12. Resuscitation in special circumstances Flashcards
1
Q
What is the definition of hyperkalaemia and severe hyperkalaemia?
A
- Hyperkalaemia is defined as K >5.5 mmol/L
- Severe hyperkalaemia is defined as K >6.5 mmol/L
2
Q
What are the causes of hyperkalaemia?
A
- Renal failure
- Drugs
- Tissue breakdown
- Metabolic acidosis
- Endocrine disorders
- Diet
- Spurious (e.g. pseudo-hyperkalaemia)
3
Q
What ECG changes are associated with hyperkalaemia?
A
- First-degree heart block (PR >2s)
- Flattened or absent P waves
- Tall, tented T waves
- ST-depression
- S & T wave merging,
4
Q
What are the principles of hyperkalaemia treatment?
A
- cardiac protection
- shifting K into cells
- removing K from the body
- monitoring serum K and glucose
- preventing recurrence
5
Q
What are the main risks associated with hyperkalaemia?
A
- Hypoglycaemia due to insulin-glucose
- Tissue necrosis secondary to extravasation of IV Ca
- Rebound hyperkalaemia following effects of drug wears off
6
Q
How is mild hyperkalaemia (5.5-5.9 mmol/L) treated?
A
- Correct cause of hyperkalaemia and avoid further elevation
- Potassium binders to remove K from the body
7
Q
How is moderate hyperkalaemia (6.0-6.4) treated?
A
- Insulin-glucose (10 units short acting insulin with 25g glucose IV over 15-30mins)
- Remove K from the body using K chelators or dialysis
8
Q
How is severe hyperkalaemia (>6.5) without ECG changes treated?
A
- Seek expert advice
- Insulin-glucose
- Salbutamol 10-20mg nebulised
- K chelators or dialysis
- Commence continuous cardiac monitoring
9
Q
How is severe hyperkalaemia (>6.5) with ECG changes managed?
A
- Seek expert advice
- Calcium chloride/gluconate for cardiac protection
- Insulin-glucose or salbutamol
- Consider dialysis at outset to remove K
- Continuous cardiac monitoring
10
Q
What are the causes of hypokalaemia?
A
- gastrointestinal loss
- drugs
- renal loss
- endocrine disorders
- metabolic alkalosis
- magnesium depletion
- poor dietary intake
11
Q
What ECG changes are associated with hypokalaemia?
A
- U waves
- T wave flattening
- ST-segment changes
- arrhythmias
12
Q
What is generally considered the maximum safe rate of K infusion?
A
20mmol/hr
13
Q
What are some causes and treatments for other types of electrolyte disorders?
A
14
Q
What are general therapies that may be used in cases of poisoning?
A
- Acivated charcoal - may be effective against certain types of poisoning
- Whole bowel irrigation - effective against sustained-release enteric coated drugs, oral iron poisoning and ingested drug packets
- Urine alkalinisation - effective in mild cases of salicylate poisoning
- Haemodialysis - effective for drugs and metabolites with low molecular weight
15
Q
What specific treatment is given for opioid poisoning and at what doses?
A
- Naloxone
- Initial dose 400mcg IV, 800mcg IM/SC, 2mg IN
- Can be titrated up to max dose of 10mg in severe opioid toxicity
16
Q
When may flumazenil be used for benzodiazepine toxicity?
A
When there is no risk or history of seizures
17
Q
What specific treatments may be considered for severe tricyclic antidepressant toxicity?
A
- Sodium bicarbonate
- Aim for pH target of 7.45-7.55
18
Q
What specific treatments can be given for local anaesthetic toxicity and at what dose?
A
- Lipid emulsion
- 1.5mL/kg 20% bolus for up to 3 doses
- 15mL/kg/hr infusion
- Max dose 12mL/kg
19
Q
What specific treatments can be used for stimulant (e.g. cocaine, amphetamine) toxicity?
A
- Small doses of IV benzodiazepines
- GTN/phentolamine for cocaine-induced coronary vasospasms
20
Q
What are the feaatures of severe asthma?
A
- History of near-fatal asthma attacks
- Hospitalisation or emergency care for asthma in past year
- requiring 3 or more classes of asthma medication
- adverse behavioural/psychologial factors
21
Q
What are the features of asthma attacks of varying severity?
A
22
Q
What are the causes of cardiac arrest in severe asthma?
A
- Severe bronchospasms and mucous plugging causing asphyxia
- Cardiac arrhythmias caused by hypoxia, stimulant drugs or electrolyte imbalance
- Dynamic hyperinflation during mechanical ventilation
- Tension pneumothorax
23
Q
What are the treatments for severe asthma?
