Setting up a Service- Facility, Personnel, Equipment:

This primer is if you are a dentist and you wish to establish a practice that offers sedation dentistry along with the assistance of an anaesthetist but are uncertain of the requirements. We of course would prefer you to set up this service with one of our own anaesthetists at Elite Anaesthesia, and invite you to contact our Director, Dr Brett Wells, to discuss your specific needs.

This primer is very general in scope, and not intended to be advisory in any way, and should not be used a substitute for the relevant guidelines and expert advice regarding your own situation, particularly given we may make omissions or inadvertently include factual errors. This should be read as a clear disclaimer that each dentist is responsible for their own arrangements within their practice, and this should focus attention on ensuring those arrangements are suitable. Your assessment of your arrangements should be informed by the relevant guidelines which we include on our webportal, although the most recent versions of these guidelines should be downloaded directly from the Dental Board of Australia, the Australian Dental Association, and the Australian and New Zealand College of Anaesthetists.

When setting up a practice some thought should go into the suitability of the Facility, the likely patient population, and the required extent of sedation (or anaesthesia) you anticipate for your dental procedures. In particular, there are a few vital conceptual differences to consider in envisaging either conscious sedation or general anaesthesia for dental procedures:

1. The basic differentiation in patient population is in age, from children to adults, and in their relative health status and other features (e.g. airway examination) that may impact of their general risks for conscious sedation or general anaesthesia

2. The basic differentiation in location or facility for a dentist is whether the procedure should occur in the dentist’s own dental surgery or if a dedicated day surgery environment is more suitable.

3. The basic differentiation in extent of sedation-anaesthesia is between that of conscious sedation, where the patient still responds purposefully to spoken command or light tactile stimulation, and that of a general anaesthesia, where the patient is in a drug-induced state whereby they do not have any purposeful response to stimulus.

Unfortunately, many of these differentiations are not as explicit as they may initially appear. For example, in terms of the depth of anaesthesia, PS9/2014 ANCZA points out in its discussion of the aims and risks of procedural sedation that:

“Practitioners who administer procedural sedation and/or analgesia should be aware that the transition from complete consciousness through the various depths of sedation to general anaesthesia is a continuum and not a set of discrete, well-defined stages. The margin of safety of drugs used to achieve sedation and/or analgesia varies widely between patients and loss of consciousness with its attendant risk of loss of protective reflexes may occur rapidly and unexpectedly”.

In our view, this is one of the most important points about conscious sedation: that is, that the remarkable variability between patients in their response to the same dose of an anaesthetic drug means that there is an inherent risk that a patient intended for conscious sedation could rapidly transit to general anaesthesia.

In practice, this is not uncommonly seen by anaesthetists, when occasionally a small dose of a drug given by an anaesthetist to relieve a patient's anxiety results in an unexpected loss of consciousness and the requirement for transient cardiorespiratory support. While this is not a particular problem for either the patient or the qualified and observant anaesthetist, it is a problem if the conscious sedation is done by a practitioner who does not have the a skill set to manage this occurrence. The direct learning principle is that any proceduralist performing conscious sedation needs to have some skills in managing the patient who transits to general anaesthesia given that it is inevitable that this will occur in one of their patients, somewhere, at sometime. The PS9/2014 ANZCA guideline continues to discuss what risks need to be managed, and we refer you to the document for further details. The Australian Dental Association also has a good document on conscious sedation in dentistry (Policy Statement 6.17) which also highlights this risk, and this should be mandatory reading.

Similarly, in terms of the location or facility, the differences are not always clear: in this case PS55/2012 ANZCA assists us in describing the range of physical spaces, staffing, equipment and drugs required for the conduct of anaesthesia. To satisfy these criteria is not really location-dependent, as either a dental surgery or a dedicated day surgery (viz, day-case hospital) may be considered suitable places if these criteria are satisfied.

Conscious sedation often occurs in both dental surgery and dedicated day surgery environments. However, the intention of conscious sedation is simply to assist the patient is transiting through an uncomfortable or relatively tedious procedure with as little memory or inconvenience as possible. There is no intention to either deeply sedate a patient or transit them to a general anaesthetic. Even so, there remain substantial equipment and training requirements in the performance of conscious sedation, in part to protect the patient who experiences an unexpected complication or otherwise inadvertently transits into a deeper state of anaethesia.

There are a range of practitioners that are eligible to do this sedation, including dentists with appropriate postgraduate qualifications, and non-specialist medical practitioners with an appropriate skillset in sedation. However, these practitioners are not eligible to purposefully manage a patient to general anaesthesia, which takes fully five years of specific post-graduate specialist training following junior doctor training, and this remains (and in our view should remain) the province of an anaesthetist.

Of interest is that much of the equipment required for conscious sedation is perfectly mobile for the properly prepared practitioner, and the mandatory equipment that is more bulky (e.g. defibrillator) can be readily purchased by a dental practice. These equipment requirements are readily identified in the relevant documents of both the Austrlaian Dental Board, Australian Dental Association, and Australian College of Anaesthetists.

We at Elite Anaesthesia would be delighted to do conscious sedation for a suitably selected population of patients in a facility that is properly equipped and accredited, whether that be the dentists own practice or a dedicated day surgery.

General anaesthesia is quite a different matter, and there are greater physical and logistical requirements involved irrespective of th specific location where this is intended to take place. It is also important to realise that while a small amount of conscious sedation can be relaxing for a patient, this contrasts with a general anaesthetic that can impose a substantially greater physiological burden on the patient. In addition, the broader spectrum of drugs used invites a much broader range of possible complications.

