OrganophosphateMANAGEMENT

TOXICOLOGIC PRESENTATIONS · 12 SECTIONS

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464 items

☷ Legend

01Approach to the Critical Patient/attcp55

Immediate priorities

›Resuscitation workflow

›Airway threat

›Copious secretions

›Bronchospasm

›Hypoventilation

›Breathing failure

›SpO2 target 94% to 98%

›ETCO2 trend for ventilation adequacy

›Circulatory instability

›Hypotension

›Bradycardia

›Neurologic instability

›Seizure activity

›Coma

›Immediate antidote readiness

›Atropine bedside

›Oxime bedside

›Benzodiazepine bedside

Decontamination and safety

›Scene and staff safety

›PPE escalation

›Gloves

›Gown

›Eye protection

›Respiratory protection for ongoing off gassing concern

›Secondary contamination prevention

›Contaminated clothing removal

›Bag and seal belongings

›Skin decontamination

›Soap and water wash

›Repeat wash if oily residue persists

›Ocular decontamination

›Irrigation until symptom resolution

›pH normalization if available

›GI decontamination

›Activated charcoal within 1 hour for protected airway and significant ingestion

›Avoid charcoal in uncontrolled emesis or unprotected airway

Key clinical decision points

›Toxidrome recognition

›Cholinergic syndrome pattern

›Bronchorrhea

›Bronchospasm

›Bradycardia

›Miosis

›Diaphoresis

›Fasciculations

›Organophosphate vs carbamate implications

›Oxime benefit strongest with organophosphate

›Carbamate inhibition often reversible and shorter duration

›Early airway control triggers

›Persistent hypoxia despite suction and atropine

›Refractory bronchospasm

›Recurrent seizures

›Worsening hypercapnia

›Consult triggers

›Poison center early involvement

›ICU activation for any respiratory failure or atropine infusion need

02History/hx58

Exposure characterization

›Exposure profile

›Agent category

›Insecticide

›Nerve agent concern

›Formulation

›Liquid concentrate

›Powder

›Fogger or spray

›Route

›Inhalation

›Dermal

›Ingestion

›Ocular

›Timing

›Time of exposure

›Time of symptom onset

›Dose proxy

›Amount handled or ingested

›Duration of exposure

›Enclosed space exposure

Symptom inventory

›Symptom pattern

›Muscarinic features

›Salivation

›Lacrimation

›Urination

›Diarrhea

›Bronchorrhea

›Bronchospasm

›Bradycardia

›Vomiting

›Nicotinic features

›Fasciculations

›Weakness

›Paralysis

›Hypertension early

›Tachycardia early

›CNS features

›Agitation

›Seizures

›Confusion

›Coma

Risk modifiers

›Host and context risks

›Occupational use

›Agriculture

›Pest control

›Co exposures

›Hydrocarbons in formulations

›Solvents

›Medication context

›Beta blocker use

›Calcium channel blocker use

›Comorbidities

›Asthma or COPD

›Cardiovascular disease

›Intent documentation

›Accidental

›Occupational

›Intentional self poisoning

03Physical Exam/exam36

Primary survey focused findings

›High yield exam targets

›Airway secretion burden

›Oral pooling

›Frothy sputum

›Respiratory mechanics

›Wheeze

›Crackles

›Accessory muscle use

›Perfusion

›Bradycardia

›Hypotension

›Cool extremities late

›Neuromuscular status

›Fasciculations

›Proximal weakness

›Respiratory muscle fatigue

›Pupils

›Miosis

›Variable size with hypoxia or co ingestion

Cholinergic toxidrome confirmation

›Pattern consistency

›Skin findings

›Diaphoresis

›Increased secretions

›GI findings

›Hyperactive bowel sounds

›Diarrhea

›GU findings

›Urinary incontinence

›CNS findings

›Altered mental status

›Seizures

PITFALLS

›Diagnostic pitfalls

›Miosis absence in severe hypoxia

›Tachycardia early due to nicotinic effect or stress

›Wheeze misattributed to asthma without secretion assessment

›Underestimation of dermal exposure from soaked clothing

04Differential Diagnosis/ddx39

Life threats with similar presentation

›Alternate critical causes

›Nerve agent exposure

›Rapid onset in multiple victims

›Mass casualty context

›Opioid toxidrome

›Miosis

›Hypoventilation

›Nicotine poisoning

›Fasciculations

›Bradycardia late

›Beta blocker toxicity

›Bradycardia

›Hypotension

›Calcium channel blocker toxicity

›Bradycardia

›Hyperglycemia

›Organophosphate induced bronchospasm mimics asthma

›Bronchorrhea prominence

›Secretions as primary driver

Mimics and confounders

›Non toxicologic mimics

›Sepsis

›Hypotension

›Altered mental status

›Noncardiogenic pulmonary edema

›Hypoxia

›Crackles

›Cholinergic medications

›Pilocarpine

›Bethanechol

›Mushroom poisoning

›Muscarine containing species

›Coding anchors

›ICD-10 T60.0X1

›Accidental poisoning by organophosphate and carbamate insecticides

›ICD-10 T60.0X2

›Intentional self poisoning by organophosphate and carbamate insecticides

›SNOMED CT concept

›Organophosphate poisoning

›Cholinergic crisis

05Laboratory Tests/lt39

Core tests for severity and complications

›Baseline labs

›Blood gas

›pH

›PaCO2 mmHg

›PaO2 mmHg

›Electrolytes

›Sodium mmol/L

›Potassium mmol/L

›Bicarbonate mmol/L

›Renal function

›Creatinine umol/L

›Glucose mmol/L

