Rabu, 26 Oktober 2011

Diagnosis and Management of Hemorrhage in Oral Surgery

What is meant by Hemorrhage ?
Prolonged or uncontrolled bleeding is often referred to as hemorrhage.
The amount of blood lost as a result of hemorrhage can range from minimal to significant quantities.

Hemorrhage in Surgery
Hemorrhage  can occur to a greater or lesser degree during all surgical procedures and it’s management depends upon whether the patient is hematologically normal or suffers from some disturbance in the normal clotting mechanism.

The overwhelming majority of patients who undergo oral surgical procedures are those who have normal haemostatic mechanism.
Therefore, significant or major hemorrhages are not that common in oral surgery except in patients who have a bleeding / clotting disorder or those who are on anticoagulants.

However, uncontrolled and persistent bleeding can occur in some healthy patients after dental extraction.
Therefore, it is still important to achieve proper hemostasis in all patients during oral surgical procedures, so as to prevent excessive post-operative blood loss.

Normal Mechanism of Hemostasis
Hemostasis is a complicated process.
It involves a number of events

Hemostasis - Normal Mechanism
1.  Vascular phase
2.  Platelet phase
3.  Coagulation phase

Vascular phase
When a blood vessel is damaged, vasoconstriction results.

Platelet phase
Platelets adhere to the damaged surface an form a temporary plug.
Through two separate pathways, the Intrinsic and Extrinsic, the conversion of fibrinogen to fibrin is complete. Fibrin tightly binds the platelets to form a clot

Coagulation phase

The clotting mechanism

Dependent upon:
  • Vessel Wall Integrity 
  • Adequate Numbers of Platelets 
  • Proper Functioning Platelets 
  • Adequate Levels of Clotting Factors 
  • Proper Function of Fibrinolytic Pathway
Hemorrhage in Oral Surgery
Hemorrhage following Oral Surgical procedures can occur due to local or systemic causes.
In healthy patients the postoperative bleeding is mainly due to local causes.

Local causes of hemorrhage in oral surgery
Local causes of hemorrhage originate in either soft tissue or bone.

Local causes of hemorrhage in oral surgery –Soft tissue bleeding
Soft tissue bleeding is either arterial, venous, or capillary in nature.

Arterial bleeding is bright red and spurting in nature.
Arteries in the soft tissues at risk during oral surgical procedures are the lies posterior portion of hard palate) greater palatine artery and the buccal artery (lies lateral to the retromolar pad)

Venous blood is dark red in color and flows steadily and heavily especially if the vein is large.

Capillary bleeding is bright red in color and is more of a minimal ooze.

Local causes – Osseous (Bony) bleeding in oral surgery
Troublesome bone bleeding originates either from nutrient canals in the alveolar region, central vessels, such as the inferior alveolar artery, or from central vascular lesions (Hemangioma or Vascular malformation)

Systemic causes of hemorrhage in oral surgery
Some patients with heriditary conditions such as hemophilia, Von Willebrand’s disease are susceptible for hemorrhage following oral surgical procedures.
Patients with thrombocytopenia (decreased platelet count) , Leukemia e.t.c., are also at risk of prolonged bleeding after surgery.

Patients with uncontrolled hypertension.
Patients with H/O prosthetic heart valve replacement, Stroke (Cerebrovascular accident) e.t.c., take oral anticoagulants like Aspirin or Warfarin to prevent the occurrence of a thromboembolic episode.
These patients are also at risk of prolonged severe bleeding during and after an oral surgical procedure.

Types of Hemorrhage - Primary Hemorrhage
This occurs during the surgery, as a result of injury like cutting or laceration of the  artery or bleeding from bone.
This also occurs when surgery is done in an infected area with a lot of granulation tissue.
It can also occur after a very short period of time  immediately after surgery.
This type of bleeding is really normal and can be controlled easily.

