Chapter 12: Guidelines for the Provision of Anaesthesia Services for ENT, Oral Maxillofacial and Dental surgery 2020

Published: 31/01/2020

Introduction

Head and neck surgery includes a wide spectrum of surgical interventions, ranging from short daycase procedures to long and complex operations.1 The requirements for providing anaesthesia services for routine head and neck surgery, such as tonsillectomy, will be different to those required to provide anaesthesia for major or complex surgery. There should be recognition that routine head and neck surgery may include patients with complex and difficult airways due to disease or previous treatment.

Anaesthesia for surgery of the head and neck includes the disciplines of ear, nose and throat (ENT), oral and maxillofacial, and dental surgery. A significant proportion of head and neck surgery is of a routine nature, and much of the service is ideally provided for by a dedicated daycase facility.

In some instances, such as surgery on the base of the skull and craniofacial surgery, formal integration with a neurosurgical and plastic surgical service may be required. Owing to the broad scope of patients requiring anaesthesia for head and neck surgery, multidisciplinary team working is essential.

Conditions that require head and neck surgery affect patients of all ages, and a significant proportion are children. The treatment of neonates, young children with significant comorbidity, and children with complex surgical conditions should take place in units with specialist paediatric facilities, unless immediate emergency care is required prior to transfer to a specialist paediatric facility.2 Minor procedures such as teeth extraction, the removal of tonsils or adenoid tissue, and the insertion of grommets can be carried out on children in a general hospital setting.

The indications for head and neck surgery vary widely, from minor infective and inflammatory disorders to extensive malignant disease. In the latter case, surgical excision and reconstruction, often using free tissue transfer, requires complex perioperative anaesthetic management.

It is common for head and neck surgery to encroach upon the airway or to require changing the airway during surgery. It is therefore essential that there is close liaison and good teamwork between theatre teams – surgeons, anaesthetists, anaesthetic assistants, and scrub staff – in all cases where a shared airway is planned and undertaken.1

All dental work requiring general anaesthesia should be performed in a hospital setting.3 Special care dentistry often requires additional resources to provide appropriate perioperative care.

1. Staffing requirements

1.1

A clinical lead (see glossary) for head and neck anaesthesia should be appointed in each hospital providing anaesthetic services for head and neck surgery.1,4

C Strong
1.2

One or more named senior anaesthetists with appropriate training and expertise, and with an interest in head and neck surgery, should be responsible for directly or indirectly overseeing all complex and/or major head and neck procedures.5 All other regular sessions should have either a named consultant or an SAS doctor with appropriate skills assigned to them.6

C Strong
1.3

A Royal College of Anaesthetists/Difficult Airway Society airway lead should be appointed in all hospitals providing anaesthetic services.7

B Strong
1.4

Where scheduled procedures cannot be accommodated within normal list times, anaesthesia departments should make arrangements for anaesthetists to be relieved by a colleague.8

C Strong
1.5

There should be an appropriately trained theatre team including an on-call consultant anaesthetist 24/7 to provide anaesthesia for emergency head and neck surgery in head and neck cancer centres and in hospitals with an emergency department (ED).9

C Strong
1.6

Consideration should be given to identifying anaesthetists with advanced airway experience to support colleagues providing care to patients with complex airway emergencies.

GPP Moderate
1.7

Patients who have had a recent tracheostomy or airway surgery returning to a general ward, should be cared for by adequate levels of nursing staff who are skilled in the care of the surgical airway and be aware of the specific risks involved.4,10,11,16,22

C Strong
1.8

Many head and neck cancer patients have significant comorbidities that may require optimisation prior to surgery. There should be a lead anaesthetist for preoperative assessment who works closely with an appropriate preoperative assessment team.12

C Strong
1.9

Where Light Amplification by Stimulated Emission of Radiation (LASER) surgery to the head and neck is performed staff must be appropriately trained in its safe use.13,14 A LASER protection advisor (LPA) should be consulted or appointed according to devolved administration or local authority regulations, and a local safety officer and/or an operational LASER protection supervisor (LPS) appointed according to local advice from the LPA.15

