Trauma/Haemorrhage Flashcards
Cardiac output
L/min Stroke volume (ml/beat) x heart rate (b/min)
Preload
Volume of venous return to left and right sides of heart
Determined by:
Venous capacitance
Volume status
Pressure difference between mean venous pressure and mean atrial pressure
Stroke volume
Preload
Myocardial contractility
Afterload
Afterload
Peripheral vascular resistance
Frank-Starling Law
Stroke volume of heart increases in response to increased volume of blood in ventricles.
Increased volume into ventricle stretches cardiac muscle, leading to increased force of contraction.
Types of shock
Hypovolaemic
Cardiogenic
Obstructive
Distributive (Neurogenic)
Hypovolaemic shock
Haemorrhage (traumatic, non-traumatic) Fluid loss (Gi losses, Burns, diuresis, pancreatitis)
Classes of haemorrhage
Class I
Class II
Class III
Class IV
Class I
Blood loss: <750ml (15%) BP: Normal HR: Normal RR: Normal GCS: Normal Urine: >30ml/hr
Class II
Blood loss: 750-1500 (15-30%) BP: normal (reduced pulse pressure) HR: 100-120 RR: 20-30 GCS: mild anxiety Urine: 20-30ml/hr
Class III
Blood loss: 1500-2000ml (30-40%) BP: Systolic <100 HR: 120-140 RR: 30-40 GCS: confused Urine: 20ml/hr
Class IV
Blood loss: >2000ml (>40%) BP: Systolic <70 HR: >140 RR: >40 GCS: reduced GCS Urine: Negligible
Cardiogenic shock
Impaired contractility (MI, Myocarditis, myocardial contusion) Dysrhythmia (tachycardias, bradycardias) Valvular diysfunction (severe aortic regurgitation/stenosis) Left ventricular outflow tract obstruction (HOCM, left atrial myxoma)
Obstructive shock
Massive PE Atrial thrombus/myxoma Emboli (e.g. air embolus) Cardiac tamponade Abdominal compartment syndrome Tension pneumothorax Dynamic hyperinflation (severe asthma) Caval compression (supine hypotension syndrome in pregnancy)
Distributive Shock
Sepsis Anaphylaxis Neurogenic shock Liver failure Adrenal insufficiency
Neurogenic shock
Complication of spinal cord injury
Hypotension, bradycardia, temperature dysregulation
Above T6
Descending sympathetic tracts disrupted. Loss of sympathetic tone and unopposed parasympathetic response
Liver Injury Grading
American Association for Surgery of Trauma (AAST) Liver Injury Scale
AAST Liver Scale: Grade I
Haematoma: sub capsular <10% of surface area
Laceration: capsular tear, <1cm parenchymal depth
AAST Liver Scale: Grade II
Haematoma: subcapsular: 10-50% surface area
Haematoma: intraparenchymal <10cm diameter
Laceration: capsular tear. 1-3cm Parenchymal depth, <10cm length
AAST Liver Scale: Grade III
Haematoma: subcapsular >50% surface area
Haeamatoma: intraprenchymal >10cm
Laceration: capsular tear. >3cm parenchymal depth
Vascular: injury with active bleeding contain within liver parenchyma
AAST Liver Scale: Grade IV
Laceration: parenchymal disruption 25-75% hepatic lobe
Vascular: injury with active bleeding breaching liver parenchyma into peritoneum
AAST Liver Scale: V
Laceration: parenchymal disruption >75% of hepatic lobe
Vascular: juxtahepatic venous injuries (retrohepative vena cava/central major hepatic veins)
Splenic Injuries
AAST Splenic Injury Scale
Grade 1-5
AAST Splenic Injury Scale: Grade 1
Capsular tear <1cm parenchymal depth
Subcapsular haematoma <10% surface area
AAST Splenic Injury Scale: Grade 2
Capsular tear 1-3cm parenchymal depth
Subcapsular 10-50% surface area, or intraparenchymal <5cm
AAST Splenic Injury Scale: Grade 3
Capsular tear >3cm parenchymal depth, or any tear involving trabecular vessels
Subcapsular >50% surface area, or intraparenchymal >5cm, or any expanding or ruptured haematoma.
AAST Splenic Injury Scale: Grade 4
Laceration involving segmental or hilar vessels, devascularising >25% of the spleen
AAST Splenic Injury Scale: Grade 5
Completely shattered spleen or hilar vascular injury, devascularising the entire spleen
Kidney Injury
AAST Renal Trauma Classification
one grade up for bilateral injuries, up to grade III
AAST Renal Trauma Classification: Grade I
Contusion: microscopic or gross Haematuria, urologic studies normal
Haematoma: Subcapsular, non expanding without parenchymal laceration
AAST Renal Trauma Classification: Grade II
Haematoma: non expanding perirenal haematoma confirmed to renal retroperitoneum
Laceration: <1cm parenchymal depth without urinary extravagation
AAST Renal Trauma Classification: Grade III
Laceration: >1cm parenchymal depth or renal cortex without collecting duct rupture or urinary extravagation
AAST Renal Trauma Classification: Grade IV
Laceration: Parenchymal laceration extending through renal cortex, medulla and collecting system
Vascular: main renal artery or vein injury with contained haemorrhage
AAST Renal Trauma Classification: Grade V
Laceration: completely shattered kidney
Vascular: avulsion of renal hilum devascularising kidney
