L1: General Toxicology Flashcards
1
Q
Def of Toxicology
A
Science dealing with
- Properties
- Actions
- Toxicity
- Autopsy findings (in case of death, in relation to poisonous substances).
- Fatal dose
- Detection
- Estimation
- Treatment
2
Q
What is a Toxicant?
A
Specific chemical poisonous.
3
Q
Categorization of toxic effects
A
- Toxic effects are categorized according to site of poison effect.
- In some cases, effect may occur at only one site, This site is referred to as specific target organ.
- In other cases, toxic effects may occur at multiple sites.
4
Q
Types of systemic toxicity
A
- Acute toxicity
- Subacute toxicity
- Chronic toxicity
5
Q
Onset of Acute Toxicity
A
- occurs almost immediately (hours/days) after an exposure.
6
Q
Causes of Acute Toxicity
A
usually a single dose or a series of doses received within one day.
7
Q
Onset of Subacute Toxixity
A
results from repeated exposure for several weeks or months.
8
Q
Causes of Subacute Toxixity
A
This is a common human exposure pattern for some pharmaceuticals and environmental agents
9
Q
Onset of Chronic Toxicity
A
- It represents cumulative damage to specific organ systems
- takes many months or years to become a recognizable clinical disease.
10
Q
Causes of Chronic Toxicity
A
- Damage due to subclinical individual exposures may go unnoticed but with repeated subclinical exposures, cumulative damage slowly builds up until it exceeds threshold for chronic toxicity.
11
Q
Manners of posining
A
Suicidal (Deliberate): Overdose as self-harm.
Accidental: Most episodes of pediatric poisoning, dosage error or iatrogenic.
Homicidal
12
Q
what are poisons classified according to?
A
- According to their mode of action
- According to the organs affected: (Target Organ Toxicity).
- According to the chemical nature
13
Q
Classification of poisons, according to their mode of action
A
- Poisons with local action
- Poisons with remote action
- Poisons with both local and remote actions
14
Q
what are posions with local action? and are examples for them?
A
- They act locally producing immediate destruction of tissues with which they come in contact
e.g., corrosives (except organic acids)
15
Q
Def of poisons with Remote action
A
They act only after absorption without any local effects
16
Q
Examples of poisons with Remote action
A
plant poisons which act mainly on CNS.
17
Q
Def of poisons with Local & Remote action
A
which have a local irritant action on tissues, they come in contact for some time and a remote action (on parenchymatous organs) after absorption.
18
Q
Examples of poisons with Local & Remote action
A
irritant metallic poisons
19
Q
Classification of poison according to organ affected
A
- Neurotoxic (Brain)
- Hepatotoxic (liver)
- Nephrotoxic (Kidney)
- Cardiotoxic (Heart)
- Immunotoxic
- Respiratory System
- Reproductive System
20
Q
Examples of Neurotoxic (brain) toxins
A
- Alcohol
- Lead
21
Q
Examples of Hepatotoxic (Liver) toxins
A
- Ethanol
- Acetaminophen
- Phosphorus
- Carbon Tetrachloride.
22
Q
Examples of Nephrotoxic (Kidney) toxins
A
Heavy metals e.g., mercury.
23
Q
Examples of Cardiotoxic (Heart) toxins
A
Digitalis.
24
Q
Examples of Immunotoxic toxins
A
Isocyanates.
25
Examples of Respiratory System toxins
- Tobacco smoke
- Asbestos
- Ozone.
26
Examples of Reproductive system toxins
Di-bromochloropropane.
27
classification of toxins, according to the chemical nature
- Acids
- Alkalis
28
Examples of acids
- Sulphuric acid
- Nitric acid
- Hydrochloric acid.
29
Examples of alkalis
Caustic soda
Caustic potash
Ammonium hydroxide
30
What are factors affecting the severity of toxicity?
- Factors related to the person
- Factors related to the poison
31
Factors related to the person affecting severity of toxicity
- Age of the person
- Genetic factors
- Personal hypersensitivity
- Tolerance
- Idiosyncrasy
- State of health
- Condition of the stomach
32
How does age affect the severity of toxicity?