C Mandatory
1.10

Nursing and theatre staff trained to manage patients with a tracheostomy should be available in recovery areas of hospitals.16,11

C Strong
1.11

Recovery facilities should be staffed and have appropriate anaesthetic support until the patient meets the agreed discharge criteria.33

C Strong

2. Equipment, services and facilities

Equipment

2.1

Many patients with intraoral malignancy, craniofacial disorders and traumatic facial injuries present with a predicted difficult intubation. There should be a full range of equipment relating to the management of the anticipated difficult airway available within the theatre suite. This should include equipment for videolaryngoscopy, fibreoptic intubation, high-flow nasal oxygen therapy (HFNO), and equipment to perform front of neck access (FONA).17,18,19

B Strong
2.2

An adequate range of tracheostomy tubes, including adjustable flange tubes with inner tubes, should be stocked and standardised within the hospital.11,16

C Strong
2.3

The use of LASERs during head and neck surgery is common. Where lasers are in use, the correct safeguards, in accordance with BS EN 60825, must be in place.13 Theatre door screening and LASER warning systems must be provided. The appropriate wavelength specific protective eye goggles must be worn.15,20

C Mandatory
2.4

When undertaking specialist techniques, such as high frequency jet ventilation in laryngotracheal surgery, the appropriate equipment and training to safely undertake this should be available.

GPP Strong
2.5

Preoperative nasendoscopy equipment should be available to aid the identification of the difficult airway and to enable advance planning for anticipated problems.1,7

B Strong
2.6

When transferring patients requiring postoperative care in a critical care facility additional equipment should be available. This should include portable non-invasive and invasive monitoring, emergency transfer packs, portable ventilators, and end tidal CO2 monitoring.7,21

B Strong
2.7

Any clinical area caring for patients with a tracheostomy should provide the recommended bedside equipment and the locally ‘immediately available’ emergency equipment, as indicated in the UK National Tracheostomy Safety Project Guide.11,22

C Strong
2.8

The use of bedhead signage to indicate which patients are not suitable for bag-mask ventilation and/or oral intubation in the event of emergencies is advised.22

C Strong
2.9

Throat packs are no longer recommended for routine insertion, but should their use be judged necessary a protocol governing their use should exist.23

C Strong
2.10

Throat packs are no longer recommended for routine insertion, but should their use be judged necessary a protocol governing their use should exist.23

C Strong

Support services

2.11

Patients awaiting complex head and neck surgery (for benign or malignant pathology), or with significant comorbidities, should be seen in the preassessment clinic by an experienced anaesthetist who ideally will be involved in their perioperative pathway.24

C Moderate
2.12

Short and long term outcomes in head and neck cancer patients can be improved by certain lifestyle changes such as cessation of smoking, alcohol reduction and improved nutrition.25 The preoperative assessment clinic should be used as an opportunity to implement these lifestyle changes, with access to the appropriate support services (e.g. dietetics, smoking cessation services) when required.

C Strong
2.13

Access to radiological imaging should be available preoperatively to aid in the identification and management of the difficult airway.

GPP Strong
2.14

Where major head and neck surgery is performed, there may be a regular requirement for elective level 2 and level 3 critical care facilities. This should be available in the same hospital for those trusts or boards providing complex reconstructive procedures.5

C Strong
2.15

When the postoperative destination is a level 2 critical care unit, patients should remain in the postoperative care unit until they meet discharge criteria, including having regained a sufficient level of consciousness.

GPP Strong
2.16

When fibreoptic scopes are used in head and neck surgery, the general principles for scope decontamination, as outlined by the Department of Health, must be followed.

C Strong

Facilities

2.17

Facilities should be available, or transfer arrangements should be in place to allow for the overnight admission of patients who cannot be treated as daycases and for those patients who require unanticipated admission to hospital.

GPP Strong
2.18

Wherever possible, patients who have undergone airway related surgery should be cared for in the early postoperative period on a dedicated head and neck surgery ward with adequate levels of medical and nursing staff who are familiar with the recognition and management of airway related problems.4,10

C Strong
2.19

Patients presenting with impending airway obstruction may need emergency airway intervention and surgery. The ability to provide this service dictates that an appropriately staffed and equipped theatre be available 24/7.

