Anaesthesia for endoscopic surgery

Anaesthesia for endoscopic airway surgery involves unique challenges. The anaesthetist and surgeon are working in close anatomical proximity and the concept of shared airway is never more relevant. Understanding the planned procedure and the needs of the surgeon for access to the surgical field will enable the provision of anaesthesia and airway management using a variety of techniques. Planning for safe induction, maintenance and emergence of anaesthesia will also be guided by the specific pathology and patient characteristics and requires effective communication between the surgeon and anaesthetist.     

Anaesthesia for endoscopic surgery

Anaesthesia for endoscopic ear, nose and throat surgery involves unique challenges. The anaesthetist and surgeon must work in close anatomical proximity, and the concept of the ‘shared airway’ is never more relevant. The anaesthetist requires a thorough understanding of the planned procedure and the specific requirements of the surgery in order to maximize accessibility to the surgical field whilst also providing safe airway management and maintenance of anaesthesia using a variety of specialist techniques. Planning for safe induction, maintenance and emergence from anaesthesia is guided by the underlying pathology and individual patient characteristics, and requires effective communication between the multidisciplinary team.     

Anaesthesia for endoscopic surgery

Shared airway procedures are unique in that both anaesthetist and surgeon are working in the same anatomical field. Close cooperation between anaesthetist and surgeon, an understanding of each other’s problems and knowledge of specialist equipment are often required. There is no ideal anaesthetic technique for all endoscopy procedures and the technique chosen depends on the patient’s general condition, the size, mobility and location of the lesion, the use of a laser, and surgical requirements. Smooth emergence and recovery from anaesthesia are essential.     

Low-flow apnoeic oxygenation for laryngeal surgery: a prospective observational study

Laryngeal surgery requires a shared airway and close collaboration between surgeon and anaesthetist in order to optimise operating conditions. Apnoeic oxygenation uses the principle of aventilatory mass flow to maintain oxygenation of pulmonary capillary blood under apnoeic conditions while minimising laryngeal movement. Concerns regarding accumulation of carbon dioxide and resultant acidaemia have limited the use of the technique. We performed a prospective study of low-flow apnoeic oxygenation for patients undergoing microlaryngoscopy under general anaesthesia in order to evaluate the ability of the technique to maintain oxygenation and determine the resultant rate of carbon dioxide accumulation. Sixty-four patients undergoing microlaryngoscopy under general anaesthesia were studied between November 2016 and December 2018. Intra-operative oxygenation was provided via a 10-French oxygen catheter placed into the trachea delivering oxygen at 0.5–1.0 l.min⁻¹. Data regarding apnoea time, peripheral oxygen saturation and venous blood gas concentrations were recorded. The mean (SD) duration of apnoea was 18.7 (7.2) min. Apnoeic oxygenation allowed successful completion of the surgical procedure in 62/64 patients. Mean (SD) rate of rise of the venous partial pressure of carbon dioxide was 0.15 (0.10) kPa.min⁻¹. Operating conditions were recorded qualitatively as being adequate in all cases. No adverse effects were reported. Low-flow intra-tracheal apnoeic oxygenation is a simple, effective and inexpensive technique to maintain oxygenation for laryngeal surgery.     

Airway management and anesthesia in neonates, infants and children during endolaryngotracheal surgery

BACKGROUND: Endolaryngotracheal surgery in neonates, infants and children poses a big challenge for both anesthesiologist and surgeon. The narrowness of the airways and the great variability of the pathological lesions necessitate close collaboration between the surgical and the anesthesia team to provide optimal operating conditions and ensure adequate ventilation and oxygenation. METHODS: Sixty-two anesthetic records of endolaryngotracheal surgical procedures in neonates, infants and children with ASA physical status 1-3 were analyzed retrospectively. Anesthesia was administered as total intravenous anesthesia; propofol supplemented with remifentanil. Ventilation was performed as supraglottic, superimposed high-frequency jet ventilation via jet laryngoscope with integrated jet nozzles. RESULTS: Age was 58.93 (SD 35.40) months, range 3 weeks to 14 years; body weight 17.83 (SD 8.79) kg, range 2.4-50 kg. The capillary pCO(2) 5 min after the start of the surgical procedure (n = 62) was 40.01 (SD 7.71) mmHg and after 20 min (n = 24) 41.77 (SD 7.12) mmHg. No hypoxemia (oxygen saturation <90%) developed. All patients were hemodynamically stable during jet ventilation. Barotrauma or gas insufflation in the stomach did not occur. No perioperative tracheostomy was necessary. Laryngospasm occurred in one child during emergence from anesthesia. Four infants received postoperative conventional respirator therapy in the ICU overnight. CONCLUSIONS: Supraglottic superimposed high-/low-frequency jet ventilation via jet laryngoscopes with integrated jet nozzles is a minimally invasive ventilation technique for neonates, infants and children in endolaryngotracheal surgery, which allows an unimpaired operating field for the surgeon especially in LASER surgery.     

