Anatomy And Habits Of Indian Snakes Biology Essay
In the 4th century BC, India was invaded by Alexander the Greats ground forces, which was accompanied by a figure of Macedonian doctors and perceivers.
They were impressed by the accomplishments of the local Ayurvedic practicians, peculiarly in the intervention of serpent bite ( 1 ) . Unfortunately, the bequest of antediluvian accomplishments, experience and wisdom may hold held back instead than encouraged the application of modern scientific research methods to pull off this go oning flagellum of rural life in India ( 2 ) .In India, snake envenomation is a immense public wellness job, but unluckily it has n’t got its due attending.
There is light information on epidemiology and minimum research on anti venom. Most of the quoted figures on serpent bite are infirmary based though most bites occur in small towns and among hapless population, who rely mostly on traditional intervention. Recent Global Snake Bite Initiative of the International Society on Toxicology and by the World Health Organisation, is expected to throw more visible radiation on epidemiology and intervention of serpent bites ( 3 ) .
Of the 3,000 or so snake species that exist in the universe, merely approximately 15 % are deadly. Deadly serpents exist on every continent except Antarctica. In India the ‘Big Four ‘ ( Cobra, Krait, Saw scaled and Russel ‘s viper ) are the cardinal toxicant serpents ( 4 ) .Though the infirmary records show merely 1,300 one-year deceases but a recent Nationally Representative Mortality Survey puts this figure to approx. 45,900 deceases a twelvemonth.
Snakebite remains an underestimated cause of inadvertent decease in modern India. Community instruction, appropriate preparation of medical staff and better distribution of antivenom, particularly in the provinces with the high prevalence, could cut down snakebite deceases in India ( 5 ) .Historical Background: Since clip immemorial serpent has been an object of worship in many states. Harmonizing to Hindu mythology this universe is resting on a many-headed cobra. Lord Vishnu lies on Sheshnag.
The Cobra coils around Lord Shiva. Old Egyptian aristocracy are pictured with cobra goon on their brow. Some civilizations held serpents in high regard as powerful spiritual symbols. Quetzalcoati, the fabulous “ plumed snake ” was worshipped as the “ maestro of life ” by ancient Aztecs of Central America. Some African civilizations worshipped stone pythons and considered the violent death of one to be a serious offense. In Australia, the Aborigines associated a elephantine rainbow snake with the creative activity of life. In Judaic texts, in the old Maya civilisation, in Kundalini yoga, theosophy and in many mediaeval society emblems the universe over, serpents form an indispensable symbol. This shows how confidant has been the historical, societal and fabulous association of serpents with the world and no inquire the cobra is worshipped in India on Naga Panchami twenty-four hours.
Ayurvedic texts written by Vagbhata and Sushruta, have given in just item the categorization of serpents harmonizing to their symptoms and their toxic condition. There are many narratives about constrictors, peculiarly Eunectes murinus in the Amazon and pythons in the E, which are said to hold strangled grownup worlds, these need to be treated with great trade of incredulity ( 6,7,10 ) .In pattern it is merely the toxicant serpents that are of involvement.
Poisoning from snake bite is an of import medical exigency in Africa, South America, India, Pakistan and greater portion of south East Asia.EpidemiologyAs snake bite is non a notifiable unwellness, there is small dependable information on incidence of snakebite in many parts of the universe. Snake bite is an of import occupational hurt impacting husbandmans, plantation workers, Herders, and fishermen. Open-style habitation and the pattern of kiping on the floor besides expose people to bites from nocturnal serpents. Bites are more frequent in immature work forces, and by and large occur on lower limbs. The incidence of serpent bites is higher during the rainy season and during periods of intense agricultural activity ( 6 ) .
