) presented directly from the scene to the Niguarda hospital between 1 January 2015 and 31 December 2021 were analyzed. A total of 798 patients were eligible out of 1586 screened. Demographic data showed no significant difference between hypocalcemic (HC) and normocalcemic (NC) patients except for the presence of crush trauma, alcohol intake (27% vs. 15%, p < 0.01), and injury severity score (odds ratio 1.03, p = 0.03). ISS was higher in the HC group and was an independent, even if weak, predictor of hypocalcemia (odds ratio 1.03, p = 0.03). Prehospital data showed a lower mean systolic arterial pressure (SAP) and a higher heart rate (HR) in the HC group (105 vs. 127, p < 0.01; 100 vs. 92, p < 0.001, respectively), resulting in a higher shock index (SI) (1.1 vs. 0.8, p < 0.001). Only retrospective studies such as ours are available, and while hypocalcemia seems to be an independent predictor of mortality and massive transfusion, there is not enough evidence to support causation. Therefore, randomized prospective studies are suggested.

BLOOD TYPE O IS A RISK FACTOR FOR HYPERFIBRINOLYSIS AND MASSIVE TRANSFUSION AFTER SEVERE INJURY

ABSTRACT

Background: Blood type O is the most common blood type and has lower von Willebrand factor (vWF) levels (25%-35% lower than non-O blood types). von Willebrand factor is important for initiating platelet attachment and binding factor VIII. We hypothesized that patients with type O blood are at an increased risk of trauma-induced coagulopathy and bleeding post injury. Study Design: Adult trauma activations with known blood type at a level I trauma center with field systolic blood pressure < 90 mm Hg were studied retrospectively. The relationships of blood group O versus non-O to coagulation assays, massive transfusion (MT), ventilator-free days, and mortality were adjusted for confounders. Hyperfibrinolysis (HF) was defined as thromboelastogram of percent lysis in 30 min > 3%, and fibrinolysis shutdown was defined as percent lysis in 30 min < 0.9%. von Willebrand factor activity was quantified on 212 injured patients using a STAGO apparatus. Results: Overall, 268 patients met criteria. Type O patients were more likely to develop HF than non-type O blood patients (43% vs. 29%, P = 0.06) and had significantly lower vWF activity (222% vs. 249%, P = 0.01). After adjustment for New Injury Severity Score and blunt mechanism, type O had higher odds of HF (odds ratio, 1.94, 95% confidence interval, 1.09-3.47) and increased odds of MT (odds ratio, 3.02; 95% confidence interval, 1.22-7.49). Other outcomes were not significantly affected. Conclusion: Type O patients with hypotension had increased HF and MT post injury, and these were associated with lower vWF activity. These findings have implications for the monitoring of HF in patients receiving type O whole-blood transfusions post injury.

Blood Lost: A Retrospective Review of Blood Wastage from a Massive Transfusion Protocol in a Tertiary Paediatric Hospital

BACKGROUND

The paediatric massive transfusion protocol (MTP) is activated in the paediatric population for both trauma and non-trauma related indications. While it helps to improve the efficiency and efficacy of the delivery of blood products, it can also result in increased wastage. We aimed to evaluate the wastage rates from our paediatric MTP activations from 2013 to 2018.

METHOD

As part of an audit, we retrospectively reviewed the records of the paediatric patients who had MTP activations. We collected the following data: reason for MTP activation, weight of patient, number of cycles of MTP required, blood products used, blood products wasted, deviation from our institution's recommended MTP blood product ratio, and reason for wastage.

RESULT

We had 26 paediatric MTP activations within the audit period. There was an overall wastage rate of 1.5%, with wastage occurring in 3 out of 26 patients. The reason for all wastage was demise of the patient. Most patients' transfusion ratios deviated from our institution's MTP protocol.

CONCLUSION

Our wastage rates are low likely because of clear MTP activation guidelines and a flexible MTP workflow.

Calcium Chloride Requirement and Postreperfusion Rebound During Massive Transfusion in Liver Transplantation

OBJECTIVES

The administration of citrated blood products during massive transfusion requires calcium salt administration to prevent citrate toxicity and to maintain ionized calcium values. The literature does not provide adequate guidance for the amount of calcium required during massive transfusions during liver transplantation. This study was conducted to provide guidance on calcium salt replacement during a massive transfusion in liver transplant patients, with a focus on the phase of transplantation during which citrate metabolism was minimal.

DESIGN

An observational retrospective chart review.

SETTING

An academic single-institution study of hospitalized patients.

PARTICIPANTS

One hundred thirty-two patients after liver transplantation.

INTERVENTIONS

The study authors observed documented measurements of ionized calcium and observed the ratio of calcium salts to citrated bank blood products in patients undergoing liver transplantation with complete data sets. They also observed the effect of continuous venovenous hemofiltration on the distribution of ionized calcium values.

MEASUREMENTS AND MAIN RESULTS

Prereperfusion, an average of 1.09 g CaCl₂/L of citrated blood was administered to maintain ionized calcium in the normal range. Postreperfusion, less CaCl₂ was administered, and a rebound of ionized calcium occurred. Prereperfusion, continuous venovenous hemofiltration reduced the number of ionized calcium values outside of 2 standard deviations, meaning fewer values were critically low.

CONCLUSIONS

With massive transfusions up to 67 liters (approximately 13 blood volumes), 1.09 g CaCl₂/L citrated blood maintained ionized calcium in the normal range in the absence of citrate metabolism. This ratio may have value in empiric treatment when ionized calcium measurements are unavailable, and massive transfusion rates exceed metabolic capacity.

Dynamic use of fibrinogen under viscoelastic assessment results in reduced need for plasma and diminished overall transfusion requirements in severe trauma

BACKGROUND

Despite advances in trauma management, half of trauma deaths occur secondary to bleeding. Currently, hemostatic resuscitation strategies consist of empirical transfusion of blood products in a predefined fixed ratio (1:1:1) to both treat hemorrhagic shock and correct trauma-induced coagulopathy. At our hospital, the implementation of a resuscitation protocol guided by viscoelastic hemostatic assays (VHAs) with rotational thromboelastometry has resulted in a goal-directed approach. The objective of the study is twofold, first to analyze changes in transfusion practices overtime and second to identify the impact of these changes on coagulation parameters and clinical outcomes. We hypothesized that progressive VHA implementation results in a higher administration of fibrinogen concentrate (FC) and lower use of blood products transfusion, especially plasma.

METHODS

A total of 135 severe trauma patients (January 2008 to July 2019), all requiring and initial assessment for high risk of trauma-induced coagulopathy based on high-energy injury mechanism, severity of bleeding and hemodynamic instability were included. After 2011 when we first modified the transfusion protocol, a progressive change in transfusional management occurred over time. Three treatment groups were established, reflecting different stages in the evolution of our strategy: plasma (P, n = 28), plasma and FC (PF, n = 64) and only FC (F, n = 42).

RESULTS

There were no significant differences in baseline characteristics among groups. Progressive implementation of rotational thromboelastometry resulted in increased use of FC over time ( p < 0.001). Regression analysis showed that group F had a significant reduction in transfusion of packed red blood cells ( p = 0.005), plasma ( p < 0.001), and platelets ( p = 0.011). Regarding outcomes, F patients had less pneumonia ( p = 0.019) and multiorgan failure ( p < 0.001), without significant differences for other outcomes. Likewise, overall mortality was not significantly different. However, further analysis comparing specific mortality due only to massive hemorrhage in the F group versus all patients receiving plasma, it was significantly lower ( p = 0.037).