- Children and old people are generally more susceptible to toxic agents
33
Why are children and people more susceptible to toxic Asians?
Due to decrease of detoxification power.
34
What can children tolerate, and what can't they?
Children can tolerate action of atropine, but not morphine.
35
Person suffering from G6PD deficiency are susceptible at therapeutic doses to hemolytic effect of some drugs like ........
vitamin K and sulphonamides.
36
Genetic factors affecting severity of toxicity
Persons suffering from glucose-6-phosphate dehydrogenase deficiency are susceptible at therapeutic doses to hemolytic effect of some drugs
37
How does personal hypersensitivity affect severity of toxicity?
Very small harmless doses can produce severe symptoms in sensitive patients
38
Drugs, which are most commonly associated with personal hypersensitivity
Therapeutic dose of penicillin or iodine may produce anaphylaxis in hypersensitive patients.
39
Describe tolerance
where addicts can stand big dose without ill-effect, So, they have to increase the dose to get same effect.
40
What causes tolerance?
- Repeated intake of substances of abuse leads to development of tolerance
- So, they have to increase the dose to get same effect.
41
What is idiosyncrasy?
- Abnormal response to some drugs
42
Drugs associated with idiosyncrasy
Morphine may produce convulsions instead of depression of CNS.
43
How does state of health affect severity of success?
Patients suffering from liver or kidney diseases may show signs of increased toxicity of poisons.
44
Aspects of **condition of the stomach**
- Type of food
- Gastric secretion
45
How does type of food affect severity of toxicity?
- Fatty foods delay absorption of arsenic
- while they increase absorption of some poisons as DDT and phosphorus.
46
How do gastric secretions affect severity of toxicity?
- Poisoning with potassium cyanide may not be fatal
- In case of achlorhydria: as HCL in stomach is important to form severely toxic hydrocyanic acid.
47
How does state of the poison affect severity of Toxicity?
Poisons in gaseous form are more rapidly absorbed
48
Factors related to the poison, affecting severity of toxicity
- State of the poison
- Routes of poison administration
- Dose of the poison
- Cumulation
49
What form of poisons is most Rapidly absorbed?
- Gaseous form are more rapidly absorbed
- Followed by:
Liquid
Fine powder
Big lumps.
50
Route of administration causes the quickest toxicity?
51
General scheme for approach of a poisoned patient
52
what questions should history taking in poisoning include?
- Type of toxins (What)
- Time of toxic exposure (acute versus chronic). (When)
- Amount of toxin taken (How much)
- Route of toxin administration (i.e. ingestion, intravenous, inhalation) (How.).
- Manner of the toxic ingestion or exposure. (Why)
53
How does Dose of the poison affect severity of Toxicity?
The bigger the dose, the more toxic effect
54
History taking in poisoning
- History of sudden appearance of toxic manifestations in a healthy person or a group of persons after taking certain food or drink (as food poisoning, methanol and carbon monoxide toxicity).
- History of intake a poison, financial problems, psychiatric troubles, provious altempts at suicide or threatening by somebody.
- History of presence of bottle.of tablets or insecticide near the victim.
- History of patients rescued from fire (CO, cyanido).
55
Diagnosis of poisoning
- History & Circumstantial evidence
- Clinical Examination: (General & Local)
- Investigations
56
Psychiatric information in poisoning history Taking
- History of psychiatric illness or previous suicide attempts.
57
cumulation of poison & its relation to severity of toxicity, then give examples for some drugs that may be accummilated in this way
- After repeated small doses of certain drugs which are not readily metabolized,
- The effect of a single large dose is reached leading to poisoning e.g., digitalis.
58
What information should history in poisoning include?
- Psychiatric Information
- Drug(s) Information
- Unavailable Information
59
Drug information in poisoning history Taking
- Information about all drugs taken, including prescription, over the counter medications, vitamins, and herbal preparations.
60
Examples of Toxidromes
- Sympathomimetic
- Anticholinergic
- Hallucinogenic
- Opiod
- Sedative - Hypnotic
- Cholinergic
61
What to do if there is unavailable information in poisoning history Taking?
