ICM Flashcards
Define ICU acquired weakness
Clinically detectable weakness in a critically ill patient with no other plausible cause
List the classes of ICU acquired weakness
- Critical illness polyneuropathy
- Critical illness myopathy (histologically classified to cachectic, thick filament and necrotising myopathies)
- Critical illness neuromyopathy
List the risk factors for the development of ICU acquired weakness
- Female
- Increasing age
- Sepsis
- Multi-organ failure
- Drug induced encephalopathy
- Increased duration of acute illness
- Increased duration of mechanical ventilation
- Requirement for parenteral nutrition
- Hypoalbuminaemia
- Hyperglycaemia
- High dose steroids
- Neuromuscular blocking agents
- Vasopressors
List the clinical features of ICU acquired weakness
- Weakness develops after ICU admission
- Generalised symmetrical weakness
- Sparing of facial muscles, cranial nerves and extra-ocular munscles
- Preserved autonomic function
- Difficulties weaning from ventilatory support
- Reduced reflexes
- Normal conscious level
- MRC power score <48/60 (6 muscle groups: shoulder abductors, elbow flexors, wrist extensors, hip flexors, knee extensors, foot dorsiflexors)
List investigations that aid the diagnosis of ICU acquired weakness
- Creatine kinase
- Nerve conduction studies
- EMG
- Muscle biopsy
What proportion of patients diagnosed with ICU acquired weakness will die during their hospital admission?
45%
What proportion of patients with ICU acquired weakness who survive hospital admission will achieve complete recovery?
68%
Indications for neuromuscular block in critically ill patients
- Tracheal intubation
- ARDS
- COVID-19
- Proning
- Abdominal compartment syndrome
- Transfers
Why is lean body weight used for roc?
Hydrophillic, so remains in central compartment
Give the diagnostic criteria for DKA
pH <7.3 and/or bicarb <15mmol/L
Ketones >3mmol/l or ketonuria ++
Capillary glucose > 11mmol/L or known diabetic
Give the two components of initial insulin management of a known diabetic adult patient admitted with DKA
- Start fixed rate insulin infusion at 0/1units/kg/hr
- Continue patient’s regular long acting insulin
State the immediate fluid management of an adult patient admitted with DKA with systolic blood pressure <90mmHg
500mls 0.9% NaCl over 10-15mins
State the equation for calculation of anion gap
(Na+K)-(Cl+Bicarb)
List the biochemical findings of severe DKA in an adult that may warrant HDU referral
- pH < 7.1
- Ketones > 6mmol/L
- Bicarb < 5mmol/L
- K < 3.5mmol/l on admission
- Anion gap > 16
List clinical findings of severe DKA that may warrant a referral to HDU
- GCS < 12
- Systolic < 90mmHg
- HR >100 or < 60bpm
- SpO2 < 92%
Give the patient groups or comorbidities that may indicate need for HDU referral of a patient with DKA
- Young adults 18-25 yrs old
- Elderly
- Pregnancy
- Significant comorbidity e.g. heart failure or renal failure
Give the complications of DKA management
- Hypo/hyperkalaemia with or without cardiac arrhythmia
- Hypoglycaemia
- Cerebral oedema
- AKI
- VTE
List the respiratory symptoms of pulmonary embolism
- Pleuritic chest pain
- Breathlessness
- Haemoptysis
List the signs of pulmonary embolism
- Type 1 respiratory failure/low SpO2/cyanosis
- Pleural rub
- Tachypnoea/increased work of breathing
List the neurological features of pulmonary embolism
- Syncope/presyncope
- Anxiety/apprehension
Give the ECG changes that may be associated with pulmonary embolism
- Tachycardia
- Atrial fibrillation
- Right ventricular strain - S1Q3T3, TWI V1-V4, QR pattern V1
- Pulseless electrical activity
List the clinical presentations which indicate diagnosis of “high risk” pulmonary embolism
- Cardiac arrest
- Obstructive shock (persistent hypotension in association with end-organ hypoperfusion)
Give the tests which may be used to confirm the diagnosis in a patient suspected of having high-risk PE
- CTPA
- V/Q scan
- ECHO (listed second in the textbook but does not confirm diagnosis)
List the contraindications for pharmacological thrombolytic treatment for patients with high risk pulmonary thromboembolism
- History of haemorrhagic stroke or stroke of unknown cause
- Ischaemic stroke within 6 months prior
- CNS neoplasm
- Major traum, surgery or head injury in 3 weeks prior
- Bleeding diathesis
- Active bleeding
Give two interventional or surgical management options for treatment of high risk PE
- Percutaneous catheter directed therapy
- Surgical embolectomy
Give risks to a patient with high risk PE if intubation is required as part of management
- Hypotension, negative inotropic effects of induction agents pre-existing haemodynamic compromise
- Impaired venous return and so reduced right heart output due to positive pressure ventilation
State the mechanism of action for therapeutic effect of TCA
Inhibits reuptake of serotonin and noradrenaline into presynaptic terminals, so raises their concentration for postsynaptic receptor activation
List three additional receptor actions of TCAs and their clinical effect
- Sodium channel antagonism - cardiac depression
- Alpha adrenergic antagonism - hypotension
- Anticholinergic - pupil dilation, tachycardia, hypotension, ileus, irritability, confusion, seizures, coma, urinary retention, pyrexia
What therapeutic interventions an be considered in the management of TCA within 1 hour of ingestion
- Activated charcoal
- Gastric lavage (airway must be protected by pt or you)
List indications for intubation for patients after TCA overdose
- Reduction in GCS that compromises airway protection