CONCLUSION

Implementing a VHA-based algorithm resulted in a plasma-free strategy with higher use of FC and a significant reduction of packed red blood cells transfused. In addition, we observed an improvement in outcomes without an increase in thrombotic complications.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Step by step transfusion timeline and its challenges in trauma: A retrospective study in a level one trauma center

BACKGROUND

Hemorrhagic shock is the leading cause of preventable early death in trauma patients. Transfusion management is guided by international guidelines promoting early and aggressive transfusion strategies. This study aimed to describe transfusion timelines in a trauma center and to identify key points to performing early and efficient transfusions.

METHODS

This is a monocentric retrospective study of 108 severe trauma patients, transfused within the first 48 h and hospitalized in an intensive care unit between January 2017 and May 2019.

RESULTS

One hundred and eight patients were transfused with 1250 labile blood products. Half of these labile blood products were transfused within 3 h of admission and consumed by 26 patients requiring massive transfusion (≥4 red blood cells [RBC] within 1 h). Among these, the median delay from patient's admission to labile blood products prescription was -11 min (-34 to -1); from admission to delivery of labile blood products was 1 min (-20 to 16); and from admission to first transfusion was 20 min (7-37) for RBC, 26 min (13-38) for plasma, and 72 min (51-103) for platelet concentrates. The anticipated prescription of labile blood products and the use of massive transfusion packs and lyophilized plasma units were associated with earlier achievement of high transfusion ratios.

CONCLUSION

This study provides detailed data on the transfusion timelines and composition, from prescription to initial transfusion. Transfusion anticipation, use of preconditioned transfusion packs including platelets, and lyophilized plasma allow rapid and high-ratio transfusion practices in severe trauma patients.

U.S. cities will not meet blood product resuscitation standards during major mass casualty incidents: Results of a THOR-AABB working party prospective analysis

BACKGROUND

Mass casualty incidents (MCIs) create an immediate surge in blood product demand. We hypothesize local inventories in major U.S. cities would not meet this demand.

STUDY DESIGN AND METHODS

A simulated blast in a large crowd estimated casualty numbers. Ideal resuscitation was defined as equal amounts of red blood cells (RBCs), plasma, platelets, and cryoprecipitate. Inventory was prospectively collected from six major U.S. cities at six time points between January and July 2019. City-wide blood inventories were classified as READY (>1 U/injured survivor), DEFICIENT (<10 U/severely injured survivor), or RISK (between READY and DEFICIENT), before and after resupply from local distribution centers (DC), and features of DEFICIENT cities were identified.

RESULTS

The simulated blast resulted in 2218 injured survivors including 95 with severe injuries. Balanced resuscitation would require between 950 and 2218 units each RBC, plasma, platelets and cryoprecipitate. Inventories in 88 hospitals/health systems and 10 DCs were assessed. Of 36 city-wide surveys, RISK inventories included RBCs (n = 16; 44%), plasma (n = 24; 67%), platelets (n = 6; 17%), and cryoprecipitate (n = 22; 61%) while DEFICIENT inventories included platelets (n = 30; 83%) and cryoprecipitate (n = 12; 33%). Resupply shifted most RBC and plasma inventories to READY, but some platelet and cryoprecipitate inventories remained at RISK (n = 24; 67% and n = 12; 33%, respectively) or even DEFICIENT (n = 11; 31% and n = 6; 17%, respectively). Cities with DEFICIENT inventories were smaller (p <.001) with fewer blood products per trauma bed (p <.001).

DISCUSSION

In this simulated blast event, blood product demand exceeded local supply in some major U.S. cities. Options for closing this gap should be explored to optimize resuscitation during MCIs.

Proteomics of Coagulopathy Following Injury Reveals Limitations of Using Laboratory Assessment to Define Trauma-Induced Coagulopathy to Predict Massive Transfusion

Objective

Trauma-induced coagulopathy (TIC) is provoked by multiple mechanisms and is perceived to be one driver of massive transfusions (MT). Single laboratory values using prothrombin time (INR) or thrombelastography (TEG) are used to clinically define this complex process. We used a proteomics approach to test whether current definitions of TIC (INR, TEG, or clinical judgement) are sufficient to capture the majority of protein changes associated with MT.

Methods

Eight level-I trauma centers contributed blood samples from patients available early after injury. TIC was defined as INR >1.5 (INR-TIC), TEG maximum amplitude <50mm (TEG-TIC), or clinical judgement (Clin-TIC) by the trauma surgeon. MT was defined as > 10 units of red blood cells in 24 hours or > 4 units RBC/hour during the first 4 hr. SomaLogic proteomic analysis of 1,305 proteins was performed. Pathways associated with proteins dysregulated in patients with each TIC definition and MT were identified.

Results

Patients (n=211) had a mean injury severity score of 24, with a MT and mortality rate of 22% and 12%, respectively. We identified 578 SOMAscan analytes dysregulated among MT patients, of which INR-TIC, TEG-TIC, and Clin-TIC patients showed dysregulation only in 25%, 3%, and 4% of these, respectively. TIC definitions jointly failed to show changes in 73% of the protein levels associated with MT, and failed to identify 26% of patients that received a massive transfusion. INR-TIC and TEG-TIC patients showed dysregulation of proteins significantly associated with complement activity. Proteins dysregulated in Clin-TIC or massive transfusion patients were not significantly associated with any pathway.

Conclusion

These data indicate there are unexplored opportunities to identify patients at risk for massive bleeding. Only a small subset of proteins that are dysregulated in patients receiving MT are statistically significantly dysregulated among patients whose TIC is defined based solely on laboratory measurements or clinical assessment.

Plasma, platelet and red blood cell transfusion ratios for life-threatening non-traumatic haemorrhage in medical and post-surgical patients: An observational study

BACKGROUND AND OBJECTIVES

Despite the broad utilization of component-based transfusion strategies that aim to reconstitute whole blood during acute traumatic haemorrhage, data for haemorrhage occurring outside of trauma and surgery are limited.

METHODS

This is an observational cohort study of adults experiencing critical non-traumatic, non-intraoperative haemorrhage during hospitalization at an academic medical centre from 2011 to 2015. The primary goal was to evaluate differences in plasma and platelet to red blood cell (RBC) transfusion ratios across patient demographic, clinical and laboratory characteristics. Secondarily, associations between transfusion ratios and clinical outcomes were assessed.

RESULTS

Seven hundred nine patients were included: 498 (70.2%) medical and 211 (29.8%) post surgical. The gastrointestinal tract (36.7%) was the most common site of bleeding. Most patients received RBCs without plasma (35.5%) or platelets (54.2%). Among those receiving plasma, 82.3% received a plasma to RBC ratio < 1:1 at 24 h. For platelets, the most common ratio was 1-2:1 (52.9%). Transfusion ratios were generally consistent across comorbid disease severity, admission type and anatomic sites of bleeding. Higher plasma utilization was observed in the emergency department, while greater platelet utilization occurred in intensive care units. Higher transfusion ratios were observed in those with greater laboratory haemostatic abnormalities prior to the haemorrhagic event. Clinical outcome differences were limited, though greater platelet utilization in the first 24 h was associated with higher mortality and fewer hospital-free days.