- If history is unavailable from patient, information should be taken from family and friends.
- Paramedics or emergency medical technicians are also good sources of information, because they may be able to furnish details, such as presence of empty pill bottles.
62
clinical examination in cases of poisoning
63
Examples of drugs causing **Sympathomimetic Toxidrome**
Cocaine.
Amphetamine.
Pseudo-ephedrine.
64
Vital signs in **Sympathomimetic Toxidrome**
Hyperthermia.
Tachycardia.
Hypertension.
Tachypnea.
65
Pupils in **Sympathomimetic Toxidrome**
Mydriasis.
66
Examples of drugs causing **Anticholinergic Toxidrome**
Atropine.
Tricyclis-antidepressant.
Antibistamine,
67
Vital Signs in **Anticholinergic Toxidrome**
Hyperthermia.
Tachycardia.
Hypertension.
68
Pupils in **Anticholinergic Toxidrome**
Mydriasis.
69
Other findings in **Anticholinergic Toxidrome**
Hot, dry, red.
Blind.
Seizures.
70
other findings in **Sympathomimetic toxidrome**
Piloerection.
Hyperreflexia.
Diaphoresis.
Tremors.
71
Examples of Drugs causing **Hallucinogenic Toxidrome**
49-Tetra-Hydrocannabinol.
Phencyclidine.
Lysergic acid diethylamide
72
Vital Signs in **Hallucinogenic Toxidrome**
Tachycardia.
Hypertension.
Tachypnea.
73
Pupils in **Hallucinogenic Toxidrome**
Mydriasis.
Nystagmus
74
Other findings in **Hallucinogenic Toxidrome**
Hallucinations.
Agitation.
Disorientation.
75
Examples of drugs causing **Opiod Toxidrome**
Opiates.
Heroin.
76
Pupils in **Opiod Toxidrome**
Hypothermia
Bradycardia.
Hypotension.
Hypopnea
77
Vital Signs in **Opiod Toxidrome**
Miosis.
78
Other Findings in **Opiod Toxidrome**
CNS depression.
Coma.
Antidote
79
Examples of drugs causing **Sedative-Hypnotic Toxidrome**
Benzodiazepines.
Barbiturates.
Alcohol, Anticonvulsant.
80
Vital Signs in **Sedative-Hypnotic Toxidrome**
Hypothermia
Bradycardia.
Hypotension.
Hypopnea.
81
Pupils in **Sedative-Hypnotic Toxidrome**
Miosis (usually)
82
Examples of Drugs Causing **Cholinergic Toxidrome**
Organophosphates.
Carbamates.
Mushrooms.
83
Other Findings in **Sedative-Hypnotic Toxidrome**
Hyporeflexia.
Confusion.
Stupor.
Coma.
Antidote
84
Vital signs in **Cholinergic Toxidrome**
Hypothermia
Bradycardia.
Tachypnea.
85
Pupils in **Cholinergic Toxidrome**
Miosis.
86
Other Findings in **Cholinergic Toxidrome**
Lacrimation.
Salivation.
Incontinence.
Bronchospasm.
Seizures
**DUMBLES**
87
Causes of **Coma**
- Toxic causes
- Traumatic causes
- Pathologic causes
- Environmental causes
- Hysterical
88
toxic causes of **Coma**
**Generalized CNS depression:**
- (e.g., ethanol, opiates, and sedative-hypnotics).
**Post-ictal phenomenon**
- after a drug-induced seizure: (e.g. anticholinergics).
**Hypoglycemia**
- (e.g., insulin, oral hypoglycomic drugs).
**Cellular hypoxia:**
- (e.g., CO, cyanido).
89
Pathologic causes of **Coma**
- Liver and renal failure.
- Infections as encephalitis or meningitis.
90
Traumatic causes of **Coma**
Head injuries.
91
environmental causes of **Coma**
Hypothermia
Hyperthermia.