GPP Strong
2.20

The location of the head and neck ward should ideally facilitate a rapid return to theatre should the need arise, since postoperative airway complications can occur following even minor surgical procedures. Consideration should be given to the proximity between head and neck wards, theatre, and critical care facilities when planning head and neck services.

GPP Aspirational

3. Areas of special requirement

Children

Head and neck surgery is performed on a significant number of children. General recommendations for the provision of anaesthetic services for children and young people are described in chapter 10.2

3.1

The treatment of neonates, young children with significant comorbidity and children with complex surgical conditions should be provided in specialist paediatric facilities, unless immediate emergency care is required prior to transfer to a specialist paediatric unit.

C Strong
3.2

In an emergency situation involving a child requiring anaesthesia for an airway or head and neck procedure, the most experienced available anaesthetist and surgeon would be expected to provide life-saving care when transfer to a specialist facility is not feasible.

C Strong
3.3

Simple procedures such as dental extractions, tonsillectomy and adenoidectomy, and the insertion of grommets are examples of surgery suitable to be performed in a general hospital setting.

C Strong

Pregnant patients

Recommendations for the provision of anaesthesia for non-obstetric surgery in pregnant patients can be found in chapter 5.9

3.4

Where possible surgery should be postponed until after delivery. If this is not possible, for example in cases of head and neck cancer, a multidisciplinary team approach is highly recommended, typically involving anaesthetists, surgeons, oncologists, obstetricians, midwives and paediatricians and, in cases of thyroid malignancy, endocrinologists.

C Strong

Obstructive sleep apnoea

There is an inherent risk of increased morbidity and mortality related to anaesthesia and obstructive sleep apnoea (OSA). This risk may be increased in head and neck surgery. When providing head and neck anaesthesia services for adult patients with known (OSA)/or a STOP-Bang score > 3 (intermediate to high risk for OSA) the following recommendations may need to be considered.27,28

3.5

Sleep studies and a trial of continuous positive airway pressure (CPAP) are recommended or should be considered, where possible, prior to elective surgery in order that appropriate services and planning may be allocated to them.29

B Strong
3.6

Postoperative airway issues can occur even following minor surgical procedures, and these should be anticipated and planned for.30,31 There may be a need to consider elective postoperative care in an appropriate critical care unit or a specialist postoperative ward.32,33

C Moderate

Obesity

3.7

When providing head and neck anaesthesia services for morbidly obese patients (BMI ≥40), a number of special requirements will need to be considered as set out in chapter 3 (section 3.3-3.7) and chapter 4 (section 3.24-3.25).33,34

C Strong
3.8

Obesity hypoventilation syndrome (Pickwickian syndrome) is associated with a higher risk of perioperative complications than OSA, and this should be given due consideration in obese patients with or without a STOP-Bang score >3.35

B Strong

Transoral robotic surgery

Transoral robotic procedures (TORS) are currently performed for oropharyngeal cancer and OSA. These may range from minor resection, for example tongue mucosectomy, to complex resection or salvage surgery following primary chemoradiotherapy.

3.9

All personnel involved with TORS should be appropriately trained, including knowledge of how to perform an emergency dedock procedure (see glossary). An emergency dedock should be regularly rehearsed by the team, and discussed as part of the briefing prior to TORS.

GPP Strong
3.10

Consideration should be given to anaesthetic equipment specific for TORS, for example extra-length anaesthetic circuit, patient eye protection, tracheal-tube fixation, laser safety and dental protection.

GPP Strong

Dentistry

3.11

General anaesthesia for dental procedures should be administered only by anaesthetists in a hospital setting as defined by the Department of Health report reviewing general anaesthesia and conscious sedation in primary dental care.3

C Strong
3.12

Guidelines, for example those published by the Association of Paediatric Anaesthetists of Great Britain and Ireland, should be followed for the management of children referred for dental extractions under general anaesthesia.36 Further information on anaesthesia for community dentistry is available in chapter 7.

