Early coagulopathy of major burns

Plasma Inclusive Resuscitation Is Not Associated With Coagulation Profile Changes in Burn Patients

INTRODUCTION

Dynamically titrated crystalloids are the standard of care for burn shock resuscitation. There are theoretical concerns that the adjunctive use of allogeneic plasma may perturb the patient's coagulation and inflammation status deleteriously. It was hypothesized that plasma-inclusive resuscitation (PIR) would not be associated with prothrombotic changes relative to baseline after thermal injury.

METHODS

Patients admitted to a regional burn center who were treated with PIR as part of their burn resuscitation were enrolled. Whole blood samples were analyzed prospectively via rapid thromboelastography and rotational thromboelastometry to assess for coagulopathy at four time points throughout their acute burn resuscitation. The mixed-effect model for repeated measures followed by Tukey's post hoc test for comparisons was used to examine group differences.

RESULTS

There were 35 patients in the analysis. Most were male (74.3%) with a median age of 43 y (32-55), concomitant inhalation injury of 28.6%, total body surface area burn size of 34% (27%-48.5%), and the overall mortality of the cohort was 28.6%. There were no transfusion reactions or thrombotic events. There were no differences in thromboelastography or rotational thromboelastometry parameters overall or when stratified by mortality, total body surface area burn, and inhalation injury. There were no significant differences between the fibrinolytic phenotypes over time.

CONCLUSIONS

Data suggest that PIR was not associated with prothrombotic or lytic changes in burn patients relative to baseline. Further research is needed to confirm these findings and evaluate efficacy of PIR in acute burn resuscitation.

Factor XIII in major burns coagulation

BACKGROUND

In the days following a burn injury, major burn patients (MBP) present a multifactorial coagulation disorder known as acute burn-induced coagulopathy. Several studies have investigated coagulation in MBPs; however, Factor XIII (FXIII), which converts fibrin monomers into a stable clot and promotes wound healing, has not yet been studied.

OBJECTIVE

To determine the kinetics of FXIII and other coagulation factors and cofactors in MBPs in order to clarify coagulopathy in these patients and its potential relationship with surgical bleeding.

METHODS

Prospective observational pilot study of the kinetics of FXIII and other coagulation factors and cofactors in MBPs during the first 30 days of burn injury.

RESULTS

FXIII levels show a significant decline of 75.10% in the interval between the burn injury and surgery, and a decline of 87.70% in the 24 h following surgery. Patients undergo surgery with a median antigenic FXIII of 32%. Plasma levels of most factors decrease significantly 24 h after the burn injury.

CONCLUSION

MBPs experience a significant decrease in plasma levels of FXIII from the time of admission up to 24 h after surgery. Abnormally low levels were observed at the time of surgery that could not be detected by other coagulation tests. The decrease in most factors at 24 h seems to be associated with dilution due to intensive fluid resuscitation.

Efficacy of tranexamic acid versus placebo in reducing blood loss during burn excisional surgery: a multi-center, double-blind, parallel, randomized placebo-controlled clinical trial (TRANEX)

BACKGROUND

Despite an increase in knowledge, blood loss during burn excisional surgery remains a major challenge and is an independent predictor of mortality. During burn surgery, limited measures are available to control the bleeding. Increased fibrinolysis could be one of the contributing factors of blood loss during burn excisional surgery. Tranexamic acid inhibits the fibrinolytic response, and a small body of evidence shows positive effects of tranexamic acid on the volume of blood loss.

METHODS

The main objectives of this study are twofold, (1) to investigate whether tranexamic acid reduces blood loss and (2) to investigate the changes in coagulation after burn trauma and during burn excisional surgery. This study is a multicenter double-blind randomized clinical trial in patients scheduled for burn excisional surgery within the Dutch burn centers. All adult patients scheduled for burn surgery with an expected blood loss of ≥ 250 are eligible for inclusion in this study. The study is powered on a blood loss reduction of 25% in the intervention group. In total, 95 subjects will be included. The intervention group will receive 1500 mg tranexamic acid versus placebo in the other group. Primary endpoint is reduction of blood loss. Secondary endpoints include occurrence of fibrinolysis during surgery, graft take of the split skin graft, and differences in coagulation and blood clot formation.

DISCUSSION

This protocol of a randomized controlled trial aims to investigate the efficacy of tranexamic acid in reducing blood loss during burn excisional surgery. Furthermore, this study aims to clarify the coagulation status after burn trauma and during the surgical process.

TRIAL REGISTRATION

EudraCT: 2020-005405-10; ClinicalTrial.gov: NCT05507983 (retrospectively registered in August 2022, inclusion started in December 2021).

An integrative literature review of factors contributing to hypothermia in adults during the emergent (ebb) phase of a severe burn injury

BACKGROUND

During the emergent (ebb) phase (first 72 h), the adult person with a severe burn experiences loss of body heat, decreased metabolism, and poor tissue perfusion putting them at risk of hypothermia, increased morbidity, and mortality. Therefore, timely and targeted care is imperative.

AIM

The aim of this integrative literature review was to develop a framework of the factors contributing to hypothermia in adults with a severe burn injury during the emergent (ebb) phase.

METHODS

An integrative review of research literature was undertaken as it provides an orderly process in the sourcing and evaluation of the literature. Only peer reviewed research articles, published in scholarly journals were selected for inclusion (n = 26). Research rigor and quality for each research article was determined using JBI Global appraisal tools relevant to the methodology of the selected study.

FINDINGS

Contributing factors were classified under three key themes: Individual, Pre-hospital, and In-hospital factors.

CONCLUSION

The structured approach enabled the development of an evidence-based framework identifying factors contributing to hypothermia in adults with a severe burn injury during the emergent (ebb) phase and adds knowledge to improve standardized care of the adult person with a severe burn injury.

Thromboembolic events in burn patients: An analysis of risk factors and different anticoagulants

BACKGROUND

Burn patients are in a state of activated coagulation, putting them at risk for thromboembolic events. Additionally, certain patient-related factors are associated with an increased risk of thrombus formation. This study aimed to evaluate the incidence of thromboembolic events and identify potential risk factors, including patient characteristics, surgical treatment, anticoagulation strategies, and laboratory parameters.

METHODS

A single-centre retrospective cohort study was conducted on all patients with burns treated between 2002 and 2020. Medical reports of patients with and without thromboembolic events were descriptively analysed. The association of time to thromboembolic events with total body surface area (TBSA) was assessed by cause-specific Cox models adjusted for different covariates. The association of time to thromboembolic events with type and dosage of anticoagulants was assessed using a cause-specific Cox proportional hazards model with time-dependent covariates, applied to a matched subset of patients.

RESULTS

The incidence of thromboembolic events was 8.1% in a cohort of 642 patients. We found a statistically significant increase in the hazard for thromboembolic events by a factor of 1.02 (95% CI 1.00 to 1.03; P ≤ 0.05) per percent increase in TBSA. We identified former alcohol abuse (HR=2.54, CI 1.33 to 4.84, P = 0.005) and higher body mass index (HR=1.06, 95% CI 1.00 to 1.12, P = 0.046) as potential risk factors for the development of thromboembolic events. We further noted inadequate median anti-Factor-X activity levels and elevated C-reactive protein and procalcitonin levels at the time of the event.

CONCLUSION

Our results showed a moderate risk of thromboembolic events among burn patients, underlining the importance of close monitoring with regard to thrombus formation. In particular, patients with higher TBSA, alcohol abuse and BMI may be evaluated more regularly for thromboembolic events. Anti-Factor-X activity levels should be determined regularly and therapy should be adjusted if necessary.

Predictors for anaemia, blood transfusion and outcome in plastic surgery patients

OBJECTIVE

In patients undergoing plastic surgery, to identify specific risk factors for anaemia and use of blood products, and assess their impact on patient outcome.

METHOD

For this retrospective study, data were analysed from patients who attended the Plastic Surgery Department at our hospital over a three-year period (2018 to 2020). Adult patients who presented with traumatic injuries, oncologic patients who underwent reconstructive procedures, and patients with soft tissue infections (STIs) who required plastic surgery for tissue coverage were included. Demographic and injury data, hospital admission characteristics, surgical procedures, laboratory test results, transfusion events, and in-hospital complications were extracted from patient records.

RESULTS

Of the 350 patients included in the study, 228 (65%) presented with trauma, 76 (22%) underwent reconstructive surgery for cancers and 46 (13%) had STIs. In total, 175 (50%) patients developed anaemia, and 37 (11%) received blood transfusions; these were 20 (54%), 5 (14%), and 12 (32%) patients in the trauma, cancer and STI groups, respectively. Associated comorbidities and upper and lower limb surgery were the most significant risk factors for anaemia, while the number of surgeries and NSTIs were identified as risk factors for blood transfusions. Direct wound closure was consistently a protective factor for both anaemia and blood transfusions. Blood transfusions were independently associated with a high risk of sepsis, wound complications, and prolonged hospital stay.

