[The chapters "Stop the bleed-prehospital" and "Coagulation management and volume therapy (emergency departement)" in the new S3 guideline "Polytrauma/severe injury treatment"]

The S3 guideline on the treatment of patients with severe/multiple injuries by the German Association of the Scientific Medical Societies was updated between 2020 and 2022. This article describes the essence of the new chapter "Stop the bleed-prehospital" and the revised chapter "Coagulation management and volume therapy".

[Peripartum hemorrhage, diagnostics and treatment : Update of the S2k guidelines AWMF 015/063 from August 2022]

The current S2k guidelines on the diagnostics and treatment of peripartum hemorrhage are summarized in this article from the perspective of anesthesiology based on a fictitious case report. The update of the guidelines was written under the auspices of the German Society of Gynecology and Obstetrics with the participation of other professional societies and interest groups from Germany, Austria and Switzerland and published by the AWMF in 2022 under the register number 015/063.

[Hypovolemic and hemorrhagic shock]

The term "shock" refers to a life-threatening circulatory failure caused by an imbalance between the supply and demand of cellular oxygen. Hypovolemic shock is characterized by a reduction of intravascular volume and a subsequent reduction in preload. The body compensates the loss of volume by increasing the stroke volume, heart frequency, oxygen extraction rate, and later by an increased concentration of 2,3-diphosphoglycerate with a rightward shift of the oxygen dissociation curve. Hypovolemic hemorrhagic shock impairs the macrocirculation and microcirculation and therefore affects many organ systems (e.g. kidneys, endocrine system and endothelium). For further identification of a state of shock caused by bleeding, vital functions, coagulation tests and hematopoietic procedures are implemented. Every hospital should be in possession of a specific protocol for massive transfusions. The differentiated systemic treatment of bleeding consists of maintenance of an adequate homeostasis and the administration of blood products and coagulation factors.

[Management of hemorrhage in patients treated with direct oral anticoagulants]

The introduction of nonvitamin K antagonistic, direct oral anticoagulants (DOAC) made thromboembolic prophylaxis easier for patients. For many physicians, however, there is still uncertainty about monitoring, preoperative discontinuation, and restarting of DOAC therapy. Guidelines for the management of bleeding are provided, but require specific therapeutic skills in the management of diagnostics and therapy of acute hemorrhage. Small clinical studies and case reports indicate that unspecific therapy with prothrombin complex concentrates (PCC) and activated PCC (aPCC) concentrate may reverse DOAC-induced anticoagulation. However, PCC or aPCC at higher doses potentially provoke thromboembolic complications. However, idarucizumab, a specific, fast-acting, antidote for dabigatran, provides immediate and sustained reversal with no intrinsic or prohemostatic activity. This review article provides an overview of the pharmacology and potential risk of DOAC and the management in the perioperative period with a focus of current concepts in the treatment of DOAC-associated bleeding.

[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.

[Care for severely injured persons : Update of the 2016 S3 guideline for the treatment of polytrauma and the severely injured]

In 2011 the first interdisciplinary S3 guideline for the management of patients with serious injuries/trauma was published. After intensive revision and in consensus with 20 different medical societies, the updated version of the guideline was published online in September 2016. It is divided into three sections: prehospital care, emergency room management and the first operative phase. Many recommendations and explanations were updated, mostly in the prehospital care and emergency room management sections. These two sections are of special interest for anesthesiologists in field emergency physician roles or as team members or team leaders in the emergency room. The present work summarizes the changes to the current guideline and gives a brief overview of this very important work.

[Coagulation therapy in multiple trauma without point-of-care testing]

Analysis of blood coagulation with thrombelastometry (ROTEM™) and thrombelastography (TEG™) and analysis of thrombocyte function by a Multiplate™ assay is possible in only a few hospitals in Germany. Recently, the grade of recommendation (GoR) for point-of-care (POC) testing in official guidelines was increased and is now classified as GoR 1C. If a POC-based option is not available alternatives must be used. Besides blood products (RBC, FFP, TC), coagulation factor concentrates are used to treat trauma-induced coagulopathy. The benefits of therapy with factor concentrates are fewer immunological and infection side effects as well as faster effects after administration of specific coagulation factors. A good outcome in patients with multiple trauma is only possible by an adequate transfusion regime and administration of coagulation factors.

