Toxidromes & Treatments

PEDIATRIC TOXICOLOGY Badrinath Narayan, PEM FellowPediatric AHD, Aug 5th 2014PEDIATRIC TOXICOLOGY ObjectivesProvide a general approach to the poisoned patientHistory, physical, investigationsIntroduce types of decontamination with indications/complicationsList Pills that KillPoisoningPoisoningOne of the most common medical emergenciesExploratory behaviourChild abuseEnvironmental exposuresSuicide attemptsIn utero toxicantsPediatricians have a role in advocacyModes of exposure:Ingestion, ocular exposure, topical exposure, envenomation, inhalation and transplacental exposure.

ApproachBrief window of opportunity to make critical diagnostic and management decisionsPrioritize critical assessment and simultaneous management interventions14 year old female found unconscious in a park by friendsThe patient is brought into the trauma bay at BCCH EDWhat would you do?Primary Survey - ABCDEFGApply monitors - O2, HR, RR, cycling BPObtain vitals: HR, RR, BP, O2 satA Maintain patency, assess reflexes, note GCS, have airway equipment readyB - Apply O2, consider ETCO2, ABGC Assess perfusion, Get two large bore IvsDisability (GCS, pupil size and reactivity), ? Signs of traumaDecontaminationDrug Treatment dextrose, oxygen, narcanBedside Glucose

Primary SurveyPay special attention to:Evidence of impaired airway protective reflexesMany poisoned patients will vomitElective endotracheal intubation may be indicated at a lower thresholdAnticipate imminent respiratory failureCyanosis/apnea are late findingsCaseThe patient has been stabilized

What would you ask?History known intoxicantTake standard AMPLE history plus:What was ingested, How much, When, Why?Obtain prescription bottles when possible, and be sure that bottles contain med listedTalk to patients family and friends in ED/contact homeEnsure belongings are looked at to identify paraphernaliaIn a toddler think single pills, in an adolescent think co-ingestions!!When to suspect?Suspected but unknown intoxicant:Acute onset of illnessPica-prone age (1-5)History of pica, ingestionsCurrent household stressSignificantly altered mental statusFamily medications/recent illnessesSocial: grandparents visiting, holiday parties, other eventsCaseOn exam what things might you see to suggest a toxicological cause for the childs presentation?PhysicalVitalsGCS/mental statusPupils, EOM, fundiMouth: corrosive lesions, odors, secretionsRespiratory: rate, chest excursion, air entryCVS: rate, rhythm, perfusionGI: motility, corrosive effectsSkin colour, burns, diaphorsis, piloerection, track marksBladder size

Odours

CAMPHOR has a distinct aromatic odor (Vicks)Oil of wintergreenCyanide bitter almonds13Removal of toxic substanceDecontamination:Removal of a substance prior to entry into the circulationElimination:Removal of a substance by enhanced excretion once it has entered the circulationApproach to decontaminationGet help -- Poison control centre24-hour Line: 604-682-5050 or 1-800-567-8911Healthcare professionals only line:604-707-2787 or 1-866-298-5909 (outside the Lower Mainland)Monday to Friday from 9 am - 4 pmForms of DecontaminationTopicalflush aggressively (ocular or skin), remove contaminated clothingDilutionIpecac (no longer recommended; AAP statement against it)Activated CharcoalGastric Lavage also fallen out of favourWhole Bowel IrrigationDilutionIndicated if toxin produces only simple irritationControversial for caustic agents May be used in first few minutesNOT for drugs may increase absorptionNot if upper airway compromiseWater or milkE.g. dish soapActivated CharcoalActivation increases surface area of particlesToxins adsorb to activated charcoal decreasing amount adsorbed by the body Some toxins are not well adsorbed most small moleculesIron, the alcohols, lithium, strong acids and alkali, sodium, chloride.Dose: 10:1 charcoal to drug ratio. For unknown ingestions dosing is based on ability to tolerate the agent: Children - 1 gram/kg of body weight.TSA of charcoal preparation is related to amount of drug able to be adsorbed. 18Activated CharcoalTimingIf not contraindicated there does not seem to be a reasonable time that is too late to give AC, especially with SR or DR productsDogma used to be an hour but studies with respect to delayed gastric emptying have challenged this data Multiple-dose activated charcoalsustained-release productsuseful with drugs with low Vd, low protein binding, long half-lifeActivated CharcoalActivated charcoal not useful with:P esticidesH ydrocarbonsA cids, Alkali, AlcoholsI ronL ithium, LiquidsS olventsActivated CharcoalContraindicationsabsent gut motility or perforationif endoscopic visualization is required (e.g. caustic ingestions)loss of protective airway reflexesComplicationsfatal aspirationsmall bowel obstructionGastric LavageOrogastric lavage with a large bore tube (36-40 F for adult; no smaller than 22-24 F for children)RARELY recommended not been demonstrated to improve outcome, several risksMight be considered: VERY early or after very dangerous ingestions (colchicine, arsenic)Ensure airway protectedPlace patient in left lateral decubitus position with the head downHave suction available for secretionsPlace tube (tragus-nose-xyphoid) and confirm positionLavage until fluids clearPreferred if done within one hour of ingestion and a rapid deterioration in mental status or vital signs is expected (e.g. TCAs) or if even a small decreased in toxic exposure may be critical (e.g. CaCBs, cochicine, lithium)Preferred over charcoal in patients who have lost their gag reflexes and those who are intubated

