ORAL AND MAXILLOFACIAL SURGERY PDF

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Tenderness, discharge and lymphatic involvement are also impor 8 Principles of Oral and Maxillofacial Surgery surgeon will need to consult. Text book of Oral and Maxillofacial Surgery. 94 Anand et al Testicular abscesses exhibits increased flow on the dynamic phase images along with a non specific. In the second edition of the book a detailed and authoritative exposition of basic principles of oral and maxillofacial surgery is presented in.


Oral And Maxillofacial Surgery Pdf

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Ramdas Balakrishna BDS, MDS Oral and Maxillofacial Surgeon and . Armamentarium and their Usage in Oral and Maxillofacial Surgery 45 UNIT II. Many textbooks have been written over the years aiming to introduce students and resi- dents to the fundamentals of oral and maxillofacial surgery. Some of. Challenging Concepts in Oral and Maxillofacial Surgery presents 26 complex case scenarios that are mapped to the OMFS syllabus. These are intended to.

Cerebrovascular syncope Prodrome 1. Terminate all dental treatment Pathophysiology and Manifestation of 2. Position patient in supine position with legs Vasovagal Syncope raised above level of head. Attempt to calm patient 4. Monitor vital signs Syncopal Episode 1. Terminate all dental treatment 2. Position patient in supine position with legs raised 3. Management Shock 1. Maintain supine position with legs lifted above It is hemodynamic disturbance where there is head, therefore increased blood to brain.

Irreversible stage — — Decrease in blood pressure Type Cause Mechanism — Decrease in cardiac output 1. Hypovolaemic -Haemorrhage, -Decrease in blood — Tachypnea shock trauma volume — Decrease blood to vital organ and - fluid loss, specific features burns 2.

Cardiogenic - Myocardial -Decrease in — Can lead to death. Anaphylactic shock - Anaphylaxis -Peripheral vasodilatation and It can be easily prevented than treated: Supine position with head below the feet periphery should be positioned. Oxygen inhalation 3. Maintain airway, and it may need tracheostomy. Monitor vital signs 5. Maintain body heat by covering with blanket and hot packs. Restore lost body fluid. Treat cause and symptomatic relief should be provided.

Injection hydrocortisone and atropine sulphate, antibiotics, adrenaline. Tachyphylaxis It is the falling off in the effect produced by a drug during continuous use or constantly repeated administration. Features It is mainly seen in drugs of nervous Three stages in shock are: Progressive stage: Mild toxicity: Moderate toxicity: V nystagmus, tremors, — Place in supine position — administer diazepam headache, dizziness, — Monitor all vital signs.

Severe toxicity: Seizure, cardiac — if seizure occurs, protect — Transport to emergency dysrhythmia or arrest patient from nearby care facility.

Position patient in sitting posture. Bone wax on bone bleeding point. Postoperative Hemorrhage Causes Six reasons and difficulty to stop bleeding from extracted socket: In normal patients: The tissues of mouth and jaw are highly i. Intraoperative vascular — Incision 2. Extraction leads a open wound in soft tissue — Damage caused while using various and bone hemostatic techniques 3. Difficult to apply dressing material and proper ii.

Postoperative pressure and sealing to the intraoral sites. Patient tends to play with the surgical area, — reactionary therefore dislodges clot. Small negative pressure is created repeatedly 2. In diseased patients: Salivary enzymes lyse clot. This occurs generally due to infection varnish present in the area of surgery. Defer surgery after delivery if possible 2.

Avoid dental radiographs unless information about tooth roots or bone is necessary for proper dental care. If radiographs must be taken, use proper shielding. Avoid the use of drugs with teratogenic potential. Use local anesthetics when anesthesia is necessary. Use at least 50 percent oxygen if nitrous oxide sedation is used Fig.

Hemorrhage management 6. Avoid keeping the patient in the supine on applying pressure position for long periods, to prevent vena cava compression 7. Allow the patient to take frequent trips to the rest room. CPR can be administered outside hospital or in hospital. If it is done outside hospital, then cardio- pulmonary resuscitation is providing basic life support, but if it is done in hospital, then basic life support BLS as well as advanced care life support ACLS is also given.

Objectives The ABCs of life is maintained. Mouth to mouth breathing They are: Place the patient is supine position with head higher than the legs. Patency of the airway is checked iii.

Any obstruction in the airway by any foreign body is removed. Patients airway is opened by a head tilt-chin lift position. Administer mouth to mouth breathing Fig. Mouth to nose breathing or mouth to airway breathing, can also be given if mouth is seriously Fig. Chest compression injured or cannot be opened. External cardiac compressions are given to restore blood circulation. Antibiotics These are substances produced by micro Compression Method organisms that either retard the growth of or 1.

In case of 1 operator, 15 compressions with kill other micro-organisms at high dilution. If the pulse is absent, then CPR These are similar to antibiotics, except that they should be resumed Fig.

In case of 2 operators, 5 compressions with 1 ventilation is administered. Drugs inhibiting cell wall synthesis: The improvement of the patient during administ- — Penicillin ration of basic life support is evaluated by the — Cephalosporins colour of the skin and mucosa, chest size, pulse — Vancomycin rate, respiratory movements, and pupil of the — Cyclosporine eyes.

Drugs inhibiting protein synthesis: Extended spectrum penicillin — Drug binds to 30s ribosomal subunit: Drugs affecting cell permeability — Salbactam — Aminoglycoside — Tazobactum 4. Drugs affecting DNA Gyrase: Cephalosporin 5. Drugs interfering with DNA function: First generation against gram positive cocci — Rifampicin and gram negative aerobes — E. Coli, proteus — Metronidazole i. Oral 6. Drugs interfering with DNA synthesis: Drugs interfering with intermediate ii. Parenteral metabolism: Second generation against first generation — Pyrimethamine organism and H.

Parenteral — cefuroxime A. Penicillin — cefatetan 1. Natural penicillin — cefoxitin i. Benzyl penicillin 3. Third generation Neisseria, E. Sodium penicillin H. Depot penicillin procaine pen i. Oral 2. Semisynthetic penicillin — cefixine i. Acid resistant penicillin — cefprodoxine — phenoxy ethyl penicillin ii.

Parenteral — phenoxy methyl penicillin — ceftriaxone ii. Fourth generation gram positive, gram — cloxacillin negative, Pseudomonos iii. Broad spectrum penicillin Parenteral — Amoxycillin — cefipime — Ampicillin — cefpirome http: Short acting and thus preventing cell wall formation of i. Thus are bacteriocidal. Intermediate acting succeptible than gram negative. Thus inhibits are: Use of Opoid analgesic 3. Acupuncture patients.

Morphine ii. Hydroxodone 3. Naltrexone iii. Sodium salicylate http: Ibuprofen ii. Ketoprofen Contraindications 4. Phenylbutazone ii. Oxicams i. Piroxicam Classification ii. Meloxicam 1. Short acting Natural 8. Fenamate i. Hydrocortisone i. Mefanamic acid ii. Cortisone 9.

Furanones 2. Intermediate acting Synthetic i. Rofecoxib i. Prednisolone ii. Celecoxib ii. Methylprednisolone Sulfoanilide 3. Long acting Synthetic i. Nimesulide i. Beclamethasone Acetic acid ii. Betamethasone i. Diclofenac iii.