CONCLUSION

While transfusions are necessary and even lifesaving in surgical patients, blood is a finite resource and its use may negatively impact patient outcome. Therefore, ongoing research must focus on providing safe and restrictive clinical practices while developing sustainable and accessible alternatives.

The Utilisation of INR to identify coagulopathy in burn patients

Studies conflict on the significance of burn-induced coagulopathy. We posit that burn-induced coagulopathy is associated with injury severity in burns. Our purpose was to characterize coagulopathy profiles in burns and determine relationships between % total burn surface area (TBSA) burned and coagulopathy using the International Normalized Ratio (INR). Burned patients with INR values were identified in the TriNetX database and analyzed by %TBSA burned. Patients with history of transfusions, chronic hepatic failure, and those on anticoagulant medications were excluded. Interquartile ranges for INR in the burned study population were 1.2 (1.0-1.4). An INR of ≥ 1.5 was used to represent those with burn-induced coagulopathy as it fell outside the 3rd quartile. The population was stratified into subgroups using INR levels <1.5 or ≥1.5 on the day of injury. Data are average ± SD analyzed using chi-square; p < .05 was considered significant. There were 7,364 burned patients identified with INR <1.5, and 635 had INR ≥1.5. Comparing TBSA burned groups, burn-induced coagulopathy significantly increased in those with ≥20% TBSA; p = .048 at 20-29% TBSA, p = .0005 at 30-39% TBSA, and p < .0001 for 40% TBSA and above. Age played a significant factor with average age for those with burn-induced coagulopathy 59 ± 21.5 years and 46 ± 21.8 for those without (p < .0001). After matching for age, TBSA, and demographics, the risk of 28 day-mortality was higher in those with burn-induced coagulopathy compared to those without (risk difference 20.9%, p < .0001) and the odd ratio with 95% CI is 4.45 (3.399-5.825). Investigation of conditions associated with burn-induced coagulopathy showed the effect of heart diseases to be significant; 53% of patients with burn-induced coagulopathy had hypertension (p < .0001). Burn-induced coagulopathy increases with %TBSA burned. The information gained firmly reflects a link between %TBSA and burn-induced coagulopathy, which could be useful in prognosis and treatment decisions.

The use of NexoBrid™ enzymatic debridement and coagulation abnormalities

OBJECTIVES

Current evidence on how the use of bromelain-based enzymatic debridement techniques (NexoBrid™) affect patient coagulation is limited. A single patient case report [1] suggests that a patient with 15% total body surface area (TBSA) burn developed decreased coagulation activity following debridement with NexoBrid™ enzymatic debridement (ED). Regional Burns Centres in the United Kingdom may be reluctant to use ED, particularly in larger burns, citing concerns regarding coagulation. At our centre we have routinely used ED on deep partial thickness burns since 2017 including on patients with burns over 15% TBSA. This study aims to investigate whether there is a significant disruption in coagulation in patients undergoing ED with burns > 15% TBSA or admitted to intensive care compared to the standard of care (SOC) which is surgical debridement in theatre.

METHODS

This single-centre retrospective study includes all patients with a burn treated with ED at Pinderfields General Hospital Regional Burns Centre intensive care unit (ITU) from 2017 to 2020. Patients were matched to those treated with SOC at the same centre by age, % TBSA burn and presence of inhalational injury. These parameters correlate with the Baux score [9]. Percentage of burn debrided was matched as closely as possible, with coagulation profiles and platelet count taken the day before, the day of and three days following surgery.

RESULTS

Thirty-one patients were treated with ED in the intensive care unit between 2017 and 2020. Four patients were excluded due to insufficient records and one patient was anti-coagulated. Twenty-six patients were included and matched as described above. Average age of patients receiving ED was 44 years, the same in the matched group. Average TBSA burn is 35.5% (35.8% in matched group). No statistically significant difference in coagulation was seen between patients undergoing ED compared to SOC when considering prothrombin time (PT), activated partial thromboplastin time (aPTT) and platelet count. Both groups slightly breached the upper limit of normal on day 2 post ED and SOC. There was a slight breach of the lower limit of the average platelet count on day 2 post-ED which was neither statistically nor clinically significant.

CONCLUSIONS

Large burns are associated with coagulation abnormalities, therefore isolating a single variable in this cohort is challenging. However, this study found no significant change following ED use when compared to SOC and therefore no convincing evidence that ED is associated with coagulation abnormalities. This study represents one of the largest focusing on coagulation abnormalities following the use of ED, as the current literature is limited. Our study suggests that concerns regarding coagulation abnormalities should not prevent patients with large, deep partial thickness burns or full thickness burns being treated with ED.

Characteristics of blood clotting on thromboelastography in patients with early burns

BACKGROUND

Thromboelastography (TEG) is a viscoelastic test that may be used to evaluate the hemostatic function of whole blood, and it may be useful for burn patients with multiple hemostatic defects.

METHODS

We retrospectively recruited patients with burns between January 2019 and July 2021. Blood samples were drawn on admission and subjected to coagulation parameter assessment, including conventional coagulation tests and TEG assessment. Receiver operating characteristic (ROC) analysis was performed to predict the occurrence of complications in patients with early burns.

RESULTS

Ninety-three patients with early burns met the inclusion criteria. Patients with minor, moderate, severe, and extremely severe burns accounted for 19.4 %, 36.6 %, 16.1 %, and 27.9 % of all patients, respectively. Compared with the healthy controls, patients with early burns showed significant reductions in the R and K values, and significant elevation in the maximum amplitude (MA), coagulation index (CI), and alpha angle. Compared with minor and moderate burn patients, patients with severe and extremely severe burns had lower K values and thrombin time and higher alpha angle, CI, prothrombin time, international normalized ratio, D-dimer, and fibrin degradation products. Patients with hypercoagulation had lower R and K values, longer MA, longer CI, and greater alpha angle. After ROC analysis, the areas under the ROC curve for acute lung injury, acute kidney injury, and bleeding were 0.789, 0.802, and 0.900, respectively.

CONCLUSION

TEG provides insight into the hemostatic state of patients with early burns, and can predict complications in early burn patients when combined with conventional coagulation tests.

Blood transfusions in non-major burns patients

BACKGROUND

Blood transfusions are essential to treating anaemia of burn injuries. It has recently been observed that patients with non-major burns < 20%TBSA may also develop anaemia requiring transfusion of blood products. Due to the morbidity and mortality rate associated with blood transfusions better understanding of risk factors may guide clinical practices to improve patient care.

OBJECTIVE

To determine risk factors for transfusion of blood products in patients with non-major burn injuries and assess transfusion practices to establish impact on patient outcome.

METHOD

Our study included 182 adult patients with non-major burn injuries, < 20%TBSA admitted over a 3-year period at the Department of Plastic Surgery and Burns Unit of the Emergency County Hospital Cluj-Napoca. We analysed patient and injury characteristics: age, gender, %TBSA burn, %FT burn, burn site, mechanism of injury, inhalation injury, Hb lab determinations throughout admission and surgical management. Charlson comorbidities index has been determined based on cardiovascular, neurological, gastrointestinal and renal comorbidities as well as diabetes mellitus. We selected blood transfusions, wound infections and length of hospital stay as outcome for our analysis.

RESULTS

37.9% of patients included in our study developed anaemia throughout admission and 7.7% underwent blood transfusions. Mean Hb levels triggering blood transfusions have been recorded at 7.4 (IQR=8.8-9.9) g/dL. Patients who received transfusions were older, presented with higher %TBSA and associated a higher comorbidity index. They also tended to develop coagulopathy and underwent more surgical procedures to achieve wound closure. In transfused patients who associate comorbidities we observed a higher rate of wound infections and longer hospital stay.

CONCLUSIONS

Patient related comorbidities correlate with higher transfusion rates in non-major burn injuries. Due to the risk associated with the use of blood products decision to transfuse should adhere to current guideline practices and be tailored to specific patient requirements.

Coagulation side effects of enzymatic debridement in burned patients

OBJECTIVES

Bromelain-based enzymatic debridement has emerged as a valuable option to the standard surgical intervention for debridement in burn injuries. Adverse effects on coagulation parameters after enzymatic debridement have been described. The purpose of this study was to compare the effect of enzymatic and surgical debridement on coagulation.

METHODS

Between 03/2017 and 02/2021 patients with burn injuries with a total body surface area (TBSA) ≥ 1% were included in the study. Patients were categorized into two groups: the surgically debrided group and the enzymatically debrided group. Coagulation parameters were assessed daily for the first seven days of hospitalization.