CONCLUSIONS

Transfusion ratios for critical non-traumatic haemorrhage were primarily related to laboratory abnormalities preceding the haemorrhagic event and practice environments. Clinical outcome differences across ratios were limited.

Variations in clot phenotype following injury: The MA-R ratio and fragile clots

INTRODUCTION

Trauma-induced coagulopathy is a continuum ranging from hypercoagulable to hypercoagulable phenotypes. In single-center studies, the maximum amplitude (MA) to r-time (R) (MA-R) ratio has identified a phenotype of injured patients with high mortality risk. The purpose of this study was to determine the relationship between MA-R and mortality using multicenter data and to investigate fibrinogen consumption in the development of this specific coagulopathy phenotype.

METHODS

Using the Pragmatic Randomized Optimal Platelet and Plasma Ratios data set, patients were divided into blunt and penetrating injury cohorts. MA was divided by R time from admission thromboelastogram to calculate MA-R. MA-R was used to assess odds of early and late mortality using multivariable models. Multivariable models were used to assess thrombogram values in both cohorts. Refinement of the MA-R cut point was performed with Youden index. Repeat multivariable analysis was performed with a binary CRITICAL and NORMAL MA-R.

RESULTS

In initial analysis, MA-R quartiles were not associated with mortality in the penetrating cohort. In the blunt cohort, there was an association between low MA-R and early and late mortality. A refined cut point of 11 was identified (CRITICAL: MA-R, ≤11; NORMAL: MA-R, >11). CRITICAL MA-R was associated with mortality in both penetrating and blunt subgroups. In further injury subgroup analysis, CRITICAL patients had significantly decreased fibrinogen levels in the blunt subgroup only. In both blunt and penetrating injury, there was no difference in time to initiation of thrombin burst (lagtime). However, both endogenous thrombin potential and peak thrombin levels were significantly lower in CRITICAL patients.

CONCLUSIONS

MA-R identifies a trauma-induced coagulopathy phenotype characterized in blunt injury by impaired thrombin generation that is associated with early and late mortality. The endotheliopathy and tissue factor release likely plays a role in the cascade of impaired thrombin burst, possible early fibrinogen consumption and the weaker clot identified by MA-R.

LEVEL OF EVIDENCE

Therapeutic/care management, level II.

Resuscitation Patterns and Massive Transfusion for the Critical Bleeding Dog-A Multicentric Retrospective Study of 69 Cases (2007-2013)

Objective: To describe resuscitation patterns of critically bleeding dogs, including those receiving massive transfusion (MT). Design: Retrospective study from three universities (2007-2013). Animals: Critically bleeding dogs, defined as dogs who received ≥ 25 ml/kg of blood products for treatment of hemorrhagic shock caused by blood loss. Measurements and Main Results: Sixty-nine dogs were included. Sources of critical bleeding were trauma (26.1%), intra/perioperative surgical period (26.1%), miscellaneous (24.6%), and spontaneous hemoabdomen (23.1%). Median (range) age was 7 years (0.5-18). Median body weight was 20 kg (2.6-57). Median pre-transfusion hematocrit, total protein, systolic blood pressure, and lactate were 25% (10-63), 4.1 g/dl (2-7.1), 80 mm Hg (20-181), and 6.4 mmol/L (1.1-18.2), respectively. Median blood product volume administered was 44 ml/kg (25-137.4). Median plasma to red blood cell ratio was 0.8 (0-4), and median non-blood product resuscitation fluid to blood product ratio was 0.5 (0-3.6). MT was given to 47.8% of dogs. Survival rate was 40.6%. The estimated odds of survival were higher by a factor of 1.8 (95% CI: 1.174, 3.094) for a dog with 1 g/dl higher total protein above reference interval and were lower by a factor of 0.6 (95% CI: 0.340, 0.915) per 100% prolongation of partial thromboplastin time above the reference interval. No predictors of MT were identified. Conclusions: Critical bleeding in dogs was associated with a wide range of resuscitation patterns and carries a guarded to poor prognosis.

Estimating the risks of prehospital transfusion of D-positive whole blood to trauma patients who are bleeding in England

Background and Objectives

D‐negative red cells are transfused to D‐negative females of childbearing potential (CBP) to prevent haemolytic disease of the foetus and newborn (HDFN). Transfusion of low‐titre group O whole blood (LTOWB) prehospital is gaining interest, to potentially improve clinical outcomes and for logistical benefits compared to standard of care. Enhanced donor selection requirements and reduced shelf‐life of LTOWB compared to red cells makes the provision of this product challenging.

Materials and Methods

A universal policy change to the use of D‐positive LTOWB across England was modelled in terms of risk of three specific harms occurring: risk of haemolytic transfusion reaction now or in the future, and the risk of HDFN in future pregnancies for all recipients or D‐negative females of CBP.

Results

The risk of any of the three harms occurring for all recipients was 1:14 × 10³ transfusions (credibility interval [CI] 56 × 10²–42 × 10³) while for females of CBP it was 1:520 transfusions (CI 250–1700). The latter was dominated by HDFN risk, which would be expected to occur once every 5.7 years (CI 2.6–22.5). We estimated that a survival benefit of ≥1% using LTOWB would result in more life‐years gained than lost if D‐positive units were transfused exclusively. These risks would be lower, if D‐positive blood were only transfused when D‐negative units are unavailable.

Conclusion

These data suggest that the risk of transfusing RhD‐positive blood is low in the prehospital setting and must be balanced against its potential benefits.

Massive transfusion and severe blood shortages: establishing and implementing predictors of futility

Massive transfusion protocols were developed to deliver blood for life-threatening haemorrhage; however, there are no guidelines to advise when massive transfusion protocols may be considered futile. Early recognition of clinical futility remains a challenge as studies have not identified variables that can accurately determine early mortality. As blood is a scarce resource, efforts to distribute it equitably to all patients who would benefit are of paramount importance. In this editorial we discuss recent data and various aspects important in developing and implementing tools that assist with determining futility in massive transfusion.

Pre-hospital critical care at major incidents

The identification, triage, and extrication of casualties followed by on-scene management and transport to an appropriate hospital after mass casualty incidents can be complicated, delivered to variable standards, and add significant delays to care. An effective pre-hospital pathway can both increase the chances of survival of individual patients and significantly influence the effectiveness of the entire emergency response.

A comparison between liquid group A plasma and thawed group A plasma for massive transfusion activation in trauma patients

BACKGROUND AND OBJECTIVES

The use of group A thawed 24-h plasma when resuscitating haemorrhagic shock patients has become more common; however, limited data exist on the clinical use of liquid plasma (LP). Our aim is to determine whether LP is of clinical benefit to patients requiring massive transfusion.

MATERIALS AND METHODS

The objective of this retrospective study was to detect any difference in 24-h survival between patients receiving liquid or thawed plasma (TP) during their massive transfusion activation. Other objectives were to report any difference in hospital length of stay (LOS), intensive care unit (ICU) LOS and in-hospital survival. Data collected included gender, age, mechanism of injury, Injury Severity Score, Revised Trauma Score and Trauma Injury Severity Score.