Dexamethasone Alkanone 4. Inhaled i. Nabumetone i. Benzoxazocine ii. Budesonide i. Nefopan iii. Fluticasone 5. Topical Mechanism of Action i. Betamethasone iv. Fluticasone Effects v. Pharmacological therapy Adverse Reactions i. Mineralocorticosteroid ii. Collagen disorder i. Sodium and water retention — Systemic lupus erythromatosis SLE ii. Edema — Discoid lupus erythromatosis DLE iii. Hypokalemic alkalosis — Nephritis syndrome iv. Progressive rise in blood pressure iii. Allergic disorders 2.

Hyperglycemia — Angioneuretic edema iii. Muscles weakness — Serum sickness iv. Susceptibility to infection iv. Autoimmune disorders v. Delayed wound healing — Pemphigus vi. Osteoporosis — Hepatitis vii. Peptic ulceration v. Bronchial asthma viii.

Psychiatric disturbance vi. Pulmonary edema ix. Growth retardation vii. Skin disease x. Suspension of hypothalamopitiutary axis. Shock and septicemia. Apthous ulcer ii. Desquamative gingivitis iv. Oral lichen planus Classification v. Oral pemphigus 1. Centrally acting vi. Postextraction edema. Pulp capping 2. Peripherally acting viii. Pulpotomy i. Competitive blockers. TMJ arthritis a. Intracanal medicament — Pancuronium.

Persistent depolarisers 5. Oxidized cellulose Oxycel: These are surgical — Scoline. Directly acting to control bleeding from extracted socket. Oxidized regenerated cellulose: These are Indications modified oxygel which does not retard epithelization. Microfibrillar collagen hemostat: I disturbances. Iron substances These are locally applied agents which causes Antibiotics Prophylaxis Regimens control in bleeding. Standard oral Amoxicillin 2 gm 1 hour vasoconstriction action.

It causes cardiac regimen before procedure abnormalities if absorbed systemically. Alternative regimen Clindamycin mg 1 hour 2. Prepared from human or bovine for patients allergic or before plasma, is used as a freeze — dried powder to amoxicillin, Azithromycin mg penicillin or both or 1 hour before or freshly prepared solution.

Used in cephalexin 2 g 1 hour before hemophilia, skin grafting and neurosurgery 3. Patients unable Ampicillin 2 g I. V but never given by injection as can cause to take oral within 30 min. Patients unable Clindamycin mg I. V within 3. Fibrin foam: Human fibrin is extracted, dried to take oral or 30 min. V within 30 min. Absolute gelatin foam gel foam: Absolute before procedure as powder or porous substance and is best http: Parenteral preparations: Oral preparations: Inhaled preparations: Oxygen iii.

Drug Interacting Drug Effect Seen 1. Antihistamine CNS depressants Increased drowsiness and sedation 2. Salicylates Asprin i. Anticoagulants dicoumarin — Increases anticoagulant effect, thus more bleeding ii.

Antacid — Decreases asprin action iii. Corticosteroids — Increase GI bleeding iv. Oral hypoglycemic — Increases hypoglycemic effect v. Phenytoin — Increases antiepileptic effect 3.

Atropine Alcohol — Increases drowsiness 4. Carbamazepine Barbiturates, doxycycline, steroids. Corticosteroid i. Antidiabetic drugs — Increases hypoglycemia action ii. Antihypersensitivity drug — Antagonism iii. Oral contraceptives — Increases anti-inflammatory actions 6. Cotrimoxazole i. Diuretics — Increases risk of thrombocytopenia ii. Anticoagulants, antiepileptic, oral hypoglycemic — Increases action of these drugs 7. Diazepam CNS depressants — Increases sedation effect 8.

Doxycycline i. Penicillin — Decreases penicillin action ii. Barbiturates and antiepileptic — Decreases drug effect 9. Metronidazole i. Alcohol — Antagonism ii. Antiepileptic — Increases phenytoin toxicity iii. Anticoagulants — Increases anticoagulant effect iv. Barbiturates — Decreases drug effect Penicillin Oral contraceptives — Increases bleeding Tetracyclines i. Oral contraceptives — Increases bleeding ii. Oral hypoglycemic agents — Increases hypoglycemic effect iii.

Methotrexate — Increases methotrexate toxicity http: Malamed SS — Handbook of medical emergen- cies in the dental office, 3rd ed, Harcourt, Brace, Asia — Malamed - Medical 6. Mc Carthy FM — Medical emergency in dentistry, emergencies in the dental office.

Hardman, Limbird, Gilman — Goodman and 7. The phar macological basis of oral and maxillofacial surgery, 4th ed Satoskar — Textbook of Pharmacology. KD Tripathi — Essentials of medical 9.

Tintinalli, Kalan, Stapczynski — Emergency pharmacology, 4th ed. Little, Falace, Miller, Rhodus — Dental management of the medically compromised patients, 6th ed These include scrubbing and Sterilization preparing of operational site. It is the process by which any article, surface or media is made free from all micro-organisms Infection either in the vegetative or in sporing state. It is the deposition of organisms in the tissue and Disinfection their growth resulting in a host reaction. It is the process by which the number of viable micro-organisms is reduced to an acceptable Cross Infection level, but may not inactivate some viruses and Transmission of infection among patients, bacterial spores.

It is a chemical substance which causes disinfec- tion. Sunlight It is done prior to sterilization and disinfection. Drying Asepsis 3. Filtration i. Membrane filters It is the avoidance of pathological organisms, ii. Rapid and slow sand filters methods to prevent contamination of wound iii.

Earthen and asbestos filters. Radiators with the area. Ionizing radiations ii. Non ionizing radiations. Antisepsis 5. Vibration It is the procedure or application of antiseptic i. Sonic vibration solution.

This inhibits micro-organisms growth ii. Ultrasonic vibration http: It works on the principles of a ii. For light load of instruments: Alcohol Temperature: For wrapped instruments: Aldehyde Temperature: Dyes — Aniline Advantages — Acryline It is a rapid and most effective procedure for 4.

Halogens sterilization of cloth, surgical packs and towel — Iodide packs where other methods cannot be used. Phenol — Cresol Disadvantages — Chlorhexidine Items sensitive to high temperature cannot be 6. Gases used.

This method can rust carbon steel instru- — Ethylene oxide ments and leads to coagulation of powder items. Surface active agents — Cationic salts — Anionic salts — Non-ionic salts. For a room of cc a box of gm KMnO4 potassium permanganate and ml of formalin is mixed and kept. Formaldehyde gas is released which is allowed to circulate in the closed room for hrs after which the gas is allowed to escape before being used. Autoclave http: Half hour cycle Parameter Used Pressure: But, sterilization as it does not kill spores.

It is used ethylene oxide is hazardous for certain in cases where autoclaving or other methods are instruments and even for some patients. It destroys the blood borne pathogens. Pressure cookers etc are similar Parameters Used as it increases the temperature and creates condition similar to that in an autoclave. Conventional Method Temperature: They usually cleaned of blood and debris before sterilization provide larger space at low cost.

They may not strictly followed for its operation and be automatically timed. Draping of operator: A Drape is held straight before wearing; B First right side is draped followed by the left; C The nurse tightens the drape in position http: A The cuff of the right hand gloves is held and worn first; B and C The left hand cuff is held followed by complete gloving of the operator Fig. Daniel M Laskin — Oral and maxillofacial surgery. The biomedical and clinical basis for surgical 1. Microbiology, 7th ed.