C Strong
3.13

Anaesthetists providing sedation for dental procedures should follow the guidance on safe sedation published by the Academy of Medical Royal Colleges and Intercollegiate Advisory Committee on Sedation for Dentistry (IACSD).37,38

C Strong

Special care dentistry

Special care dentistry (SCD) is a specialist field of dentistry that provides oral care services for vulnerable adults with physical, medical, developmental, or cognitive conditions which limit their ability to receive routine dental care.39 General anaesthesia for dental procedures forms an important aspect of SCD, and a close working relationship is needed between the dental team, the anaesthetist and the other multidisciplinary teams involved. Patients in this vulnerable group require appropriate access, communication and perioperative care appropriate to their individual needs.40

3.14

Informed consent may not be possible for adults who lack the mental capacity to make decisions for themselves; such patients should not be asked to sign a consent form if they do not have the legal capacity to do so. Standard operating procedures must be compliant with the Mental Capacity Act 2005.41 A high level of integrity should be maintained, and good documentation is essential.

C Strong
3.15

A ‘best interests’ meeting will be needed where an adult (over 16 years old) lacks mental capacity to make significant decisions for themselves and needs others to make those decisions on their behalf.41

M Mandatory
3.16

Establishing a successful SCD anaesthetic service in hospitals requires suitably trained staff with an understanding of specific perioperative challenges in this group and with experience in the management of shared airways.39

C Strong

4. Training and education

4.1

Patients requiring head and neck procedures should be managed by anaesthetists who have had an appropriate level of training in this field and who have acquired the relevant knowledge and skills needed to care for these patients.42,43

C Strong
4.2

In order to maintain the necessary repertoire of skills, consultant anaesthetists and SAS doctors providing a head and neck service should have a regular commitment to the specialty, and adequate time should be made available for them to participate in a range of relevant continuing medical education activities, including simulation, human factors and team training.7,44

C Strong
4.3

Head and neck surgery provides an excellent opportunity for the formal and systematic training of anaesthetists in the use of advanced methods for airway management and the shared airway, including videolaryngoscopy, fibreoptic intubation, and jet and apnoeic oxygenation techniques. Where possible, additional equipment such as monitors, video recorders and airway simulators should be made available to facilitate this important aspect of anaesthetic education. Time to educate all anaesthetists in elective, emergency and advanced airway management techniques should be encouraged.

GPP Strong
4.4

All hospitals providing care to tracheostomy patients should have trained staff (medical and nursing) available to care for these patients. Training should be regularly updated.11,45

C Strong
4.5

Departments providing head and neck LASER surgery must have staff trained in the safe use of LASERS and these staff should be available for all LASER cases.13,14 Training should be regularly updated, and opportunities made available for education in safe LASER use in the theatre complex. Staff involved in LASER surgery should be trained in how to reduce the risk of, and manage, a laser fire if one should occur.46

M Mandatory

5. Organisation and administration

5.1

All theatre staff should participate in the World Health Organization checklist process (or an appropriate locally agreed process), with reference made to specific airway strategies for anticipated airway problems and to ensure that all necessary equipment is available.10

C Strong
5.2

Airway management should be guided by local protocols,10 including formal adoption of national guidelines such as Difficult Airway Society intubation, extubation, paediatric and obstetric guidelines.17,47,48

C Strong
5.3

A multidisciplinary team (MDT) may be required, and this may include plastic, vascular or neurosurgical surgeons for complex head and neck surgery. Anaesthetists may be required to attend MDT meetings preoperatively, and this should be included in their job plan if it forms a regular commitment.

GPP Aspirational
5.4

Access to an emergency operating theatre staffed with appropriate personnel should be available for all cases requiring urgent surgical management, for example obstructed airway or bleeding tonsil.

GPP Strong
5.5

A clear referral pathway should exist for the eventuality of patients requiring transfer to a regional centre.

GPP Strong
5.6

There should be at least one three-session operating day per week as required, dedicated to complex head and neck surgery,5 with provision made for adequate rest breaks.

C Strong

6. Financial considerations

Part of the methodology used in this chapter in making recommendations is a consideration of the financial impact for each of the recommendations. Very few of the literature sources from which these recommendations have been drawn have included financial analysis.

