-Basic Clinical Toxicology

7/30/2019 -Basic Clinical Toxicology

1/21

Basic Principles

1111---- DefinitionDefinitionDefinitionDefinition of poisonof poisonof poisonof poison::::The poison is any substance when introduced into the body, produces toxicity, deleterious effects, ill health up to

death.

2222---- ClassificationClassificationClassificationClassification of poisonof poisonof poisonof poisonssss::::According to site of action:According to site of action:According to site of action:According to site of action:Poisons have local action only:

Examples: Corrosive Poisons

Poisons have remote action only:

Examples: Plant Poisons

Poisons have both local and remote action:

Examples: Irritant Poisons

According to target organ affected:According to target organ affected:According to target organ affected:According to target organ affected:

Neurotoxic poisons:

Examples: alcohol & lead.Cardiotoxic poisons:

Examples: digitalis.

Hepatotoxic poisons:

Examples: ethanol, acetaminophen, phosphorus, carbon tetrachloride and arsenic.Nephrotoxic poisons:

Examples: metals e.g., mercury.

Ohpthalmotoxic poisons:

Examples: UV light (sunlight)

Dermatotoxic poisons:

Examples: UV light, gold & nickel.

Immunotoxic poisons:

Examples: isocyanates.

Poisons affect respiratory tract:

Examples: tobacco smoke, asbestos & ozone.

Poisons affect reproductive System:

Examples: dibromochloropropane.

According to the chemical nature:According to the chemical nature:According to the chemical nature:According to the chemical nature:

Acidic poisons:Examples: sulphuric, nitric and hydrochloric acid.

Alkaline poisons:

Examples:::: caustic soda & caustic potash and ammonium hydroxides

According to the source:According to the source:According to the source:According to the source:

Animal poisons:

Examples: snake bite and scorpion sting

Plant Poisons:

Examples: opium, cannabis, atropine.

According to modeAccording to modeAccording to modeAccording to mode of Poisoning:of Poisoning:of Poisoning:of Poisoning:Deliberate

Overdose as self-harm or suicide attempt.

Child abuse Munchausen's syndrome by proxy.

Third party (attempted homicide, terrorist, warfare).Accidental

Most episodes of pediatric poisoning.

Dosage error.

latrogenic.

Patient error.

Recreational use.

Environmental:

Plants.

Food.

Venomous stings/bites.

Industrial exposures.

According to toxic effectAccording to toxic effectAccording to toxic effectAccording to toxic effect::::

Death: cyanide.

Organ Damage: ozone & lead.

Mutagenesis: UV light.

Carcinogenesis: benzene & asbestos.

Teratogenesis: thalidomide.


2/21

Basic Principles-

3333---- Factors affecting the action of poisonFactors affecting the action of poisonFactors affecting the action of poisonFactors affecting the action of poisonssss::::- Factors related to the poison:

State of the Poison:

Gas form: Gases or vapour poisons are the most rapid action.

Liquid form: Liquid are rapid absorption than solid form.Solid form: Fine powders are rapid than big crystals or lumps.

Dose of the Poison:

The Bigger The Dose The Greater The Toxicity.

Route of the Poison: Method of administration

IIIIV injection: is the Rapidest Route Then

IIIInhalation Then

IIIIM & SC injection Then

IIIIngestion Absorption from m.m. of vagina & rectum is more Then

IIIIntact skin absorption: is the Slowest Route.

- Factor related to the person:

- GGGGastric condition:

AAAAmount of Food:

On Empty Stomach: Poisons have faster action.

On Full Stomach: Poisons have slower action.TTTType of Food:

Fatty Food may:

Absorption of some poisons e.g. Arsenic due to:

Coating the gastric mucosa.

Delaying the gastric emptying

Absorption of other poisons e.g. Phosphorous & DDT due to:

their solubility fat soluble compounds.

- GGGGenetic Condition:

Glaucose 6 phosphate dehydrogenase enzymes Haemolytic effect of some drug Even in

therapeutic doses.

AAAAntimalarial

SSSSulphonamides

VVVVitamin K

NNNNaphthalene

&

BBBBenzene.

3- GGGGeneral condition of the patient:

Generally: Liver, Kidney, Heart diseases Toxicity of most of poisons.

4- Age of the patient:

Generally:

Extremes of age Children & Old age peoples are more susceptible to toxicity.

Example: Children are more susceptible to i action of morphine.

5- Hypersensitivity:

Penicillin:In hypersensitive persons may produce severe symptoms even fatal anaphylaxis by Therapeutic

Dose.

6- Idiosyncrasy:

Morphine:

In abnormal response, it may produce CNS excitation.

7- Tolerance, Habituation and Addiction.

Morphine, Alcohol and Cocaine.

Persons who Tolerated, Habituated or Addicted

To some drugs

Can stand big doses of these drugs without toxicity.

8- Cummulation:

Reach to the effect of single large dose after repeated small doses.

AE: Poor metabolism of the drug e.g.: Digitalis Lead.


3/21

Basic Principles

4444---- General Diagnosis of PoisoningGeneral Diagnosis of PoisoningGeneral Diagnosis of PoisoningGeneral Diagnosis of Poisoning CasesCasesCasesCases:::: Diagnosis of Poisoning: Diagnosis of Poisoning: Diagnosis of Poisoning: Diagnosis of Poisoning:

i- History and circumstantial evidences.

ii- Clinical manifestations.

iii- Investigations.

iiii---- History and circumstantial evidences:History and circumstantial evidences:History and circumstantial evidences:History and circumstantial evidences: Successful treatment of acute toxicity mainly depends on Early Rapid & Correct Diagnosis as i following:

a- Sudden appearance of toxic manifestations in a healthy person or a group of persons after taking certain food ordrink (as food poisoning, methanol and carbon monoxide toxicity).

b- History of intake a poison, financial problems, psychiatric troubles, previous attempts at suicide or threatening by

somebody.

c- Presence of bottle of tablets or insecticide near the victim.

d- Patients rescued from fire (CO, cyanide).

HistoryHistoryHistoryHistory

It should include:

Type of toxin.

Time of exposure (acute versus chronic).

Amount taken.

Route of administration (i.e. ingestion, intravenous, inhalation).

Reason for the ingestion or exposure.It is also important to understand why the exposure occurred (accidental, suicide attempt, euphoria,

therapeutic misadventure)

Presence of history of psychiatric illness or previous suicide attempts.

Patient must be asked, about all drugs taken, including:

Prescription, over-the-counter medications, vitamins, and herbal preparations.

Patients may incorrectly name the drugs they have ingested;

For example, they may refer to ibuprofen as acetaminophen or vice versa.

Patients can be unreliable historians, particularly if:

Suicidal, psychotic, presenting with altered mental status, or under the influence of recreational drugs.

Patient with unreliable history, information taken from family and friends may also prove helpful.