Available information shows 30,000-40,000 deceases from snakebites every twelvemonth but this figure likely is an underestimate ( 8 ) , because of uncomplete coverage. Recent planetary estimates suggest 2.5 million bites and 85000 one-year deceases. In India recent published literature suggests annually 45,900 deceases due to toxicant snakebites and 5.6-12.6 deceases per 100,000 population in some provinces appears to be realistic ( 4,5 ) . Upto 80 % of snake bite patients in developing states, first contact traditional practicians, before sing a medical centre ( 6,7,9 ) . Owing to the hold in making hospital many patients die enroute.
Traveling by the fact that around 85-90 % serpents are nonpoisonous and even 50 % of bites by toxicant serpents are dry tallies, figure of snakebites in India are tremendous ( 4 ) . Myanmar likely has highest mortality figure in Asia, where over 70 % bites are by Russell ‘s viper. In India, Maharashtra records the highest figure of snakebites, followed by West Bengal, Tamil Nadu, Uttar Pradesh and Kerala. In Maharashtra entirely, 70 bites per 100,000 population occur annually with 2.
4 per 100,000 mortality. Rajasthan and Jammu part of J & A ; K besides report big figure of viper bites ( up to 95 % of all bites ( 10 ) . During rains and inundations figure of instances shows a steep rise. Most bites occur between 0400 hours to midnight and mere observation that bulk of bites are on lower appendage suggest that serpent is unwittingly trodden upon.In India 2/3rd of bites are due to saw scaly viper, approximately 1/4th due to Russell ‘s and a smaller proportion due to cobra and Krait. In neighbouring Sri Lanka Daboiarussellii histories for 40 % and in Myanmar 70 % of serpent bites ( 11,12 ) .For right epidemiological surveies one requires enzyme-linked immunosorbent check to place antigen and antibody. This permits dependable designation and sensitive quantification of venom antigens and antibody.
Natural antibody is noticeable in serum by one hebdomad of bite, which rises to top out by one twelvemonth and falls to low degrees by 3 old ages, though may be noticeable for up to 40 old ages after bite. Anti snake venom reduces but does n’t get rid of the coevals of antibodies. In some states e.g.
Australia, ELISA is routinely used for designation of toxicant ( 13 ) .Anatomy and HabitSSnakes belong to order Ophidia of the Reptilia general category. Over 3000 species are encountered in the universe of which less than 15 % are toxicant. Most of these are found in tropical and semitropical parts, Australia and throughout USA except in Alaska, Maine and Hawaii. In India 216 species from 9 households are reported of which 52 species from 3 households are toxicant.Most serpents are non-venomous, have no Fangs and belong to colubrid household ; a few colubrids are technically toxicant holding a venom secretory organ connected to a solid Fang at the dorsum of oral cavity.
Bites from back fanged colubrids are by and large harmless to adult male but with some species like African boomslang, Dispholidustypus, serious and even fatal toxic condition has been reported in the serpent animal trainers ( 13 ) . The three households of forepart fanged toxicant serpents are elapids, vipers and sea serpents. Elapids are land serpents with non-mobile 3-5 millimeter long Fangs in grownups. Vipers have 10-30 millimeters long Fangs which are easy to see when erected, but hard to see when folded against upper gum.
Vipers are divided into crotalids or cavity vipers who have heat feeling cavity between oculus and nose and Viperidae which do n’t hold the cavity. Sea serpents have really short immobile Fangs and level rudder like dress suits. There are chiefly 4 toxicant serpents encountered in India i.
e. Cobra, Krait, Saw scaled and Russell ‘s viper. New add-on to ‘Big Four ‘ is Hump-nosed Pit viper ( Hypnale hypnale ) , late being reported from India though existent for more than 100 old ages ( 16 ) .This has been mistaken for Saw Scaled Viper by most. It is identified by larger, triangular caput stoping in a neb with big graduated tables on the caput in contrast to the little graduated tables of proverb scaled viper. The envenomation is manifested by coagulopathy and nephritic failure.
