The present study evaluated in how far ABC priorities (A: airway maintenance, B: breathing/ventilation and C: circulation with hemorrhage control) with focus on the C-priority are addressed during early in-hospital care and to what extent these key issues have been controlled for prior to ICU admission in patients arriving at the ER in states of hemorrhagic shock. This analysis was based upon datasets of severely injured patients derived from the TR-DGU® database.
Patients arrived approximately 70 minutes after injury and initial pre-hospital treatment at the trauma bay. Despite improvements in the management of the severely injured at scene and a trend towards faster transportation to an appropriate medical facility, the “golden hour”, as advocated by R.A. Cowley and colleagues already in the late 1970s, was still not matched in most of the patients studied here . The “golden hour” is a widely accepted term emphasizing the relevance of time in trauma care. Liberman and co-workers have conducted a meta-analysis comparing advanced versus basic life support strategies and showed that a prolongation of pre-hospital resuscitation was associated with significantly increased mortality . However, “definitive care” for time critical issues such as ABC can be delivered under particular circumstances by highly trained pre-hospital teams within the golden hour. Therefore, the golden hour does not necessarily be missed despite pre-hospital rescue times exceeding one hour.
In the present study, a safe airway and controlled ventilation was established in 71- 78% of patients during the early pre-hospital phase of care according to the subgroups. Procedures like intubation and mechanical ventilation are associated with potential risks to the patient, for example, if not performed appropriately this may result in hypoxia including neurological consequences. Furthermore, the time factor needs to be considered which may delay transport to the appropriate hospital. Therefore, such interventions should be restricted if really needed and only to secure airway and assure ventilatory support .
The median time window in the ER for assessment and management according to ATLS and diagnostic procedures was 65 minutes. This time period included interventions such as iv-lines, chest tubes, wound management and diagnostics, for example focused assessment with sonography for trauma (FAST), x-ray, CT and cCT scaning. Huber-Wagner and colleagues emphasized whole body CT-scanning upon ER arrival as a fast and comprehensive diagnostic tool for early detection of injuries which was associated with an increased survival rate . Diagnostic procedures in the ER were interrupted in 9.3% of patients with moderate and in 15.1% of patients with severe shock due to emergency operations. The majority of severely injured patients were treated by damage control principles of surgery. Surgical procedures were addressed to life-threatening injuries expediently, while definitive surgical care was followed after stabilisation and restored physiology . Overall, the mean time interval from ER arrival until ICU admission including operative procedures was 240 minutes.
An interesting finding of the present study was that despite resuscitation efforts including damage control principles, fluid administration, circulatory and coagulation support during the early phase of in-hospital management, shock was reversed in only 1 out of 3 patients with initially moderate and in only 1 out of 4 patients with initially severe shock upon ER arrival. Thus, the majority of patients in the present study was still in the state of shock when admitted to the ICU. Although not strictly documented in the TR-DGU® these patients were frequently acidotic upon ICU arrival. Acidosis has frequently been discussed as an important trigger for coagulation dysfunction after trauma [14, 15] representing also a major component of the so-called “lethal triad” including hypothermia, acidosis and coagulpathy .
In the present study a mean of 3 litres of fluids including crystalloids and colloids were administered during ER treatment and diagnostics. Hussmann and colleagues have conducted a retrospective study of matched pairs including 1896 severely injured patients (ISS ≥ 16) with fluid administration ≤1,5 L vs. >1,5 L during the pre-hospital phase of care. Patients with fluid administration >1,5 L had a significantly higher need for blood product transfusion and a reduced ability to clot . Trauma patients with increased administration of fluids had also a significantly higher mortality (low-volume: 22.7%, high-volume: 27.6%; p < 0.01). Maegele and co-workers screened datasets of 8724 trauma patients from the TR-DGU® and showed an increase in the frequency of coagulopathy with increased amounts of fluids administered . In this study coagulopathy was present in >40% of patients with >2 L of fluids administered, in >50% with >3 L, and in >70% with >4 L fluids. The current literature and resuscitation in trauma suggests a more restrictive use of intravenous crystalloids and colloids but advocates the early use of blood products as the appropriate means of correcting hypovolemia. Vasopressors are currently not considered as a suitable approach for addressing acute hypovolemia and have been associated with increased mortality in some studies .
