Thursday 26 June 2014

Cerebral Infract Due to Snake Bite -11th Case reported world wide



By

Dr Sourabh Pathak



This case report describes a Cerebral Infarct following a Russel Viper Bite .
Heamorrhagic complications of Snake bite are well known but thrombotic stroke following snake bite is a very rare occurrence with very few reported cases .
We came across one such rare case of thrombotic stroke in the Emergency Department of Peerless Hospital and B C Roy Research Centre . With this case report we will briefly discuss about various aspects of Thrombotic Stroke following snake bite .

Case Report
On 24-07-2013 a 42 year old man was received in the Emergency Department (ED) of Peerless Hospital and B.C. Roy Research Centre .
The case will be described as per our Emergency Department case management protocol


The Primary ED Survey was remarkable for a airway full of secretions , with bilateral crepts present and a GCS of E 2 M 4 V 2(ie8/15) , with left hemi paresis ,B/L plantar flexor , Pupilary reaction present


¨ Exposure : A small abrasion in right lateral aspect of forehead , no other signs of injury found
BP 140/80 mmHg , HR 90/Min , Spo2 88%, RBS 160 mg/dl , Temp 98 F

Action :
Oxygen started at 6l/min via face mask Rapid Sequence Intubation done to secure the Airway.


AMPLE History
Allergies : None ,
Medications (past ) None ,
Past Medical History : None
Last Meal : Approximately one day ago ,
Events leading to the incident : The incident occurred in a village in Burdawn District one day ago(ie 23/7/13) at about 10 AM .The patient who was a farmer was about to climb a mango tree then he was bitten by a big “Chandra bora” Snake .(local Bengali name for Russel’s Viper ).
Events following the Bite are illustrated below along with the time of each significant event (please see discussion for the


23 /7/ 13 10AM Bite by Russel Viper -à Ran for Help and reached a friend in 10 minutes and said that he has been bitten by a Russel’s viper snake while describing the event and planning what to do( 20 minutes ) the patient developed drooping of eye leads and then slurring of speech and the patient got semiconscious (as per description GCS appeared to be E 3 M5 V 3 ) → Villagers came for help ambulance called


23/7/13 11:30 AM Ambulance came and the patient was transferred to the local Primary Health Center(PHC) without any tourniquet or pressure bandage . In the PHC the patient was given 10 units of Anti Snake Venom and referred to a tertiary center in Kolkata ( approximately 100 km away )


23 /7/ 13 6PM Patient arrived at MS Bangur Institute of Neuro Sciences (a tertiary center in Kolkata ) where a CT Scan of brain was done(See CT plate below ) was done and for some reason the patient was referred to another center at about 11 PM .The patient moved to various hospitals and ultimately came to ED of Peerless Hospital at 11 AM 24 /7/13 during the time of presentation GCS was E 2 M 4 V 2


Following this Secondary survey was carried which was significant for
1 left sided Hemiparesis
2 Small aberration 3 cm in forehead


3 A alleged Fang mark in Left foot (The small black mark surrounded by circle )




CT Brain taken at MS Bangur Hospital one day ago




Other Reports done at ED Peerless Hospital :
20 Minutes Whole Blood test – Negative ,

Hb 11 , TC 8000 , platelets 1,50,000 ,

Na 138 , K 4.5
PT 11 , INR 0.8 ,

Cr 1.4 Urea 35 ,

Urine output : 400 ml in 4 hours


Management :
Management was supportive and Monitoring carried out in the Resuscitation Bay of the ED with IV fluids and ventilator management .But in spite of our best efforts the patient died after 8 hours of arrival to the ED .


Discussion :
From the description of the case it appears to be that this is a snake bite by Russel’s Viper which resulted to a large cerebral infract and ultimately death of the patient . Venomous Snake bites has been traditionally classified into neurotoxic and heamatotoxic though their cardiotoxic , local necrotic effects and anti endothelial effects are well known . However prothrombotic effects of venomous snakes specially cerebral infracts are very rarely reported in medical literature . Our case appears to be one of the rarest of the rare case .
Our review of medical literature revealed that till date there are only 10 cases of cerebral infract reported in medical literature .

Reported by
Year
Snake
Ittyachen AM et al
2012                    
Thalamic infract by Russell’s Viper
2012
Cerebellar infract by Russell’s Viper
2011
Cerebellar and occipital infract by Russell’s Viper
2009
Left MCA territory infract by Russell’s Viper
2009
Bilateral Ant cerebral Artery by Viper 
2008

Bilateral cerebellar and right occipital infarction
2002
Multiple cerebral infract by Bothrops caribbaeus, a species of the Bothrops complex, is found only in the island of Saint Lucia, West Indies.
2000
Left frontal infract by viper
1997
Cerebral infract by Viper
1985
Left cerebral infract by carpet viper (Echis carinatus)



NB
¨ MOSQUERA et all studied 309 patients with complicated Snake Bite ..8 had CVA only one had Infract .
¨ There are also several reported cases of myocardial infraction and one reported case of intestinal infract following viper bite .

Mechanism

The probable mechanism that is generally given to explain cerebral infract following snake bite are interplay between three pathological processes namely Hypovolumia , hypercoagulablity and Vasculitis with vasculitis being the major process initiating a cerebral infract .
¨ Hypovolumia due to snake bite may caused by Vomiting , Sweating and bleeding which leads to a low flow state in the coronary arteries – however this doesn’t appear to be present in our case .
¨ Hypercoagublity is casused by procoagulants in Venom like Arginine,Esterase and Hydrolase
¨ Vasculitis which appears to be the major contributing factor in our case is thought to be caused by Hemorrhagins : component mediated Toxic component of viper Venom which leads to vascular spasm, endothelial damage and increased permeability contributing to vessel occlusion ultimately
leading to Infract.


These three mechanisms appear to expain the classical virchow's triad which describes the three broad categories of factors that are thought to contribute to thrombosis.:Hypercoagulability ,Hemodynamic changes (stasis, turbulence) , Endothelial injury/dysfunction.


It should be noted that had the patient got pressure bandage at an early stage and had the patient be transported earlier to Primary health care centre as suggested by WHO guidelines this event could have been prevented .


Conclusion


Cerebral infraction can be a rare complication of snakebite .