4/21

Basic Principles

iiiiiiii---- Clinical Examination:Clinical Examination:Clinical Examination:Clinical Examination:To detect the symptoms and signs Clinical toxicologyClinical toxicologyClinical toxicologyClinical toxicology

SymptomsSymptomsSymptomsSymptoms:

CNSCNSCNSCNS:

CNS stimulation: AAAAgitation, AAAAnxiety, IIIInsomnia, IIIIrritability, CCCConvulsion & CCCComa. AAIICCAAIICCAAIICCAAIICC

CNS inhibition: DDDDizziness, DDDDrowsiness, SSSStuprous, CCCConfusion & CCCComa. DDSCCDDSCCDDSCCDDSCC

CVSCVSCVSCVS: TTTTachycardia, BBBBradycardia, PPPPalpitation, AAAArrhythmias & AAAArrest. TBPAATBPAATBPAATBPAA

RTRTRTRT: CCCCough, CCCCrepitations, DDDDyspnea, WWWWheeze, & PPPPul. oedema. CCDWPCCDWPCCDWPCCDWP

GITGITGITGIT: AAAAnorexia, NNNNausea, VVVVomiting, AAAAbdominal CCCColic & DiarrheaDiarrheaDiarrheaDiarrhea. ANVAC&DANVAC&DANVAC&DANVAC&D

UTUTUTUT: OOOOliguria, PPPProteinuria, RRRRenal failure, AAAAnuria & HHHHaematuria OPRAHOPRAHOPRAHOPRAH

Signs:Signs:Signs:Signs:

General EGeneral EGeneral EGeneral Examination:xamination:xamination:xamination:

a) Directed cardiovascular, respiratory, abdominal and neurological examination "When patient stabilized".

b) Vital signs, Pulse, Blood Pressure, Respiratory rate, Temp, Pupil, Breath odour, Skin.

Recorded in initial evaluation & repeated regularly.

c) Temperature:

Hypothermia (phenothiazines, barbiturates, or tricyclics) or

hyperthermia (amphetamines, Ecstasy, MAOls, cocaine, antimuscarinics, theophylline, serotonin syndrome).

d) Muscle rigidity:

(Ecstasy, amphetamines).

e) Skin:

Cyanosis (methaemoalobinaemiay ) very

Pink (carboxyhaemoglobinaemia, cyanide, hydrogen sulphide)

Blisters (barbiturates, TCAs, benzodiazepines)

Needle tracks; hot/flushed (anticholinergics).

f) Breath:

ketones (diabetic/alcoholic ketoacidosis)

Bitter almonds (cyanide)

Garlic-like (organophosphates, arsenic)

Rotten eggs (hydrogen sulphide) organic solvents.

g) Mouth:

Perioral acneiform lesions (solvent abuse)

Dry mouth (anticholinergics)

Hypersalivation (parasympathomimetics).

RespiraRespiraRespiraRespiratorytorytorytory systemsystemsystemsystem, abdomen, CNS, urine color, abdomen, CNS, urine color, abdomen, CNS, urine color, abdomen, CNS, urine color:::: see later


5/21

Basic Principles

iiiiiiiiiiii---- InvestigationsInvestigationsInvestigationsInvestigations::::They are done to assess base line of the patient and follow up target organs.

Treat the patient and not the poison is fact still present up till now .

History & clinical examination are the main step in the diagnosis of toxicological cases .

aaaa---- Routine investigations:Routine investigations:Routine investigations:Routine investigations: ECG

U+E, lab glucose, anion gap /lactate & osmolal gap.

LFT & Clotting (Paracetamol, anticoagulants).

Arterial Blood Gases.

Urinalysis - ? Rhabdomyolysis, save sample for possible Toxicological analysis.

CXR if pulmonary oedema/aspiration suspected.

Common radiopague medications: (BETA CHIP)Common radiopague medications: (BETA CHIP)Common radiopague medications: (BETA CHIP)Common radiopague medications: (BETA CHIP)

Barium

Enteric coated tablets

Tricyclic antidepressants

Antihistamines.

Chloral hydrate, cocaine, calcium, condoms (contains tablets).

Heavy metals

Iodides

Phenothiazines, potassium

Chest filmsChest filmsChest filmsChest films::::

Drugs causing pneumonitis or pulmonary edema (MOPSMOPSMOPSMOPS)

MMMMeprpbamate

MMMMethadone

OOOOpioids

PPPPhenobarbital

PPPPropoxyphene

PPPParaquat

PPPPhosgene

SSSSalicylates

bbbb---- ChemChemChemChemical detection: (Analytical toxicology)ical detection: (Analytical toxicology)ical detection: (Analytical toxicology)ical detection: (Analytical toxicology) The most important evidence of poisoning is by chemical analysis.

Samples are taken from vomitus, gastric lavage, blood, urine and stool.

Toxicological laboratory screenscreenscreenscreen is important in

(Come , Convulsion , Acute De(Come , Convulsion , Acute De(Come , Convulsion , Acute De(Come , Convulsion , Acute Delirium , Metabolic Acidosis & Hypoxia)lirium , Metabolic Acidosis & Hypoxia)lirium , Metabolic Acidosis & Hypoxia)lirium , Metabolic Acidosis & Hypoxia)

Toxicological Laboratory serum levelserum levelserum levelserum level is important in :-

(Alcohol(Alcohol(Alcohol(Alcohol AspirinAspirinAspirinAspirin ParacetamolParacetamolParacetamolParacetamol DigoxinDigoxinDigoxinDigoxin IronIronIronIron TheophylineTheophylineTheophylineTheophyline salicylatessalicylatessalicylatessalicylates ---- lithium antilithium antilithium antilithium anti----epileptics )epileptics )epileptics )epileptics )

Toxicological Laboratory urine drug screen

(is the(is the(is the(is the sample of choice for the most of the drugs and metabolites)sample of choice for the most of the drugs and metabolites)sample of choice for the most of the drugs and metabolites)sample of choice for the most of the drugs and metabolites)

(Athletes(Athletes(Athletes(Athletes Brain DeathBrain DeathBrain DeathBrain Death Pregnancy suspect abusePregnancy suspect abusePregnancy suspect abusePregnancy suspect abuse TTT Abuse ProgramTTT Abuse ProgramTTT Abuse ProgramTTT Abuse Program Work Place)Work Place)Work Place)Work Place)

Carboxyhaemoglobin levels if carbon monoxide poisoning is suspected.

Comprehensive toxicology screens are not normally indicated in the emergency treatment.


6/21

Basic Principles

5555---- General Treatment of Poisoning Cases:General Treatment of Poisoning Cases:General Treatment of Poisoning Cases:General Treatment of Poisoning Cases:

General lines of treatment of poisoned patientGeneral lines of treatment of poisoned patientGeneral lines of treatment of poisoned patientGeneral lines of treatment of poisoned patient

Good supportive care is the backbone of any successful therapy of poisoned patients.

1. Stop exposure and Emergency treatment.

2. Decontamination.

3. Excretion Enhancement.

4. Antidote Administration.

5. Symptomatic treatment.

IIII---- Stop Exposure and Emergency Treatment:Stop Exposure and Emergency Treatment:Stop Exposure and Emergency Treatment:Stop Exposure and Emergency Treatment:iiii---- Stop Exposure:Stop Exposure:Stop Exposure:Stop Exposure:Aim to prevent further exposure or administration of poisons:Aim to prevent further exposure or administration of poisons:Aim to prevent further exposure or administration of poisons:Aim to prevent further exposure or administration of poisons:

In Medical Treated Patient.

If toxic S & S of any drug appear stop i drug immediately.

In Industrial or Agricultural workers:

Removed from the polluted area.

In Homicidal or Suicidal Cases:

Hospitalization and observation to prevent further exposure.

In Children:

Any drugs must be kept away from children to avoid accidental intake.

iiiiiiii---- Emergency treatment:Emergency treatment:Emergency treatment:Emergency treatment:The clinical approach to the poisoned patient starts with recognition & treatment of life threatening condition A, B, C & D.

