Arterial.12.Gangrene Flashcards
Gangrene
- DEFINITION
- CARDINAL SIGNS
- ETIOLOGY
- CLINICAL TYPES
DEFINITION of Gangrene
macroscopic death of tissues that is
generally caused by loss of blood supply and is usually associated with bacterial invasion and putrefaction
CARDINAL SIGNS of Gangrene
- mnemonic
- List
- Threatened Gangrene
mnemonic for CARDINAL SIGNS of Gangrene
Press and See How Color Fades
List of CARDINAL SIGNS of Gangrene
The five cardinal signs of local death are:
- Loss of pulsation and sluggish capillary circulation.
- Loss of sensation.
- Loss of heat “Cold extremity unless infected”.
- Fixed skin color change
- Loss of function “paralyzed extremity”.
Fixed skin color change in Gangrene in List of CARDINAL SIGNS of Gangrene
- Change of skin color into blue and later black :
* The color does not change by local pressure.
Threatened Gangrene in CARDINAL SIGNS of Gangrene
- Patients suffering from threatened gangrene have all CARDINAL SIGNS of Gangrene
- but tissues are still viable and local Pressure Causes some modification of Color which returns when the Pressure is released.
ETIOLOGY of Gangrene
- Ischemic
- Neuropathic :
- Traumatic
- Physico-chemical
- Infective:
- Venous gangrene.
Ischemic ETIOLOGY of Gangrene
- Thrombosis: On top of atherosclerosis (senile gangrene).
- Embolism
- Vasospastic disease: Raynaud’s disease
Senile gangrene in Ischemic ETIOLOGY of Gangrene
ischemic gangrene caused by Thrombosis On top of atherosclerosis
Neuropathic ETIOLOGY of Gangrene
- Diabetes Mellitus
* leprosy
Traumatic ETIOLOGY of Gangrene
Direct trauma: Due to crushing or pressure (bed sores).
- Indirect trauma: Due to injury of the main vessels.
Physico-chemical ETIOLOGY of Gangrene
- Burns
- Frost-bite
- Trench foot
Frost-bite in Physico-chemical ETIOLOGY of Gangrene
Damage to tissues as the result of exposure to low environmental temperatures, also called congelation
Trench foot in Physico-chemical ETIOLOGY of Gangrene
a type of immersion foot resembling frostbite caused by prolonged action of cold water on the skin combined with circulatory disturbance due to cold and inaction
Infective ETIOLOGY of Gangrene
- Specific infection:
2. Non-specific infections
Specific infection in Infective ETIOLOGY of Gangrene
Clostridial gas gangrene
Nonspecific infections in Infective ETIOLOGY of Gangrene
As carbuncle, anaerobic cellulitis
CLINICAL TYPES of Gangrene
l - Dry Gangrene
II- Moist aseptic gangrene
II- Moist septic gangrene
IV- Special Types of gangrene :
A. Decubitus ulcer : Look plastic.
B. Idiopathic gangrene of the scrotum
Dry gangrene in CLINICAL TYPES of Gangrene
- Etiology and pathogenesis
- Clinical picture
- Management
Etiology and pathogenesis of Dry gangrene in CLINICAL TYPES of Gangrene
Chronic ischemia as gradual slowing of the blood flow permits free evaporation from the affected surface & for venous & lymphatic drainage.
Clinical picture of Dry gangrene in CLINICAL TYPES of Gangrene
- Hard.
- Dry.
- Wrinkled and shrunken
- Line of demarcation
- Line of separation
Line of demarcation in Clinical picture of Dry gangrene in CLINICAL TYPES of Gangrene
a. A zone of demarcation between the truly viable and the dead or dying tissue, indicated on the surface by a band of hyperemia and by hyperesthesia.
b- In the absence of infection, the dead part is cast off by a process of ulceration at the expense of the dead tissue which is invaded by granulation tissue extending from the living tissues.
Line of separation of Dry gangrene in CLINICAL TYPES of Gangrene
a. The granulation tissue advances until its blood supply cannot cope with further growth.
b. The line of separation thus lies distal to the line of demarcation and the resulting stump is conical.
