Emergency Medicine Australasia (2004) 16 456ndash458

Blackwell Publishing LtdToxicologyPosition statement OP poisoning in the ED

Consensus statement Risk of nosocomial organophosphate poisoning in emergency departmentsMark Little and Lindsay MurrayUniversity of Western Australia Sir Charles Gairdner Hospital Perth Western Australia and The New South Wales Western Australian and Queensland Poisons Information Centres Australia

There is great concern regarding the risk of nosocomialpoisoning in staff caring for the organophosphate(OP) pesticide poisoned patient in prehospital EDand intensive care settings In many instances elaboratenursing practices including the use of personal pro-tective equipment (PPE) have been developed in orderto reduce this risk Elsewhere HAZMAT responseshave been instituted in response to OP poisoningand resulted in closures of highways and EDs withthe result that the victim has been denied access tostandard hospital and transport facilities Suchactions compromise not only the care of the poison-ing victim but that of others reliant on those healthcare facilities and systems We will briefly reviewthe evidence in the literature regarding nosocomialOP poisoning examine some of the reasons why sym-ptoms occur amongst staff treating OP-poisoned pati-ents and provide consensus guidelines on reasonableprecautions that should be taken when managingthese patients

The clinical features of OP pesticide poisoning ariseas a result of cholinesterase inhibition Significantpoisoning almost always occurs in the context ofingestion and can be confirmed by assays of either redcell or plasma cholinesterase activity The poisoning

associated with inhalational or dermal exposure toOPs is generally mild or nonexistent

Most available OP preparations contain the activeorganophosphate chemical dissolved in a hydrocarbonsolvent OP compounds themselves have extremelylow volatility Vapour pressures for OP compounds areusually in the order of mPa at room temperature (egfenthion 074 mPa at 20degC chlorpyrifos 3 mPa at25degC)1 Indeed they would be ineffective as pesticides ifthey were to vaporize rapidly following application toplants or soil In contrast the hydrocarbon solventsare highly volatile with vapour pressures quoted inkPa (eg toluene 293 kPa at 20degC xylene 091 kPa at20degC)2

On a global basis OP poisoning is common andhas a high case fatality rate In China alone there arean estimated 170 000 deaths annually from pesticidepoisoning mainly from OPs and virtually all as aresult of deliberate self-poisoning by ingestion3 Theincidence of self-poisoning with OP pesticides is muchlower in developed nations however the potential forlethality without treatment remains high

There have been a number of reports of nosocomialpoisoning occurring in staff caring for patients whohave self-poisoned with OPs4ndash7 These reports are

Correspondence Dr Mark Little Sir Charles Gairdner Hospital Hospital Avenue Nedlands WA 6009 Australia E-mail marklittlehealthwagovau

Lindsay Murray MBBS FACEM Senior Lecturer Consultant Emergency Physician and Clinical Toxicologist Mark Little MBBS FACEM MPHTM DTMampH (Lon) Clinical Senior Lecturer Consultant Emergency Physician and Clinical Toxicologist

A consensus statement prepared by the medical consultants to the Poison Information Centres of New South Wales Western Australiadagger QueenslandDagger New Zealandsect and the Australian Capital Territorypara Mark LittledaggerDagger Lindsay MurraydaggerDagger Frank DalydaggerDagger Andis Graudins Dagger Geoff IsbisterDagger Ian WhyteDagger Rob DowsettDagger Betty ChanDagger JohnFountainsect and Nick Buckleypara

Position statement OP poisoning in the ED

457

frequently cited to support the need for institution ofextreme protocols to protect staff from secondarypoisoning In each of these reports the clinical featuresdescribed (including eye irritation nausea lacrima-tion headache cough) could be attributed to exposureto solvent fumes and in not a single case is thediagnosis of OP poisoning supported by documenteddepression in cholinesterase activity There are tworeports of staff actually requiring treatment follow-ing nosocomial exposure to OPs Documentation ofexposure in both cases was extremely poor Two peoplebecame unwell after performing mouth-to-mouth ina prehospital setting on a 19-year-old female whohad ingested an OP4 Cholinesterase activity wasnot assayed but they were treated with atropineand pralidoxime The only serious case of nosocomialpoisoning is reported by Geller et al from GeorgiaUSA5 Three staff involved in the care of a patient whohad ingested a veterinarian insecticide (73 naph-thalene xylene surfactant and 116 phosmet) werepoisoned One staff member required ventilation andwas administered atropine and pralidoxime Anotherreceived atropine and pralidoxime for 12 h The patientwas not decontaminated The staff did not wear anyskin protective clothing Cholinesterase activity wasnot assayed In the only report where cholinesteraseactivity was actually measured the results were allwell within normal range even for the 14 symptomatichealth care workers6 This suggests that the reportedsymptoms were not due to significant OP poisoningNone of the 25 staff who managed a patient with OPingestion in a United Kingdom ED developed anysymptoms suggestive of OP poisoning7 NosocomialOP poisoning has not been reported from thosedeveloping nations with a high incidence of self-poisoning with OPs Health workers in those countriesdo not use PPE and do not perceive themselves to be arisk The combined experience of all the authorsincludes the treatment of over 100 patients with OPpoisoning and no similar cases have been observedand nor are we aware of any other cases manifestingeither clear evidence of cholinergic toxicity or requir-ing intubation

