Chemical Agents of Opportunity for Terrorism: TICs & TIMs

Chemical Agents of Opportunity for Terrorism
Training Support Package
Participant Guide
Slide 33
Chemical Agents of Opportunity for Terrorism:
TICs & TIMs
Convulsions: Management
• Benzodiazepines
• Barbiturates, propofol
• Pyridoxine
– Empiric dose, 5 gms (70 mg/kg)
Excitation
Inhibition
Excitation
Inhibition
Module Two - The Clinical Neurotoxicology of Chemical Terrorism
33
The clinical management of seizures attempts to balance the loss of inhibitory tone by
supplying a sedative that enhances inhibitory tone. Examples of sedatives that are
given to control excitation and seizures include benzodiazepines, barbiturates and
propofol.
In selected circumstances, pyridoxine is also used, although it is not a sedative. It is a
critical co-vitamin whose administration along with a benzodiazepine may be required in
poisoning by monomethylhydrazine (rocket fuel) or INH (an anti-tuberculosis
medication).
Excitatory toxins cause convulsions and seizures which if prolonged can be rapidly fatal.
The best way to treat this is to give inhibitory drugs or agents to stop the convulsions
and seizures. Overly excited states are generally much more dangerous than overly
inhibited states. In addition to the seizures and convulsions many excitatory agents
cause changes in heart rate and blood pressure and other bodily functions that are often
difficult to manage. In some cases the best treatment for an overly excited state is to
use inhibitory agents to place the patient in a comatose and overly inhibited state which
is easier to manage and can be maintained until the excitatory toxin effect has worn off.
Benzodiazepines, barbiturates, and propofol are all examples of available
pharmaceutical agents that can be used to produce inhibition and at high doses can be
used to place the patient in a comatose state. Pyridoxine refers to vitamin B-6 which as
described in the previous slide may be needed to treat convulsions and seizures from
hydrazines or other compounds that interfere with normal vitamin B-6 usage in the brain.
Although we give sedative agents to patients presenting with excitation, we never give
excitation agents to patients with coma because the complications of causing undue
excitation in these previously comatose patients outweighs the benefits of suddenly
waking them up. Naloxone which is not a stimulant awakens opioid intoxicated patients
NOT by stimulating them but by actually BLOCKING the opioid receptors and preventing
continuing opioid effects.
December 2008 Version 2.0 Page 102