RESULTS

A total of 178 patients received 1283 units of LP, median 4 and range (1-56), whereas 270 patients received 2031 units of TP, median 5 and range (1-87). The two study groups were comparable in terms of gender, age, mechanism of injury, whole blood, red blood cells, platelets and cryoprecipitate transfused. The use of LP during the massive transfusion activation in traumatically injured patients was not associated with increased 24-h survival compared to when using TP, p = 0.553.

CONCLUSION

Our study did not show a difference in 24-h or 30-day survival between the use of LP compared to TP in trauma patients. LP should be considered an alternative to TP in trauma patients requiring immediate plasma resuscitation.

Staying on target: Maintaining a balanced resuscitation during damage-control resuscitation improves survival

BACKGROUND

Damage-control resuscitation (DCR) improves survival in severely bleeding patients. However, deviating from balanced transfusion ratios during a resuscitation may limit this benefit. We hypothesized that maintaining a balanced resuscitation during DCR is independently associated with improved survival.

METHODS

This was a secondary analysis of the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients receiving >3 U of packed red blood cells (PRBCs) during any 1-hour period over the first 6 hours and surviving beyond 30 minutes were included. Linear regression assessed the effect of percent time in a high-ratio range on 24-hour survival. We identified an optimal ratio and percent of time above the target ratio threshold by Youden's index. We compared patients with a 6-hour ratio above the target and above the percent time threshold (on-target) with all others (off-target). Kaplan-Meier analysis assessed the combined effect of blood product ratio and percent time over the target ratio on 24-hour and 30-day survival. Multivariable logistic regression identified factors independently associated with 24-hour and 30-day survival.

RESULTS

Of 1,245 PROMMTT patients, 524 met the inclusion criteria. Optimal targets were plasma/PRBC and platelet/PRBC of 0.75 (3:4) and ≥40% time spent over this threshold. For plasma/PRBC, on-target (n = 213) versus off-target (n = 311) patients were younger (median, 31 years; interquartile range, [22-50] vs. 40 [25-54]; p = 0.002) with similar injury burdens and presenting physiology. Similar patterns were observed for platelet/PRBC on-target (n = 116) and off-target (n = 408) patients. After adjusting for differences, on-target plasma/PRBC patients had significantly improved 24-hour (odds ratio, 2.25; 95% confidence interval, 1.20-4.23) and 30-day (odds ratio, 1.97; 95% confidence interval, 1.14-3.41) survival, while on-target platelet/PRBC patients did not.

CONCLUSION

Maintaining a high ratio of plasma/PRBC during DCR is independently associated with improved survival. Performance improvement efforts and prospective studies should capture time spent in a high-ratio range.

LEVEL OF EVIDENCE

Epidemiologic/prognostic study, level II; Therapeutic, level IV.

First-Line Administration of Fibrinogen Concentrate in the Bleeding Trauma Patient: Searching for Effective Dosages and Optimal Post-Treatment Levels Limiting Massive Transfusion-Further Results of the RETIC Study

Fibrinogen supplementation is recommended for treatment of severe trauma hemorrhage. However, required dosages and aimed for post-treatment fibrinogen levels remain a matter of discussion. Within the published RETIC study, adult patients suffering trauma-induced coagulopathy were randomly assigned to receive fibrinogen concentrate (FC) as first-line (n = 50) or crossover rescue (n = 20) therapy. Depending on bodyweight, a single dose of 3, 4, 5, or 6 g FC was administered and repeated if necessary (FibA10 < 9 mm). The dose-dependent response (changes in plasma fibrinogen and FibA10) was analyzed. Receiver operating characteristics (ROC) analysis regarding the need for massive transfusion and correlation analyses regarding fibrinogen concentrations and polymerization were performed. Median FC single doses amounted to 62.5 (57 to 66.66) mg·kg⁻¹. One FC single-dose sufficiently corrected fibrinogen and FibA10 (median fibrinogen 213 mg·dL⁻¹, median FibA10 11 mm) only in patients with baseline fibrinogen above 100 mg·dL⁻¹ and FibA10 above 5 mm, repeated dosing was required in patients with lower baseline fibrinogen/FibA10. Fibrinogen increased by 83 or 107 mg·dL⁻¹ and FibA10 by 4 or 4.5 mm after single or double dose of FC, respectively. ROC curve analysis revealed post-treatment fibrinogen levels under 204.5 mg·dL⁻¹ to predict the need for massive transfusion (AUC 0.652; specificity: 0.667; sensitivity: 0.688). Baseline fibrinogen/FibA10 levels should be considered for FC dosing as only sufficiently corrected post-treatment levels limit transfusion requirements.

Blood Products, Crystalloids, and Rapid Infusion: An Experimental Study With Magnesium

OBJECTIVES

Calcium and magnesium are concentration-dependent pro- and anticoagulant cofactors, and magnesium behaves similarly to calcium in the presence of citrate. The authors hypothesized that magnesium can cause clot formation (primary objective) when mixed with coagulation factor-containing blood products diluted with different crystalloids in a rapid- infuser reservoir. A secondary objective was the observation of any infuser alarms and stops in the event of clotting.

DESIGN

An experimental in vitro study with blood products, crystalloids, magnesium, and calcium in a rapid infuser with a reservoir using a closed-loop system.

SETTING

Anesthesia research laboratory at an urban academic tertiary medical center PARTICIPANTS: Not applicable.

INTERVENTIONS

Exposure of fresh frozen plasma (FFP) and packed red blood cells alone (control) or in combination with either normal saline (NS), lactated Ringer's solution (LR), or Plasma-Lyte A (PL) to increasing concentrations of magnesium sulphate (MgSO₄) up to 1 g. After each incremental MgSO₄ change, the authors applied a specific pump-flow sequence in a closed-loop system with a rapid-infuser reservoir, and if no clot was observed, the authors incrementally added calcium chloride (CaCl₂) up to 1 g.

MEASUREMENTS AND MAIN RESULTS

Observation of macroscopic clot and time to event, as well as occurrence and type of any pump alarms or stops. LR experiments resulted in clot observation in the reservoir by a dedicated observer after MgSO₄ 275 ± 206 mg (95% confidence interval [CI], 9-541). Adding MgSO₄ 1 g in the NS, PL, or the control experiments did not result in clot observation. Only when CaCl₂ 166.7 ± 51.64 mg (95% CI, 112.0-22.01) was added to the combination of blood products alone or mixed with NS and PL, clotting occurred. The mean FFP volume was 281 ± 48.6 mL (range, 204-340 mL) and was not different between groups (p = 0.44). Pump alarms and stops were inconsistent.

CONCLUSIONS

The addition of magnesium to a combination of LR with coagulation factor- containing blood products consistently resulted in a visible blood clot in the rapid-infuser reservoir in the authors' experimental setup. In addition to MgSO₄ 1 g in the control, NS, and PL experiments, CaCl₂ is needed before a clot can be observed.

Early packed red blood cell transfusion in major trauma patients: Evaluation and comparison of different prediction scores for massive transfusion

BACKGROUND AND OBJECTIVES

Our study sought to evaluate and compare different prediction scores for massive transfusion in-hospital packed red blood cell (PRBC) transfusions.

