Rahmenbedingungen für eine intakte Hämostase

[Approaches to pre-hospital bleeding management : Current overview on civilian emergency medicine]

Severe bleeding is a typical result of traumatic injuries. Hemorrhage is responsible for almost 50% of deaths within the first 6 h after trauma. Appropriate bleeding control and coagulation therapy depends on an integrated concept of local hemostasis by primary pressure with the hands, compression, and tourniquets accompanied by prevention of hypothermia, acidosis and hypocalcemia. Additionally, permissive hypotension is accepted for suitable patients and tranexamic acid should be administered early. Multiple publications prove that prehospital transfusion of blood products (e. g. red blood cells and plasma) and coagulation factors (e. g. fibrinogen) is feasible and safe, but only required for <5% of polytrauma patients in the civilian setting.

[Hemoglobin-oriented and coagulation factor-based algorithm : Effect on transfusion needs and standardized mortality rate in massively transfused trauma patients]

BACKGROUND

Bleeding and trauma-induced coagulopathy (TIC) are major contributors to death related to trauma in the first 24 h and the major preventable contributors. Early surgical therapy and aggressive correction of TIC are key steps to prevent death in patients suffering from hemorrhage. Therefore, a standard operating procedure (SOP) using a hemoglobin (Hb)-oriented and coagulation factor-based algorithm for early correction of TIC was introduced in this level 1 trauma center. This SOP uses the correlation of the Hb values measured in the trauma bay and standard coagulation tests as the basis for various aggressive coagulation therapies.

OBJECTIVE

The aim was to investigate the effectiveness of the SOP in trauma patients requiring massive transfusions. The main objective was the effect on the transfusion requirements and the standardized mortality ratio (SMR), the ratio of observed deaths to expected/predicted deaths, in the cohort of massively transfused trauma patients after introduction of the SOP compared with a historical cohort.

METHOD

A retrospective, single center study was carried out at a supraregional trauma center between 2005 and 2014. After introduction of the Hb-oriented, coagulation factor-based SOP for correction of TIC in 2011 a before/after comparison of all trauma patients requiring massive transfusions during trauma bay resuscitation and intensive care unit (ICU) admission was carried out. Main outcome parameters were the transfusion requirement and the SMR. The historical cohort of massively transfused trauma patients before introduction of the SOP (group 1) was compared with the cohort after introduction of the SOP (group 2). Furthermore, the two cohorts were compared regarding injury severity, expected death calculated with the revised injury severity classification (RISC), hemostatic results on trauma bay and ICU admission, clotting therapy and outcome.

RESULTS

Of the 952 patients investigated 86 (9%) required massive transfusion (45 in group 1 and 41 in group 2). Both groups were comparable regarding injury severity but showed slight differences in hemostatic results on trauma bay admission, with a trend to worse results in group 2. Differences were recorded for platelet count on trauma bay admission with significantly lower values in group 2. The RISC predicted a significant difference in the mortality rate (46.5% group 1 and 65.3% group 2) but no significant differences in the observed mortality (44.4% group 1 and 47% group 2) were recorded. The SMR decreased from 0.95 in group 1 to 0.72 in group 2, meaning that in group 1 from 21 predicated trauma deaths 20 occurred and in group 2 from 27 predicated trauma deaths 19 occurred. This difference is not statistically significant (p = 0.16) due to the small sample size but is clinically relevant. A significant reduction in the requirement of red blood cell transfusions (22.8 ± 8.1 units vs 17.6 ± 7.6 units) was achieved (p = 0.003). Significant differences between the groups were observed regarding frequency and quantity of the coagulation-promoting drugs. Compared with group 1 the SOP used in group 2 achieved significantly better hemostatic results on ICU admission for fibrinogen and Quick's value and a clear trend to better results for international normalized ratio (INR) and PTT.

CONCLUSION

The SOP based on coagulation factor values and standardized clotting therapy showed a clear trend to reduction of the SMR in massively transfused trauma patients. On the other hand the SOP achieved a significant reduction in the transfusion requirements and a significant improvement in the hemostatic results in the most severely injured patients. This can be interpreted as an effective use of coagulation factors in the early hospital treatment of trauma patients with ongoing bleeding.

