Critical care Flashcards
Admission criteria for ICU (2)
1) Reversible condition
2) Good functional capacity
Scoring systems in ICU (3)
1) APACHE
2) SAPS
3) Mortality prediction model
Levels of care in ICU (0-3)
0 - pt needs met on normal ward
1 - risk of deterioration, support of critical care team
2 - HDU (high dependency unit) - single failing organ support, post-op care
3 - ICU, resp support, support of at least 2 organs
7 indications for sedation
1) Analgesia
2) Anxiety
3) Dyspnoea
4) Mechanical ventilation
5) Facilitate nursing care
6) Decrease oxygen consumption
7) Delirium
5 main drugs used for sedation (& examples of each)
1) Opioids - morphine, fentanyl, femifentanil, alfentanil
2) Benzos - midazolam, lorazepam, diazepam
3) Propofol
4) Haloperidol (dopamine antagonist)
5) Alpha 2 agonists - clonidine, dexmedetomidine
Amnesic & analgesic properties of sedatives
Opioids - analgesic but not amnesic Benzos - amnesic Proprofol - amnesic but not analgesic Haloperidol - amnesic Alpha 2 agonists - amnesic + analgesic
Propofol
Mechanism of action
Effect on resp system
Effect on cardio system
Facilitate GABA transmission
RESP:
1) Resp depression - reduced tidal volume + increased RR
2) CO2 curve to right
CARDIO:
1) Hypotension due to vasodilation, bradycardia, reduced contractility
What is ARDS?
Severity scale
4 Causes
Non-cardiogenic pulmonary oedema - damaged alveoli = leakage of fluid across alveolar capillary membrane
Severity by PaO2/FiO2 ratio (arterial O2 is less than inhaled = failure of lung to transport into blood):
Mild <300
Moderate <200
Severe <100
Causes:
1) Sepsis
2) Pneumonia
3) Trauma
4) Iatrogenic - transfusion, marrow transplant
ARDS
- Sx 5
- diagnostic criteria 3
1) Cyanosis
2) Tachypnoea
3) Tachycardia
4) Peripheral vasodilation
5) Bilateral fine inspiratory crackles
1) acute
2) cxr = bilateral oedema
3) ABG = reduced PaO2/FiO2
ARDS
- management
1) Mechanical ventilation
2) Avoid fluid overload
3) Severe - prone, neuromuscular blockade
What is colonisation?
presence of bacteria without causing infection
What colour do gram-positive & gram-negative bacteria stain?
POSITIVE = PURPLE NEGATIVE = PINK
MRSA is sensitive to (5)
1) Vancomycin
2) Telcoplanin
3) Linezolid
4) Co-trimoxazole
5) Ciprofloxacin
How to remember gram-positive cocci
How to remember gram-positive bacilli
+ COCCI:
strep, staph, Lactococci, Viridans, Enterococci = LOVE
+ BACILLI:
Actinomyces, Bacillus, Clostridium, Connybacterium, Listeria (ABC - cl)
How to remember gram negative cocci
How to remember gram negative bacilli
- COCCI
Neisseria (ne = neg), moraxella - BACILLI
most end in ella (shigella, klebsiella, legionella)
Flew helicopter over camp, got water-borne diarrhoea, went to hospital = helicobacter, campylobacter, e.coli, vibrio, haemophilus, pseudomonas
Abx treatment for c diff
Metronidazole/vancomycin
What 3 main issues occur in post-critical care syndrome?
1) ICU-acquired weakness - breathing, muscle wasting, joint stiffness
2) Brain dysfunction - memory, attention, problem solving
3) Mental health problems - PTSD, insomnia, depression
Mental capacity act
2 stage test
4 ways to confirm capacity
5 principles of MCA
1) Impairment of mind/brain?
2) Does it affect ability to make specific decision?
1) understand
2) retain
3) weigh up
4) communicate decision
1) presume capacity
2) support decision making
3) not lack capacity just because decision unwise
4) best interests
5) least restrictive option
Is an advance statement/advance decision legally binding?
Advance statement - NO
Advance decision - YES, must be in writing, signed & witnessed
What are 5 different reasons for futility & withdrawing treatment?
1) Physiological eg. giving adrenaline to hypotensive patient & no response
2) Benefit-centred
- quantitative: failed in last x times
- qual: QoL below threshold
3) Cost-based
4) Imminent demise - treatment won’t change fact that they will die
5) Lethal condition - won’t be affected by treatment & will die
What 4 drugs are given at end of life
1) Morphine
2) Anti-emetic
3) Hyoscine Butylbromide
4) Midazolam
What is the definition of death?
