Monsoon season is coming. According to the studies, snake bites increase during monsoon time. They show too that more rainy years correlate to more bites.
So it is time to be ready for SnakeBite First Aid.
Related to First Aid there is plenty of literature, videos, webs and blogs talking about snakebites and first aid. Many, many with still giving confusing or wrong information.
Recently I went through some training material for field workers that still advises to "Tie a cloth tightly a little above the snake bite and give a cut on the bitten area to squeeze out blood to remove the poison. Do not let the person sleep". The other two advices consisting on "do not waste time running after the snake and do not consult snake charmers, ojhas and traditional healers, rather take the person the the health centre immediately" are absolutely correct. The women that will have these trainings will try to do all her best and later on they will train other people based on this nowadays incorrect notions. And like that many YouTube videos and Blogs and TV soap operas...
Let's first set the frame with a reference document: The WHO Guidelines for the Management of Snakebites published on 2016 specifically for the South East Asian Region. The idea is to present the guidelines and after, see what the literature has to say about the different points mentioned. Let's go!
GUIDELINES FOR THE MANAGEMENT OF SNAKEBITES
WORLD HEALTH ORGANIZATION 2016
http://apps.searo.who.int/PDS_DOCS/B5255.pdf?ua=1
First-aid: most of the familiar methods for first-aid treatment of snakebite, both western and “traditional/herbal”, have been found to result in more harm (risk) than good (benefit) and should be firmly discouraged. However, in many communities, traditional therapists and their practices are respected and it is important to initiate a dialogue with these practitioners, perhaps through anthropologists, to encourage their understanding and cooperation in the timely referral of envenomed patients to medical care at the hospital or dispensary.
Recommended first-aid methods emphasize
1) reassurance,
2) application of a pressure-pad over the bite wound,
3) immobilization of the bitten limb and
4) transport of the patient to a place where
they can receive medical care without
delay.
BACKGROUND:
Incidence of snakebite varies diurnally and
seasonally. It is highest during agricultural
activities and seasonal rains.
Most bites are inflicted on the feet and ankles of bare-footed agricultural workers who tread on snakes inadvertently while walking in the dark or working in fields and plantations. Snake species differ in their inclination to strike when disturbed. Notoriously “irritable” species include Russell’s and saw-scaled vipers. Cobras and kraits enter human dwellings. Kraits bite people who are asleep on the ground at night. On average, about 50% of bites by
Most bites are inflicted on the feet and ankles of bare-footed agricultural workers who tread on snakes inadvertently while walking in the dark or working in fields and plantations. Snake species differ in their inclination to strike when disturbed. Notoriously “irritable” species include Russell’s and saw-scaled vipers. Cobras and kraits enter human dwellings. Kraits bite people who are asleep on the ground at night. On average, about 50% of bites by
venomous snake cause no envenoming
(“dry bites”), a figure ranging 5-80% with
different species.
Snakebite epidemics follow flooding, cyclones and invasion of snakes’ habitats for road building, irrigation schemes and logging. These activities cause long term changes in climate and ecology and encourage influx of human settlers.
Males are more often bitten than females. Peak incidence is in children and young adults. Pregnant women and their fetuses are at increased risk of dying. Snakebite is an occupational disease of farmers, plantation workers, herders, hunters, fishermen, fish farmers, snake restaurant workers and snake charmers.
Snakebite epidemics follow flooding, cyclones and invasion of snakes’ habitats for road building, irrigation schemes and logging. These activities cause long term changes in climate and ecology and encourage influx of human settlers.
Males are more often bitten than females. Peak incidence is in children and young adults. Pregnant women and their fetuses are at increased risk of dying. Snakebite is an occupational disease of farmers, plantation workers, herders, hunters, fishermen, fish farmers, snake restaurant workers and snake charmers.
INDIA: CONTROVERSIAL NUMBER OF SNAKEBITES
Registrar General of India’s “Million Death Study” assigned causes of all deaths in about 7000 randomly chosen sample areas, each with a population of about 1000 throughout the whole country. Verbal autopsy (questioning bereaved relatives and neighbours about the circumstances of the deceased’s death), proved reliable for an event as distinctive, dramatic and memorable as snakebite fatality. Results were independent of hospital underreporting and were nationally representative. Direct estimate of deaths attributable to snakebite in 2005 was 46 000 (99%CI 41 000-51 000), (1 snakebite death for every 2 HIV/AIDS deaths). Snakebites caused 0.5% of all deaths, 3% in 5-14 year-olds. 97% died in rural areas, only 23% in health facilities. The highest numbers of deaths were in Uttar Pradesh (8,700), Andhra Pradesh (5,200), and Bihar (4,500).
