GENERAL PRICIPLES OF ANAESTHESIA FOR

MAXILLO FACIAL SURGERY

DR SUNIL MOKASHI

Senior ResidentDept of Anaesthesiology,

GOVT T D MEDICAL COLLEGE, Alleppy-688005, KERALA.

Introduction

History

Epidemiology

Embryology

Anatomy Of Facial Skeleton

Clinical effects of Maxillofacial trauma

Fracture Classification

Airway Problems in Maxillofacial Sx

Anaesthesia For Maxillofacial Surgery

. Preop Evaluation And Preparation

. Perioperative Management

INTRODUCTION

• Definition-

Maxillofacial and Oral surgery is speciality of dentistry

that includes diagnosis and surgical and adjunctive

treament of disease, injuries and defect ,including both

the functional and esthetic aspects of hard and soft tissues

of oral and maxillofacial region.

Maxillo Facial trauma

• Major concern for anaesthetists since Maxillofacial traumas

are usually associated with compromised airway.

• Surgery often carried out as emergency,full stomach.Bleeding

into upper airway passages is common

• AIRWAY CONTROL is first priority.

• Associated head trauma and cervical spine injuries should be

considered delicately while securing airway .

• Maxillo Facial trauma

• Accompanied by injury of upper

airway.

• Concomitant laryngotracheal injury -

may cause progressive dyspnoea in

unintubated patients in the absence of

airway obstruction from maxillofacial

injury.

Epidemiology• Injuries to orofacial soft tissues and facial skeleton commonly

result from sporting activities,accidents and intentional violence

Etiological causes of maxillofacial injuries across the world

Social factors:- Interpersonal violence increased and in many

countries m/c cause of orofacial injuries in urban areas often fuelled by alcohol

Climatic factors:- Arrival of snow and freezing weather during

winter, increased traffic volume,and interpersonal violence

during warmer months ,produce seasonal variation in

incidence of injuries

Road traffic accidents: Legislation and improved vehicular

design have decreased no of injuries in developed countries,

but in developing counties incidence of RTI increasing.

Statistics of Faciomaxillary injuries across world

Mandible is most commonly #red facial bone- 57% Mean age of patients with facial fractures- 24.4 yrs

Incidence of fractures is higher in males compared to females-81.3% Male to female ratio of facial #res greater in developing countries,i e

5.1:1.0 to 3.7 : 1.0 in developed countries.

Road traffic related faciomaxillary injuries are decreasing in developed countries and increasing in developing countries.

Body of mandible M/C mandibular #re site-27.2%. Assault related facial injuries had significantly increased in developed

countries and decreased in developing countries. Ref: Trends in pattern of facial fractures in different countries of world,Int. J.Morphol,30(2):745-756,2012.Dept

of Oral and Maxillofacial Surgery,oral medicine and periodontology,faculty of dentistry,University of Jordan.

• During the second world war, Maxillofacial surgery emerged as one of the major specialties, due to significant injuries from bomb blast and bullet injuries .That time there was a crisis of dental surgeons !

WORLD WAR II

HISTORY :

Hippocrates (460 BC)

The famous Greek physician Hippocrates, described

manually reducing dislocation of the mandible, indicating the

long history of this discipline .

HISTORY :The first general anaesthetic administered for a dental extractionis credited to Horace Wells. Wells, on 11th December 1844, underwent extraction of one of his own wisdom teeth by a colleague whilst under the influence of nitrous oxide.

In 1846, William Morton, a pupil of Wells, successfully demonstrated the propertiesof ether to facilitate dental extraction in Massachusetts

HORACE WELLS

William Morton

• CHALMERS J. LYONS (1874-1935)

He established principles of gentle surgery that advanced the

specialty and made extensive contributions to the oral surgery

literature.

• MATHEW H. CRYER (1840-1921)

He invented many instruments for the removal of teeth and other

surgical procedures In 1901 he established the first dental service

at the Philadelphia hospital.

• ROBERT H. IVY(1881-1974)

He was a great founder of oral surgery and plastic surgery.

“Ivy loop” for the treatment of jaw fractures

• JAMES EDMUND GARRETSON

• Father of oral surgery

• He is known as the father of oral surgery he established oral

surgery as a branch of medicine and dentistry though distinct

from both

• With his work a treatise on the diseases and surgery of mouth

jaws and associated parts first published in 1869, helped to

establish Oral & Maxillofacial surgery in U.S

• James Edmund Garretson  (1829-1895)  MB DDS was a

professor of Dental college in Philadelphia.

WALDEMAR WILHELM (1913-1992)

“Father Oral and Maxillo Facial Surgery “ honoured by

Columbian Association of Oral and MaxilloFacial Surgery.

Susruta’s knowledge from India to world

Sushrutha used skin flaps for repairing nose, procedure is

described in Sushruta Samhita. This procedure was observed

in India by a British Surgeon in 1793 and published in London

The Sushruta samhita was translated into Arabic and Persian

Ancient Father of plastic surgery and cosmetic surgery

Embriology of Facial bones Development

Begins week 4 centered around stomodeum, external depression

at oral membrane.

5 initial primordia from neural crest mesenchyme (week 4).

Single frontonasal prominence (FNP) - forms forehead, nose

dorsum and apex.

Nasal placodes develop later bilateral, pushed medially.

Paired maxillary prominences - form upper cheek and upper lip

Paired mandibular prominences - lower cheek, chin and lower lip

MAXILLO FACIAL SKELETAL ANATOMY

Divided into 3 segments

• Upper third - Frontal bone and cranium

• Middle third -nine bones- maxilla, zygoma, and bones that

comprise the orbital and nasal complexes.

