Exam Prep Flashcards
Outline the RASS score levels.
0 - Alert and calm
+1 - Restless, anxious but not aggressive or interfering with assessment.
2+ - Agitated w/ frequent non-purposeful interference to assessment not aggressive to others.
3+ - Very agitated. Pulls or removes interventions (tubes, IV, catheters), aggressive to self.
4+ - Combative, violent towards others.
What drugs and doses are given for each RASS score?
RASS 0 - Nil
RASS 1 - 2: 10mg Olanzapine (2x 5mg wafers). Repeat once only after 15 mins if indicated to total maximum cumulative dose via all routes 20mg/24hrs.
RASS 1-3: Droperidol IM 5-10mg / IV 2.5-5mg. Repeat after 15mins if indicated to a total maximum cumulative dose via all routes 20mg/24hrs.
RASS 4: Ketamine 4mg/kg (max 400mg). IV maintenance 0.5mg/kg every 5 mins.
What are the six Rs of medication?
Right:
- Patient
- Medication
- Dose
- Route
- Time/interval
- Documentation
What is the target oxygen saturations for a COPD patient?
88% - 92%
True or False: Males are twice as likely to sustain brain injuries.
True
What are the leading causes of death in the first year post brain injury?
- Seizures,
- Septicaemia,
- Pneumonia,
- Digestive complications.
With regard to head injuries what GCS levels are associated with Mild, Moderate and Severe?
Mild - GCS 14-15
Moderate - GCS 9-13
Severe - GCS 3-8
Focal and diffuse injuries can be associated with head injuries. What are they?
Focal: scalp lacerations, skull fractures, surface contusions.
Diffuse: Diffuse axonal injuries, hypoxic/ischaemic damage and vascular injuries.
What percentages of body mass, oxygen, glucose and cardiac output is the brain responsible for?
2% body mass
20% oxygen
25% glucose
15% cardiac output
Constant cerebral blood flow is maintained by____?
- Ensuring an adequate pressure (cerebral perfusion pressure) to force blood into the head; and
- A regulatory mechanism (autoregulation), which ensures a constant blood flow by varying
the resistance to blood flow as the perfusion pressure changes.
How do you calculate the Mean Arterial Pressure (MAP)?
Pulse Pressure = Systolic pressure – Diastolic pressure
MAP = diastolic pressure + 1/3 pulse pressure
Define cerebral perfusion pressure (CPP).
CPP is the amount of pressure required to push blood through the cerebral circulation, therefore maintaining blood flow, oxygen and glucose delivery to brain cells and is directly related to the amount of intracranial pressure.
How do you calculate cerebral perfusion pressure (CPP)?
CPP = MAP - ICP
What are the normal ranges for MAP, ICP and CPP?
MAP = 85 – 95mmHg
ICP <15mmHg
CPP = 70 - 80mmHg
Define a traumatic brain injury.
A traumatic insult to the brain capable of producing physical, intellectual, emotional, social, and vocational change.
Traumatic brain injuries can be divided into 2 categories. What are they?
Primary: As a result of the injury.
Secondary: Complex cellular and metabolic injuries that occur after the primary injury.
There are internal and external causes for secondary traumatic brain injuries. What are they?
Internal: Herniation, ischemia, cerebral oedema, hematomas, intracranial hypertensions.
External: Hypotension, hypoxia, anemia, hyper/hypoglycemia, hyper/hypocapnia, seizures.
What is the Monro-kellie hypothesis?
When one compartment expands, another should reduce its volume or ICP will increase.
What is Cushing’s Triad and when is it seen?
Hypertension
Bradycardia
Irregular breathing
Seen in late stages of very high ICP.
What are the two types of posturing associated with head injuries?
Decorticate (inwards):
Rigid flexion of the arms, twisting towards the centre of the body with clenched fists. Suggestive of damage to the neural pathways between the brain and spinal cord typically above the level of the brainstem.
Decerebrate (outward):
Stiffening of arms and legs away from the centre of the body w/ an arched back, pointed toes and out stretched fingers. Suggestive of damage to the brainstem, particularly within or below the upper midbrain.