92
hysterical causes of **Coma**
No organic cause, normal vital signs, and negative investigations
93
General lines of treatment of **Coma**
- Care of Airway & Breathing
- Coma cocktail
- Control convulsions
- Correct electrolyte, or acid-base disturbance
- CT Scan
94
When is Dextrose given in cases of **Coma**?
- It is given to all patients with depressed consciousness & hypoglycemia.
95
Dose of dextrose in cases of **Coma**
- Child: 25 % (2 ml/kg) IV.
- Adolescent/adult: 50 % (1 ml/kg) IV.
96
When is naloxone given in cases of **Coma**
It is given to all patients with depressed respiration.
97
Dose of Naloxone in cases of **Coma**
- Child: 0.1 mg/kg IV.
- Adolescent/Adult: 0.4 mg IV & 0.1 mg IV "If
suspected Opioid Abuse".
- If no response give up to 2 mg IV.
- If no response, repeat the dose every 2 min. till a total dose of 10 mg.
98
when is Thiamine given in cases of **Coma**?
- It is given to malnourished and chronic alcoholic patients.
99
Dose are thiamine in cases of **Coma**
100 mg IV or IM (is not given routinely lo children).
100
Causes of **Convulsions**
- Toxic causes
- Metabolic Causes
- Traumatic causes
- Pathologic causes
101
Toxic causes of **Convulsions**
- Poisons acting on cerebrum
- Poisons acting on brain stem
- Poisons acting on spinal cord
- Poisons causing cerebral anoxia
102
Poisons acting on cerebrum
- Causing muscular hyperactivity
e.g., amphetamine, cocaine, caffeine and atropine.
103
Poisons acting on spinal cord
Causing tonic convulsions **i.e. sustained hypertonia of the muscles**
- e.g., strychnine.
104
Poisons acting on brainstem
Causing clonic convulsions** i.o., contraction & relaxation of muscles**
- o.g., picrotoxin and lead.
105
Poisons causing cerebral anoxia
cyanide
106
Metabolic causes of convulsions
Hypoglycemia, hyponatremia, hypocalcemia, or hypoxia.
107
Traumatic causes of convulsions
- Head trauma with intracranial injury.
- Idiopathic epilepsy.
- Exertional or environmental hyperthermia
108
Pathological causes of convulsions
- CNS infection (meningitis or encephalitis)
- Febrile seizures in children.
109
General lines of treatment of convulsions
- Maintain an open airway and assist ventilation.
- Use one or more of the following anticonvulsants
- Specific measures
- Consider specific antidotes.
110
Drugs used in cases of convulsions
- Diazepam: 1st Line of therapy:
- Phenobarbitone 2nd Line of therapy:
- Phenytoin: It is not indicated in management of toxic seizures.
111
Specific measures in cases of convulsions
- Glucose for hypoglycemia.
- Cool Immediately for hyperthermia.
- Fluids for dehydration.
112
Types of **Non-Toxic Indigestion**
113
Def of **Non-Toxic Indigestion**
- producing little to no toxicity when ingested in small amounts.
- They are not true poisoning and can be managed by reassurance.
114
Criteria to diagnose non-toxic exposure
**To diagnose a non-toxic exposure; all of the criteria should be present:**
- Absolute identification of the product.
- Absolute assurance that only 1 product was ingested.
- Absence "NO" signal word (Danger, Poison, Warning, Caution) on the container
- A good approximation of the amount ingested.
- Assurance that the victim is free of symptoms.
- Ability to call back at intervals to determine that no symptoms have developed.
115
What causes a patient to be asymptomatic after exposure to toxin?
The patient with exposure to toxin may remain asymptomatic due to:
**Non-toxic substance:** The substance may be nontoxic.
**Insufficient amount:** An insufficient amount has been ingested
**Insufficient absorption:** -An sufficient amount has not been absorbed
116
Investigations in toxocology
**General Investigation "Routine Investigations":**
- ECG
- Lab
- Rad
**Specific Investigation "Toxicological Investigations" "Toxicology Screen"**
117
General lab investigations in toxicology
- Blood Glucose Level.
- Arterial blood gases
- High anion gap metabolic acidosis (MUD PILES)
- Liver function tests: Clotting profile for paracetamol & anticoagulants toxicities.