It is reported as one of the most toxicant serpents in India but specific anti venom against this is non available ( 12 ) .Common toxicant serpents found in India are as below ;Viperidae * Saw scaled viper ( Echis carinatus )* Russell ‘s viper ( Vipera russelli )Elapidae * Indian Cobra ( Naja naja )* Common Krait ( Bungarus caeruleus )Crotalidae * Pit ViperHydrophidae * Sea serpentsCobra is 1.2-2.1 metres long while King Cobra may be every bit long as 5.5 metres.
Cobra is normally slate grey to brown. The dorsum of goon may or may non hold a form. They raise their goon when aroused or threatened. They try to avoid world unless they are excessively close or are trodden upon. The distance a cobra can strike in forward way is the tallness its goon rises above the land. Some cobras nevertheless can ptyalize venom upto a distance of 3 metres. This can do inflammation, corneal abrasions/ulcers etc. King cobra is uniformly olive, brown or green with ringlike cross sets of black.
Although it is the largest deadly serpent in the universe but it avoids assailing another deadly serpent for fright of being bitten, therefore it feeds merely on harmless species. Females construct a nest and so lodge the eggs. Liing close by, she guards the nest and is extremely aggressive towards anything which approaches the nest.The male monarch cobra is found in the woods or their locality in the Himalayas, Bengal, Assam and South India.
The common Indian cobra is found in jungles but besides in unfastened state with or without flora ; in gardens, drains, cultivated Fieldss, and populated countries in adult male ‘s propinquity ; in tonss of wood and under rubbish, in loose masonry, crannies of walls and edifice ruins ; in old graveyards, in temples or mosques.It is frequently seen in dark corners of bathrooms, stallss and servant quarters of old cottages. It may be found in old hole of a tree, in ant-hill or a rat tunnel. It can mount trees and swim good. It feeds on rats, mice, toad ; less often on birds or their eggs ; and sometimes on poulets, squirrels, lizards and other serpents. It is normally diurnal in wont but in populated countries it is more nocturnal ( 14,15 ) .
Krait is black or blue black with white narrow crossbands and a narrow caput. It ‘s mean length is 90cm – 150 centimeter. It is found merely in Asia. It is active during dark and passive during the twenty-four hours. It is found in fields, cultivated Fieldss and human habitations.
It has inclination to seek shelter in kiping bags, boots and tents.Kraits are largely found in Eastern India, Assam, Bengal and parts of South India and spots all over the state. There are two assortments, banded and non-banded. Although it has most powerful venom of all land serpents, it is instead diffident and bites human existences least normally ( 13,15 ) .Vipers are so called because they are live-bearing. There are 110 sorts of vipers and all are toxicant. Vipers have wide home bases widening right across the abdomen and little graduated tables on the caput similar to those on the organic structure.
Body is light brown and their dorsum is normally covered with black splodges of upside-down V shaped markers. Some of the cavity vipers have big shield on the caput. Russell ‘s viper or Daboia is a large stumpy snake A?-2 metres long with short tail and characteristic marker as described above. It is cranky. When threatened it coils tightly, hushings and work stoppages with a lightning velocity, that victim has no opportunity of get awaying. Indian cavity vipers are by and large found in hilly countries of Western Ghats and Sunderbans in West Bengal.Russell ‘s viper prefers unfastened state, cultivated Fieldss and bushy or grassy fallow lands.
It is nocturnal in wont. It is normally found in fields of Punjab, Bombay, Madras country and Brahamputravalley ( 4,6,20 ) .Saw scaled viper ( Echiscarinatus ) is found all over India but peculiarly in Western India, Punjab, and around Tiruchirapalli. It prefers unfastened dry bouldery state or waterless deserts.Saw Scaled Viper ( Phoorsa ) is responsible for maximal bites and deceases all over the universe than any other serpent. This little chunky serpent steps 25-60cmand disguises good with the milieus. Colour is light fan with sunglassess of brown, dull red or grey. Its sides have a white or light colored form.
