General Anaesthesia for Dental Procedures By: Dr. Mahmoud Al-mustafa Associate Professor Dept of Anaesthesia Faculty of Medicine – The University of Jordan 24 December 2013

Sensations Peripheral: Pain Temperature Touch deep light Proprioception Special senses Central: Awareness:  Apprehension; Fear and Anxiety

Anaesthesia In Surgery it implies : reversibly rendering the patient unconscious by drugs for the execution of a painful operative procedure - in a titrable and controlled way.

- Antidiuretic hormone Surgery Trauma  stress on the living body Metabolic Response to stress Neural Component  Autonomic system - Sympathetic - Parasympathetic Endocrine Component  Hormonal System - Growth Hormone - Cortisol - glucagon - Antidiuretic hormone - Renin – Aldosterone - etc ……

Anaesthesia Modulates the stress response by blocking the afferent limb of the response . Pain and awareness are blocked by anesthetic drugs , but other afferent limb factors are not ( e.g. Hypovolemia, hypoxemia, etc)  complete medical management of the patient – peri -operative Medical management

Anaesthesia Modern Anaesthesia is Composed of: Hypnosis: Inducing Controlled Loss of Awareness Analgesia: Inducing Controlled Loss of Pain (+/-) Muscle Relaxation( Controlled muscle Paralysis)

Hypnosis In Anaesthesia *Hypnosis: The state of being asleep Pharmacologically induced A non-physiological very deep level of sleep that deprives the patient from critical facullties. Can and should be titrated according to the level of surgical stimulus

Analgesia * State of freedom from pain Analgesia vs. anaesthesia: Analgesia can be brought about by local or regional techniques, or drugs with specific pain receptors action ( e.g. Opioids) without Loss of consciousness.

Muscle relaxation Paralyzing the patient’s muscles by use of drugs that block the acetylcholine receptors at the Neuromuscular junction Purposes: Facilitation of airway management Control of Ventilation Facilitation of Surgery Patient should be artificially ventilated !!

Stages of Anesthesia 2- Stage of uninhibited response (Excitement): 1- Stage of analgesia: Diminished pain perception, verbal contact maintained, laryngopharyngeal reflexes and voluntary control Present 2- Stage of uninhibited response (Excitement): Consciousness lost, verbal contact and voluntary control lost  uncontrolled, exaggerated, withdrawal type response to any stimulus Protective laryngopharyngeal reflexes maintained !

Stages of Anesthesia (continued) 3- Stage of Surgical Anaesthesia: Centers of the medulla become progressively depressed (vomiting, striated muscle tone, respiratory) Autonomic reflexes depressed It is the stage at which anaesthesia has depressed both the reticular activating system and perhaps selectively the pain synapses of the spinal cord and is the stage at which operations may be performed Divided into Four planes according to the depth of anaesthesia and marked by cessation of breathing at its lower end.

Stages of Anesthesia (continued) Stage 4: Stage of Respiratory Arrest * Cessation of Respiration = Cardiac Arrest * Anoxia * Direct Cardiac effects : e.g. arrhythmias * Danger of Death * Should not be reached by anaesthetist

Anesthesia in Dentistry 1- Local Anaesthesia 2- Sedation 3- General Anaesthesia

Dental Procedures Requiring Sedation or General Anesthesia 1- Oral Surgery: Removal of impacted teeth Multiple Dental extractions - Preprosthetic Surgery (Vestibuloplasties) Insertion of Osteointegrated plants Others….

