Trauma Flashcards
How do you decide whether to use a nasopharyngeal or an oropharyngeal airway?
NPA if gag reflex is present, OPA if it isn’t (stop tongue swallowing)
Name 2 kinds of emergency surgical airways
Needle circothyroidotomy, surgical cric
What are the kinds of definitive airways and what is their advantage over non definitive airways?
No risk of aspiration.
Endotracheal tube or tracheostomy
What are the signs of a tension pneumothorax?
- Respiratory distress
- Raised JVP
- Low BP
- Tracheal deviation and displaced apex
- Decreased air entry and decreased VR
- Hyperresonant percussion
How do you treat a tension pneumothorax?
- Immediate decompression
- Large bore cannula into 2nd ICS, mid clavicular line
- Insert ICD later
What is the immediate management for an open sucking chest wound?
Convert it to a closed wound by covering itwith damp occlusive dressing stuck down on 3 sides
Which images are seen in a trauma series?
- C spine (lat and peg)
- CXR
- Pelvis
How do you assess C spine radiographs?
- View
- AP/lateral/open mouth peg view
- Adequacy
- Need to see C7-T1 junction
- May need swimmer’s view with abducted arm
- Alignment: 4 lines
- Anterior vertebral bodies
- Anterior vertebral canal
- Posterior vertebral canal
- Tips of spinous processes
- Bones: shapes of bodies, laminae, processes
- Cartilage: IV discs should be equal height
- Soft tissue: width of soft tissue shadow anterior to upper vertebrae should be 50% of vertebral width
What are the indications for C spine clearance?
NEXUS criteria:
- Fully alert and oriented
- No head injury
- No drugs or alcohol
- No neck pain
- No abnormal neurology
- No distracting injury
How much of the body’s mass is circulating blood volume?
7%
What % of blood volume do you have to lose before the mental state changes or blood pressure changes?
- 15-30% patient will be anxious but BP normal
- 30-40% confused and BP drop
- >40% patient will be lethargic and BP will have dropped a lot
What causes neurogenic shock?
Disruption of sympathetic nervous system
What are the causes of neurogenic shock?
- Spinal anaesthesia
- Hypoglycaemia
- Cord injury above T5
- Closed head injury
How does neurogenic shock present?
Hypotension, bradycardia, warm extremities
How do you manage neurogenic shock?
- Vasopressors: vasopressin and noradrenaline
- Atropine to reverse bradycardia
What causes spinal shock?
- Acute spinal cord transection
- Loss of all voluntary and reflex activity below the level of injury
How does spinal shock present?
- Hypotonic paralysis
- Areflexia
- Loss of sensation
- Bladder retention
Which chest injuries are life threatening?
ATOMIC:
- Airway obstruction
- Tension pneumothorax
- Open pneumothorax (sucking)
- Massive haemothorax
- Intercostal disruption and pulmonary contusion
- Cardiac tamponade
What counts as a massive haemothorax and what causes it?
>1.5L of blood in chest cavity, usually caused by disruption of hilar vessels
How does a massive haemothorax present?
- Signs of chest wall trauma
- Low BP
- Reduced expansion
- Reduced breath sounds and VR
- Stony dull percussion
How do you treat a massive haemothorax?
- Cross match 6 units
- Large bore chest drain with heparin saline for autotransfusion
- Thoracotomy if >1.5L or >200ml/hour
What is a flail chest?
Whee there are anterior or lateral #s of 2 or more adjacent ribs in 2 or more places. The flail segment moves paradoxically with respiration. Oxygenation decreases as a result of the underlying pulmonary contusion and decreased ventilation of the affected segment
What investigation findings indicate a flail chest?
- CXR/CT chest: pulmonary contusion (white)
- Serial ABGs: low PaO2:FiO2 ratio
How do you treat a flail chest?
- O2
- Good analgesia: PCA or epidural
- Persistent respiratory failure: PPV
How does cardiac tamponade occur from a trauma?
Usually from penetrating trauma. Disruption of myocardium or great vessels leads to blood in the pericardium, decreased filling and contraction, and therefore shock.
How does cardiac tamponade present?
- Beck’s triad
- Raised JVP/distended neck veins
- Low BP
- Muffled heart sounds
- Pulsus paradoxus: SBP fall of >10mmHg on inspiration
- Kussmaul’s sign: raised JVP on inspiration
- Intensely restless
What investigation findings indicate cardiac tamponade?
- US: FAST or transthoracic echo
- CXR: enlarged pericardium
- Raised CVP >12mmHg
- ECG: low voltage QRS ± electrical alternans
How do you manage cardiac tamponade?
Pericardiocentesis: spinal needle in R subxiphoid space aiming at 45 degrees towards the R tip of the left scapula. May need thoracotomy
Which ribs most commonly fracture?