A
- Salbutamol 5mg nebulised every 15-30mins
- Nebulised ipratropium (500mcg 4-6hrly)
- Steroids (prednsolone PO or hydrocortisone IV)
- Magnesium sulfate 2g over 20mins
- Aminophylline 5mg/kg IV loading, followied by infusion of 500-700mcg/kg/hr, maintain plasma theophylline level <20mcg/mL
24
Q
When should tracheal intubation be considered in severe asthma?
A
- Despite pharmacological intervention, there is:
1. deteriorating peak flow
2. decreasing conscious level
3. persisting/worsening hypoxia
4. deteriorating respiratory acidosis
5. severe agitation leading to poor complicance with oxygen mask
6. progressive exhausion
7. respiratory/cardiac arrest - Raised PCO2 alone is not an indication for tracheal intubation
25
What modifications to ALS may be required in asthma?
* Ventilation may cause dynamic hyperinflation of lungs. If this is the case, compression of chest wall with period of apnoea may be useful
* Dynamic hyperinflation may increase thoracic impedence and so require greater shock energy
26
What criteria are required for diagnosis of anaphylaxis?
1. Sudden onset ad rapid progression of symptoms
2. Life-threatening airway and/or breathing and/or circulatory problems
3. Skin andor mucosal changes (flushing, urticaria, angioedema)
27
What is the algorithm for initial management of anaphylaxis?
28
When should samples of mast cell tryptase be taken in suspected anaphylaxis?
* Minimum - one sample within 2hrs of reaction onset
* Ideally - 3 timed samples:
1. Sample 1 - as soon as possible
2. Sample 2 - 1-2hrs after symptom onset
3. Sample 3 - 24hrs after symptom onset
29
What is the algorithm for managing refractory anaphylaxis?
30
What modifications to CPR should be made in pregnant patients?
* Left-lateral displacement of uterus to the left to minimise IVC compression, ideally using left lateral tilt
* Ideally, obtain venous access above diaphragm
* Prepare for emergency c-section early
* Consider early tracheal intubation as risk of aspiration is high in pregnancy
31
What are the principles governing emergency c-section according to gestational age?
* <20 wkGA - Emergency c-section should not be considered as uterus unlikely to compress IVC
* 20-23 wkGA - Initiate emergency c-section to allow resuscitiation of mother, fetus unlikely to survive
* >24wkGA - Initiate emergency c-section and try to save both fetus and mother
32
What dose of TXA can be used for traumatic haemorrhage?
Loading dose 1g over 10mins followed by infusion 1g/8hrs
33
What are clinical signs of tension pneumothorax?
* Respiratory distress or hypoxia
* Haemodynamic compromise
* Absent breath sounds on auscultation
* Chest crepitations
* Subcutaneous emphysema
* Tracheal deviation
* Jugular venous distension
34
What are the specific treatments used to treat tension pneumothorax?
* Needle decompression - 2nd intercostal space midclavicular line or 4-5th intercostal space mid-axillary line ; use wide-bore non-kinking needle
* Open thoracostomy
* Clamshell thoracotomy
35
What durations of submersion are associated with good and poor outcomes?
* Submersion for 5-10 minutes associated with good outcomes
* Submersion for >20 minutes associated with poor outcomes
36
What modification should be made to ALS in drowned patients?
A, B:
* Give 5 initial ventilations
C:
* Pulse alone is poor sole indicator of cardiac output in wet cold drowned patients, use ECG and end-tidal CO2 as adjuncts as soon as possible
* Dry the patient's chest before applying defibrillator pads
* Most drowned patients are hypovolaemic, give fluids as soonas possible
37
What are the stages of hypothermia?
1. Stage 1 - mild hypothermia (conscious, shivering, core temp 35-32C)
2. Stage 2 - moderate hypothermia (impaired consciousness without shivering, core temp 32-28C)
3. Stage 3 - severe hypothermia (unconscious, vital signs present, core temp <24C)
4. Stage 4 - death due to irreversible hypothermia (core temp <11.8C)
38
What modifications should be made to ALS algorithm in hypothermic patients?
1. Withhold cardiac arrest drugs until temp >30C at which point double normal drug intervals until >35C when normal intervals can be restored
2. If initial VF, give up to 3 shocks but if unsuccessful, withhold further shocks until temp >30C
39
What are the methods for rewarming patients in hospitals?
1. Forced warm air
2. Warm IV fluids
3. ECMO
40
What are the critera for heat stroke?
1. Severe hyperthermia >40C
2. Neurological symptoms including confusion, seizures, coma
3. Exposure to high environmental temps or strenuous exercise
41
What modifications need to be made to ALS algorithm post-surgery?
Use adrenaline in increments rather than full 1mg at once
42
What modifications should be made in cardiac arrest post-cardiac surgery?
1. Use adrenaline carefully
2. If not responsive to 3 stacked shocks, for retrosternotomy and internal defibrillation of 20J