RESULTS

In total 132 patients with a mean TBSA of 17% were included in this study, of which 66 received enzymatic debridement and 66 received regular surgical-debridement. Patients receiving enzymatic debridement presented significantly higher factor-V concentration values over the first seven days after admission (p = <0.01). Regarding coagulation parameters, we found no difference in INR-, aPTT-, fibrinogen-, factor-XIII- and thrombocyte-concentrations over the first seven days (p = >0.05).

CONCLUSION

Enzymatic debridement in burned patients does not appear to increase the risk of coagulation abnormalities compared with the regular surgical approach.

Tranexamic acid in burn surgery: A systematic review and meta-analysis

Burn injury causes a coagulopathy that is poorly understood. After severe burns, significant fluid losses are managed by aggressive resuscitation that can lead to hemodilution. These injuries are managed by early excision and grafting, which can cause significant bleeding and further decrease blood cell concentration. Tranexamic acid (TXA) is an anti-fibrinolytic that has been shown to reduce surgical blood losses; however, its use in burn surgery is not well established. We performed a systematic review and meta-analysis to investigate the influence TXA may have on burn surgery outcomes. Eight papers were included, with outcomes considered in a random-effects model meta-analysis. Overall, when compared to the control group, TXA significantly reduced total volume blood loss (mean difference (MD) = -192.44; 95% confidence interval (CI) = -297.73 to - 87.14; P = 0.0003), the ratio of blood loss to burn injury total body surface area (TBSA) (MD = -7.31; 95% CI = -10.77 to -3.84; P 0.0001), blood loss per unit area treated (MD = -0.59; 95% CI = -0.97 to -0.20; P = 0.003), and the number of patients receiving a transfusion intraoperatively (risk difference (RD) = -0.16; 95% CI = -0.32 to - 0.01; P = 0.04). Additionally, there were no noticeable differences in venous thromboembolism (VTE) events (RD = 0.00; 95% CI = -0.03 to 0.03; P = 0.98) and mortality (RD = 0.00; 95% CI = -0.03 to 0.04; P = 0.86). In conclusion, TXA can potentially be a pharmacologic intervention that reduces blood losses and transfusions in burn surgery without increasing the risk of VTE events or mortality.

Coagulation Alterations in Major Burn Patients: A Narrative Review

Major burn patients (MBP) can present multifactorial coagulation alterations induced by trauma and endothelial damage, fluid replacement therapy, hypothermia, hypoperfusion, acidosis, and activation of the inflammatory cascade. However, the multiple coagulation alterations that occur are still poorly defined. The aim of this review is to combine the results of the different coagulation tests currently used to study coagulation changes in these patients. The PubMed database was searched for articles reporting factor levels or coagulation tests using the keywords "Burns" and "Blood Coagulation". Of the 720 articles retrieved from the search, 20 were finally included in the review. Coagulopathy in the MBP differs from that of the trauma patient, insofar as the former present with an increase in factors VIII, IX, and vW on admission accompanied by an increase in fibrin and thrombin production. This is followed by activation of fibrinolysis and prolonged prothrombin (PT) and thromboplastin (aPTT) times in the first 24 hours, increased fibrinogen after 48 hours, and thrombocytosis between the second and third week. Viscoelastic testing shows a pattern that shifts from normal coagulation to a hypercoagulable state with no evidence of hyperfibrinolysis. Alterations in PT and aPTT together with elevated Factor VIII have been associated with mortality, while normalization of antithrombin, and protein C and S levels are associated with a good prognosis. Although standard coagulation tests initially show alterations, the MBP does not appear to be hypocoagulable, and viscoelastic testing shows a trend toward hypercoagulability over time. Coagulation disorders affect prognosis in the MBP.

Clinical significance of R-TEG in severe burn patients with coagulation dysfunction

INTRODUCTION

The aim of this study was to retrospectively analyze Thrombelastography (TEG) data of severe burn patients to provide a clinical basis for timely diagnosis and treatment of coagulation dysfunction.

METHODS

The present study comprised burn patients with full thickness TBSA ≥ 60%. The patients included in the study were admitted to the Third Affiliated Hospital of Inner Mongolia Medical University between March 2019 and March 2022 and died within 10 days. Patient demographic and clinical data, including abbreviated burn severity index (ABSI) score, full thickness and overall total surface burn area (TBSA), injury cause, International Society on Thrombosis and Hemostasis (ISTH) score, were retrieved from the electronic medical record system. TEG data (including ACT, K, α, MA and LY30), platelet count (PLT), mean platelet volume (MPV) and platelet distribution width (PDW) data were obtained from the records of included patients for analysis.

RESULTS

A total of 9 patients were enrolled. The average burn area was 90.0% TBSA and the full-thickness TBSA was 72.0%. The results showed that α, MA and PLT count values were significantly lower relative to those at obtained throughout admission period (all p < 0.05). PDW and MPV were significantly higher compared with the values at admission (all p < 0.05). ACT time was significantly longer from day 2 after severe burn compared with the ACT time at admission (all p < 0.05). LY30 value from day 3 after severe burn was significantly higher compared with the value at admission (p < 0.05). One patient was diagnosed with diffuse intravascular coagulation (DIC) on admission, whereas eight patients were diagnosed with DIC on the day of death.

CONCLUSION

Coagulation dysfunction after severe burn is mainly characterized by procoagulant disorders and hyperfibrinolysis, which can be timely detected by TEG. Coagulation after severe burn exhibits a gradual aggravation, and can lead to death of patients.

Temporal trends, predictors of blood transfusion and in-hospital outcomes among patients with severe burn injury in the United States-A national database-based analysis

BACKGROUND

Severe burn can be accompanied by life-threatening bleeding on some occasions, thus, blood transfusion is often required in these patients during their hospitalization. Therefore, we aimed to examine temporal trends, predictors, and in-hospital outcomes of blood transfusion in these patients in the United States.

METHODS

The National Inpatient Sample was used to identify severe burn patients between January 2010 and September 2017 in the United States. Trends in the utilization of blood transfusion were analyzed using the Cochran-Armitage trend test. Moreover, propensity score matching (PSM) was employed, and then in-hospital outcomes were compared between these two groups in the matched cohort. Multivariable logistic regressions were further used to validate the results of PSM.

RESULTS

Among 27,260 severe burn patients identified during the study period, 2120 patients (7.18%) received blood transfusion. Blood transfusion rates decreased significantly from 9.52% in 2010 to 5.02% in 2017 (p for trend <.001). In the propensity-matched cohort (2120 pairs with and without transfusion), patients transfused were at increased risk of in-hospital mortality (13.3% vs 8.77%, p < .001), overall postoperative complications (88.3% vs 72.59%, p < .001), longer hospital stays (defined as > median hospital stays = 5 d) (73.8% vs 50.6%, p < .001) and increased overall cost (defined as > median overall costs = 30,746) (81.6% vs 57.3%, p < .001). This was also the case for the multivariable analysis.

CONCLUSIONS

Blood transfusion following severe burn injury may be associated with worse clinical outcomes. The utility for blood transfusion in burn patients warrants further prospective exploration.

Coagulation dysfunction of severe burn patients: A potential cause of death

BACKGROUND

Research on coagulation dysfunction following burns is controversial. This study aimed to describe the coagulation changes in severe burn patients by examining coagulation parameters.

METHODS

Patients with third-degree total body surface area (TBSA) burns of ≥30% were enrolled between 2017 and 2020. Platelet (PLT) count and coagulation indexes (including APTT, INR, FIB, DD, and AT Ⅲ) were measured at admission and once weekly for 8 weeks, and statistical analysis was performed. The patient medical profiles were reviewed to extract demographic and clinical data, including TBSA, third-degree TBSA, and inhalation injury. The total intravenous fluids and transfusions of crystalloids, fresh frozen plasma (FFP), and red blood cells (RBC) were calculated during the forty-eight-hour period. The number of sepsis cases was recorded.

RESULTS

We enrolled 104 patients , and while the overall coagulation trend fluctuated, inflection points appeared around one week and demonstrated hypercoagulability. INR was significantly higher in the non-survival group than in the survivors' group from admission to three weeks after burn (all p<0.01). From post-injury week 1 to post-injury week 3, the APTT in the non-survival group was greater than in the survival group, but the non-survival group's PLT count was lower than that in the survival group (all p<0.05). At two and three weeks after burns, the FIB levels in the non-survival group were significantly lower than those of the survival group (both p<0.01). The prevalence of inhalation injury and the proportion of sepsis cases were significantly higher in the non-survival group than in the survival group ( p ＜ 0.05, p ＜ 0.001, respectively). At the time of death, APTT, INR, and FDP levels were significantly higher in the non-survival group in the survivor group, and FIB, ATIII, and PLT were significantly lower than in the survivor group (all p<0.01). On the day of death, nine of the 12 dead patients had disseminated intravascular coagulation (DIC).