• Lower third - mandible -made of six regions: symphysis, body,

ramus, condyle, coronoid process and temporomandibular

joint.

CLINICAL EFFECTS OF MAXILLOFACIAL TRAUMA

• Lacerations or fractures of facial skeleton- immediate or

delayed respiratory obstruction.

• Immediate obstruction may arise from

> Inhalation of tooth fragments

>accumulation of blood and secretions

>loss of control of tongue in unconcious /semiconcious

pt’s

• Pt’s with facial injuries should not be allowed to lie supine.

• They should be nursed in semiprone position with head

supported in bent arm

• Semiprone position> damaged teeth,blood and secretions,can

fall out of mouth and gravity pulls the toungue forward

• Pt shoud be manoeuvered into the semiprone recovery

position

• Neck should be held in neutral position.

• Protective collar is advisable until a fracture of cervical spine

has been excluded.

• An intracranial injury should be considered as possiblity

however minor injury to face.

• Initial haemorrhage after facial injury is common.

• Most likely cause of circulatory failure in facial injury is

accompanying skeletal fractures/ruptured viscus. These

should be actively managed in pt.

• Oedema feature of maxillofacial fracture >develop with in 60

to 90 min

• Initially patients may have good airway>gradual obstruction

can occur aft swelling of tongue and pharyngeal tissues.

• Resp compromise common on LEFORT lll fractures

(Mid face fractures)

LEFORT CLASSIFICATION OF FRACTURES OF FACIAL BONES

Rene LeFort in France reported maxillary fracture classification in

1901

• LeFort -I (transverse) –fracture line passes through nasal septum, maxillary antrum, pterygoid plates

• LeFort- II (pyramidal ) - fracture line passes through lacrimal bone, floor of orbit, upper part of maxillary sinus, pterygoid plates

• LeFort -III( craniofacial dysfunction) - complete separation of facial bone from cranial bone.

Fracture line passes through root of nose ,ethmoid, frontal suture, superior orbital fissure, lateral wall of orbit, fronto zygomatic & zygomatico temporal suture, upper part of pterygoid plates.

• Fracture mandible- most common in facial injuries• Dingman classification - most common site is condylar process(35%) - 2nd angle & body (20%) - symphysis (15%) - least common site –coronoid process

• Most common bone # in face is mandible (51%)

• Maxilla & zygoma are next common fracture (35%)

•Maxillo Facial fractures need special attention since it

associated with difficult airway and often airway will be

shared by surgeon.

MANDIBULAR FRACTURE

Unilateral mandibular fractures are stable.

Bilateral mandibular fractures are UNSTABLE -> The posterior

fragment may be pulled medially and upward and cause base of

the tongue to obstruct pharynx.

• Fracture zygoma - 2nd most common bone fracture in face - Also called Tripod fracture - fracture line passes through zygomatic frontal suture,orbital floor, infra orbital foramen, zygomatico temporal suture

• Tripod fracture( zygomaticomaxillary complex or malar fracture)

Maxillary sinus including the anterior and

postero-lateral walls and the floor of the orbit + zygomatic arch+ lateral orbital rim, usually including the lateral orbital wall, or the zygomaticofrontal suture.

This causes facial swelling and bruise Trismus + difficulty in opening mouth and

mastication

Maxillary fracture-CT

Zygomatico maxillary complex fractures

• Fractures of the NASAL bone

include swelling ,bruising,

• Difficulty in breathing

• Excessive nose

bleeding(aspiration in

unconcious pt’s)

• Nasal septal hematoma

obstructing nasal pathway.

Nasal bone & nasal septum - types 1. depressed fracture 2. angulated fracture

• Triage in severe maxillofacial fractures

1.Red (immediate) – need immediate medical attention.Patient with airway compromised,Hge,shock.

2.yellow(delayed) – medical attention with in 6 hr.Potentialy life threatening injury, but can wait until immediate casuality is stabilised

3.Green (minimal)- walking wounded 4.Blue (minor chance of survival)5.Black- dead on arrival/ no spontaneous breathing after clearing

the air way.

Sequence of evaluation

1. Overveiw

2.Primary survey

- Airway maintanance

-Breathing assisstance

-Circulation

-Disability

3.Resuscitation & secondary survey

4.Definite care- surgery/close monitoring in ICU

IMMEDIATE AIRWAY MANAGEMENT

• 1. Fully concious patients speaking coherently, has satisfied

ABC of ATLS -> wait for airway assessment

• 2. Unconcious patient but breathing -> wait for oximetry &

cautions airway & neurological assessment

• 3.Unconcious & apnoeic patient -> need emergency airway &

oximetry

• 4.An agitated & aggressive patients may be hypoxic

• Complications

• Airway compromise• Haemorrhage• Trismus• Cervical spine injury• Pneumoencephalus• Injury to oesophagus• Subcutaneous emphysema and pneumomediastinum

• Laryngeal injuries

• Head injury- intracranial haemorrahge

• Eye injury-simple corneal abrasion to open eye injury

• Abdomen injury- rupture of spleen,liver,intestine

COMPLICATIONS

1. AIRWAY COMPROMISE

Obstructed airway

Uncooperative and intoxicated patients

Full stomach

Disruption of normal anatomy

Maxillofacial trauma

Bleeding,edema,foreign body block airway anywhere

- Postero inferior displacement of # maxilla block

nasopharyngeal airway

B/l # of anterior mandible blocking oropharynx

soft tissue swelling & edema

In LeFort III fracture - facial bones displaced downward toward pharynx, mid-face instability contributes to soft-tissue airway obstruction.