Registrar General of India’s “Million Death Study” assigned causes of all deaths in about 7000 randomly chosen sample areas, each with a population of about 1000 throughout the whole country. Verbal autopsy (questioning bereaved relatives and neighbours about the circumstances of the deceased’s death), proved reliable for an event as distinctive, dramatic and memorable as snakebite fatality. Results were independent of hospital underreporting and were nationally representative. Direct estimate of deaths attributable to snakebite in 2005 was 46 000 (99%CI 41 000-51 000), (1 snakebite death for every 2 HIV/AIDS deaths). Snakebites caused 0.5% of all deaths, 3% in 5-14 year-olds. 97% died in rural areas, only 23% in health facilities. The highest numbers of deaths were in Uttar Pradesh (8,700), Andhra Pradesh (5,200), and Bihar (4,500).
INDIA: MEDICALLY IMPORTANT SNAKES
The most important snake species from a medical point of view are given according to the following definitions (WHO, 2010):
CATEGORY 1: Highest Medical Importance - highly venomous snakes that are common or widespread and cause numerous snakebites, resulting in high levels of morbidity, disability or mortality.
CATEGORY 2: Secondary Medical Importance - highly venomous snakes capable of causing morbidity, disability or death, but for which (a) exact epidemiological or clinical data are lacking or (b) are less frequently implicated because of their behavior, habitat preferences or occurrence in areas remote from large human populations.
“The big four” medically important species had been considered to be Naja naja, Bungarus caeruleus, Daboia russelii and Echis carinatus but other species have now been proved important in particular areas, such as Naja oxiana (north), N. kaouthia (north east), Hypnale hypnale (south-west coast and Western Ghats (Joseph et al., 2007)), Echis carinatus sochureki (Rajisthan) (Kochar et al., 2007) and Trimeresurus malabaricus (Hassan District, Mysore, Karnataka, Kerala).
Bites by non-venomous species such as checkered keelback/Asiatic water snake (Xenochrophis piscator) are common and may cause confusion among medical staff and lead to inappropriate antivenom treatment.
Cat 1:
Elapidae: Bungarus caeruleus; Naja kaouthia (east), Naja naja (throughout);Viperidae: Daboia russelii; Echis carinatus; Hypnale hypnale (south-west) |
Cat 2:
Elapidae: Bungarus fasciatus, Bungarus niger, Bungarus sindanus, Bungarus walli; Naja oxiana (north west), Naja sagittifera (Andaman Islands); Ophiophagus hannah (south, north-east, Andaman Islands);Viperidae: Trimeresurus (T.) albolabris (northeast); Trimeresurus (T.) erythrurus (northeast); Trimeresurus (T.) purpureomaculatus (east); Trimeresurus (Craspedocephalus) malabaricus (south-west), Trimeresurus (Craspedocephalus) gramineus (south India, Andaman & Nicobar Islands), Macrovipera lebetina (north) |
There is variation in the pattern of syndromes across India, with predominance of haemotoxic viper bites in south India and neurotoxic elapid bites in north India.
Syndrome-species correlation studies in Tamil Nadu suggest the validity of the main syndromes in identifying the four main venomous snakes in this geographical region:
- Haemotoxicity without acute kidney injury (Echis carinatus);
- Haemotoxicity and neurotoxicity with or without renal failure (Daboia russelii);
- Neurotoxicity with local swelling (Naja naja); and
- Neurotoxicity without local swelling (Bungarus caeruleus).
5.2.1 Early symptoms and signs
Following the immediate pain of mechanical penetration of the skin by the snake’s fangs, and the fear associated with such a terrifying experience as being bitten by a snake, there may be increasing local pain (burning, bursting, throbbing) at the site of the bite, local swelling that gradually extends proximally up the bitten limb and tender, painful enlargement of the regional lymph nodes draining the site of the bite (in the groin - femoral or inguinal, following bites in the lower limb; at the elbow or in the axilla following bites in the upper limb). However, bites by kraits, sea snakes and Philippine cobras may be virtually painless and may cause negligible local swelling. Someone who is sleeping may not even wake up when bitten by a krait and there may be no detectable fang marks or signs of local envenoming. (Beware: Abdominal pain is often an early and only symptom of krait bite!)
Following the immediate pain of mechanical penetration of the skin by the snake’s fangs, and the fear associated with such a terrifying experience as being bitten by a snake, there may be increasing local pain (burning, bursting, throbbing) at the site of the bite, local swelling that gradually extends proximally up the bitten limb and tender, painful enlargement of the regional lymph nodes draining the site of the bite (in the groin - femoral or inguinal, following bites in the lower limb; at the elbow or in the axilla following bites in the upper limb). However, bites by kraits, sea snakes and Philippine cobras may be virtually painless and may cause negligible local swelling. Someone who is sleeping may not even wake up when bitten by a krait and there may be no detectable fang marks or signs of local envenoming. (Beware: Abdominal pain is often an early and only symptom of krait bite!)
