confusing drowsiness

Gayathri 5 year old girl from palakkad woke up at 7AM as usual.
Her usual style on waking up was to sit on the steps in front of her house for a while.
Yesterday, while on sitting and enjoying these moments she called out her mother as she thought something bit her from the small gaps of the stone steps.
Both parents were workers staying in a thatched house with mud bricks and the steps in front was  made of broken stones having enough holes in between.
Her mother searched for a while for anything in the gaps,but she failed to see anything.This happened at 7 AM.
As she could nt find anything she thought it must be some insect sting.
But,
Gradually the pain worsened and she became drowsy within one hour 
She was still responding to calls at that time
She was taken to Palakkad General hospital.
As per records she was noticed to be drowsy, very low heart rate 38 per minute.breathing weak.
GRBS tested on arrival was 111 mg/dl

In view of bite history and her vitals were disturbed resuscitation measures were taken.

• She was put on bag and mask ventilation,
• IV bolus N.Saline,
• Adrenalin IV 
• and Hydro cortisone.

In view of poor respiratory efforts dose of
Atropine followed by Inj. Neostigmine was given.Pulse rate was counted ,38/mt
Did nt get time for detailed evaluation,as in any case like this.
Considering possibility of envenomation 20 vials of ASV administered taking all precautions.Pulse rate picked up.
In view of unexplained bradycardia possibility of scorpion bite was considered from there and a dose of Prazozin 2.5 mg 1/3 tab was administered orally.
As she had documented fever first dose of injection ceftriaxone was administered.
After this she was referred to us

Discussion

Perfectly normal child progressive alteration of sensorium coming with shock and irregular breathing the possibilities considered by the doctor must be

1. Bite/sting with envenomation
2. Poisoning (ingested,inhaled or whatever means)
3. Trauma.
4. Metabolic problems 

( Please note the words envenomation and poisoning used here. We all use the word 'Poisoness snake'and  poisoning in all cases of bites and stings which is better avoided)

In this case rapid deterioration with local edema, possibility of bite with envenomation is high in the list.
As the patients vitals were compromised waiting for 20 mt WBC wont be practical.

Occasionally we have to take a decision for ASV especially in case of purely neurotoxic envenomations spending 20 minutes on WBCT is dangerous decision.We can take decision based on clinical grounds only.

Three major snakes causes evidence of neurotoxicity in our setup.

1. Cobra
2. Krait
3. Russel viper. All of us are aware of hematotoxicity,kidney injury of vipers. In the same context if neurotoxicity also is consider Russels viper.  

• Saw scaled viper is not common in kerala, where neurotoxicity wont occur.Among the vipers we encounter
• Hump nose viper very commonly in kerala which causes more of hematotoxicity but no neurotoxicity,Rarely this veriety causes renal damage. 
• Another rare item is Malabaricus veriety which again is not that common.

In this case as the breathing and circulation was compromised this was right decision even in a situation where no snake was found.

But what about the Prazosin ? Is it Justified ?

Tachy or bradycardia may occur in snake bite also, but wide fluctuation of pulse rate and blood pressure (autonomic storm) is typical of scorpion bite. 

Here at this stage, there were not many supporting points at this age to support scorpion. But considering the situation from where bite/sting happened and severe  bradycardia in a context of shock considering this treatable entity and adminstering singel dose of Prazosin is definitely right decision. ( It was administered after stabilization and ensuring the blood pressure.

She was bought to our PICU at 1.30 pm.

• As her breathing was normal she was extubated.Most probably the breathing recovered after short period only.
• She was drowsy GCS 12/15.
• Breathing normal 32/mt
• Pulse 142/mt ,good volume.Periphery warm.
• Blood Pressure 90/60 mm  of Hg.

She had edema at the level of right ankle. No bite marks visible.

Mother said there was a point with doubtful oozing of blood from the site. 

This was the same site where the kid pointed as the site of initial pain

After ensuring her vitals more history we got from mother

• She had low grade fever and cough for the last two days, 
• but was not on any medications. She was not sick during the previous day. 
• There was no significant illness in the past
• No history of trauma. 
• Chances of intake of drug / other poisons  also considered

CNS EXAMINATION

• Drowsy, arousable but was irritable on waking up 
• On opening eyes , no ptosis, eyeball movement full.
• Pupils were normal and reacting 
• Fundus could not be examined. 
• Other cranial nerves normal
• Tone,reflexes were normal in all four limbs
• Plantar flexor
• No signs of meningeal irritation

No fang marks,
but significant edema.
As the mother was doubtful about bleeding we re checked with hand lens, No puncture mark seen.
Fang mark does nt mean much in case of snake bite.
Presence of marks looking like fang may mislead another injury for snake bite or the otherway , especially in a case of Krait bite , where there need not be a mark or local reaction at all 
Any injury may be mistaken for fang mark
There need not be fang mark in case of snake bite especially in case of Krait bite.
In this case pain was mild.