AAAAirway:

Airway Opening & Clearance;Airway Opening & Clearance;Airway Opening & Clearance;Airway Opening & Clearance;

The greatest contributor to death from drug overdose or poisoning is respiratory failure.

Airway opening:Airway opening:Airway opening:Airway opening:

Triple airway maneuver: (Head tilt, jaw thrust, Mouth opening)

If there is any suspicion of neck injury:

Place the patient in left lateral position with the head downwards which allows the tongue to fail forwards andvomitus or secretions to drain out of the mouth.

Airway clearance:Airway clearance:Airway clearance:Airway clearance:

Finger sweep technique to remove any F.B. or denture.

Suctioning of the mouth and oropharynx to remove secretions.

ToxicToxicToxicToxic causes of respiratory failure;causes of respiratory failure;causes of respiratory failure;causes of respiratory failure;

I- Central causes:

Such as opiates, barbiturates, alcohols .....

II- Peripheral causes:

1- Airway obstruction

2- Neuromyscular block

3- Paralysis of respiratory muscles

((((1111)))) Airway Obstruction:Airway Obstruction:Airway Obstruction:Airway Obstruction:

Falling back of the tongue or vomitus in a patient with altered mental status such as in:Toxic comatose patient.

Excessive secretions as in:

Organophosphate or carbamate toxicity.

Edema of the airway:

Irritant fumes or gas such as chlorine inhalation.

Laryngeal spasm as in:

Cyanide poisoning.

Bronchospasm as in:

Organophosphorus compounds.

Pneumonia as in:

Aspiration of gastric contents, or aspiration of hydrocarbons such as kerosene.

Pulmonary edema as in:

Organophosphate.

((((2222)))) NeuromuscuIar block:NeuromuscuIar block:NeuromuscuIar block:NeuromuscuIar block:

Neostigmine and physostigmine.

((((3333)))) Paralysis of respiratory muscles:Paralysis of respiratory muscles:Paralysis of respiratory muscles:Paralysis of respiratory muscles: BOSBBOSBBOSBBOSB

BBBBotulinum toxins. "

OOOOrganophosphates.

SSSSnake bites.

PPPPost convulsive muscle exhaustion.


7/21

Basic Principles

BBBBreathing support:(I) Airway devices:(I) Airway devices:(I) Airway devices:(I) Airway devices:

Oropharyngeal or nasopharyngeal airway devices:Oropharyngeal or nasopharyngeal airway devices:Oropharyngeal or nasopharyngeal airway devices:Oropharyngeal or nasopharyngeal airway devices:

Placed in the mouth or nose to lift the tongue and push it forward.

Endotracheal intubation (ETT):Endotracheal intubation (ETT):Endotracheal intubation (ETT):Endotracheal intubation (ETT):In comatose patient....

Advantages::::

It protects the airway & prevents aspiration and obstruction.It allows for mechanically-assisted ventilation.

It allows some emergency drugs to be be given through it e.g. naloxone, atropine and epinephrine

Cricothyrodotomy or tracheostomy:Cricothyrodotomy or tracheostomy:Cricothyrodotomy or tracheostomy:Cricothyrodotomy or tracheostomy:In upper airway obstruction (ETT can not be inserted).

(II)(II)(II)(II) Assist ventilation: (oxygen)Assist ventilation: (oxygen)Assist ventilation: (oxygen)Assist ventilation: (oxygen)

IndicationIndicationIndicationIndication:

PO2 < 60 mmHg & PCO2 > 60 mmHg.

Don't wait until the patient is apneic

Methods: Methods: Methods: Methods:

Mouth-to-mouth ventilation.

Mouth-to-mask ventilation (this method is more hygienic).

Bag and mask ventilation.

Bag and tube ventilation.Mechanical ventilation (used when resuscitative efforts are prolonged).

(III(III(III(III)))) Active treatment:Active treatment:Active treatment:Active treatment:

Bronchospasm:Bronchospasm:Bronchospasm:Bronchospasm:Administer bronchodilators if there is wheezing or ronchi.

B2-agonists e.g. sulbutamol inhalation.

Aminophylline slowly IV if the above is not effective.

Pneumonia:Pneumonia:Pneumonia:Pneumonia:

Antibiotics if there is evidence of infection.

Corticosteroids (if it is a chemical-induced pneumonia).

Pulmonary edema:Pulmonary edema:Pulmonary edema:Pulmonary edema:

Avoid excessive fluid administration.

Administer supplemental oxygen.Diuretics.

Specific antidote:Specific antidote:Specific antidote:Specific antidote:

Consider specific antidotes:

e.g. Naloxone can reverse respiratory depression in a patient with opiate overdose.

CCCCirculatory support :( 5)(I)(I)(I)(I) CheckCheckCheckCheck blood pressure, pulse rate and rhythm:blood pressure, pulse rate and rhythm:blood pressure, pulse rate and rhythm:blood pressure, pulse rate and rhythm:

- Perform cardiopulmonary resuscitation if there is no pulse.

- Treat shock and arrhythmia if present.

(II)(II)(II)(II) BeginBeginBeginBegin continuouscontinuouscontinuouscontinuous ECG monitoring:ECG monitoring:ECG monitoring:ECG monitoring:

- This is essential for comatose patients and cardiotoxicity.

(III)(III)(III)(III) EstablishEstablishEstablishEstablish an intravenous line.an intravenous line.an intravenous line.an intravenous line.

(IV)(IV)(IV)(IV) DrawDrawDrawDraw blood for routine studies.blood for routine studies.blood for routine studies.blood for routine studies.

(V)(V)(V)(V) InsertInsertInsertInsert Foley's catheterFoley's catheterFoley's catheterFoley's catheter

- It is placed in the bladder if the patient is seriously ill (shocked, convulsing or comatose).

- Obtain urine for routine and toxicological testing and measure hourly urine output.


8/21

Basic Principles

DDDDisability:Once ABC are addressed, the neurological status should be assessed, mainly level of consciousness & convulsions.

IIII---- level oflevel oflevel oflevel of consciousnessconsciousnessconsciousnessconsciousness:Stupor or coma

Stupor: it is a grade of unconsciousness in which the patient can be aroused (awakened) only by painful stimuli.

Coma: it is a state of prolonged unconsciousness in which the patient can not be aroused by painful stimuli.

Coma:Coma:Coma:Coma:

i- Definition: It is a state of unconsciousness.

ii- Aetiology and types:

1) Toxic causes:

Generalized CNS depression

(e.g. ethanol, opiates, sedative-hypnotic)

As a post-ictal phenomenon

(after a drug-induced seizure) (e.g. anticholinergics).

Hypoglycemia

(e.g. insulin, oral hypoglycemic drugs).

Cellular hypoxia

(e.g. CO, cyanide).

2) Traumatic causes:

Head injures.3) Pathologic causes:

Liver & renal failure.

Infections as encephalitis or meningitis .4) Environmental causes:

Hypothermia or hyperthermia.

5) Hysterical:

Normal vital signs: Pulse, B/P, Temperature & Respiratory Rate.

No apparent organic lesion.

No characteristic odour.

No positive finding investigation "Negative Analysis".

Not complete coma.

iii- Complications of coma:

Loss of protective airway reflexes, resulting in airway compromise which is a major cause of death.

Hypotension.

Hypothermia.

Rhabdomyolysis.iv- Grades:

Level of consciousness is evaluated roughly by:AVPUAVPUAVPUAVPU ScaleScaleScaleScale:

AAAA= AAAAlert.