Bilateral condylar fractures (“Andy Gump” fracture) with a symphyseal fracture or a bilateral body fracture of mandible- loss of support of glossal and suprahyoid musculature, allow soft tissues to fall posteriorly

Uncooperative or intoxicated patients, due to alcohol or drug

abuse, may contribute to difficulty in managing airway.

In upper airway injury oedema fluid can rapidly accumulate in

supraglottic and subglottic submucosa

2. Hypoxic brain injury or death from acute airway obstruction and hypoxemia -after complex maxillofacial and upper airway injuries

3. HAEMORRHAGE

• Bleeding from soft tissue lacerations, mouth and nose• Vascular injuries are common in penetrating neck trauma

Complications

4. Trismus

• Fractures involving condyles or impinging on

temporomandibular joint (TMJ) interfere with mechanical

opening of jaw.

• Injuries to mandible cause trismus due to muscle spasm and

pain on opening mouth.

• Once patient is sedated or anaesthetized, mouth can usually

be opened without much difficulty

5. Cervical spine injury

• All patients with maxillofacial and upper airway injuries should be considered to have cervical spine injuries unless proved otherwise

6.Cerebrospinal fluid rhinorrhea and otorrhea -when the base of the cranium is fractured.

7. Pneumocephalus -Fractures through posterior table of frontal sinus with dural tears and LeForte II and III fractures

Pneumocephalus is the presence of air or gas within the cranial cavity. It is usually associated with disruption of the skull: after head and facial trauma, tumors of the skull base, after neurosurgery or otorhinolaryngology, and rarely, spontaneously

8.Injury to oesophagus - severe laryngotracheal trauma can

produce oesophageal injuries.

9.Subcutaneous emphysema and pneumomediastinum - Air

from maxillary sinuses communicate with fascial planes of

neck and then with mediastinum

• Emergency management

• A patent airway should be immediately established

• If unconscious give chin lift or jaw thrust

• Fractured teeth, foreign bodies, and blood should be cleared

from oral cavity.

• Attempts to control bleeding including direct pressure, acute

reduction of fractures, and placement of nasal packs

• Nasopharyngeal bleeding controlled with nasal packing or a

balloon-tipped catheter placement

• Use airway adjuncts- oral & nasopharyngeal airways- displace tongue & soft tissue- patient can breath through or around them

• Significant maxillofacial injury with anatomic disruption or severe haemorrhage may require immediate airway protection with endotracheal intubation/tracheastomy

• Surgical repair

• Most patients with isolated maxillofacial injury donot require emergency surgery unless significant hemorrhage or airway compromise present

• Definitive care of should be rendered only after thorough multisystem evaluation, including airway examination, excessive blood loss and central nervous system (head and cervical spine) for injury.

MAXILLOFACIAL SURGICAL REPAIR

Intermaxillary fixation and rigid fixation are two methods of fixation, a

procedure for stabilizing broken bones and allowing them to grow together

in the proper position.

Fixation is an important step in treating fractures. It is also a crucial part

of orthognathic surgery, used to correct mandibular and maxillary

deformities.

Orthognathic surgery on the mandible and maxilla generally involves

breaking the bones in a controlled way and then resetting them into

correct positions. After the bone is set (a process called "reduction") a

period of fixation ensures proper healing.

MAXILLOFACIAL SURGICAL REPAIR

Oral and maxillofacial surgeons use two basic fixation techniques. One of

these, intermaxillary fixation, involves binding the jaw shut with wires or

elastic bands. The other, called rigid fixation, is a newer technique in which

tiny screws or plates are attached directly onto the fractured sections of the

jaw bone; it does not require physically binding the jaws shut.

• Pre Anaesthetic Evaluation

• Thorough airway evaluation

• Same as for any other major operation

• Patients can have swelling of face, missing or loose

teeth, pain and trismus limiting mouth opening or

a maxillo-mandibular fixation may be in situ.

• The nasal patency should be done to facilitate

nasal intubation.

• Complete evaluation including all lab

investigations, ECG, chest Xray, cervical spine

xray

• Pre Anaesthetic Evaluation

• Neurological evaluation in patients with co-existing head

injury

• Medical problems e.g. acute myocardial infarction, acute

alcohol intoxication and drug abuse.

• Cervical spine injury, intracranial injury, pneumothorax, flail

chest and abdominal trauma to be excluded.

• Relevant biochemical and radiological assay including blood

crossmatch essential.

Challenges faced during FACIOMAXILLARY FRACTURES.

• Difficult intubation due to anatomical disruption

• Sharing of airway between anaesthetist and surgeon

• Long procedure with significant blood loss

• Detailed discussion with surgeon regarding securing airway,

route of intubation, alternative methods of intubation

• .IMF preclude oral intubation ; so nasal intubation is choice

if nasal intubation not possible in

certain cases like basal skull # ,then tracheostomy has to be

done

• Difficult airway management in maxillofacial surgery

• Fiberoptic bronchoscope

• Bougie,

• ETT changer with jet ventilation capability,

• Sanders jet ventilator,

• Cricothyroidotomy kit ,

• Tracheostomy tray

• Retrograde intubation

• Retromolar intubation

• Submental intubation

• Supraglottic airway devices

• Difficult airaway management in maxillofacial surgery1. Airway management. Patients with complex maxillo-facial injuries are potential difficult airway patients. Difficult airway trolley should be checked and immediately

available.