- Renal functions tests: Urine analysis for rhabdomyolysis
- Complete Blood Picture.
118
**High anion gap metabolic acidosis**
**MUD PILES**
- Methanol
- Uremia
- Diabetic ketoacidosis
- Propylene glycol
- Iron
- Lactic Acidosis
- Ethanol
- Salicylates
119
Radiological Examination in toxicology
- Chest X ray
- Abdominal X ray
120
When is chest x-ray done in toxicology?
If pulmonary edema /aspiration is suspected.
121
What are drugs that causes pneumonitis or pulmonary edema?
**MOPS**
- Meprobamate & Methadone
- Opioids
- Phenobarbital, Propoxyphene, Paraquat & Phosgene
- Salicylates
122
When is abdominal x-ray done in toxicology?
**(BETA CHIP).**
- Barium
- Enteric coated tablets
- Iricyclic antidepressants
- Antihistamines
- Chloral hydrate, Cocaine
- Calcium
- Heavy metals
- lodides
- Phenothiazines, Potassium
123
Samples for toxicology screen
Samples are taken from:
- Blood & Urine "Most Indicated"
- Vomitus, Gastric Lavage & Stool "May Indicated"
124
Value of toxicology screen
The most important evidence of poisoning is by chemical analysis.
125
Categories of toxicology screen
- Blood levels
- Urine screen
- Specific tests
126
Blood levels of 3A & 3I **toxicology screen**
- Alcohols "Ethanol & Mothanol"
- Inotropic "Digoxin & Theophylline"
- Iron
- Analgesic "Paracetamol & Salicylates"
- Anti-Epileptics "Carbamazepine, Phenobarbital"
- Immunosuppressant "Methotrexate"
127
urine screen
In cases of suspected substance of abuse: ABC
- Amphetamine
- Benzodiazepines & Barbiturates
- Cannabis & Cocaine
- Opioids, Tramadol, Pregabalin, & Synthetic Cannabinoids.
128
Specific tests **toxicology screen**
Carboxyhemoglobin levels "if carbon monoxide poisoning is suspected"
129
General lines of treatment of poison patient
130
How to prevent further exposure to the poison?
131
Emergency & supportive treatment
132
What is the greatest contributor to death from drug overdose and poisoning?
Respiratory failure
133
How to maintain Airway opening & clearance?
- Airway opening
- Airway clearance
- Maintain airway opened
134
What maneuver is used for airway opening?
Triple airway maneuver: (Head tilt, jaw thrust, mouth opening)
135
Airway opening if there is any suspicion of neck injury
Place the patient in left lateral position with head downwards which allows tongue to fall forwards and vomitus or secretions to drain out of the mouth.
136
Airway clearance
- Finger sweep technique to remove any F.B. or denture
- Suctioning of the mouth and oropharynx to remove secretions.
137
How to maintain opened airway?
Either by oro or nasopharyngeal airway
138
What are toxic causes of respiratory failure?
**Central Causes:**
- opiates, barbiturates, alcohols.
**Peripheral Causes**
- Airway obstruction
- Neuromuscular block
- Paralysis of respiratory muscles: BOSP
139
Peripheral causes of toxic respiratory failure
- Airway obstruction
- Neuromuscular block
- Paralysis of respiratory muscles: BOSP
140
Central causes of toxic respiratory failure
opiates, barbiturates, alcohols.
Peripheral
141
Toxic causes of airway obstruction
142
What toxins cause Laryngeal spasm?
cyanide poisoning
143
What toxins cause oedema of the airway?
irritant fumes or gas such as chlorine inhalation.
144
What toxins cause bronchospasm?
organophosphates compounds.
145
What toxins cause excessive secretions?
organophosphate or carbamate toxicity.
146
What toxins cause Pneumonia?
- From aspiration of Gastric Contents, or hydrocarbons such as Kerosene.
147
What toxins cause Pulmonary edema?
Organophosphates.
148
What are toxins that caused neuromuscular block?
Neostigmine and physostigmine.
