©JAPI • VOL.56 • FEBRUARY2008 www.japi.org 121
Case Report
Locked-in Syndrome in Snakebite
S Prakash*, C Mathew**, S Bhagat**
Abstract
Two young patients are described who made complete recovery from locked-in syndrome (LIS) after
snakebites.LISwasapresentingfeatureinapatientofpresumedsnakebitewhoshowedcompleteresponse
topolyvalentAnti-snakevenom(ASV).Thiscasesuggeststhatelapidsnakebiteshouldbesuspectedin
unresponsivepatientfoundinearlymorninginendemicareasofsnakebiteinmonsoonseason.Thesecond
casewasadmittedincompleteLISstatewithhistoryofrapidlyprogressiveptosis,diplopia,ophthalmoplegia,
bulbarsymptomsandquadriparesis,6hoursaftersnakebite.CompleteimprovementbyASVinsecond
patienthighlightstheneedofdifferentiationofcompleteLISfromcomaandbraindeathinpatientofsnake
bite,asformerhavegoodprognosis.©
INTRODUCTION
L
ocked-in syndrome (LIS) is characterized by
qadriparesis and anarthria in conscious patient.
Patient can be communicated by eye movement and
blinking.CommunicationisnotpossibleintotalLIS.
1
LIS may be either of central, usually ventral pons
1
,
or of peripheral origin.
2
Diagnosis of central cause is
important for rehabilitation purpose, as even limited
physicalactivitycanimprovequalityoflife.
1
Knowing
the peripheral causes is very important, as one may
make erroneous diagnosis of brain death in a patient
withcompleteLISduetofulminantpolyneuropathyand
severeneuromuscularjunctionBlockade.
2,3
Intwocase
reports,wediscusstheimportanceofLISinpatientsof
snakebiteandreviewtheliterature.
CASE REPORTS
Case-1
A40yearsmalewasbroughttotheemergencyroom
inunresponsivestatewithnosignifcantpasthistory.
In early morning patient did not show any response
whenhiswifetriedtomakehimawake.Atpresentation,
patienthadnomotorresponsetopainfulstimuli.There
wasptosis,nospontaneouseyemovementandabsent
oculocephalicandoculovestibularrefexes.Deeptendon
refexes and planter refexes were absent. Pupil was
of3mmsizewithsluggishreactiontolight.Physical
examinationrevealednoabnormality.Hisrespiratory
effort was sluggish. Endotracheal intubation was
performedandpatientwasmechanicallyventilated.A
provisionaldiagnosisofstrokewasmade,butMRIBrain
*AssistantProfessor;**JuiorResident,DepartmentofNeurology,
MedicalCollege,Baroda,Gujarat.
Received:10.10.2007;Accepted:29.10.2007
was normal. Hematological examination and blood\
serum biochemistry (sugar, creatine, liver function
tests, electrolytes, and thyroid profles) were within
normal limits. Chest X-ray and cerebro spinal fuid
(CSF) examinations did not reveal any abnormality.
The electroencephalograph showed alpha and theta
activitywithnoepileptiformdischarges.Furthercareful
examinationsofskinrevealedreddishspotoverback
ofchest.Itwasnottypicalfangmarkofsnakebite,but
patientwasgiveninjectionpolyvalentASV.Wenoticed
spontaneouseyemovementwithinanhouroftreatment.
He communicated with eye movement. There was
completeimprovementofptosisandophthalmoplegia
inabout30hours.Patientwasextubatedafter3days.
Proximal muscle weakness took 7 days to improve
completely.Thepatientcouldrememberwelltheperiod
whenhewasunresponsive.Hedidnotgivehistoryof
anypossiblesnakebiteortoxinanddrugexposure.
Case 2
A 25 years old male was bitten on toe by an
unidentifed snake 8 hour prior to his admission. He
wasbroughttoemergencyroominunconsciousstate
with history of rapidly progressive ptosis, diplopia,
dysphagia,dysarthria,dyspnoea,andweaknessofall
fourlimbs.Patientwasunresponsivetopainfulstimuli.
Lightrefex,oculocephalicrefex,oculovestibularrefex,
deep tendon reflexes and superficial reflexes were
absent. Swelling at bite site was noted. Patient was
mechanically ventilated because of poor respiratory
efforts.Hematologicalexaminationsandblood/serum
biochemistrywerewithinnormallimits.Aprovisional
diagnosisofsnakebitewithhypoxicencephalopathywas
made.InjectionpolyvalentASVwasstarted.Therewas
spontaneouseyemovementafter6houroftreatment
andpatientcommunicatedwitheyemovement.Patient
improvedcompletelyin5days.Patientwasabletorecall