2. Do not administer neuromuscular blocking agent until it is possible to do mask ventilation.

• Difficult airaway management in maxillofacial surgery. Maxillo-Mandibular Fixation - surgical reconstruction often

involves intraoperative maxillo-mandibular fixation to restore dental occlusion

• The fixation done with high tensile strength elastic bands (common) or classical wires

• Discuss with surgeon regarding removal prior to intubation and extubation

• Difficult airway management in maxillofacial surgery

. Throat pack to prevent aspiration of blood

A reinforced or flexo-metallic tube most commonly

Steroids perioperatively to reduce airway oedema.

Proper fixation of ETT-Displacement due to close proximity

to surgical field.

Different routes of tracheal intubation should be considerd.

Early tracheostomy/ cricothyroidotomy are definitive

procedures for securing airway.

• Awake intubation• Local anaesthesia of upper airway is essential for an awake

oral / nasal intubation.

• Nasal or oral mucosa may be anaesthetized with topical 2%

or 4% lidocaine. as nebulisation/topical sprays/gels

• Addition of adrenaline produces vasoconstriction, increases

size of nasal passage and decreases risk of local trauma

during nasotracheal intubation.

• The oral cavity, base of tongue and pharyngeal wall may be

anaesthetized with lidocaine

• Regional nerve blocks give upper airway anaesthesia.

• Oro-tracheal intubation

• Can be done under direct laryngoscopic view, fiberoptic

bronchoscope guided, by using lighted stylet, intubating LMA.

• Oro-tracheal intubation is not feasible if intraoperative

maxillo-mandibular fixation to be done.

• Naso-tracheal• It is the most common route of tracheal intubation.• It can be laryngoscope guided, fiberoptic bronchoscope guided

or blind. • Depending upon the clinical circumstances the patient may be

anaesthetized and breathing spontaneously or paralyzed, or may be awake.

• Nasal passage is well prepared with a vasoconstrictor and a topical anaesthetic

• Contraindications for Nasotracheal intubation

• Associated skull base fractures

• Cerebrospinal fluid rhinorrhoea

• Fractures of nasal skeleton and

• Anatomical obstruction of nasal airway (deviated nasal

septum,nasal spur, and hypertrophied nasal turbinates).

• These conditions cause physical obstruction to the passage of

nasotracheal tube.

• Presence of nasotracheal tube can interfere with surgical

reconstruction of naso-orbital - ethmoid (NOE) complex

• Preparation for a Nasal Intubation

• Applied with pledgets / cotton-tipped applicators soaked with

4% lignocaine.

• Gently inserted into each nostril & advanced until they reach

the posterior wall of the nasopharynx.

• Alternatively, solution can be dripped in using a 20 G IV

canula or sprayed using an atomizer.

• Both nares are prepared

• Safe dosage- 3 to 4mg/kgwt.

• Toxic plasma levels : > 5mcg /ml

• Nasal airways : well lubricated with lidocaine jelly.

ATOMIZER.

• Oral and Tracheal Anesthesia

• Lignocaine spray can be used

• pressurized bottles that deliver a metered spray of 10%

lignocaine.

• 4% soln of lidocaine sprayed in the mouth with an atomizer

• Remove the bulb and replace it with O2 tubing that is

connected to an O2 source.

• Provides a continuous spray.

• 2% lignocaine viscus can be used .

• Trans-oral trickle

• useful if transtracheal injection is not possible• fat neck, • neck abscess • neck deformity

• Fill a 10-cc syringe with 4% lidocaine & attach a 14-G plastic catheter.

• sitting position • Head tilted back • breath deeply through their mouth. • Hold the patient’s tongue with a gauze pad,• Slowly trickle lidocaine in 1–2 cc increments in the

back of the throat

• Trans-oral trickle

• coincide with inspiration. • Pause for a minute after the first 2 cc but continue to

hold the tongue to prevent swallowing.

• Nebulisation with local anaesthetic

• Nebulization of lidocaine 4% ( 3ml )via face mask or oral

nebulizer for 15–30 minutes can achieve highly effective

anaesthesia of the oral cavity and trachea for intubation.

• The major advantage of this technique lies in its simplicity and

lack of discomfort.

• In addition, very little working knowledge of the anatomy of

the region is required for its successful implementation

NEBULISATION WITH LOCAL ANAESTHETIC

Pharyngeal n.

Superior laryngeal n.

Internal laryngeal br.

External laryngeal br.

Inferior laryngeal br.

(recurrent laryngeal n.)

Vagus n.

Recurrent laryngeal n.

Cervical sympatheticganglionInferior ganglionof vagus n.

Anatomy and nerve supply of larynx

Vagus nerve supplies innervation to the mucosa ofthe airway from the level of the epiglottis to the distalairways, through both the superior and the recurrent laryngeal nerves

Most of the muscles of the larynx receive their innervation via the RECURRENT LARYNGEAL BRANCH of the vagus nerve this except cricothyroid (supplied by Ext Laryngeal Nerve)

Superior laryngeal nerve -sensation to the surfacesOf the epiglottis via Internal Laryngeal nerve and to the airway mucosa to the level ofthe vocal cords.

SLN continues as the External Laryngeal Nerve, it provides motor innervation to the cricothyroidMuscle.

The Recurrent Laryngeal Nerves – Sensoryinnervation the larynx and the trachea caudal to the vocalcords.

Superior laryngeal nerve block

• Hyoid bone is displaced toward the side being blocked. • One hand displaces the carotid artery laterally and

posteriorly.

• A 23 G - 25 mm needle is "walked off" the cornu (cartilage) of the hyoid bone in an anterior caudad direction, aiming in the direction of the thyroid ligament, until it can be passed through the ligament.