- Hypoventilation contributing to acidosis
- Refractory seizures
Treatments that can be used in the management of hypotension and arrhythmia in presence of TCA overdose
- Fluid resuscitation
- 8.4% sodium bicarbonate
- Alpha agonist e.g. adrenaline infusion
- Magnesium sulphate (for dysrhythmia)
- IV glucagon
Apart from tachycardia, give ECG changes seen in TCA overdose
- QRS prolongation
- QTc prolongation
- Nodal or ventricular arrythmia
- R/S ratio > 0.7 in aVR
Give one drug that should be avoided for management of seizures in TCA overdose and what you would use instead
Avoid phenytoin (can lead to phenytoin toxicity with ventricular arrythmias)
Use benzodiazepine
List perioperative risk factors for the development of acute kidney injury
- Hypovolaemia (dehydration, bleeding)
- Hypotension (heart failure, dehydration)
- Locally impaired renal circulation (ACEI, NSAIDS, abdominal compartment syndrome)
- Systemic inflammation (sepsis)
- Nephrotoxins (aminoglycosides, rhabdomyolysis)
- Renal obstruction (renal calculi, misplaced stent)
List patient risk factors for development of AKI perioperatively
- Increasing age
- Male
- CKD
- Chronic liver disease
- CCF
- Hypertension
- Diabetes
List the indications for renal replacement in ICU
- Fluid overload not controlled with medical management
- Hyperkalaemia due to AKI not controlled with medical management
- Metabolic acidosis
- Symptomatic uraemia (encephalopathy, pericarditis) due to AKI
- Overdose with dialysable drug or toxin
- Management of pre-existing CKD in a patient requiring ICU admission
List the types of RRT available on intensive care
- Intermittent haemodialysis
- Contineous renal replacement therapy e.g. CVVHF, CVVHD, CVVHDF
- Peritoneal dialysis (in patients already using this form)
Give possible complications associated with the use of heparin for systemic anticoagulation for maintenance of the RRT circuit
- Heparin-induced thrombocytopenia
- Increased risk of haemorrhage
- Heparin resistance (Reduced antithrombin III production in critically ill patients)
Give complications associated with the use of citrate for regional anticoagulation for maintenance RRT circuit
- Alkalosis (citrate converts to bicarbonate)
- Acidosis (accumulation of citrate)
- Hypocalcaemia (citrate binds to calcium)
- Hypomagnesemia (citrate-calcium complex binding and removal in effluent)
What are the clinical features of propofol infusion syndrome?
- Metabolic acidosis
- ECG changes
- Rhabdomyolysis
- AKI
- Hyperkalaemia
- Lipidaemia
- Cardiac failure
- Pyrexia
- Elevated liver enzymes/hepatomegaly
- Elevated lactate
List risk factors for the development of propofol infusion syndrome
- Low carbohydrate supply
- Higher cumulative propofol dose
- Traumatic brain injury
- Increased severity of critical illness
- High levels catecholamines
- High levels glucocorticoids
- Young age
- Genetic mitochondrial defects
List laboratory findings in propofol infusion syndrome
- Raised CK
- Raised lactate
- High potassium
- High creatinine
- High transaminases
- High triglycerides
How do you minmise the risk of development of propofol infusion syndrome
- Multimodal sedation
- Adequate carbohydrate supply
- Monitor markers
- Avoid in patients with mitochondrial disorders
How do you manage propofol infusion syndrome
- Stop propofol infusion and start alternate sedating agent
- Administer dextrose infusion
- Manage hyperkalaemia
- Fluid resuscitation for hypotension and raised lactate
- Ventilatory management to compensate for metabolic acidosis
Define ICU-acquired weakness
New episode of clinically detected symmetrical, peripheral weakness in a critically ill patient without any other plausible aetiology
What are the three types of ICU-acquired weakness?
- Critical illness polyneuropathy
- Critical illness myopathy
- Critical illness neuromyopathy
What are the risk factors for the development of ICU-acquired weakness?
- Multiorgan failure
- Prolonged immobility
- Hyperglycaemia
- Severe SIRS
- Glucocorticoids
- Electrolyte imbalance
- High lactate
- Parenteral nutrition
- Inappropriate vasoactive drug use
- Abnormal calcium concentration
What patient characteristics are associated with increased risk of ICU-acquired weakness
- Female
- Increasing age
List the features that contribute to the clinical diagnosis of ICU-acquired weakness
- Low muscle strength as assessed by MRC power grading
- Development of weakness occurs after onset of critical illness
- Generalised, symmetrical, flaccid weakness
- Peripheral weakness, spares cranial nerves
- No autonomic involvement
- Other causes excluded
What neurophysiological tests can be used to determine the type of ICU-acquired weakness
- Nerve conduction studies
- Electromyographic studues
- Electrophysiological studies comparing nerve stimulated and muscle stimulated action potentials
List two aspects of ICU care that may reduced development of ICU-acquired weakness
- Early physiotherapy and mobilisation
- Reduction in ventilator dependent days to facilitate weaning
- Optimisation of nutrition
- Close management of blood glucose
- Early cessation of neuromuscular blockade during ventilation
What are the differences between dialysis and filtration?
Define the term ventilator associated pneumonia
Nosocomial lung infection occuring more than 48 hours after starting invasive ventilation
List clinical and investigational fiindings that may indicate presence of VAP
Clinical
* Purulent secretions
* Increasing ventilatory requirements
* Pyrexia
Investigational
* Raised WCC
* Infiltrates on CXR
* Positive sputum cultures