QUIZ3rdJune2020(answersbelow)

1. Whataretheclinicalfeaturesofhydroxychloroquinetoxicity?

2. WhataretheECGchangesinsodiumchannelblockade?

3. Whatisthemanagementofhydroxychloroquinetoxicity?

4. Whatiscinchonism?

5. DescribeandinterpretthefollowingECG.

QUIZanswers3rdJune2020

1. Whataretheclinicalfeaturesofhydroxychloroquinetoxicity?

o Decreasedlevelofconsciousness/seizures

o Cardiogenicshock/arrhythmias/wideQRSandQTprolongation

o Hypokalaemia

Ingestionofjustonetabletispotentiallylethalinachildlessthan6yearsold

2. WhataretheECGchangesinsodiumchannelblockade?

o QRS>100msinleadII

o RightaxisdeviationofterminalQRS

§ TerminalRwaves>3mminaVR

§ R/Sratio>0.7inaVR

3. Whatisthemanagementofhydroxychloroquinetoxicity?

• IntubationatfirstsignofcardiotoxicityordecreasedLOC

• HyperventilationtolownormalpCO2

• Serumalkalinisation–Sodiumbicarbonate1-2mmol/LforpH>7.5

• IVfluidsjudiciously

• Adrenalineasvasopressorofchoice

• Benzodiazepinesforseizures

• Potassiumforhypokalaemia,rememberingthattotalbodypotassiumis

normal

• Activatedcharcoalupto4hoursonceairwayprotected

• Highdosediazepaminfusionisproposedasanantidotebutunproven

Patientswhoareasymptomatic6hourspostingestioncanbedischarged

Allchildrenshouldbeadmittedforobservation

4. Whatiscinchonism?Cinchonismistheclinicalmanifestationofquininetoxicityofnausea,vomiting,

alterationsinhearing,tinnitusandvertigo.Itoccursearlyfollowingoverdoseand

resolvesatbloodquinineconcentrationfalls.

5. DescribeandinterpretthefollowingECG.

Rate 71/minRegular

Pwaves Normalmorphology,allconducted

PRinterval Short0.10sec

QRS Nodeltawave

Narrow0.10sec

Normalaxis

Morphologynormal

STsegment Isoelectric

Twaves Normal

QTinterval Normal

è ShortPRintervalwithnormalPwavesandnormalQRS

è Lown-Ganong-Levinesyndrome