The vast majority of the recommendations are not new recommendations, but are a synthesis of already existing recommendations. The current compliance rates with many of the recommendations are unknown, and so it is not possible to calculate the financial impact of the recommendations in this chapter being widely accepted into future practice. It is impossible to make an overall assessment of the financial impact of these recommendations with the currently available information.

6.1

Specialist airway equipment, for example videolaryngoscopes, high frequency jet ventilators, transnasal high-flow humidified oxygen delivery devices and portable ultrasound machines should be included in annual budget planning and procurement processes.17

GPP Strong

7. Research, audit and quality improvement

7.1

In addition to routine audit and the reporting of critical incidents, any morbidity relating to airway management should be presented at departmental clinical governance meetings and documented for audit purposes.

GPP Strong
7.2

Head and neck anaesthetists should actively engage and contribute to regional and national head and neck outcome databases and audit.5,49

C Strong

8. Implementation support

The Anaesthesia Clinical Services Accreditation (ACSA) scheme, run by the RCoA, aims to provide support for departments of anaesthesia to implement the recommendations contained in the GPAS chapters. The scheme provides a set of standards, and asks departments of anaesthesia to benchmark themselves against these using a self-assessment form available on the RCoA website. Every standard in ACSA is based on recommendation(s) contained in GPAS. The ACSA standards are reviewed annually and republished approximately four months after GPAS review and republication, to ensure that they reflect current GPAS recommendations. ACSA standards include links to the relevant GPAS recommendations, so that departments can refer to them while working through their gap analyses.

Departments of anaesthesia can subscribe to the ACSA process for an appropriate fee. Once subscribed, departments are provided with a ‘college guide’ (a member of the RCoA working group that oversees the process), or an experienced reviewer to assist them with identifying actions required to meet the standards. Departments must demonstrate adherence to all ‘priority one’ standards listed in the document to receive accreditation from the RCoA. This is confirmed during a visit to the department by a group of four ACSA reviewers (two clinical reviewers, a lay reviewer and an administrator), who submit a report back to the ACSA committee.

The ACSA committee has committed to building a ‘good practice library’, which will be used to collect and share documentation such as policies and checklists, as well as case studies of how departments have overcome barriers to implementation of the standards, or have implemented the standards in innovative ways.

One of the outcomes of the ACSA process is to test the standards, and by extension the GPAS recommendations, to ensure that they can be implemented by departments of anaesthesia and to consider any difficulties that may result from implementation. The ACSA committee has committed to measuring and reporting feedback of this type from departments engaging in the scheme back to the CDGs updating the guidance via the GPAS technical team.

9. Patient information

Recommendations on the provision of patient information and consent are comprehensively described in chapter 2.

9.1

As part of a difficult airway follow-up, patients should be informed in writing about any significant airway problem encountered, and be advised to bring it to the attention of anaesthetists during any future preoperative assessment.

GPP Strong

Areas for future development

Following the systematic review of the evidence, the following areas of research are suggested:

  • standardisation of airway equipment, e.g. airway rescue trolleys
  • national reporting systems
  • the DAS alert card50
  • use of virtual preoperative assessment clinics for assessment of long-distance patients in tertiary centres
  • provision of a robust preoperative pathway with a view to optimising patients' physiology prior to undertaking major head and neck surgery, and an enhanced recovery pathway to reduce complications and length of stay.

Glossary

Head and neck surgery – for the purpose of this document the term head and neck surgery will include ENT, oral and maxillofacial, and dental surgery, unless otherwise stated.

Clinical lead – SAS doctors undertaking lead roles should be autonomously practicing doctors who have competence, experience and communication skills in the specialist area equivalent to consultant colleagues. They should usually have experience in teaching and education relevant to the role, and they should participate in quality improvement and CPD (continuous professional development) activities. Individuals should be fully supported by their clinical director, and be provided with adequate time and resources to allow them to effectively undertake the lead role.

Dedock – to remove the robot from the patient quickly.

STOP-Bang – Snoring, Tiredness, Observed apnoea, high blood Pressure (STOP); BMI, Age, Neck circumference, and Gender (Bang).

References

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