Critical Care Flashcards
(49 cards)
What are the levels of care?
0 = needs can be met through normal ward
1 = at risk of condition deteriorating - advice and support from critical care
2 (HDU) = More detailed observation (hourly) or intervention - single organ support (more than 50% O2, NIV, vasoactive drug infusions, post-op care.
3 (ICU) = advanced respiratory support alone or multiple organ failure. Haemodialysis = level 3 due to intensity involved in maintaining it.
Components of NEWS?
RR O2 sats Supplmenetal oxygen Temp Systolic BP HR Level of consciousness
What are low, medium and high NEWS scores and what do they mean?
0 = 12 hourly monitoring minimum
1-4 = low = minimum 4 hourly obs
5 (or 3 in one parameter) = medium = minimum 2 hourly obs
7+ = high = minimum 1 hourly obs
Causes of hypovolaemic shock?
Blood loss - trauma, GI bleed, ruptured AAA/ectopic
Fluid loss/redistribution - burns, GI losses, pancreatitis, sepsis
Presentation and physiological response to hypovolamic shock?
Cool and pale
Reuduced CO –> increased SVR
Causes of distributive shock?
Sepsis, anaphylaxis, neurogenic, liver failure, adrenal insufficiency, drugs and toxic exposures
Presentation and physiological response to distributive shock?
Warm and vasodilated
Low SVR –> Increased CO
Causes of cardiogenic shock?
Primary = MI, arrhythmias, valve dysfunction, myocarditis
Secondary = tamponade, massive PE, tension pneumothorax
Presentation and physiological response to cardiogenic shock?
Cool and pale
Low CO –> increased SVR
What are clinical signs of shock?
General = systolic BP <90, lactate >3, increased CRT, increased BE
Brain = lethargy, somnolence
Kidneys = oliguria/anuria (only directly measurable indicator of organ function)
Attempted compensation = tachycardia, tachypnoea
What are haemodynamic goals in cardiovacular failure?
MAP >65 mmHg (or higher if usually hypertensive)
Urine output > 0.5 ml/kg/hr
CVP 8-12 mmHg
How to calculate the MAP?
Diastolic pressure + one third of the pulse pressure
Systemic goals in cardiovascular failure?
Optimise oxygen delivery to tissues…
Central venous oxygen saturation >70%
Normalise lactate
Ensure adequate ventilation/breathing
Receptors that inotropes work on?
Adrenaline = b > a Noradrenaline = a > b Dopamine = DA > b > a Dobutamine = b1 and b2
Clinical features of hypoxia?
Dyspnoea; restlessness; agitation; confusion; central cyanosis.
If long-standing hypoxia: polycythaemia; pulmonary hypertension; cor pulmonale.
Clinical features of hypercapnia?
Headache; peripheral vasodilatation; tachycardia; bounding pulse; tremor/flap; papilledema; confusion; drowsiness; coma.
Bounding pulse because CO2 causes reduced SVR –> increased HR
Investigations in respiratory failure?
Aimed at identifying underlying cause.
Bloods – FBC; U&E; CRP; ABG.
CXR
Microbiology; sputum and blood cultures (if febrile)
Spirometry (COPD, neuromuscular disease, Guillain-Barré syndrome).
Definition of type 1 respiratory failure?
Hypoxaemia without hypercapnia
pO2 < 8 kPa ON AIR
pCO2 < 6.0 kPa
Able to blow off the CO2
Causes of type 1 respiratory failure?
V/Q mismatch (Pneumonia, pulmonary oedema, PE, asthma, emphysema, pulmonary fibrosis, ARDS)
Upper airway obstruction
Low oxygen in inspired air
Management of type 1 respiratory failure?
Treatment of the underlying cause
Treatment of the hypoxia
• Start high and reduce later when proven patient does not need it.
If still PaO2 < 8kPa despite maximal oxygen therapy (60%) –> HDU/ICU and CPAP.
Definition of type 2 respiratory failure?
Hypoxaemia with hypercapnia
pO2 < 8 kPa ON AIR
pCO2 > 6.0 kPa
Not able to blow off the CO2
Causes of type 2 respiratory failure?
Hypoventilation or Increased dead space
Pulmonary disease
• Asthma, COPD, pneumonia, end-stage pulmonary fibrosis, obstructive sleep apnoea.
Reduced respiratory drive
• Sedative drugs, CNS tumour or trauma.
Neuromuscular disease
• Cervical cord lesion, diaphragmatic paralysis, poliomyelitis, myasthenia gravis, Guillain-Barré syndrome.
Thoracic wall disease
• Flail chest, kyphoscoliosis
Management of type 2 respiratory failure?
Treat underlying cause
Controlled oxygen therapy – start at 24% - recheck ABG after 20 mins –> if PaCO2 is steady or lower, increase O2 concentration to 28%. If PaCO2 has risen or patient still hypoxic, consider NIV.
Last resort, intubation and ventilation if appropriate.
What is ARDS?
May be caused by direct lung injury or occur secondary to systemic illness. Lung damage and release of inflammatory mediators cause increased capillary permeability and pulmonary oedema, often accompanied by muti-organ failure.