CONCLUSIONS

Coagulation dysfunction was most prominent in severe burn patients 1 week after injury and presented as hypercoagulability. Large-area burn injury, large amounts of fluid resuscitation, inhalation injury, and sepsis may all contribute to coagulation dysfunction, which can further develop into DIC and even death in severe burns patients.

Coagulopathies in Intensive Care Medicine: Balancing Act between Thrombosis and Bleeding

Patient Blood Management advocates an individualized treatment approach, tailored to each patient's needs, in order to reduce unnecessary exposure to allogeneic blood products. The optimization of hemostasis and minimization of blood loss is of high importance when it comes to critical care patients, as coagulopathies are a common phenomenon among them and may significantly impact morbidity and mortality. Treating coagulopathies is complex as thrombotic and hemorrhagic conditions may coexist and the medications at hand to modulate hemostasis can be powerful. The cornerstones of coagulation management are an appropriate patient evaluation, including the individual risk of bleeding weighed against the risk of thrombosis, a proper diagnostic work-up of the coagulopathy's etiology, treatment with targeted therapies, and transfusion of blood product components when clinically indicated in a goal-directed manner. In this article, we will outline various reasons for coagulopathy in critical care patients to highlight the aspects that need special consideration. The treatment options outlined in this article include anticoagulation, anticoagulant reversal, clotting factor concentrates, antifibrinolytic agents, desmopressin, fresh frozen plasma, and platelets. This article outlines concepts with the aim of the minimization of complications associated with coagulopathies in critically ill patients. Hereditary coagulopathies will be omitted in this review.

Burn-Induced Coagulopathies: a Comprehensive Review

Burn-induced coagulopathy is not well understood, and consensus on diagnosis, prevention, and treatments are lacking. In this review, literature on burn-induced (and associated) coagulopathy is presented along with the current understanding of the effects of burn injury on the interactions among coagulation, fibrinolysis, and inflammation in the acute resuscitative phase and reconstructive phase of care. The role of conventional tests of coagulopathy and functional assays like thromboelastography or thromboelastometry will also be discussed. Finally, reported methods for the prevention and treatment of complications related to burn-induced coagulopathy will be reviewed.

Early protein C activation is reflective of burn injury severity and plays a critical role in inflammatory burden and patient outcomes

BACKGROUND

Navigating the complexities of a severe burn injury is a challenging endeavour where the natural course of some patients can be difficult to predict. Straddling both the coagulation and inflammatory cascades that feature strongly in the burns systemic pathophysiology, we propose the pleiotropic protein C (PC) system may produce a viable biomarker to assist traditional evaluation methods for diagnostic and prognostic purposes.

METHODS

We enrolled 86 patients in a prospective observational cohort study. Over three weeks, serial blood samples were taken and measured for PC, activated (A)PC, their receptor endothelial protein C receptor (EPCR), and a panel of inflammatory cytokines including C-reactive protein (CRP), tumour necrosis factor-α, interleukin (IL)-1β, IL-6, IL-8, and IL-17. Their temporal trends were analysed alongside clinical factors including burn size, burn depth, presence of inhalational injury, and a composite outcome of requiring increased support.

RESULTS

(i) APC increased from a nadir on Day 3 (2.3±2.1ng/mL vs 4.1±2.5ng/mL by Day 18, p<0.0005), only becoming appropriately correlated to PC from Day 6 onwards (r=0.412-0.721, p<0.05 for all Days 6-21). (ii) This early disturbance in the PC system was amplified in the more severe burns (≥30% total body surface area, predominantly full thickness, or with inhalational injury), which were characterised by a marked fall in PC activation (approximated by APC/PC ratio) and APC levels during Days 0-3 with low unchanged PC levels. Critically low levels of this cytoprotective agent was associated with greater inflammatory burden, as reflected by significantly elevated CRP, IL-6, and IL-8 levels in the more severe compared to less severe burns, and by negative correlations between both PC and APC with most inflammatory cytokines. (iii) Alongside clinical markers of severity at admission (burn size, burn depth, and presence of inhalational injury), only Day 0 APC/PC ratio (OR 1.048 (1.014-1.083), p=0.006), APC (OR 1.364 (1.032-1.803), p=0.029), PC (OR 0.899 (0.849-0.953), p<0.0005), and not any inflammatory cytokines were predictive markers of requiring increased support. Uniquely, decreased Day 0 PC was further individually associated with each increased total length of stay, ICU length of stay, intravenous fluid resuscitation, and total surgeries, as well as possibly mortality.

CONCLUSION

An early functional depletion of the cytoprotective PC system provides a physiological link between severe burns and the cytokine storm, likely contributing to worse outcomes. Our findings on the changes in APC, PC and PC activation during this pathological state support APC and PC as early diagnostic and prognostic biomarkers, and provides a basis for their therapeutic potential in severe burn injuries.

Treatment of Anaemia in Patients with Acute Burn Injury: A Study of Blood Transfusion Practices

Objective: To determine blood transfusion practices, risk factors, and outcomes associated with the use of blood products in the setting of the acute management of burn patients at the Victorian Adult Burn Service. Background: Patients with burn injuries have variable transfusion requirements, based on a multitude of factors. We reviewed all acute admissions to the Victorian Adult Burns Service (VABS) between 2011 and 2017: 1636 patients in total, of whom 948 had surgery and were the focus of our analysis. Method and results: Patient demographics, surgical management, transfusion details, and outcome parameters were collected and analyzed. A total of 175 patients out of the 948 who had surgery also had a blood transfusion, while 52% of transfusions occurred in the perioperative period. The median trigger haemoglobin in perioperative was 80mg/dL (IQR = 76–84.9 mg/dL), and in the non-perioperative setting was 77 mg/dL (IQR = 71.61–80.84 mg/dL). Age, gender, % total body surface area (TBSA) burn, number of surgeries, and intensive care unit and hospital length of stay were associated with transfusion. Conclusions: The use of blood transfusions is an essential component of the surgical management of major burns. As observed in our study, half of these transfusions are related to surgical procedures and may be influenced by the employment of blood conserving strategies. Furthermore, transfusion trigger levels in stable patients may be amenable to review and reduction. Risk adjusted analysis can support the implementation of blood transfusion as a useful quality indicator in burn care.

Low-soluble TREM-like transcript-1 levels early after severe burn reflect increased coagulation disorders and predict 30-day mortality

BACKGROUND

Patients with severe burns often show systemic coagulation changes in the early stage and even develop extensive coagulopathy. Previous studies have confirmed that soluble TREM-like transcript-1 (sTLT-1) mediates a novel mechanism of haemostasis and thrombosis in inflammatory vascular injury. At present, the role of sTLT-1 in patients with severe burns is not well known.

OBJECTIVE

To investigate the early association between sTLT-1 levels and markers of burn severity, coagulation disorders, endothelial permeability, shock and prognosis in patients with severe burns.

METHODS

A prospective, observational study was conducted with 60 severe burn patients (divided into a death group and a survival group according to 30-day prognosis) admitted to our hospital. Twenty-eight healthy volunteers were recruited as the control group. Blood components at 48 h after burn were analysed for sTLT-1 and biomarkers reflecting platelet activation, shock, endothelial glycocalyx damage, capillary leakage, haemostasis, fibrinolytic activity, natural anticoagulation and blood cells. We compared the three groups, analysed the correlation between sTLT-1 and biomarkers, and investigated the predictive value of sTLT-1 for 30-day prognosis.

RESULT

Compared with the surviving patients, the patients who died had a lower degree of platelet activation [lower sTLT-1, platelet factor 4 (PF-4) and platelet counts] and a higher degree of burn [higher abbreviated burn severity index score (ABSI score)], shock (higher lactate), endothelial glycocalyx damage [higher syndecan-1 and soluble thrombomodulin (sTM)] and capillary leakage [higher resuscitation fluid (0-48 h), lower albumin] as well as decreased haemostasis [higher activated partial prothrombin time (APTT), lower fibrinogen and thrombin-antithrombin III complex (TAT)], increased fibrinolytic activity [higher D-dimer and tissue-type plasminogen activator (tPA)] and decreased natural anticoagulation [lower protein C (PC) and protein S (PS)]. Higher D-dimer (P = 0.013) and lower PF-4 (P = 0.001) were significantly independently associated with lower sTLT-1. Low circulating sTLT-1 (a unit is 50 pg/mL) (odds ratio [OR] 2.08 [95% CI 1.11-3.92], P = 0.022) was an independent predictor of increased 30-day mortality.

CONCLUSION

Low sTLT-1 levels at 48 h after burn in patients with severe burns is associated with increased coagulation disorders. Low circulating sTLT-1 levels were an independent predictor of increased 30-day mortality.

