Naja atra bite/envenomation study

[Qball]

Found this now on the web while doing some reading, thought you guys might find it as interesting as I did. Don't think the link has been posted before, but I may be incorrect.

http://www.hkmj.org/article_pdfs/hkm1002p36.pdf

[yoson10]

Good stuff Qball and these type of studies while clearly not perfect will give you a 10x better understanding on venom toxicity and it's general effects on humans then any "most venomous list."

Of course the fact that venom varies regionally within the same snake complicates things alot...A chinese cobra from another area may cause different symptoms and more/less severe neurotoxicity etc.

[Qball]

I was quite amazed at the amount of necrosis... It was interesting to see the type of surgical interventions needed and the lenght of hospital stay relating to each case.

[WW]

Thanks for posting that link - I had missed that paper.

Necrosis of that type is common with many Asian cobras, although most species show a much higher incidence of clinically significant neurotoxicity. Mind you, African spitters can do as bad and worse.

[yoson10]

Some Asian Cobras from certain areas can be horribly necrotic....worse in some cases than the vipers they share a range with...And I'm not talking about spitting cobras...I'm talking about regular cobras...


For Russell’s viper: (D. russelii) bites (319 cases), local swelling and regional lymphadenopathy developed in 307 (96%) patients. Incoagulable blood (20-minute whole blood clotting test) occurred in 244 (76%). There was persistent bleeding from bite (46%) or venipuncture (38%) sites. Spontaneous bleeding manifested as hematuria (47%), gum bleeding (34%), hematemesis (34%), vaginal or rectal bleeding (2%), and ecchymosis and bruising (11%). Acute renal failure that required peritoneal or hemodialysis developed in 60 (19%) patients. Fifty-seven percent showed neurotoxic signs, 24% showed generalized myalgia, and 2% showed respiratory failure that required mechanical ventilation.


For hump-nosed pit viper: (H. hypnale) (302 cases), 276 (91%) patients had local swelling and 186 (62%) had blistering. Incoagulable blood and spontaneous bleeding occurred in 117 patients (39%). Acute renal failure that required dialysis developed in 30 (10%) patients. None had neurotoxic signs.



For saw-scaled viper: (E. carinatus) (1 case), local bleeding, swelling, incoagulable blood, and spontaneous bleeding developed in one patient. He did not develop acute renal failure or neurotoxicity.



For cobra: (N. naja) (45 cases), these patients often had severe neurotoxic signs and/or local envenoming (swelling, pain, blistering, necrosis). Local swelling developed in 91% of patients, blistering in 84%, and necrosis in 67%. Thirty-four patients (76%) required wound debridement and 16 (36%) needed skin grafting. Eight (18%) required amputation of limbs, fingers, or toes. Thirty-six (80%) developed neurotoxic signs, of which 35 (78%) had ptosis, 29 (64%) had ophthalmoplegia, 6 (13%) had dysphagia, and 9% had respiratory failure that required mechanical ventilation. No patient developed spontaneous bleeding, incoagulable blood, or acute renal failure.



For common krait: (B. caeruleus) (88 cases), symptoms or signs of local envenoming (minimal swelling, pain, paraesthesiae) were recorded in 9% of the patients. Typical neurotoxic signs, such as partial or complete ptosis, external ophthalmoplegia, and difficulty in breathing, which were identical to those observed in cobra bite victims, developed in 84 (95%) patients and respiratory failure that required mechanical ventilation developed in 64%. Abdominal pain and/or vomiting were reported in 80 (91%). No patient had spontaneous bleeding or incoagulable blood.



For sea snake: (Hydrophis spiralis) (1 case), one bite victim had no signs of local envenoming. Multiple fang marks were observed at the site of bite. He had severe myalgia, muscle tenderness, and neurotoxic signs but did not develop respiratory failure or acute renal failure.


For green pit viper: (Trimeresurus trigonocephalus) (6 cases), four patients (67%) had local swelling. One complained of abdominal pain and vomiting. None had signs of systemic envenoming.


http://www.ajtmh.org/content/81/4/725.full


And only snakes that were brought in dead were included in the study so the study is 100 percent accurate

[Qball]

Thanks for sharing!