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The clotting factors:

Factor I: Fibrinigen.

Factor II: Prothrombin.
Factor III: Tissue thromboplastin (TPL).
Factor IV: Calcium ion.
Factor V: Proaccelerin.
Factor VII: Proconvertin (SPCA).
Factor VIII: Anti-hemophilic factor (AHF).
Factor IX: AHF- B. (PTC).
Factor X: Stuart's power factor.
Factor XI: AHF- C. (PTA).
Factor XI: Hageman or Glass factor.
Factor XIII: Fibrin stabilizing factor.

The clotting mechanism:

The extrinsic pathway

Tissue trauma

TPL

VII VIIa
TPL
Ca+2
X Xa

The clotting mechanism:

The Intrinsic pathway
Blood trauma
HMW. Kininogen
Kallikren
XII XIIa
HMW. Kininogen
XI XIa
VIIa (ext. pathway)
IX IXa
VIIIa + Ca+2
X Xa

Prothrombin Activator

IIa

The clotting mechanism:

The Common Pathway

X Xa
Platelets
Ca+2
Va
II IIa

Fibrinogen fibrin

XIII XIIIa

Dental management of patient with bleeding disorders

Detection of the Patient Who Is a "Bleeder"
History:
Bleeding problems in relatives.
Bleeding problems after operations and tooth extractions.
Bleeding problems after trauma.
Medications that may cause bleeding problems:
Aspirin.
Anticoagulants.
Long-term antibiotic therapy.

Dental management of patient with bleeding disorders

Detection of the Patient Who Is a "Bleeder"
History:
Presence of illnesses that may have associated bleeding problems:
Leukemia, why?
Liver disease, why?
Hemophilia, why?
Congenital heart disease, why?
Renal disease such as: uremia, why?
Spontaneous bleeding from nose, mouth, ears, and so on....

Dental management of patient with bleeding disorders

Detection of the Patient Who Is a "Bleeder"Examination findings:jaundice, pallor.Spiderangiomas.Ecchymoses.Petechiae.Oral ulcers.Hyper plastic gingival tissues.Heamarthrosis.Screening laboratory tests.      Surgical procedure—excessive bleeding following surgery may be first clue to underlying bleeding problem

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Prothrombin Time (PT):
It is activated by tissue thromboplastin.
Tests extrinsic and common pathways.
Control should be run.
Normal (11 to 15 seconds, depending on laboratory).
It is increased in the following cases:
Anticoagulant drug.
Deficiency of the Vit.K associated factors.
Patient with liver disease.

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Activated Partial Thromboplastin Time (APTT):
Initiated by phospholipids platelet substitute and activated by addition of contact activator (kaolin).
Tests intrinsic and common pathways.
Control should be run.
Normal (25 to 35 seconds, depending on laboratory).
It is increased in the following cases:
Deficiency in the factor VIII, X, XI, XII.
Patient with heparin therapy.

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Thrombin Time (Clotting Time):
Activated by thrombin.
Tests ability to form initial clot from fibrinogen.
Control should be run.
Normal (9 to 13 seconds).
It is increased in the following cases:
Fibrinogen deficiency or abnormality
Lack of prothrombin accelerator.
Hemophilia.

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Platelets Function Analyzer (PFA-IOO*):
Tests platelet function.
It is normal if adequate number of platelets of good quality present.
Normal value (60 to 120 seconds).
Platelet count:
Tests platelet phase for adequate number of platelets.
Normal value (140,000 to 400,000/mm3).
Clinical bleeding problem (spontaneous) can occur if less than 50,000/mm3 of the platelets.

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Bleeding Time (BT):
It will tests platelet function and vascular phase.
There are two methods:
Duke's method: from (3-9) minutes.
Ivy's method: more than (4) minutes.
It is increased in the following cases:
When there are defect in the vessels or platelets count and/or function.

Screening Laboratory Tests for the Detection of a Potential "Bleeder" Person:

Specific factor assays demonstrate reduced factor VIII:C in hemophilia A and factor IX in hemophilia B.
VWF multimeric analysis.
Detection of the antigen in the serum of the patient against the VWF and / or VIII.