At admission, investigations showed

•  TC               11,300,
•  P                  76%       ,L12%     ,M 12%, 
• Hb-               12.7 gram/dl 
• ESR-             20mm ,
• PT-               13seconds &   (Control -13 seconds )
•  INR              1,
• APTT            32.9 seconds &  ( Control -32 sec ), 
• ,Urea-           25, 
• creat-            0.5, 
• Na-               138, 
• K-                  3.4.
• SGOT            57,
• SGPT            27,
• T. bilirubin   Direct -0.4mg/dL.

Discussion

Referring doctor considered likely conditions and intervention was in the right time,ensured transfer in the proper manner.

If it is snake bite, anti snake venom 20 vials already given and kids vitals stable except the sensorium.

Few points were difficult to explain.

Neurotoxic envenomation with all the classes of snake bite causes LMN type weakness, predominantly in the cranial nerve territory, of course when the weakness advances paralysis of whole limbs respiration ll ensue.

Most of the cases patients awareness maintained till the end,making the death horrible (for the patient)

In our case the paradoxic situation prevalied, Alteration of sensorium dominated , but there was no weakness in the cranial nerve territories or limbs. No ptosis,

In a patient with neurotoxicity it is difficult to assess the sensorium i agree.But here it was easy as there was nothing modifying the expression as there was no motor weakness.

When a patient with envenomation is drowsy ( where it is easy to assess, eg hematotoxic bite) we consider the following possibilities 

1. Intracranial bleed , ischemia. Both can occur in viper bite
2. Secondary to effects on systems, eg renal failure,electrolyte abnormalities etc
3. Consider another diagnosis, Consider case scenario. 

This is very likely to happen if we are biased by the history.

So, if the response is not as expected, if any clinical findings look odd consider other differential diagnosis. 

May be we ll be missing other possibilities few of which may be eminently treatable and precious time wasted. Eg diabetic keto -acidosis,or another poisoning.

Here most of the other differentials were considered, ruled out from investigations.

Possibilities remaining were 

• CNS infections 
• Poisoning. few of the poisons causes changes in pulse and blood pressure by direct injury to heart or autonomic disturbances. 

But the 'toxidrome' was not fitting with any of the usual poisoning. 

We were reminded of the features of NIPAH one year back.'Combination of respiratory signs and symptoms,encephalitis,and autonomic disturbances' we should consider this entity.

Very thought of this few of us became pale. but remained calm.

In case this turned out to be one of the infections likely to be transmitted, all of us and many must have already got it.None  of us took precautions in the closed environment of our ICU setting of course universal precautions when attending such a case is ideal.

So next moments were arguments for and against that possibility 

1. Why should be a local reaction?
2. Will it start all of a sudden, progressing over few hours

Yes,
possibility is less.This is a wild thought.

So we decided to do lumbar puncture and an imaging 

CT done was normal 

Fundus was normal  

Lumbar puncture done which yielded

• clear CSF with normal pressure 
• CSF , showed no cells,
• protein -   21 mg/dl,
• sugar -      76 mg/dl  Blood sugar 118 mg/dl),
•  culture was then sterile. CSF 
• sent for viral study.

Repeat PT ,INR remained normal.

She was put on mannitol,
continued injection ceftriaxone 
continued  monitoring 

Over time the pulse rate remained high,blood sugar values remained on the higher side
This combination was supporting the possibility of scorpion.
We decided to continue Prazosin
She was given four more doses of Prazosin, monitoring the pulse ,blood pressure and blood sugar.
child's sensorium improved within 24 hrs, became active and alert.

Previous experiences of scorpion bites

During our childhood days  scorpions and centipede of different types were plenty,  sting was very common. 

I never thought a sting from  a scorpion cause problems during my student days or post graduate days,till i joined as a teacher here in eighties.

In late eighties we had a bad experience in Thrissur, when a scorpion bite case died.Then we noticed the wide fluctuation of blood pressure in that case.

Later one more case died in late nineties. 

In 2000 i came to know about the wonder drug Prazosin from Dr Mahadevans article. In fact Lot of work in this area by Dr.Bavaskar and pondicherry people.

Since we started using Prazosin early in scorpion stings we did nt loose any child.

I used to attend case discussions in Clinical club in General medicine.

Remember a middle aged man dying developing MI following scorpion and another developing stroke.

Remembering that case we considered possibility of stroke in our case as a reason for unexplained drowsiness. But CT was normal 

Priapism as a manifestation of Scorpion sting

Priapism is not common in pediatric age group. 
Ischemic type of priapism can occur mainly in hematological conditions in this age group. Eg sickle cell anemia and lekemia. 

Drugs may cause it in adults. but rare in this age group

If a patient is bought with priapism of recent onset consider scorpion sting as a reason.
This is common in Tamil nadu.  Have seen a presentation by Thankavelu sir. 

I did nt have personal experience with this entity'

Our girl  was discharged two days back
This case is presented to highlight how atypical presentation of a common case may mislead in case management)

(Thanks to Dr.Divya and Dr. Sameeha, my post graduate students for helping me to prepare this note)