VVVV= Drowsy but VVVVerbal command responsive.

PPPP= Comatose but response to Pain responsive.

UUUU= Comatose and totally UUUUnresponsive.

Reed'sReed'sReed'sReed's ScaleScaleScaleScale::::

GGGG0000:::: Asleep.

GI:GI:GI:GI: Response to verbal command & Drowsy.

GII:GII:GII:GII: Unresponsive to verbal command but minimal responsive to pain.

GIII:GIII:GIII:GIII: Unresponsive to verbal command & to pain with absent reflex.

GIV:GIV:GIV:GIV: Completely unresponsive with cyanosis and shock.

StageStageStageStage Conscious levelConscious levelConscious levelConscious level Pain responsePain responsePain responsePain response ReflexesReflexesReflexesReflexes RespirationRespirationRespirationRespiration CirculationCirculationCirculationCirculation

0000 Asleep Arousable Intact Normal NormalIIII Comatose Withdrawal Intact Normal Normal

IIIIIIII Comatose Non Intact Normal Normal

IIIIIIIIIIII Comatose Non Absent Normal Normal

IVIVIVIV Comatose Non Absent Cyanosed Shock

Glass Gaw Coma Scale:Glass Gaw Coma Scale:Glass Gaw Coma Scale:Glass Gaw Coma Scale:

Depend on Eye signs Response to painful stimuli Response to verbal command.The best score "15" The worst score "3" Frank coma "


9/21

Basic Principles

iii- Antidotes:

Give coma Cocktail:

DDDDextrose, NNNNaloxone and TTTThiamine:

DDDDextrose:

- It is given to all patients with depressed consciousness.

- It is given To treat or exclude hypoglycaemia"

- Child: 25 % (2 ml/kg) I.V.

- Adolescent/Adult: 50 % (1 ml/kg) I.V.

NNNNaloxone:

- It is given to all "adult and children" patients with depressed respiration "Respiratory failure"

- Child: 0.1 mg/kg I.V.

- Adolescent/Adult: 0.4 mg I.V.- If no response give 2 mg I.V.

- If no response, repeat the dose every 2 min. till a total dose of 10 mg

TTTThiamine:

- It is given to malnourished and chronic alcoholic patients.

- It is not given routinely to children.

- 100 mg l.V. or I.M.

Specific Antidote is given according to the type of toxicity.

iv- Elimination Enhancement: According to the type of toxicity.

v- Symptomatic treatment:

BBBBuccal care: Frequent wash the mouth.

BBBBreathing care: Oxygen inhalation and frequent suctioning, antibioticsBBBBladder care: Catheterization under aseptic condition.

BBBBowel care: Frequent enema, antacid and lactulose.

BBBBed sores: Frequent changing of the patient position in bed to avoid bedsores.

CCCControl convulsions if they are present.

CCCCorrect acid-base disturbance.

CCCCare of the eyes: Antibiotic eye drops & ointment and covering.

CCCConsider specific antidotes e.g. flumazenil for benzodiazepines

CCCCT scan and treat accordingly if suspecting a brain lesion

.&...&...&...&..

AAAAntibiotic: to avoid the infection Prophylactic

BBBBlanket: to treat hypothermia.

CCCContinuous monitoring: of pulse, B/P, temperature & respiratory rate.

DDDDehydration: treated by IV fluids.EEEElectrolytes correction & fluid balance

FFFFeeding: Ryles tube for nutritional support.


10/21

Basic Principles

2222---- Convulsions:Convulsions:Convulsions:Convulsions:1- Causes:

1) Toxic causes:

Poisons acting on the cerebrum "muscular hyperactivity":

e.g. Amphetamine, cocaine, caffeine & atropine.

Poisons acting on the brain stem "clonic convulsions" i.e. contraction and relaxation of the muscles:

e.g. Picrotoxin & Pb.

Poisons acting on the spinal cord "tonic convulsions" i.e. sustained hypertonia of the muscles.:

e.g. StrychninePoisons cerebral anoxia:

e.g. Cyanide

2) Metabolic causes:

Hypoglycemia, hyponatremia, hypocalcemia, or hypoxia.

3) Traumatic causes:

Head trauma with intracraniaLmjury.

4) Idiopathic epilepsy.

5) Exertional or environmental hyperthermia.

6) Pathologic causes:

- CNS infection: meningitis or encephalitis, febrile seizures in children.

2- Complications:

Any seizures can cause:

Airway compromise, resulting in apnea or pulmonary aspiration.

Multiple or prolonged seizures:

May cause severe metabolic acidosis, hyperthermia, rhabdpmyolysis, and brain damage.

3- Treatment of convulsions:

i- Emergency treatment:

Maintain an open airway and assist ventilation

Put the patient in Dark Quite Room to avoid any stimulation

ii- Decontamination:

Emesis: X is contraindicated to avoid precipitating the convulsion

Gastric lavage: X is contraindicated to avoid precipitating the convulsion

iii- Antidotes:

According to the toxicity type.iv- Enhancement of Elimination:

According to the toxicity type.

v- Symptomatic treatment:

CCCConvulsion control BY:

Use one or more of the following anticonvulsants

Anticonvulsant Drugs:

Benzodiazepines:

Djazepam: 0.1- 0.2mg/kg IV "10 mg for Adult .2mg/kg for Children"

Midazolam: 0.1- 0.2mg/kg IM when IV access is difficult

Barbiturates:

Ultrashort acting as pentothal sodium: 0.5 -1 gm, slowly IV

Short acting barbiturates: 0.5 -1 gm, slowly IV

Phenobarbital: 10-15mg/kg slowly IV infusion over 15-20 minutes.

Phenytoin:

the anticonvulsant of last choice for most drug-induced seizures.DDDDehydration: Fluids.

EEEExhaustion: Bed rest.

FFFFever: Cold sponges.

GGGGlaucose: in cases of hypoglycaemia


11/21

Basic Principles

IIIIIIII---- Decontamination:Decontamination:Decontamination:Decontamination:

iiii---- Skin Decontamination:Skin Decontamination:Skin Decontamination:Skin Decontamination:

IndicatiIndicatiIndicatiIndications:ons:ons:ons:i- Cases of Corrosives to prevent skin injury.

ii- Toxins that are readily absorbed through the skin

(e.g. organophosphorous insecticides, paraquat, phenol, oxalic acid, etc) to prevent systemic absorption.

Steps of decontamination:Steps of decontamination:Steps of decontamination:Steps of decontamination:Wear protective clothes & gloves.

Remove the patient's contaminated clothing.

Flush exposed areas with copious quantities of tepid water or saline for at least 30 minutes.

Use soap for oily substances.

iiiiiiii---- Eye decontamination:Eye decontamination:Eye decontamination:Eye decontamination:

Indications:Indications:Indications:Indications:

i- Corrosive agents and hydrocarbon solvents that can rapidly damage the cornea.

ii- Toxins that are readily absorbed through the skin can also be absorbed through the conjunctiva.

SteSteSteSteps of decontamination:ps of decontamination:ps of decontamination:ps of decontamination:Remove the contact lens.

Flush exposed eyes with copious quantities of tepid water or saline for up to 20 minutes.

Consult ophthalmologist after irrigation.

iiiiiiiiiiii---- Lungs (inhalation)Lungs (inhalation)Lungs (inhalation)Lungs (inhalation)

Indications:Indications:Indications:Indications:

1. Irritating gases and fumes e.g. chlorine gas.2. Toxins that are absorbed through the respiratory tract

e.g. CO, cyanide, hydrogen sulphide, organophorous insecticides.