Another important observation from the present study was that initially disturbed coagulation function present in all patients upon ER arrival per definition could not be restored in 3 out of 4 patients prior to ICU admission. Moreover, median platelet counts had dropped to values below 100.000/μl upon ICU arrival and the percentage of patients with significant thrombocytopenia had increased from 10% to >50% during the same time interval. Previous studies have shown that disturbances in coagulation function after trauma especially in combination with hypoperfusion secondary to shock may dramatically increase mortality . Unfortunately, these drops in platelet counts could not be viewed in the context of platelet function as this information is not captured in the TR-DGU®.
In the present study, the majority of patients had received at least one pRBC between ER and ICU arrival and massive transfusion was initiated in 23% and 42% according to the subgroups with moderate and severe shock. In contrast, FFP concentrates were administered to a lesser extent and platelet concentrates were only transfused in 18% and 36% of patients, respectively, and if administered at all only at very low quantities. This is in contrast to recent evidence from the literature indicating a survival benefit if coagulation abnormalities after trauma are addressed aggressively from the very moment on as the bleeding trauma patient hits the ER door [3–5, 21–23]. Previous work from our group together with work from others has shown that mortality from trauma hemorrhage can be reduced by more balanced transfusion strategies involving pRBC and FFP transfusion in more equal ratios. Holcomb and colleagues extended this strategy by adding platelets to this approach suggesting the balanced administration of FFP: pRBC: platelets in 1:1:1 ratios . In our patient cohort presented here platelet counts dropped significantly between ER arrival and ICU admission and more than half of all patients presented with significant thrombocytopenia upon ICU admission. According to our analysis, the administration of platelet concentrates was a rarity at least in the setting assessed here. Therefore, severely injured patients even with a normal platelet count upon ER arrival seem to have a high risk to develop a thrombocytopenia and should therefore be assessed for platelet counts sequentially. Vice-versa, the use of blood products including massive transfusion has frequently been shown to be associated with risks, for example single and multi organ failure. However, the hazards of transfusion may appear somewhat trivial relative to the need of care for an exsanguinating patient.
Damage control resuscitation by using pRBC and FFP only, as advocated now by many authors, may be too time consuming to reverse global coagulation parameters into reference ranges in adequate time windows. Gonzales and colleagues reported time windows up to 14.2 hours to set back global coagulation parameters into reference ranges by using balanced ratios. Alternative approaches currently under debate suggest either the use of freezed-dried lypholized plasma or the administration of coagulation factor concentrates using an early and individualized goal directed approach to treat trauma-induced coagulopathy [24–28]. These strategies are based upon whole-blood viscoelastic testing offering a faster and more comprehensive insight into the individual coagulation in trauma including initiation, speed and quality of the clotting process [28–30]. By using this technology, it is possible to differentiate different types of coagulation dysfunction e.g. hypo-/hypercoagulable coagulopathy or hyperfibrinolysis . In response to the underlying coagulation dysfunction different but targeted therapeutic strategies have been discussed to stabilize coagulation function and reduce the need of blood products [26, 32]. The use of viscoelastic methods apart from global coagulation tests have recently been endorsed by the updated European guidelines for the management of the bleeding follow major trauma, in which Roissant and co-workers also recommend that monitoring and measures to support coagulation in the acute bleeding situation should be initiated as early as possible . The recently published S3 guideline for the management and resuscitation of severely injured patients emphasizes the central role of hemorrhage control including aggressive management of coagulation function .
The present report is limited by the number of included patients and its retrospective design. Another limitation is that the focus of data collection into the TR-DGU® is targeted to the first 48 hours after admission with data quality heavily weighted towards the time window between ER and ICU admission. Therefore, we are not able to report on blood product transfusion afterwards. Furthermore, the TR-DGU® does not offer more detailed information with regard to hemodynamics, coagulation management and ventilation as the data presented here. In addition, important triggers to further aggravate the acute coagulopathy of trauma, for example hypothermia, are likewise not documented into the TR-DGU®. Further research should be conducted with larger patient numbers and by using a prospective and more detailed approach to prove these results.