Peterson, Ellis, Hupp and Tucker — 3. Darby and Walsh — Dental hygeine theory and Contemporary oral and maxillofacial surgery, 4th practice, 2nd ed. Explorer dental probe Mouth Mirror Fig. In cartridge syringes metal and plastic anesthetic cartridges are used.

Mouth mirror different sizes and contain a luer lock screw on needle attachment but no aspiring Dissection Forceps Fig. Cartridge syringe Fig. Dissection forceps college type Sponge Holder Fig. Plastic disposable syringe http: Blades are angulated. No ratchet at handle.

The Fig. Cheatel forceps blades are made in a variety of widths and lengths. Towel Clip Fig. Upper pre-molars Dental Extraction Forceps Fig. Upper pre-molar anterior both right and left. Left upper molar dental extraction forceps Bayonet Forceps upper root Fig.

Upper third molar forceps http: E junction or mirror image in badly decayed tooth. Lower anterior dental extraction forceps Fig. Lower pre-molar root forceps http: Lower molar dental extraction forceps Fig. Root separator lower Coleman Elevator separated blade Fig. Coleman elevator separated blade Fig. Lendo levien elevator http: Warwick james elevator Hospital Pattern Elevator Fig. Hospital pattern elevator Moon's Probe Fig. Warwick James Elevator Fig. The handles are flattened elongated and non- Fig.

The blades are small and smooth. One with straight blade and two with curved Dental Mouth Prop Fig. Ward periosteal elevator Fig. Dental mouth prop. Periosteal Elevator Fig. Periosteal elevator — No. They are divided into groups according to the tissue concerned. Kay's Modified Austin Retractor Fig. Surgical blades from operative field. Howarth Periosteal Elevator Fig. Howarth periosteal elevator Fig. Rowe maxillary labial retractor Langenbeck Retractor Fig.

Ward cheek retractor wisdom tooth Aufright Retractor Fig. Langenbeck retractor Cheek Retractor Fig. Aufright retractor Jenkin's Chisel Fig. Cheek retractor flat surfaces, one of which is beveled to meet http: It other and cutting edge is at one side and is used with mallet.

McIndoe nasal chisel Fig. Gillies Osteotome Fig. Kelsey Fry mallet meet each other to form a wedge. Cutting edge is in the centre.

It is used with mallet Surgical Burs Fig. Gillies osteotome Jenkin's Gouge Fig. Volcanite Burs Fig. Volcanite burs http: Fickling forceps angled Fig. Ward rongeurs double action Alli's Tissue Forceps Fig. Bone shears Read curette Fig. Bone file alveolecting Fig.

Read curette http: Available in various shapes with either cutting or reverse cutting or round bodied with eyes, closed or frenched type or swaged. Gillics scissors and needle holders No rachets Fig. Suture needles Fig. Myo needle holder with rachets Dissection Forceps toothed Figs 5. The tip is used for grasping the mucosal flaps while suturing or to hold the suture needle.

Gillics dissecting forceps toothed Fig. Suturing needles Needle Holder Fig. Variations are to be found in those with or without ratchets. One blade perforated for end holding of needles. Inside criss cross striation Fig. Adson fissure forceps with central groove on opening. Some times come with scissors behind the blades. Non-toothed Dissecting Forceps Fig.

Non-toothed dissecting forceps http: Straight or curved. Forceps curved crile artery Fig. Scissors Artery Forceps Figs 5. Either curved or straight. Has tranverse Fig. Mosquito artery forceps serration on the inner aspect of blades.

Ratchets present. Lister Sinus Forceps Fig. Forceps Straight crile artery Fig. Lister sinus forceps http: Gillies skin hook Fig. Presence of ratchet in handle. For example, Halo head frame, Andre charest head frame, Crawford head frame. Hayton Williams wire twister Wire Cutter Fig. Hallow frame Walshan's forceps Figs 5. It is a set of two forceps right and left. One blade of the forceps is Fig. Wire cutter designed to be inserted into the nasal cavity and http: Septal forceps: Have straight flat oval ended blades, which is applied one on either side of the nasal septum to straighten the nasal septum.

Malar bone elevators http: Obwegessor's Ramus Retractor Fig. They are applied between teeth. Chin retractor suction speed. Volkmann's Bone Scoop Fig. Bone scoop drainage. Multiple holes are usually made in the drain to prevent the drain from getting Bone Spreader Fig. It is secured to spring action when the handles are the skin by sutures. The purpose of this tube is to ventilate the airway during general anesthesia. Bone spreader hooks incorporated on it.

It is malleable and can be adapted to the contour of maxillary Suction Tips Fazier type Fig. The nose during rhinoplasty blunt end is passed through the nostril into the stomach. To check the position of the tube air is pushed into the tube with the help of a syringe and checked in stomach with stethoscope. At the for suturing of tissues after any procedure other end of the catheter two tubes are or trauma. The wider tube is meant for draining the urine and the narrower communicates Ideal Properties of a Suture Material with the balloon.

Classification of Suture Material 1. Absorbable i. Natural - catgut - collagen tape Fig. Catheter - tensor fascia lata ii. Non absorbable outer tube. The curvature of the tube is such i. Natural that it does not damage the trachea. Synthetic Continuous suture- rapid water tight closure of - Nylon areas is there and tension is uniformly distributed - Dacron over the suture.

Catgut is a multifilamentous suture material, twisted mechanically and polished to make it appear monofilamentous. The material is numbered from to depending on its thickness. Plain catgut has poor knot properties and poor tensile strength, thus Chromic catgut made by addition of Horizontal mattress suture- chromium salt at time of manufacturing is used to increase its tensile strength and knot properties. It also prolongs absorption time and reduces tissue reaction.

Catgut is stored in isopropyl alcohol which is a storage media and also softens it. Before using the catgut, it should Continuous horizontal mattress suture- be washed thoroughly with saline water to prevent from causing irritation. Types of Suturing Used in Dentistry Interrupted suture- earliest and mostly used. Can be used in areas of infection and loosening of Vertical mattress suture- done to close deep one suture does not produce loosening of other wounds.

The needle holder should grasp the needle at approximately three-fourth of the distance from the point. The needle should enter the tissue perpendicular to the surface. The needle should be passed through the Subcuticular suture- tissue following the curve of the needle.

Anchor suture- 4. The suture should be placed at an equal Continuous independent suture- distance 2 to 3 mm from the incision on both sides and at an equal depth Types of Knot Used Figs 5.

If one tissue side is free and other fixed, the needle should be passed from the free to the fixed side. Square knot Position of holding needle and method of holding forceps Surgeon's knot Insertion of needle along with curvature Granny's knot Position of knot-at thw side http: If one tissue side is thinner than the other, Sutures should be placed approximately the needle should be passed from the 3 to 4 mm apart.

Extra tissue should be excised to prevent 7. If one tissue plan is deeper than the other, 'Dog Ear' formation and other unsatisfactory the needle should be passed from the results. Archer WH — Oral and maxillofacial surgery, distance from the tissue edge. The tissue should not be closed under 2. Danial M Laskin — Oral and maxillofacial surgery. The suture should be tied so the tissue is 3.