149
Methods of breathing support
- 02 mask (Face mask) or bag valve mask (Ambu bag) or Endotracheal intubation (ETT)
- Pulse oximeter to assess 02 saturation:
150
What are toxins that caused paralysis of respiratory muscles?
**BOSP**
- Botulinum toxins
- Organophosphates
- Snake bites
- Post convulsive muscle exhaustion.
151
What are advantages of endotracheal intubation?
- It protects airway and prevents aspiration and obstruction.
- It allows for mechanically assisted ventilation.
- Some emergency drugs can be given through it e.g., naloxone, atropine and opinophrine.
152
Basics of circularatory support
153
What to do if there is no pulse?
Perform cardiopulmonary resuscitation
154
When to begin continuous ECG monitoring?
This is essential for comatose patients and cardiotoxicity.
155
When is a Foley's catheter introduced?
- It is placed in bladder if patient is seriously ill (shocked, convulsing or comatose).
- Obtain urine for routine and toxicologic testing and measure hourly urine output.
156
Disability assessment
- Once ABC is addressed, neurological status should be assessed, mainly level of consciousness, Pupil, Random blood sugar (RBS).
157
What is **Stupor**?
It is a grade of unconsciousness in which patient can be aroused (awakened) only by painful stimuli.
158
What is **Coma**?
It is a state of prolonged unconsciousness in which patient cannot be aroused by painful stimuli.
159
Levels of consciousness **AVPU Scale**
160
Reed's classification of level of consciousness
161
Types of decontamination
- Skin decontamination
- Eye decontamination
- Lungs decontamination
- GIT Decontamination
162
indications of skin decontamination
**Corrosives:**
- To prevent skin injury.
**Toxins:**
That are readily absorbed through the skin:
- To prevent systemic absorption.
As: Organophosphates Insecticides, Paraquat, Phenol & Oxalic Acid.
163
Steps of skin decontamination
164
Indications of eye decontamination
**Corrosive and Hydrocarbon solvents:**
- That can rapidly damage the cornea.
**Toxins:**
- That are readily skin absorption, can also be absorbed through conjunctiva.
165
Steps of eye decontamination
166
Indications of lung decontamination
**Irritating gases and fumes:**
- As chlorine gas.
**Toxins:**
- That are absorbed through respiratory tract (Inhalation): As CO, Cyanide, Hydrogen Sulphide & Organophosphates Insecticides.
167
Steps of lung decontamination
168
Method of GIT decontamination
- Emesis.
- Cathartics.
- Gastric Lavage.
- Whole Bowel Irrigation.
- Activated Charcoal (Local Antidote).
169
Emesis as a method of decontamination
currently abandoned.
170
Def of **Cathartics**
Substances that enhance passage of materials through the GIT, thus decrease time of contact belween poison and absorptive surface of stomach and intestine.
171
Types of **Cathartics**
- Osmotic Cathartics
- Irritant cathartics
172
examples of **Osmotic cathartics**
Magnesium Sulfate & Sorbitol.
173
MOI of **Osmotic cathartics**
- These are substances that increase osmotic pressure in the intestinal lumen
- Thus causing fluid to be drawn into lumen causing evacuation.
174
Dose of **Osmotic cathartics**
1-2 g/kg "Sorbitol".
175
Examples of **Irritant cathartics**
Castor oil
176
MOI of **Irritant cathartics**
They act by stimulation of motility
177
Dose of **Irritant cathartics**
60-100ml
178
cautions during using of **Irritant cathartics**
- In fat soluble toxic substances because they increase their absorption.
- As yellow phosphorus, CCI4 and chlorinated insecticides.
179
Contraindications of **cathartics**
- GIT hemorrhage.
- Recent bowel surgery.
- Intestinal obstruction and ileus.
- Renal failure for risk of magnesium load.
180
Complications of **cathartics**
- Dehydration particularly in children and elderly
- Electrolyte imbalance.
181
Indications of **Gastric Lavage**
- A significant amount of Ingested Toxic Substance within. 1.hour.
- It is usually used for extremoly toxic substances.