MATERIALS AND METHODS

Between January 2013 and December 2018, 1843 trauma patients were enrolled in the registry of a level-1 trauma centre. All prehospital and in-hospital variables needed to calculate the Shock Index and RED FLAG, Assessment of Blood Consumption (ABC) and Trauma Associated Severe Hemorrhage (TASH) scores were prospectively collected in the registry. The primary endpoint was the initiation of transfusion within the first hour of the patient's arrival at the hospital.

RESULTS

A total of 1767 patients were included for analysis with a mean age of 43 years (±19) and a mean Injury Severity Score of 15 (±14). The in-hospital TASH score had the highest predictive performance overall (area under the curve [AUC] = 0.925, 95% confidence interval [CI] [0.904-0.946]), while the RED FLAG score (AUC = 0.881, 95% CI [0.854-0.908]) had the greatest prehospital predictive performance compared to the ABC score (AUC = 0.798, 95% CI [0.759-0.837]) and Shock Index (AUC = 0.795, 95% CI [0.752-0.837]). Using their standard thresholds, the RED FLAG score was the most efficient in predicting early transfusion (sensitivity: 87%, specificity: 76%, positive predictive value: 25%, negative predictive value: 99%, Youden index: 0.63).

CONCLUSION

The RED FLAG score appears to outperform both the ABC score and the Shock Index in predicting early in-hospital transfusion in trauma patients managed by pre-hospital teams. If adopted, this score could be used to give advance warning to trauma centres or even to initiate early transfusion during pre-hospital care.

Volume of packed red blood cells and fresh frozen plasma is associated with intraoperative hypocalcaemia during large volume intraoperative transfusion

BACKGROUND

Severe hypocalcaemia is associated with increased transfusion in the trauma population. Furthermore, trauma patients developing severe hypocalcaemia have higher mortality and coagulopathy. Electrolyte abnormalities associated with massive transfusion have been less studied in the surgical population. Here, we tested the primary hypothesis that volume of packed red blood cells and fresh frozen plasma transfused intraoperatively is associated with lower nadir ionised calcium in the surgical population receiving massive resuscitation.

METHODS

We performed a retrospective observational study at an academic quaternary care centre to characterise hypocalcaemia following large volume (4 or more units packed red blood cells) intraoperative transfusion. We used multivariable linear regression to assess if volume of transfusion with packed red blood cells and fresh frozen plasma were independently associated with a lower ionised calcium. We then used multivariable logistic regressions to assess the association between ionised calcium and transfusion with: (i) mortality, (ii) acute kidney injury, and (iii) postoperative coagulopathy.

RESULTS

Hypocalcaemia following large volume resuscitation in the operating room is a very frequent occurrence (70% of cases). After controlling for demographic variables and intraoperative variables, the volume transfused intraoperative was independently associated with hypocalcaemia on multivariable linear regression. Hypocalcaemia, intraoperative transfusion of packed red blood cells, and intraoperative transfusion of fresh frozen plasma were not shown to be associated with clinical outcomes.

CONCLUSIONS

Hypocalcaemia was associated with increased transfusion volume in this single-centre study. Unlike the trauma population, hypocalcaemia was not associated with increased mortality during surgical care. Our findings suggest that despite improved practice patterns of calcium supplementation, intraoperative hypocalcaemia occurs with relatively high frequency following large volume intraoperative transfusion.

High Interleukin-6 Plasma Concentration upon Admission Is Predictive of Massive Transfusion in Severely Injured Patients

Severe bleeding remains a prominent cause of early in-hospital mortality in major trauma patients. Thus, prompt prediction of patients at risk of massive transfusion (MT) is crucial. We investigated the ability of the inflammatory marker interleukin (IL)-6 to forecast MT in severely injured trauma patients. IL-6 plasma levels were measured upon admission. Receiver operating characteristic curves (ROCs) were calculated, and sensitivity and specificity were determined. In this retrospective study, a total of 468 predominantly male (77.8%) patients, with a median injury severity score (ISS) of 25 (17–34), were included. The Youden index for the prediction of MT within 6 and 24 h was 351 pg/mL. Patients were dichotomized into two groups: (i) low-IL-6 < 350 pg/mL and (ii) high-IL-6 ≥ 350 pg/mL. IL-6 ≥ 350 pg/mL was associated with a lower prothrombin time index, a higher activated partial thromboplastin time, and a lower fibrinogen concentration compared with IL-6 < 350 pg/mL (p <0.0001 for all). Thromboelastometric parameters were significantly different between groups (p <0.03 in all). More patients in the high-IL-6 group received MT (p <0.0001). The ROCs revealed an area under the curve of 0.76 vs. 0.82 for the high-IL-6 group for receiving MT in the first 6 and 24 h. IL-6 ≥ 350 pg/mL predicted MT within 6 and 24 h with a sensitivity of 45% and 58%, respectively, and a specificity of 89%. IL-6 ≥ 350 pg/mL appears to be a reasonable early predictor for coagulopathy and MT within the first 6 and 24 h intervals. Large-scale prospective studies are warranted to confirm these findings.

Assessing predictors of futility in patients receiving massive transfusions

BACKGROUND

Massive transfusions are associated with a high mortality rate, but there is little evidence indicating when such efforts are futile. The purpose of this study was to identify clinical variables that could be used as futility indicators in massively transfused patients.

METHODS

We retrospectively analyzed 138 adult surgical patients at our institution receiving a massive transfusion (2016-2019). Peak lactate and nadir pH within 24 h of massive transfusion initiation, along with other clinical variables, were assessed as predictors of the primary outcome, in-hospital mortality.

RESULTS

The overall rate of in-hospital mortality among our patient population was 52.9% (n = 73). Increasing lactate and decreasing pH were associated with greater mortality among massively transfused patients. Mortality rates were ~2-fold higher for patients in the highest lactate category (≥10.0 mmol/L: 25 of 37; 67.6%) compared to the lowest category (0.0-4.9 mmol/L: 17 of 48; 35.4%) (p = .005), and ~2.5-fold higher for patients in the lowest pH category (<7.00: 8 of 9; 88.9%) compared to the highest category (≥7.40: 8 of 23; 34.7%) (p = .016). Increasing age was also associated with higher mortality (≥65 years: 24 of 33; 72.7%) when compared to younger patients (18-64 years: 49 of 105; 46.7%) (p = .010).

CONCLUSIONS

Peak lactate ≥10.0 mmol/L, nadir pH <7.00, and age ≥65 years were significantly associated with higher rates of in-hospital mortality among massively transfused patients. Incorporating these clinical parameters into a futility index for massive transfusions will be useful in situations where blood products are scarce and/or mortality may be unavoidable.

