Gangrene

 Gangrene

Definition

 It is a  condition characterized by  death of tissues due to ischemia and decomposition.

 Aetiology

Mechanism	Causes
Loss of blood supply	.Arterial thrombosis. .Arterial embolism. .Tight plaster of Paris cast. .Raynaud’s disease. .Burger’s disease. .Ergot poisoning. .Thromboangitis obliterans. .Prolonged application of a tourniquet.
Physical or chemical violence	.Carbolic acid burns. .Frost bite. .Severe burns. .Radiation injury.
Infection	Gangrene.

Types

1.Moist gangrene: The dead cells are  moist and get infected readily. The gangrene spreads rapidly. There is no sharp line of demarcation between the dead and adjacent live tissues. Toxins are absorbed by live cells nearby as a result of which the patient looks toxic.

2.Dry gangrene: The dead part is dry. It spreads slowly. The  demarcation between the dead and adjacent normal part is distinct.

3.Gas gangrene.

 

Gas gangrene

 

Gas gangrene is a type of gangrene in which there is production of gas due to decomposition of the dead tissue, caused by anaerobic bacteria called clostridium welchii and clostridium sporogenes. Their products are as shown in the following table:-

 

Organism	Product
Clostridium welchii	Decomposition of glucose to produce carbon dioxide and hydrogen.
Clostridium sporogenes	Break down  of proteins to produce hydrogen disulphide and hydrogen.

 

 

The organisms are anaerobic. The oxygen required for their growth is obtained from the process of decomposition of dead tissues. They cannot survive in the presence of free oxygen. The gas generated spreads through muscles and other tissues. It compresses blood vessels and impairs circulation through them. The toxin produced by the bacteria gets absorbed into circulation, as a result of which the patient looks toxic.

Clinical features

1.Severe pain in the wound.

2.The wound is blackish or greenish in colour.

3.Foul smell of the wound.

4.Gas bubbles may be found escaping through the wound.

5.The skin around the wound may be swollen and with blebs.

6.Crepitation  on palpation of the swollen areas.

7.The general condition of the patient deteriorates rapidly if not treated in time.

 Investigations

1.Radiograph of the affected part: Gas in tissues.

2.Culture of the discharge from the wound: clostridium welchii and clostridium sporogenes.

 

Treatment

1.Debridement and drainage of the wound.

         .Removal of all dead tissue.

         .Cleaning of the wound with hydrogen peroxide followed by normal saline.

         .Exposure of the wound to oxygen.

2.Blood transfusion.

3.Broad spectrum antibiotics.

4.Anti gas gangrene serum.

5.Isolation technique of nursing.

6.Hyperbaric oxygen therapy.

7.Surgical removal of the affected part.

 

Acute gangrene

It is seen in a patient with heart disease. Blood clots are formed in the heart and one of the clots embolizes to periphery. Occlusion of an artery of the lower limb results in gangrene of distal part of the limb.

 

Clinical features

1.Sudden onset of severe pain in the lower limb.

2.The pain is relieved after some time and sensations are lost from the lower limb.

3.The patient is unable to move the lower limb.

4.The limb is cold.

5.The color of the limb is pale at first and then it becomes bluish.

6.Arterial pulsations are not felt in the limb.

Treatment

1.Anticoagulation treatment is started immediately.

2.The Clot occluding the blood vessel is removed using   Fogarty catheter.

3.The arterial pulsation in the limb are checked periodically and postoperatively.

 

Senile Gangrene

          Arteriosclerosis due to aging.

                                 ^

 Reduction in blood supply to the lower limbs.

                                  ^

Initiation of gangrene due to minor trauma locally.

 

Clinical  features

1.The initiating factor may be any of the following:-

                .Minor wound.

                .Injury to the nail.

                 .Slipping.

                 .Corn.

2.The gangrene usually involves a toe.

3.The affected area feel cold.

4.It is bluish at first. Then it becomes black in color.

5.Sensation are lost from affected part.

6.The gangrenous part is dry if there is no injection.

Treatment

1.The part is kept cool by directing the breeze from a fan over it so that its oxygen requirements are reduced.

2.The affected partis kept clean and dry.

3.It is cleaned by application  of spirit periodically.

4.Gentian violet is applied if any part is moist.

5.Interdigital clefts are kept  dry, and  the toes are kept separate from each other as far as possible.

6.Foam or cotton is used to prevent pressure on the heel.

7.Lumbar sympathectomy is done to reduce arterial spasm and improve blood supply to the lower limbs.

8.Amputation of the limb is done at a level below which the blood supply is impaired.

9.Antibiotics are given to prevent infection of the gangrenous part.

 

Nursing care

General nursing care is as for any other patient, with emphasis on the points shown in the following table:-

 

                                                         Nursing Care

 

Nursing care	Effects
Head high position	Improvement in blood supply to the lower limbs.
Bed cradle	Prevention of pressure of the bed clothes on the affected part.
Dry and soft bed	Prevention of trauma or pressure effect on the ischemic limb.
Patience	Prevention or irritability of the patient.
Quino barbitone	Vasodilatation and improvement of blood supply to the lower limbs, and relief from pain.

 

 

Diabetic Gangrene

The factors Contributing to the development of gangrene in a diabetic person are as follows:-

1.Arteriosclerosis.

2.Peripheral neuritis as a complication f diabetes, which reduces the sensations in the lower limb and predisposes to trauma  to the limb, which is not noticed.

3.Elevated blood sugar levels predispose to the development  of infections. That results  in development of a big, moist, gangrenous area from a small, dry gangrenous area.

Treatment

1.Control of diabetes with the following measures:-

           .Insulin.

           .Diabetic diet.

            .Exercises.

2. Careful dressing of the affected part every day.

3. Removal of gangrenous portion as soon as the diabetes is controlled and the patient is fit to undergo surgery.

 

Raynaud’s Disease and Thromboangitis Obliterans.

 

                       Comparision of Raynaud’s Disease and Thromboangitis Obliterans

 

Variable	Raynaud’s disease	Thromboangitis obliterans
Age	Young.	Middle.
Sex	Male<female.	Male>female.
Causes	Hypersensitivity to cold.	Use  of tobacco in any form, use of vibrating  tools.
Site of involvement	Upper limb.	Lower limb.
Treatment	.Avoid exposure to cold.	.Stop use of tobacco in any form.
	.Vasodilators.
	.Amputation is not often required.	Amputation.
	.Cervical sympathectomy.	Lumbar sympathectomy.