Carbon monoxide

Chemical asphyxiant

Binds to Hb with 240x more affinity than 02.

FORMS CARBOXYHB

Main SOURCES

Cigarettes smoke

Vehicles

Workplace

OEL and BEI from the notes

50ppm for oel

8% COHB in blood end shift

Baseline COHB in smokers

5-7% with levels of 10% not unusual

Impact of ventilation

Resting can be 6% COHB at 50ppm over 8hours

Working can be 8% COHB at 50ppm over 8hours

CO reduces the max O2 consumption during exercise by the same % bound to hb

E.g COHB 5% leads to 5% decreased O2 consumption

Symptoms in sequence

Start at 10% - Headache

Followed by tinnitus and giddiness at 20%.

Mental clouding at 30%

Coma and death abover 35%

Fatal arrythmias at lower levels if underlying CVS disease

True

Risk factors for MI in CO

Hot environment, dehydrated, increased CO and O2 consumption e.g. firefighters

Half lifes

COHB 4 hours at room air

100% 02 face mask is 60 to 90min

Ventilation is 60min

18min HBOT

Do Ecg , cardiac enzymes and hospitalise at least 24hours if COHB is more than 25

True

Long term effects

CNS, severe headaches or even permanent. Usually better by 6 months

CO in pregnancy

Binds Strong to fetal hb

Prevention

Enclosed spaces

CO monitoring and oel

Ventilation

Smoking and sources of CO

Don't allow CVS and respiratory problem workers

SBCA

Information education training

CPR, 100% O2 available