Minutes of the Liverpool Society of Anaesthetists Joint Meeting with the Section of Anaesthesia of the Manchester Medical Society
Thursday 17th March 2016
The meeting was opened by the President of the LSoA Dr Ewen Forrest who welcomed members from the Liverpool Society of Anaesthetists and the Section of Anaesthesia of the Manchester Medical Society. He introduced the first speaker.
‘Coagulation & its Modification’
Dr Gillian Brearton, Consultant Haematologist, Countess of Chester Hospital.
Dr Brearton started her talk by explaining how coagulation is affected by different situations. She provided some revision talking the audience through the clotting cascade, explaining that this is an oversimplification, but that a more realistic view is that coagulation state is one of balance and that normally we tend to lean towards the more anti-coagulated side. She explained the role of tissue factor in initiating coagulation, how cytokines & endotoxins lead to up-regulation, the consequent amplification effects and how the clot propagates and platelets are activated. Dr Brearton talked about how sepsis and DIC lead to loss of localisation of clotting system control, leading to natural down-regulation of anticoagulant pathways, generation of thrombi, obstruction of vessels and consumption of clotting factors and platelets. She talked about the clinical picture and when to correct abnormal clotting in septic patients. Coagulation in pregnancy was the next variant she discussed, explaining that the parturient tends to be more coagulant due to increase in clotting factors 7, 8 & 9 and a down regulation of protein S. She talked about major obstetric haemorrhage and how low fibrinogen levels can be extreme in placental abruption and placenta acreta and that it is important to assess fibrinogen levels early. She spoke about the consideration of TEG/ROTEM testing and cryoprecipitate and platelet transfusion. Dr Brearton told the audience about iatrogenic coagulation issues and explained how different antiplatelet agents worked. She explained the different mechanisms of action of direct acting oral anticoagulants (DOACs) and how conventional clotting testing can help determine drug activity. She explained the treatment of major and life threatening haemorrhage in patients on DOACs and talked about Idarucizumab, the new antidote available for Dabigitran and how antidotes are in development for Apixaban and Rivoroxaban. She then took some questions from the floor.
‘Where’s the Point of Care?'
Dr David Castillo, Countess of Chester Hospital
Dr Castillo explained that his talk was on how viscelastometric point of care testing can help us achieve haemostasis. He said it has become a hot topic and even entered the Royal College of Anaesthetists’ Curriculum. He said the tests can help you answer the question ‘In a bleeding patient with a coagulopathy what haemostatic therapy should I use?’ Dr Castillo explained with the aid of TEG & ROTEM graphs how these tests can show clot strength, clotting time, whether there is an issue with platelets or clotting factors. The tests give quick results and aid targeted transfusion so avoiding blood product wastage. He said the tests are not a magic bullet; they will not fix a traumatic amputation or an atonic uterus, nor are they good for monitoring drug therapy or identifying inherited disorders of coagulation. He explained in detail how the ROTEM and TEG machines work and explained the evidence for viscelastometric testing. He said NICE (Guidance no.13 2014) have recommended its use in cardiac surgery based on review of randomised control trials with rigid algorithms, but that it has not recommended its use in trauma or obstetrics. He pointed out that when trying to validate viscelastometric tests it is difficult as you are not comparing like for like testing so flawed comparisons are made. Dr Castillo said there have been many changes in the way trauma has been managed over the last few years (e.g. damage control surgery, permissive hypotension, introduction of shock packs) and so they are still working out the best way to manage massive haemorrhage. He touched on the dangers of transfusion such as transfusion associated circulatory overload (TACO) and transfusion related acute lung injury (TRALI). Dr Castillo pointed out that it is not the monitoring that makes the difference but the intervention and he gave several examples of research in obstetrics, trauma and spinal surgery where viscelastometric testing has helped to guide transfusion with positive outcomes. He then went through a few case examples where ROTEM had been used by his colleagues in Chester and using the ROTEM graphs demonstrated how ROTEM guided transfusion had led to a positive patient outcome. He then took some questions from the floor.
Blood Components and Major Haemorrhage
Dr Paula Bolton-Maggs, Medical Director of the Serious Hazards of Transfusion (SHOT) Group
Dr Bolton-Maggs started her talk by explaining the causes of coagulation in trauma, the functions of thrombin and how we should not think of coagulation as a ‘cascade’ but as more of a ‘dance’.