• At a depth of 1-2 cm, 2 ml of 2% lidocaine into the space between the thyrohyoid membrane & the pharyngeal mucosa.

• An additional 1 ml is injected as needle is withdrawn. • The block is repeated on the other side.

Superior laryngeal n. block-

• Internal approach for SLN

• SLN nerve can alsobe blocked by application of lignocaine

soaked pledgets held in the pyriform fossa with krause

forceps.

• RECURRENT LARYNGEAL NERVE BLOCK

• Sensory supply to b/w the carina and the VCs. • The right RLN originates at the level of the Rt. Subclavian A.,

and loops around the inominate A. on the right, & around the aortic arch on the Lt.

• sensory innervation to the VCs & trachea, motor innervation to the VCs.

• TRANSTRACHEAL or TRANSLARYNGEAL BLOCK

• For vagal branch- RLN

• Performed approx. One min prior to the start of the

bronchoscopy.

• Identifying the cricothyroid membrane).

• Hold the trachea.

• A 10 ml syringe containing 4% lidocaine is mounted on a 22-g,

35 mm plastic catheter over a needle, and is introduced into

the trachea.

• The catheter is advanced into the lumen, midline through the cricothyroid membrane, at an angle of 45 0, in a caudal direction.

• A loss of airway resistance & aspiration of air confirms placement,

• Needle is removed from the catheter.

• The patient is then asked to take a deep breath & then asked to exhale forcefully.

• At the end of the expiratory effort, 3-4 ml of 4% LA solution is rapidly injected .

• This will usually cause patient to first inhale to catch his or her breath and then forcefully cough, spreading the lidocaine over the trachea, making distal airway anesthetised.

• Local Nerve blocks Trigeminal nerve Sensory divisions • Ophthalmic division V1 • Maxillary division V2 • Mandibular division V3

3 major types of injections can be performed in the maxilla for pain control

• Local infiltration • Field block • Nerve block

Infiltration: • Involves injecting to tissue immediately around surgical site Field blocks: • Local anesthetic deposited near a larger terminal branch of a

nerve

Nerve blocks: • Local anesthetic deposited near main nerve trunk and is

usually distant from operative site

• Maxillary V2Posterior superior alveolar nerve block:• Used to anesthetize pulpal tissue, corresponding alveolar

bone, and buccal gingival tissue to maxillary 1st , 2nd , and 3rd molars

• Area of insertion - height of mucobuccal fold between 1st and 2nd molar

• Angle at 45° superiorly and medially• No resistance should be felt • Insert about 15-20mm• Aspirate and inject if negative

• Maxillary V2

Anterior superior alveolar nerve block:

• To anesthetize maxillary canine, lateral incisor, central

incisor, alveolus, and buccal gingiva

• Area of insertion is height of mucobuccal fold in area of lateral

incisor and canine

• Insert around 10-15mmMaxillary V2

• Mandibular V3

Inferior alveolar nerve block (IAN):

• Blocking the inferior alveolar nerve prior to entry into the

mandibular lingula on the medial aspect of the mandibular

ramus

• Area of insertion is the mucous membrane on the medial

border of the mandibular ramus at the intersection of a

horizontal line (height of injection) and vertical line

(anteroposterior plane)

• Height of injection - 6-10 mm above the occlusal table of the

mandibular teeth

• Glossopharyngeal N. (CN IX) Block

ANATOMY• Exits base of skull via jugular foramen • Travels w/ CN’s X, XI, and XII behind styloid process, along

side Int Carotid and Int Jugular vessels.• Motor: stylopharyngeus muscle, involved in deglutition.

• 3 Sensory Br.:– lingual branch: posterior third of the tongue, vallecula,

anterior surface of the epiglottis – pharyngeal branch:posterior & lateral walls of the pharynx – tonsillar branch: the tonsillar pillars.

Glossopharyngeal n. Block (intraoral)

Identify Post Tonsillar Pillar (Palatopharyngeal arch) lat pharynx

MAC 3 to help visualize.

22gu x 3.5” needle on 3-ring syringe adv submucousal

inject 2-3 ml of 1% lidoCaution: int jug and int carotid potential if too deep

GLOSSOPHARYNGEAL NERVE BLOCK is performed when topical techniques are not completely effective in obliterating the gag reflex.

This block can be performed after the mouth and oropharynx are adequately anesthetized. Branches of this nerve are most easily accessed as they transverse the palatoglossal folds .This is performed with the anesthetist standing contralateral to the side to be blocked and the patient s �mouth wide open.

The palatopharyngeal fold (posterior tonsillar pillar) is identified and a tongue blade, held with the non-dominant hand, is introduced into the mouth to displace the tongue medially (contralateral side) creating a gutter between the tongue and the teeth.

• A 25g spinal needle is inserted into the membrane near the floor of the mouth at the base of the posterior tonsillor pillor and advanced slightly (0.25-0.5 cm).

•An aspiration test is performed. If air is aspirated, the needle has passed through the membrane (through and through). If blood is aspirated, the needle is redirected more medially.

•Then, 2 ml of 1% Lidocaine can be injected into the posterior tonsillar pillar 0.5 cm lateral to the base of the tongue.

• This block has been reported as painful, and may result in a persistent hematoma.

•External approach for glossopharyngeal nerve block

Glossopharyngeal block (Peristyloid approach)Patient is placed supine and a line is drawn between the angle of the

mandible and the mastoid process.

Using deep pressure, the styloid process is palpated just posterior to the

angle of the jaw along this line, and a short, small-gauge needle is seated

against the styloid process.