Transtracheal high frequency jet ventilation for endoscopic airway surgery: a multicentre study

Serious complications during high frequency jet ventilation(HFJV) are rare and have been documented in animals and in casereports or short series of patients with a difficult airway.We report complications of transtracheal HFFJV in a prospectivemulticentre study of 643 patients having laryngoscopy or laryngeallaser surgery. A transtracheal catheter could not be insertedin two patients (0.3%). Subcutaneous emphysema (8.4%) was morefrequent after multiple tracheal punctures. There were sevenpneumothoraces (1%), two after laser damage to the injector,one after difficult laryngoscopy, four with no clear cause.Arterial desaturation of oxygen was more frequent during lasersurgery and in overweight patients. Transtracheal ventilationfrom a ventilator with an automatic cut-off device is a reliablemethod for experienced users. Control of airway pressure doesnot prevent a low frequency of pneumothorax. Br J Anaesth 2001; 87: 870–5     

Anaesthesia for endoscopic surgery

Anaesthesia for endoscopic procedures of the supraglottis, glottis and subglottis requires close cooperation between the anaesthetist and surgeon. The preoperative assessment of the patient is discussed and the different types of vocal cord pathology described and illustrated. Anaesthetic techniques for endoscopy are explained and the advantages and disadvantages of closed and open systems are compared. Jet ventilation techniques are also described.     

Anaesthesia for endoscopic surgery

Shared airway procedures are unique in that both anaesthetist and surgeon are working in the same anatomical field. Close cooperation between anaesthetist and surgeon, an understanding of each other’s problems and knowledge of specialist equipment are often required. There is no ideal anaesthetic technique for all endoscopy procedures and the technique chosen depends on the patient’s general condition, the size, the mobility and location of the lesion, the use of a laser, and surgical requirements. Smooth emergence and recovery from anaesthesia are essential.     

Anaesthesia for endoscopic sinus surgery

Endoscopic sinus surgery is commonly performed and has a low risk of major complications. Intraoperative bleeding impairs surgical conditions and increases the risk of complications. Remifentanil appears to produce better surgical conditions than other opioid analgesics, and total intravenous anaesthesia with propofol may provide superior conditions to a volatile‐based technique. Moderate hypotension with intraoperative β blockade is associated with better operating conditions than when vasodilating agents are used. Tight control of CO₂ does not affect the surgical view. The use of a laryngeal mask may be associated with improved surgical conditions and a smoother emergence. It provides airway protection equivalent to that provided by an endotracheal tube in well‐selected patients, but offers less protection from gastric regurgitation. Post‐operatively, multimodal oral analgesia provides good pain relief, while long‐acting local anaesthetics have been shown not to improve analgesia.     

Anaesthesia for carinal resection

A case of adenocystic carcinoma (cylindroma) of the trachea is reported. Ventilation was successfully maintained for long periods by use of the venturi technique during resection of the carina, and during a later operation for relief of tracheal stenosis.     

Anaesthesia for thoracic surgery

Thoracic anaesthesia is an expanding and evolving sub-speciality. This article will focus primarily on the anaesthetic management of major lung resections, procedures which are generally performed for malignant disease and which can confer significant mortality and morbidity. The equipment needed and ventilatory strategies during one-lung anaesthesia will be discussed and the important changes in respiratory physiology that occur will be looked at in detail. Recent advances in pain management necessitate that postoperative analgesic regimens are covered in some depth. There has been an increase in the number of video-assisted thoracoscopic surgery (VATS) cases, and the merits and anaesthetic implications of VATS procedures are reviewed.     