She talked about haemostatic resuscitation, gaining early control, allowing permissive hypotension, limiting crystalloid infusion and targeting coagulopathy with tranexamic acid and blood products. Dr Bolton-Maggs spoke about the development of major haemorrhage protocols (MHP), with the first use of 1:1:1 product use by the military and consequent use in civilian trauma showing decreased mortality. She said, however, that there are very few studies that support 1:1:1 use in non-trauma patients but that this practice has spread causing problems such as TACO. She talked about the use of tranexamic acid and the clear benefit in bleeding patients and also the on-going trials looking into its use in specific areas, e.g. The WOMAN trial in major obstetric haemorrhage and the HALT-IT trial in acute gastrointestinal bleeding. She expanded further on MHPs and their provision for a prompt and coordinated response to haemorrhage. She warned against the consequences of giving FFP when not needed, e.g. causing TACO, and that activating the MHP unnecessarily may adversely affect the care of other patients by redirecting resources. She said there are different types of major haemorrhage e.g. military vs. civilian, blunt vs. penetrating trauma, post cardiac surgery bleeding, GI bleeding, PPH, which all need their own specific management. She talked about the 6 ‘T’s: TRIGGERING the MHP, making sure the whole TEAM is trained in how the MHP works, giving TRANEXAMIC ACID, ensuring appropriate TESTING, e.g. ensure pre-transfusion samples are sent to the laboratory, complying with the SHOT recommendations for giving TRANSFUSION, e.g. checking patient ID, blood component, prescription etc. and notifying the laboratory when it’s TIME TO STOP. Dr Bolton-Maggs talked about the North-West MHP and the data from SHOT reporting detailing errors in wrong blood components given and delays in transfusion. She summarised her talk and took questions from the floor. She recommended the audience visit the British Committee for Standards in Haematology website for guidelines. http://www.bcshguidelines.com
‘Damage Limitation Surgery’
Major Jonathan Morrison, Glasgow.
Major Morrison started his talk explaining that mortality has decreased with the introduction of formalised trauma networks and reorganisation of trauma care. He described the role of damage limitation surgery (DLS) in decreasing the overall physiological insult of trauma and improving tolerance to injury and turning former ‘non-survivors’ into survivors. He spoke of the lethal triad of hypothermia, acidosis and coagulopathy and then highlighted other factors that contribute to injury tolerance such as premorbid health, injury burden, genetics and time to shock reversal, the latter being something we can alter. Major Morrison described the first formal approach to DLS in traumatic liver injuries where patients exsanguinated, practice changed to packing the liver and subsequent transfer to ICU to normalise physiology before definitive repair, which matured into accepted practice. He described the three (possibly four) stages of DLS or damage control surgery (DCS): (DCS 0- restriction of IV crystalloid fluids), DCS 1-Control of haemorrhage and contamination, DCS 2- Intensive care admission, DCS 3- Definitive surgery. He expanded on each of these aspects describing methods used in DCS-1 such as packing, leaving GI discontinuity, using staplers in cavities where you would not normally use them e.g. on the lungs and manoeuvres such as shunting. He said it is important to let ICU know if there has been any change in ‘plumbing’ during DLS. During the ICU admission the aim is cardiopulmonary optimisation, rewarming, coagulation correction and to anticipate complications such as bleeding and sepsis. During definitive surgery he described problems including multiple theatre trips and the high burden of morbidity patients can incur e.g. frozen abdomen. Major Morrison went onto describe how DCS fits into damage control resuscitation (DCR). He described a study he authored (Anaesthesia. 2013 Aug;68(8):846-50) where pH, coagulopathy and hypothermia were corrected before and after surgery in combat casualties. They showed that DCR could normalise physiological derangements caused by haemorrhagic shock improving outcome. He said the indications for DCS are decreasing due to better DCR. He finished his talk saying that the on-going establishment of trauma networks will decrease preventable deaths and allow sicker patients to make it to hospital. Major Morrison then took questions from the floor.
Dr Forrest thanked all the speakers and the Manchester Medical Society Anaesthesia Section President, Dr Donna Greenhalgh, then gave the vote of thanks and invited the audience back to next year’s joint meeting.
Dr Gemma Roberts, Honorary Secretary