›Hypoglycemia exclusion

›Stress hyperglycemia context

›Lactate mmol/L

›Tissue hypoperfusion marker

›Creatine kinase

›Rhabdomyolysis from seizures or fasciculations

›Complete blood count

›Aspiration pneumonia support

›Cardiotoxicity screening

›Troponin for concerning symptoms

›Chest pain

›Shock

Cholinesterase testing

›Enzyme activity tests

›RBC acetylcholinesterase

›Better correlation with neuromuscular impairment

›Slow turnaround common

›Plasma butyrylcholinesterase

›More available in many centers

›Less specific for clinical severity

›Interpretation guidance

›Baseline unknown in most patients

›Clinical response over lab normalization for acute titration

›Persistently low levels support diagnosis and ongoing exposure

PITFALLS

›Lab limitations

›Cholinesterase levels may be normal early

›Carbamate exposure may show transient suppression

›Coformulants may drive lung injury independent of cholinesterase

06Diagnostic Tests/dt40

Scoring Systems

›Severity stratification tools

›Peradeniya Organophosphorus Poisoning scale

›Pupil size category

›Respiratory rate category

›Heart rate category

›Fasciculations category

›Level of consciousness category

›Seizures category

›Clinical use

›Higher score association with ventilation need

›Bedside trending for trajectory

›Limitations

›Not validated for all agents

›Treatment effects alter components

MRI

›Neuroimaging considerations

›Indications

›Persistent focal neurologic deficit

›Prolonged coma after stabilization

›Expected yield

›Low for routine organophosphate management

›Safety

›Airway and infusion support compatibility

›Targeted CT use

›CT head indications

›Refractory seizure concern for alternate cause

›Trauma concern from collapse

›CT chest indications

›Aspiration pneumonia concern

›Alternative pulmonary diagnosis concern

›Limitations

›Does not guide atropine titration

Ultrasound

›POCUS adjuncts

›Lung ultrasound

›B lines for pulmonary edema pattern

›Pleural effusion assessment

›Cardiac ultrasound

›LV function for shock differential

›Volume status support

›Airway ultrasound

›ETT confirmation if difficult auscultation environment

07Disposition/dispo22

Level of care criteria

›ICU indications

›Any ventilatory support requirement

›Persistent bronchorrhea needing ongoing atropine infusion

›Recurrent seizures

›Hemodynamic instability

›Significant weakness or paralysis

›Step down or monitored bed criteria

›Symptoms controlled without infusion

›No oxygen requirement after observation

›Stable vitals without recurrent secretions

Observation and discharge criteria

›Observation parameters

›Minimum observation after symptom resolution

›6 to 8 hours for minor exposure

›Longer for long acting organophosphates

›Re exposure risk assessment

›Contaminated home environment

›Occupational return planning

›Discharge suitability

›Asymptomatic off atropine for sustained period

›Normal respiratory exam

›Reliable follow up

›Safe environment free of ongoing exposure

08Treatment/t90

Supportive care

›Airway and ventilation

›Oxygen and suction

›Aggressive suctioning for secretion control

›Yankauer and deep suction readiness

›Intubation considerations

›Early intubation for secretion burden and fatigue

›Avoid succinylcholine due to prolonged paralysis risk with cholinesterase inhibition

›Rocuronium preferred neuromuscular blocker

›Bronchospasm therapies

›Inhaled beta agonist adjunct

›Atropine as primary secretion and bronchospasm driver control

›Fluids and hemodynamics

›Isotonic crystalloid bolus for hypotension

›Vasopressor support if refractory after atropinization

›Norepinephrine infusion for persistent shock

Antidotes

›Antimuscarinic therapy

›Atropine

›Adult IV bolus

›Initial 1 mg to 3 mg IV

›If no improvement in secretions, double dose every 3 to 5 minutes

›Endpoint

›Drying of bronchial secretions

›Improved oxygenation and ventilation

›Pediatric IV bolus

›0.02 mg/kg IV

›Minimum 0.1 mg

›Maximum single dose 2 mg

›Infusion after stabilization

›Start 10% to 20% of total effective loading dose per hour

›Titrate every 5 to 15 minutes to secretion control

›Wean when stable without recurrent bronchorrhea

›Adverse effects monitoring

›Hyperthermia

›Ileus

›Urinary retention

›Delirium

›Cholinesterase reactivation

›Pralidoxime

›Indications

›Suspected organophosphate exposure

›Fasciculations or weakness

›Respiratory failure

›Adult dosing

›2 g IV over 20 to 30 minutes

›Repeat 2 g in 1 hour if ongoing weakness or secretions

›Maintenance infusion 500 mg per hour to 1 g per hour

›Pediatric dosing

›25 mg/kg IV over 20 to 30 minutes

›Maximum 2 g

›Maintenance infusion 10 mg/kg per hour to 20 mg/kg per hour

›Timing considerations

›Earlier use before aging for many organophosphates

›Continued benefit for ongoing exposure or persistent paralysis

›Carbamate considerations

›Routine use controversial

›Consider if severe nicotinic features and high suspicion of organophosphate cannot be excluded