Its caput normally has dark chevrons that start behind the oculus and widen to the rear. It gets its name from the fact it rubs its ain organic structure from sides and produces rasping sound. This ill- treated serpent onslaughts any interloper. It is common in rural colonies, cultivated Fieldss and parts, barns, and stone walls ( 4,14 ) .Sea serpents resemble cobra and its Alliess in construction of their Fangs and most other characters. Most of them are 3-4 ft. long, and a few may achieve a length of 8 pess. Their dress suits are laterally flattened and are sculled in paddle -like manner during swimming.
Most sea serpents are covered with little unit of ammunition graduated tables and lack the hypertrophied ventral graduated tables found in tellurian species. The anterior nariss are valvularand hey can be closed when snake submerges- and may be displaced towards the top of the caput. Excess salt from the sea H2O and diet is excreted through particular secretory organs in the serpent ‘s oral cavity. Deadly sea serpents largely inhabit the Waterss of Australia, Indonesia, Southeast Asia and India. Of the more than 50 species some are many times more toxicant than land serpents, with venom 10-40 times more powerful than that of cobra.
Except for a individual species found in brook and river estuaries sea serpents are all toxicant. They nevertheless have a narrow gape and seldom seize with teeth effectively.Their bite is comparatively painless and, surprisingly really low per centum of patients suffer important envenomation during the onslaught. In a nose count in Malay Peninsula less than 25 % developed characteristics of toxic condition and a little per centum became critically sick ( 4,12,14 ) .Snakes have a good sensory perceptual experience with crude ears. Their vision is limited to few metres merely, with better sharp-sightedness for traveling objects. Lower jaw is a brace of castanetss joined together centrally by an elastic ligament which does n’t joint with upper jaw therefore enabling the serpent to get down its quarry as a whole.
Fangs are modified dentitions on pre upper jaw. Venom is secreted from parotid secretory organs and is meant to immoblise the little animals like rat. Man is an guiltless coincident victim. Bite is a good coordinated act affecting motion of caput and organic structure. It involves coordinated placement of caput, gap of oral cavity, onslaught by forward push of organic structure and caput, piercing the tegument by Fangs and shooting the venom while the lesion is deepened by contraction of temporalis musculus. Vipers have holes at the tip of Fangs while elapids have troughs in the Fangs ( 14,15 ) .Designation of Poisonous SnakesMost of the bites are by nonpoisonous serpents, but the intense fright of serpent bites may do ague panic reaction or feeling of impending decease.
If the patient has brought serpent to the go toing physician, proper designation can assist establish early and appropriate intervention to the victim and besides alleviate undue emotional perturbation. Some of the of import differentiating characteristics of toxicant from nonpoisonous serpent are appended below ( 13,18 ) .( a ) Fangs: The most typical characteristic of toxicant serpents is the Fangs.
These are modified dentitions in the upper jaw, by and large two in figure, one on either side. They communicate with salivary secretory organs and are hollow or grooved. In Elapidae and sea serpents they are located in forepart, are short and immobile while they are big, curved and have broad scope of motion in vipers.( B ) Scales on Belly: In toxicant serpents the belly graduated tables are big and extend all across the belly. In nonpoisonous serpents belly graduated tables are little and by and large do n’t widen across the belly.
( degree Celsius ) Head: Vipers have heavier triangular caput with little graduated tables all over. In instance of cavity vipers a cavity is located between the anterior naris and the oculus. Cobra and Krait have big caput graduated tables. In cobra upper 3rd labial is largest and touches the oculus and rhinal shield. In Kraits upper 3rd labial does non touch the oculus and nose, but the 4th lower labial graduated table on the under surface of oral cavity is the largest. All the toxicant sea serpents have big graduated tables on the caput and valved anterior nariss.( vitamin D ) Student: Poisonous serpent have by and large egg-shaped or perpendicular slit.
However students are round in Elapidae ( cobra ) and most nonpoisonous serpents.( vitamin E ) Body design: Krait has cardinal row of big graduated tables on dorsal side, which are about hexangular. It has paired white or black chevrons across the organic structure in the banded Krait. Some cobras have spectacle-like grade on their goon.( degree Fahrenheit ) Fang Markss: In nonpoisonous serpents since all dentitions are at same degree so bite is stretched and bite Markss are along a curving line i.e. row of bites, as in human bite.
