Corrosives

1. hp
By Dr. Ahmed Wagdy
Corrosives

2. Dr.Ahmed Wagdy
Corrosives
Organic
corrosives
Inorganic
Point of
comparison
Oxalic acid
Phenol
Alkalis
drain cleaner,
soap, swimming
pool
cleaners,
bleachers
Acids
toilet bowl
cleaning, rust
removal
products, metal
& drain cleaning
prod
Uses
used for metal
polish & removing
ink stains
It is a- coal tar
derivative, with
characteristic smell.
***
Disinfectant
-
Mistaken by
children for
sugar or salt
[as it is in
form
of white
].
crystals
:
Accidental
Suicidal:
1-Easily obtained.
2-Cheap.
Painless death
-
3
Homicidal: Never
due to characteristic
.
smell
Accidental;
children
drink
potash [K2 Co3]
which simulate
milk in its
color
Accidental:
occupational &
children.
Homicidal:
throwing
on face
4
SO
2
H
Condition of
poisoning
local and
Remote effects
Local
Stomach: mild
corrosive
[superficial
ulcers].
Skin: Eschars
Remote
Oxalic acid
combines with
ionized blood
calcium
forming
insoluble
calcium oxalate
leads to renal
stone
Metabolic
acidosis
Hypocalcemia
arrythmia and
y
tetan
local and Remote
effects
and
Skin
Local
stomach mild
corrosive
coagulative necrosis
[thickening of gastric
mucosa]
Remote
CNS: stimulate and
then depress the CNS
CVS: direct myocardial
depressant effect
RESPIRATION:
Respiratory alkalosis
Metabolic : Metabolic
acidosis due to renal
damage.
Methemoglobinemia
Acute glomerulonephritis
local action
only”
Destruction to
the tissues by
liquefactive
necrosis
causes
stricture of
****
s +
esophagu
skin Eschars
If skin
exposed:-
- White eschars
***
By
on
saponificati
local action
only”
coagulative
Eschars
necrosis
formation limits
penetration
Mainly
cause
perforation of
+
stomach
skin
eschars]
Black eschars
(H2 SO4)
- Red eschars
(Hcl).
- Yellow
eschars
(HNO3)
Mechanism
of action

3. Dr.Ahmed Wagdy
Local effect
-Pain and
vomiting of
white crystals
-Dehydration
Remote
Hypocalcemia
Twitches of the
face muscles
and extremities
with
carpopedal
****
spasm
Renal failure
ca
Oliguria with
oxalate crystals
CVS
Arrhythmias or
cardiac a
systole
Stomach:
Pain + Vomiting with
characteristic smell
[temporary due to
local anesthetic
effect)
:
Skin
- Whitish eschars
around the mouth or
skin turn brown
constricted
::
CNS
*****
pupil
CVS:: Cardiovascular
collapse hypotension
Kidney:" urine turns
green (due to
hydroquinone)
Alkali Severe pain from mouth
to stomach
Dysarthria and Dysphagia
black in color
-
Vomiting:
[shreds of stomach mucosa +
Constipation
]
acidic haemitin
***
White and
-
Vomiting:
Acid
soapy
[shreds of stomach mucosa +
Alkaline haematin] =
Diarrhea (white and soapy)
Clinical
picture
1)Renal
function tests.
2) Urine
analysis [white
Ca oxalate
crystals].
3) Ca level in
blood.
4) ECG
monitoring.
5) Arterial
.
blood gases
1)Renal function
tests.
2) Urine analysis
[green urine due to
the metabolite
***
]
hydroquinone
..
3) Arterial blood
gases.
4) Methemoglobin
level
1) Renal function tests.
2) Arterial blood gases
3) Abdominal x-ray
(perforation)
4) Fiberoptic endoscopy
Investigations
15
Within
due to
minutes
respiratory
failure
[peripheral
asphyxia
few
Within
from
hours
obstructive
renal failure
Cardiac arrest
***
4 hrs
Within
Respiratory failure
(central asphyxia)
4 days
Within
Renal failure
Shock [Neurogenic] ***
Immediately
Asphyxia “Within few hrs.
Dehydration [oligemic shock]
within 12H
Perforation of stomach within
days”
Cachexia [stricture of
esophagus] within weeks
Causes of
death
Perforation is more in acids
Cachexia is more in alkalis

4. Dr.Ahmed Wagdy
1-Supportive
measures
2-Gastric
Lavage + Local
antidote [Milk]
or CaOH2 to
precipitate
oxalic acid as
ca oxalate and
decrease its
.
absorption
3-Dialysis
Ca gluconate
***10% IV
slowly or orally
to treat
.
hypocalcemia
4-
symptomatic:
Convulsions:
-Diazepam
--IV fluids to
prevent
calcium oxalate
1- Supportive
measures
not
is
Emesis
-
2
recommended
Gastric lavage is
-
:
due to
indicated
- Vomiting is
[local
temporary
**
n]
anesthetic actio
No fear of
perforation
Milk
Local antidote
-
3
and egg white
Olive oil and /or
glycerin
4-Dialysis
5-Symptomatic
ethanol 10 **% as a
local antidote as it
dissolves
phenol then rapidly
removed by gastric lavage
Supportive
-
1
GIT decontamination :
-
2
due to fear of
contraindicated
perforation
gastric lavage
No
,
emesis
No
neutralization: potential to form
gas & exothermic reaction
Water also is Contraindicated in
alkaline potash due to production
of heat *****
3- Local Antidotes:
demulcent
Milk and egg white [
-
effect].
- H2 blockers Ranitidine to
decrease acid secretion
TTT