Transfusion-Related Acute Lung Injury During Liver Transplantation: A Scoping Review

Liver transplantation is associated with significant blood loss, often requiring massive blood product transfusion. Transfusion-related acute lung injury (TRALI) is a devastating cause of transfusion-related deaths. While reports have investigated the general incidence of TRALI, the incidence of TRALI specifically following transfusion during liver transplant remains unclear. This scoping review summarizes existing literature regarding TRALI during the liver transplantation perioperative period. Databases were searched for all articles and abstracts reporting on TRALI after liver transplantation. Data collected included number of patients studied, patient characteristics, incidences of TRALI, TRALI characteristics, and patient outcomes. The primary outcome investigated was the incidence of TRALI in the setting of liver transplantation. Thirteen full-text citations were included in this review. The incidence of TRALI post-liver transplant was 0.68% (65 of 9,554). Based on reported transfusion data, patients diagnosed with TRALI received an average of 10.92 ± 10.81 units of packed red blood cells (pRBC), 20.05 ± 15.72 units of fresh frozen plasma, and 5.75 ± 10.00 units of platelets. Common interventions following TRALI diagnosis included mechanical ventilation with positive end-expiratory pressure, inhaled high-flow oxygen, inhaled pulmonary vasodilator, and pharmacologic treatment using pressors or inotropes, corticosteroids, or diuretics. Based on reported mortality data, 26.67% of patients (12 of 45) diagnosed with TRALI died during the postoperative period. This scoping review underscores the importance of better understanding the incidence and presentation of TRALI after liver transplant surgery. The clinical implications of these results warrant the development of identification and management strategies for liver transplant patients at increased risk for developing TRALI.

Performance assessment of intravenous catheters for massive transfusion: A pragmatic in vitro study

BACKGROUND

Rapid infusion of warmed blood products is the cornerstone of trauma resuscitation and treatment of surgical and obstetric massive hemorrhage. Integral to optimizing this delivery is selection of an intravenous (IV) catheter and use of a rapid infusion device (RID). We investigated which IV catheter and RID system enabled the greatest infusion rate of blood products and the governing catheter characteristics.

STUDY DESIGN AND METHODS

The maximum flow rates of nine IV catheters were measured while infusing a mixture of packed red blood cells and fresh frozen plasma at a 1:1 ratio using a RID with and without a patient line extension. To account for IV catheters that achieved the RID's maximum 1000 ml/min, the conductance of each infusion circuit configuration was calculated.

RESULTS

IV catheters of 7-Fr caliber or higher reached the maximum pressurized flow rate. The 9-Fr multi-lumen access catheter (MAC) achieved the greatest conductance, over sevenfold greater than the 18 g peripheral catheter (4.6 vs. 0.6 ml/min/mmHg, p < .001). Conductance was positively correlated with internal radius (β = 1.098, 95% CI 4.286-5.025, p < .001) and negatively correlated with length (β= - 0.495, 95% CI -0.007 to 0.005, p < .001). Use of an extension line (β= - 0.094, 95% CI -0.505 to -0.095, p = .005) was independently associated with reduced conductance in large caliber catheters.

CONCLUSION

Short, large-diameter catheters provided the greatest infusion rates of massive transfusion blood products for the least pressure. For patients requiring the highest transfusion flow rates, extension tubing should be avoided when possible.

Pathogen reduction of whole blood: Supplementing fibrinogen partly corrects clot formation in a massive transfusion model

BACKGROUND

The use of whole blood (WB) to treat trauma patients is becoming more common. Similar to the treatment of individual components, pathogen inactivation (PI) technologies are available to treat WB. The impact of PI on WB function is not well understood. This study investigated the impact of PI of WB with riboflavin/ultraviolet (UV) light on its hemostatic function by modeling transfusion scenarios for trauma patients and assessing transfusion efficacy by rotational thromboelastometry (ROTEM). As fibrinogen is affected by PI of WB, the effect of fibrinogen supplementation commonly used in trauma patients was also analyzed in this model.

STUDY DESIGN AND METHODS

Trauma transfusion scenarios were simulated by mixing untreated WB or WB treated with the Mirasol PI technology (riboflavin/UV) in different ratios with hemodiluted blood, and the thromboelasticity was monitored by ROTEM. The impact of supplementation with the fibrinogen concentrate RiaSTAP was investigated in this model.

RESULTS

Pathogen-inactivated WB (PI-WB) showed decreased activity in the hemostatic profile compared to the untreated control. Hemodiluted blood at a hematocrit (hct) of 20%, which was reconstituted with PI-WB or untreated WB, exhibited increased alpha values, maximum clot firmness, and clot formation time. Simulating transfusion scenarios by blood replacement with PI-WB resulted in a significant difference in ROTEM parameters between reconstituted PI-treated and -untreated WB (p ≥ .05). The effect of PI treatment waned when PI-WB was enriched with fibrinogen.

CONCLUSION

ROTEM investigations suggest that PI treatment has a negative impact on WB clot formation unless fibrinogen supplementation is used.

MATRA-A: A study on massive transfusion

BACKGROUND

We use massive transfusion in various clinical conditions and it is associated with high mortality. Although some massive transfusion protocols improve patient outcomes, the clinical circumstances requiring it are not well defined.

METHODS

MATRA-A is a multicenter retrospective study. Six University and Training Research Hospitals in Ankara participated in the study. We collected clinical data on patients (>18 years) who received massive transfusions (≥10 units/24 h) from 2017 through 2019.

RESULTS

Overall, 167 (0·27% of transfused patients) received a massive transfusion of 2586 units of red blood cells (1·5% of total RBCs transfused). The median interquartile range values for RBCs, fresh frozen plasma (FFP) and platelets were 13 (11-176), 16 (9-33) and 4 (0-11), respectively. Surgical patients received 90% of massive transfusions. The most common clinical indications for massive transfusion were cardiovascular diseases (42·6%), trauma (20·3%) and malignancies (11%). FFP: RBC: Platelets ratio was 1·9:1:0·5. The overall and trauma-related mortality rates were 57·4% and 61·8%, respectively. The hospital mortality rates of trauma patients that received high vs. low ratio (FFP: RBCs > 1:1·5 vs. ≤1:1·5) transfusions were 47·6% and 86·6% and the difference was statistically significant (P = 0·03).

CONCLUSION

Cardiovascular diseases and trauma occasion are the most common causes of massive transfusion. It is infrequent in clinical settings and is associated with high mortality rates. Additionally, in massively transfused trauma patients, a high FFP:RBCs ratio seems to be associated with increased survival. Focused prospective studies are required to define the areas that need improvement on a national scale.

The risk to future pregnancies of transfusing Rh(D)-negative females of childbearing potential with Rh(D)-positive red blood cells during trauma resuscitation is dependent on their age at transfusion

BACKGROUND

A risk assessment model for predicting the risk of haemolytic disease of the fetus and newborn (HDFN) in future pregnancies following the transfusion of Rh(D)-positive red blood cell (RBC)-containing products to females of childbearing potential (FCP) was developed, accounting for the age that the FCP is transfused in various countries.

METHODS

The HDFN risk prediction model included the following inputs: risk of FCP death in trauma, Rh(D) alloimmunization rate following Rh(D)-positive RBC transfusion, expected number of live births following resuscitation, probability of carrying an Rh(D)-positive fetus, the probability of HDFN in an Rh(D)-positive fetus carried by an alloimmunized mother. The model was implemented in Microsoft R Open, and one million FCPs of each age between 18 and 49 years old were simulated. Published data from eight countries, including the United States, were utilized to generate country-specific HDFN risk estimates.

RESULTS

The risk predictions showed similar characteristics for each country in that the overall risk of having a pregnancy affected by HDFN was higher if the FCP was younger when she received her Rh(D)-positive transfusion than if she was older. In the United States, the overall risk of HDFN if the FCP was transfused at age 18 was 3·4% (mild: 1·20%, moderate: 0·45%; severe: 1·15%; IUFD: 0·57%); the risk was approximately 0% if the FCP was 43 years or older at the time of transfusion.