[Treatment of polytrauma in the intensive care unit]

The treatment of severely injured trauma patients (polytrauma) is one of the outstanding challenges in medical care. Early in the initial course the patient's diagnostics have to be scrupulously reevaluated by an interdisciplinary team (tertiary trauma survey) to reduce deleterious sequelae of missed injuries after the initial assessment. Severely injured patients stay in intensive care for an average of 11 days. During this time the patient's therapy has to ensure a high quality evidence-based intensive care treatment and simultaneously has to be tailored to the current individual injuries. Because of the fact that the damage control strategy is gaining increasing acceptance, the intensive care unit plays a pivotal role in the critical time between emergency and elective surgery. Therefore a close cooperation between physicians of the intensive care unit and all surgical disciplines involved is essential to reach the aim of therapeutic efforts. After survival of emergency treatment patients with severe trauma should be reintegrated into social and occupational life as soon as possible.

[Coagulation management in the treatment of multiple trauma]

In recent years a new understanding of trauma-associated hemorrhaging and trauma-induced coagulopathy has been achieved. This coagulopathy is multifactorial with the predominant mechanisms being tissue trauma, shock and hypoperfusion which can lead to hyperfibrinolysis by activation of the endothelium. Routinely tested coagulation parameters, such as prothrombin time and partial thromboplastin time, are frequently employed for decision making but remain problematic as they do not give any information on clot stability, lysis or platelet function. Thrombelastometry seems to be a useful alternative. A pro-active anticipatory approach is required for a successful outcome to be achieved as rescue correction is more difficult than prevention. While the pathophysiological conception of causal relationship of the mentioned therapeutic options is conclusive, an evidence-based validation by randomized controlled studies is mostly lacking. The emergency and anesthesiological concept of damage control resuscitation consists of limiting volume therapy with crystalloids and colloids to reach a mean arterial pressure > or =65 mmHg (higher for head injuries), active (re-)warming management, the prevention of a pH< or =7.2 and a base excess (BE) < or =-6 mmol/l. The early and sufficient application of hemostatic drugs is essential. Because erythrocytes play a substantial role in the coagulation process, hemoglobin (Hb) values of around 6. 2 mmol/l (10 g/dl) and/or a hematocrit of 30% should be strived for when massive non-arrested hemorrhaging occurs. After severe multiple trauma a fibrinogen deficit develops and must be adequately compensated. If coagulation therapy is carried out using fresh frozen plasma sufficient quantities (20-30 ml/kgBW) must be administered to correspondingly raise the coagulation factors. Prothrombin complex concentrates can be helpful to optimize thrombin generation during severe hemorrhaging. Because hyperfibrinolysis occurs more often than previously assumed during severe trauma, an anti-fibrinolytic therapy should be used especially for patients with an instable circulation. The platelet count should not go below 100,000/microl when hemorrhaging occurs after multiple trauma. For thrombocytopathic patients with diffuse bleeding desmopressin (DDAVP) is a therapeutic option and the "off label" use of recombinant activated factor VIIa (rFVIIa) remains an option for individual situations with stringent indications and when the above named measures to optimize the coagulation situation have been taken.

Alcohol-positive multiple trauma patients with and without blood transfusion: an outcome analysis

Background

Patients

Results

Conclusion

Hemostatic and hemorrhagic problems in neurosurgical patients

BACKGROUND

Abnormalities of the hemostasis can lead to hemorrhage, and on the other hand to thrombosis. Intracranial neoplasms, complex surgical procedures, and head injury have a specific impact on coagulation and fibrinolysis. Moreover, the number of neurosurgical patients on medication (which interferes with platelet function and/or the coagulation systems) has increased over the past years.

METHOD

The objective of this review is to recall common hemostatic disorders in neurosurgical patients on the basis of the "new concept of hemostasis". Therefore the pertinent literature was searched to provide a structured and up to date manuscript about hemostasis in Neurosurgery.

FINDINGS

According to recent scientific publications abnormalities of the coagulation system are discussed. Pathophysiological background and the rational for specific (cost)-effective perioperative hemostatic therapy is provided.

CONCLUSIONS

Perturbations of hemostasis can be multifactorial and maybe encountered in the daily practice of neurosurgery. Early diagnosis and specific treatment is the prerequisite for successful treatment and good patients outcome.