ANAESTHETICS AND AIRWAY
ASTHMATIC INTUBATION
PromptPathophysiology of cardiovascular collapse of severe asthmatic during induction, intubation, and ventilation
ResponseOften ill for quite a while prior to arrival with decreased oral intake, so under volume to begin with
Typically have maximal endogenous sympathetic outflow - this decreases with induction >> relative vasodilation
Positive pressure ventilation with inadequate expiratory time >> raised intrathoracic pressure, decreased venous return, etc.
Consider pneumothorax.
Typically have maximal endogenous sympathetic outflow - this decreases with induction >> relative vasodilation
Positive pressure ventilation with inadequate expiratory time >> raised intrathoracic pressure, decreased venous return, etc.
Consider pneumothorax.
PromptGoals in preparation for intubation in asthma
ResponseImprove pre-oxygenation - use NIV FiO2 1.0 with PEEP 10cm.H2O
BP optimisation - IV fluids, N/S 1L Stat
Maximise bronchodilator therapy 0 IV adrnealine infusion starting at 5-10 mics/min
Optomise positioning - Sitting up for pre-oxygenation, pillow in situ
BP optimisation - IV fluids, N/S 1L Stat
Maximise bronchodilator therapy 0 IV adrnealine infusion starting at 5-10 mics/min
Optomise positioning - Sitting up for pre-oxygenation, pillow in situ
PromptModifications to RSI in Asthma
ResponseKetamine for induction (bronchodilator)
Bag through apnoea - aim to prevent hypoxia
Use largest ET tube to maximise flow and minimise resistance - limit peak pressure
Induce sitting up, recline on induction - goal to optimise oxygenation/ventilation as much as possible.
Bag through apnoea - aim to prevent hypoxia
Use largest ET tube to maximise flow and minimise resistance - limit peak pressure
Induce sitting up, recline on induction - goal to optimise oxygenation/ventilation as much as possible.
PromptHigh airway pressures in Asthma
ResponseTension Pneumothorax - throacostomy and ICC
Dynamic hyperinflation - disconnect, allow exhallation, tolerate hypercapnoea
Dyssynchorony - sedate and paralyse
Bronchospasm
DOPES
Dynamic hyperinflation - disconnect, allow exhallation, tolerate hypercapnoea
Dyssynchorony - sedate and paralyse
Bronchospasm
DOPES
PromptDynamic hyperinflation
Response= Autopeep = breath stacking
Casuses both high airway pressures AND/OR low BP
Disconnect and allow prolonged expiration
Casuses both high airway pressures AND/OR low BP
Disconnect and allow prolonged expiration
PromptVentilator settings in Asthma
(Paeds Q)
(Paeds Q)
ResponseRR <10 (8-10)
TV 5-7 mL/kg
Peak inspiratory pressure 35-50 to overcome high airway pressures (??)
PEEP 0-5 cm/H2O
I:E ratio 1:4-1:8 (1:4 seems a safe starting point, varies from 1:3 -1:8)
FiO2 aiming Saturatoins >90%, pO2>60
Permissive hypercapnoea
TV 5-7 mL/kg
Peak inspiratory pressure 35-50 to overcome high airway pressures (??)
PEEP 0-5 cm/H2O
I:E ratio 1:4-1:8 (1:4 seems a safe starting point, varies from 1:3 -1:8)
FiO2 aiming Saturatoins >90%, pO2>60
Permissive hypercapnoea