Dental Procedures Requiring Sedation or General Anesthesia (CONTINUED) 2- Restorative Dentistry: Multiple dental restorative procedures (e.g. Rampant Caries) - Procedures performed on Mentally Retarded Patients

Dental Procedures Requiring Sedation or General Anesthesia (CONTINUED) 3-Temporomandibular Joint: Arthroscopy - Arthroplasty

Dental Procedures Requiring Sedation or General Anesthesia (CONTINUED) 4- Maxillofacial Surgery: - Trauma - Tumor - Reconstructive

Dental Procedures Requiring Sedation or General Anesthesia (CONTINUED) 5- Special patient Groups: Young Children esp. some with systemic Diseases (hemophilia,CHD) Mentally retarded Patients with poorly controlled Seizure activity - Those with an oral septic focus

Problems Related to Dental Anaesthesia 1- In / Outpatient selectivity 2- Competition for the Airway by both Dentist and Anaesthetist 3- Patients are often children 4- Mentally handicapped patients

Conduct of Anaesthesia 1- Pre-Operative Assessment 2- Intra-Operative Management 3- Post-Operative Management

Pre-Operative Assessment - History :medical,surgical,Anaesthetic,& Allergy - Medical Examination - Investigations: as per case - Informed Consent: signed by patient or guardian

Risk classification ASA I : A normal Healthy patient 0.06-0.08% ASA II : A patient with mild systemic disease 0.27-0.40% ASA III: A patient with severe systemic disease 1.8 - 4.3% ASA IV: A patient with severe systemic disease that is a constant threat to life 7.8 - 23% ASA V: Moribund patient who is not expected to survive without the operation 9.4-51% ASA VI: A declared brain dead patient whose organs are being removed for donor purposes “E” For Emergency surgery

Intra-Operative Management 1- Establishing Monitoring: Heart Rate, Blood Pressure, Electrocardiogram, Pulse Oxymetry, End Tidal CO2 Monitoring 2- Induction of Anesthesia : - Hypnosis => - Intravenous Drugs: (e.g. Sodium Thiopentone , Propofol, Etomidate, Ketamine ……) - Analgesia => - Nitrous Oxide gas - Opioid Drugs: Morphine, Pethidine, Fentanyl, Alfentanyl, Sufentanyl, Remifentanyl …. - Muscle Relaxation => - short Acting: Suxamethonium( used for rapid sequince induction) - Intermediate acting: Atracurium, Cis- atracurium, Vecuronium, Rocuronium, - Long Acting: d-tudocurarine, Pancuronium

Monitoring

End Tidal CO2 Value less than arterial CO2 3-5 mmHg

Intraoperative Management continued 3- Maintenance of Anaesthesia => - Intravenous drug infusion for short acting drugs - Inhalational Agents for Hypnosis: (e.g. Halthane,Sevoflurane,Isoflurane , Enflurane,desflorane, Nitrous Oxide, etc.. ) - Intermittent doses for intermediate or long acting muscle relaxants and analgesics

Intraoperative Management continued 4- Securing the Airway : * Using a Cuffed Endotracheal Tube - Orally - Nasally: Better surgical access * Throat pack * Meticulous Suctioning

Endotracheal Tube

laryngeal mask airway

Intraoperative Management continued 5- Securing Ventilation - Spontaneous Breathing - Manual ventilation - Using a mechanical Ventilator 6- Surgery Starts * Continuous Monitoring for - A,B,C - Adequate Anaesthesia -Necessary medical management

Intra-operative Issues Loose Teeth Surgical Debris Bleeding Secretions Use of Throat Pack Endocarditis Prophylaxis

Post–Operative Management 1- Emergence from Anesthesia * Patient in Left Lateral Position * Turn Anaesthetics off * Reversal of residual Muscle relaxation Anti-dote drug: e.g. Neostigmine * Extubation of the airways 2- Sending patient to Recovery Room 3- Recovery Room Nursing: Monitoring and Management 4- Assessment of Patient before Discharge By anaesthetist

Recovery Room Issues Recovery Room Issues: - Nursing in Lateral position - Management of complications : Pain, Nausea, Vomiting, Hypoxia, etc - Assessment by Anaesthetist before Discharge - prescribing oral analgesic drugs if patient is sent home - Advice NOT to Drive or operate machinery for 24 hours at least - making sure that there is somebody to escort patient home

Thank You