Irreversible loss of consciousness + irreversible loss of capacity to breathe
How do you diagnose neuro death? (3)
1) Fulfilment of preconditions
- unconscious + apnoeic + mechanical ventilation
- irreversible brain damage of known aetiology
2) Exclusion of reversible contributions to state of apnoeic coma eg. drugs, cord injury, neuromuscular weakness
- nerve stimulator
- period of observation to allow drug elimination
- antagonist administration
- plasma analysis
- cerebral angiography
3) TWICE demonstrate coma, apnoea, absence of brainstem reflex activity
- pupillary constriction (CN 2 & 3)
- blinking (CN 5 & 7)
- eye movement (CN 3,4,6,8)
- response to painful stimuli (CN 5 & 7)
- gag reflex (9 & 10)
- cough reflex (10)
- apnoea test
How do you diagnose cardiac death? (4)
After 5 mins asystole
1) loss of circulation - absence of pulsatile flow on arterial line/echo
2) absence of pupillary reaction
3) motor response to corneal stimulation
4) supra-orbital pressure
What are the 2 types of organ donation & how do their processes differ?
Liver & kidneys have a higher rate of non-function in…
Warm ischaemic time for:
liver
kidney & pancreas
lung
1) After brain stem death
- diagnosis –> optimise –> mobilise team –> retrieval
2) After cardiac death
- mobilise team –> wait for death –> diagnose –> retrieval
Organ donation from circulatory death
<30mins
<60min
<90min
Absolute & relative CI for organ donation
ABSOLUTE
1) not on ventilator
2) >85
3) primary intra-cerebral lymphoma
4) secondary intra-cerebral tumours
5) Active cancer with spread
6) melanoma
7) TB
8) HIV
RELATIVE
1) systemic sepsis
2) hep b/c
3) trauma to organ
What is DIC and why is it a bad sign in shock?
When the body goes into shock the inflammatory markers will often also activate the CLOTTING CASCADE leading to SYSTEMIC PLATELET AGGREGATION and widespread microvascular thrombosis
In DIC all of the products for coagulation are used up in the clots in the microvasculature and this means that there are no more platelets etc. for clotting elsewhere - it therefore presents with microvascular bruising or bleeding and extensive bleeding from surgical sites and wounds - microvascular HAEMOLYTIC ANAEMIA
4 types of shock & examples
1) Hypovolaemic
2) Cardiogenic - MI, arrhythmia
3) Distributive - anaphylaxis, sepsis, neurogenic
4) Obstructive - secondary pump failure due to:
impaired ventricular emptying: PE
impaired ventricular filling: tension pneumothorax
8 Signs of hypovolaemic shock
impact on CO & SVR
treatment (1)
1) pale, cool, clammy
2) syncope
3) weak
4) confused
5) Tachycardia
6) Tachypnoea
7) Low BP
8) Low urine output
9) signs of cause - tender epigastrium, grey turners/cullens. malaena
Low CO
Low SVR
FLUIDS/blood transfusion
10 Signs of cardiogenic shock
Impact on CO & SVR
Treatment (1)
1) pale, cool, clammy
2) chest discomfort
3) syncope
4) JVP
5) pulmonary oedema
6) orthopnoea
7) tachycardia
8) tachypnoea
9) low BP
10) low urine output
Low CO
Increased SVR
Inotrope - Dobutamine
7 Signs of anaphylactic shock
Impact on CO & SVR
Treatment (4)
1) flushed, swollen, itchy
2) low urine output
3) urticaria
4) LOC
5) bronchoconstriction
6) tachycardia
7) low BP
Increase CO
Decrease SVR
500mg adrenaline
fluid challenge
10mg chlorphenamine
200mg hydrocortisone
2 definition of septic shock
8 Signs of septic shock
Impact on CO & SVR
Treatment (1)
1) sepsis + lactate >2
2) sepsis + needing vasopressor to maintain MAP >65
1) pyrexia and rigors (rarely hypothermia)
2) nausea and vomiting
3) rash and menigism
4) warm peripheries, fast cap refill
5) bounding pulse
6) jaundice
7) bleeding dt coagulopathy (eg from vascular puncture sites)
8) confusion and reduced consciousness
Increase CO
Decrease SVR
Vasopressor - Noradrenaline
sepsis criteria temp HR BP RR WBC Mental state glucose urine output o2 sats creatinine bilirubin platelets