Bite site can be easy made out. In toxicant serpents since toxicant dentitions are by and large two ( fang Markss ) and other dentitions areat lower degree, so merely two,1-2 centimeter spaced puncture Markss are seen. A distance of less than 10 mm signifies a little serpent while a distance of over 15 millimeter is implicative of a big serpent. Sometimes one requires manus lens to place these Markss particularly in instances of cobra or Krait bite. It is notable that the size of the venom Fangs has no relation to the virulency of the venom. The comparatively guiltless Indo-MalayLachesisA have tremendous Fangs, whilst the smallest Fangs arefound in theA HydrophidsA which possess really powerful venom.( g ) Sound: Most deadly serpents produce characteristic sounds, which may besides assist in acknowledgment of serpent. Russell ‘s viper produces “ Hissing ” , saw scaled viper “ Rasping ” and King Cobra “ Growling ” sounds.
Easy designation of different serpents is as follows:Cobra: Hood while alive, big graduated tables on caput. Pupil is round and 3rd upper labial touches the oculus and anterior naris. Large belly scales extend acrossthe breadth.Krait: The 4th lower labial graduated table on the under surface of the oral cavity isthe largest.
Hexagonal big graduated tables in the cardinal row on dorsal side. Body may be banded. Belly scales extend across the breadth.Viper: Triangular heavy caput with little graduated tables all over. Large belly scales widen across the breadth.Snake VenomSnake venoms are the most complex of all natural venoms and toxicants. The venom of any species might incorporate more than 100 different toxic and non-toxic proteins and peptides, and besides non-protein toxins, saccharides, lipoids, aminoalkanes, and other little molecules.
The toxins of most importance in human embittering include those that affect the nervous, cardiovascular, and haemostatic systems, and do tissue mortification ( 21 ) .Snake venom is chiefly meant to paralyze the quarry, adult male is merely inadvertent victim to whom snake work stoppages if threatened. Proteins constitute 90-95 % of venom ‘s dry weight and they are responsible for about all of its biological effects. Venom is made up of toxins, atoxic proteins ( which besides have pharmacological belongingss ) , and many enzymes particularly hydrolytic ones.A Enzymes ( molecular weightA 13-150 KDa ) make-up 80-90 % of viperid and 25-70 % of elapid venoms: digestive hydrolases, L-amino acid oxidase, phospholipases, thrombin-likepro-coagulant, andkallikrein-like serine proteasesandA metalloproteinasesA ( hemorrhagins ) , which damage vascular endothelium. PolypeptideA toxins ( mol weight 5-10 KDa ) includeA cytotoxins, A cardiotoxins, and postsynaptic neurolysins ( suchasA I±-bungarotoxinA andA I±-Cobratoxin ) . Compounds with low molecular weight ( up to 1.5 KDa ) include metals, peptides, lipoids, nucleosides, saccharides, aminoalkanes, and oligopeptides, which inhibit angiotensin change overing enzyme ( ACE ) and potentiate bradykinin ( BPP ) .
A PhosphodiesterasesA interfere with the quarry ‘s cardiac system, chiefly to take down theA blood pressure.A Phospholipase A2A causesA hemolysisA by lysing theA phospholipidA cell membranesA ofA red blood cells.A Amino acidA oxidasesandA proteasesA are used for digestion. Amino acerb oxidase besides triggers some other enzymes and is responsible for the xanthous coloring material of the venom of some species.A HyaluronidaseA increases tissue permeableness to speed up soaking up of other enzymes into tissues. Some snake venoms carry fasciculins, like theA mambasA ( Dendroaspis ) , which inhibitA cholinesteraseA to do the quarry lose musculus control ( 22,23 ) .The most deadly venoms are those of elapids and sea serpents.