What are the signs of elevated ICP in a decompensated state?
- Altered GCS
- Headache
- Vomiting
- Papilledema (swelling of the optic disc)
- Pupillary changes
- Cushing’s triad
- Seizures
- Visual changes
- Neck stiffness and pain
- Changes in speech
What is the trauma management general principals?
- Initial scene assessment – backup required?
- Control catastrophic hemorrhage – extreme bleeding that can lead to
death within minutes. Early TPOD/C.A.T - A – E assessment – consider C-spine and immediately manually immobilize.
- Airway and ventilatory support as required
- Other hemorrhage control
- IV access – consider fluids if hypotensive 20mls/kg Max 2L in 250ml bolus
and reassess perfusion. Make sure you consider what is occurring though
and the potential need for permissive hypotension - Cardiac Monitor
- Maintain temperature
- Secondary and CNS surveys where appropriate
- Consider analgesia- Major trauma first line Fentanyl and consider the need
for secondary Ketamine (Cautious with concurrent use) - Fracture immobilisation
- Consider anti-emetic (Prophylaxis Ondanseteron)
- If time critical/major trauma, minimise on scene time - < 10 mins if possible
What are the 4 classifications of musculoskeletal injuries?
- Fractures
- Sprains
- Strains
- Joint dislocations
What are possible complications associated with musculoskeletal injuries?
– Hemorrhage
– Instability
– Loss of tissue
– Simple laceration and contamination
– Interruption of blood supply
– Nerve damage
– Long-term disability
Musculoskeletal injuries can result from___?
- Direct trauma:
Blunt force applied to extremity - Indirect trauma:
Vertical fall that produces spinal fracture distant from site of impact - Pathological conditions Forms of arthritis & Malignancy
Fractures of long bones may result in
moderate to severe haemorrhage within first
____ hours?
2
How many mls may be release from fractures to the following bones:
- Tibia or Fibular
- Femur
- Pelvis
Tibia/Fibular: 550ml
Femur: 1000ml
Pelvis: 2000ml
Define a joint dislocation.
When normal articulating ends of two
or more bones are displaced.
Complete joint dislocation is called _____. Incomplete dislocation is called _____.
Complete = luxation
Incomplete = subluxation
What are the 6 Ps when evaluating musculoskeletal injuries?
- Pain
- Pallor
- Paraesthesia
- Pulses
- Paralysis
- Pressure
What are we trying to achieve when splinting a fracture?
- Immobilisation
- Helps alleviate pain
- Decreases tissue injury, bleeding and contamination of open wounds
- Simplifies and facilitates transporting patient
What is the general management principals of fractures?
- Primary Survey
- Consider pain relief early
- A to E assessment
- Manual immobilisation whilst assessing (if possible)
- O2 if indicated
- IV access
- Thorough assessment of injury (6 P’s)
- Splint appropriately
- Apply ice and elevate if appropriate
- Reassess vital signs and 6 P’s
- Transport to appropriate facility (trauma centre)
List 5 cardiovascular conditions.
– Acute coronary syndromes (ACS)
– Atherosclerosis
– Angina pectoris
– Myocardial infarction
– Left ventricular failure and pulmonary oedema
– Right ventricular failure
– Cardiac tamponade
– Aortic aneurysm
– Pericarditis and Endocarditis
Define hypoglycaemia.
Very low blood sugar, usually due to excessive
insulin or insufficient food (also known as insulin
shock). <4mmol/L
Define shock.
The inability of the circulating blood to adequately perfuse the tissues of the body.
Define perfusion.
The ability of the body to adequately circulate blood and provide oxygen to cells.
Define hypoperfusion.
Any malfunction that causes a decrease in cellular oxygenation.
To achieve adequate perfusion, what 3 components of the
cardiovascular system must work properly?
Heart: Must sufficiently pump fluid.
Vasculature: Must maintain integrity and enable blood flow.
Lungs: Must adequately on/off load oxygen.