[Dealing with massive bleeding and associated perioperative coagulopathy: recommendations for action of the German Society of Anaesthesiology and Intensive Care Medicine]

Massive bleeding with coagulopathy and hemorrhagic shock poses a potential threat to life in numerous clinical settings. Optimal treatment including the prevention of exsanguination necessitates a standardized and interdisciplinary approach. Several studies have shown the importance of massive transfusion protocols and standardized coagulation algorithms to improve survival of severely bleeding patients and to avoid secondary complications. Thus, the Helsinki declaration for patient safety in anesthesiology demands the implementation of clinical practice guidelines for the treatment of patients requiring massive transfusion. This paper introduces a standardized algorithm for the treatment of patients with massive bleeding which was developed in consensus with the German Society of Anaesthesiology and Intensive Care Medicine (DGAI).

Thromboelastometry guided therapy of severe bleeding. Essener Runde algorithm

Both, severe haemorrhage and blood transfusion are associated with increased morbidity and mortality. Therefore, it is of particular importance to stop perioperative bleeding as fast and as possible to avoid unnecessary transfusion. Viscoelastic test (ROTEM® or TEG®) allow for early prediction of massive transfusion and goal-directed therapy with specific haemostatic drugs, coagulation factor concentrates, and blood products. Growing consensus points out, that plasma-based coagulation screening tests like aPTT and PT are inappropriate for monitoring coagulopathy or guide transfusion therapy. Increasing evidence of more than 5000 surgical or trauma patients points towards the beneficial effects of a thrombelastography or -metry based approach in diagnosis and goal-directed therapy of perioperative massive haemorrhage. The Essener Runde task force is a group of clinicians of various specialties (anaesthesiology, intensive care, haemostaseology, haematology, internal medicine, transfusion medicine, surgery) interested in perioperative coagulation management. The ROTEM diagnostic algorithm of the Essener Runde task force was created to standardise and simplify the interpretation of ROTEM® results in perioperative settings and to present their possible implications for therapeutic interventions in severe bleeding. To exemplify, this text mainly focuses on coagulation management in trauma.

Survey on the use of oxytocin for cesarean section

BACKGROUND

The administration of oxytocin at high doses during cesarean section may cause severe cardiovascular complications. However, a dosage as low as 1 IU has been proven to suffice. Bolus administration is not superior to infusion and causes more severe side effects. The purpose of this survey was therefore to determine dosages and routes of administration of oxytocin during cesarean section in Germany.

METHODS

A questionnaire was sent to 709 departments of anesthesiology. The questionnaire asked about the standard dosage of oxytocin and route of administration (bolus and/or slow infusion) used for cesarean section.

RESULTS

A total of 360 questionnaires (50.8%) were returned; 346 of these were filled out and therefore analyzed (accounting for approximately 329,000 births). It was found that 295 (85.3%) departments administer oxytocin as a bolus, and 48 (13.9%) give it only as a slow infusion. A bolus of 1-3 IU is administered at 176 departments (51.8%), 5-9 IU at 71 (20.9%), 10 IU at 39 (11.6%), and 12-40 IU at 6 (1.8%). Additionally, 3-9 IU were slowly infused at 56 departments (16.7%), 10 IU at 174 (50.3%), 12-20 IU at 51 (14.7%), and 23-40 IU at 22 (6.4%). The median cumulative oxytocin dose is 13 IU, ranging from 1 to 80 IU.

CONCLUSION

Most of the responding departments give oxytocin as a bolus at a relatively low dose. However, despite the potentially fatal side effects, one out of eight departments administers 10 IU or more as a bolus.