Types of Hemorrhage - Intermediate / Reactionary Hemorrhage
This type of bleeding occurs within a few hours after surgery.
This type of bleeding occurs as a result of failure of coagulation to occur (as in patients with systemic bleeding problems or those on anticoagulants)
Patients who have unknowingly disturbed / dislodged the clot are also prone for this type of bleeding.

Types of Hemorrhage - Secondary Hemorrhage
This occurs after 7 to 10 days after surgery. This is mainly due to partial division of blood vessel in combination with infection of the wound (Like patient’s who undergo radical neck dissection e.t.c.,).
This type of bleeding is not very frequently encountered after oral surgery procedures.

Management of Primary Hemorrhage in Normal patients
The management of bleeding during surgery (Primary bleeding) can be achieved by the following means,
  • Securing / ligation of blood vessels with silk sutures. 
  • Use of pressure swab to achieve hemostasis. 
  • Use of electrocautery to achieve hemostasis. 
  • Use of hemostatic agents like bone wax, surgicel,e.t.c., 
  • Hypotensive anaesthesia (G.A) and use of vasoconstrictors in L.A.
Local Measures  ( Synthetic Materials)
There are several materials that are commercially available that are used  locally for achieving adequate hemostasis.

Local Measures: Surgicel (Oxidised Regenerated Cellulose)

Local measures: Gelfoam with activated thrombin

Local Measures: Avitene (Microfibrillar Collagen)

Local Measures: Etik Collagen (Packed collagen)

Local Measures: Tranexamic acid 5%

Local Measures: Tranexamic acid 5% in Syringe

Local Measures: Irrigation of wound with Tranexamic acid

Local Measures: Suturing the wound

Local Measures: Pressure with oral packs

Management of Intermediate Hemorrhage in  Normal patients

The management of bleeding that occurs immediately after surgery (Reactionary bleeding) involves proper examination of the surgical wound to identify the site of bleeding (i.e ) from bone or soft tissue.
If bleeding is from bone then the hemostatic agents like bone wax or gelfoam is usually used.
If bleeding is from soft tissues then, ligation / cauterization of blood vessels along with the use of hemostatic agents like surgicel and suturing of the wound is carried out.

Management of Secondary Hemorrhage in  Normal patients

The management of this type of bleeding that occurs a few days after surgery involves the removal of any debris from the wound surface that promotes the infection of the wound.
Identify the source of bleeding and treat as would be done in a  patient with secondary bleeding.
Surgical stents can be placed over extraction sockets for stabilization of clot and prevention of  wound contamination.

Management of Hemorrhage in patients with  bleeding disorders / and those on anticoagulant therapy

The usual protocol involved in the treatment of this group of patients consists of pre-operative blood investigations and preoperative correction of the underlying deficiency (Replacement of Clotting factors / platelets) if any in these patients.
Subsequently, after this appropriate local measures are used to decrease the chances of post-operative bleeding.
Laboratory evaluation
  • Platelet count 
  • Bleeding time (bt) 
  • Prothrombin time (pt) 
  • Partial thromboplastin time (ptt) 
  • Thrombin time (tt)
Platelet count
Normal  100,000 - 400,000 cells/mm3 
< 100,000            Thrombocytopenia
50,000 - 100,000 Mild Thrombocytopenia
< 50,000              Severe Thrombocytopenia
Bleeding time
Provides assessment of platelet count and function
Normal value

Prothrombin time
Measures Effectiveness of the Extrinsic Pathway
Normal value
10-15 SECS

Partial thromboplastin time
Measures Effectiveness of the Intrinsic Pathway
Normal value
25-40 SECS

Thrombin time
Time for Thrombin To Convert  Fibrinogen to Fibrin
A Measure of Fibrinolytic Pathway
Normal value
9-13 SECS

Management of Hemorrhage in patients with uncontrolled hypertension.
This group of patients need appropriate medical consultation for initiation of medical treatment to decrease their Blood Pressure.
Thus once their B.P is controlled, then the bleeding decreases and with local measures the hemorrhage is controlled.

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