›Seizure control and neuroprotection

›Benzodiazepines

›Diazepam IV

›5 mg to 10 mg IV

›Repeat every 5 to 10 minutes to seizure control

›Lorazepam IV

›2 mg to 4 mg IV

›Repeat once to twice as needed

›Pediatric lorazepam IV

›0.1 mg/kg IV

›Maximum 4 mg

›Refractory seizure pathway

›Levetiracetam IV 60 mg/kg

›Maximum 4500 mg

Monitoring and endpoints

›Response targets

›Secretions controlled

›Dry lung fields on auscultation

›Reduced suction requirement

›Ventilation stabilized

›Improving PaCO2 mmHg

›Improving ETCO2 trend

›Neuromuscular recovery

›Reduced fasciculations

›Improving strength

›Complication prevention

›Aspiration precautions

›Head of bed elevation

›Early airway protection when needed

›Temperature management

›External cooling if hyperthermia

›Evidence framing

›Atropine titration to drying secretions supported by expert consensus

›Oxime therapy for organophosphate associated weakness supported by toxicology consensus and multiple observational datasets

›Benzodiazepines for seizure control consistent with Class I seizure management principles

09Special Populations/sp28

Pregnancy

›Pregnancy considerations

›Maternal stabilization priority

›Oxygenation optimization

›Aggressive secretion control

›Antidote use

›Atropine use when clinically indicated

›Pralidoxime use when organophosphate suspected

›Fetal considerations

›Continuous fetal monitoring for viable gestation when feasible

›Obstetrics consultation early for moderate to severe cases

Geriatric

›Older adult considerations

›Lower physiologic reserve

›Earlier respiratory failure

›Higher aspiration risk

›Atropine adverse effects sensitivity

›Delirium risk

›Urinary retention risk

›Disposition bias

›Lower threshold for admission and monitoring

Pediatrics

›Pediatric considerations

›Higher risk of dermal absorption

›Larger surface area to mass ratio

›Faster decompensation

›Dosing safety

›Weight based atropine and pralidoxime dosing

›Minimum atropine dose to avoid paradoxical bradycardia

›Safeguarding

›Child protection involvement for unsafe storage concerns

10Background/b29

Epidemiology

›Population patterns

›Common global pesticide poisoning exposure in agricultural settings

›Higher intentional self poisoning burden in some regions

›Seasonal clustering with farming cycles

Pathophysiology

›Mechanism of toxicity

›Acetylcholinesterase inhibition

›Acetylcholine accumulation at synapses

›Muscarinic overstimulation

›Nicotinic overstimulation

›CNS overstimulation

›Organophosphate aging

›Time dependent increased stability of enzyme inhibition

›Reduced oxime effectiveness after aging for some agents

›Carbamate reversibility

›Spontaneous hydrolysis common

›Often shorter duration

Therapeutic Considerations

›Antidote logic

›Atropine blocks muscarinic receptors

›Secretion control as primary endpoint

›Heart rate normalization as secondary effect

›Oximes restore enzyme activity when feasible

›Greatest benefit for nicotinic weakness and paralysis

›Early administration preferred for many organophosphates

›Seizure control reduces hypoxia and rhabdomyolysis risk

›Intermediate syndrome awareness

›Delayed weakness after initial stabilization

›Proximal muscle weakness

›Respiratory muscle weakness

›Need for prolonged monitoring in significant poisonings

11Patient Discharge Instructions/pdi18

copy discharge instructions

›Discharge counseling

›Exposure avoidance

›Do not return to contaminated area until cleaned and ventilated

›Wash skin and hair again at home if any residue concern

›Launder exposed clothing separately in hot wash

›Return to ED now

›Trouble breathing

›Wheezing

›Persistent cough with frothy sputum

›New or worsening weakness

›Confusion

›Seizure

›Vomiting that does not stop

›Slow heart rate or fainting

›Follow up

›Primary care within 24 to 72 hours if symptoms occurred

›Occupational medicine follow up for workplace exposures

›Poison center contact information provided if available locally

12References/r10

Clinical guidelines and evidence sources

›Core toxicology references

›Poison control center consultation standards for pesticide poisoning management

›WHO pesticide poisoning guidance documents for organophosphate management

›ATSDR medical management guidelines for organophosphate compounds

›Goldfrank’s Toxicologic Emergencies sections on organophosphates and carbamates

›Evidence and consensus framing

›Atropine titration to bronchorrhea control supported by toxicology consensus

›Pralidoxime use in organophosphate poisoning supported by mixed trial data and expert consensus

›Benzodiazepines first line for toxin associated seizures supported by emergency neurology standards

›Internal project source citation

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed June 16, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.