Pharmacological management of pain and anxiety-Paediatric Dentistry

Introduction
Effective pain management of a child, especially an anxious one, is a challenge to every dentist. The need for good management of anxiety and pain in paediatric dentistry is paramount. A common cause of complaint from parents and their children is that a dentist 'hurt' unnecessarily. Such a complaint can jeopardize access to life-long dental care.
Children are anatomically and physiologically different from adults. The anatomy of the airway means that breathing is through a narrower, more fixed 'wind pipe'. Physiologically, a child is less capable of taking in a bigger volume of air even when urgently required. Coupled with this, both the demand for oxygen (consumption) and the incidence of periodic breathing and apnoeas are higher compared to adults. These differences mean that a child can become hypoxic more easily.

Children's perception of pain
A child's perception of pain is purely subjective and varies widely, particularly with age. Infants up to about 2 years of age are unable to distinguish between pressure and pain. After the age of approximately 2 and up to the age of 10, children begin to have some understanding of 'hurt' and begin to distinguish it from pressure or 'a heavy push'. The problem is that it is not always possible to identify which children are amenable to explanation and who will respond by being co-operative when challenged with local anaesthesia and dental treatment in the form of drilling or extractions. Children over the age of 10 are much more likely to be able to think abstractly and participate more actively in the decision to use local anaesthesia, sedation, or general anaesthesia. Indeed, as children enter their teenage years they are rapidly becoming more and more like adults and are able to determine more directly, sometimes aggressively, whether or not a particular method of pain control will be used. The response is further determined by the child's coping ability influenced by family values, level of general anxiety (trait), and intelligence.
Key PointsChildren are anatomically and physiologically different from adults this results in them becoming hypoxic more easily.Children's response to pain is influenced by age, memory of previous negative dental experience, and coping ability.
Consent
Before you can do anything to a patient, even a simple examination, consent must be obtained. Consent may be implied, verbal, or written. The main purpose of written consent is to demonstrate post hoc, in the event of a dispute, that informed consent was obtained. It has the considerable advantage of making clinicians and patients pause to consider the implications of what is planned and to weigh the advantages and disadvantages so that a reasoned and informed choice can be made. The responsibility for informed consent is often shared between the referring primary care dentist and the secondary care service provider, especially where sedation and general anaesthesia are involved. Many health trusts and other employing authorities are increasingly demanding that written consent is obtained for all procedures. This is especially difficult now as the lower age of consent is no longer specifically limited. The sole criterion is whether or not the patient is 'able to understand' the procedures and their implications. If so, the patient is considered 'competent' and the child may give (or refuse) consent. It is usual to arrive at a consensus view among parents, child, and dental surgeon. A sufficiently informative entry should be placed in the patient's case records. As a pragmatic rule the age of 16 years still acts as a guide. But if a procedure is proposed and a child under 16 years says 'no' then consent has been refused. Fortunately, in paediatric dentistry the prospect of a life-saving operation is rare so a refusal of consent can be managed by a change in the procedure or by establishing a temporal respite. The current advice from the protection societies is that written consent must be obtained for a course of treatment. The plan of treatment proposed must indicate the nature and extent of the treatment and the approximate number of times that local anaesthesia and/or sedation is to be used. There is no need to obtain written consent for each separate time that sedation is used. If the plan of treatment changes and along with it the frequency or nature of sedation, then it is prudent to obtain written consent for the change. The greater risks associated with general anaesthesia require specific written consent for each and every occasion that treatment is carried out under general anaesthesia. Examples of suitably worded forms are available from the Medical Defence Societies.
Key PointsA conference that involves both the parent and child helps to gain informed consent:     -discuss the dental problems;     -discuss the treatment options/alternatives;     -agree the treatment plan.Write-up in the case record.Obtain written (signed) consent
Systemic pain control
Children may need pain control for 'toothache' for a day or two before the removal of carious teeth. Often, the teeth are also abscessed so that it is necessary to combine antibiotic therapy with analgesia to obtain optimum pain relief. Additionally, analgesia is required postoperatively usually after dento-alveolar surgery.