Gustov O Kruger — Textbook of oral and The knot should not be placed over the maxillofacial surgery, 6th ed. Peterson, Ellis, Hupp, Tucker — Contemporary oral and maxillofacial surgery, 4th ed, Anesthesia may occur transmit impulses towards the nerve cell body.

This is affected by administering The axon is the longest process of the nerve cell. The axon or hypnosis. To understand about these may extend for a long distance away from the procedures one has to briefly understand about nerve cell body. The length of the longest axon the cause and physiology of pain. Nerve fibres are of two kinds: Non-myelinated nerve fibres: In these fibres The neuron is made up of three parts Fig.

Nerve cell body called neurolemma. The speed of nerve 2. Dendrite and impulse conduction in these fibres is less. Myelinated nerve fibres Fig 6. In these fibres the axis cylinder is covered by a thick Nerve Cell Body sheath called myelin sheath which is in turn covered by neurolemma. The speed of The nerve cell body is irregular in shape and, nerve impulse conduction in these fibres are like any other cell it is constituted by a mass of more due to the saltatory jumping type of cytoplasm called as neuroplasm covered by a conduction occurring in them.

On getting excited by The dendrites are the branched processes of the an impulse they change to depolarized state neuron and are branched repeatedly.

The which further changes to repolarised state and dendrites have Nissl granules and neurofibrils. At difference across the membrane of mV to the time of depolarization no new impulse mV. Resting potential Fig. Whereas the time during which Depolarised State repolarisation is occurring only impulse with stronger, potential can be transmitted, this is called relative refractory period Fig.

This alters potential gets crossed for more number of fibres. Lateral reticular Pain has dual nature: Nucleus formation 1. Pain perception: It is a physio-anatomic process were impulse is generated as Median reticular formation transmitted.

Pain reaction: It is a psycho-physiological Dorsal root ganglion Pain process where indivisual feels and senses pain. Pain Theories 1. Specific theory: Specific mediator of touch, heat, cold and pain are present on skin and from here specific sensory nerve takes the impulse to specific site or pain centre in the brain where it is interpreted.

Pattern theory: Pain is dependent upon specific pattern of nerve impulse produced by summation of sensory input within spinal cord. Gate control theory: Peripheral nerves carry impulse from skin to CNS, larger nerves also help in exciting or inhibing the impulse. Descending control system modulates the excitation of cells and tissues and thus transmitted information about injury. The two roots are attached to lower adjacent structures to the semilunar ganglion.

Journal of Oral and Maxillofacial Surgery

Terminal branches in the parotid gland: Temporal nerve supplies the auricularis, vessels. Zygomatic nerve supplies the orbicularis divided into three parts by two bends: Buccal nerve the upper buccal nerve 2nd part—near middle ear, above the supplies the parotid duct.

Mandibular nerve supplies muscles of 3rd part—behind the promontory lower lip and chin The first bend is sharp; near the v. Cervical nerve supplies the platysma anteriosuperior part of the promontory also called the Genu and contains the geniculate Trigeminal Nerve Neurology ganglion. It is the largest cranial nerve contains both The second bend is gradual and lies in sensory and motor fibres.

It is the sensory nerve between the promontory and aditus of the ear. The facial nerve leaves the skull through the stylomastoid foramen. In its extracranial course, Sensory Root the facial nerve crosses the base of the styloid process and enters the parotid gland. It then It arises from the semilunar ganglion.

The crosses the retromandibular vein and external ganglion forms two processes—Central and carotid artery and behind the neck of the Peripheral. The peripheral branches to form mandible it divides into five terminal branches ophthalmic, maxillary and mandibular division which emerge along the parotid gland. The central branches are the sensory roots of the trigeminal nerve. Within the facial canal: This is consists of fibres that arise in the motor i. Greater petrosal nerve supplies the nucleus located in the pons.

The filament passes lacrimal gland and the mucosal glands of from the pons along the medial side of semilunar nose, palate, pharynx ganglion and passes below the foramen ovale ii. Nerve to the stapedius supplies the and joins the mandibular division of sensory root. Chorda tympani supplies the submandi- called as masticator nerve.

They accompany the fibres of motor root. Posterior auricular nerve supplies the auricularis and occipitalis Branches of the Trigeminal Nerve ii.

Digastric nerve supplies posterior belly of digastric muscle A. Ophthalmic division iii. Stylohyoid nerve supplies stylohyoid 1. Lacrimal nerve supplies the lacrimal gland muscle. Frontal nerve supplies the frontal sinus c. Posterior superior alveolar nerve supplies a. Supraorbital nerve supplies the upper all the maxillary molars except for the eyelid, scalp and forehead mesiobuccal root of the maxillary 1st b.

Supratrochlear nerve supplies the skin molar, also the upper gingiva and of the upper eyelid, median portion of adjoining parts of the cheek.

Branches in the infraorbital groove: Nasociliary nerve i. Middle superior alveolar nerve a. Branches in the nasal cavity supplies the maxillary premolars b. Branches in the face ii. Ordinarily, apoptosis or programmed cell death is responsible for the removal of inflammatory cells as healing proceeds and for the evolution of granulation tissue into scar. Dysregulation in apoptosis results in excessive scarring, inflammation, and an overproduction of extracellular matrix components.

Additionally, proliferative scar tissue exhibits increased numbers of neoangiogenesis-promoting vasoactive mediators as well as histamine-secreting mast cells capable of stimulating fibrous tissue growth.

Although there is no effective therapy for keloids, the more common methods for preventing or treating these lesions focus on inhibiting protein synthesis. These agents, primarily corticosteroids, are injected into the scar to decrease fibroblast proliferation, decrease angiogenesis, and inhibit collagen synthesis and extracellular matrix protein synthesis. Optimizing Wound Healing At its very essence the wound represents an extreme disruption of the cellular microenvironment.

Restoration of constant internal conditions or homeostasis at the cellular level is a constant undertow of the healing response. A variety of local and systemic factors can impede healing, and the informed surgeon can anticipate and, where possible, proactively address these barriers to healing so that wound repair can progress normally. Tissue Trauma Minimizing surgical trauma to the tissues helps promote faster healing and should be a central consideration at every stage of the surgical procedure, from placement of the incision to suturing of the wound.

Properly planned, the surgical incision is just long enough to allow optimum exposure and adequate operating space. The incision should be made with one clean consistent stroke of evenly applied pressure. Sharp tissue dissection and carefully placed retractors further minimize tissue injury. Sutures are useful for holding the severed tissues in apposition until the wound has healed enough.

However, sutures should be used judiciously as they have the ability to add to the risk of infection and are capable of strangulating the tissues if applied too tightly. Wound Dehiscence Partial or total separation of the wound margins may manifest within the first week after surgery. Most instances of wound dehiscence result from tissue fail-. Achieving complete hemostasis before wound closure helps prevent the formation of a hematoma postoperatively.

The collection of blood or serum at the wound site provides an ideal medium for the growth of microorganisms that cause infection. Additionally, hematomas can result in necrosis of overlying flaps. However, hemostatic techniques must not be used too aggressively during surgery as the resulting tissue damage can prolong healing time.

