EMP 194/198
Common
Toxicological Emergencies and Overdoses
And Their
Pre-hospital Treatment
|
Toxidromes |
Signs and
Symptoms |
Treatments |
|
1.)
Acetaminophen |
0.5 to 24 hours –
anorexia, n/v, malaise, diaphoresis |
n
Airway
support n
Activated
charcoal n
N-acetylcysteine
(NAC) either orally or intravenously n
Lavage
if the patient presents within 2 hours of ingestion n
Liver
transplant has been performed as a lifesaving measure in rare cases |
|
24 to 48 hours –
ABD pain, liver tenderness, oliguria |
||
|
72 to 96 hours –
hypoglycemia, jaundice, encephalopathy |
||
|
4 days to 2 weeks
– hepatotoxicity and hepatic failure |
||
|
2.) Anticholinergics Examples: antihistamines, antiparkinsonians,
antiemetics, atropine, tricyclics, and mushrooms |
Peripheral Signs: Dry skin and mucous Membranes, Thirst,
Dysphagia, Blurred vision, Fixed dilated pupils, Tachycardia, Fine red
(scarlatiniform) rash, Hyperthermia, Abdominal distension with
decreased/absent bowel sounds, Urinary urgency or retention |
n
Conservative
supportive care n
Monitor
airway, breathing, and circulation n
Establish
IV access n
Cardiac
monitoring n
Activated
charcoal may be useful (1g/kg up to 50g) n
Supportive
care n
Lavage
even late in overdose n
Seizures
and agitation are treated with benzodiazepines. n
Dysrhythmias
can be treated. |
|
Central Signs:
Lethargy, Confusion, Restlessness, Delirium, Hallucinations, Ataxia,
Seizures, cardiopulmonary collapse |
||
|
3.) Neuroleptics (cont’d) Examples: Haldol, deoperidol, Seroquel, Zyprexa,
Geodon |
Adverse reactions
are common and may occur even in the setting of normal therapeutic dosages. Including: Dystonic reaction Akathisia Parkinsonism Tardive dyskinesia Neuroleptic malignant syndrome (NMS) (10% mortality rate) Hyperthermia Rigidity Altered mental status |
n
ABCs n
Cardiac
monitoring n
Nalaxone n
Glucometer
reading n
Treat
hypotension with crystalloid and dopamine. n
Ventricular
dysrhythmias – treated with bicarbonate, then lidocaine n
Torsades
de pointes – treated with
magnesium n
Seizures
should be treated using standard methods n
Activated
charcoal (1g/kg up to 50g) and gastric lavage n
Cooling
or warming techniques may be needed |
|
4.) Beta Blocker’s |
Bradycardia, AV blockade, Hypotension, Tachycardia, LOC changes , Bronchospasm Congestive heart failure, Masks S/S of hypoglycemia, Impairs recovery
from, hypoglycemia |
n
Supportive
care n
Activated
charcoal may be indicated (1g/kg up to 50g) n
May
respond to atropine or epinephrine n
Usually
require glucagon 3-10 mg IVP n
Fluid
therapy n
Transcutaneous
pacing n
Treat
seizures n
Treat
bronchospasm with a β2-agonists n
Continuous
glucagon infusion n
Vasopressor
therapy (dopamine or epinephrine) |
|
5.) Calcium Channel Blocker’s |
Dependent on the specific agent ingested, Hypotension, Bradycardia, AV
conduction blocks, Lethargy and slurred speech, N/V, Coma, Respiratory
depression |
n
Supportive
care n
Activated
charcoal may be indicated (1g/kg up to 50g) n
Calcium
therapy, 10 cc of a 10% solution IVP n
Atropine
or isoproteronol n
Transcutaneous
pacing n
Glucagon
IVP has limited success n
IV
fluids n
Inotropes
(dopamine or epinephrine) |
|
6.) Carbon Monoxide |
·
<
10% – generally asymptomatic ·
10–20%
– headache and dyspnea ·
20–30%
– headache, fatigue, and visual disturbance ·
40–50%
– tachycardia and altered level of consciousness; may precipitate angina ·
60% –
coma, seizures, cherry-red skin Levels can only be
measured via blood testing. Levels > 40%,
any organ system can be affected Central nervous system Pulmonary system Cardiovascular system |
n
Supportive
care n
Airway
management n
Supplemental