Effect of acute coagulopathy before fluid administration in mortality for burned patients

BACKGROUND

The presence of acute coagulopathy and its effect on prognosis in burn patients are unclear. No studies are extant verifying early coagulopathy before fluid administration in burn patients. The current study focused on arrival coagulopathy before volume resuscitation was begun in earnest.

METHODS

Data from 137 burn patients transported directly to the hospital without fluid administration from January 2006 to December 2019 were analyzed retrospectively.

RESULTS

The non-survival group had significantly increased age, total burn surface area (TBSA) burned, various scoring systems, prothrombin time-international normalized ratio (PT-INR), activated partial thromboplastin time (APTT), the presence of coagulopathy, and lactate levels compared to the survival group. In the logistic regression analysis, the incidence of coagulopathy was independently associated with mortality. The coagulopathy group had significant increases in TBSA burned, various scoring systems, PT-INR, APTT, lactate levels, and the mortality than the noncoagulopathy group. The prognostic burn index (PBI) was significantly correlated with PT-INR and APTT. We also found a significant correlation between the serum lactate and the PT-INR, APTT, and PBI.

CONCLUSIONS

Acute coagulopathy of burn patients might be present on arrival to the hospital before fluid replacement which is an independent risk factor for in-hospital mortality.

Impact of Prehospital Hypothermia on the Outcomes of Severely Burned Patients

When treating burn injuries, to date, there still remains significant disagreement whether presence of hypothermia (HT) on burn centers' intensive care unit (BICU) admission improves or worsens outcomes. The presented single burn center experiences set out to further evaluate the incidence, cause, and potential effects of HT on outcomes in severely burned patients. Between January 2015 and February 2017, 142 severely burned patients were admitted to a BICU. Temperature at BICU admission of <36.0°C was defined as HT and ≥36.0°C as normothermia (NT). The cases were divided into two groups: HT vs NT. Fifty-four patients met inclusion criteria and were analyzed retrospectively regarding encountered complications, time of hospitalization, and overall survival. The overall incidence of HT on arrival was 62.9%. Mean duration from burn accident to BICU admission did not differ significantly, but the groups showed significant differences regarding total body surface area (TBSA; P < .05). Both groups showed a similar distribution, regarding number of surgeries, duration until first burn excision, length of ventilation, and mortality rate of patients (P > .05). However, time until death was significantly shorter in the HT group. HT at admission remains a common problem following burn injury. Main risk factors include inappropriate temperature management after injury and during transport, extent of TBSA burn, and quantity of resuscitation. Given the high incidence, the involved health care and, especially, also prehospital providers should be further educated about existing recommendations and guidelines to prevent HT.

Incidence and Prognostic Value of Acute Coagulopathy After Extensive Severe Burns

Acute burn-induced coagulopathy (ABIC) occurs after severe burns. However, the incidence, prognostic value, and clinical significance of ABIC after an extensive severe burn remain inconclusive due to wide variances in burn severity and coagulation profile evaluation timings in previous studies. This retrospective study explored the incidence and clinical and prognostic significance of early phase ABIC in 129 adult patients with extensive burns (&gt;50% total body surface area [TBSA]) admitted to the burn centers of two hospitals within 10 hours postburn injury during 2009–2017. Demographics (age and sex) and clinical data (burn severity, vital signs, prehospital fluid replacement volume, hemodynamic parameters, coagulation profile, blood gas, and blood biochemical indicators) were collected upon admission. The incidence of ABIC in patients with severe burns and its relationship with their survival and clinical significance were analyzed. The average postburn interval was 5.7 ± 2.7 hours, and the incidence of ABIC was 31% (40/129). A logistic regression analysis identified ABIC as an independent predictor of 4-week severe mortality due to severe burn. The incidence of ABIC was significantly associated with the total burn area, lactic acid levels upon admission, and postburn admission interval, but not with the prehospital fluid replacement volume. In conclusion, approximately 30% of patients with severe burns developed ABIC within 10 hours postburn, and this condition strongly predicts 4-week mortality. Although burn severity and tissue ischemia/hypoxia are main risk factors for ABIC, the pathogenesis is not fully understood and should be explored in future studies.

The effect of the acute inflammatory response of burns and its treatment on clot characteristics and quality: A prospective case controlled study

INTRODUCTION

Burns are known to have an effect on coagulation in the early period after burn. Current coagulation tests have been criticised in acute burns due to their inherent limitations. This study aims to investigate the potential for a new quantitative functional biomarker of clot quality, fractal dimension, to identify changes in clot microstructure as a result of the burn inflammatory response and its treatment.

METHODS

A total of fifty-eight burn patients were included in this prospective case-controlled study. The control group (29 patients mean TBSA 1%), and case group (29 patients mean TBSA 30%) were compared at baseline and the case group investigated further over four time points (baseline, 12h, 24h and 5-7 days). Fractal analysis was performed, as well as current markers of coagulation, inflammatory markers and point-of-care tests, Thromboelastography and Multiplate analysis.

RESULTS

Fractal dimension did not differ between groups at admission (1.73±0.06 and 1.72±0.1), and fell within the healthy index normal range (1.74±0.7), suggesting a normal clot microstructure in the early period after burn. Fractal dimension significantly reduced from baseline over the first 24h following injury (1.59±0.03 p<0.005), indicating a significant reduction in mechanical clot strength and functionality consistent with a hypocoagulable state, not identified with other markers.

CONCLUSIONS

This is the first study to quantify the changes in clot microstructure following burn injury. This study confirms clot microstructure is significantly altered during the first 24h after burn, with the production of a weaker, more porous fibrin clot, consistent with a hypocoagulable state.

The Utility of Thromboelastography to Guide Blood Product Transfusion

OBJECTIVES

To provide an overview of the clot viscoelastic testing technology and to describe its utility in guiding blood product transfusions.

METHODS

A case scenario will be discussed as well as interpretation of thromboelastography (TEG) tracings. In addition, literature examining the utility of viscoelastic testing in guiding patient management and blood product transfusions will be reviewed.

RESULTS

TEG/rotational thromboelastometry (ROTEM) is useful in evaluating clot kinetics in trauma and acutely bleeding patients. TEG/ROTEM parameters are reflective of values measured using standard coagulation assays; however, TEG/ROTEM parameters are more rapidly available and more costly. TEG and ROTEM are used in three main settings: cardiac surgery, liver transplantation, and trauma to assess global hemostasis and administration of blood products.

CONCLUSIONS

TEG/ROTEM can be helpful in guiding resuscitation and blood product transfusion. Several studies have demonstrated a reduction in transfusion of blood components with TEG/ROTEM; however, other studies have suggested that TEG/ROTEM is not clinically effective in guiding transfusion.

Natural kinetics of blood cells following major burn: Impact of early decreases in white blood cells and platelets as prognostic markers of mortality

BACKGROUND

Severely burned patients often suffer white blood cell and platelet drop following the injury. Though coagulopathy after burn injury have been reported, the association between leukopenia or thrombopenia and mortality is still unrevealed. To determine whether early drastic drops in white blood cells (WBCs) and platelets following injury can be prognostic markers in patients with major burns.

METHODS

This is a retrospective cohort study setting in a single Burn Center in Japan. Data comprising patients' characteristics and blood cell counts (red blood cells [RBCs], WBCs including neutrophils, monocytes, and lymphocytes, and platelets) over the first 30 days after burn injury were serially collected from patients suffering major burn injury (≥20% TBSA) from January 1, 2006 to December 31, 2015. To determine blood cell counts affecting 60-day mortality, we used multivariable Cox proportional hazard analysis to assess associations between each blood cell count and mortality, adjusting for age and %TBSA as covariates, and evaluated predicted value of the hazard ratio (HR) of death.

RESULTS

We enrolled 280 patients. Following burn injury, all blood cell counts were high at admission, then decreased. RBCs diminished progressively and plateaued 2 weeks after injury. WBCs decreased suddenly 2 days after injury, then increased and stabilized. Platelets decreased more rapidly than WBCs to their nadir at 3 days, then continually increased. After covariate adjustment, low RBCs from day 1 (HR: 0.566, 95% C.I. 0.423, 0.759) to day 5 (HR: 0.524, 95% C.I. 0.175, 0.576) were predictors of mortality. Neutrophil count was not a risk factor, but day 3 lymphocyte count (HR: 0.131, 95% C.I. 0.026, 0.646) and day 10 monocyte count (HR: 0.044, 95% C.I. 0.005, 0.396) were risk factors. Low platelet counts from day 3 (HR: 0.545, 95% C.I. 0.300, 0.981) to day 30 following injury were always a predictor of mortality.

CONCLUSIONS

Early thrombopenia and lymphopenia were independent risk factors for 60-day mortality, and prolonged thrombopenia and monocytopenia were independent risk factors for mortality. These findings might shed light on mechanisms of immune response following severe burns.