5-9
What is the usual mechanism of injury if there is a fracture of the upper 4 ribs?
A high energy trauma
What are the possible complications of rib fractures?
Pneumothorax, lacteration of thoracic or abdominal viscera
How do you treat rib fractures?
Good analgesia:
- NSAIDs + opioids
- Intrapleural analgesia
- Intercostal block
What is the usual mechanism of injury for a sternal fracture?
Driver vs steering wheel
What is the risk with a sternal fracture?
Mediastinal injury
How do you treat sternal fractures?
- Analgesia, admit, observe
- Cardiac monitor
- Troponin: rule out myocardial contusion
What is the usual mechanism of injury for a pulmonary contusion?
Rapid deceleration injury or shock waves
What is the possible complication with a pulmonary contusion?
ARDS
How does a pulmonary contusion present?
Dyspnoea, haemoptysis, respiratory failure
What investigation findings are consistent with a pulmonary contusion?
Opacification on CXR and low PaO2:FiO2 ratio on serial ABGs
How do you treat a pulmonary contusion?
Oxygen, ventilate if necessary
What causes a myocardial contusion?
Direct blunt trauma over the praecordium
What investigation findings are consistent with a myocardial contusion?
Abnormal ECG e.g. arrhythmias. Raised trop.
How do you treat a myocardial contusion?
Bed rest, cardiac monitoring, treat arrhythmias
What causes a contained aortic disruption?
Rapid deceleration injury (80% are immediately fatal)
How does a contained aortic disruption present?
Initially stable but becomes hypotensive
What investigations should you do in a suspected contained aortic disruption?
CXR: wide mediastinum, deviation of NGT
CT
Who should you refer to if you suspect a contained aortic disruption?
Cardiothoracics
When should you consider a diaphragmatic injury?
Penetrating injuries below the 5th rib or high energy compression
Which investigations will show a diaphragmatic injury?
CXR (visceral herniation), CT
What causes an oesophageal disruption?
Penetrating trauma
What is the important complication of oesophageal disruption
Mediastinitis
Which investigations will show an oesophageal disruption?
CXR: pneumomediastinum, surgical emphysema
CT
How does tracheobronchial disruption present?
- Persistent pneumothorax
- Pneumomediastinum
How do you treat tracheobronchial disruption?
Thoracotomy
Which mechanisms of abdominal injury need surgical exploration?
Penetrating all need exploration because the tract may be deeper than it looks.
Blunt traumas should still invoke a high index of suspicion for taking the theatre
Which investigations should you consider in an abdominal trauma?
- Urine dip
- FAST scan
- Diagnostic peritoneal lavage
What is the point of doing a urine dip in an abdominal trauma?
Haematuria suggests the renal tract has been damaged
What is the advantage of a FAST scan and what is it replacing?
- Replaces DPL
- Checks for fluid in the abdo, pelvis and pericardium - 90% sensitive for free fluid
- Can be extended to look for pneumothoraces
What are the pros and cons of diagnostic peritoneal lavage in abdominal trauma?
- 98% sensitive for intra abdo haemorrhage
- Useful if can’t do a FAST
- May be better for identifying injury to hollow viscus
- Unable to identify retroperitoneal injury
How do you do a diagnostic peritoneal lavage?
- Insert urinary catheter and NGT (decompression to minimise risk of injury)
- Midline incision through skin and fascia at 1/3 distance from umbilicus to pubic symphysis (arcuate line)
- Carefully dissect to the peritoneum and insert a urinary catheter
- Instil 10ml/kg warmed Hartmann’s
- Drain fluid back into bag and send sample to lab
- Positive = >100,000 RBCs/mm3, bile/intestinal contents
What are the indications for a laparotomy in abdominal trauma?
- Unexplained shock
- Peritonism: rigid silent abdomen
- Evisceration: bowel or omentum
- Radiological evidenc eof intraperitoneal gas
- Radiological evidence of ruptured diaphragm
- Gunshot wounds
- Positive DPL or CT
What are the aims of damage control surgery in abdominal trauma?
- Limit physiological stress
- Controll haemorrhage: ligation and packing
- Control contamination
- Stabilise in ITU
What is Kehr’s sign?
Shoulder tip pain secondary to blood in the peritoneal cavity. Left Kehr sign is a classic symptom of ruptured spleen
How do you classify spleen ruptures?
- Capsular tear
- Tear + parenchymal injury
- Tear up to the hilum
- Complete fracture
How do you manage a ruptured spleen?
- Haemodynamically unstable -> laparotomy
- Stable 1-3: observe in HDU
- Stable 4: consider laparotomy
- Suture the laceration or partial/complete splenectomy
How do you manage liver trauma?
