see also: [[Pregnant trauma#Pregnancy effect on resus]], [[Peri-intubation collapse]], [[Airway]] see: [Dunn - obesity](x-devonthink-item://CC6DFC88-D325-4642-875C-FD2EC539ADCA), [ACEM - Bariatric airway](x-devonthink-item://9125BB84-B3C0-42F2-93D9-2C5533BC9216?page=162) #tables | area | issue | | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | | airway | difficult intubation, preoxygenation anatomy<br>high incidence of reflux | | ventilation | difficult ventilation due to:<br>- ↓ chest wall compliance<br>- ↑ airway resistance<br><br>decreased FRC<br>increased oxygen consumption and CO2 production | | circulation | - difficult IV access +/- USS needed | | [[#doses]] | ↑ volume of distribution<br>- lipophilic drugs to real body weight, hydrophilic to ideal body weight<br>- accumulation of benzos and opiates | | imaging | - difficult EFAST<br>- CT scan weight restrictions | | interventions | - difficult ICC placement<br>- difficult landmarks | | pressure areas | need air mattress | | co-morbidities | more likely to have diabetes, CAD | **Resp effects** - high incidence of hypoxia - high incidence of hypercaponea - increased O2 consumption - increased CO2 produciton - reduced TLC and VC - decreased expiratory reserve vol (from collapse of small airways) - reduced functional reserve volume (declines exponentially as BMI increases) - increase WOB supine **non-resp effects** - increase intra-abdominal pressure - increased GORD - higher volume of distribution - increase CO2 production - increase incidence of hiatus hernia → aspiration risk # doses - propofol 1-2mg Ideal body weight - rocuronium 1.2-1.5 mg IBW - sux 1-2mg/kg *total body weight* - midaz 0.05-0.2 mg/kg/h IBW - vecuronium 0.1mg/kg IBW # Obesity RSI table | anatomical/physiological change | implication | modification to optimise | | ------------------------------------------ | --------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------ | | - increase UA soft tissue | poor laryngoscopic view | - videolaryngoscope, <br>- ramped position<br>- judicious use of D blade | | increased airway resistance | difficult BVM | - 2 handed BCM with OPA + NPA<br>- early LMA | | chest wall, breast, neck adiposity | - dificult FONA<br>- hard to get blade in | - pre-marking<br>- short handle | | decreased TLC, vital capacity, and FRC | smaller O2 reserve → rapid desaturation | pre-oxygenation with CPAP PEEP 10 or BVM + PEEP valve | | decreased thoracic wall and lung complianc | - higher rates of atelectasis<br>- high pressure ventilation<br>- difficult BCM and LMA | - position: upright until induction, ramp, intubate at 30 deg<br>- reverse trendelenburg<br>- PEEP for recruitment | | increased O2 consuption and CO2 production | rapid desaturation | HFNP at 15L O2 apoenic oxygendation | | increased intrabdominal pressures | - smaller O2 reserve<br>- high pressure ventilation | reverse trendelnburg position | | increased risk of CICO | be prepared | second operator ready to go if needed |