Burn injury and blood transfusion

PURPOSE OF REVIEW

Blood transfusion is ubiquitous in major burn injury. The present article describes recent research findings directly impacting blood transfusion strategies in major burn injury both in the operating room and the ICU.

RECENT FINDINGS

Transfusion strategies have been the focus of recent burn investigations. First, a randomized prospective trial encompassing both the ICU and operating room reported that a restrictive red blood cell transfusion threshold (7 g/dl) had equivalent outcomes to a traditional threshold (10 g/dl) for burns more than 20% in terms of mortality, infection, length of stay, duration of mechanical ventilation, and wound healing despite receiving significantly fewer transfusions. The second burn transfusion advance addresses coagulation. Although burn patients initially have elevated fibrinogen, thrombocytopenia and other coagulation disorders develop during excision. Blood product repletion should be based on measurements such as thromboelastography in addition to traditional tests. Finally, a recent randomized trial suggests that fresh-frozen plasma and platelets during burn excision more than 20% may decrease transfusion requirements.

SUMMARY

A restrictive transfusion practice during burn excision and grafting is well tolerated and effective in reducing the number of transfusions without increasing complications. Repletion of coagulation products should focus on measured deficits of platelets, fibrinogen, and factors.

Changes in ventilator settings and ventilation-induced lung injury in burn patients-A systematic review

OBJECTIVE

Ventilation strategies aiming at prevention of ventilator-induced lung injury (VILI), including low tidal volumes (V_T) and use of positive end-expiratory pressures (PEEP) are increasingly used in critically ill patients. It is uncertain whether ventilation practices changed in a similar way in burn patients. Our objective was to describe applied ventilator settings and their relation to development of VILI in burn patients.

DATA SOURCES

Systematic search of the literature in PubMed and EMBASE using MeSH, EMTREE terms and keywords referring to burn or inhalation injury and mechanical ventilation.

STUDY SELECTION

Studies reporting ventilator settings in adult or pediatric burn or inhalation injury patients receiving mechanical ventilation during the ICU stay.

DATA EXTRACTION

Two authors independently screened abstracts of identified studies for eligibility and performed data extraction.

DATA SYNTHESIS

The search identified 35 eligible studies. V_T declined from 14 ml/kg in studies performed before to around 8 ml/kg predicted body weight in studies performed after 2006. Low-PEEP levels (<10 cmH₂O) were reported in 70% of studies, with no changes over time. Peak inspiratory pressure (PIP) values above 35 cmH₂O were frequently reported. Nevertheless, 75% of the studies conducted in the last decade used limited maximum airway pressures (≤35 cmH₂O) compared to 45% of studies conducted prior to 2006. Occurrence of barotrauma, reported in 45% of the studies, ranged from 0 to 29%, and was more frequent in patients ventilated with higher compared to lower airway pressures.

CONCLUSION

This systematic review shows noticeable trends of ventilatory management in burn patients that mirrors those in critically ill non-burn patients. Variability in available ventilator data precluded us from drawing firm conclusions on the association between ventilator settings and the occurrence of VILI in burn patients.

Heller A, Sabashnikov A, Teske W. The Nomenclature, Definition and Distinction of Types of Shock

BACKGROUND

A severe mismatch between the supply and demand of oxygen is the common feature of all types of shock. We present a newly developed, clinically oriented classification of the various types of shock and their therapeutic implications.

METHODS

This review is based on pertinent publications (1990-2018) retrieved by a selective search in PubMed, and on the relevant guidelines and meta-analyses.

RESULTS

There are only four major categories of shock, each of which is mainly related to one of four organ systems. Hypovolemic shock relates to the blood and fluids compartment while distributive shock relates to the vascular system; cardiogenic shock arises from primary cardiac dysfunction; and obstructive shock arises from a blockage of the circulation. Hypovolemic shock is due to intravascular volume loss and is treated by fluid replacement with balanced crystalloids. Distributive shock, on the other hand, is a state of relative hypovolemia resulting from pathological redistribution of the absolute intravascular volume and is treated with a combination of vasoconstrictors and fluid replacement. Cardiogenic shock is due to inadequate function of the heart, which shall be treated, depending on the situation, with drugs, surgery, or other interventional procedures. In obstructive shock, hypoperfusion due to elevated resistance shall be treated with an immediate life-saving intervention.

CONCLUSION

The new classification is intended to facilitate the goal-driven treatment of shock in both the pre-hospital and the inpatient setting. A uniform treatment strategy should be established for each of the four types of shock.

Management of bleeding in major burn surgery

Major burn surgery is often associated with excessive bleeding and massive transfusion, and the development of a coagulopathy during major burn surgery is associated with increased morbidity and mortality. The aim of this study was to review the literature on intraoperative haemostatic resuscitation of burn patients during necrectomy to reveal strategies applied for haemostatic monitoring and resuscitation. We searched PubMed, EMBASE, and CENTRAL for studies published in the period 2006-2017 concerning bleeding issues related to burn surgery i.e. coagulopathy, transfusion requirements and clinical outcomes. In a broad search, a total of 1375 papers were identified. 124 of these fulfilled the inclusion criteria, and six of these were included for review. The literature confirmed that transfusion requirements increases with burn injury severity and that haemostatic monitoring by TEG^® (thrombelastography) or ROTEM^® (rotational thromboelastometry) significantly decreased intraoperative transfusions and was useful in predicting and goal-directing haemostatic therapy during excision surgery. Resuscitation of bleeding during major burn surgery in many instances was neither standardized nor haemostatic. We suggest that resuscitation should aim for normal haemostasis during the bleeding phase through close haemostatic monitoring and resuscitation. Randomised controlled trials are highly warranted to confirm the benefit of this concept.

Analysis of factor XIa, factor IXa and tissue factor activity in burn patients

INTRODUCTION

An elevated procoagulant activity observed in trauma patients is, in part, related to tissue factor (TF) located on blood cells and microparticles. However, analysis of trauma patient plasma indicates that there are other contributor(s) to the procoagulant activity. We hypothesize that factor (F)XIa and FIXa are responsible for an additional procoagulant activity in burn patients.

METHODS

Multiple time-point plasma samples from 56 burn patients (total number of samples was 471; up to 20 time-points/patient collected in 3 weeks following admission) were evaluated in a thrombin generation assay using inhibitory antibodies to TF, FIXa and FXIa.

RESULTS

Due to the limited volume of some samples, not all were analyzed for all three proteins. At admission, 10 of 53 patients (19%) had active TF, 53 of 55 (96%) had FXIa and 48 of 55 (87%) had FIXa in their plasma. 34 patients of 56 enrolled (61%) showed TF activity at one or more time-points. All patients had FXIa and 96% had FIXa at one or more time-points. Overall, TF was observed in 99 of 455 samples analyzed (22%), FXIa in 424 of 471 (90%) and FIXa in 244 of 471 (52%). The concentration of TF was relatively low and varied between 0 and 2.1pM, whereas that of FXIa was higher, exceeding 100pM in some samples. The majority of samples with FIXa had it at sub-nanomolar concentrations. No TF, FXIa and FIXa activity was detected in plasma from healthy individuals.

CONCLUSIONS

For the first time reported, the majority of plasma samples from burn patients have active FXIa and FIXa, with a significant fraction of them having active TF. The concentration of all three proteins varies in a wide range.

Measuring coagulation in burns: an evidence-based systematic review

Introduction

Dynamic monitoring of coagulation is important to predict both haemorrhagic and thrombotic complications and to guide blood product administration. Reducing blood loss and tailoring blood product administration may improve patient outcome and reduce mortality associated with transfusion. The current literature lacks a systematic, critical appraisal of current best evidence on which clinical decisions may be based.

Objectives

Establishing the role of different coagulation markers in burn patients, diagnosing coagulopathy, tailoring blood product administration and indicating prognosis.

Methods

Literature during 2004-2017 from the Cochrane Library, PubMed, Scopus, Medline and Embase was reviewed. Eligibility criteria included randomised controlled trials, systematic reviews, multi-/single-centre study and meta-analyses. Keywords searched were 'burns', 'blood coagulation disorders', 'rotem', 'blood coagulation' and 'thromboelastography'. The PRISMA flow system was used for stratification and the CASP framework for appraisal of the studies retrieved.

Results

In total, 13 articles were included after inclusion/exclusion criteria had been applied to the initial 79 studies retrieved. Hypercoagulation increases in proportion to the severity of thermal injury. Whole blood testing, using thrombelastography (TEG) and rotation thromboelastometry (ROTEM), was superior to standard plasma based tests, including prothrombin time (PT) and activated partial thromboplastin time (APTT) at detecting burn-related coagulopathies.