Postoperatively the surgeon may insert a drain or apply a pressure dressing to help eliminate dead space in the wound. A necrotic burden allowed to persist in the wound can prolong the inflammatory response, mechanically obstruct the process of wound healing, and impede reepithelialization. The surgeon should also keep in mind that prosthetic grafts and implants, despite refinements in biocompatibility, can incite varying degrees of foreign body reaction and adversely impact the healing process.

Tissue Perfusion Poor tissue perfusion is one of the main barriers to healing inasmuch as tissue. Relative hypoxia in the region of injury stimulates a fibroblastic response and helps mobilize other cellular elements of repair. Cell lysis follows, with releases of proteases and glycosidases and subsequent digestion of extracellular matrix.

Neutrophils are affected because they require a minimal level of oxygen tension to exert their bactericidal effect. Delayed movement of neutrophils, opsonins, and the other mediators of inflammation to the wound site further diminishes the effectiveness of the phagocytic defense system and allows colonizing bacteria to proliferate.

Collagen synthesis is dependent on oxygen delivery to the site, which in turn affects wound tensile strength. Most healing problems associated with diabetes mellitus, irradiation, small vessel atherosclerosis, chronic infection, and altered cardiopulmonary status can be attributed to local tissue ischemia.

Similarly, tissue ischemia produced by tight or improperly placed sutures, poorly designed flaps, hypovolemia, anemia, and peripheral vascular disease, all adversely affect wound healing. Smoking is a common contributor to decreased tissue oxygenation. Smoking also increases carboxyhemoglobin, increases platelet aggregation, increases blood viscosity, decreases collagen deposition, and decreases prostacyclin formation, all of which negatively affect wound healing.

Patient optimization, in the case of smokers, may require that the patient abstain from smoking for a minimum of 1 week before and after surgical procedures. Another way of improving tissue oxygenation is the use of systemic hyperbaric oxygen HBO therapy to induce the growth of new blood vessels and facilitate increased flow of oxygenated blood to the wound.

Diabetes Numerous studies have demonstrated that the higher incidence of wound infection associated with diabetes has less to do with the patient having diabetes and more to do with hyperglycemia. Simply put, a patient with well-controlled diabetes may not be at a greater risk for wound healing problems than a nondiabetic patient.

Tissue hyperglycemia impacts every aspect of wound healing by adversely affecting the immune system including neutrophil and lymphocyte function, chemotaxis, and phagocytosis. The hemoglobin release of oxygen is impaired, resulting in oxygen and nutrient deficiency in the healing wound.

The wound ischemia and impaired recruitment of cells resulting from the small vessel occlusive disease renders the wound vulnerable to bacterial and fungal infections. Immunocompromise The immune response directs the healing response and protects the wound from infection. In the absence of an adequate immune response, surgical outcomes are. An important assessment parameter is total lymphocyte count. A mild deficit is a lymphocytic level between 1, and 1,, and levels below are considered severe total lymphocyte deficits.

Patients with debilitated immune response include human immunodeficiency virus HIV -infected patients in advanced stages of the disease, patients on immunosuppressive therapy, and those taking high-dose steroids for extended periods. The use of steroids, such as prednisone, is a typical example of how suppression of the innate inflammatory process also increases wound healing complications.

Exogenous corticosteroids diminish prolyl hydroxylase and lysyl oxidase activity, depressing fibroplasias, collagen formation, and neovascularity. Epithelialization and wound contraction are also impaired. The inhibitory effects of glucocorticosteriods can be attenuated to some extent by vitamin A given concurrently.

The reduction in protein synthesis or cell division reveals itself as impaired proliferation of fibroblasts and collagen formation. Attendant neutropenia also predisposes to wound infection by prolonging the inflammatory phase of wound healing. Because of their deleterious effect on wound healing, administration of antineoplastic drugs should be restricted, when possible, until such time that the potential for healing complications has passed.

Oral & Maxillofacial Surgery

Radiation Injury Therapeutic radiation for head and neck tumors inevitably produces collateral damage in adjacent tissue and reduces its capacity for regeneration and repair. The pathologic processes of radiation injury start right away; however, the clinical and histologic features may not become apparent for weeks, months, or even years after treatment.

Early acute changes are observed within a few weeks of treatment and primarily involve cells with a high turnover rate. The common symptoms of oral mucositis and dermatitis result from loss of functional cells and temporary lack of replacement from the pools of rapidly proliferating cells. The inflammatory response is largely mediated by cytokines activated by the radiation injury.

Overall the response has the features of wound healing; waves of cytokines are produced in an attempt to heal the radiation injury. The cytokines lead to an adaptive response in the surrounding tissue, cause cellular infiltration, and promote collagen deposition. Damage to local vasculature is exacerbated by leukocyte adhesion to endothelial cells and the formation of thrombi that block the vascular lumen, further depriving the cells that depend on the vessels.

The acute symptoms eventually start to subside as the constitutive cells gradually recover their proliferative abilities. However, these early symptoms may not be apparent in some tissues such as bone, where cumulative progressive effects of radiation can precipitate acute breakdown of tissue many years after therapy.

The late effects of radiation are permanent and directly related to higher doses. Once these changes occur they are irreversible and do not change with time.

Hence, the surgeon must always anticipate the possibility of a complicated healing following surgery or traumatic injury in irradiated tissue. Wound dehiscence is common and the wound heals slowly or incompletely. Even minor trauma may result in ulceration and colonization by opportunistic bacteria. If the patient cannot mount an effective inflammatory response, progressive necrosis of the tissues may follow.

Healing can be achieved only by excising all nonvital tissue and covering the bed with a well-vascularized graft. Due to the relative hypoxia at the irradiated site, tissue with intact blood supply needs to be brought in to provide both oxygen and the cells necessary for inflammation and healing.

The progressive obliteration of blood vessels makes bone particularly vulnerable. Following trauma or disintegration of the soft tissue cover due to inflammatory reaction, healing does not occur because irradiated marrow cannot form granulation tissue. In such instances the avascular bone needs to be removed down to the healthy portion to allow healing to proceed.

Hyperbaric Oxygen Therapy HBO therapy is based on the concept that low tissue oxygen tension, typically a partial pressure of oxygen PO2 of 5 to 20 mm Hg, leads to anaerobic cellular metabolism, increase in tissue lactate, and a decrease in pH, all of which inhibit wound healing. The HBO therapy is repeated daily for 3 to 10 weeks. HBO increases the quantity of dissolved oxygen and the driving pressure for oxygen diffusion into the tissue. Correspondingly the oxygen diffusion distance.

The therapy stimulates the growth of fibroblasts and vascular endothelial cells, increases tissue vascularization, enhances the killing ability of leukocytes, and is lethal for anaerobic bacteria. Clinical studies suggest that HBO therapy can be an effective adjunct in the management of diabetic wounds. However, in the absence of controlled scientific studies with well-defined end points, HBO therapy remains a controversial aspect of surgical practice.

Age In general wound healing is faster in the young and protracted in the elderly.

Introduction

The decline in healing response results from the gradual reduction of tissue metabolism as one ages, which may itself be a manifestation of decreased circulatory efficiency. The major components of the healing response in aging skin or mucosa are deficient or damaged with progressive injuries.

In addition the regional vascular support may be subjected to extrinsic deterioration and systemic disease decompensation, resulting in poor perfusion capability. Nutrition Adequate nutrition is important for normal repair. Dietary protein has. Amino acids are critical for wound healing with methionine, histidine, and arginine playing important roles. As long as a state of protein catabolism exists, the wound will be very slow to heal. Methionine appears to be the key amino acid in wound healing.