Medical management

Replacement therapy:
Whole blood.
Packet R.B.C., by removing the plasma.
Platelet conc., each one unit composed of 50 ml, and each unit will rise the platelets 5000/ mm3
Fresh frozen plasma: source of the coagulation factors.
Cryoprecipitate: rich in the factor VIII.
Auto blood transfusion.

Medical management

Management of the VWD:
Most patients with vWD are most appropriately treated with DDAVP (1 - desamino - 8 - D - arginine vasopressin, desmopressin).
Desmopressin, a synthetic analogue of the Anti-Diuretic hormone (ADH) vasopressin, raises the plasma levels of endogenous factor VIII and VWF.

Medical management

Desmopressin increases about 3-5 fold for a short time after the administration the plasma levels of VWF in patients with a partial deficiency of VWF or of factor VIII in patients with mild hemophilia A, and also in healthy individuals and in patients with other bleeding disorders.
The increase in vWf results in a shortening of the bleeding time and the increase in factor VIII results in a shortening of the activated partial thromboplastin time.
Desmopressin is highly cost-effective.

Medical management

The average dose requested to treat a single bleeding episode in mild hemophilia A and VWD (20 mg) is at least 10 fold less expensive than the corresponding dose of factor VIII (1000-2000 U).
Most importantly, is has been estimated that desmopressin, used in the place of plasma derived factor VIII concentrates during the years preceding the outbreak of AIDS to treat hemorrhages in mild hemophilia A patients, could have spared many hemophiliacs from HIV infection.

Medical management

Route of administration and dose:
Intravenous infusion: 0.3 mg/kg diluted in 50/ml saline solution over 30 min.
Subcutaneous injection: 0.3 mg/kg.
Intranasal spray: 300 mg/kg (concentrated solution).

Medical management

Management of the hemophilia: Replacement of the missing factor is the key to therapy, taking into consideration the short in vivo half-life of factors VIII (8–12 hours) and IX (12–24 hours). Freeze-dried factor concentrates are stable and convenient to use but are derived from large donor pools. Recombinant factors VIII and IX are now available and will replace plasma-derived concentrates in the UK by 2006.

Medical management

Management of the hemophilia:
DDAVP combined with an anti fibrinolytic agent increases factor VIII levels in patients with mild hemophilia A and may be used to avoid treatment with blood products.
Anti fibrinolytic agents have also been combined with factor concentrates when bleeding is external (e.g. in dental extraction), but have not usually been used with factor IX concentrates (because of the risk of thrombosis) or in haematuria (because of the risk of clot retention).

Medical management

Management of the hemophilia:
Genetic counselling is an important aspect of care in families affected by hemophilia.
Direct defect analysis using DNA technology is now being used in carrier detection.
The management of patient with hemophilia who are to undergo surgical procedure:
Increase Factor VIII production, by DDAVP (In patients with mild forms of the disease this therapy may be sufficient).
Replace missing Factor VIII (Cryoprecipitate, Factor VIII, Fresh frozen plasma or purified forms of Factor VIII).

Medical management

Management of the hemophilia:
Unfortunately some individuals with hemophilia produce Factor VIII inhibitors.
In some cases the level of inhibitors is low and can be combated with high doses of Factor VIII. However, in others the inhibitors are induced in response to Factor VIII and this represents a problem. Inhibitors may be overcome by administering activated Factor IX or prothrombin complex concentrates.

Medical management

Management of the hemophilia:
Inhibit fibrinolysis.
Antifibrinolytic therapy is useful in the post-surgical phase to protect the formed blood clot. Agents used in this way include tranexamic acid and epsilon-amino caproic acid (EACA).
The tranxamic acid will inhibit the plasminogen activation and thus will interfere with the fibrinolysis. The dose are:
Orally as a tablet 500mg / 1x3.
Parentrally (I.V. or I.M.): 500mg / 5ml ampoule. 2-3 ampoule.

Medical management

Management of the hemophilia: The epsilon-amino caproic acid (EACA) has the same action.Dose:Orally as a tablet 500mg / 1x3.Parentrally (I.V): 250mg / ml ampoule. Given 1 – 1.5, 5, 30 gm/ day, but not exceed 30 gm / day. N.B. Christmas disease is not as common as hemophilia but is similar to the latter condition with the exception that the problem is reduced Factor IX action.
Management is the same as with Hemophilia A except that any replacement therapy is with Factor IX that is not present in cryoprecipitate.