The needle is then withdrawn slightly and directed posteriorly off the

styloid process.

As soon as bony contact is lost, 5–7 mL of local anesthetic solution are

injected after careful aspiration for blood.

•For both approaches, careful aspiration for blood must be

carried out prior to injection.

Prevents inadvertent intravascular injection. because the

glossopharyngeal nerve is closely associated with the internal

carotid a. & palatoglossal arch is highly vascular and even a very

small amount of local anesthetic can cause seizures.

Contraindicated in patients with coagulopathies or

anticoagulation

Different methods

1.Awake vs anaesthetized patient

2.Orotracheal / nasotracheal intubation

3.Direct /blind nasal intubation/ fiberoptic laryngoscopy

4.Anterograde /retrograde

5.Cricothyroidotomy, transtracheal jet ventilation, tracheostomy

• Retromolar intubation

• On arrival in O.T, after starting I.V infusion line, basic parameter likepulse rate, blood pressure and ECG should be recorded as basevalue. Patients should be premedicated with I.V glycopyrolate and midozalam.

• Oral intubation done after induction, after checking bilateral air entry,

• Hold thetube and move it laterally along the buccal sulcus beyond the lastmolar with fingers so that it rest in the retromolar space. In simplewords it is “repositioning” of the oral tube in the retromolar spaceso that it doesn’t interfere in dental occlusion. Tube is fixed at theangle of the mouth.

• Retromolar tube stabilized in position by fixation to first or second molar tooth in ‘figure of eight’ fashion.

• Allows intraoperative maxillo-mandibular fixation, restoring dental occlusion

• The adequacy of retromolar space determined by introducing

index finger in patient’s mouth and asking him/her to close

mouth.

• If no compression on finger- retromolar space adequate.

• Select one size smaller tracheal tube

Advantage: • Avoids need of any surgical technique like tracheostomy and

submentotracheal intubation

Disadvantages:• The tracheal tube can interfere with main surgical field and

positioning and application of dental fixation devices.• Too tight fixation of flexometallic tracheal tube with wire

ligature can deform tube.

• Submento-tracheal intubation• Orotracheal intubation with reinforced (flexometallic) endotracheal tube

done using standard technique.

• Under sterile painting and draping of chin and mouth, 2 ml of 2%xylocaine with adrenaline infiltration and a small 1.5 cm transverse skin crease incision should be made in the medial region of submental area, 2 cm behind the mental symphysis and adjacent to lower border of mandible.

• Blunt dissection through the subcutaneous fat, platysma, cervical fascia, and anterior bellies ofdiagastric, geniohyoid, and genioglossus muscles is made to create atunnel. The mouth opening should be maintained using mouth gag.The floor of the mouth exposed by retracting the tongue.

• Incision extended intraorally by blunt dissection with artery forceps through subcutaneous layers, mylohyoid muscle, submucosa and mucosa

• The intraoral opening is lateral to the submandibular and

sublingual ducts.

• A ‘submental tunnel’ created

• The tracheal tube briefly disconnected from breathing circuit

and tube connector removed

• The pilot balloon followed by tracheal tube is gently pulled

out through submental tunnel.

• Endotracheal tube stabilized intraorally manually or by

Maggil’s forceps

• Tube connector reattached and endotracheal tube connected

to breathing circuit.

• Chest should be auscultated for bilateral eual air entry

• Distance marking on endotracheal tube at submental skin exit

point noted.

• Usually 2 cm more than oral fixation.

• The tube fixed in position with sutures

Submento-tracheal intubation

Advantages • Provides secure airway,• Unobstructed intraoral surgical field, • Allows intraoperative maxillo-mandibular fixation • Avoids complications of tracheostomy Disadvantages• Can cause trauma to submandibular duct, sublingual gland or

duct and facial nerve or lingual nerve.• Superficial infection of the submental wound can occur - can

result in oro-cutaneous fistula

• Conscious sedation• Minimally depressed level of consciousness that retains the

patient’s ability to independently and continuously maintain an airway and respond appropriately to physical stimulation and verbal command.

• Effective method of facilitating treatment used in conjunction with appropriate local anaesthesia

• Technique 1 Oral administration of a single sedative drug (midazolam,

alprazolam, lorazepam,zolpidem, promethazine, chloral hydrate).

2. Nitrous oxide and oxygen (50%: 50%)3 Dexmedetomedine-

Loading- 1mcg/kg iv over 10 min.Maintainance- 0.2- 0.7mcg/kg/hr IV

4 Combination of oral sedative drugs or nitrous oxide and oxygen with an oral sedative drug

5. Parenteral administration of sedative drugs (intravenous-midazolam, propofol; intramuscular; subcutaneous; submucosal or intranasal-midazolam).

Blind nasotracheal intubation

• In patients with anticipitated difficult airway requiring awake intubation

and unable to open mouth (mechanical obstruction).

• Blind nasal intubaton is easier to describe than perform !!

• Pt may be intubated either awake or asleep,without visualising the larynx.

• Breath sound monitering is key for successful intubation, once the ETT

has passed into nasopharynx.

• At each inspiratory effort the tube should be advanced while monitoring

breath sounds.

• Successful tracheal intubation is confirmed by continued auscultation of

distant breath sounds, some resistance as the tube passes through vocal

cords,patient’s coughing, and capnography reading and waveform

Blind nasotracheal intubation

• If repeated insertions of ETT fail to enter trachea,the tube should be

withdrawn to the point ,where maximum loud breath sounds are heard

At this point 10 ml of air can be introduced into tube cuff(directs

the tube tip anteriorly away from post pharyngeal wall) & ETT can be

advanced further 2cm without loss of breath sounds.