These toxins are quickly absorbed into the blood watercourse thereby doing rapid systemic effects. Large molecular weight viper toxins are absorbed easy through lymphatics thereby remaining longer at local site, therefore more local effects. Pathophysiology of ophitoxemia is fundamentally dependent on break of normal cellular maps. Some enzymes like spreading factor disseminate venom by interrupting down tissue barriers. Ophitoxemia can take to increase in vascular permeableness thereby doing loss of blood and plasma volume in extravascular infinite.
Collection of this fluid is responsible for hydrops and unstable loss, if important it can take to floor. Venom besides has cytolytic consequence taking to mortification and secondary infection. Neurotoxic consequence may take to paralysis, cardiotoxic consequence can do cardiac apprehension and likewise myotoxic or nephrotoxic consequence can take to rhabdomyolysis and nephritic failure.
Ophitoxaemia besides can take to curdling perturbations.Among the assorted species, the deadly dosage of venom, for cobra is 120 milligram, Krait 60 milligram and for Russell ‘s viper and proverb scaled viper is 150 milligram severally. But clinical characteristics and results are non predictable as every bite does non do complete envenomation.Components of Snake Venom ( 22 ) .
I±-neurotoxinsI±-Bungarotoxin, I±-toxin, erabutoxin, cobratoxinI?-neurotoxinsNotexin, ammodytoxin, I?-Bungarotoxin, crotoxin, taipoxinI?-ToxinsI?-ToxinDendrotoxinsDendrotoxin, toxins I and KCardiotoxinsy-Toxin, cardiotoxin, cytotoxinMyotoxinsMyotoxin-a, crotamineSarafotoxinsSarafotoxins a, B, and cHemorrhaginsPhospholipase A2, mucrotoxin A, hemorrhagic toxins a, B, degree Celsius..
. , HT1, HT2Enzymes ( 22 )
Oxydoreductasesdehydrogenase lactateElapidaeL-amino-acid oxidaseAll speciesCatalaseAll speciesTransferasesAlanine amino transferaseHydrolasesPhospholipase A2All speciesLysophospholipaseElapidae, ViperidaeAcetylcholinesteraseElapidaeAlkaline phosphataseBothropsatroxAcid phosphataseDeinagkistrodonacutus5′-NucleotidaseAll speciesPhosphodiesteraseAll speciesDeoxyribonucleaseAll speciesRibonuclease 1All speciesAdenosine triphosphataseAll speciesAmylaseAll speciesHyaluronidaseAll speciesNAD-NucleotidaseAll speciesKininogenaseViperidaeFactor-X activatorViperidae, CrotalinaeHeparinaseCrotalinaeI±-FibrinogenaseViperidae, CrotalinaeI?-FibrinogenaseViperidae, CrotalinaeI±-I?-FibrinogenaseBitisgabonicaFibrinolytic enzymeCrotalinaeProthrombin activatorCrotalinaeCollagenaseViperidaeElastaseViperidaeLyasesGlucosamine ammonium lyasePathological effects of venom may non be noticed until about six hours ( changing between 1.5-72 hours ) , and it may stay functionally active doing persistent coagulopathy even after three hebdomads of bite. Hence continuance of antigenemia is an of import determiner for the extent of pathological consequence. It has been unambiguously proved by analyzing the venom degrees by enzyme linked immunosorbent check ( ELISA ) , that effects due to envenomation depend on venom hours ( i.e.
Blood venom degree ten clip elapsed between bite and establishment of intervention ) instead than blood degrees entirely. Hence with the same degree of venom, characteristics due to envenomation may go increasingly terrible with transition of clip ( 14,20 ) .There are four distinguishable types of venom effects.
ProteolyticA venomA dismantles the molecular construction of the country environing and including the bite.HemotoxicA venomsA act on the bosom and cardiovascular system.NeurotoxicA venomA Acts of the Apostless on the nervous system and encephalon.CytotoxicA venomA has a localized action at the site of the bite.