Define cardiac output.
The amount of blood pumped by the ventricles
in one minute. It is a crucial determinant of organ perfusion.
What are the determining factors of cardiac output?
- Strength of contraction
- Rate of contraction
- Preload: Volume of venous return to the ventricles
Define preload with regard to cardiac output.
The volume of venous return to the ventricles, it is the end-diastolic volume.
How do you calculate cardiac output?
Cardiac output (CO) = Heart rate (HR) × Stroke volume (SV)
- eg: CO = 80 (bpm) × 100 (ml) = 8000 ml/min
What is Starlings Law?
A principle that explains how the heart adjusts its pumping strength in response to blood volume changes.
- Greater preload = greater contraction strength.
- Optimal stretching of cardiac muscles will result in greater contractions.
- Blood input and output should be equal.
Define afterload.
The total resistance against which blood must be pumped to be pumped out to the body. This is directly affected by total peripheral vascular resistance.
Define Mean Arterial Pressure (MAP).
The mean value of theblood pressure in the arterial portion of the circulation.
It represents the average pressure of the vasculature system that perfuses the cells of the body.
How do you calculate pulse pressure?
Pulse Pressure= systolic -diastolic.
What are the 3 stages of shock?
– Compensated shock: there is some decreased
blood flow and perfusion to tissues.
– Decompensated shock: compensatory mechanisms fail and SBP can no longer be maintained.
– Irreversible shock: there is cellular ischaemia and
necrosis and subsequent organ failure.
During the compensatory stage of shock why does the respiratory rate increase?
Respiratory rate often increases in response to increases in acid loading.
What are the signs and symptoms associated with compensated shock?
– CNS: alteration in conscious state, lethargy, confusion, combativeness
– Skin: pale, and cool
– Cardio: elevation of heart rate and increase in systolic pressure
What occurs during decompensated shock?
Compensatory mechanisms fail, pre-capillary sphincters open
and post-capillary sphincters remain closed, causing:
– peripheral pooling of blood,
– capillary engorgement & plasma leakage
– decreases in systolic BP, but diastolic BP maintenance=
narrowing pulse pressure
– decreased myocardial contractility due to ischaemic injury
– dysrhythmias
– acidosis
– rouleaux formations, capillary obstruction & hypercoagulability
– electrolyte imbalances such hyperkalaemia
– heart rate increases
What occurs during irreversible shock?
- Shock progresses and becomes resistant to treatment
- Post-capillary sphincters open allowing toxic by-products to enter the systemic circulation
- There is profound acidosis organ failure
- Widespread vasodilation= massive decreases in systolic diastolic BP
- Tissue necrosis, causes:
– inflammatory changes
– disseminated intravascular coagulation
– multiple organ death
What are the clinical signs of irreversible shock?
– Bradycardia
– Serious dysrhythmias
– Frank hypotension
– Evidence of multiple organ failure
– Pale, cold, clammy skin
* Cardiopulmonary collapse is usually imminent
What are the 5 types of shock?
- Hypovolaemic
- Cardiogenic
- Neurogenic
- Anaphylactic
- Septic
Define hypovolemic shock and outline the causes.
Shock that occurs as
the result of fluid loss.
Causes:
* Haemorrhage
* Burns
* Severe or prolonged diarrhoea
* Vomiting
* Endocrine disorders
* Internal third space losses- such as in peritonitis
Define cardiogenic shock and outline the causes.
Shock that occurs due to
the inability of the heart (cardiac pump) to deliver
adequate circulating blood volume for tissue perfusion.
Causes:
* Inadequate filling of the heart
* Poor contractility of the heart
* Obstruction of blood flow from heart to the central
circulation
Associated conditions:
* Acute MI
* Serious cardiac rhythm disturbance
* Cardiac tamponade
* Tension pneumothorax
* Cardiac contusion
* Severe valvular heart disease
* Cardiomyopathy
* Pulmonary embolism
* Dissecting aortic aneurysm
Define neurogenic shock and outline the causes.