In summary there is little evidence to support theassumption that staff caring for OP-poisoned patientsare at any risk of developing secondary nosocomial OPpoisoning under normal circumstances Theoreticalconsiderations and the absence of reports from thosecountries where OP poisoning is a common clinicalproblem would suggest strongly that it does notoccur

It is important that staff caring for OP-poisoningvictims recognize that the distinctive odours that maybe experienced relate to the hydrocarbon solvent andnot the OP compound Exposure to hydrocarbonvapours can cause mild self-limiting symptoms andthe occurrence of these symptoms can be limited bycaring for the patient in a well-ventilated area togetherwith regular rotation (every 30 min) of staff

Staff should adopt universal precautions to avoiddermal exposure to OP compounds All OP-poisonedpatients should have their clothes removed andbagged on arrival and their bodies washed with soapand water The patient who has ingested an OP-containing pesticide may also have some of theproduct on their skin or clothes Their body secretionsmay contain small concentrations of OP and directcontact should be avoided Personal protective equip-ment does not need to be routinely worn for themanagement of OP-poisoned patients Measures toavoid secondary exposure to OP-containing pesticidesshould never be instituted to the detriment of timelyand effective transport assessment and treatment ofthe poisoned patient

Summary of recommended precautions when managing poisoning with organophosphate-containing pesticides

bull Resuscitation and further treatment should ideallytake place in a well-ventilated area with regularrotation of staff

bull All staff with direct patient contact shouldobserve universal precautions mdash gloves gowns eyeprotection

bull Patients should undergo external decontaminationas soon as practicable clothes removed and baggedand body washed with soap and water Thisprocess should not take place to the detriment oftimely resuscitation and medical assessment

bull Staff inadvertently coming into direct contact withpatientrsquos bodily secretions should immediately andthoroughly wash the affected area

Accepted 23 July 2004

References

1 The Pesticide Manual 13th edn United Kingdom British CropProtection Council Alton 2003

M Little and L Murray

458

2 IPCS Intox Databank Available from URL httpwwwintoxorgdatabankindexhtm [Accessed 13th July 2004]

3 Eddleston M Phillips MR Self poisoning with pesticides BMJ2004 328 42ndash4

4 Koksal N Akif Buyukbese M Guven A Cetinkaya AHasanoglu HC Organophosphate intoxication as a consequenceof mouth-to-mouth breathing from an affected case Chest 2002122 740ndash1

5 Geller RJ Singleton KL Tarantino ML Nosocomial poisoning

associated with emergency department treatment oforganophosphate toxicity mdash Georgia 2000 Morb Mortal WklyRep 2001 49 1156ndash8

6 Butera R Locatelli C Barretta S et al Secondary exposure tomalathion in emergency department health-care workers[Abstract] J Toxicol Clin Toxicol 2002 40 386ndash7

7 Stacey R Morfey D Payne S Secondary contamination inorganophosphate poisoning analysis of an incident QJM 200497 75ndash80

Position statement OP poisoning in the ED

457

frequently cited to support the need for institution ofextreme protocols to protect staff from secondarypoisoning In each of these reports the clinical featuresdescribed (including eye irritation nausea lacrima-tion headache cough) could be attributed to exposureto solvent fumes and in not a single case is thediagnosis of OP poisoning supported by documenteddepression in cholinesterase activity There are tworeports of staff actually requiring treatment follow-ing nosocomial exposure to OPs Documentation ofexposure in both cases was extremely poor Two peoplebecame unwell after performing mouth-to-mouth ina prehospital setting on a 19-year-old female whohad ingested an OP4 Cholinesterase activity wasnot assayed but they were treated with atropineand pralidoxime The only serious case of nosocomialpoisoning is reported by Geller et al from GeorgiaUSA5 Three staff involved in the care of a patient whohad ingested a veterinarian insecticide (73 naph-thalene xylene surfactant and 116 phosmet) werepoisoned One staff member required ventilation andwas administered atropine and pralidoxime Anotherreceived atropine and pralidoxime for 12 h The patientwas not decontaminated The staff did not wear anyskin protective clothing Cholinesterase activity wasnot assayed In the only report where cholinesteraseactivity was actually measured the results were allwell within normal range even for the 14 symptomatichealth care workers6 This suggests that the reportedsymptoms were not due to significant OP poisoningNone of the 25 staff who managed a patient with OPingestion in a United Kingdom ED developed anysymptoms suggestive of OP poisoning7 NosocomialOP poisoning has not been reported from thosedeveloping nations with a high incidence of self-poisoning with OPs Health workers in those countriesdo not use PPE and do not perceive themselves to be arisk The combined experience of all the authorsincludes the treatment of over 100 patients with OPpoisoning and no similar cases have been observedand nor are we aware of any other cases manifestingeither clear evidence of cholinergic toxicity or requir-ing intubation