It is metabolized to cysteine, which plays a vital role in the inflammatory, proliferative, and remodeling phases of wound healing.

Serum prealbumin is commonly used as an assessment parameter for protein. As such it provides a more rapid assessment ability. Normal serum prealbumin is about As part of the perioperative optimization process, malnourished patients may be provided with solutions that have been supplemented with amino acids such as glutamine to promote improved mucosal structure and function and to enhance whole-body nitrogen kinetics.

An absence of essential building blocks obviously thwarts normal repair, but the reverse is not necessarily true.

Whereas a minimum protein intake is important for healing, a high protein diet does not shorten the time required for healing. Several vitamins and trace minerals play a significant role in wound healing. Healing wounds appear to be more sensitive to ascorbate deficiency than uninjured tissue. Increased rates of collagen turnover persist for a long time, and healed wounds may rupture when the individual becomes scorbutic. Local antibacterial defenses are also impaired because ascorbic acid is also necessary for neutrophil superoxide production.

The B-complex vitamins and cobalt are essential cofactors in antibody formation, white blood cell function, and bacterial resistance. Depleted serum levels of micronutrients, including magnesium, copper, calcium, iron, and zinc, affect collagen synthesis.

Zinc deficiency retards both fibroplasia and reepithelialization; cells migrate normally but do not undergo mitosis. On the other hand, exceeding the zinc levels can exert a distinctly harmful effect on healing by inhibiting macrophage migration and interfering with collagen cross-linking. Advances in Wound Care An increased understanding of the wound healing processes has generated heightened interest in manipulating the wound microenvironment to facilitate healing.

Traditional passive ways of treating surgical wounds are rapidly giving way to approaches that actively modulate wound healing.

Therapeutic interventions range from treatments that selectively jumpstart the wound into the healing cascade, to methods that mechanically protect the wound or increase oxygenation and perfusion of the local tissues. Growth Factors Through their central ability to orchestrate the various cellular activities that underscore inflammation and healing,. However, the potential of these extrinsic agents has not yet been realized clinically and may relate to figuring out which growth factors to put into the wound, and when and at what dose.

To date only a single growth factor, recombinant human platelet-derived growth factor-BB PDGF-BB , has been approved by the United States Food and Drug Administration for the treatment of cutaneous ulcers, specifically diabetic foot ulcers.

Peterson's Principles of Oral and Maxillofacial Surgery 2nd Ed 2004

Results from several controlled clinical trials show that PDGF-BB gel was effective in healing diabetic ulcers in lower extremities and significantly decreased healing time when compared to the placebo group.

It enhanced both the formation of granulation tissue in rabbits and wound closure of the human meshed skin graft explanted on athymic nude rats. Several growth factors belonging to the neurotrophin family have been implicated in the maintenance and repair of nerves. Nerve growth factor NGF , synthesized by Schwann cells distal to the site of injury, aids in the survival and development of sensory nerves.

This finding has led some investigators to suggest that exogenous NGF application may assist in peripheral nerve regeneration following injury. Osteoinductive growth factors hold special appeal to surgeons for their ability to promote the formation of new bone.

Advances in recombinant DNA techniques now allow the production of these biomolecules in quantities large enough for routine clinical applications.

In particular, recombinant human bone morphogenetic protein-2 rhBMP-2 and rhBMP-7 have been studied extensively for their ability to induce undifferentiated mesenchymal cells to differentiate into osteoblasts osteoinduction. Similarly, Toriumi and colleagues showed that rhBMP-2 could heal mandibular defects with bone formed by the intramembranous pathway.

Genes encoding for select growth factors are delivered to the site of injury using a variety of viral, chemical, electrical, or mechanical methods. The more popular methods for transfecting wounds involve the in vivo use of adenoviral vectors. Existing gene therapy technology is capable of expressing a number of modulatory proteins at the physiologic or supraphysiologic range for up to 2 weeks.

Numerous experimental studies have demonstrated the use of gene therapy in stimulating bone formation and regeneration. Mesenchymal cells transfected with adenovirus-hBMP-2 cDNA have been shown to be capable of forming bone when injected intramuscularly in the thighs of rodents. These early studies suggest that advances in gene therapy technology can be used to facilitate healing of bone and other tissues and may lead to better and less invasive reconstructive procedures in the near future.

Dermal and Mucosal Substitutes Immediate wound coverage is critical for accelerated wound healing. The coverage protects the wound from water loss, drying, and mechanical injury. Although autologous grafts remain the standard for replacing dermal mucosal surfaces, a number of bioengineered substitutes are finding their.

Gene Therapy The application of gene therapy to wound healing has been driven by the desire to selectively express a growth factor for controlled periods of time at the site of tissue injury. The human skin substitutes available are grouped into three major types and serve as excellent alternatives to autografts. The first type consists of grafts of cultured epidermal cells with no dermal components.

The second type has only dermal components. The third type consists of a bilayer of both dermal and epidermal elements. The chief effect of most skin replacements is to promote wound healing by stimulating the recipient host to produce a variety of wound healing cytokines.

The use of cultured skin to cover wounds is particularly attractive inasmuch as the living cells already know how to produce growth factors at the right time and in the right amounts.

The ultimate goal of bioengineers is to develop engineered skin that contains all of the components necessary to modulate healing and allow for wound healing with a surrogate that replicates native tissue and limits scar formation.

References 1. Cutaneous wound healing. N Engl J Med. Cellular, biochemical, and clinical aspects of wound healing. Surg Infect Larchmt ;3 Suppl 1: Clark RAF.

Biology of dermal wound repair. Dermatol Clin ; Steed DL. Wound-healing trajectories. Surg Clin North Am ; Werner S, Grose R. Regulation of wound healing by growth factors and cytokines. Physiol Rev ; TGF-beta and macrophages in the rise and fall of inflammation. TGF-beta and related cytokines in inflammation. Birkhauser; TGF-beta superfamily cytokines in wound healing.

Ultrastructure and cellular biology of nerve regeneration. J Reconstr Microsurg ; Sunderland S. A classification of peripheral nerve injuries producing loss of function. Brain ; Factors influencing the course of regeneration and the quality of the recovery after nerve suture. Fu SY, Gordon T. The cellular and molecular basis of peripheral nerve regeneration. Mol Neurobiol ;14 1—2: Jilka RL. Biology of the basic multicellular unit and the pathophysiology of osteoporosis. Med Pediatr Oncol ; Frost HM.

A brief review for orthopedic surgeons: J Orthop Sci ;3: Anat Rec ; A histopathologic study of extraction wounds in dogs. Muller W. Split skin and full-thickness skin grafts. Mund Kiefer Gesichtschir ;4 Suppl 1: Skin grafts. Otolaryngol Clin North Am ; Kingsley A. The wound infection continuum and its application to clinical practice. Ostomy Wound Manage ;49 Suppl 7A: Biology of surgical infection.

Ravitch MM, editor. Current problems in surgery. Chicago IL: Yearbook Medical Publishers; Bowler PG. The bacterial growth guideline: Ostomy Wound Manage ; 49 1: Fibroproliferative scars. Clin Plast Surg ;30 1: Keloids and hypertrophic scars: Semin Cutan Med Surg ; Impairments to wound healing. Clin Plast Surg ; Wound pathophysiology, infection and therapeutic options. Ann Med ; Physiology of wound healing.

