Envenomation stings

ENVENOMATION
Definition:
The injection of a venom etc by means of a sting,etc.
STINGS:
Def : A pointed portion of a insect used for attack.
Order of insects belongs to stings are:
a)Hymenoptera- bees, wasps, hornets, fire ants.
b)Scorpionida- scorpions.

Vespids
↓
Apids
↓
Formicids
↓
Wasps Honey Bees Fire ants
Hornets,Yellow jackets.
-
Jumper ants
1) ORDER HYMENOPTERA:
Temperate regions.
It consists of - Are as follows:

 Body of Honey bee - bright yellow with black triangular marking on
abdomen.
 They attract to Sweet & Meat.(10-15mm length of body).
 Queen wasps- grow up to 20mm.
 Inject venom- barbed- by bees -50mcg venom injected.
-smooth- by wasps.
 Ants- Use jaws & then sting/spray- local irritating venom.
 Some contain abdomen stingers-multiple stings.

VENOM:
 It contains - a) Biogenic amines - Histamins,ACH.
- b) Enzymes - Phospholipase A, Hyalouronidase.
- c) Toxic peptides - Kinins,Mast cell degranulation-
peptides,Apamin,etc.
High risk factors Lab diagnosis
Age 60yrs/ more. Intradermal test
Prolonged attack time. Positive venom skin test
High no. of stings Radio allegro absorbent test
Medical history include c.vascular
problems.
CLINICAL FEATURES:

Clinical features Treatment
Local reaction: Single sting-not allergic to
venom-mild effects,local pain.
Local reaction:at vital
location:mouth-
aedama,airway obstruction.
By wasps-severe cutaneous
infection& cellulitis.
1. Remove stings use fingernails/blade
but avoid foreceps.
2. Adrenaline(1:1000)near sting site.
3. Papain-Relief psin.
4. Local application – 20%Aluminium
sulfate.
5. Antihistamins-
Diphenydramine(500mg).
6. Chlorphenaramine(4mg)
7. LOCAL ANTISEPTIC CREAM
8. Antibiotics for oinfections.
Allergic rxn –
a)Anaphylaxis:
4% human population-
hypesensitive to venom.
Signs- tingling
sensation,flushing,vomiting.
 0.1% adrenaline
 Antihistamins
 Corticosteroids
 Cardiac monitoring.
b) Delayed rxn:
Urticarial,skin rash,pedal
edema.
Sometimes fever,rash,malasia.
1. Antihistamins,
2. Analgesics,
3. Haemodialysis- for renal failure.

Toxic rxn: Multiple stings -
vasodilation,
hypotension,fatigue,
dirrhoea,headache,
seizeures.
Delayed toxic rxn:
Haemodialysis,coagulopathy.
 Parenteral
antihistamins.
 Large dose
corticosteroids.
 Bronchodilators.Haemo
dialysis.

PREVENTIVE MEASURES:
 Individual recovered from anaphylaxis from insect trained to self administer
adrenaline.
 Wear tag for unconscious persons - after sting bite to discover them.
 Destroy Hymnoptera nests I areas near to you.
 Wear light coloured ,long sleeved,tight clothes.
 Avoid bright /attractive colours,floral patterns.
 Attractive scents,perfumes,soaps,shampoo- avoid in high risk area.
 Take βblockers/Non steroidal analgesics.
 Avoid ACE inhibiotors/calcium channel Antagonist.
 Immune therpy for - benefit from allergy.

2) ORDER SCORPIONIDA:
 It consists of 8legs cephalothorax,6 segmented tail,telson,sting,2 claws to
catch prey.
 650 different species- into 6 families.
 Most species- nocturnal& seek area that rae cool& moist.
 Straw yellow/ light browm/black colour.
 India – red scorpion(Mesobuthus tamulus)-03 inches in length.
 Larger scorpions(Palamnaeus species)
 7inches in length.
 General rule- scorpions with thick & powerful claws- less toxic.
 Slender claws- more toxic.
 Scorpion sting- they do not bite.

Venom :
1. Most potent.
2. It contain phospholipase,Ach,Hyaluronidase,serotonin,Neurotoxins.
3. It causes - Gastro intestinal & Pulmonary haemorrhages.
Mode of Action:
 Venom affects Na+ channels with pprolongation of Action
Potentials.
 Depolarisation of Nerves of both Adenergic & Parasympathetic
system.

LOCAL SYSTEMIC
Rapidly developing local pain Autonomic stimulation
swelling mydriasis
redness Profuse sweating
lymphadenopathy urticaria
HTN
convulsions
Priapism,nausea.
CLINICAL FEATURES:

Lab tests:
1. ECG – Elevated T waves.
Elevated ST segment.
Treatment:
Child over age of 5years – local application of ice for pain relief.

TREATMENT:
1)During transport to hospital:
 Immobilize,
 No transport,
 Local ice apply,
 -ve pressure suction device.
 No incision/suction.
2)On Arrival at Hospital:
1. Rep. failure- Mech. Ventilation.
2. Pain- PCM/Morphine tabs.
3. Allergy- Antihistamins.
4. HTN- Nifidepine.
5. Correct fluid & acid base imbalance.
6. Hypotension- Dopamine(2-5mcg/kg/min)
7. Convulsions- Diaxepam(5-10mg)
8. Vomiting- metoclopramide.
9. Antivenom therapy- scorpion antivenom- 1vial in 10 ml injection.

1. Modern Medical Toxicology –vv. Pillay ,4th Edition.Pg:157.
2. Hodgson, Ernest (2010). A Textbook of Modern Toxicology. John
Wiley and Sons.
3. Berg, N; De Wever, B; Fuchs, H. W.; Gaca, M; Krul, C; Roggen, E. L.
(2011).
4. "Toxicology in the 21st century--working our way towards a
visionary reality". Toxicology in Vitro 25 (4): 874–81

Envenomation stings

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Envenomation stings

Similar to Envenomation stings (20)

More from SUDEEP

More from SUDEEP (6)

Recently uploaded

Recently uploaded (20)

Envenomation stings