Overview of Conscious Sedation in Dentistry
Conscious sedation is a method in which a patient is given medications to feel relaxed but is still conscious, not fully asleep. Patients can still breathe on their own, keep their natural protective reflexes, and respond to speech or light touch. It’s a technique often used in dentistry to help alleviate anxiety. It helps nervous patients or those with special medical needs feel comfortable during treatment, makes it easier for them to cooperate, and allows the dentist to perform complicated procedures without making the patient completely unconscious. On the other hand, general anesthesia puts the patient fully to sleep, and they are unable to respond or breath on their own, requiring respiratory assistance.
Local anesthesia can help control pain in specific areas but doesn’t change levels of consciousness. So, during conscious sedation, local anesthesia is also typically used because conscious sedation by itself doesn’t provide enough pain relief.
Several drugs can be used for conscious sedation, including benzodiazepines, nitrous oxide gas (laughing gas), opioids, ketamine, and propofol. These can be given in different ways, such as through a vein (intravenous), through the nose (intranasal), by mouth (oral), or inhalation. Dentists often use the following combinations:
1. Inhalation sedation using nitrous oxide/oxygen.
2. Oral sedation using a drug called diazepam.
3. Intravenous sedation using a drug called midazolam.
Anatomy and Physiology of Conscious Sedation in Dentistry
Nitrous oxide is a colorless gas that takes effect quickly and is considered very safe. It is often described as being odorless or having a slightly sweet smell. This gas is inhaled and quickly moves from the lungs into your bloodstream through parts of your lungs called alveoli. Your body gets rid of nitrous oxide quickly when you breathe out.
Unlike many other drugs used for conscious sedation (keeping you calm and relaxed while you are awake), nitrous oxide provides slight pain relief and can also alleviate anxiety. Scientists believe that it works by triggering the release of certain natural substances in your body known as enkephalins that help to relieve pain. For relieving anxiety, nitrous oxide is thought to influence a specific receptor in your brain, the GABA receptor, in a similar manner to a group of drugs called benzodiazepines.
Benzodiazepines are a group of drugs with many uses in healthcare. They can help with sleep problems (insomnia), withdrawal from alcohol, anxiety, and seizures. They are often used as sedating agents in dental procedures and for patients in critical care or at the end of life. Benzodiazepines work by activating GABA receptors in our brain which has a calming effect on our body. The properties of these drugs that help reduce anxiety and prevent seizures are also linked to this mechanism. One commonly used benzodiazepine for sedation is midazolam, which has a rapid onset and lasts about 1-2 hours. It’s generally safe when used properly and can cause temporary memory loss.
Another benzodiazepine, diazepam, takes effect within 15 to 60 minutes when taken orally. Because of its effect on anxiety, it can be very useful to take in the hours before a medical or dental procedure as it can help reduce fear and increase the likelihood of the patient going through with their appointment.
Benzodiazepines are considered safe for several reasons. Firstly, there is a big difference between the dose that’s safe and the dose that’s dangerous. Secondly, these drugs are unique because they have an “antidote” or reversal agent called flumazenil, which can reverse their effects if needed, such as in cases of accidental over-sedation or if a patient has difficulty breathing.
Flumazenil works by competing with benzodiazepines to stick to the same receptor in your brain, which in turn reverses the calming effects of the benzodiazepine. It is given by an injection into your veins and usually starts working within 1 to 2 minutes. However, flumazenil does not last as long as midazolam, so patients need to be monitored for up to 2 hours in case the sedating effects of the benzodiazepine return. Some doctors use flumazenil to encourage a quick recovery and speed up discharge times, but this practice isn’t widely endorsed.
Why do People Need Conscious Sedation in Dentistry
Many people feel fearful or anxious about visiting the dentist. This feeling, known as dental anxiety, is the main reason why conscious sedation is often used during dental procedures. Conscious sedation helps the patient relax, making the treatment less distressing for them. It can also ensure that the procedure is safe for individuals suffering from health issues that get worse with stress, like epilepsy or high blood pressure.
Aside from this, sedation is especially beneficial for patients with movement disorders such as Parkinson’s disease. In such cases, uncontrollable movements can make the dental treatment challenging for both the patient and the dentist. Sedation helps manage these involuntary movements, simplifying the treatment process.
Additionally, sedation may be used in more complex surgical dental procedures or for certain age groups of patients, making the dental visit safer and more comfortable for everyone.
