Heart sarin

Not all toxic organophosphoms compounds have uses beneficial to humans. Sarin is an extremely toxic nerve gas that is lethal to humans. In March 1995 this substance was released in a terrorist attack on a Japanese subway, resulting in several deaths and many serious injuries. Sarin and related nerve gases bind an amino acid in the enzyme responsible for muscle action. When this enzyme is deactivated, muscles contract but cannot relax. Even a small dose can be lethal if the nerve gas reaches the muscles of the heart. 

Based on the experience of Iranian physicians who treated sarin toxicity during the Iran-Iraq war (Newmark, 2004), PAM was not available on the front lines and atropine alone was used for treatment. The doses of atropine used were considerably higher than those used in the Tokyo subway sarin attack, or that are generally recommended in the USA (Medical Letter, 2002). The Iranian protocol called for initial administration of 4 mg intravenously. If no atropine effects (improvement in dyspnea or decrease in airway secretions) were seen after 1 to 2 min, 5 mg was then administered intravenously over 5 min while heart rate was monitored. A rise in heart rate of 20 to 30 beats per min was regarded as an atropine effect. In severe cases, 20 mg to 200 mg was given. Regardless of dose, the key to saving lives, in their opinion, was how soon the atropine was administered. 

In a later study (MOD12), 14 subjects exposed to a Ct of 14.7 mg min m 3 of sarin (mean erythrocyte inhibition of 50%) carried one-third of their body weight up and down a 40.5-cm step 30 times a minute for 5 min (the Harvard pack test). This was done 45 min and 24 h after exposure. Their fitness index, which includes heart rate and other measures, did not differ from that of a group exposed to agent but not exercised. 

Using a low-frequency critically damped bal-listocardiograph, cardiac output was estimated in 25 subjects given 5 pg kg-1 of sarin by oral inhalation (which caused a mean 37% decrease in erythrocyte cholinesterase activity). There was a small increase in heart rate, which the investigator felt was a cortical response to the sensation... 

In September 1939, as scientists in Berlin prepared the first samples of sarin, the German army launched its invasion of Poland. For the second time in a generation, German chemists were at the heart of their country s war effort. On 19 September, after almost... 

Cyanide concentrations in tissue, such as liver, lung, spleen, and heart, may be more accurate indicators of the blood cyanide intoxication levels. Estimates of tissue levels are necessary adjunctive studies in forensic cases.38 For details on collecting and analyzing blood and tissue for cyanide, see Assay Techniques for Detection of Exposure to Sulfur Mustard, Cholinesterase Inhibitors, Sarin, Soman, GF, and Cyanide, Technical Bulletin Medical 296.39 Principles of Therapy... 

Dabisch, P.A., To, E, Kerut, E.K., et al., 2007a. Multiple ejqxjsures to sarin vapor result in parasympathetic dysfunction in the eye but not the heart. Toxicol. 

In the study by Little et al. (1986), a single sublethal dose (80pg/kg) of radiolabeled sarin was administered intravenously to mice and the tissue distribution was followed for 24 h. Within Imin, sarin was distributed to the kidneys, lungs, brain, liver, heart, and diaphragm. Thereafter, tire concentrations in all tissues rapidly declined, and within 15 min only trace quantities of [ FI] sarin were found in the brain. Within the first minute, approximately half of the labeled sarin was in the form of IMPA. The highest concentrations of sarin and its... 

Animal data indicate that nerve agents rapidly distribute to the brain, lungs, heart, diaphragm, kidneys, liver and plasma. The concentrations in all tissues initially decline rapidly, followed by a second more gradual decline, reflecting metabolism and urinary elimination, respectively. The measurement of the hydrolysis product of sarin [0-isopropyl methylphosphonic acid (IMPA)] in urine may be used for retrospective detection of exposure, although it is... 

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