6.2 First-aid treatment
First-aid treatment is carried out
immediately or very soon after the bite,
before the patient reaches a dispensary
or hospital. It can be performed by the
snakebite victim himself/herself or by
anyone else who is present and able.
Unfortunately, most of the traditional,
popular, available and affordable first aid
methods have proved to be useless or
even frankly dangerous. These methods
include: making local incisions or pricks/
punctures (“tattooing”) at the site of the
bite or in the bitten limb, attempts to suck the venom out of the wound, use of (black) snake stones, tying tight bands
(tourniquets) around the limb, electric
shock, topical instillation or application of
chemicals, herbs or ice packs. Local people
may have great confidence in traditional
(herbal) treatments, but they must not be
allowed to delay medical treatment or to
do harm.
Aims of first aid
-
reassure the snakebite victim
-
attempt to delay systemic absorption of venom
-
preserve life and prevent complications before the patient can receive medical care at a dispensary or hospital
-
control distressing or dangerous early symptoms of envenoming
-
arrange the transport of the patient to a place where they can receive medical care
- ABOVE ALL, AIM TO DO NO HARM!
6.2.2 The danger of respiratory paralysis and shock
The greatest fear is that a snakebite victim
might develop fatal respiratory paralysis
or shock before reaching a place where
they may be resuscitated (Looareesuwan
et al., 1988).
This risk may be reduced by:
- Speeding up transport to hospital,
- Improving free ambulance services (Gimkala et al., 2016)
- Recruiting village-based motor cyclist volunteers who transport the victim propped upright between the driver in front and a supporting pillion passenger behind.
This has proved effective in villages in the
Nepal Terai (Sharma et al., 2013) (Figure
73)
Medical workers can be trained in airway management and assisted
ventilation. The special danger
of rapidly developing paralytic envenoming
after bites by some elapid snakes has
prompted the use of pressure-bandage
immobilization (Sutherland et al., 1979)
and pressure-pad immobilization (Anker
1982; Tun-Pe et al.,1995b )(ANNEX 4).
Pressure bandage immobilization requires
equipment (long elasticated bandages and
splints) (Canale et al., 2009; Currie et al.,
2008 ) and skill.
As far as the snake is concerned:
Do not attempt to kill it as this may be
dangerous. However, if the snake has
already been killed, it should be taken to
the dispensary or hospital with the patient
in case it can be identified. However, do
not handle the snake with your bare hands as even a severed head can
bite!
Several close-up mobile ‘phone
images of the snake should be taken if
possible to allow expert identification.
MOST TRADITIONAL FIRST-AID
METHODS SHOULD BE DISCOURAGED:
THEY DO MORE HARM THAN GOOD!
6.2.3 Recommended first-aid methods
1.- Reassure the victim who may be very anxious.
Reassurance will drive away their fear and excitement, slow the patient’s heart rate and reduce the spread of venom. Grounds for reassurance include the possibility of a “dry bite” even if the snake was venomous, the usually slow evolution of severe envenoming allowing time for treatment, and the effectiveness of modern medical management of snakebite.
Reassurance will drive away their fear and excitement, slow the patient’s heart rate and reduce the spread of venom. Grounds for reassurance include the possibility of a “dry bite” even if the snake was venomous, the usually slow evolution of severe envenoming allowing time for treatment, and the effectiveness of modern medical management of snakebite.
2.- Immobilize the whole of the patient's body
by laying him/her down in a comfortable and safe position, ideally in the recovery position (lying prone on the left side in case vomiting threatens to result in aspiration), and immobilize the bitten limb with a splint or sling. Any movement or muscular contraction, even undressing or walking, will increase absorption and spread of venom by squeezing veins and lymphatics.
by laying him/her down in a comfortable and safe position, ideally in the recovery position (lying prone on the left side in case vomiting threatens to result in aspiration), and immobilize the bitten limb with a splint or sling. Any movement or muscular contraction, even undressing or walking, will increase absorption and spread of venom by squeezing veins and lymphatics.
3.- Apply pressure-pad immobilization
Unless the possibility of an elapid bite can confidently be excluded, apply pressure-pad immobilization (See ANNEX 4), or, if the necessary equipment and skills are available, pressure-bandage immobilization. In Myanmar, the pressure-pad method has proved effective in reducing spread of venom in victims of Russell’s viper bite (Tun Pe et al., 1995b). Pressure-bandage immobilization has not become widely used in this Region, because provision of the necessary equipment (long, wide elasticated bandages), training and skills required to apply it safely and reliably have proved impossible to achieve. The pressure-pad immobilization method is preferred and recommended as being simpler and more practicable.