Conclusions

Routine laboratory markers such as PT/APTT are poor indicators of coagulation status in burns patients. Viscoelastic tests, such as TEG and ROTEM, are efficient, fast and have a potential use in the management of burn patients; however, strong evidence is lacking. This review highlights the need for more randomised controlled trials, to guide future practice.

Platelet and coagulation function before and after burn and smoke inhalation injury in sheep

BACKGROUND

Smoke inhalation and burn injury remain a major source of morbidity and mortality. There is known dysregulation of hemostasis in burn patients, but either hypercoagulation or hypocoagulation states are reported. Sheep are an established animal model for studying burn pathology and provide robust data on hemostatic function at baseline and after injury.

METHODS

After an IACUC-approved protocol, 15 sheep were anesthetized and subjected to a 40% full thickness burn with smoke inhalation. Blood was sampled at baseline, 1 day postinjury (early effects) and days 2, 3, and 4 (late effects) after injury. Assays at each timepoint assessed: hemostatic function by thromboelastography (TEG), platelet counts and function by flow cytometry and aggregometry, coagulation protein levels, and free hemoglobin. Data were analyzed by the Wilcoxon paired test (nonparametric) with significance set at less than 0.05.

RESULTS

By 24 hours postinjury, platelet counts had dropped, whereas the percent activated platelets increased. Absolute platelet functional response to the agonist adenosine diphosphate (ADP) decreased, whereas response to collagen showed no significant difference. On a per platelet basis, ADP response was unchanged, whereas the collagen response was elevated. Prothrombin time and activated partial thromboplastin time were prolonged. TEG parameters decreased significantly from baseline. Fibrinogen and factor V were trending up; coagulation proteins ATIII, factors IX and X were decreased.Late effects were followed in six animals. At day 4, platelet counts remained depressed compared with baseline with a nadir at day 2; responses to agonist on a per platelet basis remained the same for ADP and stayed elevated for collagen. Platelets continued to have elevated activation levels. Fibrinogen and factor V remained significantly elevated, whereas TEG parameters and prothrombin time, factors IX and X returned to near baseline levels.

CONCLUSION

Coagulation parameters and hemostasis are dysregulated in sheep after smoke inhalation and burn. By 24 hours, sheep were hypocoagulable and subsequently became hypercoagulable by day 4. These results suggest a three-stage coagulopathy in burn injuries with a known early consumptive hypercoagulable state which is followed by a relatively hypocoagulable state with increased bleeding risk and then a return to a relatively unknown hypercoagulability with increased susceptibility to thrombotic disorders.

Antithrombin use and 28-day in-hospital mortality among severe-burn patients: an observational nationwide study

BACKGROUND

Previous studies have suggested that antithrombin may be beneficial for treating coagulopathy in patients with severe burns. However, robust evidence for this idea is lacking. We examined the hypothesis that antithrombin may be effective in treating patients with severe burns.

METHODS

We performed propensity score-matched analyses of the nationwide administrative Japanese Diagnosis Procedure Combination inpatient database. We identified patients with severe burns (burn index ≥ 10) who were recorded in the database from 1 July 2010 to 31 March 2013. We compared patients who were administered antithrombin within 2 days of admission (antithrombin group) and those who were not administered antithrombin (control group). The main outcomes were 28-day mortality and ventilator-free days (VFDs).

RESULTS

Eligible patients (n = 3223) from 618 hospitals were categorized into either an antithrombin group (n = 152) or control group (n = 3071). Propensity score matching created a matched cohort of 103 pairs with and without antithrombin. Twenty-eight-day mortality was lower in the antithrombin group compared with the control group in propensity-matched analysis (control vs. antithrombin, 47.6 vs. 33.0%; difference, 14.6%; 95% confidence interval [CI] 1.2-28.0). Cox regression analysis showed a significant difference in 28-day in-hospital mortality between the control and antithrombin propensity-matched groups (hazard ratio 0.58; 95% CI 0.37-0.90). There were significantly more VFDs in the antithrombin compared with the control group in propensity score-matched analysis (control vs. antithrombin, 12.6 vs. 16.4 days; difference -3.7; 95% CI -7.2 to -0.12).

CONCLUSIONS

This nationwide database study demonstrated that antithrombin use may improve 28-day survival and increase VFDs in patients with severe burns. Further prospective studies are required to confirm these results.

Upon admission coagulation and platelet function in patients with thermal and electrical injuries

RATIONAL

There has been increased focus on hemostatic potential and function in the initial assessment of the patient with traumatic injuries, that not been extensively studied in patients with burns. We proposed to determine the hemostatic potential of patients with burns upon admission to the emergency department and contrasted their condition with that of healthy controls and patients with other traumatic injuries. In addition we assessed differences due to thermal versus electrical injury and evaluated the effect of burn size.

METHODS

This is a patient based prospective observational study conducted with delayed consented. Subjects at the highest level of trauma activation upon admission to the ED had a blood sample collected for research purposes and were subsequently consented. Hemostatic potential was measured by rapid thromelastography (r-TEG^®), thrombin generation by calibrated automated thrombogram (CAT) and platelet function by Multiplate^® using five activators. Burn subjects were compared to subjects with other traumatic injuries and controls. Within the burn subjects additional analysis compared mechanism (thermal vs. electrical) and burn size. Values are medians (IQR).

RESULTS

Two hundred and eighty two trauma patients (with burns n=40, 14%) and 27 controls were enrolled. Upon admission, compared to controls, subjects with burns or trauma were hyper-coagulable based on r-TEG and CAT, with increased rates of clot formation and thrombin generation. There were no differences in burns compared to other traumatic injuries. The presence of hyper-coagulation did not appear to be related to the type of burn or the percentage of total body surface area involved. Employing previous defined cut points for R-TEG driven therapeutic interventions burn patients had similar rates of hyper- and hypo-coagulation noted in patients with traumatic injuries.

CONCLUSION

Upon admission patients with burns are in a hyper-coagulable state similar to that of other trauma patients. Employing demonstrated cut points of hemostatic potential in trauma patients associated with increased risk of poor outcomes demonstrated the incidence in burn patients to be similar, suggesting that these values could be used in the early assessment of the patient with burns to guide treatment interventions.

The Use of Blood Products in Adult Patients with Burns

Introduction:

Burn anemia represents a common complication following a burn injury. Burn anemia etiology carries distinct features occurring at each stage of the post-injury and treatment periods resulting from different causes. We aimed to analyze the use of blood components in Finnish burn victims and to identify patient- and injury-related factors influencing their use.

Methods:

To study the use of blood products in burn patients, we used data collected from the Optimal Use of Blood registry, developed through co-operation between 10 major hospital districts and the Finnish Red Cross Blood Service. Burn patients ⩾18 years treated at the Helsinki University Hospital between 2005 and 2011 with an in-hospital stay ⩾1 day who received at least one transfusion during their hospital stay were included in this study.

Results:

Among all 558 burn patients, 192 (34%) received blood products during their hospital stay. The transfused cohort comprised 192 burn patients. The study cohort received a total of 6087 units of blood components, 2422 units of leukoreduced red blood cells, 1728 units of leukoreduced platelets, and 420 units of single-donor fresh frozen plasma or, after 2007, 1517 units of Octaplas® frozen plasma. All three types of blood components were administered to 29% of patients, whereas 45% received only red blood cells and 6% received only Octaplas. Transfused patients were significantly older (p < 0.001), experienced fire-/flame-related accidents and burns to multiple locations (p < 0.001), and their in-hospital mortality exceeded that for non-transfused burn patients fivefold (p < 0.05).

Discussion:

We show that Finnish adult burn patients received ample transfusions. The number of blood components transfused varied according to the anatomical location of the injury and patient survival. Whether the additional mortality is related directly to transfusions or is merely a manifestation of the more severe burn injury remains unknown.

Coagulopathy and its management in patients with severe burns

Severe burn injury is associated with systemic coagulopathy. The changes in coagulation described in patients with severe burns resemble those found patients with sepsis or major trauma. Coagulopathy in patients with severe burns is characterized by procoagulant changes, and impaired fibrinolytic and natural anticoagulation systems. Both the timing of onset and the severity of hemostatic derangements are related to the severity of the burn. The exact pathophysiology and time course of coagulopathy are uncertain, but, at least in part, result from hemodilution and hypothermia. As the occurrence of coagulopathy in patients with severe burns is associated with increased comorbidity and mortality, coagulopathy could be seen as a potential therapeutic target. Clear guidelines for the treatment of coagulopathy in patients with severe burns are lacking, but supportive measures and targeted treatments have been proposed. Supportive measures are aimed at avoiding preventable triggers such as tissue hypoperfusion caused by shock, or hemodilution and hypothermia following the usually aggressive fluid resuscitation in these patients. Suggested targeted treatments that could benefit patients with severe burns include systemic treatment with anticoagulants, but sufficient randomized controlled trial evidence is lacking.