Steps of decontamination: Steps of decontamination: Steps of decontamination: Steps of decontamination:

Ensure adequate respiratory protection for yourself and other care providers (wear protective mask).

Remove the victim from exposure to fresh air.

Care of respiration is started after cleaning the mouth:

Administer humidified O2 (if available) and assist ventilation (if necessary), Tracheostomy or ETT may be needed.

Observe for evidence of upper respiratory edema:

(Early manifested by stridor and hoarse voice)

(Later manifested by non-cardiogenic pulmonary edema "dyspnea, tachypnea and hypoxemia").


12/21

Basic Principles

iviviviv---- Gastric Decontamination:Gastric Decontamination:Gastric Decontamination:Gastric Decontamination:

iviviviv---- GIT decontamination:GIT decontamination:GIT decontamination:GIT decontamination:

1. Emesis.

2. Gastric lavage.

3. Local antidotes e.g. activated charcoal.

4. Cathartics.

5. Whole bowel irrigation.

aaaa---- EEEEmesis:mesis:mesis:mesis:

i- Definition:

A very rapid and safe method of decontamination.

This is one of the most convenient methods used to get rid of the poison from the stomach.

ii- Types:

Systemic: apomorphine is unsafe and should not be used.

Mechanical: By: Tongue depressor.

Chemical: By: Syrup of Ipecac.

1- Definition:

Most safest Method for induction of emesis

Ipecac is the dried root of Cephalus ipecaquanha plant that contains the active alkaloidsemetine & cephaline.

Syrup of ipecac is the emetic of choice in both children over the age of 6 months and in adults.

2 -Indications: Large Amount of Poisons Ingested Within 1 Hour, after 60 minutes it is not effective.3- Contraindication:

PoisonPoisonPoisonPoison::::

Convulsants

Corossives (inorganic).

Carbon (Hydrocarbons)

Sharp objects (needle, pin)

PatientsPatientsPatientsPatients::::

Comatose patient or Unconscious

Come late. >1 hour.

Children


13/21

Basic Principles

2222---- Gastric Lavage:Gastric Lavage:Gastric Lavage:Gastric Lavage: Stomach Wash

i- Definition:

It is the most satisfactory method to remove the poison from the stomach:

ii- Indications:

It is usually used for extremely toxic substances.

In cases of unknown ingestions or when loss of consciousness is present

Recently, the gastric lavage is onlyonlyonlyonly indicated if:

Large Amount Life threatening of Poisons Ingested Within 1 Hour.

iii- Contraindications:

Absolute contraindications:Corrosives:Corrosives:Corrosives:Corrosives: Mineral Acids & Alkalies: to Avoid Gastric Perforation.

Relative contraindications:

G.L. can be done with some precautions

Convulsions:Convulsions:Convulsions:Convulsions:

Gastric Lavage is contraindicated EXCEPT:

After general anesthesia To avoid induction of another fit.

Coma:Coma:Coma:Coma:


After endotracheal intubation To avoid aspiration pneumonia.

CarbonCarbonCarbonCarbon HydrocarbonHydrocarbonHydrocarbonHydrocarbon Kerosene & other Petroleum Distillate


After cuffed endotracheal intubation In Large Ingestion - To avoid aspiration pneumonia.Come lateCome lateCome lateCome late after lapse of 1 hours from ingestion.

Except in poisoning delayed gastric Emptying

CasesCasesCasesCases of oesophageal varices & bleeding tendencyof oesophageal varices & bleeding tendencyof oesophageal varices & bleeding tendencyof oesophageal varices & bleeding tendency:

Must be take good history

v- Technique:

1- Positioning:

Place the patient on one side: "Better the left side"

Put the head at a level lower than the feet "Avoid regurgitation"

Remove any denture.

2- Introduction of the stomach tube:

AAAApply liquid paraffin to i lower end of Place large bore OG/NG tube (16-36 Fr) as a lubricant

Then, introduce the tube over the tongue.

AAAAsk the patient to swallow if conscious this make the passage more easily

Until the mark reaches the level of the lip.AAAAssure that the tube in the stomach by:

In conscious patient:In conscious patient:In conscious patient:In conscious patient:

If the tube passes into the air passage.Sudden spasmodic attack of

Cough, Cyanosis, Chest Pain & Dyspnoea

In unconscious patient:In unconscious patient:In unconscious patient:In unconscious patient: Semiconscious or Comatose

Cough reflex is lostis lostis lostis lost and so the tube may pass into the trachea without cough reflex so:

Ensure by the Following Tests:

If the tube passes into the STOMACHSTOMACHSTOMACHSTOMACH

Aspirated gastric content:Aspirated gastric content:Aspirated gastric content:Aspirated gastric content: See: gastric content by aspiration

Bubbling soundsBubbling soundsBubbling soundsBubbling sounds heared sound stethoscope on the epigastrium when little air injected via the tube.

3- Suction:

Aspirate as much as possible - Put a sample in a clean jar- Send it to laboratory

4- Lavage:

Instillate: 200 ml of tap water and aspirate it until withdrawal fluidclear & odourless or 2 liters used

Inject: Activated charcoal & cathartic 60 gm is given.

5- Extraction

After tight closure of the proximal end of the tube to avoid escape of the fluid from the distal end to the

trachea during withdrawal .

vi- Complication:

LLLLaryngeal spasm (Procedure very irritant to ptn.) may produce cyanosis.

AAAAspirated pneumonia.

VVVVigorous maneuvers Epistaxis.

AAAArrhythmia & Electrolytes Imbalance.

GGGGIT injury & Giddiness & other CNS manifestations due to hyponatriaemia.

EEEEnhancement the passage of the poison to the intestine .

N.B.

Emesis is better in (Sustained release tablets) & (large masses of tablets).Gastric lavage is better in (coma) & (Hydrocarbon).


14/21

Basic Principles

3333---- Activated Charcoal:Activated Charcoal:Activated Charcoal:Activated Charcoal:

i- Definition: It is a substance that almost irreversibility adsorbs drugs and chemicals, preventing absorption.

ii- Mechanism: ActivatedActivatedActivatedActivated charcoal adsorbs most of the toxins.charcoal adsorbs most of the toxins.charcoal adsorbs most of the toxins.charcoal adsorbs most of the toxins.

iii- Indications:

Single doseSingle doseSingle doseSingle dose indicationindicationindicationindication::::

Agents responsive to multiple dose activated charcoal

Substance adsorbable by activated charcoal (ABCD)(ABCD)(ABCD)(ABCD)

AAAAminophylline (teophyllin), AAAAntimalarials (quinine),

BBBBarbiturates (Phenobarbital)

CCCCarbamazepine

DDDDapsone

Substance not adsorbable by activated charcoal (PH(PH(PH(PHAAAAILS)ILS)ILS)ILS)PPPPesticides, Potassium

HHHHydrocarbons

AAAAcids & AAAAlkali "Corrosives" - "Poor bind and Difficult Endoscopy" AAAAlcohols

IIIIron, IIIInsecticides

LLLLithium

SSSSolvents: "Petroleum Distillates" &

Multiple doses:Multiple doses:Multiple doses:Multiple doses:

1- Drug Excreted in The Bile

(Phenobarbital(Phenobarbital(Phenobarbital(Phenobarbital PhenytoinPhenytoinPhenytoinPhenytoin CabamezapineCabamezapineCabamezapineCabamezapine Salicylates & Theophyline)Salicylates & Theophyline)Salicylates & Theophyline)Salicylates & Theophyline)

2- Drug Excreted in The Intestine:

(Digoxin(Digoxin(Digoxin(Digoxin Morphine)Morphine)Morphine)Morphine)3- Drugs form Concretion :

(Salicylate & Barbiturates)(Salicylate & Barbiturates)(Salicylate & Barbiturates)(Salicylate & Barbiturates)

4- Drugs Inhibit GIT motility:

(Morphine & Anticholinergic)(Morphine & Anticholinergic)(Morphine & Anticholinergic)(Morphine & Anticholinergic)

5- Drugs of Sustained Release Tablets:

(Theophyline & NSAI)(Theophyline & NSAI)(Theophyline & NSAI)(Theophyline & NSAI)

The activated charcoal is the best method to decrease amount of the drug absorption in the patient which may

reach to 50 % if given in the 1st hour in ratio (10:1) (charcoal : toxins) amount.