O2 via NRB n
Measuring
SpO2 is unreliable n
Use of
hyperbaric oxygen therapy for the following: => For patients with significant neurological abnormalities =>Patients with cardiovascular abnormalities =>Symptomatic pregnant patients |
|
7.) Cyanide |
Present very
quickly post-exposure, Unconscious, Noncyanotic, Hypotensive, Bradycardia, Death
occurs in seconds to minutes. Less severe cases or very early post-exposure:
|
n
Recognition
of cyanide exposure is the key n
Initial
supportive care, including ABCs n
A
specific antidote, known as the Pasadena Cyanide Antidote Kit, is available. n
The
kit contains three different products: n
Amyl
nitrite pearls for inhalation n
Sodium
nitrite solution for intravenous use n
Sodium
thiosulfate for intravenous use n
Smoke
inhalation cases require treatment for cyanide and carbon monoxide toxicity. n
IV hydroxycobalamin
(vitamin B12) n
For
oral cyanide ingestion, charcoal (1g/kg up to 50g) |
|
8.) Cyclic Antidepressents Examples: Elavil |
Dizziness, Confusion, Blurred vision, Dry mouth Signs classified into three categories: ·
Cardiovascular ·
CNS ·
Anticholinergic Cardiovascular signs include: ·
Conduction
blocks, hypotension, dysrhythmias, and cardiac arrest CNS signs include: ·
Delirium,
agitation, extrapyramidal signs, myoclonus, seizures, and coma Anticholinergic signs include: ·
Tachycardia,
mydriasis, decreased bowel sounds, urinary retention, and hyper- or
hypothermia ·
The
earliest and most sensitive sign of cyclic antidepressant overdose is
tachycardia. ·
Life-threatening
dysrhythmias are generally preceded by prolongation of the QRS complex. |
n
Supportive
care, including ABCs n
Multi-dose
activated charcoal (1g/kg up to 50g) n
IV
access and fluid therapy are indicated if hypotensive n
Sodium
bicarbonate remains a mainstay of therapy n
Hypotension
unresponsive to bicarbonate and IV fluid may require inotrope therapy (dopamine) n
Seizure
activity unresponsive to bicarbonate therapy may be treated with
benzodiazepines n
Gastric
lavage may be indicated if less than 2 hours postingestion n
Cases
of suspected toxicity require an observation period of at least 6 hours. |
|
9.)Digoxin or Digitalis (cont’d) |
Virtually any
cardiac dysrhythmia can be seen. Symptoms are
nonspecific and include: ·
Fatigue ·
Anorexia ·
Disorientation
and confusion ·
Delerium
and hallucinations ·
Gastrointestinal
upset ·
Visual
halos (green or yellow) |
n
Supportive
care, including ABCs n
Fluids
and pressor agents for hypotension n
Multi-dose
activated charcoal may be useful. n
Calcium,
which will worsen digoxin toxicity, should not be given. n
Correct
electrolyte abnormalities n
Magnesium
may lessen cardiac toxicity. n
Phenytoin
may be helpful for ventricular dysrhythmias. n
Atropine
and pacing may be required for symptomatic bradycardias. |
|
10.) Ethylene Glycol |
Phase I: 1 to 12 hours post-ingestion Signs of intoxication without the smell of
ethanol, CNS symptoms may include ataxia, seizures, and nystagmus. N/V. Phase II: 12 to 36 hours post-ingestion Cardiopulmonary toxicity Hypertension, Tachycardia,
Tachypnea, Pulmonary edema (severe poisoning), Congestive heart failure
(severe poisoning), Shock (severe poisoning) Phase III: 24 to 72 hours post-ingestion Acute renal toxicity, Flank pain, Costovertebral
angle tenderness, Decreased urine output, Acute renal failure |
n
Supportive
care, including ABCs n
IV
fluids for dehydration and renal perfusion n
Ethanol
therapy is indicated as a means of preventing metabolism to toxic
metabolites. n
Metabolism
to toxic metabolites is limited by administering ethanol as a competitive
inhibitor of alcohol dehydrogenase. n