- When patient is unable to protect their own airway, intubate
before proceeding.
182
Procedure of **Gastric Lavage**
- Place large boro orogastric or nasogastric tubo.
- Confirm placement.
- Warm normal saline is instilled in aliquots until stomach contents are clear.
183
Technique of **Whole Bowel Irrigation**
Using a gastric tube, give a surgical bowel-cleansing solution containing a non absorbable polyethylene glycol until rectal effluent is clear.
184
Contraindications of **Gastric Lavage**
In cases of:
- Corrosives
- Sharp objects
- Large pills.
185
Indications of **Whole Bowel Irrigation**
- Ingestion of large dose of iron or lithium or "Other drugs poorly adsorbed to activated charcoal".
- Ingestion of Large amount of sustained release or enteric coated tablets.
- Ingestion of foreign bodies or drug filled packets or condoms.
186
Contraindications of **Whole Bowel Irrigation**
- lleus or intestinal obstruction.
- Comatose or convulsing patient unless airway is protected by endotracheal tube.
187
AE of **Whole Bowel Irrigation**
Nausea, regurgitation and pulmonary aspiration.
188
MOI of **Activated Charcoal**
- Almost irreversibly adsorbs drugs and chemicals, preventing absorption
189
Indications of **Activated Charcoal**
- Consider for all significant toxic ingestions except poorly binds substances "PGAIS"
190
Dose of **Activated Charcoal**
- Give 50 g (adults) or 1 g/kg (children) as a singlo oral doso placed in a cup for self-administration.
- Prepared with a ratio 1:4 charcoal to water
"Goal is to have a charcoal to toxin ratio > 10:1".
- Mixing with ice cream improves palatability for children.
- In intubated patient, AC may be given via oro- or nasogastric tube.
191
Contraindications of **Activated Charcoal**
192
Principle of **Enhanced Elimination**
- It is used in drug intoxication when renal route is a main route to its total clearance.
- Forced diuresis may increase glomerular filtration rato and ion trapping by urinary pH manipulation may enhance elimination of polar drugs.
- It is used in case of healthy kidney,
193
Types of **Enhanced Elimination**
- Urinary Manipulation
- Hemodialysis
- Hemoperfusion
- Hemofiltration
- Peritoneal Dialysis
- Repeated Dose Activated Charcoal (Gut Dialysis)
194
Types of **Urinary Manipulation**
- Urinary alkalization
- Urinary acidification
195
Uses of **Urinary alkalization**
196
Uses of **Urinary acidification**
197
What characters should a toxin have to undergo Hemodialysis?
198
Indications of **Hemodialysis**
199
Why are Drug size, water solubility and protein binding not important limiting factors in cases of hemoperfusion procedure?
Because drug or toxin is in direct contact with adsorbent material
200
Advantages of **Hemoperfusion**
For most drugs, hemoperfusion can achieve greater clearance rates than hemodialysis.
201
Disadvantages of **Hemoperfusion**
Systemic anticoagulation is required, often in higher doses than for hemodialysis and thrombocytopenia is a common complication.
202
Indications of **Hemoperfusion**
203
Principle of **Hemofiltration**
It can remove compounds with large molecular weight through porous membrane.
204
Indications of **Hemofiltration**
205
Advantages of Peritoneal Dialysis
It is easier to perform than hemodialysis or hemoperfusion and does not require anticoagulant.
206
Substances not amenable to significant extracorporeal removal include ......
207
Disadvantages of Peritoneal Dialysis
- However, it can be performed continuously, 24 hours a day,
- 24-hour peritoneal dialysis with dialysate exchange every 1-2 hours is approximately equal to four hours of hemodialysis.
208
Indications of **Repeated Dose Activated Charcoal (Gut Dialysis)**
209
Dose of **Repeated Dose Activated Charcoal (Gut Dialysis)**
210
Route of adminstration of **Repeated Dose Activated Charcoal (Gut Dialysis)**
It is given orally or via gastric tube
211
Types of **Antidotes**
- Antagonists
- Competitors
- Chelators
- Inactivators
212
Principle of action of **Antagonist**
- Substance which antagonizes action of the poison
213
Examples of **Antagonists**
**Atropine**
- antagonizes muscarinic action of organophosphate's insecticides.