>38.3 or <36 >130bpm <90 >24 <4 or >12 altered mental state hyperglycaemia nil for 18h/<0.5 with catheter <91% creatinine >177 bilirubin >34 platelets <100
Signs of obstructive shock
1) Muffled heart signs
2) LOC
3) JVP
4) signs of poor perfusion
NEWS measures 6 things
1) HR
2) BP
3) Temp
4) O2 sats
5) RR
6) ACVPU
2 types of intra-vascular monitoring on ICU
- arterial line (measures BP and can get repeat ABGs from)
- central venous catheter (basically invasive measuring of JVP, can also give drugs like noradrenaline through)
Define + causes
Type 1 resp failure
Type 2 resp failure
Hypoxia (perfusion problem - failure of oxygen exchange)
PaO2 <8
PaCO2 normal/<6
1) cardiogenic pulm oedema
2) pneumonia
3) ARDS
4) asthma
5) lung fibrosis
6) septic shock
7) pneumothorax
8) PE
Hypercarbia - ventilation problem, can’t remove CO2
PaO2 normal/<8
PaCO2 >6
1) COPD
2) chest wall deformities
3) resp muscle weakness eg. gullain barre
4) resp depression from drugs
6 Signs of respiratory distress
1) cyanosis
2) tripod
3) pursed lip breathing
4) accessory muscles
5) unable to speak complete sentences
6) confusion
inspiratory:expiratory ratio
what happens in obstrucive disease
1: 2
1: 3, 1:4 etc, trouble expelling air
when listening to lungs where must you NOT forget to listen to?
AXILLA
How to treat:
type 1 resp failure
type 2 resp failure
TYPE 1
Nasal cannula 2-6L/min or face mask 5-10L/min
TYPE 2
aim 88-92%
Venturi 24% or 28% or Nasal cannula 1-2L/min
What are the patterns of: - FEV1 - FVC - FEV1/FVC ratio in: - normal lungs? - obstructive disease? - restrictive disease?
incl numbers if poss (% predicted and ratio as a decimal)
NORMAL
- FEV1 >80% predicted
- FVC >80% predicted
- FEV1/FVC ratio >0.7
OBSTRUCTIVE - increased airway resistance eg. asthma, COPD
- FEV1 <80% predicted (reduced)
- FVC >80% predicted (may be slightly reduced)
- FEV1/FVC ratio <0.7 (reduced)
RESTRICTIVE - difficulty expanding eg. fibrosis, chest wall disease
- FEV1 <80% predicted (reduced)
- FVC <80% predicted (reduced)
- FEV1/FVC ratio >0.7 (normal)
What are the 5 different types of blood products?
what are each used for?
WHOLE BLOOD
- everything, incl clotting factors and plasma EXCEPT platelets
- rarely used but good for acute large volume bleed
PACKED RED CELLS
- blood without the plasma
- treating symptomatic anaemic and major acute blood loss (if give >4 units, give platelets too to ensure stability)
PLATELET CONCENTRATES
- just platelets
- used to correct a low platelet count or before a procedure if bleeding is a big risk
FRESH FROZEN PLASMA (FFP)
- plasma, incl clotting factors
- used for :
- – emergency reversal of warfarin
- – massive haemmorhage
- – intracranial bleed
- – DIC (to replace consumed clotting factors)
- – liver failure with bleeding
CRYPRECIPITATE
- specific clotting factors are centrifuged out of FFP
- used to treat specific deficit conditions - haemophilia, vWD, low fibrinogen levels, DIC
How much is 1 unit of blood?
around 500ml
Complications of blood transfusion:
- immediate? 4
- delayed? 5
IMMEDIATE:
1) Urticaria
2) Febrile non-haemolytic reaction
- Sometimes there is an acute rise in body temperature when the blood is first run through
3) Dilution coagulopathy
- After giving too much packed red cells you can dilute the clotting factors to the point where the person is at a bleeding risk (This is why you give FFP after 4 units of packed red cells)
4) Hyperkalaemia
- Potassium is released during haemolysis and there will be some degree of breaking down of red blood cells in the bag and this will leak into the patient leading to elevated levels of potassium
5) Hypocalcaemia
DELAYED:
1) Delayed haemolytic transfusion reaction
2) Graft versus host disease
3) Immunosuppression
4) Viral infection
5) Iron overload = hemochromatosis
