Abstract
To offer individualized dental treatment to certain patients who cannot tolerate dental treatment, sedation or general anesthesia is required. The needs could be either medical, mental, or psychological. The most common indications for sedation or general anesthesia are lack of cooperation, multiple morbidities, and pediatric autism. In adults, cognitive impairment and multiple morbidities are most commonly encountered indications. Because of suboptimal home care, incomplete medical history, poor preoperative management, lack of cooperation, and developmental abnormalities, it is a challenge to prepare anesthesia for patients with special needs. The American Society of Anesthesiology (ASA) has proposed guidelines for office-based anesthesia for ambulatory surgery. In patients with ASA physical status IV and V, sedation or general anesthesia for treatment in the dental office is not recommended. The distinction between sedation levels and general anesthesia is not clear. If intravenous general anesthesia without tracheal intubation is chosen for dental procedures, full cooperation between the dentist, dental assistant, and anesthesiologist is needed. Teamwork between the dentist and healthcare provider is key to achieve safe and successful dental treatment under sedation or general anesthesia in the patient with special needs.
Keywords
anesthesia, dental; dental care for disabled; sedation;
1. Introduction
Special needs is terminology used in clinical diagnostic and functional development to describe individuals who require assistance for disabilities that may be medical, mental, or psychological. These patients have been called disabled, impaired, or handicapped. The definition of disability is any restriction or lack of ability to perform an activity in a normal way or within the manner considered normal for a human being, whereas impairment refers to any loss or abnormality in physiologic as well as anatomic structural function. Handicapped is defined as the disadvantage of a given individual, resulting from an impairment of disability, that limits or prevents the fulfillment of expectation or a role that is normal for an individual. These words might imply a sense of despise, and the medical treatments were considered to be mercy on the inferiors. Therefore, these terms have been replaced with a more neutral term special need. Every person has an equal right to medical care. As medical care providers, we should individualize our treatment and service and ensure delivery of optimal medical resources for individuals with special needs.
The health condition and functional status in patients with special needs are interrelated.1 Dental caries is the most common oral problem in children in most of the developing countries. There is a higher incidence of dental caries in patients with special needs because of inadequate plaque removal due to motor, sensory, or intellectual disabilities in these patients. Malocclusion also affects oral health and increases caries prevalence.2 For example, patients with Down syndrome tend to have more dental anomalies, poorer periodontal health, and fewer dental visits than age- and sex-matched control groups.3, 4 The most common reasons for not receiving regular dental care for dental conditions are unawareness of the dental condition and the importance of dental visits.4 Until 2010, there were 107,000 special-needs patients in Taiwan, and the number is increasing. Oral health education and the interventions of sedation and general anesthesia should be instituted for management of dental health conditions.
2. Dental fear and phobia
Sedation and general anesthesia can help those who are unable to tolerate the pain of dental treatment, such as individuals who experience anxiety and fear during dental visits, those with cognitive impairment or motor dysfunction, children, and those unable to tolerate physical stress. Studies of dental fear and anxiety showed that the prevalence of dentophobia was approximately 10% in the general population.5 Dentophobic patients usually seek dental care with reluctance only when they have symptomatic dental conditions such as severe toothache or dental abscess. Thus, these patients are more likely to delay treatment, resulting in more extensive or severe conditions. This vicious cycle leads to the continuation or exacerbation of existing dental fear, causing a cycle of avoidance.6 In particular, women are more inclined to have dental fear. Patients aged from 40 to 64 years old have the highest prevalence of dental fear, and people older than 80 years old have the lowest prevalence.7
3. Characteristics of patients with special needs
Proper preanesthetic evaluation and preparation are important. Mild anesthetic complications do occur in people with special needs.8 However, suboptimal home care, incomplete medical history, poor preoperative management, lack of cooperation, and developmental abnormalities in people with special needs make preanesthetic preparation more difficult. Full cooperation between caretaker and dentist is important.
The most common indications for dental anesthesia in patients younger than 14 years are lack of cooperation, multiple morbidities, and autism. In our hospital, the main reasons for anesthesia in adults with special needs are cognitive impairment and multiple morbidities. Cognitive impairment defines patients who are developmentally delayed and those who have dementia. Appropriate sedation or general anesthesia could ease the process of dental treatment in patients who are unable to cooperate during the dental visit. Motor dysfunction includes parkinsonism, cerebral palsy, and other diseases that cause uncontrolled tremor. Sedation or general anesthesia is sometimes required so that these patients can keep their mouth open for the treatment. Children can be considered another special needs population. Children younger than 3 years are usually uncooperative with their dentists, resulting in the use of papoose boards and physical restraints during the dental visit. For lengthy and extensive treatment, sedation and general anesthesia could ease the tension and fighting among children, parents, and dentists. In addition, children with congenital conditions such as congenital heart disease and hydrocephalus may complicate the anesthetic decision and management.9 For those who have severe cardiovascular disease or other systemic disease, stress-induced sympathetic tone activation may be harmful due to increased heart rate and systemic vascular resistance. Proper sedation and general anesthesia could be considered to tamper the stress effects.
