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Antivenin với rắn và nhện cắn

General Principles		Medical Management Principles
Exposure to radiation source (x-rays, gamma rays, neutrons, protons—high dose over short period—minutes) can cause tissue injury. Patients do not become radioactive. External contamination: loose particles of radioactive material are deposited on surfaces, skin, clothing Internal contamination: radioactive material is inhaled, ingested, or lodged within wound. Contaminated patients should be decontaminated as soon as possible		Establish triage area for contamination containment and decontamination Remove contaminated outer garments of patients and staff and double bag using radioactive waste guidelines Body survey staff and patient with radiation meter Wash wounds and skin with saline/soap and water Resurvey and repeat washing until radiation level no more than twice background or unchanged
Additional Resources Armed Forces Radiobiology Research Institute Medical Radiobiology Team 1-301-295-0530 www.afrri.usuhs.mil Centers for Disease Control and Prevention 1-800-CDC-INFO www.bt.cdc.gov/radiation		Radiation Emergency Assistance Center/ Training Site (REAC/TS) 1-865-576-3131 (M-F day) 1-865-576-1005 (After hours) www.orau.gov/reacts
Acute Radiation Syndromes Dose Exposure		Signs, Symptoms, Outcome
Bone marrow >0.7 Gyb (70 rads) mild • Anorexia, nausea, vomiting syndrome symptoms with 0.3 Gy^ • May have latent period of (30 rads) appearing well Primary cause of death is infection and hemorrhage Gastrointestinal >100 Gyb (1,000 rads) same • Anorexia, nausea, vomiting, syndrome symptoms with 6 Gy (600 cramps, diarrhea rads) • May have latent period of appearing well Death due to infection, dehydration, electrolyte abnormalities 100% lethality ~10 Gy Cardiovascular/central >50 Gyb (5,000 rads), some • Nervousness, confusion, nervous system symptoms with 20 Gy nausea, vomiting, diarrhea, syndrome (2,000 rads) loss of consciousness, burning sensation of skin May have partial return of function for hours Death within 3 days of this level of exposure
(continued)
TABLE 12.7. (continued) Radiation Exposure Emergencies
If Radiation Exposure Suspected:
Triage	Diagnosis of acute		Initial treatment and
	radiation syndrome		diagnostic evaluation
• Airway, ventilatory,	• Diagnosis is difficult and		• Treat vomiting
and circulatory	depending on dose, signs		• Record clinical symptoms
support	and symptoms may occur		including nausea, vomiting,
• Physiologic	within hours or days or be		diarrhea, and itching,
monitoring	in a latent stage		reddening, or blistering of skin
• Treat major trauma,			with time of onset (see Table
burns, and respiratory			12.8)
injury
• Obtain blood samples	• If exposure occurred		• Consider tissue, blood typing,
for complete blood	within 8-12 h, repeat		and initiating viral prophylaxis
count with	complete blood count		• Consultation with radiotherapy
differential (attention	with attention to		and hematology experts
to lymphocytes) and	lymphocyte count q2-3h		regarding dosimetry,
HLA typing prior to	for first 8-12 hrs after		prognosis, and treatment
transfusion	exposure and then q4-6h		options
	for the following 2-3 d		• Prophylaxis and treatment of
	(see Andrews nomogram		infections
	Table 12.8)		• Use of hematopoietic growth
			factors and/or stem cell transfusions
			• Chromosome aberration
			cytogenic bioassay best method of dose assessment
a Adapted from www.bt.cdc.gov/radiation.
^Exposure of entire body	to high dose (>0.7 Gray (Gy)		or >70 rads) radiation (i.e., x-rays,
gamma rays, neutrons) for short periods of time (usually minutes) resulting in immediate tissue injury and depletion of immature parenchymal stem cells. Symptoms can be immediate or delayed, mild, or severe, depending on radiation dose. Nausea and vomiting may occur minutes
to days after the exposure. The time of onset of vomiting and dose exposure estimation (Table 12.8).			is a major sign to assist in diagnosis