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Education And Debate

Nuclear terrorismCommentary: The myth of nuclear deterrence in south AsiaCommentary: The psychology of terrorists

BMJ 2002; 324 doi: (Published 09 February 2002) Cite this as: BMJ 2002;324:356

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Dear Sir - Russian government revealed to have used a gas mixture,
including fentanyl and halothane, to incapacitate Chechen terrorists in
the attempt to liberate the hostages in Moscow (1). Only recently, someone
contested the official explanation provided by Russian government. This
theory has been confuted by elementary notions about clinical and
pharmacokinetic characteristics, which make these products unable to
produce the disastrous effects observed at Moscow theatre (2).

Carfentanil is a potent opioid which is used as rapid immobilizing
agent for veterinary procedures in large wild animals, like bisons, bears,
elks, ostriches, horses or domestic goats, often associated with other
agents, like xylazine or detomidine, by darting (even from a helicopter),
or delivering directly in the buccal cavity. Time to immobilization
appears to be dose-dependent and more rapid than that produced by
etorphine, another rapid and potent opioid agonist (3). Carfentanil
induces rapid catatonic immobilization, characterized by limb and neck
hyperextension. Undesidered adverse effects of immobilization are muscle
rigidity, bradypnea, and oxygen desaturation. Of interest, recycling and
renarcotization has been reported as possible cause of death of animals
treated with a relatively low dose antagonist regimen, and a high ratio
naloxone-carfentanil is required (4).
It is likely that massive doses of carfentanil were used (the way to
delivery by inhalational route and saturate the room space remains
mysterious) in the theatre to obtain the fastest and maximum possible
effect with the terrorists, but without taking into account the high
possibilities of hostage involvement and, as it happens in immobilizing
animals where doses cannot be precisely delivered, some victims would be
expected. In the theatre naloxone syringes were found and it is possible
that naloxone doses were not enough to reverse respiratory insufficiency,
as it occurs in animals, which die as a complication of immobilization.

Authorities should really give clear explanation, rather than
providing generic and not exhaustive information, to the scientific world.

Sebastiano Mercadante

Anesthesia and Intensiv Care Unit & Pain Relief and Palliative Care
La Maddalena Cancer Center, Palermo, Italy


1 - Schiermeier Q. Hostage deaths put gas weapons in spotlight.
Nature 2002;420:7.

2- Rieder J, Keller C, Hoffmann G, Lirk P. Moscow theatre siege and
aneshetic drugs. Lancet 2003;361:1131.

3- Heard DJ, Nichols WW, Buss D, Kollias GV. Comparative cardiopulmonary
effects of intramuscularly administered etorphine and carfentanil in
goats. Am J Vet Res 1996;57:87-96.

4- Miller MW, Wild MA, Lance WR. Efficacy and safety of naltrexone
hydrochloride for antagonizing carfentanil citrate immobilization in
captive Rocky Mountain elk (Cervus elaphus nelsoni). J Wild Dis

Competing interests:  
None declared

Competing interests: No competing interests

04 June 2003
Sebastiano Mercadante
La Maddalena Cancer Center,90145 Palermo