The reason why the resulting stump of dry gangrene is conical in Line of separation of Dry gangrene in CLINICAL TYPES of Gangrene
because the blood supply is more adequate in muscles and bone, these separate more distally than the skin
Management of Dry gangrene in CLINICAL TYPES of Gangrene
- Amputation is NOT urgent.
* The patient should be fully investigated for chronic ischaemia
Moist aseptic gangrene in CLINICAL TYPES of Gangrene
- Etiology
* Clinical picture
Etiology of Moist aseptic gangrene in CLINICAL TYPES of Gangrene
a. Acute ischaemia.
b. chronic ischaemia with pre-existing edema (e.g cardiac)
Clinical picture of Moist aseptic gangrene in CLINICAL TYPES of Gangrene
- Dead part is of usual size and consistency
- with dark color
- Skin blebs.
- Offensive odour
Moist septic gangrene in CLINICAL TYPES of Gangrene
- Etiology
- Clinical picture
- Treatment
Etiology in Moist septic gangrene in CLINICAL TYPES of Gangrene
- 1ry infective gangrene
2. 2ry infective gangrene
1ry infective gangrene in Etiology in Moist septic gangrene in CLINICAL TYPES of Gangrene
infection of tissues with virulent organisms
2ry infective gangrene in Etiology in Moist septic gangrene in CLINICAL TYPES of Gangrene
Infection of sterile gangrene
Clinical picture of Moist septic gangrene in CLINICAL TYPES of Gangrene
- Part examination
2. Skin examination
Part examination in Clinical picture of Moist septic gangrene in CLINICAL TYPES of Gangrene
- The part becomes swollen, edematous, and markedly inflamed.
- The part emits a very offensive odour, and may crepitate
- There is a marked inflammatory reaction in the living tissues above it.
- Severe constitutional signs are present and death may supervene rapidly from septicemia.
the reason why the part becomes swollen, edematous, and markedly inflamed in Part examination in Clinical picture of Moist septic gangrene in CLINICAL TYPES of Gangrene
Because of the infection
the reason why The part emits a very offensive odour in Part examination in Clinical picture of Moist septic gangrene in CLINICAL TYPES of Gangrene
due to gas formation from rapid decomposition.
Skin examination in Clinical picture of Moist septic gangrene in CLINICAL TYPES of Gangrene
- The skin appears moist and blotchy
* bullae filled with serum are found
Treatment of Moist septic gangrene in CLINICAL TYPES of Gangrene
- Amputation is urgent.
- Pathogenesis of separation In the presence of infection
- Extent of inflammation
Pathogenesis of separation In the presence of infection in Treatment of Moist septic gangrene in CLINICAL TYPES of Gangrene
separation is accomplished by a process of suppuration at the expense of the living tissues.
Extent of inflammation in Treatment of Moist septic gangrene in CLINICAL TYPES of Gangrene
The inflammation is not limited to the line of demarcation but spreads upwards along the lymphatic, veins or in the fascial & muscular planes
Special Types of gangrene in CLINICAL TYPES of Gangrene
A. Decubitus ulcer “Bed sores” : Look plastic.
B. Idiopathic gangrene of the scrotum
Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
- Alternative name
- Definition
- Etiology
- Treatment
- Prognosis
Alternative name for Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
Fournier’s gangrene
Definition of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
Sudden onset of scrotal inflammation & gangrene of the skin of the scrotum
Etiology of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
- Predisposing factor
* Precipitating factor (Causative organism )
Predisposing factor in Etiology of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
May follow minor injuries to the perineum
Precipitating factor (Causative organism ) in Etiology of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
synergistic infection mainly by
- hemolytic streptococci
- staph
- E.coli.
Treatment of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
Massive debridement to be followed by skin graft to cover the testis.
Prognosis of Idiopathic gangrene of the scrotum in Special Types of gangrene in CLINICAL TYPES of Gangrene
many patients die in spite of active treatment.