This is readily illustrated- consider a general anaesthetic for a dental procedure, say an extraction of wisdom teeth. This may require the patient to be intubated with a nasal or oral tube, in which case usually a muscle relaxant of some description will need to be given to facilitate that intubation. The experienced anaesthetist appreciates that the use of muscle relaxants in any operation substantially increases the risk of anaphylaxis. The incidence of anahylaxis is not as rare as one would suppose, as most practicing anasthetists will experience one of more episodes in a busy professional working life (we certainly have). For this to occur in a dental surgery, even with supportive drugs and equipment, such as adrenaline, the ability to ventilate, and a defibrillator, a dental surgery remains a highly unfavourable environment for managing this complication, especially if a full-blown cardiorespiratory resuscitation is required. It would also be necessary to transfer the patient to a high-level care facility such as the local tertiary hospital with the inevitable challenges that are involved, and the guidelines in fact mandate that the practitioner has a prior plan is in place to manage such as situation before commencing the procedure. Anaphylaxis can occur in even the healthiest patients, and it is hard to conclude that the outcome for a patient in this circumstance would be equivalent compared to if they had been in a more supported day surgery or in a private or public hospital environment. A similar argument can be applied to other anaesthetic-associated complications such as malignant hyperthermia, which requires a full spectrum of facilities unlikely to be found at a dental surgery, albeit mandated by PS55/2012 ANZCA, although in fairness many of those precipitating drugs could readily be avoided for dental surgery.

On the other hand, there has been a considerable evolution in Office Based Anaesthesia internationally (e.g. the United States) and to some extent in local practice (especially in Victoria), and there is no doubt that the actual absolute risk of an adverse event is probably relatively small, and the bulk of evidence is that the vast majority of patients would have no problem in this environment. Thus in principle it is possible to examine the feasibility of a local dental practice for general anaesthesia, set up a compliant facility including all the anaesethetic infrastructure, and maintain that practice environment in compliance with the relevant legislative conditions and guidelines. As with conscious sedation, the bulk of this equipment could be ambulatory, and it is predominantly the suitability of the physical space and other fixed equipment (e.g., the chair, the access) that governs whether a particular location is currently suitable. Common sense needs to apply as well, as although in an ideal world we would do all our procedures in a facility that has the full spectrum of support, including intensive care, to manage any conceivable complication, this is simply not practical either economically or logistically for the vast bulk of procedures, which is why we have facilities with differentiated levels of care (e.g. the office, day surgeries, private hospitals, public regional hospitals, public tertiary referral facilities).

There are certainly some organisations that offer general anaesthesia in a dental practice environment within Australia, but it is fair to say that it remains an area of some medico-legal uncertainty, and the practitioner needs to appreciate that if such an arrangement is envisaged. Indeed, each individual dentist needs to form their own view on the matter, in consultation with their anaesthetist, and obtain appropriate medico-legal advice, as we have done ourselves. The main goal should be to attempt to avoid complications occurring in the first place, by fine-tuning the anaesthetic to avoid likely precipitants for problems, selecting only suitable healthy patients, and also finally having a clear and understood plan to manage any complications should they occur in what is an environment with a limited ability to escalate care, viz. have a plan to transfer the patient.

The current view of Elite Anaesthesia is that given the prevailing medicolegal framework, if general anaesthesia is envisaged, then this should in most cases occur in either a day hospital or private hospital environment unless a dental surgery is set up with an equivalent facility. There is no great burden in this choice, as we personally observe significant efficiency gains given these day-case facilities are set up for high turnover at low cost relative to the larger private hospitals, and often come at limited cost to the patient who has private hospital cover. For those without private health insurance there will be a facility fee, but in our view this choice in most cases provides the patient with an improved level of support relative to at least the usual dental surgery.

The final area we would like to discuss is the patient population that is suitable for conscious sedation in a dental surgery environment. In general the suitable patient would be well and healthy, or at most have a mild disease that does not impair them functionall. This effectively describes what is known as an ASA1 or ASA2 patient on the American Society of Anaesthetist’s Physical Status Classification System. We have a range of other vetting criteria, including those with gastric bands, who we believe represent an unsuitably high aspiration risk, those with substantive obesity which multiplies their personal risks, or patients with clinically relevant obstructive sleep apnoea to name only a few criteria. In fact, we believe that one of the major predictors of a positive patient outcome for conscious sedation in a dental surgery environment is suitable patient selection, and we note this is a point made also by the Australian Society of Dental Anaesthesiology.

Finally, when considering patient selection, it is important to consider which patients will not really tolerate conscious sedation and will inevitably require deeper levels of sedation that can transit to a general anaesthesia: this “at risk” group includes children and the intellectually disabled. Given we regularly anaesthetise small childre we have a healthy respect for the rapid changes that are unique to their physiology under an anaesthetic, and in our view children are unsuitable for conscious sedation in a dental surgery environment. However, in most cases they are perfectly suitable for a general anaesthetic in an appropriately equipped and supported day hospital or private hospital. In terms of the intellectually impaired, apart form not being able to tolerate lighter levels of sedation, they can also have multiple co-morbidities (e.g. those with Down Syndrome=Trisomy 21), some of which may be unknown, that can negatively impact on ensuring a positive outcome under either conscious sedation or a general anaesthetic.

All these factors suggest that a screening process is required, and we at Elite Anaesthesia contact all our patients for dental procedures with our preoperative health survey and follow up with any issues of concern. This can also be done at the point of initial contact in the dental surgery, and we can provide guidance for our regular dentists as to streaming of patients for conscious sedation in dental surgeries through to general anaesthesia in a day surgery environment.

There are many other factors to be considered in setting up adequate facilities to support conscious sedation in your dental surgery and your anesthetist is your pre-eminent specialist in considering these matters in association with the relevant guidelines.

Do not hesitate to contact our director, Dr Brett Wells, if you require our services.