Conscious sedation can offer a real alternative to those with dental phobia or patients undertaking extensive treatment. The change in regulations regarding general anaesthesia over the years has lead to an increase in uptake of sedation services in both the primary and secondary care settings.
The majority of conscious sedation in the UK is carried out using a basic technique of a single drug and one route. This is normally undertaken using either inhalation sedation (IHS) using a mixture of nitrous oxide and oxygen or intravenous (IV) sedation using a benzodiazepine usually midazolam. Sedation involving other drugs and combinations of these is usually referred to as advanced sedation (see Table 1 below).
Advanced techniques used for conscious sedation are more complex to understand and are not part of the current undergraduate training in the UK. Although advanced techniques are currently far less widely used there may be an increasing need for them in the developing implant private dental market. Extensive implant placements are becoming more the norm and often lengthening the time spent for patients in the clinical setting. Sometimes, basic sedation is insufficient in terms of efficacy and quality control for these patients. If clinicians wish to offer these techniques or refer to colleagues that undertake these services they must satisfy themselves that adequate training has taken place and the team has achieved competency in this area.
Should we be offering advanced sedation techniques for adults in the primary care setting or should cases that require a different approach always be referred to a specialist secondary care unit? I will explore these questions by discussing two recently treated sedation cases in primary care.
A new patient attended our general dental practice. She was female, aged 39 and no medical history of note ASA I. At the assessment visit she scored 24 out of 25 on the modified dental anxiety scale (MDAS) and a history of a recent failed sedation with a practitioner in the community care setting (IV midazolam had been used, but treatment had been abandoned halfway through).The planned treatment for the patient was removal of an upper last molar, which although broken down and carious appeared to be a routine extraction on radiographic and intraoral examination.
The patient had requested conscious sedation. The reason for sedation was moderate to severe anxiety and a previous history of failed local anaesthesia. Referral to a specialist unit (secondary care unit) was considered on the basis that the extraction was routine, however, the sedation would possibly be problematic due to the history.
After a full discussion of various options with the patient, consent was obtained to use an advanced sedation technique, should it be required. The patient was informed that a consultant anaesthetist would be present at the next treatment visit. It was stated to the patient if we could achieve the treatment with basic sedation we would do so and only move to an advanced technique if required.
The patient wanted this approach to avoid having to return for a second sedation appointment to re-establish new consent for an advanced approach. She stated that she: ‘Wanted her dental team to have the necessary expertise in place for this procedure should the need arise.’
During the procedure the patient had a significant amount of midazolam (9mg in total) gradually titrated and although appeared comfortable and ready for treatment remained uncooperative and combative, even with effective local anaesthesisa. Usual behavioural management techniques had also been employed but to no avail.
It was decided that further increments of midazolam would not enable effective treatment or further progression. As consent for the use of an advanced technique had been granted we proceeded to the next stage. IV propofol was then administered by computer-controlled infusion by our anaesthetist. It should be remembered that two sedatives via one route were used here in this case.
The treatment was completed successfully and the patient recovered quickly.
At a review appointment the patient scored a high mark of satisfaction with the procedure and reported that she felt happier attending the practice that she knew and was relieved that referral to a hospital setting had been avoided.
An anaesthetist or appropriately-trained second dentist/sedationist can administer propofol or opiods in combination with other drugs. This, unlike simple sedation is not a technique whereby the operator can also be the sedationist. A separate and trained sedationist is required to deliver the drug/s and monitor the patient throughout until a full recovery is made.
It is important for the sedationist and the team to be aware of any complications that can arise with the dental treatment during the procedure. For example, loose teeth fragments/restorations and water/saliva/mucus build up. These drugs, or combinations of them, can often further suppress the central nervous system and protective gag reflexes. For this reason, if working with an anaesthetist, it is wise to work with one who regularly operates in the dental field.
The referring dentist is legally responsible for the anaesthetist’s actions. It is recommended that sedation protocols should be discussed and established at the outset. These should then be recorded in the patient’s notes as a plan of action. Once effective sedation has been achieved the skills of the operating surgeon come to the fore in undertaking the dental procedure and at the same time keeping constant communication with the anaesthetist and dental nursing team.
It cannot be stressed enough that excellent communication between the team members is essential. It is always good practice to discuss the intended treatment plan and possible deviations one may encounter along the way so the anaesthetist/sedationist and the team are all fully aware from the start.
A male patient (age 48, no medications, fit and well ASA I) had been referred to the practice from a local colleague. He was very anxious, MDAS score 25 of out of 25, He stated he was needle phobic and fainted whenever a doctor or nurse had tried to take blood. He had needed a pre-medication just to attend a dental practice for routine examination in the past.
It had been many years since he had been able to undertake dental treatment, often cancelling his appointments at the last minute due to anxiety.
After clinical and radiographic examination, a realistic treatment plan was discussed with the patient. He required multiple restorations and was warned some teeth may require extraction. Initially, he only wished to consider treatment under general anaesthesia but after further discussion of the pros and cons of this, he decided to try a suitable conscious sedation technique.