- Conservative if capsule is intact
- Suture laceration
- Partial hepatectomy
- Packing
How do you manage bladder trauma and what normally causes it?
- Assoc with pelvic injuries
- Intraperitoneal rupture needs laparoscopic repair with urethral and suprapubic drainage
- Extraperitoneal rupture can be treated conservatively with urethral drainage
- Give prophylactic antibiotics
How do you classify urethral injuries and what are the mechanisms for them?
- Anterior
- Spongy urethre (penile and bulbar)
- Occur from straddling injuries or instrumentation
- Posterior
- Membranous urethra
- Pelvic fractures
How do urethral injuries present?
- Associated pelvic fracture
- Blood in urethral meatus or scrotum
- Perineal bruising
- High riding prostate
- Inability to micturate and palpable bladder
How do you investigate a suspected urethral injury?
Retrograde urethrogram
How do you manage a urethral injury?
Suprapubic catheter, surgical repair
What is the commonest cause of trauma death?
Head injury (alone or in combination with other injuries) - 50%
What is the difference between a primary and secondary brain injury?
Primary - occurs at the time of injury and is a result of direct or indirect injury to the brain tissue.
Secondary - occurs after the primary injury
What are the types of primary brain injury?
- Diffuse
- Concussion/mild traumatic brain injury
- Diffuse axonal injury
- Focal
- Contusion
- Intracranial haemorrhage
What are the features of concussion?
- Temporary decrease in brain function
- Headache
- Confusion
- Visual symptoms
- Amnesia
- Nausea
What are the features of diffuse axonal injury?
- Shearing forces disrupt axons
- May lead to coma and persistent vegetative state
- Autonomic dysfunction -> fever, hypertension, sweating
What are the features of brain contusions?
Can be coup or contra coup. May have a focal neurological deficit
What are the types of intracranial haemorrhage?
- Extradural
- Subdural
- Subarachnoid
- Parenchymal haemorrhage and laceration
What are the causes of secondary brain injury?
- Hypoxia
- Hypercapnoea
- Hypotension
- Raised ICP
- Infection
Explain the Monroe-Kelly doctrine
The cranium is a rigid box so the volume of its contents must remain constant if ICP is not to change. An increase in the volume of one constituent leads to a compensatory decrease in another (CSF, blood - especially venous). These mechanisms can compensate for a volume change of ~100ml before ICP raises. As autoregulation fails, ICP increases rapidly leading to herniation
What determines cerebral blood flow and cerebral perfusion pressure?
CBF is proportional to CPP x radius of vessels.
CPP = MABP - ICP
What happens to CPP and CBF when ICP increases?
- Raised ICP -> decreased CPP -> decreased CBF
- Autoregulation -> vasodilatation -> increased volume -> increased ICP
What can you do to attenuate the vicious cycle of raised ICP causing reduced CPP and CBF and therefore raising ICP?
- Ventilate to normocapnoea: 4.5kPa
- IV fluid to normovolaemia
- Mannitol bolus acutely
What is the Cushing reflex and what does it mean?
- Hypertension, bradycardia, irregular breathing
- Indicates immediate herniation
How do you classify head injuries by GCS?
- 3-8 = coma
- 9-12 = moderate head injury
- 13-15 = mild head injury
What are the signs of a basal skull fracture?
- CSF rhinorrhoea or otorrhoea
- Battle sign: bruised mastoid
- Panda sign: bilateral orbital bruising
- Haemotympanum
What investigations should you do in a head injury?
- C spine
- Consider CT head
- Bloods: FBC, U+E, glucose, clotting, EtOH level, ABG
What are the indications for doing a CT head in a head injury?
- Basal or other skull fracture
- Amnesia >30 min retrograde (before event)
- Neurological deficit e.g. seizures
- GCS <13 at the scene, or <15 2 hours later
- Vomiting more than once
How do you manage a head injury?
- Neurosurgical consult if positive CT
- Admit if:
- LOC >5 min
- Abnormalities on imaging
- Difficult to assess: alcohol, post ictal
- Not returned to GCS 15 after imaging
- CNS signs: persistent vomiting, severe headache
- NEuro obs half hourly until GCS 15 (GCS, pupils, TPR, BP)
- Analgesia: codeien phosphate 30-60mg PO/IM QDS
- Suture scalp lacs
- Antibiotics if open/base of skull fracture
What are the indications for intubation in a head injury?
- GCS ≤8
- PaO2 <9kPa on air/<13kPa on O2 or PCO2>6kPa
- SPontaneous hyperventilation: PCO2<4kPa
- Respiratory irregularity
How do you treat raised ICP?
- Elevate bed
- Good sedation, analgesia ± NM block
- Neuroprotective ventilation
- Mannitol or hypertonic saline
What discharge advice should you give in head injury?