When a Person Should Avoid Conscious Sedation in Dentistry
There are certain situations where a pregnant person, someone who is allergic or taking certain medicines, shouldn’t be sedated. It’s also important to be careful when using sedatives on people taking mental health medications as it can make them more deeply relaxed or sleepy than intended. Sedating people with serious illnesses like chronic obstructive pulmonary disease, or those who have multiple health issues, or conditions that block the upper airways (like obesity and sleep apnea) needs extra care because they are at a higher risk of complications.
In these cases, a person might need to be evaluated by an anesthesiologist, a doctor who specializes in pain management during procedures, before getting sedated. This doctor could also administer the sedative at a general hospital for increased safety.
Inhaling sedatives should not be used in people with upper respiratory infections, chronic obstructive pulmonary disease or who have had recent middle ear surgery or infection. A history of illegal drug use can also affect how well the sedative works.
If a person is not fit for conscious sedation, which is when you’re relaxed and drowsy but awake, other options like local anesthesia (which numbs a small part of the body) or general anesthesia (which puts you to sleep) might be considered. The choice would depend on the person’s anxiety level, age and how complex the treatment is going to be.
Equipment used for Conscious Sedation in Dentistry
Before any medical procedure, it’s important to have several things ready and available. These include:
– Monitoring equipment, like a pulse oximeter (a device used to measure the oxygen levels in your blood) and a blood pressure cuff.
– Intravenous (IV) cannulas or masks to deliver nitrous oxygen/oxygen. An IV cannula is a small, flexible tube that can be inserted into a vein to deliver medicines, fluids, or to take blood samples. Nitrous oxygen, also known as laughing gas, is commonly used as an anesthetic during procedures.
– Suction tubing, which helps to remove bodily fluids during a procedure.
– Equipment to deliver oxygen, which is necessary in case of breathlessness or low oxygen levels during a medical procedure.
– A stocked medical emergency trolley, which contains numerous tools and medications needed for emergencies.
– Access to automated external defibrillators, or AEDs. These are devices that can be used to restart the heart in case of cardiac arrest.
– Reversal drugs, which are medications that can counteract the effects of other drugs, particularly anesthetics, if there are any complications.
Who is needed to perform Conscious Sedation in Dentistry?
Before starting any dental treatment that requires sedation, a certain number of healthcare professionals who are trained in sedation techniques must be available. This is usually a dental surgeon and a dental nurse. By doing this, the dentist and the dental assistant can concentrate on the treatment, while a specialist sedation nurse watches over the patient’s overall condition.
All these medical team members receive additional training, earning them an extra qualification. They are also trained in providing basic and immediate life support. This could mean managing medical emergencies or using equipment to help with breathing. This way, they are prepared to handle any unexpected situations and make sure the patient is safe during the treatment.
Preparing for Conscious Sedation in Dentistry
It’s critical for doctors to conduct a complete health check-up, ask about your medical history, and make sure you’re in a good mental state before deciding if you’re fit for certain medical processes. Not only does this keep you safe, but it also helps doctors who might find the procedure more difficult if you’re not able to fully cooperate.
Before performing the procedure, doctors will measure some basic health indicators such as your oxygen levels, blood pressure, heart rate, height, and weight. Your height and weight will be used to determine your BMI (Body Mass Index).
Doctors commonly use a system proposed by the American Society of Anesthesiologists (ASA) to tell whether a patient is fit enough to be given conscious sedation or general anesthesia. Here’s how it works:
* ASA 1: You’re a healthy individual
* ASA 2: You have a mild illness
* ASA 3: You have a severe illness, but it’s not life-threatening
* ASA 4: You have a severe illness that’s a constant threat to your life
Your doctor may also check your airway to see if there’s any chance of complications during the procedure, which might require additional support. One way of doing this is by scoring your airway using the following criteria:
* Class 0: Any part of the flap-like cartilage structure at the root of the tongue, the epiglottis, is visible
* Class I: The back part of the roof of your mouth (soft palate), the dangling structure at the back of your throat (uvula), and the side walls of your throat (pillars) are visible
* Class II: Your soft palate and uvula are visible
* Class III: Only the soft palate and the base of your uvula are visible
* Class IV: Only a section of the roof of your mouth (hard palate) is visible
Your doctor will consider all these factors to make sure you’re receiving the best treatment that is least invasive and tailored to your needs. They’ll think through all the options and make decisions that are in your best interest.
How is Conscious Sedation in Dentistry performed
Inhalation Sedation using Nitrous Oxide/Oxygen
This method is mostly used for children who are nervous about visiting the dentist. Tooth decay is one of the most common health issues and, if not treated, it can result in pain, infections, and the early loss of teeth. This tool enables patients to make through essential dental treatments and avoid these negative outcomes. It also creates a more comfortable environment, which encourages them to return for future appointments. The cooperation of the patient makes it safer and more effective for dentists to perform their treatment.