In summary there is little evidence to support theassumption that staff caring for OP-poisoned patientsare at any risk of developing secondary nosocomial OPpoisoning under normal circumstances Theoreticalconsiderations and the absence of reports from thosecountries where OP poisoning is a common clinicalproblem would suggest strongly that it does notoccur

It is important that staff caring for OP-poisoningvictims recognize that the distinctive odours that maybe experienced relate to the hydrocarbon solvent andnot the OP compound Exposure to hydrocarbonvapours can cause mild self-limiting symptoms andthe occurrence of these symptoms can be limited bycaring for the patient in a well-ventilated area togetherwith regular rotation (every 30 min) of staff

Staff should adopt universal precautions to avoiddermal exposure to OP compounds All OP-poisonedpatients should have their clothes removed andbagged on arrival and their bodies washed with soapand water The patient who has ingested an OP-containing pesticide may also have some of theproduct on their skin or clothes Their body secretionsmay contain small concentrations of OP and directcontact should be avoided Personal protective equip-ment does not need to be routinely worn for themanagement of OP-poisoned patients Measures toavoid secondary exposure to OP-containing pesticidesshould never be instituted to the detriment of timelyand effective transport assessment and treatment ofthe poisoned patient

Summary of recommended precautions when managing poisoning with organophosphate-containing pesticides

bull Resuscitation and further treatment should ideallytake place in a well-ventilated area with regularrotation of staff

bull All staff with direct patient contact shouldobserve universal precautions mdash gloves gowns eyeprotection

bull Patients should undergo external decontaminationas soon as practicable clothes removed and baggedand body washed with soap and water Thisprocess should not take place to the detriment oftimely resuscitation and medical assessment

bull Staff inadvertently coming into direct contact withpatientrsquos bodily secretions should immediately andthoroughly wash the affected area

Accepted 23 July 2004

References

1 The Pesticide Manual 13th edn United Kingdom British CropProtection Council Alton 2003

M Little and L Murray

458

2 IPCS Intox Databank Available from URL httpwwwintoxorgdatabankindexhtm [Accessed 13th July 2004]

3 Eddleston M Phillips MR Self poisoning with pesticides BMJ2004 328 42ndash4

4 Koksal N Akif Buyukbese M Guven A Cetinkaya AHasanoglu HC Organophosphate intoxication as a consequenceof mouth-to-mouth breathing from an affected case Chest 2002122 740ndash1

5 Geller RJ Singleton KL Tarantino ML Nosocomial poisoning

associated with emergency department treatment oforganophosphate toxicity mdash Georgia 2000 Morb Mortal WklyRep 2001 49 1156ndash8

6 Butera R Locatelli C Barretta S et al Secondary exposure tomalathion in emergency department health-care workers[Abstract] J Toxicol Clin Toxicol 2002 40 386ndash7

7 Stacey R Morfey D Payne S Secondary contamination inorganophosphate poisoning analysis of an incident QJM 200497 75ndash80

M Little and L Murray

458

2 IPCS Intox Databank Available from URL httpwwwintoxorgdatabankindexhtm [Accessed 13th July 2004]

3 Eddleston M Phillips MR Self poisoning with pesticides BMJ2004 328 42ndash4

4 Koksal N Akif Buyukbese M Guven A Cetinkaya AHasanoglu HC Organophosphate intoxication as a consequenceof mouth-to-mouth breathing from an affected case Chest 2002122 740ndash1

5 Geller RJ Singleton KL Tarantino ML Nosocomial poisoning

associated with emergency department treatment oforganophosphate toxicity mdash Georgia 2000 Morb Mortal WklyRep 2001 49 1156ndash8

6 Butera R Locatelli C Barretta S et al Secondary exposure tomalathion in emergency department health-care workers[Abstract] J Toxicol Clin Toxicol 2002 40 386ndash7

7 Stacey R Morfey D Payne S Secondary contamination inorganophosphate poisoning analysis of an incident QJM 200497 75ndash80