Pathophysiology of assorted biological effects of serpent envenomationThe undermentioned few paragraphs shall depict the biological effects of venom.( a ) Local Swelling: Most viper bites cause local puffiness at the site of bite, which starts within proceedingss of bite and monolithic puffiness of the limb may develop within 48-72 hours. This is normally the consequence of hemorragins in the venom. This opens the endothelial pores ensuing in escape of plasma or whole blood. At times leakage may be so much that patient develops hypovolaemic daze. This swelling is non due to any venous occlusion or infection.
If the exudate is of whole blood, so later stain of the limb may develop. In contrast to Echis, in European adder V berus bites, self-generated hemorrhage is rare but stain is common. Sometimes local puffiness is delayed and compartment syndrome may ensue ( 10,13,17 ) .( B ) Local Necrosis: In viper bites local mortification appears tardily if at all and if it occurs, it is due to ischemia, miming dry sphacelus. On the other manus in Cobra bite local mortification appears early.
Local puffiness may develop after 2-3 hours but necrosis develops quickly after that. It is due to cytolytic factors present in the venom and is a wet sphacelus. As this dead tissue provides ideal puting for anaerobes, therefore the putrid odor. An early deletion is warranted ( 13 ) .( degree Celsius ) Non-specific early symptoms: With bites of some vipers e.g. V berus, V xanthina, Australian elapids, some rattle serpents etca few symptoms are common. Vomiting, concern, abdominal hurting, explosive diarrhoea and prostration can happen.
These characteristics resolve in 30-60 proceedingss, proposing activation of kinin system followed by suppression of bradykinin ( 13,17 ) .( vitamin D ) Daze: It can develop due to extended volume leak from vass in instances of viper bite. It can ensue even before a limb gets swollen. Pneumonic intra vascular curdling, pneumonic hydrops and cardiac effects can be conducive factors for daze.( vitamin E ) Spontaneous bleeding: Bleedings can develop in patients with viper bites even yearss after the bite.
These at times may be life endangering particularly if they occur in encephalon. Local blisters at bite site appear to be terminal of venom, which do n’t acquire targeted by anti serpent venom. Therefore one must maintain in head the delayed soaking up from bite site in patients who present with late hemorrhage manifestations despite holding been given anti-snake venom a few yearss back.( degree Fahrenheit ) Consequence on Circulation: Some viper venoms contain procoagulant activity which activates factor II to thrombin ; which in bend converts factor I to fibrin while in others procoagulant venom may straight impact factor I. This fibrin formed is susceptible to lysis unlike natural fibrin therefore ensuing in ill clottable or non-clottable blood because of absent or really low degrees of factor I. It should be remembered that shed blooding manifestations during envenomation are non by and large due to curdling perturbations but instead due to haemorrhagin. Platelet count may besides be low though normally it is normal. Low thrombocyte count is due to ingestion of thrombocytes in the fix of endothelial harm.
Polymorphonuclearleucocytosis is common in all signifiers of envenomation particularly terrible envenomation. Both viper and elapidae bite may hold haemolytic activity in vitro but unnatural haemolysis is seldom of clinical importance except likely in nephritic failure ( 13,17 ) .( g ) Nephritic Failure: Nephritic failure is a common manifestation of viperine envenomation particularly where intervention has been delayed. On nephritic biopsy ague cannular mortification is the commonest implicit in lesion in 50-70 % of instances and acute cortical mortification ( patchy / diffuse ) has been found in 20-25 % of instances. Hypovolemia and daze are the usual implicit in mechanism. Other conducive factors are hemo/ myoglobinuria, haemolysis, associated sepsis and disseminated intravascular curdling ( 24 ) . Glomerular lesions have besides been described in snake bite instances.
