Basics Flashcards
What is the distribution of mortality from trauma?
Trimodal
1) Immediate (50% of all deaths)
- Massive brain injuries
- Great vessel injuries
- Airway occlusion
- Cord transection
- Exanguination
2) Early (30% of all deaths) - minutes to hours “golden hour”
- Uncontrolled blood loss
- 2ndry CNS damage
3) Late Phase (20%) - days to weeks
- Sepsis
- MODS
In deceleration injuries, which structures are at risk of being avulsed from the site at which they are anchored?
1) C - spine
2) Brain
3) Main Bronchus
4) Thoracic Aorta
5) Renal vessels
6) Transverse Mesocolon
What is a crush injury?
Injury + sustained compression of tissues
causing ischaemia & muscle necrosis
What are the complications of crush injuries?
1) Fluid loss
2) Rhabdomyolysis - myoglobin release from muscles
3) DIC
4) Release of toxins from muscles
5) Acute tubular necrosis
6) Renal failure
In trauma, which type of shock is the cause of the hypotension (until proven otherwise)?
Hypovolaemia
Cellular destruction in hypovolaemic shock, what changes does the acidosis cause?
1) Disruption of Na+/K+ pump
Na+ accumulates => cell swells => intercellular spaces enlarge => fluid 3rd spacing => disruption of organ integrity
How do you calculate cardiac output?
CO = SV x HR (normal is 6L/min)
How do you calculate SBP?
SBP = DBP + PP
In Hypovolaemic shock, what is seen in the following parameters?
1) HR
2) CVP/PAOP
3) CO
4) SV
5) SVR
1) HR - Increased
2) CVP/PAOP - Decreased
3) CO - Decreased
4) SV - Decreased
5) SVR - Increased
In Cardiogenic shock, what is seen in the following parameters?
1) HR
2) CVP/PAOP
3) CO
4) SV
5) SVR
1) HR - Increased
2) CVP/PAOP - Increased
3) CO - Decreased
4) SV - Decreased
5) SVR - Increased
In Septic shock, what is seen in the following parameters?
1) HR
2) CVP/PAOP
3) CO
4) SV
5) SVR
1) HR - Increased
2) CVP/PAOP - Decreased
3) CO - Increased
4) SV - Decreased
5) SVR - Decreased
In cardiac tamponade shock, what is seen in the following parameters?
1) HR
2) CVP/PAOP
3) CO
4) SV
5) SVR
1) HR - Increased
2) CVP/PAOP - VERY Increased
3) CO - Decreased
4) SV - Decreased
5) SVR - Increased
In neurogenic shock, what is seen in the following parameters?
1) HR
2) CVP/PAOP
3) CO
4) SV
5) SVR
1) HR - Decreased
2) CVP/PAOP - -
3) CO - Decreased
4) SV - -
5) SVR - Decreased
What are the main features of class 1 shock?
Volume loss 0-750mls
15% loss
Restless
BE 0 - -2
What are the main features of class 2 shock?
Volume loss 750-1500mls 15-30% loss HR> 100 Pulse Pressure Decreased Urine 20-30mls/h RR 20-30 Anxious BE -2 - -6
What are the main features of class 3 shock?
Volume loss 1500-2000mls 30-40% loss HR> 120 BP Decreased Pulse pressure Decreased Urine 5 - 15ml/h RR 30-40 Anxious/Confused BE -6 - -10 Must give BLOOD
What are the main features of class 4 shock?
Volume loss >2000mls >40% loss HR> 140 BP Decreased Pulse Pressure Decreased Urine Anuric RR >40 Confused/Lethargic BE > -10 Must give BLOOD
What is the immediate management of hypovolaemic shock?
Control bleeding
1) Direct Pressure
2) Elevation of injured limb
3) Head down tilt
Establish IV access - 2 16-gauge cannulas
1) Forearm antecubital veins
2) Cut down to Great Sapehnous vein
3) IO Access for <6yrs kids
* CENTRAL ACCESS ONLY WHEN STABLE*
Fluid replacement & identify cause for hypovolaemia
Which situations may CVP be falsely raised?
1) Tension penumothorax
2) Pericardial Effusion
3) Air embolus
4) MI
Which situations can physiological responses be distorted?
B Blockers Opiates IHD Pacemakers Pre-hospital fluid resus Pneumatic anti-shock garments Spinal Injury Head injury
What are transient responders?
Given fluid bolus and immediately improves => then deteriotates
THINK ONGOING BLOOD LOSS
Which of the following parameters can you measure patient response to successful fluid resusitation?
1) Pulse
2) BP
3) Skin colour
4) CNS state
What metabolic changes are seen initially in hypovolaemic shock?
Respiratory alkalosis - due to high RR
What metabolic changes are seen later on in hypovolaemic shock?
Metabolic acidosis - uncompensated tissue hypoperfusion/insufficient fluid replacement => anaerobic metabolism
On VBG:
- lower pH
- progressive base deficit
- low bicarbonate
What spaces can major blood loss be found?
1) Chest
2) Abdo
3) Pelvis - use pelvic binder
4) Long bones - use splint
5) On the floor
What causes neurogenic shock?
Injury to descending sympathetic pathways
(T2-T6 for heart)
Loss of vasomotor tone with pooling in veins
Inability to go into tachycardia
Treat this with selective ionotropes & atropine
What is the endocrine response to trauma?
Stimulates Ascending reticular formation & limbic system =>
stimulates Hypothylamus =>
Anterior Pituitary => ACTH, GH, Prolactin
Posterior Pituitary => ADH
ACTH => Cortisol & Aldosterone
What is the immunological response to trauma?
1) Raised Temp
2) Raised WCC
3) Raised IgG
Why is there a lucid interval in younger people in extradural bleeds?
Expanding haematoma is being accomodated in extradural bleeds
Why is there a rapid decompensation in young people after lucid interval?
ICP rises as the inner edge of temporal lobe descends into tentorial opening
Extradural haematomas are limited by what structure in the skull?
Suture lines
What is normal ICP?
10mmHg
What is abnormal ICP?
> 20mmHg
In the situation of raised ICP, why does muscle weakness manifest?
corticospinal tract decompression
What is Cushings Triad?
1) Decreased RR
2) Decreased HR
3) Widened Pulse Pressure - high systolic & low diastolic
How do you measure cerebral perfusion pressure?
CCP = MAP - ICP
Increased cerebral blood flow is caused by?
1) Raised CO2
2) Raised extracellular K+
3) Decreased pO2
How do you calculate MAP?
(systolic + 2(diastolic))/3
How to manage raised ICP (non-surgical management)?
1) Maintain normal PCO2 (3.5-4.0)
2) Monitor with ICP bolt & transducer
3) Aim to maintain CPP at 60-70mmHg (fluids/ionotropes)
4) Maintain ICP of 10mmHg with
a) Mannitol
b) Hyperventilation to PCO2 4.5kPa
c) Thiopental infusion
d) Hypothermia
5) Emergency burr holes / craniotomy