CONCLUSION

This model can be used to predict HDFN outcomes when establishing transfusion policies as it relates to the administration of Rh(D)-positive products for massively bleeding FCPs.

Hemostatic defects in massive transfusion: an update and treatment recommendations

INTRODUCTION

Acute hemorrhage is a global healthcare issue, and remains the leading preventable cause of death in trauma. Acute severe hemorrhage can be related to traumatic, peripartum, gastrointestinal, and procedural causes. Hemostatic defects occur early in patients requiring massive transfusion. Early recognition and treatment of hemorrhage and hemostatic defects are required to save lives and to achieve optimal patient outcomes.

AREAS COVERED

This review discusses current evidence and trials aimed at identifying the optimal treatment for hemostatic defects in hemorrhage and massive transfusion. Literature search included PubMed and Embase.

EXPERT OPINION

Patients with acute hemorrhage requiring massive transfusion commonly develop coagulopathy due to specific hemostatic defects, and accurate diagnosis and prompt correction are required for definitive hemorrhage control. Damage control resuscitation and massive transfusion protocols are optimal initial treatment strategies, followed by goal-directed individualized resuscitation using real-time coagulation monitoring. Distinct phenotypes exist in trauma-induced coagulopathy, including 'Bleeding' or 'Thrombotic' phenotypes, and hyperfibrinolysis vs. fibrinolysis shutdown. The trauma 'lethal triad' (hypothermia, coagulopathy, acidosis) has been updated to the 'lethal diamond' (including hypocalcemia). A number of controversies in optimal management exist, including whole blood vs. component therapy, use of factor concentrates vs. blood products, optimal use of tranexamic acid, and prehospital plasma and tranexamic acid administration.

Impact of Perioperative Massive Transfusion on Long Term Outcomes of Liver Transplantation: a Retrospective Cohort Study

Background: Liver transplantation (LT) is associated with a significant risk of intraoperative hemorrhage and massive blood transfusion. However, there are few relevant reports addressing the long-term impacts of massive transfusion (MT) on liver transplantation recipients. Aim: To assess the effects of MT on the short and long-term outcomes of adult liver transplantation recipients. Methods: We included adult patients who underwent liver transplantation at West China Hospital from January 2011 to February 2015. MT was defined as red blood cell (RBC) transfusion of ≥10 units within 48 hours since the application of LT. Preoperative, intraoperative and postoperative information were collected for data analyzing. We used one-to-one propensity-matching to create pairs. Kaplan-Meier survival analysis was used to compare long-term outcomes of LT recipients between the MT and non-MT groups. Univariate and multivariate logistic regression analyses were performed to evaluate the risk factors associated with MT in LT. Results: Finally, a total of 227 patients were included in our study. After propensity score matching, 59 patients were categorized into the MT and 59 patients in non-MT groups. Compared with the non-MT group, the MT group had a higher 30-day mortality (15.3% vs 0, p=0.006), and a higher incidence of postoperative complications, including postoperative pulmonary infection, abdominal hemorrhage, pleural effusion and severe acute kidney injury. Furthermore, MT group had prolonged postoperative ventilation support (42 vs 25 h, p=0.007) and prolonged durations of ICU (12.9 vs 9.5 d, p<0.001) stay. Multivariate COX regression indicated that massive transfusion (OR: 2.393, 95% CI: 1.164-4.923, p=0.018) and acute rejection (OR: 7.295, 95% CI: 2.108-25.246, p=0.02) were significant risk factors affecting long-term survivals of LT patients. The 1-year and 3-year survival rates patients in MT group were 82.5% and 67.3%, respectively, while those of non-MT group were 93.9% and 90.5%, respectively. The MT group exhibited a lower long-term survival rate than the non-MT group (HR: 2.393, 95% CI: 1.164-4.923, p<0.001). Finally, the multivariate logistic regression revealed that preoperative hemoglobin <118 g/L (OR: 5.062, 95% CI: 2.292-11.181, p<0.001) and intraoperative blood loss ≥1100 ml (OR: 3.212, 95% CI: 1.586-6.506, p = 0.001) were the independent risk factor of MT in patients undergoing LT. Conclusion: Patients receiving MT in perioperative periods of LT had worse short-term and long-term outcomes than the non-MT patients. Massive transfusion and acute rejection were significant risk factors affecting long-term survivals of LT patients, and intraoperative blood loss of over 1100 ml was the independent risk factor of MT in patients undergoing LT. The results may offer valuable information on perioperative management in LT recipients who experience high risk of MT.

Sufficient Thrombin Generation Despite 95% Hemodilution: An In Vitro Experimental Study

Guidelines for the treatment of severe bleeding comprise viscoelastic-test-guided use of coagulation factor concentrates as part of their recommendations. The aim of this study is to investigate the effects of substituting fibrinogen, prothrombin complex concentrate, and a combination of both on conventional coagulation tests, viscoelastic test results, and thrombin generation. Blood was drawn from seven healthy volunteers to obtain platelet-free plasma, which later was diluted by replacing 40%, 60%, 80%, 90%, 95%, and 99% with a crystalloid solution. The diluted samples were spiked with fibrinogen concentrate, prothrombin complex concentrate, a combination of both, or a corresponding amount of crystalloid solution. Up to a dilution level of 95%, viscoelastically determined clotting time was significantly shorter in the group substituted with fibrinogen only in comparison with the additional use of prothrombin complex concentrate. Clot firmness and endogenous thrombin potential remained at relatively stable values up to a dilution level of 95% with the substitution of fibrinogen but not prothrombin complex concentrate. Substitution of prothrombin complex concentrate led to an excessive overshoot of thrombin generation. The results of our study question currently propagated treatment algorithms for bleeding patients that include the use of prothrombin complex concentrate for patients without former intake of oral anticoagulants. Even in severely bleeding patients, thrombin generation might be sufficient to achieve adequate hemostasis.

A novel escalation from veno-venous bypass to veno-venous ECMO during orthotopic liver transplantation. A case report

We describe the challenging perioperative course of a 55-year-old patient with hepatic failure requiring liver transplantation (LT). Different modalities of the extracorporeal device were successfully used, ranging from veno-veno bypass to partial and full veno-veno extracorporeal membrane oxygenation (ECMO) in order to optimize preload, reduce bleeding from the collateral circulation, optimize acid base balance and/or improve oxygenation. The case highlights the potential use of the device as a rescue method in challenging cases. Furthermore this is the first documented case that extracorporeal CO₂ removal (ECCO₂R) is used to optimize the biochemistry profile intraoperatively during a LT. The patient was weaned off the device at the end of the case and has been discharged home.