**Pilocarpine**
- antagonizes the peripheral action of atropine.
214
Principle of **Competitors**
- A substance which competes with poisons at sites of their action preventing them from exerting their effects.
- They are characterized by having similar chemical formula to poison.
215
Examples of **Narcotic antidotes**
- Naloxone (Narcan, N-ally) oxymorphine)
- Nalmefene (Revex)
- Nallorphine (N-allyl morphine, lethidrone)
216
Examples of **Competitors**
- Narcotic analgesics
- Ethyl Alcohol
217
Characters of **Naloxone (Narcan, N-ally) oxymorphine)**
- It acts as a pure antagonist.
- It is potent with no depressant action on CNS.
- It provides both a therapeutic & diagnostic modality for opioid poisonings.
218
Characters of **Nalmefene (Revex)**
- It acts as a pure antagonist.
219
Characters of **Nallorphine (N-allyl morphine, lethidrone)**
- It acts as agonist-antagonist
220
Characters of Ethyl alcohol as an antidote
- It is the antidote for methanol poisoning.
- It competes with the enzyme alcohol dehydrogenase, → so methanol doses do not change into toxic formaldehyde and formic acid.
221
Principle of **Chelators**
A substance which unites with the absorbed poison forming soluble less toxic and easily excreted complex.
222
Examples of **Chelators**
- All antidotes of heavy metals are chelators
223
Principle of **Inactivators**
A substance which unites with poison to form non-toxic complex
224
Examples of **Inactivators**
**Hydroxocobalamin (Vil. B.12a):** It unites with cyanide forming cyanocobalamin (Vit. B12).
225
Antidote of acetaminophen
N-Acetylcystoine (Mucomyst).
226
Antidote of anticholinergics
**Physostigmine**
Caution: may cause seizures, asystole, cholinergic crisis".
227
Antidote of OCP (Anticholinestrases) & Carbamates
**OCP**
- Atropine
- Pralidoxime
**Carbamates**
- Atropine
228
Antidote of benzodiazepines
Flumazenil
229
Antidote of Beta-adrenergic blockers
Glucagon
230
Antidote of CO toxicity
- Oxygen.
- Hyperbaric O2 in severe cases.
231
Antidote of CCBs
Calcium chloride
Glucagon
232
Antidote of Digitalis
Fab antibodies (Digi-bind).
233
Antidote of Heavy metals
- BAL (dimercaprol), EDTA, Penicillamine, DMSA, Unithiol & DMPS
234
Antidote of Iron
Deferoxamine.
235
Antidote of Methemoglobinemia agents
Methylene blue.
236
Antidote of Methanol & Ethylene glycol
- Ethanol, Folate.
- Fomepizole.
237
Antidote of opiods
Naloxone.
238
# ```
Antidote of warfarin & Super warfarin
Vit. K.
239
Def of the principle **One pill can kill in children**
- Drugs with potential for severe toxicity if one or two tablets ingested by a 10-kg toddler
240
Types of **One pill can kill in children**
241
Cardiac Indications for ICU Admission
- Cardiac arrhythmias.
- QRS duration > 0.12 s.
- Systolic BP < 80 mm Hg.
- Second or third degree atrioventricular block.
- Anticholinergic cardiac toxicity.
242
Indications for ICU Admission
**For All Patients Who Present with Poisoning or Potential Exposure to A Toxic Substance**
- Neurological
- Cardiac
- RESP
- Metabolic & Electrolytes
243
Neurological Indications for ICU Admission
- Toxin-induced seizures
- Unresponsiveness to verbal stimuli or Glasgow coma scale score ≤12.
244
# Respiratory
Respiartory Indications for ICU Admission
- PaCO2 > 45 mm Hg.
- Need for endotracheal intubation
245
Metabolic & Electrolytic Indications for ICU Admission
246
Disposition of intoxicated patients
247
When to transfer the patient
248
we are DONE ✅
🫡