Experimental Animal Models of Traumatic Coagulopathy: A Systematic Review

BACKGROUND

Perturbations in coagulation function are common following trauma and are associated with poor clinical outcomes. Traditionally considered an iatrogenic process, it is now recognized that an acute coagulation dysfunction develops prior to medical intervention. The mechanisms underlying the development of this acute traumatic coagulopathy remain poorly understood. Preclinical animal research is a necessary adjunct to improve mechanistic understanding and management of this condition. This review aims to identify and evaluate existing animal models of traumatic coagulopathy for clinical relevance.

METHODS

A structured search of MEDLINE/PubMed was performed in September 2014 in accordance with the PRISMA guidelines.

RESULTS

A total of 62 relevant publications describing 27 distinct models of traumatic coagulopathy were identified. Porcine models predominated, and hemodilution in isolation or in combination with hypothermia and/or acidosis was the principal mechanism for inducing coagulopathy. Acute coagulation changes in response to tissue injury and hemorrhage were evident in five publications, and pathophysiological evaluation of postulated mechanisms was performed in three studies.

CONCLUSIONS

There are few clinically relevant animal models that reflect the contemporary understanding of traumatic coagulopathy. This relative deficiency highlights the need for further development of valid and reproducible animal models of trauma. Well-designed models will facilitate improved mechanistic understanding and development of targeted treatment strategies for traumatic coagulopathy.

In-depth analysis of clotting dynamics in burn patients

BACKGROUND

Studies associating coagulopathic changes with burn injury have relied on limited tests such as partial thromboplastin time (PTT) and international normalized ratio (INR). Understanding the clotting dynamics and associated risk factors after burn injury could influence management. This work aimed to identify real-time changes in coagulation after burn injury not indicated by PTT or INR alone.

MATERIALS AND METHODS

Nine burn-injured patients at a regional burn center were enrolled for blood collection at admission and set intervals over 96 h. Patient demographics, management, and laboratory data (PTT and INR) were collected. Plasma assays determined factors II, V, VII, VIII, IX, X, XI, antithrombin, and protein C functional activity as well as PAP, D-Dimer, fibrin monomer, TFPI, IL-1b, IL-6, IL-10, IL-12p.70, and TNF-α concentrations.

RESULTS

Overall, five patients died. These patients had higher mortality scores and were more acidotic. All patients had normal coagulation studies (INR < 1.5, PTT < 45 s) within 24 h of admission, and only two were abnormal after. Increased factor VIII and IX activity were identified in seven patients at admission. Decreased antithrombin and protein C activity were seen in all patients. Patients had increased PAP, D-Dimer, and fibrin monomer concentrations throughout their hospital course. At admission, increased fold changes were seen in IL-6 (2.5-117) and IL-10 (2.4-32), whereas IL-1b and TNF-α levels were depressed in all patients.

CONCLUSIONS

Extensive changes not identified by PTT or INR were seen after burn injury that may explain perturbed coagulation in these patients. This approach further characterizes the impact thermal injury has on coagulation.

Acute blood loss during burn and soft tissue excisions: An observational study of blood product resuscitation practices and focused review

BACKGROUND

Many military and civilian centers have shifted to a damage-control resuscitation approach, focused on providing oxygen-carrying capacity while simultaneously mitigating coagulopathy with a balanced ratio of platelets and plasma to red blood cells. It is unclear to what degree this strategy is used during burn or soft tissue excision. Here, we characterized blood product transfusion during burn and soft tissue surgery and reviewed the published literature regarding intraoperative coagulation changes. We hypothesized that blood product resuscitation during burn and soft tissue excision is not hemostatic and would be insufficient to address hemorrhage-induced coagulopathy.

METHODS

Consented adult patients were enrolled into an institutional review board-approved prospective observational study. Number, component type, volume, and age of the blood products transfused were recorded during burn excision/grafting or soft tissue debridement. Component bags (packed red blood cells, fresh frozen plasma, platelets, and cryoprecipitate) were collected, and the remaining sample was harvested from the bag and tubing. Aliquots of 1/1,000th the original volume of each blood product were obtained and combined, producing an amalgam sample containing the same ratio of product transfused. Platelet count, rotational thromboelastometry, and impedance aggregometry were measured. Significance was set at p < 0.05.

RESULTS

Amalgamated transfusate samples produced abnormally weak clots (p ≤ 0.001) particularly if they did not contain platelets. Clot strength (48.8 [2.6] mm; reference range, 49-71 mm) for platelet-containing amalgams was below the lower limit of the reference range despite platelet-red blood cell ratios greater than 1:1. Platelet aggregation was abnormally low; transfused platelets were functionally inferior to native platelets.

CONCLUSION

Our study and focused review demonstrate that further work is needed to fully understand the needs of patients undergoing tissue excision. The three studies reviewed and the results of our observational work suggest that coagulopathy and thrombocytopenia may contribute to intraoperative hemorrhage. Blood product resuscitation during burn and soft tissue excision is not hemostatic.

LEVEL OF EVIDENCE

Epidemiologic study, level V.

The year in burns 2013

Approximately 3415 research articles were published with burns in the title, abstract, and/or keyword in 2013. We have continued to see an increase in this number; the following reviews articles selected from these by the Editor of one of the major journals (Burns) and colleagues that in their opinion are most likely to have effects on burn care treatment and understanding. As we have done before, articles were found and divided into the following topic areas: epidemiology of injury and burn prevention, wound and scar characterization, acute care and critical care, inhalation injury, infection, psychological considerations, pain and itching management, rehabilitation and long-term outcomes, and burn reconstruction. The articles are mentioned briefly with notes from the authors; readers are referred to the full papers for details.

Admission temperature and survival in patients admitted to burn centers

It is commonly believed that hypothermia occurring during burn resuscitation is associated with poor outcome, but there is little direct supporting evidence. The authors conducted an analysis of a statewide trauma registry to determine whether hypothermia (T ≤36.5°C) was associated with mortality when controlling for clinical confounders. They included all patients treated at an accredited burn center from 2000 to 2011 where the trauma registrar recorded the primary injury type as a burn. They excluded records with missing data and nonphysiologic temperature (<26°C or >42°C). The primary exposure of interest was hypothermia. The authors constructed a hierarchical, multivariable logistic regression model to examine the effect of hypothermia on survival, controlling for potentially confounding variables. Predictors of mortality are presented as odds ratio (95% confidence interval). Primary burn injury was coded 17,098 times during the study period. Of these, 3809 were not treated at a burn center and 1192 were excluded for missing data. Admission hypothermia was independently associated with mortality (1.91 [1.58-2.29]) when adjusting for age, sex, total second- and third-degree burn surface area (TBSA), comorbid conditions, injury severity score, direct transport vs referral, method of temperature measurement, year, and the hospital providing care. Increasing age, female sex, TBSA >40%, presence of multiple comorbid conditions, and increasing injury severity score were associated with mortality. Other variables in the model were not independently associated with outcome. There was a weak correlation between TBSA and admission temperature (r = .18). Hypothermia at hospital admission is independently associated with mortality in burn patients when controlling for clinical confounders. Future studies should address potential causes underlying this observation.

HEPBURN - investigating the efficacy and safety of nebulized heparin versus placebo in burn patients with inhalation trauma: study protocol for a multi-center randomized controlled trial

BACKGROUND

Pulmonary coagulopathy is a hallmark of lung injury following inhalation trauma. Locally applied heparin attenuates lung injury in animal models of smoke inhalation. Whether local treatment with heparin benefits patients with inhalation trauma is uncertain. The present trial aims at comparing a strategy using frequent nebulizations of heparin with standard care in intubated and ventilated burn patients with bronchoscopically confirmed inhalation trauma.

METHODS

The Randomized Controlled Trial Investigating the Efficacy and Safety of Nebulized HEParin versus Placebo in BURN Patients with Inhalation Trauma (HEPBURN) is an international multi-center, double-blind, placebo-controlled, two-arm study. One hundred and sixteen intubated and ventilated burn patients with confirmed inhalation trauma are randomized to nebulizations of heparin (the nebulized heparin strategy) or nebulizations of normal saline (the control strategy) every four hours for 14 days or until extubation, whichever comes first. The primary endpoint is the number of ventilator-free days, defined as days alive and breathing without assistance during the first 28 days, if the period of unassisted breathing lasts for at least 24 consecutive hours.

DISCUSSION

As far as the authors know, HEPBURN is the first randomized, placebo-controlled trial, powered to investigate whether local treatment with heparin shortens duration of ventilation of intubated and ventilated burn patients with inhalation trauma.

TRIAL REGISTRATION

NCT01773083 (http://www.clinicaltrials.gov), registered on 16 January 2013.Recruiting. Randomisation commenced on 1 January 2014.