The procedure starts with the patient breathing 100% oxygen for 2 to 5 minutes. Then nitrous oxide is introduced and the amount gradually increases every two minutes. The maximum amount that can be given is 70%, and many machines will not allow more than this. A typical usage amount is 30-40%. After the procedure, the patient will breathe 100% oxygen for 5 minutes. The dentist must keep an eye on the patient to see when they’ve received enough sedation, and managing the patient’s behavior is crucial for the procedure’s success.
Intravenous Sedation using Midazolam
Patients must have someone with them who can take them home after the appointment, and stay with them for the rest the day and overnight. The person cannot be distracted by other responsibilities, like taking care of children, for example.
When the patient arrives at the dental office, their blood pressure, heart rate, and oxygen levels are checked. These are monitored throughout the procedure to watch out for any changes like decreased breathing or oversedation. An intravenous cannula, which is a thin tube, is then inserted, usually on the back of the hand or the front part of the elbow.
The drug midazolam is typically stored in a 5-mg vial and drawn with a needle. The drug is given slowly so that the patient can be closely watched to reduce any risks of decreased breathing, oversedation, or other complications. An accepted method is to give 2 mg of midazolam slowly, wait for 90 seconds, then give more 1 mg doses at 1-minute intervals until the patient reaches the right level of sedation.
After the treatment, the patient stays in the recovery area until they are ready to leave. This is based on their vital signs and a behavior assessment by a clinician trained in sedation. The person accompanying the patient is reminded of their role in taking care of the patient after discharge. For 24 hours, the patient is not supposed to drive, sign legal documents, or operate machinery.
It’s a good idea to arrange a follow-up visit with the patient if there are any complications or changes to the treatment plan. Because of the drug’s amnesic effects, patients may not remember what they are told, even after they recover from the sedation.
Oral Sedation using Diazepam
The patient takes either 5 or 10 mg of diazepam one to two hours before the appointment, depending on the dentist’s instruction. The patient must have someone with them and cannot drive after the procedure. Vital signs should be recorded before and after the treatment. The patient must be alert enough to respond to verbal commands during the procedure. While this method is simpler, less expensive, and doesn’t require a lot of equipment, it has a less predictable effect and results in a milder level of sedation compared to midazolam.
Possible Complications of Conscious Sedation in Dentistry
Breathing in a gas mixture of Nitrous Oxide and Oxygen for sedation during a medical procedure is generally safe, with severe side effects being quite rare. However, some people might feel sick or even throw up. They might also experience laryngospasm, which is tightening of the voice box muscles that can briefly disrupt breathing. Another infrequent side effect is diffusion hypoxia; this happens when inhaling a high amount of oxygen results in less oxygen reaching your body tissues. Also, nitrous oxide can occasionally affect how vitamin B12 works in your body.
With midazolam, which is given through a vein for sedation, some potential side effects could occur. You might feel sick, throw up, or have temporary low oxygen levels in your blood, known as transient desaturations. Some people might have a strange, opposite response to the medicine, known as paradoxical reactions, which might make you feel restless or excited instead of calm. Others might experience dizziness, sleepiness, hiccup, hallucinations, or slowed down breathing.
Oral sedation with diazepam (a pill you swallow) has similar potential side effects to midazolam since they’re in the same drug category. These side effects are less likely to occur since the drug is taken orally (by mouth), not directly introduced into your bloodstream like IV midazolam.
What Else Should I Know About Conscious Sedation in Dentistry?
Dental anxiety, a fear of going to the dentist, is a common issue affecting about 1 in 5 people, both children and adults. This fear can lead to people avoiding dental appointments, which can harm their oral health. A more severe form of this anxiety affects about 5% of all people. When traditional methods to lessen this anxiety don’t work, a technique known as conscious sedation can be very helpful.
In conscious sedation, medications are carefully adjusted to create the right balance. This ensures the safety of the dental procedure, allows the dentist to perform the necessary treatment, and helps reduce the patient’s anxiety.
It’s crucial to know that even when sedative drugs are used, adequate local anesthesia (numbing medication) must still be given. Using more sedation isn’t a substitute for proper local anesthesia and can potentially lead to complications. It’s safer to have conscious sedation under the supervision of a trained professional, as it can help avoid the potential issues that can come with general anesthesia (being put completely to sleep for a procedure). This makes conscious sedation a safer option that also helps to reduce waiting times for procedures.