Trauma Flashcards
What are indications for activation of the MTP?
- Replacement of 50% of patients blood volume in 1 hour
- Replacement of 100% blood volume in 24h
Requiring
- 4 units in 1 hour
- 10 units in 24 hours
Can use various scoring systems of which there are numerous and these vary in criteria and significance. e.g. TASH (Trauma Associated Severe Haemorrhage) score is most well validated if using exam, labs and FAST scan. It requires lab results (hemoglobin and base excess), which may delay the decision to initiate massive transfusion longer than scores that require only clinical parameters
What is a grading system for pancreatic trauma?
American Association for the Surgery of Trauma (AAST)
Proximal pancreas is defined as the gland to the right of the SMV-portal vain axis. Distal is to the left. Deep refers to down to level of the duct.
Grade 1: haematoma with minor contusion or superficial laceration without duct injury
Grade 2: Major contusion or laceration without duct injury
Grade 3: Distal transection or deep parenchymal injury with duct injury
Grade 4: Proximal transection or deep parenchymal injury involving the ampulla and or intrapancreatic CBD.
Grade 5: Massive disruption of the pancreatic head “shattered pancreas”.
What is the MTP?
It varies slightly between institutions however the general principles are that the MTP is a protocol of blood loss replacement with a balanced
1:1:1 ratio between RBC, plts and FFP in patients with significant and ongoing blood loss with regular monitoring of ABG and coagulation and 10ml CaCl with every pack
The first box is often unmatched O neg blood and follow up boxes are matched to Group and hold results.
It continues until deactivated and stopped. It requires ongoing clear communication pathways between involved clinicians, orderlies and blood bank.
Classes of haemorrhagic shock
What is meant by permissive hypotension?
Permissive hypotension is a deliberate strategy to maintain blood pressure at lower-than-normal levels in patients with trauma or hemorrhage.
The goal of this treatment is to maintain organ perfusion without exacerbating bleeding, which can occur with aggressive fluid resuscitation.
Initial goal SBP: ≥ 70 mmHg until definitive haemostasis achieved.
It is contraindicated in traumatic brain injury where SBP needs to be 100-110 to reduce chance of secondary brain injury
What is haemorrhagic shock?
Inadequate oxygen delivery & tissue perfusion due to blood loss. A form of hypovolaemic shock.
What is the pathophysiology of haemorrhagic shock?
Organ level:
- hypovolaemia and reactive vasoconstriction results in end organ hypoperfusion and damage.
- hypoperfusion of brain and myocardium can lead to cerebral anoxia and arrhythmias that can lead to death in mins.
Cellular level:
What is the lethal triad of trauma?
Hypothermia
Acidosis
Coagulopathy
When would you use IO access? and it what location?
When gaining intravenous access is unattainable or difficult to secure then IO can be used. In children preferred location is proximal tibia followed by distal femur. In adults sternum or proximal tibia.
What are some relative contraindications to emergent cricothyroidotomy where one would otherwise be indicated? And what alternatives would you do in these scenarios?
Children <10 years old. Membrane small, cartilage very soft and difficult to palpate. Perform needle cricothyroidotomy instead as a bridge to definitive endotracheal intubation or tracheostomy.
Severe neck trauma and difficult to establish landmarks
Known tumour, narrowing, scarring from pre-existing subglottic surgery.
Describe the procedural steps of an emergent cricothyroidotomy.
- Palpate landmarks:
- Thyroid cartilage
- Cricoid cartilage - Stabilise upper airway with dominant hand.
- Midline vertical incision (to minimise bleeding) Size 10 blade.
- Palpate through incision the cricothyroid membrane
- Incise the membrane
- Dilate with trosseaus
- Place bougie and tracheostomy tube.
What are some possible complications of cricothyroidotomy?
- Bleeding
- Pneumothorax
- Thyroid cartilage fracture can lead to vocal cord dysfunction
- Tracheal stenosis
Describe the pathophysiology of trauma induced coagulopathy.
Mechanisms:
1. Activated Protein C
- Anticoagulant – inactivates Factors Va and VIIIa.
- Increased activity in trauma possibly due to upregulation of Thrombomodulin activity in the setting of hypoperfusion.
- Endothelial Glycocalyx Layer (EGL)
- “Shedding” of EGL after injury due to yet undetermined mechanisms
- Anticoagulant components such as chondroitin sulfate and heparin sulfate - Increased Fibrinolysis
- Clotting cascade activated locally
- Distant fibrinolytic activity increased
- Believed to prevent microvascular thrombosis. - Platelet Impairment
- Numbers are Depleted
- Migration is Decreased
- Function is Impaired - The Lethal Triad (Hypothermia, Acidosis, & Coagulopathy) creates a positive feedback loop resulting in significantly increased mortality.
When performing resuscitation what are the possible outcomes and what class of haemorrhagic shock are they likely to represent?
- Rapid Responder indicates class 1
- Transient Responder indicates class 2-3
- Non-Responder indicates class 4.
What is TEG and how is it used in haemorrhage scenarios?
Stands for thrombelastogram and it assess the viscoelastic properties of clot formation in real time.
It is used to allow for more rapid goal-directed resuscitation with blood products.
What is the grading for splenic trauma and how would you manage each grade?
Management depends on patient stability and other injuries more than the grade per se.
If patient unstable and/or peritonitic then warrants laparotomy. Diffuse peritonitis indicates bowel injury (haemoperitoneum alone doesn’t usually cause this).
If transient responder than angioembolisation.
If stable then CT and if active extravasation or pseudoaneurysm then angioembolisation.
If stable and no active extravasation or angioembolisation then bed rest for 24-48 hours and restricted activity for grade of injury + 2 weeks (usually 1-4 months) and longer off contact sports.
If in laparotomy for other indications then
- grade 1 can leave alone or if small minor bleeding haemostatic agents.
- grade 2/3 splenorrhaphy usually need pledgets or mesh or consider partial splenectomy.
- grade 4/5 splenectomy.