22Whole Bowel IrrigationWhole bowel irrigation of the entire GI tract by instillation of large volumes of fluidUsually takes hours Has been used safely in childrenMost useful for substances with delayed absorption ( i.e. extended release ), not amenable to activated charcoal and with body stuffers/packersWhole Bowel IrrigationAccomplished by orally taking (or through NG) large volumes of Nulytely (approved for children and adults), Colyte, or GolytelyAdolescents: mininum of 1.5-2 L/hourChildren: 25 mL/kg/hGive until rectal effluent is clear.Whole Bowel IrrigationContraindications:absent bowel soundsbowel obstruction or perforationunprotected compromised airwayhemodynamic instabilityComplications:vomiting or bloating is frequently seen (often require an antiemetic)rectal irritation

25Forms of EliminationUrine alkalinization- promotes excretion of salicylate, enhances clearance of some drugsDialysisCharcoal HemoperfusionDialysisConsider nephrology consult with dialysis if:S alicylatesT heophyllineU remiaM ethanolB arbituratesL ithiumE thylene GlycolAntidotesPoisonAntidoteAcetaminophenN-acetylcysteineAnticholinergicsPhysostigmineCholinergicsAtropineBenzodiazepinesFlumazenilCarbon monoxideOxygenCyanideAmyl nitrite, sodium nitrite, sodium thiosulfate, hydroxycobalaminDigoxinDigoxin-specific AntibodiesEthylene glycolEthanol/fomepizole, thiamine and pyridoxinePoisonAntidoteHeavy metalsDimercaprol (BAL), EDTA, penicillamineHypoglycemic agentsDextrose, sucrose, octreotideIronDeferoxamine mesylateIsoniazidPyridoxineMethanolEthanol/fomepizole, folic acidMethemoglobinemiaMethylene blueOpioidsNaloxoneOrganophosphatesAtropine, pralidoxamineAvoid physostigmine if TCA ingestion present - has potential to worsen ventricular conduction defects and to lower seizure threshold.

InvestigationsSelect tests only Help confirm diagnosisHelp monitorHelp identify silent killersTox screens not useful in acute managementInvestigationsAll symptomatic patients with unknown ingestion should get electrolytes, glucose, osmolarity, acetaminophen/ASA levels, blood gas, EKGAll suicidal patients should get acetaminophen level (~1:500 patients without a history of APAP ingestion will have a potentially toxic blood level - NYPCC) and ASA levelOther tests based on history, physical, level of suspicionCBC Specific drug levelsUrinanalysisBHCGCalcium, liver function panel

Increased anion gap metabolic acidosis(Na (Cl + HCO3) M ethanol (hx of alcohol abuse, methanol level), metforminU remia (BUN)D KA, AKA, SKA (hx; urine ketones)P araldehyde (distinctive odor)I soniazid (seizure; lactate level)L actic acidosisE thylene glycol (level)S alicylates/solvents (level)Increased Osmolar gap (serum calculated)Two salts and a sticky BUNM annitolA lcoholsD yeG lycerolA cetoneS orbitol

Pitfalls of osmolar gapCannot distinguish between type of toxic alcoholInsensitive in late presentationsNot sufficiently sensitive to exclude small ingestionCannot rule out ingestion based on a normal OGRadio-opaque drugsChloral HydrateOpioid packets (latex)Iron and other heavy metalsNeuroleptics Sustained release tablets/SalicylatesECGFindings include:Toxicologic tachcyardia/bradycardiaQRS wideningProlonged QT (www.qtdrugs.org)

Findings can develop late so obtain serial ECGsCase A 2 year old girl is found playing with his grandmothers pill box. Some pills may be missing and a powder residue is found in the childs mouth.

What medications would most concern you if this child ate just one pill?Small dose toxinsSubstanceMajor symptomSymptom onsetMedicationsBeta-adrenergic antagonists(sustained release)Bradycardia, hypotensionDelayed, up to 24 hoursBuproprion(sustained release)Seizure, cardiovascular collapseDelayed up to 24 hoursCCB (sustained release)Bradycardia, hypotensiondElayed, up to 24 hoursClonidineApnea, bradycardia, hypotension1-2 hoursLomotil (Diphenoxylate/Atropine)ApneaDelayed, up to 24 hoursMethylsalicylate (oil of wintergreen)Metabolic acidosis, pulmonary/cerebral edema1-6 hoursOpioids: extended release preparationsApneaDelayed, up to 24 hoursMethadone1 2 hoursSulfonylureasHypoglycemiaDelayed, up to 24 hoursTheophyllineSeizure, hypotensionDelayed, up to 24 hoursOther agentsCamphorSeizureMinutes to hoursPesticidesSLUDGEMinutes to hoursToxic alcoholsBlindness, renal failure, metabolic acidosis3 8 hours (ethylene glycol)3 18 hours( methanol)ONE PILL KILLERSCaseA 3 yo male presents to the ED comatose with a GCS of 6. He was found on the bathroom floor. Following stabilization, what is the most immediate course of action?

A. Head CTB. ECGC. Tox screenD. Broad spectrum AbxDONT FORGET SEPSIS/TRAUMA!38