Consent was duly obtained and a pre-med prescribed on private prescription (oral temazepam 20mg one tablet). To be used for the evening before the appointment to aid sleep. He was told not to drive after taking this the next morning, and advised there would be an anaesthetist present at the next visit. Interestingly, at the start of the treatment visit he stated that the night sedative ‘had been of little use’. A combination advanced sedation technique was decided upon. Initially, a small amount of midazolam followed by a continuous infusion of propofol.
Cannulation would be, as expected, a challenge. ‘Ametop’ cream was placed on an area of skin over a chosen vein and this was held in position with a dressing for 20 minutes. Inhalation sedation with nitrous oxide/oxygen was then delivered through a small nasal mask. Titration to a suitable point enabled the anaesthetist to successfully cannulate. It should be noted that nitrous oxide has a useful effect in causing vasodilation of the extremities enabling easier peripheral vein cannulation.
Once the cannula had been taped in position the flow of nitrous oxide was ceased and 100% oxygen delivered alone for two minutes. An initial dose of 2mg midazolam was then administered IV for anxiety, followed by IV propofol using a computer-controlled infusion device. In this case it should be noted that three drugs were used in two different routes, but not all at once.
The treatment was completed and took just under two hours. The patient had requested treatment in all three quadrants of the mouth to be undertaken if possible (another challenge in time). As with all sedation treatments strict post-operative instructions were given to the escort.
Here, again, close communication between the anaesthetist, the escort and dental team were vital. At a subsequent review appointment the patient scored highly on overall satisfaction and stated that from his perspective the treatment had lasted ‘about 30 minutes’.
‘General anaesthesia for dental treatment should only be used when there is no other method of pain and anxiety management appropriate for that patient’.
The current (UK) General Dental Council definition of conscious sedation states that it is: ‘A technique in which the use of a drug or drugs produces a state of depression of the central nervous system enabling treatment to be carried out but during which verbal contact with the patient is maintained throughout the period of sedation. The drug/s and techniques used to provide conscious sedation for dental treatment should carry a margin of safety wide enough to render loss of consciousness unlikely.’
UK dental sedation guidelines from all the stakeholders (DOH, GDC, SAAD, DSTG, and FGDP) state that the sedation team should try to offer the safest and simplest route to effective conscious sedation in the vast majority of cases.
We should also, however, use our experience and training to plan for success not failure.
The important point to remember in both of these cases is that they were identified during the assessment visit as possibly requiring an advanced sedation technique and these proposals were then explored with the patients. Both cases involved severe anxiety, phobia and clinical challenges. Had basic sedation with IHS or midazolam alone been attempted, failure may well have ensued with added frustration and wasted time for both parties.
At the assessment visit it is good practice to formulate a ‘sedation care plan’ for the patient. Thought should be given to a ‘what if scenario’. In our experience, and in audit of sedation cases, only a small percentage of cases currently require these advanced techniques.
With the advent of long implant cases and ‘same day smiles’ increasing in popularity across the UK, we may see a change, with an increasing need for advanced sedation techniques. Expectations of patients and implantologists are rising.
Current basic sedation techniques are not always ideal for some of these cases. There may be a need for an improvement in the range and quality of sedation services offered to the high street GDP in the future.
During extensive treatment, the patient may spend many hours in the clinical setting so sedation could prove useful, not only to aid extensive placement of implants and reduce operator stress but also from the patient’s perspective of reducing the extended time spent in the ‘treatment chair’. Ideally we should strive to offer our patients an expedient post-treatment and clear-headed recovery.
Basic sedation with nitrous oxide and oxygen or IV midazolam alone does not always lend itself well to extensive cases of this nature. The patient may be given a substantial dose of sedative over a period of three or more hours. This is sometimes to ‘maintain an adequate level of patient compliance’ for the implantologist to complete the treatment. This can then result in a longer post-operative recovery period and occasionally produce a narrower margin of safety for the patient. IHS may not always be effective on its own and often requires continual behavioural support from the team.
These cases are the exception, not the rule. Dentistry on the high street is developing at a pace with new advances in surgical techniques being introduced all the time. Patients are being offered these advances and are being treated for longer periods of time in this setting and in some cases over a whole day. Some patients wish to avoid referral to an unfamiliar hospital setting, therefore there is a need for some of our patients to access advanced sedation care of this type.
These sedation techniques do have a place in the primary care setting at certain times. As always, a careful and thorough assessment of the patient and the proposed plan is required to select the appropriate technique – be it basic or advanced sedation – and this should be undertaken by a team trained and experienced in the use of that chosen technique.
The planned approach of using the right team in the right place, using the right technique helps achieve a wider margin of safety and increases patient satisfaction for all of our patients in the future.
I would like to acknowledge the support of my sedation nurses but especially Dr Giju George, consultant anaesthetist Liverpool University Dental Hospital for his contribution.
1. Humphries GM Morrison T and Linsaysje (1995) ‘The Modified Dental Anxiety Scale: Validation and United Kingdom Norms’ Community Dental Health 12,143-150
2. Conscious Sedation in the Provision of Dental Care: Standing Dental Advisory Committee (2003)
3. Standards for Dental Professional: General Dental Council (2005)
4. Advanced Conscious Sedation techniques for Adult Dental Patients – Independent Expert Group on Training Standards for Sedation in Dentistry