The main goal is to have a charcoal to toxin ratio > 10:1

iii- Route: Oral

iv- Dose:

Single Dose Activated Charcoal:

For children: 30-60 gm I gm/kg of body weightFor Adult: 60-100 gm in adult

Shaken in 200 ml of water or prepared as slurry with a ratio 1:4 charcoal to water.

Multiple Doses Activated Charcoal: MDAC50 gm every 4-6 hrs & not exceed 300 gm.

Given orally or by Ryles followed by cathartic.

Cathartic Dose:

Cathartics such as sorbitol ( 5ml/kg) can be used with first dose of charcoal to prevent constipation.

Cathartics should not be used repetitively as they will cause fluid and electrolytes disturbances.


15/21

Basic Principles

4444---- Cathartics:Cathartics:Cathartics:Cathartics:

1- Definition:

It is a substance stimulates the Gastro intestinal tract motility.

2- Mechanism:

The cathartics substances enhance the passage of materials through the GIT thus decrease the time of contact

between the poison and the absorptive surface of the stomach and intestine

If given with charcoal, it will speed of charcoal in the intestine with more substance adsorbed by it. So it decreasesthe transient time (charcoaltoxins) complex before desorption occur

3- Indication: Single Dose Cathartic is not harmful .

4- Contraindication:

HHHHaemorrhage.

AAAAcid & Alkalie,

RRRRenal Failure "For Risk of Mg Over Load" - RRRRecent Bowel Surgery

IIIIntestinal obstruction and Ileus

DDDDiarrhea

EEEExtreme of Ages

It should be avoided in fat soluble poisons as organophosphates or carbon tetrachloride.

5- Complication:

DDDDehydration particularly in children and elderly

EEEElectrolyte imbalance e.g. magnesium sulphate at a dose of 15-30 gm in a glass of water

6- Types:

Osmotic: (Sorbitol)

These are substances that increase the osmotic pressure in the intestinal lumen, thus causing fluid to be drawn

into the lumen causing evacuation.

Bulk Forming: (cellulose)

Irritant (Castor Oil)

They act by stimulation of motility such as castor oil at a dose 60-100ml

Coating (Olive Oil)

5555---- Whole bowel irrigation:Whole bowel irrigation:Whole bowel irrigation:Whole bowel irrigation:1- Definition::::

It is a procedure stimulate or hurry the passage of Gastro-intestinal content.

2- Mechanism:

It is Using a gastric tube, give a surgical bowel-cleansing solution containing a non-absorbable polyethylene glycol in abalanced electrolyte solution, (formulated to pats through the intestinal tract without being absorbed)

3- Dose:

Dose: 2L/h (children: 500 mi/h), until rectal effluent is clear.

Activated charcoal 25-50 g /2-3 h may be administered while; whole bowel irrigation is proceeding, if the ingested drug is

adsorbed by charcoal.

Stop administration after 8-10 L (children: 150-200 mi/kg) if no rectal effluent has appeared.

4- Indications::::

Large ingestion of the dose of iron or lithium or other drugs poorly adsorbed to activated charcoal.

Large ingestion of sustained release or enteric coated tablets.

Body Baker "Drugs filled packets or condoms"

Body Stuffer

Foreign body ingestion

5- Contraindications:

IIIIleus

IIIIntestinal obstruction.

CCCComatose patient the airway is protected

CCCConvulsing patient unless the airway is protected.

6- Adverse effects:

NNNNausea

VVVVomiting

BBBBloating

PPPPulmonary aspiration

& Less effective activated charcoal when given with whole bowel irrigation


16/21

Basic Principles

IIIIIIIIIIII---- Antidote TherapyAntidote TherapyAntidote TherapyAntidote Therapy:::: "See L"See L"See L"See Later"ater"ater"ater"

IVIVIVIV---- EnhancedEnhancedEnhancedEnhanced EEEElimination:limination:limination:limination:

Toxic substances and metabolites are excreted from the body by different ways:

Lung, Liver, Intestine & Kidney.

The aim of this process is:

IncreaseThe effectiveness of the excretory routes that lead to:Decreasethe half-life of the toxic substances.Decreasethe duration and severity of the toxic substances.

It is used in drug intoxication when the renal route is a significant contributor to its total clearance.

Forced diuresis may increase glomerular filtration rate.

Urinary pH manipulation may produce ion trapping by may induce elimination of polar drugs.

Via Lung:

Rate of excretion in Expired Air:Expired Air:Expired Air:Expired Air:

By inhalation of oxygen 95% O2

Rate & Depth of Respiration.

Via Liver:

Rate of excretion in Bile:in Bile:in Bile:in Bile:

By Hepatotonic drugs e.g. vit. C & amino acids

Rate of Hepatic Metabolism i.e. Detoxification Power.Via Intestine:

Rate of excretion in stool:in stool:in stool:in stool:

By Purgatives

Rate of peristaltic movement

Via Kidney:

Rate of excretion in urine: MAIN RMAIN RMAIN RMAIN ROUTEOUTEOUTEOUTE

The elimination enhancement via kidney through urine will depend on:

The kidney functions are Normal or Impaired.

iiii---- Fluid Diuresis:Fluid Diuresis:Fluid Diuresis:Fluid Diuresis:

iiiiiiii---- Diuretics:Diuretics:Diuretics:Diuretics:

iiiiiiiiiiii---- Urinary manipulation and forced dUrinary manipulation and forced dUrinary manipulation and forced dUrinary manipulation and forced diuresis:iuresis:iuresis:iuresis:I- Definition:

It is the simplest method to excretion of some poisons

By Renal Excretion G.F.R. of these poisons

Renal Clearance of the poison

By alternating the urine pH according to acidity or alkalinity of the drugs

More Renal Clearance of the poison.

II- Types:

A- Forced alkaline diuresis: pH 7-8 Alkalinisation of the urine

Alkalinization is commonly usedcommonly usedcommonly usedcommonly used for:

Salicylate overdoseIsoniazid

Phenobarbitone

Methanol

Methotrexate

Forced diuresis (producing urine volumes up to 1L/h) is generally not usednot usednot usednot used because of the risk of fluid

overload.

Alkalinization with sodium bicarbonate:

1-2 mEq/kg in 15 ml/kg of 5% dextrose every one to two hours aiming to maintain pH of urine at

7.45and 7.55.