Merchant et Al ( 25 ) have reported mesangial proliferation, splitting of cellar membrane, swelling of endothelial cells and ballooning of glomerular capillaries, but the significance of these lesions in doing nephritic failure is non clear and is problematic. Seedat et Al ( 26 ) reported two instances due to whiff adder who developed oliguric nephritic failure and biopsy showed crescenticglomerulunephritis. Writers suspected hypersensitivity of venom as the cause. Occasional casesof terrible glomerulonephritis related nephritic failure have been reported in the literature. Experimental surveies carried out on the consequence of Habu snake venom ( found in Japan ) has given some penetration into apprehension of the glomerular lesion. This venom contains hemorrhagin, like the venom of Echiscarinatus. Within 24 hours of injection of this venom devastation of mesangium occurs ensuing in ballooning of capillaries which become packed with ruddy cells and fibrin giving an visual aspect of blood cysts. This is followed by proliferation of mesangial cells giving visual aspect of segmental proliferative glomerulonephritis.
Rarely crescents are observed. These surveies provide grounds that these glomerular alterations are due to vasculotoxic effects of hemorrhagin. However about cannular mortification or cortical mortification, the commonest lesion encountered in snake envenomation, there is no consensus that venom has any direct toxic consequence in bring forthing these lesions ( 27,28 ) .( H ) Neurotoxic effects: Elapidae venom and sea snake venom cause neurotoxic effects due to neuromuscular encirclement. Normally affected musculuss in Elapidae bite are those of oculus, lingua, pharynx and thorax ( taking to respiratory palsy in terrible envenomation ) . Neurotoxins are little molecular weight positively charged molecules with less antigenecity. Neuro- muscular encirclement is produced by one of the undermentioned mechanisms. ( a ) Post synaptic block ( Cobra ) cobratoxin and alpha-bungarotoxins act similar to d-tubocurarine on the station synaptic membrane.
There is no lessening in acetyl choline. Response to neostigmine is satisfactory. ( B ) Pre-synaptic encirclement ( Krait ) beta- bungarotoxin Acts of the Apostless like botulism toxin pre synaptically to barricade the neuro-muscular junction.
Post junctional membrane remains sensitive to acetyl choline. The clip required for neuromuscular block varies with impulse traffic, hence intense physical activity shortens the interval between envenomation and neuromuscular block. Response to neostigmine is less satisfactory. It is of import to observe that these neurolysins do n’t traverse the blood encephalon barrier and hence do non do change in consciousness. Hence in instance of altered sensorium an alternate cause should be found ( 23,29 ) .( I ) Cardiotoxic Effects: Cardiotoxin ( Cobra ) acts on cell membrane of skeletal, smooth and cardiac musculus to bring forth palsy and cardiac cardiac arrest. Cobramine B and cytoxin cause irreversible depolarisation of cell membrane and systolic cardiac apprehension.
Hyperkalemia following monolithic haemolysis or rhabdomyolysis besides depresses cardiac map.( J ) Myotoxic Effects: Although sea snake venom appears to be neurotoxic in carnal experiments, the effects in adult male are chiefly myotoxic. There is diffuse consequence on all musculuss though local effects at the site of bite are minimum. In worlds bitten by sea serpents the findings are typical of generalised myopathic lesions in skeletal musculus. Damage to muscles- rhabdomyolysis and hyperkalemia ensuing from it may be life endangering. Snake envenomation has so diverse effects that every system of the organic structure is affected straight or indirectly ( 20,29 ) .
DecisionSince ancient times serpents have been worshiped, feared or loathed in India. It is a common and often lay waste toing environmental and occupational disease, particularly in rural countries of our country.India has the highest figure of decease to snake bite in the universe. One of the major spreads in the conflict against snakebite in India is the deficiency of qualitative work. Most Herpetology text books give snake designation informations that is overtly complex and of small usage to physicians. Snakes are misidentified by physicians in most instances where serpent is brought to the hospital.
Without the serpent, designation based on symptomatology is clearly fraught with jobs. The physicians should be cognizant of find of a new toxicant serpent, the Hump-nosed Pitviper ( Hypnale Hypnale ) which has no available antivenom at present. Community instruction, appropriate preparation of medical staff and better distribution of anti venom, particularly in the provinces with the high prevalence, could cut down snakebite deceases in India.