3.1. Down syndrome
The incidence of Down syndrome, characterized by an anomaly of chromosome 21, is estimated to be per 800 to 1000 births.10 Children with this condition have characteristic features such as low-set ears, small teeth, a flattened nose, stunted growth, atypical fingerprints, and hypotonia. They are developmentally delayed and constitute most of the dental patients with special needs. Generally, these patients are more obese, and vascular access may be difficult in young Down syndrome patients.11 On the other hand, these patients have large tonsils and adenoids, a small subglottic area, prolapsed epiglottis, and a large tongue.12 Airway management might be difficult because of the anatomic abnormalities. Advanced airway device and video-assisted intubation devices should be available for tracheal intubation. For those in whom ventilation is difficult, sedation is not recommended. Approximately 10% to 40% of children with Down syndrome have atlantoaxial instability.13 Unnecessary head extension during dental treatment should be avoided to prevent subluxation in these patients. Approximately 40% of patients with Down syndrome have congenital heart anomalies.14 Consultation with a cardiologist is needed before anesthesia, especially for those with complex heart disease. Due to complex craniofacial and cardiovascular abnormalities, patients with Down syndrome tend to have increased anesthetic complications, such as bradycardia on anesthetic induction, airway obstruction, and postintubation croup.15, 16 Anesthesiologists should be aware of these potential problems and be prepared for counteraction.
3.2. Cerebral palsy
Cerebral palsy comprises a group of nonprogressive motor conditions manifested by physical disabilities in development due to brain injuries during the antenatal, perinatal, or postnatal period.17 The prevalence is approximately two per 1000 live births.18, 19, 20 Patients with cerebral palsy tend to have complicated dental problems due to lack of lip seal, higher malocclusion rate, temporomandibular disorder, difficulty swallowing, and associated malnutrition and aspiration pneumonia.21, 22, 23, 24 Their oral hygiene status is also the burden of the caregivers.25 Patients with cerebral palsy usually have additional disability attributable to central nervous system damage, such as cognitive impairment, visual or hearing problems, seizures, and communication and behavioral disturbances, as well as the chronic systemic problems resulting from their disease. Severity of cerebral palsy is often associated with postoperative complications. Airway maintenance during anesthetic induction may be complicated by excessive secretions. Tracheal intubation should be performed if this is a concern or if there is a history of gastroesophageal reflux. Children with cerebral palsy are often physically small for their age. Tracheal tube size selection should be based on the patients' age. Careful positioning is of paramount importance in the child with spastic cerebral palsy to forestall nerve or muscle damage. Fixed contractures may add difficulty to positioning. The responses to anesthetic agents may also differ. There may be resistance to nondepolarizing muscle relaxants.17 There appears to be a close correlation between severity of preoperative cerebral palsy and postoperative complications. The risk of perioperative adverse events was 63.1%, mostly of hypothermia and hypotension. Factors associated with increased risk included American Society of Anesthesiologists (ASA) physical status score of 2 or higher, history of seizures, upper airway hypotonia, general surgery procedures, and adulthood.26
3.3. Epilepsy
Epilepsy is a common chronic neurologic disease resulting from abnormal hypersynchronous neuronal activity in the brain.27 It is important for anesthesiologists to identify the type, frequency, severity, and triggering factors of epilepsy. Anesthesiologists must understand the proconvulsant and anticonvulsant properties of drugs used in anesthesia and minimize the risk of seizure activity in the intraoperative and postoperative periods. Because antiepileptic drugs could produce sedation or inhibit metabolizing enzymes, the dosages of general anesthetic should be reduced considerably if they are concomitantly used. Patients partaking of a ketogenic diet must be evaluated before anesthesia. A ketogenic diet is high in fat and low in protein and carbohydrates. Maintaining therapeutic ketosis and modifying the acid-base balance are particularly important to prevent seizures in patients on a ketogenic diet. Propofol, sevoflurane, and acetated Ringer solution have been reported to be safely used in children on a ketogenic diet.28, 29 Due to the risk of metabolic acidosis, serum pH or bicarbonate levels should be monitored in cases with longer course.30
3.4. Autism
Autism is a developmental disorder that is usually diagnosed before age 3 years. Children with autism have characteristic symptoms such as impaired social interactions, verbal and nonverbal communication deficiencies, limited activities and disinterest, repetitive behaviors, and difficult responses to changes in routine. Some of them have other behavioral disturbances such as self-mutilation, aggression, and psychiatric symptoms. Some autistic patients take medications for behavior control to help them integrate effectively in the educational and rehabilitative process.31 Early communication with the patient's families, flexibility to individualize the anesthetic plan, and awareness of possible interaction of behavior medications and anesthetics are important in management of these patients.32