B- Forced acidic diuresis: pH < 5 Acidification of Urine

Urinary acidification using ammonium chloride has previously been used to enhance excretion of

weakly alkaline drugs (amphetamine, strychnine, quinine and phencyclidine) but danger of

acidosis & hyperammonaemia outweigh the benefits of this technique.

Obsolete nowadays

iviviviv. Haemodialysis:. Haemodialysis:. Haemodialysis:. Haemodialysis:i- Principle:Diffusion of particles across a semipermeable membrane from the higher concentration To a lower

concentration.


17/21

Basic Principles

ii- Technique:

Patient blood circulates through a semipermeable membrane tubing system which is

surrounded by a dialysate solution.

Haemodialysis with a flow rate of up to 300-500 ml/min can be achieved and clearance rate

may reach 200-300 ml/min.

iii- Precautions:

For dialysis to be effective toxin must be:

Small size (molecular weight < 500 daltons)

Highly water soluble.

Low protein binding

Small volume of distribution (< 2 L/kg)

AAAAs salicylate, methadone, vancomycin and Lithium).s salicylate, methadone, vancomycin and Lithium).s salicylate, methadone, vancomycin and Lithium).s salicylate, methadone, vancomycin and Lithium).

iv- Indications of heamodialysis (UnstableUnstableUnstableUnstable):

UUUUraemia

NNNNo response to conventional therapy

SSSSalicylates

TTTTheophylline

AAAAlcohols (isopropanol, methanol)

BBBBoric acid, barbiturates

LLLLithium

EEEEthylene glycol

N.B. Smaller, portable dialysis units that utilize a resin or filter to recycle a smaller volume dialysate do not

efficiently remove drugs and poisons and should not be used

vvvv. Haemoperfusion. Haemoperfusion. Haemoperfusion. Haemoperfusion::::i- Principle:

Using equipment and vascular access similar to that for haemodialysis.

ii- Technique:

Pateint blood is pumped directly through a column containing an adsorbent material (either

charcoal or amberlite resin).

iii- Indications of haemoperfusion:

Examples: carbamazepine, barbiturates and theophylline.iv- Advantages:

Because the drug or toxin is in direct contact with the adsorbent material, drugs size, watersolubility and protein binding are not important limiting factors.

For most drugs, haemoperfusion can achieve greater clearance rates than haemodialysis.

For example, the haemodialysis clearance for Phenobarbital is 60-80 ml/min, whereas the

heamoperfusion clearance is 200-300 ml/min

v- Disadvantages:

Systemic anticoagulation is required, often in higher doses than for haemodialysis andthrombocytopenia is a common complication

ViViViVi.... HaemofiltrationHaemofiltrationHaemofiltrationHaemofiltration::::i- Principle:

It can remove compounds with high molecular weight (>500 40000 daltons).

ii- Indications:

It is used in aminoglycoside, theophylline, iron and lithium overdoses.

N.B. Substances not amenable to significant extracorporeal removal include

Benzodiazepines, tricyclic compounds, phenqthiazines, chlordiazepoxide and dextropropoxyphene.

5555.... PeritonPeritonPeritonPeritoneal dialysis:eal dialysis:eal dialysis:eal dialysis:i- Advantages:

It is easier to perform than haemodialysis or haemoperfusion and does not require anticoagulant.

ii- Disadvantages:

It is only about 10-15 % as effective owing to poor extraction ratios and slower flow rates (clearancerates: 10-15 ml/min).

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 haemodialysis.

6666.... RepeatedRepeatedRepeatedRepeated----dose activadose activadose activadose activated charcoal:ted charcoal:ted charcoal:ted charcoal:i- Principle:

Repeated doses of activated charcoal:

(0.5 -1 gm/kg every 2-3 hours) are given orally or via gastric tube.

ii- Technique:

Constant slurry of activated charcoal in the intestinal lumen extracts drug or toxin from the gut wall in

a kind of gut dialysis

c) Quite distinct from simple adsorption of ingested unabsorbed tablets.

iii- Advantages:

It is easy, non-invasive and shortens the half-life of many toxins.

iv- Indications:

Phenobarbital, theophylline, carbamazepine, dapson, digitoxin, phenytoin, phenylbutazoneand salicylates.


18/21

Basic Principles

VVVV---- Symptomatic Treatment:Symptomatic Treatment:Symptomatic Treatment:Symptomatic Treatment: Rest In Bed:Rest In Bed:Rest In Bed:Rest In Bed:

At least 2 weeks is necessary as exhaustion may Heart Failure.

DDDDiets Deficiency:

Care of nutrition especially in cases of coma or corrosives where the swallowing is not possible.

DDDDehydration:

Fluids by all routes.

IV Glaucose , Saline and Ringer. RRRRespiratory Tract Irritation:

AAAAsphyxia: Due to acute oedema of epiglottis Tracheostomy.

PPPPulmonary Oedema: Due to direct irritation of the poison

Semisitting position

Atropine: 1mg IV To Bronchial Secretion.

Aminophyline: 500mg slowly IV : To Bronchial Spasm.

Antibiotic: Prophylactic Measure :To avoid Bronchopneuomonia.

Corticosteroids: In cases of hydrocarbons: To avoid Inflammation

RRRRespiratory embarrassment:

Oxygen inhalation.

Ventilation.

GGGGastro-Intestinal Tract Irritation:Demulcent Milk - Olive Oil

PPPPain:

Analgesic. UUUUrine Retention:

Catheterization.

IIIInfection:

Antibiotic as prophylactic measure.

MMMMetabolic Acidosis:

Na Bicarbonate Na HCO3 1.26% 1-2 mq/kg/hr

Repeated until: Blood pH return normal or Urine pH become alkaline.

RRRRenal Impairment:Compact The Renal Failure:

Adjust water and electrolyte intake & Maintain good urine output

Peritoneal Dialysis

Haemodiaysis

HHHHepatic Impairment:

Hepatic Extracts and Vitamins.

HHHHypotension:Saline 0.9% 10-20ml/kgIV.

If no response

Dopamine in 7-9 ug/kg/hour

If no response

Norepinephrine 0.1-0.2ug/kg/min At as vasopressor agent.

HHHHypertension:Benzodiazepine

To sympathetic over activity & stress If no response

Phentolamine

Acts as Blockers & stress If no response

Na Nitroprusside

Acts as a peripheral vasodilator

HHHHypoglycaemia: Glaucose 10% I.V. infusion

HHHHyperglycemia: Insulin therapy

HHHHypothermia: Blankets and Warm I.V. Fluid.

HHHHyperthermia: Cold Fomentation & Ice Bags

TTTTachycardia: B-Blockers.

BBBBradycardia: Atropine

UUUUnder observation & Follow up: Patient must be put under observation especially in homicidal or suicidal cases.

PPPPsychiatric consultation: in suicidal cases.


19/21

Basic Principles

6666---- ADMISSIONADMISSIONADMISSIONADMISSION PPPPOLICY IN CASES OF TOXICITY:OLICY IN CASES OF TOXICITY:OLICY IN CASES OF TOXICITY:OLICY IN CASES OF TOXICITY:

Decision about the need for hospitalization of poisoned patient presenting with possible accidental poisoning is sometimes

difficult.

Most patients will be asymptomatic and a short, period of observation, in an emergency department of admission ward, is

often required.

IIII---- General Indicating criteria for admissionGeneral Indicating criteria for admissionGeneral Indicating criteria for admissionGeneral Indicating criteria for admission::::

Anyone taking an overdose, however apparently trivial in amount.

Any one with self-harm.