Blutungen während der Schwangerschaft

Hemorrhaging during pregnancy is often fulminant and life-threatening for mother and child. Of maternal deaths occurring during pregnancy, 25% are caused by hemorrhaging. All physicians involved in the interdisciplinary treatment of hemorrhaging during pregnancy need to be familiar with the specific pathophysiology of hemostatic changes during pregnancy, e.g. elevated hemostatic capacity, reduced anti-coagulation activity and severe alterations of the fibrinolysis system. Therapists must be able to perform a consequent, goal-directed interdisciplinary approach to prevent adverse maternal and fetal outcomes. The major issues of therapy are causal obstetric treatment of the bleeding, early detection and therapy of hyperfibrinolysis, optimization of fibrinogen and platelet levels and knowledge of the possibilities of a targeted coagulation therapy.

Interleukin-6 enhancement after direct autologous retransfusion of shed thoracic blood does not influence haemodynamic stability following coronary artery bypass grafting

BACKGROUND

Direct autologous retransfusion of shed thoracic blood is carried out to reduce homologous transfusion after cardiac surgery, but it contains high concentrations of inflammatory mediators. The purpose of the study was to investigate whether retransfusion of shed thoracic blood induces plasma interleukin-6 (IL-6) expression and influences haemodynamics.

METHODS

Following uncomplicated coronary artery bypass graft surgery, forty-four patients were randomised in case postoperative blood loss via thoracic drains exceeded 350 ml. The course of plasma IL-6 levels and haemodynamics including cardiac output, extravascular lung water and intrathoracic blood volume were investigated prior to (T0), 30 minutes (T1), 1 (T2), 3 (T3) and 12 hours (T4) after retransfusion of 350 ml shed blood in comparison to 350 ml saline.

RESULTS

Plasma IL-6 levels at T1 (1892 +/- 202 vs. 485 +/- 30 pg/ml) and T2 (1059 +/- 119 vs. 413 +/- 30 pg/ml) were significantly higher in the verum group (n = 20) compared to controls (n = 24) ( P < 0.01). Severe haemodynamic side effects were not detected.

CONCLUSION

This study found significantly elevated plasma IL-6 levels following direct autologous retransfusion of shed thoracic blood but failed to show severe adverse effects affecting haemodynamic stability.

Rahmenbedingungen für eine intakte Hämostase

A coagulopathy is an independent predictor of perioperative mortality. Therefore, maintenance of a functional coagulation system is an essential precondition to reduce morbidity and mortality in the perioperative setting. Sound coagulability also depends on prerequisites such as body temperature, acid-base balance, plasma calcium concentration and haematocrit. Severe trauma or perioperative bleeding can gravely influence these factors and boost the blood loss. Common global tests of coagulation are not helpful in this setting because they are conducted on plasma with a normalised temperature of 37 degrees C, an excess of calcium and a stabile acid-base balance. Hence, knowledge of the effects of altered prerequisites is a premise to avoid a possibly lethal coagulopathy. According to the current literature, an increased risk for clinically significant coagulopathy exists with a body temperature <or=34 degrees C, an acidosis <or=7.15, ionised calcium under 0.9 mmol/l or a haematocrit under 30-35%. A combination of these factors deteriorates the coagulopathy and hypothermia in addition to acidosis is especially harmful. Prevention of derangement of these factors should start as early as possible, i.e. in trauma patients at the scene of the accident and should be continued in the operating room.

[Diving accidents. Emergency treatment of serious diving accidents]

Decompression injuries are potentially life-threatening incidents mainly due to a rapid decline in ambient pressure. Decompression illness (DCI) results from the presence of gas bubbles in the blood and tissue. DCI may be classified as decompression sickness (DCS) generated from the liberation of gas bubbles following an oversaturation of tissues with inert gas and arterial gas embolism (AGE) mainly due to pulmonary barotrauma. People working under hyperbaric pressure, e.g. in a caisson for general construction under water, and scuba divers are exposed to certain risks. Diving accidents can be fatal and are often characterized by organ dysfunction, especially neurological deficits. They have become comparatively rare among professional divers and workers. However, since recreational scuba diving is gaining more and more popularity there is an increasing likelihood of severe diving accidents. Thus, emergency staff working close to areas with a high scuba diving activity, e.g. lakes or rivers, may be called more frequently to a scuba diving accident. The correct and professional emergency treatment on site, especially the immediate and continuous administration of normobaric oxygen, is decisive for the outcome of the accident victim. The definitive treatment includes rapid recompression with hyperbaric oxygen. The value of adjunctive medication, however, remains controversial.