Superimposed high-frequency jet ventilation (SHFJV) for endoscopic laryngotracheal surgery in more than 1500 patients

Background. Superimposed high-frequency jet ventilation (SHFJV),which does not require any tracheal tubes or catheters, wasdeveloped specifically for use in laryngotracheal surgery. SHFJVuses two jet streams with different frequencies simultaneouslyand is applied in the supraglottic space using a jet laryngoscopeand jet ventilator. Methods. Between 1990 and 2004, SHFJV was studied in 1515 consecutivepatients (including 158 children requiring laryngotracheal surgery)prospectively. Ventilation was performed with an air/oxygenmixture and anaesthesia was administered i.v. Results. Adequate oxygenation and ventilation was achieved in1512 patients. Arterial blood gas analyses (BGA) were performedbetween 1990 and 1994; thereafter BGA was only performed inpatients with high-grade stenosis of the larynx/trachea or high-riskpatients [n=623, mean     

Anaesthesia for resection of tumours in the trachea and central bronchi using the Nd-YAG-laser technique

The use of lasers in upper airway surgery is now common practice. The introduction of the Nd-YAG laser technique makes it possible to perform endoscopic resection of tumours located in the trachea and central bronchi. Usually these patients require general anaesthesia. Our experience in 13 patients using total intravenous anaesthesia and jet ventilation with air is reported. Oxygen saturation was maintained at a higher level than when the patients were breathing 100% oxygen before anaesthesia. Occasional reductions in saturation were due to airway obstruction and were easily corrected by a short interruption of the procedure. All patients tolerated the anaesthesia and surgery well. No complications related to the anaesthetic method or the use of the Nd-YAG-laser occurred. A review of the possible hazards in these procedures is given together with advice on safety precautions needed.     

Anaesthesia for maxillofacial surgery

Maxillofacial surgeons are responsible for the operative management of oromaxillofacial cancer, facial trauma, facial and dental infections, craniofacial deformities, orthognathic conditions and temporomandibular joint dysfunction. Airway management for these patients can be challenging for the anaesthetist. This article focuses upon key aspects of airway assessment and the development of a comprehensive understanding of the management of these complex patients, including recognizing impending airway compromise, advanced airway skills, rescue techniques and planning for tracheal extubation. The fundamental aspects involved in the clinical management of common maxillofacial surgical presentations are described, with reference to the most recent evidence and clinical guidelines.     

Anaesthesia for maxillofacial surgery

Maxillofacial surgeons are responsible for the operative management of pathologies such as head and neck cancer, facial trauma, infections, craniofacial deformities and temporomandibular joint dysfunction. Airway management for these patients can be particularly challenging for the anaesthetist. This article will focus on key aspects of airway assessment and the development of a comprehensive management strategy; including recognizing impending airway compromise, advanced airway management skills, appropriate rescue techniques and planning for tracheal extubation. We will describe the key aspects of clinical management for common maxillofacial surgical presentations, with reference to the most recent evidence base and clinical guidelines.     

Anaesthesia for eye surgery in paediatrics

Children and infants present for ophthalmic surgery from birth onwards. This article looks at the general anaesthetic considerations for these patients with respect to eye surgery, with particular reference to control of intra-ocular pressure, oculo-cardiac reflex, ocular trauma, postoperative nausea and vomiting, malignant hyperpyrexia, syndromes and analgesia. Specific problems such as the measurement of intra-ocular pressure, and techniques for both intra- and extra-ocular surgery are then discussed.     

Anaesthesia for maxillofacial surgery

Airway management is central to anaesthesia for maxillofacial surgery. Not only is there a shared airway to contend with, difficult airways are frequently encountered. The main pathologies that present for surgery include trauma, infection, cancer and craniofacial deformities. All of these may present an airway challenge in either elective or emergency settings but a similar approach to the airway can be used in all these scenarios. Other surgical procedures include dental extractions, temporomandibular joint (TMJ) arthrocentesis, salivary gland surgery and facial aesthetic surgery.It is vital that clear airway management plans including rescue plans are made at the outset. These must be communicated to the surgical and anaesthetic team in advance. Trauma is excluded as it will be covered in a separate review article.     