Unless the possibility of an elapid bite can confidently be excluded, apply pressure-pad immobilization (See ANNEX 4), or, if the necessary equipment and skills are available, pressure-bandage immobilization. In Myanmar, the pressure-pad method has proved effective in reducing spread of venom in victims of Russell’s viper bite (Tun Pe et al., 1995b). Pressure-bandage immobilization has not become widely used in this Region, because provision of the necessary equipment (long, wide elasticated bandages), training and skills required to apply it safely and reliably have proved impossible to achieve. The pressure-pad immobilization method is preferred and recommended as being simpler and more practicable.
4.- Avoid any interference with the bite wound
(incisions, rubbing, vigorous cleaning, massage, application of herbs or chemicals) as this may introduce infection, increase absorption of the venom and increase local bleeding.
(incisions, rubbing, vigorous cleaning, massage, application of herbs or chemicals) as this may introduce infection, increase absorption of the venom and increase local bleeding.
CAUTION Delay the release of tight
bands, bandages and ligatures: if the
patient has already applied these very
popular methods of first-aid, they should
not be released until the patient is under
medical care in hospital, medical staff and
resuscitation facilities are available and
antivenom treatment has been started
(Watt et al., 1988) see Caution below.
Tight (arterial) tourniquets must
never be recommended or condoned!
Traditional tight (arterial) tourniquets. If applied tightly around the upper part of the limb, these bands, bandages or
ligatures are extremely painful as the limb
becomes ischemic and are very dangerous
if left in place for long periods. Many
gangrenous limbs have resulted!
6.3 Transport to hospital
Emergency Helpline Numbers
Linkage with an emergency helpline
number (e.g. in India 108 see http://
www.emri.in/) can speed up the
transport of a patient to a higher
referral centre when emergency
treatment is required. This will decrease
delays in accessing emergency care and
reduce mortality. Information about
helpline numbers could be widely
disseminated.
The patient must be transported to a
place where they can receive medical
care (dispensary or hospital) as quickly,
but as safely and comfortably as
possible. Any movement, but especially
movement of the bitten limb, must be
reduced to an absolute minimum to
avoid increasing the systemic absorption
of venom. Any muscular contraction
will increase spread of venom from the
site of the bite in veins and lymphatics.
Where a conventional motor vehicle
ambulance is not available or feasible,
stretcher, bicycle, motorbike (Pateland Ekkiswata, 2010) - by recruiting
village-based motorbike owners/
cyclists (Sharma et al., 2013),
cart, horse, train or boat may have to
be considered, or the patient can be
carried (e.g. using the “fireman’s lift”
method). If possible, patients should be
placed in the recovery position during
transit, in case they vomit.
THE ANNEX 4
Pressure-immobilization methods
Bites by cobras, king cobras, kraits, Australasian elapids or sea snakes may lead, on rare occasions, to the rapid development of life-threatening respiratory paralysis. This paralysis might be delayed by slowing down the absorption of venom from the site of the bite. The following techniques are currently recommended:
1) Pressure-pad plus immobilization
(Anker et al., 1982; Tun-Pe et al., 1995)
Ideally, an elasticated bandage,
approximately 10 – 15 cm wide and at least 4.5 metres long should be used (Canale et
al., 2009). If that it not available, any long
strips of material can be used. The bandage
is bound firmly around the entire bitten
limb, starting distally around the fingers or toes and moving proximally, to include a rigid splint. The bandage is bound firmly
(at a pressure of 50-70 mmHg), but not
so tightly that the peripheral pulse (radial,
posterior tibial, dorsalis pedis) is occluded
or that the patient develops severe
(ischaemic) pain in the limb.
Instead of the pictures, here is a link to the Australian Venom Research Unit showing how to do a pressure-bandage plus immobilization
Bites by cobras, king cobras, kraits, Australasian elapids or sea snakes may lead, on rare occasions, to the rapid development of life-threatening respiratory paralysis. This paralysis might be delayed by slowing down the absorption of venom from the site of the bite. The following techniques are currently recommended:
1) Pressure-pad plus immobilization
(Anker et al., 1982; Tun-Pe et al., 1995)
A rubber and/or folded material pad
approximately 5 cm square and 2-3 cm
thick is placed directly over the bite site
anywhere on the body and bound in place
with a non-elastic bandage at a pressure
of at least 70 mmHg.
2) Pressure-bandage plus immobilization
Sutherland et al., 1979 ; Sutherland and Tibballs, 2001)
2) Pressure-bandage plus immobilization
Sutherland et al., 1979 ; Sutherland and Tibballs, 2001)
Instead of the pictures, here is a link to the Australian Venom Research Unit showing how to do a pressure-bandage plus immobilization
 |
| Pressure-bandage immobilization technique |
ॐ लोकाः समस्ताः सुखिनो भवन्तु ॥
Om Lokah Samasthah Sukhino Bhavantu
May all beings everywhere be happy and peaceful
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