Principles of the perioperative Patient Blood Management

The perioperative Patient Blood Management (in Hungary National Blood Donation and Blood Saving Program) is an individualized clinical practice based on a multidisciplinary consensus with a comprehensive and complex approach. It supports the rational and judicious utilization of blood products and abolishes irrational transfusion policy. Its practical implementation is based upon three pillars: 1. anemia management without transfusion, if possible; restrictive transfusion strategy; 2. minimization of blood loss; 3. enhancement of anemia tolerance. Early detection, clarification of etiology and appropriate treatment are the most important tools for the management of preoperative anemia before surgeries with a high risk of bleeding. Minimization of blood loss can be achieved by identifying patients with congenital or acquired bleeding disorders, preparing them appropriately for surgery, discontinuing anticoagulants and antiplatelet drugs for a sufficient time in the preoperative phase of surgery and reversing their effects to comply with current guidelines. Minimal-invasive approaches are preferable. Intraoperatively, atraumatic technique and accurate topical haemostasis should be provided by surgeons. Autologous blood salvage techniques and controlled hypotension in lack of contraindications can also reduce the amount of blood loss. In cases of perioperative bleeding, protocols based on international guidelines but adapted to local circumstances must be used. Ideally, it should be managed by viscoelastic test-guided, goal-directed, individualized and factor concentrate-based algorithm. Perioperatively, an ideal oxygen demand/supply ratio must be ensured to avoid oxygen debt. Restoration and maintenance of homeostasis are essential for both the effectively functioning haemostatic system and the avoidance of oxygen deficit. Implementation of the Patient Blood Management improves patient safety, reduces the cost of medical care and facilitates the national blood product supply. Its successful introduction is our common interest. Orv Hetil. 2020; 161(37): 1554-1568.

Obstetrical aspects of the National Blood Donation and Blood Saving Program

The aims of the National Blood Donation and Blood Saving Program are to support the rational and judicious utilization of blood products and abolish irrational transfusion policy to improve patient safety. In addition to the general principles, this program has got some special obstetrical aspects. Obstetrical, especially the postpartum haemorrhages belong to the leading causes of maternal mortality worldwide. In developed countries, a trend in increasing incidence can be observed. Preparing for delivery includes some important elements such as optimization of hemoglobin level, routinely applied prophylactic or therapeutic iron supplementation and early screening and comprehensive care of patients with high risk of obstetrical bleeding. The main causes of peripartum bleeding are abruptio placentae, placenta praevia, uterine atony, retained tissue in the uterus, trauma during delivery, and haemostatic disorders or their combinations. To prevent postpartum bleeding, it is important to use the active management of the third stage of labour including prophylactic utilization of uterotonics as an essential element. Utilization of blood salvage techniques with adequate indications may be considered in cases of cesarean section or postpartum haemorhage. In cases of obstetrical haemorrhage, management of surgical bleeding has the main priority by the obstetrician. Secondary coagulopathy associated with massive bleeding should be managed by viscoelastic test-guided, individualized and factor concentrate-based algorithm, however, pregnancy-specific reference and target ranges must be used that are different from the non-pregnancy values. Obstetrical bleedings belong to the potentially preventable causes of death. Hopefully, the implementation of the National Blood Donation and Blood Saving Program in the field of obstetrics can decrease the associated morbidity and mortality further. Orv Hetil. 2020; 161(37): 1588-1598.

Validation of predictive models identifying patients at risk for massive transfusion during liver transplantation and their potential impact on blood bank resource utilization

BACKGROUND

Intraoperative massive transfusion (MT) is common during liver transplantation (LT). A predictive model of MT has the potential to improve use of blood bank resources.

STUDY DESIGN AND METHODS

Development and validation cohorts were identified among deceased-donor LT recipients from 2010 to 2016. A multivariable model of MT generated from the development cohort was validated with the validation cohort and refined using both cohorts. The combined cohort also validated the previously reported McCluskey risk index (McRI). A simple modified risk index (ModRI) was then created from the combined cohort. Finally, a method to translate model predictions to a population-specific blood allocation strategy was described and demonstrated for the study population.

RESULTS

Of the 403 patients, 60 (29.6%) in the development and 51 (25.5%) in the validation cohort met the definition for MT. The ModRI, derived from variables incorporated into multivariable model, ranged from 0 to 5, where 1 point each was assigned for hemoglobin level of less than 10 g/dL, platelet count of less than 100 × 10⁹ /dL, thromboelastography R interval of more than 6 minutes, simultaneous liver and kidney transplant and retransplantation, and a ModRI of more than 2 defined recipients at risk for MT. The multivariable model, McRI, and ModRI demonstrated good discrimination (c statistic [95% CI], 0.77 [0.70-0.84]; 0.69 [0.62-0.76]; and 0.72 [0.65-0.79], respectively, after correction for optimism). For blood allocation of 6 or 15 units of red blood cells (RBCs) based on risk of MT, the ModRI would prevent unnecessary crossmatching of 300 units of RBCs/100 transplants.

CONCLUSIONS

Risk indices of MT in LT can be effective for risk stratification and reducing unnecessary blood bank resource utilization.

Massive Transfusion Protocol and Subsequent Development of Venous Thromboembolism: Statewide Analysis

BACKGROUND

Massive transfusion protocols (MTP) are a routine component of any major trauma center's armamentarium in the management of exsanguinating hemorrhages. Little is known about the potential complications of those that survive a MTP. We sought to determine the incidence of venous thromboembolism (VTE) following MTP. We hypothesized that MTP would be associated with a higher risk of VTE when compared with a risk-adjusted control population without MTP.

METHODS

The Pennsylvania Trauma Outcome Study database was retrospectively queried from 2015 to 2018 for trauma patients who developed VTE and survived until discharge at accredited trauma centers in Pennsylvania. Patient demographics, injury severity, and clinical outcomes were compared to assess differences in VTE development between MTP and non-MTP patients. A multivariate logistic regression model assessed the adjusted impact of MTP on VTE development.

RESULTS

176 010 patients survived until discharge, meeting inclusion criteria. Of those, 1667 developed a VTE (pulmonary embolism [PE]: 662 [0.4%]; deep vein thrombosis [DVT]: 1142 [0.6%]; PE and DVT: 137 [0.1%]). 1268 patients (0.7%) received MTP and, of this subset of patients, 171 (13.5%) developed a VTE during admission. In adjusted analysis, patients who had a MTP and survived until discharge had a higher odds of developing a VTE (adjusted odds ratio: 2.62; 95% CI: 2.13-3.24; P < .001).

DISCUSSION

MTP is a harbinger for higher risk of VTE in those patients who survive. This may, in part, be related to the overcorrection of coagulation deficits encountered in the hemorrhagic event. A high index of suspicion for the development of VTE as well as aggressive VTE prophylaxis is warranted in those patients who survive MTP.

Predicting the need for massive transfusion in the prehospital setting

INTRODUCTION

Massive transfusion (MT) prediction scores allowed for the early identification of patients with massive hemorrhage likely to require large volumes of blood products. Despite their utility, very few MT scoring systems have shown promise in the pre-hospital setting due to their complexity and resource limitations.

AREAS COVERED

Pub med database was utilized to identify supporting literature for this review which discusses the importance of blood-based resuscitation and highlights the utility of scoring systems to predict the need of massive transfusion. MTP scoring systems effective in the prehospital setting are specifically discussed.

EXPERT OPINION

Massive transfusions scores are useful in alerting hospitals to the severity of trauma patients and organizing resources necessary for appropriate patient care but should not completely replace clinical . The opportunity exists to extend their use to the pre-hospital setting to allow for even earlier notification and to triage patients to trauma centers best able to treat severely injured.