4. Environment for office-based dental anesthesia
The ASA has developed guidelines for office-based anesthesia and ambulatory surgery. Office-based facilities, although incomparable with those of the hospital, should comply with all federal, state, and local rules or regulations. Environmentally, there should be a reliable source of oxygen, suction, resuscitation equipment, and available emergency drugs. There should be an appropriate anesthesia apparatus or equipment with necessary monitoring. Monitoring resources should include the competent responsible personnel, noninvasive blood pressure monitor, pulse oximeter, electrocardiography, and stethoscope and capnograph.33 If anesthesia is to be provided for pediatric patients, the required equipment should be suitable for children of all ages. Sufficient electrical outlets and adequate illumination are necessary. There should be enough spaces for necessary equipment and the serving medical staff. For life-threatening situations, an emergency cart, defibrillator, and advanced airway management tool should be on hand. The anesthesiologist should be present during the intraoperative period until the patient has been safely discharged from anesthetic care.34
5. Patient selection in outpatient setting
Complications (mainly mild or moderate) associated with administration of anesthesia occur at approximately 20%. Airway obstruction and nausea and vomiting are the most common complications. ASA classification, anesthetic technique, preexisting medical condition, and dental procedures are all contributable factors.35 Patients with ASA class IV and V are not recommended for sedation or general anesthesia in the dental office. Patients with ASA class III should be evaluated by the anesthesiologist responsible for the decision.
6. Depth of anesthesia
Sedation and general anesthesia can be graded as mild, moderate, and deep, and by different levels of consciousness, ventilation status, and cardiovascular function. Patients in deep sedation are not easily arousable, but could be responsive to painful stimulation. Their ventilation may not be adequate and assisted respiration is needed with patent airway. There is no clear boundary between the levels of sedation; with the same dosage of drug, a patient might cross from moderate sedation to deep sedation. There is the likelihood of adverse events after being subjected to sedation. It is of paramount importance to watch patients' airway and ventilation after sedative administration, and discharge criteria should be observed strictly.36 Even with oral anxiolytic agents, which have a wide margin of safety in adults, serious complications have been reported with conscious sedation, especially in young children. Most serious adverse events are related to potentially avoidable respiratory complications.37
7. Nonintubated general anesthesia
If intravenous general anesthesia without tracheal intubation is chosen for dental anesthesia, it is required to keep excellent cooperation between the dentist, dental assistant, and anesthesiologist. Because the airway is not secured by placement of the endotracheal tube, aspiration, laryngospasm, and hypoxia could occur with disappointing results. It is suggested to have a dental treatment plan in place in advance to forestall complications. In addition, patients in whom perceptive difficult ventilation and difficult laryngeal mask insertion are evident are not good candidates for nonintubated general anesthesia. Patients should strictly follow fasting rules to decrease the risk of aspiration. Effective local anesthesia helps maintain an acceptable anesthetic level. A throat pack and efficient suction are important to avoid flooding of the mouth by rinsing water and facilitate removal of secretion or debris. Delivery devices such as infusion pumps for drugs such as propofol, when coupled with computers, can help regulate the infusion rate and control the sedative effect. Bispectral index-guided target-controlled infusion of propofol has been used for patients with intellectual disabilities.38 Due to complex physical condition and various medication commonly used for patients with special needs, the use of target- controlled infusion needs more evidence of its efficacy and safety. Patient-controlled sedation might be the trend for optimal conscious sedation in the future.39
8. Conclusion
Anesthesia provides optimal conditions for dental treatment for special needs. Additional care should be undertaken based on patients' special physical problems, psychological needs, and social support. An individualized anesthetic plan and management and teamwork between the dentist and anesthesiologist are key points to materialize safe, successful, and satisfactory anesthetic conduct for these patients.
Disclosure
The authors have no financial interests related to the material in the manuscript.