Hemodialysis
is indicated in cases of renal failure. n
Bicarbonate
is used in cases of profound acidosis. |
|
11.) Iron and other Heavy Metals (Pb, Au, Ag, Ni, Cu) |
Stage 1: 1/2-2 hours
post-ingestion Severe vomiting and diarrhea, Lethargy, Coma, Pallor, Tachycardia,
Hypotension, Acidosis, Hyperglycemia, Hypovolemia, Shock, Renal failure, Death Stage 2: 2 to 12 hours
post-ingestion Relatively
asymptomatic period Stage 3: 12 to 48 hours
post-ingestion Recurrence of GI
symptoms GI perforation, Coma,
Seizures, Shock, Hepatorenal failure, Coagulation defects, Hypoglycemia, Severe
metabolic acidosis Stage 4: Beyond 48 hours post-ingestion, Pyloric (gastric outlet) strictures, Either
death or recovery occurs |
n
Supportive
care including ABCs n
Fluid
resuscitation in cases of volume depletion n
Whole-bowel
irrigation is the decontamination method of choice. n
Iron toxic
levels are treated with deferoxamine. n
All
other heavy metals are treated with BAL (British Anti-Lewisite) chelating
agent |
|
12.) Isopropyl Alcohol (rubbing
alcohol) |
Signs of
intoxication CNS depression may
appear. Twice as potent a
CNS depressant as ethanol, Hypotension that is unresponsive to fluids, Cardiac ischemia
or infarction can occur. |
n
Supportive
care, including ABCs n
Assisted
ventilation and fluid therapy as needed n
Gastric
lavage and activated charcoal may be indicated for recent ingestions. n
Ethanol
therapy is not indicated. n
Vasopressor
therapy, though of limited value, may be tried. n
Dialysis
may be indicated in cases involving severe hypotension. |
|
13.) Lithium |
Low (serum levels < 1.5 mEq/L) – nausea, vomiting, and diarrhea Moderate (serum levels 1.5 to 3.0 mEq/L) – polyuria followed by urinary
and fecal incontinence, muscle weakness, and neurological symptoms Severe (serum levels > 3.0 mEq/L) – seizures, coma, cardiac dysrhythmias,
hypotension, and muscle twitching |
n
Supportive
care including ABCs n
Aggressive
fluid resuscitation n
Lavage
if < 1 hour since ingestion n
Whole-bowel
irrigation n
Correction
of volume depletion is essential n
Hemodialysis
in cases of renal failure, of severe cardiovascular or neurological
abnormalities, or with high serum levels |
|
14.) Narcotics and Opioids |
Miosis (pinpoint
pupils) Respiratory
depression, Decreased level of
consciousness, Occasionally seizures, hypotension, and ventricular
dysrhythmias can be seen. |
n
Supportive
care, including ABCs n
Naloxone
(Narcan) may avert the need for invasive airway control. n
Ensure
patient and care providers safety. n
Consider
prophylactic use of restraints. n
Duration
of IV naloxone is 20-120 minutes n
Duration
of most opioids is 3-6 hours n
Continuous
naloxone infusion may be indicated. |
|
15.) Organophosphates, Carbamates, and Nerve
Gases |
CNS symptoms include agitation, drowsiness, seizures, cardiorespiratory
depression, coma, and death. Miosis is typically present, but in 10% of cases mydriasis is present. A garlic odor may be present. |
n
Supportive
care, including ABCs n
Ensure
caregiver safety n
Atropine
reverses the cholinergic symptoms. n
0.5-1
mg every 2 to 5 minutes n
Maximum
of 100 mg n
Pralidoxime
(2-PAM) n
Charcoal
and lavage for oral ingestions |
|
16.) Salicylates Example: ASA |
Mild to moderate – tachypnea, vomiting, diaphoresis, tinnitus, and
acid–base disturbances Severe – CNS abnormalities ranging from confusion and delirium to coma
secondary to cerebral edema, hypoglycemia (rare), pulmonary edema,
coagulopathies and platelet dysfunction, and occasionally hyperthermia |
n
Supportive
care, including ABCs n
Activated
charcoal n
Hypoglycemia
should be ruled out. n |