Adv Skin Wound Care ;13 Suppl 2: Anaerobic metabolism and wound healing: Am J Surg ; Tissue oxygenation, anemia, and perfusion in.

Ann Surg ; Gottrup F. Oxygen, wound healing and the development of infection. Present status. Eur J Surg ; Clearing the smoke: Plast Reconstr Surg ; Wound healing in well-controlled diabetic men.

Surg Forum ; Burns J, Pieper B. Ostomy Wound Manage ;46 3: Dig Surg ; Anstead GM. Steroids, retinoids, and wound healing. Adv Wound Care ; Effects of radiation on normal tissue: Lancet Oncol ;4: Radiother Oncol ; Tibbs MK.

Wound healing following radiation therapy: Radiother Oncol ; Wound repair in aging. A review. Methods Mol Med ; Structural and functional changes of normal aging skin. J Am Acad Dermatol ;15 4 Pt 1: Badwal RS, Bennett J. Nutritional considerations in the surgical patient. Dent Clin North Am ; Cartwright A.

Nutritional assessment as part of wound management. Nurs Times ; 98 Collins N. The difference between albumin and prealbumin. Adv Skin Wound Care ; Nutritional aspects of wound healing. Home Healthc Nurse Manag ; Scholl D, Langkamp-Henken B. Nutrient recommendations for wound healing. J Intraven Nurs ; 24 2: Granulation tissue formation in zinc-treated rats. Acta Chir Scand ; A dynamic regulator: J Wound Care ;10 4: J Infect Dis Toriumi DM. Insulinlike growth factor II correlates the rate of sciatic nerve regeneration in rats.

Braun-Falco M. Broussard CL. Ishii D. Faglia E. J Cutan Med Surg Lewin S. Fellinger EJ.

Hyperbaric oxygenation and wound healing. Glazner G. Rumalla VK. Lieberman JR. Marcus J. Smiell JM. Wright TE. Hyperbaric oxygen technology: Reinarz JA. Romeis JC. Diabetes Care Regional gene therapy with a BMPproducing murine stromal cell line induces heterotopic and orthotopic bone formation in rodents. Arch Head Neck Surg Kotler HS. Coulthard P. Soler PM. Xia YP. Shao Y. Utley D. Cells Tissues Organs Lohof A. Hoeller D. Wieman TJ. Yasko AW. Guckian JC. Mader JT.

Cheng E. Favales F. Nature Adjunctive systemic hyperbaric oxygen therapy in treatment of severe prevalently ischemic diabetic foot ulcer. Clinical evaluation of recombinant human platelet-derived growth factor for the treatment of lower extremity diabetic ulcers.

J Dent Educ Sefton MV. Lou J. Nature Rev Canc Laryngoscope Therapeutic use of hyperbaric oxygen for irradiated dental implant patients: Daluiski A. Eriksson E.

Hyperbaric oxygen therapy and the diabetic foot. Potentiation of developing neuromuscular synapses by the neu- Merkel K. Effects of keratinocyte growth factor-2 KGF-2 on wound healing in an ischemia-impaired rabbit ear model and on scar formation. Chen Z. Stevenson S. Woodhouse KA. Gene therapy: Therapy with hyperbaric oxygen for experimental osteomyelitis due to Staphylococcus aureus in rabbits.

J Wound Ostomy Continence Nurs J Orthop Res Counte MA. Lupien S. Microsurgery Diabetes Metab Res Rev Smith PD.

Contemporary oral and maxillofacial surgery, 5th edition

Neuroscience Le LQ. In vivo characterization of keratinocyte growth factor-2 as a potential wound healing agent. The effect of regional gene therapy with bone morphogenetic proteinproducing bone-marrow cells on the repair of segmental femoral defects in rats. A randomized study. Gene therapy concepts for promoting wound healing.

Radisky D. Petrie N. Enhancement of motor neuron regeneration by nerve growth factor. Miller J. Bissell MJ. Glass DL. Mandibular reconstruction with a recombinant bone-inducing factor: Yao F. Wound Repair Regen Brain derived neurotrophic factor and collagen tubulization enhance functional recovery after peripheral nerve transection and repair.

J Vasc Surg Poo M. Luxenberg DP. Wound Healing 15 J Pathol Hautarzt Esposito M. Bakker DJ. J Bone Joint Surg Arch Otolaryngol Head Neck Surg Jokstad A.

Aldeghi A. Worthington HV. The healing of segmental bone defects. Gene therapy in soft tissue reconstruction. Lane JM. Tissue engineering. Plast Reconstr Surg Borah GL. Putting tumors in context. Diabetic Ulcer Study Group.

Efficacy and safety of a topical gel formulation of recombinant human platelet-derived growth factorBB Becaplermin in patients with non healing diabetic ulcers: Guo S. A quick screen of health conditions may give additional data in the evaluation of the healthy patient.

Exercise capacity. In addition to this group of questions. Medication use is important. Most commonly oral-maxillofacial surgery is performed on healthy patients. Table Preoperative Patient Questionnaire 1.

MBA David N. This is especially true in patients with various organs on the brink of decompensation due to disease or comorbid conditions. Do you feel unwell? Have you ever had any serious illnesses in the past? Do you get any more short of breath on exertion than other people of your age?

Do you have any coughing? Do you have any wheezing? Do you have any chest discomfort on exertion? Do you have any ankle swelling? Have you taken any medicine or pills in the past 3 months including excess alchol?

Do you have any allergies? Have you had an anesthetic in the past 2 months? Have you or your relatives had any problems with a previous anesthetic?

What is the date of your last menstrual period? MD Oral-maxillofacial surgery frequently causes temporary but clinically significant alteration of the anatomy and physiology of the upper aerodigestive tract. This chapter presents the common medical situations that can compromise the successful outcome of oral or maxillofacial surgery. The liberal use of medical consultations is highly recommended for all situations in which a surgeon has concerns for the medical wellbeing of a surgical patient.

Emphasis is given to the means of detecting health problems preoperatively and preparing patients with various medical disorders so that complications in the perioperative period are avoided or minimized.

It is helpful to ask. A preoperative patient questionnaire has been used in determining whether any further risk should be ascertained.

History and physical examination if one of the above is abnormal. Preservation of cardiac health is an essential element of any perioperative protocol. Some herbal supplements are known to increase the risk of bleeding as well. In the discussion of the four conditions that follows. Serum creatinine concentration if undergoing major surgery. Cardiac output also depends on properly functioning valves.

Aspirin or other nonsteroidal anti-inflammatory drug use may exacerbate bleeding during major surgery. These conditions include coronary artery disease. Many of these tests are arbitrary and not supported by evidence-based research. This sets up an immediate clotting cascade resulting in thrombus formation. If guidelines at a particular center have been established.

Hematocrit for surgery with expected major blood loss 7. Coronary artery disease is one of the most studied diseases in humans. While most young and apparently healthy patients do not need any preoperative laboratory testing.

Glucose determination is helpful in those patients with diabetes or obesity. A blood count may reveal anemia or serve as a benchmark when excessive blood loss or anemia is found after surgery. Myocardial ischemia will occur when the supply of oxygen is inadequate to meet the demand for oxygen.

