Intravenous injection, nerve agents

The immediate treatment for nerve agent intoxication is intravenous injection of 2 mg atropine sulfate (intramuscular injection should be considered if the patient is hypoxic and ventilation cannot be initiated, as there is a risk of ventricular fibrillation). This should be followed by additional injections of atropine at 10-15 min intervals, continuing until bradycardia has been reversed (e.g., until the heart rate is at 90 beats per minute). If breathing has stopped, a mechanical respirator should be used to ventilate the patient. Mouth-to-mouth resuscitation should not be attempted. If possible, oxygen or oxygen-enriched air should be used for ventilation. If possible, cardiac activity should be monitored. 

In mass casualty situations, intravenous antidotes may not be available. In that case, the intramuscular administration is acceptable. Most Emergency Medical Systems in the United States now stock military Autoinjector units containing atropine and pralidoxime, although kits with pediatric doses may not be available. However, in critical situations, children older than 2 or 3 years of age weighing at least 13 kg might benefit from 2 mg of atropine and 600 mg pralidoxime administered intramuscularly with auto-injectors (7). Experience with the accidental atropine auto-injection in 240 Israeli children unexposed to nerve agents revealed that... 

During the clinical usage of oxime for the treatment of poisonings with nerve agent or OPI, we must be fully aware of the possible occurrence of oxime-induced side effects. The rapid intravenous injection of pralidoxime can produce drowsiness, headache, disturbance of vision, nausea, dizziness, tachycardia and... 

There are only a few reports in the open literature on the effect of oximes in nerve agent-exposed humans. Pralidoxime chloride was very effective in reactivating erythrocyte AChE in individuals exposed to sublethal intravenous or oral VX while this oxime was substantially less effective in humans exposed to IV sarin (Sidell and Groff, 1974). Accidental sarin exposure by inhalation resulted in an initial progressive deterioration (coma, apnea) of the patient despite atropine and 2-PAM treatmentand substantial recovery of erythrocyte AChE activity (Sidell, 1974). It took several hours until the patient s condition improved. Sidell also reported an accidental oral soman exposure. A lethal dose of diluted soman splashed into and around the mouth of an individual, resulting in coma, bronchoconstriction and respiratory depression, which was successfully treated with repeated atropine injections. 2-PAM (2 g IV) had no effect on inhibited erythrocyte AChE. 

Local anesthetics are widely used to provide anesthesia via local subcutaneous Injection topical application to skin and mucous membranes and epidural, spinal, and regional nerve blocks. In addition, lidocaine (see p 462) is used intravenously as an antiarrhythmic agent and cocaine (see p 171) is a popular drug of abuse. Gommonly used agents are divided into two chemical groups ester-linked and amide-linked (Table 11-2). 

Local anesthetics are used to locally anesthetize a wide range of specific body parts or areas to allow painless surgery. Local anesthetics are most commonly used for dental procedures and repair of lacerations. They can also be used to provide neural blockade for larger, more painful procedures. Sites of LA application include localized injection, peripheral nerve blocks as well as central nerve blockade. The only safe agents which can be utilized for intravenous regional anesthesia (Bier block) are lidocaine and prilocaine. Other typical indications are outlined in Table 64.1. 

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