Medical management

Anti coagulant therapy:
The patient need alteration in the dose for dental treatment to be perfomed & its made by the physician.
Note: do not stop the anti coagulant therapy immediately , due to the risk of the rebound thrombosis.

local measures to control bleeding:

Incision Planning:
In the performance of any operation it is mandatory to plan the various incisions so that unduly large blood-vessels are not severed.
It should be remembered that even in the normal patient hemorrhage may be profuse if the area to be incised is inflamed as a result of local infection.
This pre-supposes that the surgeon is adequately acquainted with the normal anatomy of the part.

local measures to control bleeding:

The Securing of Bleeding Vessels with Haemostats:
The most effective hemostats for use in oral surgery are the curved or straight Halsted' mosquito artery forceps and no incision should ever be made through the skin unless an adequate number of hemostats is available for immediate use.
Intra-orally the use of hemostats is somewhat limited.

local measures to control bleeding:

Mechanical methods:
These include the application of any modality of force that would counter act the hydrostatic pressure within the bleeding vessel until such time as a clot can form and occlude the orifice.
Pressure: Usually after an extraction the patient biting down on a dry sponge placed directly over the area can control hemorrhage.

local measures to control bleeding:

Homeostasis through the Application of Pressure with Swabs:
Hemorrhage should be controlled by pressure from swabs and this is undoubtedly the most effective method for almost all intra-oral wounds.
A dry gauze swab is packed into the wound over the bleeding area and digital pressure is maintained over the swab for a minimum of two and a half minutes.
Pressure is a simple but most effective method If of controlling hemorrhage.
The authors have witnessed bleeding from the maxillary artery successfully arrested in this manner.

local measures to control bleeding:

local measures to control bleeding:
Homeostasis through the Application of Pressure with Swabs:
Occasionally the hemorrhage shows a tendency to persist even after pressure with a dry swab for an adequate period of time. In such circumstances a pack of ribbon gauze soaked in Whitehead's varnish (benzoin 10 parts, storax 7-5 parts, balsam of Tolu 5 parts, iodoform 10 parts, and solvent ether to 100 parts).

local measures to control bleeding:

Splint:
It is advisable to fabricate a splint prior to surgery than can be wired in place or worn by the patient over the surgical area.
This will create pressure over the bleeding area and will stabilize tissues so that the inadvertent motions of eating and swallowing will not reactivate the bleeding in the capillary bed of the flap.
Splints are useful in patients who have preexisting blood dyscrasias and hemophilia and in patients who cannot leave the area alone, disrupting the clot following surgery.

local measures to control bleeding:

Bone Punch:

Ligaion and Sutures:

The use of absorbable gut for deep ties to ligate large vessels, and of silk or nylon sutures for surface constriction of a bleeding or oozing area, is good surgical practice.
It is important to use a traumatic needles whenever possible to prevent additional bleeding sites that may become troublesome in their own right.
Bone Wax.

local measures to control bleeding:

Haemostatic agents:
Epinephrine:
Epinephrine, (1:1000) concentration, applied locally with a piece of cotton or gauze, or injected locally in a concentration of (1:50000) for homeostasis, is quite effective, but its action is reversible.
This technique should not be used on patients with severe hypertension or previous existing cardiovascular disease.
The rationale for its use lies in the temporary arresting of bleeding long enough for a mechanical plug to clot or occlude the vessel.

local measures to control bleeding:

When the vasoconstrictor effect wears of ff the patient must be watched carefully for further recurrence of the bleeding, as the plug may become dislodged again.
Epinephrine, while a physiologic substance, is a very potent drug, and many patients have been known to suffer rather severe hypersensitivities to its topical use.
Monsel's Solution:
Monsel's solution of ferric sub sulfate may be used topically or on an area of capillary bleeding to precipitate the protein.
Effective for the post - extraction bleeding in medullary bone.

local measures to control bleeding:

Thrombin: Thrombin may be used the same way, and will act as a precipitating agent for the fibrin clot if there is fibrinogen present in the plasma. The topical (it must never be injected) use of thrombin is favored by many because of its physiologic compatibility to normal processes. Russell Viper Venom: Russell viper venom, a dry powder constituted with water, made in 5—ml ampules, is a preparation of thrombo-plastin that can be used similarly in a socket or topically over an area of bleeding to precipitate blood clot formation.

local measures to control bleeding:

Note: Monsel's solution, Russell viper venom, and thrombin should be used only on iodoform or plain gauze, cotton.
Tannic Acid:
The tannic acid in a tea bag will help precipitate protein and cause clot formation.
It is best applied by having the patient bite down on the folded tea bag, dry or very slightly moist, for five minutes, repeating, if necessary, three times.

local measures to control bleeding:

Gel foam, Absorbable Gelatin:
Gel foam is a medical device, intended for application to bleeding surfaces as a haemostatic. It is a water-insoluble, of white, non elastic, porous, pliable product prepared from Gelatin USP granules and Water for injection.
It is able to absorb and hold within its interstices, many times its weight of blood and other fluids. Gel foam sterile powder is a fine, dry, heat-sterilized light powder prepared by milling absorbable gelatin sponge. Gel foam sterile sponge may be cut without fraying.

local measures to control bleeding:

Contra-Indications:
Gel foam should not be used in closure of skin incisions because it may interfere with healing of the skin edges. This is due to mechanical interposition of gelatin and is not secondary to intrinsic interference with wound healing.
Gel foam should not be placed in intravascular compartments, because of the risk of embolization.
Adverse Reactions:
Gel foam may serve as a nidus for infection and abscess formation, and has been reported to potentiate bacterial growth.
Foreign body reactions, "encapsulation" of fluid and hematoma have also been reported.

local measures to control bleeding:

Oxycel:
Oxidized cellulose (Oxycel) releases cellulosic acid, which has a marked affinity for hemoglobin, leading to the formation of an artificial clot.
The action of Oxycel is not enhanced by the addition of thrombin or other hemostatie agents, for they are destroyed by the high acidity of this material. This product is not recommended for use over epithelial surfaces.

local measures to control bleeding:

Surgicel:
Oxidized regenerated cellulose (Surgicel) offers some improvement over Oxycel in that the gauze pad has more tenacity and resistance, and the poly- and hydroglutonic acids resulting from this product do not inhibit epithelialization.
It therefore can be used on surface dressings where epithelium is involved.
Ice:
Topical ice application, on five minutes on and five minutes off for the first four hours, sometimes will help reduce bleeding. However, some tests have shown this to be totally ineffective.

local measures to control bleeding:

Electrocautery:
There are many instances when bleeding of some size can be controlled by electrocautery through two modalities.
a. After securing a moderate-sized vessel with a hemostat, the cautery can be touched to the hemostat.
b. A more common use is to apply the cautery directly to small vessels that are oozing or bleeding. This will coagulate the blood and the protein in area.

Postoperative Haemorrhage:

Postoperative haemorrhage may be due:
Failure to control haemorrhage at the conclusion of the operation.
It comes under the heading of negligence and it causes great inconvenience to the patient, the nursing staff.
No wound should ever be sutured. Until adequate homeostasis has been effected.
Factors restarting Hemorrhage:
Hemorrhage may start again during the first few hours after the operation, due to:
Mechanical injury of the wound.
Application of heat to the wound inducing local hyperemia.

Postoperative Haemorrhage:

Postoperative haemorrhage may be due:
Factors restarting Hemorrhage:
Reactive hyperemia resulting as the effect of adrenaline wears off.
Violent exercise with general peripheral vasodilatation.
Rise in blood-pressure.
The consumption of a number of alcoholic drinks, perhaps for their analgesic or euphoric effect.
Coughing.
local measures to control bleeding:

local measures to control bleeding:

Postoperative haemorrhage may be due:
Infection at the Wound Site:
Secondary haemorrhage is usually due to a partial division of a blood vessel in combination with sepsis.
The sepsis alone rarely causes secondary hemorrhage, secondary hemorrhage on the classic tenth day should largely be of purely historical interest.

Bleeding from a Tooth Socket.

I think that your eyes now resembling this picture.



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