The cuff is then deflated and tube shall be advanced into trachea.

Most commonly tube tends to enter oesophagus, extending pt’s neck

or providing cricoid pressure tends to align the tube with glottis and

increase th success rate of intubation.

Blind nasotracheal intubation

Contraindications

Basal skull fractures with/without CSF rhinorrhoea.

Bleeding diasthesis

Upper aiway foreign body

Large bilateral nasal polyps

Abscesses and severe laryngealtrauma

Complications

Nasopharyngeal haemorrhage

Laryngeal trauma

Retropharyngeal perforation

Paranasal sinusitis

• Involves minimum movement of cervical spine• Safest way in suspected cervical spine injuries• Bleeding in upper airway makes visualization of larynx difficult

Fibreoptic intubation

• Procedure

• Topical anesthesia of larynx and trachea may be achieved

by transtracheal injection or a “spray as you go”

(SAYGO) technique.

• SAYGO -intermittent application technique that causes

coughing and requires time for recovery after each

application.

• Use of an epidural catheter within the working channel of

fiberscope - effective means of administering SAYGO.

•  Tracheal tube mounted   on flexible fiberoptic

laryngoscope for the nasal or oral route   

• Patient position: supine, semisitting, or sitting

• Rapport: full explanation   

• Insertion cord kept straight and scope maneuvered in

three planes   

• Tip flexion-extension, rotation, and advance-

withdrawal   

• Secretions aspirated   

Targets (epiglottis, vocal cords, tracheal

cartilages, carina) kept in center of view as it is

advanced  

Advance close to carina

Tracheal tube passed over flexible fiberoptic

laryngoscope   

Tube position confirmed and secured and

anesthesia induced

RETROGRADE INTUBATION

Useful in TM joint ankylosis as an alternative to nasal intubation

Cricothyroid membrane is punctured with needle inserted horizontally (so that the vocal cords are not damaged) with bevel directed cephalad.

The intratracheal position of needle confirmed by aspiration of air

A guide wire passed through it upward through vocal cord into pharynx & mouthJaw thrust and tongue traction facilitate passage of guide behind tongue

ETT is passed through guide wire Only after crossing vocal cord by ETT guide wire removed Further advancement of ETT into trachea

COMPLICATIONS

Bleeding

Subcutaneous emphysema

Pneumomediastinum

Pneumothorax

Rescue airway devices

Use Supraglottic device – LMA ,Combitube, laryngeal tube,

COMBI TUBE

COMBI TUBE

CRICOTHYROTOMY

Creates a percutaneous airway through cricothyroid membrane. Cricothyrotomy can be performed with a surgical blade(surgical) or cannula (needle) techniqueFacilitates rapid restoration of ventilation and oxygenation in the “cannot intubate, cannot ventilate” situation

Needle cricothyrotomy

Equipment - Kink-resistant cannula  ,  High-pressure ventilation system,Technique Insert cannula through cricothyroid membrane    Confirm tracheal position by aspiration of air with 20-mL syringe    Maintain position of cannula Attach ventilation system to cannula   Ensure an open upper airway    Commence cautious ventilation    Confirm inflation and deflation of lungs   Convert to a surgical cricothyroidotomy if ventilation fails or any complications develop

Surgical cricothyrotomyEquipments - No. 20 scalpel  ,  Cuffed tracheal or tracheostomy tube with 6- or 7-mm internal diameterTechnique 1: Extend head and neck and identify and immobilize the cricothyroid membrane

2: Horizontal stab incision through skin and cricothyroid membrane. Leave blade in place until the tracheal hook is in position

3: Caudal and outward traction on cricoid cartilage with the tracheal hook, remove scalpel   

4: Insert tube and inflate cuff    5: Ventilate with a low-pressure source    6: Confirm pulmonary ventilation

Percutaneous transtracheal ventilation -

Percutaneous transtracheal ventilation (PTV) involves oxygenation and ventilation via a needle or surgical cricothyroidotomy using an improvised ventilation device.

Confusingly, although this is a form of conventional ventilation, it is sometimes referring to as "jet ventilation" when a high pressure source is used to deliver oxygen.

However, low pressure systems .eg, self-inflating bag connected to the cricothyroidotomy catheter via a 3.0 mm internal diameter endotracheal tube adapter, 7.0 mm ID ETT adapter connected through a 3 cc syringe, are sufficient in most patients if a high flow oxygen system is not available

TRANSTRACHEAL JET VENTILATION

Transtracheal jet ventilation refers to high frequency, low

tidal volume ventilation provided via a laryngeal catheter by

specialized ventilators that are usually only available in the

operating room or intensive care unit.

•When experienced surgeon not immediately available and

the anaesthesiologist is inexperienced in procuring a surgical

airway technique, then TTJV can be a life-saving alternative

By placing percutaneous transtracheal catheters

TRANSTRACHEAL JET VENTILATION

Begin regular ventilation by intermittently opening and closing

the in-line valve (figure 6); by intermittently occluding the side

port, y-connector, or stopcock (figure 4 and figure 5); or by

ventilations with the self-inflating resuscitation bag, depending

on the system in use.

.

Use I:E ratio of 1:4 to 1:5, with a breath rate of 10 to 12/min for

most children.

Change the ratio to 1:2 to 1:3 with a breath rate of 15 to 20/min

in the setting of increased intracranial pressure to improve CO2

elimination.

