Anesthesia for Otorhinolaryngologic Surgery PDF

ANESTHESIA FOR OTORHINOLARYNGOLOGIC SURGERY Ear / oto.. Nose/ rhino.. Throat/ laryngo.. Anesthesia for ENT surgery Dr.Musab Abdallah Objectives Endoscopic surgeries Ear Surgery Nasal and Sinus Surgeries Uses of laser and its safety...

ANESTHESIA FOR OTORHINOLARYNGOLOGIC SURGERY Ear / oto.. Nose/ rhino.. Throat/ laryngo.. Anesthesia for ENT surgery Dr.Musab Abdallah Objectives Endoscopic surgeries Ear Surgery Nasal and Sinus Surgeries Uses of laser and its safety Head and Neck Cancer Surgery Maxillofacial Reconstruction and Orthognathic Surgery Tonsillectomy and bleeding tonsils  Endoscopic surgeries (Laryngoscopy, Microlaryngoscopy, Esophagoscopy and Bronchoscopy) Preoperative evaluation should focus on airway assessment, particularly given that operative indications, which may include: foreign body aspiration, foreign body esophagus, vocal cord dysfunction, tracheal stenosis, obstructing tumors. Intraoperative anesthetic management usually requires muscle relaxation, careful planning of oxygenation and ventilation, and specific strategies for cardiovascular stability.  Muscle relaxation frequently needs to be profound. Oxygenation and ventilation can be achieved by placement of a smaller endotracheal tube (ETT) with conventional positive-pressure ventilation. Cardiovascular stability is challenging with varying surgical stimulation.  Ear Surgery (Stapedectomy, Tympanoplasty, Mastoidectomy, and Myringotomy) Intraoperative management concerns include avoidance or cautious use of nitrous oxide Hemostasis is critical in microsurgery facilitated by : Head-up position, Topical or infiltrated epinephrine, Mild controlled hypotension.  postoperative nausea and vomiting (PONV) prophylaxis.(use of dexamethasone, ondansetron, and propofol for induction and maintenance)  Laser Safety: Laser light differs from ordinary light, it offer the surgeon excellent precision and hemostasis but create safety concerns as well For operating room staff:Toxic fumes and eye injury. The greatest danger with laser airway surgery is endotracheal tube (ETT) fire. Following precautions should be observed: Inspired oxygen concentration should be low. Nitrous oxide should be avoided. The ETT cuffs filled with saline. A well-sealed cuffed tube will minimize oxygen concentration in the pharynx. Laser intensity and duration should be limited as much as possible. Saline-soaked pledgets should be placed in the airway to limit risk of ETT ignition. A source of water (e.g., 60-mL syringe) should be immediately available in case of fire. Nasal and Sinus Surgery (Polypectomy, Endoscopic Sinus Surgery, Rhinoplasty, Septoplasty and Maxillary Sinusotomy) Preoperative considerations include difficult mask ventilation, liability to bleeding. Local anesthesia: soaked gauze, can be with epinephrine or any vasoconstricter but can cause hypertension and tachycardia.  FESS (functional Endoscopic Sinus Surgery)  General anesthesia: attention to endotracheal tube, Eye protection and adequate Neuromuscular block. Hypotension anesthesia is a good choice. Extubation and emergence: priorities include decreasing coughing and gagging. Head and Neck Cancer Surgery (Laryngectomy, Glossectomy, Pharyngectomy, Parotidectomy, Hemimandibularectomy, and Radical Neck Dissection) Preoperative considerations: heavy tobacco and alcohol use. altered airway anatomy ( pathology it self or the effects of treatment such as radiation therapy). So consideration of awake intubation, fiberoptic intubation, induction with spontaneous ventilation, and preoperative tracheostomy may be crucial. Intraoperative monitoring: Invasive monitoring is advised if possible. Multiple Intravenous lines. Closely monitoring of temperatur. Intraoperative tracheostomy may be required. Neuromuscular blockade may interfere with nerve identification and monitoring.  Checking the facial nerve function is important consideration during resection of acoustic neuromas or glomus tumors. Neuromuscular blocking agents better to be avoided in these cases. Maxillofacial Reconstruction and Orthognathic Surgery (LeFort Fracture Correction, Developmental Malformation Correction, Radical Cancer Surgeries, and Obstructive Sleep Apnea Treatment)
Preoperative considerations: pathology and abnormal anatomy can lead to mask ventilation and intubation difficulty. So, fiberoptic intubation of the nose or mouth, or preoperative tracheostomy should be considered. Avoid Nasal intubation in case of coexisting basal skull fracture (LeFort II or III fracture)  ETT kinking or circuit disconnect is more likely because of the proximity of the airway to the surgical field, necessitating careful monitoring of end tidal CO2 and peak airway pressure throughout. Evaluation of the airway before extubation : (bleeding, edema or throat pack) ANAESTHESIA FOR TONSILLECTOMY lymphoid tissue The tonsils are 3 separate pieces of tissue: the lingual, the pharyngeal (adenoid) and the palatine tonsils. Rich in blood supply and veninous drainage, close to large vessels. Indications for surgery The absolute indications for surgery are: Upper airway obstruction, peritonsillar abscess, recurrent tonsillitis with associated febrile convulsions and to take biopsy. Contraindications for surgery are Bleeding diathesis. Acute infection. Anaemia. Significant anaesthetic risk. Pre-operative assessment Check for acute infection, heart murmur and obstructive sleep apnoea. obstructive sleep apnoea: adenotonsillar hypertrophy is the most common cause. symptoms may be: Nocturnal (snoring, short apnoeic episodes, grunting and restlessness). Daytime (headaches, feeling tired in the morning and excessive daytime sleeping)  The signs include chronic hypoxaemia (polycythaemia and right ventricular strain) Intra-operative management The endotracheal tube: preferably armored or reinforced tube because of shared airway and surgical instruments (Boyle-Davis gag) and high possibility of kinking or dislodging. Post-surgery and the emergence from anaesthesia: Careful suction (under direct vision to limits the damage to the tonsillar bed). Ensure adequate spontaneous breathing before extubation. Extubate in left lateral position. Post-operative management  Administer oxygen until fully recovered.  Post-operative analgesia.  Observation for evidence of post-operative bleeding.  Routine observations of pulse, blood pressure, respiratory rate and pain. Complications Pain Nausea and vomiting Bleeding Post-tonsillectomy bleeding This is a serious complication, which can present in recovery or occur after hours later. Remember that: The volume of blood loss cannot be measured and the patient may be hypovolaemic and need fluid resuscitation before induction. Assessing the following may help:  Conscious level/Glasgow coma score  Capillary refill time  Pulse rate  Urinary output The stomach might be full of swallowed blood (risk of aspiration) Difficult intubation due to airway edema.  A rapid sequence induction Use a wide bore naso/oro-gastric tube to empty the stomach. Extubate awake in left lateral position. Post-operative haemoglobin and coagulation screen must be checke. Close monitoring in HDU or ICU.