- Stay with someone for the first 48 hours
- Give advice card telling them to come back if:
- Confusion, drowsiness, unconsciousness, fits
- Visual problems
- Very painful headache that won’t go away
- Vomiting
What are the risk factors for burns?
- Age: children and elderly
- Comorbidities: epilepsy, CVA, dementia, mental illness
- Occupation
How are burns classified?
- Superficial
- Partial thickness
- Full thickness
What are the features of superficial burns?
Erythematous and painful e.g. sunburn
What are the 2 kinds of partial thickness burns and how long do they take to heal?
- Heal in 2-3 weeks if not complicated
- Superficial
- No loss of dermis
- Painful
- Blisters
- Deep
- Loss of dermis but adnexae remain
- Healing from adnexae e.g. follicles
- V painful
What are the features of full thickness burns?
- Complete loss of dermis
- Charred, waxy, white skin
- Anaesthetic
- Heal from the edges leading to a scar
What are the complications of burns?
- Early
- Infection: loss of barrier, necrotic tissue, SIRS
- Hypovolaemia: loss of fluid in skin + increased capillary permeability
- Metabolic disturbance (raised K, raised myoglobin, raised Hb -> AKI)
- Compartment syndrome if circumferential burns
- Peptic ulcers (Curling’s)
- Pulmonary (laryngeal oedema, CO poisoning, ARDS)
- Renal and hepatic impairment
- Intermediate
- VTE
- Pressure sores
- Late
- Scarring
- Contractures
- Psychological problems
What is the Wallace rule?
9s - % body surface area burnt:
- Head and neck = 9%
- Arms = 9% each
- Torso = 18% front and back
- Legs = 18% each
- Perineum = 1%
- Palm = 1%
What are the specific concerns in management of burns?
- Secure airway
- Manage fluid loss
- Prevent infection
What are the signs of CO poisoning?
- Headache
- Nausea + vomiting
- Confusion
- Cherry red appearance
What is the Parkland formula?
To guide fluid replacement in first 24 hours after a burn:
- 4 x weight (kg) x % burn = mL of Hartmann’s in first 24h
- Replace fluid from time of burn
- Give half in the first 8h
- Best guide is UO - aim for 30-50ml/h
What is the Muir and Barclay formula?
To guide fluid replacement in burns:
- (weight x % burn)/2 = ml of colloid per unit time
- Time units: 4, 4, 4, 6, 6, 12 = 36 hours total
- May need to use blood
How do you treat burns?
- Analgesia: morphine
- Dress partial thickenss burns
- Biological, synthetic, cream e.g. flamazine (silver sulfadiazine) + sterile film
- Full thickness burns: tangential excision debridement or split thickness skin grafts
- Circumferential burns may require escharotomy to prevent compartment syndrome
- Anti-tetanus toxoid (0.5ml ATT)
- Consider prophylactic antibiotics espcially anti-pseudomonal
What is the definition of hypothermia?
Core (rectal) temp <35C
How does the body lose heat?
- Radiation: 60%
- Infra red emissions
- Conduction: 15%
- Direct contact
- Primary means in cold water immersion
- Convection: 15%
- Removes warmed air from the body
- Moreso in windy environments
- Evaporation: 10%
- Removal of warmed water
- Moreso in dry, windy environments
How is hypothermia classified aetiologically?
- Primary - environmental exposure
- Secondary: change in temperature set point
- E.g. age related, hypothyroidism, autonomic neuropathy
How is hypothermia classified by severity?
- Mild - 32-35C
- Moderate - 28-32C
- Severe - <28C
What are the features of mild hypothermia?
Shivering, tachycardia, vasoconstriction, apathy
What are the features of moderate hypothermia?
Dysrhythmia, bradycardia, hypotension, J waves, reduced reflexes, dialted pupils, reduced GCS
What are the features of severe hypothermia?
VT->VF->cardiogenic shock
Apnoea, non reactive pupils, coagulopathy, oliguria, pulmonary oedema
Which investigations should be done in hypothermia?
- Rectal/ear temperature
- FBC, U+E, glucose
- TFTs, blood gas
- ECG
- J waves: between QRS and T Wave
- Arrhythmias
How should you manage hypothermia?
- Cardiac monitor
- Warm IVI 0.9% NS
- Urinary catheter
- Consider antibiotics for prevention of pneumonia
- Routine if temp <32 and >65 years
- Slowly rewarm
- Reheating too quickly -> peripheral vasodilatation and shock
- Aim for 0.5C/hour
- Passive external: blankets, warm drinks
- Active external: warm water or warmed air
- Active internal: mediastinal lavage and CPB (severe hypothermia only)
What are the complications associated with hypothermia?
- Arrhythmias
- Pneumonia
- Coagulopathy
- Acute renal failure