IIIIIIII---- Special Indicating criteria for admission:Special Indicating criteria for admission:Special Indicating criteria for admission:Special Indicating criteria for admission:

Patient withPatient withPatient withPatient with delayed compliccompliccompliccomplicationsationsationsations from slow absorption of medications:e.g. from tablet concretion, sustained release or enteric coated preparations.

If specific drug levels are determined, obtain repeated serum levels to be certain that they are decreasing as

expected.

PatientPatientPatientPatient withwithwithwith delayed toxic time bombstoxic time bombstoxic time bombstoxic time bombs:e.g. acetaminophen, carbon tetrachloride, ethylene glycol, mercury, methanol and toxic mushrooms.

IIIIIIIIIIII---- Special Indicating criteria for ICU admission:Special Indicating criteria for ICU admission:Special Indicating criteria for ICU admission:Special Indicating criteria for ICU admission:

The decision to admit the patient to an intensive care setting should be individualized based on the initial presentation.

Patients who would require an ICU or monitored bedICU or monitored bedICU or monitored bedICU or monitored bed must have at least oneoneoneone of the following criteria: Intubation in the emergency room.

Hypercarpia.

QRS complex greater than or equal to 0.12 second.

Cardiac dysrhythmias other than sinus tachycardia.

Hypotension (systolic BPof less than 80).

Unresponsiveness to verbal stimuli.

Seizures.

Patients with tricyclic antidepressant overdose as they may develop sudden cardiac dysrhythmias and probably

warrant cardiac monitoring.

---- DSCHARGE POLICY IN CASES OF TOXICITY:DSCHARGE POLICY IN CASES OF TOXICITY:DSCHARGE POLICY IN CASES OF TOXICITY:DSCHARGE POLICY IN CASES OF TOXICITY:

When patients are fit to be discharged?When patients are fit to be discharged?When patients are fit to be discharged?When patients are fit to be discharged?

Patients are fit for discharge from inpatient care when:

They no longer require the specialist skillsThey no longer require the continous monitoring available in the ward.

This generally means they are:

Alert

Awake

Oriented

Have no life-threatening organ failure

Have been passed psychiatrically safe for discharge.

Patients mental state is the most important discharging criteria.

ALLALLALLALL PatientsPatientsPatientsPatients who have taken an overdose prior to discharge should be assessed by psychiatric doctor.

SOMESOMESOMESOME PPPPatients,atients,atients,atients, especially if family support is good, may be fit enough to return home after an overdose.

OthersOthersOthersOthers Patient ,Patient ,Patient ,Patient , with less family relationship may require psychiatric observation and nursing care.


20/21

Basic Principles

7777---- Psychiatric assessment IN CASES OF TOXICITYPsychiatric assessment IN CASES OF TOXICITYPsychiatric assessment IN CASES OF TOXICITYPsychiatric assessment IN CASES OF TOXICITY

Be sympathetic despite the hour Interview relatives and friends if possible.

Factors determineFactors determineFactors determineFactors determine the presentthe presentthe presentthe present suicidal toxicsuicidal toxicsuicidal toxicsuicidal toxic condition statecondition statecondition statecondition state::::

PPPPlanned act or not

PPPPrecautions against being found.PPPPatient seek help after suicidal act or not

PPPProblems led to the act: do they still exist?

PPPPresence of psychiatric disorder (depression, alcoholism, personality disorder, schizophrenia, and dementia)

PPPPatient resources (friends, family, work, personality)?

FFFFactors increase the chance of future suicide:actors increase the chance of future suicide:actors increase the chance of future suicide:actors increase the chance of future suicide:

PPPPresent intention is to die.

PPPPresence of psychiatric disorder.

PPPPoor resources.

PPPPrevious suicide attempts.PPPPatient, Male, Socially isolated, Unemployed and Over 50 yrs old.

Factors prevent the acuteFactors prevent the acuteFactors prevent the acuteFactors prevent the acute toxicity in psychiatric patienttoxicity in psychiatric patienttoxicity in psychiatric patienttoxicity in psychiatric patient::::

PPPPatient:Adult education

HHHHealthprofessionals:Vigilance by health professionals to recognize the early signs of abuse and potential suicide.

MMMMedicine:Double-check dosage before administration.

Put all medicines and household chemicals in a locked child-proof cupboard >1.5 m off the ground.

Safely dispose of medicines, chemicals which are not needed or out of date.Keep all medicines and chemicals in their or iginal containers with clear label.


21/21

Basic Principles

8888---- MedicoMedicoMedicoMedico----legal issues IN Cases of toxicity:legal issues IN Cases of toxicity:legal issues IN Cases of toxicity:legal issues IN Cases of toxicity:

A mentally competent adult has every right to withhold consent to examination, investigation or medical treatment, even ifsuch a decision may result in his or her death.

It is therefore important to asses the capacity for competence.

It is often best that a third person, such as a nurse, witness such assessment and it is vital that adequate documentation ismade.

---- AssessAssessAssessAssessing capacity foring capacity foring capacity foring capacity for competence:competence:competence:competence:

To show that patients are competent to refuse medical treatment.

- Patients must be able to:

UUUUnderstand and retain,nderstand and retain,nderstand and retain,nderstand and retain, informationinformationinformationinformation on the treatment proposed

Its indications, its main benefits, as well as possible risks and the consequences of non-treatment.

BBBBelieve telieve telieve telieve that informationhat informationhat informationhat information.

WWWWeighing up the informationeighing up the informationeighing up the informationeighing up the information in order arrive at a conclusion.

---- Valid Consent:Valid Consent:Valid Consent:Valid Consent:

- If a patient is capable of all three of these elementsthree of these elementsthree of these elementsthree of these elements, refusal of treatment must be judged as valid and respectedjudged as valid and respectedjudged as valid and respectedjudged as valid and respected.

---- Family and Friend Support:Family and Friend Support:Family and Friend Support:Family and Friend Support:

- It is essential to maintain a supportive approach and the support of family and friends can be invaluable at the

stage.

---- Second OpinionSecond OpinionSecond OpinionSecond Opinion SupportSupportSupportSupport::::

- If there is any doubt on the assessment of capacity, get a second opinion, ideally from a psychiatrist.

- A particularly difficult situation arises if a patient who has capacity but later on becomes unconscious - in such

cases treatment cannot be given in the absence of prior consent.

---- Treatment can be only given to a patient against her/his will in the following cirTreatment can be only given to a patient against her/his will in the following cirTreatment can be only given to a patient against her/his will in the following cirTreatment can be only given to a patient against her/his will in the following circumstances:cumstances:cumstances:cumstances:

---- Mental Illness:Mental Illness:Mental Illness:Mental Illness:

If the patient is detainable under the Mental Health Act 1983.

However, the MENTAL Health Act allows for treatment for mental disorders to be given without the patient's consent,

but dose not allow for medical treatment to be given without THE patient's consent.

Under common law if a patient lacks. Mental to capacity, a doctor may administer any medical treatment essential

to preserve life and considered to be in the patient's best interests.

This also applies to the patient who is brought to the hospital unconscious requiring emergency treatment.

---- ChildrenChildrenChildrenChildren::::

In patients under the age of 16 years, assessment of the individual child's understanding will determine whether he or

she can give consent to medical treatment.

Children over 16 are treated as adults.

Date post:	04-Apr-2018
Category:	Documents
Upload:	muhammad-maroof-ahmad
View:	224 times
Download:	1 times

-Basic Clinical Toxicology

Documents