[Patent foramen ovale: an underrated risk for divers?]

The foramen ovale which is the fetal connection between the right and left atrium persists in about 30 % of the adult population. In the presence of a persistent foramen ovale (PFO) shunting of blood may occur from the right to the left atrium, and bubbles can reach the systemic circulation during or after the decompression phase of a dive with compressed air. Therefore, divers with PFO may have an increased risk to develop ischemic cerebral lesions and neurologic decompression sickness (DCS). Significant right-to-left shunting may be diagnosed using transcranial doppler ultrasound of the medial cerebral artery and echocardiography with echo contrast media and Valsalva provocation. However, there are no official guidelines concerning PFO screening in medical fitness exams for professional or recreational divers in Germany. Therefore, it remains in the diver's choice to be screened for PFO. Divers with a history of DCS should be monitored for PFO, especially when diving strictly adhered to decompression tables. Divers with PFO who refuse to stop diving after DCS should be advised to adhere to very save dive profiles.

[Failed spinal analgesia after a combined spinal epidural anaesthesia for Caesarean section]

A case of failed spinal analgesia with a combined spinal epidural anaesthesia (CSE) for Caesarean section is described. The lack of desired effect following an inconspicuous spinal, epidural or combined regional anaesthesia by an experienced anaesthetist is a rare and unexpected event. Especially when repeatedly observed in one patient,one should consider modified anatomical conditions of the affected spinal regions. We discuss the differential diagnosis which consists of inherent and acquired modification of tissue, neoplasia and vascular or infectious diseases. This case also confirms that not every adverse event after spinal or extradural anaesthesia is necessarily caused by the puncture.

Isoflurane, nitrous oxide, and fentanyl pharmacodynamic interactions in surgical patients as measured by effects on median power frequency

STUDY OBJECTIVE

To identify and quantify the simultaneous interactions of isoflurane, nitrous oxide (N2O), and fentanyl during surgical procedures. The slowing of the EEG to a median power frequency of 2 Hz to 3 Hz was chosen as the measure of pharmacodynamic drug effect.

DESIGN

Prospective, randomized, open label.

SETTING

Operating room of a university hospital.

PATIENTS

65 ASA physical status I and II patients undergoing gynecological laparatomies.

INTERVENTIONS

25 patients received no fentanyl. 20 patients received a loading dose of 100 micrograms fentanyl and a continuous infusion of 70 micrograms.h-1 fentanyl. Calculated effect compartment concentrations were 0.7 ng.ml-1 between the first and second hours after induction of anesthesia. Another 20 patients received a loading dose of 200 micrograms fentanyl and a continuous infusion of 150 micrograms.h-1 fentanyl; the respective effect compartment concentrations were 1.5 ng.ml-1. N2O was randomly administered in concentrations of 0, 20, 40, and 60 vol%; in the group that did not receive fentanyl, we additionally investigated 75 vol% N2O. Each patient received two different N2O concentrations, with each combination of N2O and fentanyl finally applied to ten patients. Isoflurane vaporizer settings were chosen so that the median power frequency was held between 2 Hz and 3 Hz. The type and degree of interaction among the three anesthetic drugs was analyzed based on a generalized isobole approach.

MEASUREMENTS AND MAIN RESULTS

The interaction of isoflurane, N2O, and fentanyl is compatible with additivity. A model with regard to the relative potencies and age dependency is given by: [formula: see text] with C0,iso = 1.30 vol%, C0,N2O = 177 vol%, C0,fen = 10.6 ng.ml-1, and a = -0.0031 yr-1. where conc. = end-tidal or effect compartment concentrations.

CONCLUSION

The potency of N2O and fentanyl to substitute isoflurane in maintaining a median power frequency of 2 Hz to 3 Hz during surgery is less than anticipated from minimum alveolar concentration studies.