The most common method of administration is by mouth. Small children, and some recalcitrant adolescents, refuse to take tablets so liquid preparations are needed. If other methods of administration, such as intramuscular or intravenous, are required then these injections should be administered by clinical staff experienced with these special techniques. Rectal administration is increasingly common as absorption from the rectal mucosa is rapid. If such a route of administration is to be used, specific consent must be obtained. It should be remembered that the dose for children of different ages needs to be carefully estimated to avoid the risk of an overdose (dangerous) or of an underdose (ineffective). The parents must be advised that all drugs must be stored in a safe place, in a child-proof container. Bathroom cabinets or kitchen cabinets are the safest places as they are out of reach and out of sight of small children. Specific advice on prescribing for children can be obtained from a local pharmacist or the British National Formulary (BNF).
The dosages for children can be calculated on the basis of a percentage chart. Often 'average' doses are used but the prescriber has the absolute responsibility to confirm that the dosages recommended are correct.
The common drugs used for pain control in children are paracetamol BNF and ibuprofen BNF. The potential side-effects and the dosages should be checked with the formulary before prescribing. Aspirin should not be used on children because of the risk of Reye's syndrome. The increase in asthma among children requires that this be considered before ibuprofen is prescribed. Narcotic analgesics such as codeine or morphine can be used on children but only after less powerful analgesics have been shown to be ineffective. As above, the dosage should be checked with the BNF.
Methods of pain control
The different methods of pain control vary from simple behaviour management to full intubational general anaesthesia in a hospital operating theatre. There is a strong relationship between the perception of pain experienced and the degree of anxiety perceived by the patient. Painful procedures cause fear and anxiety; fear and anxiety intensify pain. This circle of cause and effect is central to the management of all patients. Good behaviour management reduces anxiety, which in turn reduces the perceived intensity of pain, which further reduces the experience of anxiety.
Behaviour management have been covered in detail in and local anaesthetic techniques in. The majority of dental procedures on children can be carried out using a combination of these two techniques. This chapter will deal with the methods of sedation and general anaesthesia that are applicable to dental treatment in children. Medical status
The wide variety of medical problems makes it difficult to be precise about the management strategy appropriate for each patient. Detailed descriptions of management of a variety of medical problems appear in a comprehensive book by Scully and Cawson (1998). With regard to sedation, the American Society of Anesthesiologists' (ASA) classification provides an excellent guide to the type of sedation or anaesthesia appropriate to an individual patient's medical and behavioural problems.
The decision as to whether a patient should be treated under general anaesthesia or local anaesthesia, or local anaesthesia with sedation depends on a combination of factors, the most important of which are:
(1) the age of the child;
(2) the degree of surgical trauma involved;
(3) the perceived anxiety and how the patient may (or has) responded to similar levels of surgical trauma;
(4) the complexity of the operative procedure;
(5) the medical status of the child.
There are no hard and fast rules, and every procedure in every child must be assessed individually and the different elements considered in collaboration with the parent and, where appropriate, with the child. For example, the younger the child the greater the likelihood of a need for general anaesthesia. At the other end of the age range it is unlikely that a 15-year old will need general anaesthesia for simple orthodontic extractions, although this might be required for moderately complex surgery, such as exposing and bonding an impacted canine. The degree of trauma involved is also another factor; a single extraction is most likely to be carried out under local anaesthesia, removal of the four first permanent molars is most likely to be carried out under general anaesthesia. Anxiety perceived as excessive, especially after an attempt at treatment under local anaesthesia and sedation, would lead to simple treatment such as conservative dentistry being carried out under a general anaesthetic usually involving endotracheal intubation. Serious medical problems, for example, cystic fibrosis with the associated respiratory problems would justify using sedation instead of general anaesthesia even for more traumatic surgery, such as removal of impacted canines, but it would be appropriate to carry out this sedation in a hospital environment. The degree of intellectual and/or physical impairment in handicapped children would also be a factor to be considered.

General anaesthesia carries with it a finite risk of serious morbidity such as psychological trauma and even death (3 to 4 per million). No child should be submitted to a general anaesthetic without consideration of this potentially devastating outcome. Intermediate between the minimally intrusive techniques of local anaesthesia and the major intrusion of general anaesthesia are the techniques of conscious sedation.