With partial or complete upper airway obstruction, use the ratio

of 1:8 to 1:10 with a breath rate of 5 to 6/min to reduce the risk

of pulmonary barotrauma. Adjust these ratios based on clinical

monitoring, blood gas measurements, and chest radiography

PTV may be used successfully in partial laryngeal obstruction as

the "ball-valve" effect, while constraining natural inspiration,

adequately permits exhalation

Ventilatory methods should use a longer expiratory time (eg, I:E

ratio of 1:8 to 1:10), lower oxygen delivery pressure and flow

rate, and as large a catheter as possible. In addition, the clinician

should carefully monitor for chest rise and fall with inspiration

and expiration

High pressure oxygen source — One of the following oxygen

sources is recommended:

Hospital wall outlet without a regulator or set at the maximum

flow rate of 15 L/min which provides oxygen at 58 psi (400 kPa, 4

atmospheres) for adolescents and adults; for younger children

use a maximum flow rate of 10 to 12 L/min which provides

oxygen at 25 to 35 psi (172 to 241 kPa, 1.7 to 2.4 atmospheres)

Trans tracheal ventilation for needle cricothyroidotomy

TRACHEOSTOMY

Requires incision of skin and subcutaneous tissues,

separation of strap muscles, division of isthmus of

thyroid gland, incision of anterior wall of trachea,

and insertion of cuffed tracheotomy tube.

If the airway is unobstructed and patient can

breathe adequately, intubation after induction of

GA preferred

Preoxygenation along with aspiration prophylaxis

with metoclopramide, glycopyrrolate and ranitidine

Induction of general anaesthesia using a potent

volatile agent and spontaneous ventilation is

generally considered to be the safest technique

Thiopentone or propofol may be necessary if the

patient is confused or uncooperative

Rapid sequence induction

INTUBATION IN UNOBSTRUCTED AIRWAY

Orotracheal intubation with south polar preformed tracheal

tube is usually the technique of choice with isolated midface

fractures .

Nasotracheal route in is commonly employed in patients

undergoing maxillofacial surgery.

Intubation with north polar preformed tracheal tubes for

mandibular fractures allows intermaxillary fixation and

assessment of dental occlusion.

FLEXO METALLIC ET TUBE

The use of neuromuscular blocking agents should generally be

avoided until airway is secured.

Positive pressure ventilation by mask may become impossible in

severe facial trauma and may worsen subcutaneous emphysema

requiring immediate tracheostomy.

ANAESTHETIC PRICIPLES

• Monitors : Pulse oximeter, NIBP/ IBP, ECG, SpO2,

EtCO2.

• IVL: - Secure peripheral lines with widebore

cannulas. Central line can be secured for monitering

JVP/fluids.

• Premedications:

• Benzodiazipine like midazolam,

Antisialagogues – Glycopyrrolate,

Anti emetic- Ondansetron/ metaclopramide.

H2 blockers/proton pump inhibitors-

Ranitidine,omeprazole,pantoprazole

• Preoxygenation – by 100% oxgen• Full stomach/unprepared pt’s- rapid sequence

intubation• I/v induction agent agents should be used with caution in

patients with airway compromise. Propofol /TPS.

uses –reduce agitation,smooth induction.

- I/V midazolam for agitated patients

- ketamine is not useful in patients with concomitant

intracranial & ocular trauma

- In hypovolemic patients I/V agents administered in

small bolus doses.

Inhalational agents - Potent,safe & widely used sevoflurane is prefered decreased effect CBF autoregulation and ICT. isoflurane and desflurane halothane can b used

Reduction in CMRo2 & metabolic rate is more with

isoflurane ,enflurane than halothane.

Muscle relaxant - Succinyl choline ( avoided in patients with hyperkalemia,raised IOT, k/c/o malignant hyperthermia)

Fentanyl ,sufentanyl,alfentanyl may be given

intraoperatively for analgesia & prior

to inducing agents to supress pressor

responses

Large dose is avoided

After securing endotracheal tube muscle relaxant- vecuronium /atracurium/rocuronium

Maintain with inhalational agents

N2O is best avoided( in midface fracture & in penetrating eye injury, pneumocephalus)Opiods –fentanyl,sufentanyl or alfentanyl can be used

INTRAOPERATIVE MANAGEMENT

Most patients with maxillofacial # doesn’t require emergency

surgery unless significant haemorrhagege ,airway compromise

present

Most techniques of induction & maintanance of aneasthesia are acceptable as long as airway is secured

N2o is best avoided( in midface # & in penetrating eye injury)

I/V fluids – should be titrated to have adequately hydrated patients with stable vital signs & urine out put of 1ml/kg/hrPatients having adequate airway - Induction with Thiopentone, propofol,Etomidate - Muscle relaxant –Succinyl choline atracurium/ vecuronium/

Indication for post operative ventillation

- considerable edema of airway.

- lengthy surgical procedures & extensive manipulation.

Use narcotic / Bzd if post operative ventillation is needed.

Post operative care

- Antiemetics in patients with Inter Maxillary Fixation (IMF)

- If IMF in place ,wire cutter must be available next to patient

- Post operative pain is releived by NSAIDS & Narcotics

- Maintance of airway with nasopharyngeal airway

EXTUBATION

Carried out when patient is fully conscious & with intact airway reflexesIndication for post operative ventilation - considerable edema of airway - lengthy surgical procedures & extensive manipulation

Orthognathic surgery

Maxilla, mandible, or both are sectioned into pieces and are reassembled with plates or wires to improve facial appearance and dental occlusionPatients undergoing these operations are young adults , most are ASA I.

Due to increased chance of bleeding- hypotensive anaesthesia sometimes employed-usually with beta blockers labetolol /esmolol in combination with isoflurane