Anaesthesia for surgery of the trachea and main bronchi

Major surgery on the trachea and airway is an anaesthetic challenge, which necessitates the simultaneous control of the airway, maintenance of gas exchange and good surgical exposure. Advance planning, good communication and teamwork among surgeon, anaesthetist and theatre staff are never more important. A major indication for laryngeal and tracheal surgery is laryngotracheal stenosis, a rare condition, which can cause significant morbidity and life-threatening airway obstruction. In the era of modern medicine, post-intubation injury has superseded infection and external trauma as the commonest aetiology. Definitive surgery is usually carried out in tertiary specialist centres, where segmental resection of the trachea with primary end-to-end anastomotic reconstruction is usually the technique of choice. Provision of anaesthesia for bronchial sleeve resection and removal of inhaled foreign bodies faces similar challenges.     

Anaesthesia for surgery of the trachea and main bronchi

The anaesthetic challenges of major tracheobronchial surgery relate to airway control, ventilation management, maintaining optimal surgical exposure and appropriate patient selection. Although such surgery is generally performed in specialist centres, the strategies for dealing with central airway obstruction and bronchoscopy under general anaesthesia are of broader importance. Furthermore, an intra-thoracic airway obstruction presents difficulties that require a different mindset to the more familiar scenario of an extra-thoracic airway obstruction. Tracheal stenosis following a period of prolonged tracheal intubation is now the leading indication for tracheal resection. A standard approach involves total intravenous anaesthesia, a right-sided arterial line, epidural analgesia and early extubation. Usually, a sterile armoured cuffed endotracheal tube is placed under direct surgical vision for the period of segmental resection followed by reintroduction of the native orotracheal tube under bronchoscopic vision for the primary end-to-end anastomotic reconstruction.     

Tubeless combined high-frequency jet ventilation for laryngotracheal laser surgery in paediatric anaesthesia

BACKGROUND: High-frequency jet ventilation (HFJV) is an alternative ventilatory approach in airway surgery and for facilitating gas exchange in patients with pulmonary insufficiency. We have developed a new technique of combined HFJV utilising two superimposed jet streams. In this study we describe the application of tubeless supralaryngeal HFJV during laryngotracheal laser surgery in infants and children. METHODS: Tubeless combined HFJV characterised by the simultaneous supralaryngeal application of a low-frequency (LF) and a high-frequency (HF) jet stream was evaluated in a clinical study in 10 children undergoing elective laryngotracheal CO2 laser surgery. Additionally, pressure and flow characteristics were determined with the use of a paediatric test lung. HFJV was applied by means of a modified Kleinsasser laryngoscope with integrated metal injectors. In addition to pulse oximetry, monitoring of ECG, heart rate and blood pressure, supraglottic airway pressure was measured and arterial blood gases were analysed. RESULTS: Tubeless combined HFJV was used in 10 infants and children (mean age 4.6 yr, range 2 months-10 years) undergoing 17 consecutive endoscopic procedures with CO2 laser microsurgery of the larynx or the trachea under general anaesthesia.The mean duration of supralaryngeal HFJV was 46 min (range 15-75 min). Mean driving pressures of the HF and the LF jet streams were 0.75 bar and 0.95 bar, respectively. Inspiratory oxygen ratios were in the range 0.4-1.0. HFJV resulted in mean PaO2 and PaCO2 values of 19.7 kPa and 6.1 kPa, respectively. No complications during HFJV were observed. In the test lung, combined HFJV applied with driving pressures of 0.7-1.0 bar and 0.9-1.2 bar for HF and LF jet ventilation, respectively, resulted in maximum peak and baseline distal airway pressures of 17.6 cm H2O and 5.4 cm H2O, respectively. CONCLUSION: The application of the combined double frequency HFJV was effective in maintaining gas exchange in the presence of laryngeal or tracheal stenoses. It provided good visibility of anatomical structures and offered space for surgical manipulation, avoiding the use of combustible material inside the larynx or trachea.