Over the past several years new paradigms regarding coronary artery disease have emerged and have been validated. Routine testing requirements may vary from operative center. Finally the load against which the ventricles must work should stay within reasonable limits to preserve optimal myocardial function.

Many plaques in the lumen of the coronary vessels are considered to be soft. The idea of a hard plaque slowly encircling the lumen of a coronary artery until occlusion has occurred has been replaced by the concept of plaque rupture. Electrocardiogram ECG recommendations as above. Coronary Artery Disease The two principal processes that cause an insufficient blood supply to the myocardium are coronary artery obstruction and spasm.

Pregnancy test for women who may be pregnant 6. Blood pressure and pulse for all patients 4. Laboratory testing may be helpful in a small subset of patients.

Several cardiac conditions can exist preoperatively that have the potential to www. A screening questionnaire for all patients see Table 2. There are no absolute cutoffs for age in estimation of risk.

Chest radiograph for patients over 60 years. This membrane may rupture even in small lesions. In the patient with a healthy heart and lungs.

The proper match of oxygen supply to oxygen use in myocardial tissue is the key to maintaining normal contractility and electrical activity. Principles of Medicine.

Myocardial oxygen need is increased when the heart has increased rate or mass. A history of exercise tolerance for all patients 3. Physical Examination The physical examination in patients with coronary artery disease is frequently unrevealing. The American College of Cardiology has produced a listing of major. A patient may give a history of dyspnea and chest tightness.

Additional risk factors such as elevated levels of homocysteine. High levels of LDL cholesterol. Anginal symptoms will dissipate soon after the provoking activity ceases or after transmucosal nitroglycerin is administered. There are no standard physical signs of coronary artery insufficiency so preoperative screening relies on historic information and electrocardiography.

A cardiovascular examination may show evidence of vascular or valvular disease. Patients with findings of peripheral vascular disease should be considered at high risk for underlying coronary artery disease. On heart examination an S4 may be present. In addition. Symptoms of compromised coronary or carotid arteries should be sought preoperatively in all adult males. It is important to ask patients suspected of having coronary artery disease if they have discomfort with exertion.

The patient may also experience dyspnea. It must be remembered that many patients with first time myocardial infarction have no known risk factors. Finally a thallium stress test can be used. Diminished or absent pulses. Medical Management of the Surgical Patient 19 and precipitating myocardial infarction or unstable angina.

C-reactive protein. A resting ECG should be done within a month of a planned elective general anesthetic and surgery in all males age 35 years and older.

The history is the most important determinant of risk.

Auscultation of the neck. Patients with a past history of cardiac disease should have preoperative posteroanterior and lateral chest radiographs to detect early signs of congestive heart failure. Patients may complain of a squeezing.

Typically these symptoms are reproducible. Infarction symptoms will usually persist despite nitroglycerin use or rest. All patients with a documented history of angina may have an increased risk of perioperative infarction.

Although it is unlikely to see resting ECG changes suggestive of acute ischemia. Surgery in such a situation should only proceed if required emergently. Angina that is worsening with respect to frequency. Myocardial ischemia produces decreased myocardial contractility rapidly leading to systemic hypotension and pulmonary vascular congestion. Specific questioning about problems occurring during physical activity or postprandially should be included. These risks are then entered www.

Several risk factors for coronary artery disease have been identified. This risk varies with the severity of the coronary disease and the degree of physiologic stress in the perioperative period. The limitation of flow leads to the symptom of angina. Patients who have angina symptoms that are progressive with less precipitating forces. Patients with stable angina have only a slightly raised risk during anesthesia and surgery compared to the normal population.

Patients with stable but poorly controlled angina need medical intervention to improve their cardiac status before most elective surgery. ST-T abnormalities Rhythm other than sinus eg. This zone is the area into which the myocardial infarction may extend and from which dysrhythmias can be generated. Although some studies indicate the risk of infarction increases with the duration of surgery. There is usually a need for increased cardiac output.

The cardiorespiratory system is no longer controlled by general anesthesia. It is a zone surrounding this infarcted tissue that is considered to be stunned or vulnerable. Patients who need nonurgent surgery in this 6-week window should be co-managed by a cardiologist.

A target-like zone is described in myocardial infarction. Heart Failure. To assist with these goals consideration should be given to radial artery cannulation for blood gas and pH measurement and precise blood pressure monitoring. Modern day general anesthesia may actually be protective of the myocardium. An immediate postoperative ECG should be obtained in patients with a history of coronary artery disease.

Adapted from Eagle KA et al. After the 6-week window has passed. The risk of general anesthesia after a recent myocardial infarction is due to possible extension of the earlier myocardial infarction and the development of cardiac dysrhythmias.

The presence of signs of chronic congestive failure following a myocardial infarction increases operative risk. Note that subsequent care may include cancellation or delay of surgery. No Yes Recurrent symptoms or signs?

Yes Recent coronary angiography or stress test? Steps are discussed in the text. Adapted from from Eagle KA et al. Typically the systolic blood pressure is lowered to between 90 and mm Hg unless significant hypertension was involved in the decompensation. Patients with severe heart failure may sleep in a sitting position or slumped against a countertop. Rarely isolated right-sided ventricular failure occurs. On lung examination rales may be present from pulmonary congestion and there may be dullness to percussion from pleural effusions.

Rarely a second diuretic such as metolazone would be added to boost the loop diuretic. Decompensation is manifested by increased symptoms of dyspnea on exertion or PND. Patients with PND may sit up on the side of the bed for a moment and then get up to drink a glass of water. Compliance refers to the ability of the heart to distend. Left ventricular dysfunction can be separated into systolic or diastolic dysfunction. In addition there may be global dysfunction due to more widespread ischemia.

In either case the management includes starting or increasing diuretic therapy. This is determined more by the severity of the heart failure than the urgency of the surgery. An echocardiogram may show evidence of diastolic dysfunction through measurements of compliance. Preload problems can occur from left heart failure causing fluid to back up into the pulmonary arterial tree. After appropriate diuretic therapy and ACE inhibition.

Preload is thought of as volume being presented to the right heart. Afterload reduction using vasodilators. Systolic dysfunction occurs after myocardial infarction or other direct muscle injury.

This reduces demand on the heart. Signs of infections or pulmonary problems should be pursued aggressively. The neck veins. As noted above it can be due to insults. In addition a diffuse PMI may be present. If a diuretic has not been prescribed. Left ventricular systolic dysfunction can be tolerated within the reserve capacity of the individual. Diagnostic testing for patients with heart failure includes an ECG.

On physical examination of the heart there may be an S3 gallop rhythm and the point of maximal impulse PMI may be shifted laterally and inferiorly. Diastolic dysfunction results from stiffness or reduced compliance of the left ventricle. Afterload reduction is a key tenet in the treatment of congestive heart failure.The history is the most important determinant of risk.

Some medical schools give exemptions for certain parts of the medical course to dentists who have MFDS. Lewin S. Glucose determination is helpful in those patients with diabetes or obesity. Congestive heart failure or myocardial ischemia can appear abruptly in susceptible patients going into AF. Jun Series: A chest radiograph will reveal an enlarged left atrium. Lower anterior dental extraction forceps Fig.