INCIDENTS ACCIDENTS OF LOCOREGIONAL ANESTHESIA IN DENTAL SURGERY
INTRODUCTION
Local anesthesia, widely used in odontostomatology, is often considered a harmless procedure. However, this method of anesthesia can cause:
– minor local incidents (broken needles)
– general accidents (vagal discomfort)
As for these accidents, we must not neglect the role played in their occurrence by:
– the land,
-the product used, its associations.
Our role is therefore to be fully aware of these complications for the
– prevent and treat them
Local anesthetics: substances placed in contact with nerve fibers temporarily block nerve conduction through their membrane-stabilizing action.
Responsible for a sensory and possibly motor block, under normal conditions of use.
They do not alter consciousness, ventilation or hemodynamic status (≠AG).
However, this technique, made falsely reassuring by the preservation of consciousness, is not without risks which can be life-threatening.
LOCAL ACCIDENTS
I-TECHNICAL PROBLEMS
Needle fractures, needle inhalations or swallowing, fortunately rare complications.
In the case of needle fractures during AL often the needle is easily removed.
This is not always the case during a deep truncal A.
A precise radiographic assessment must locate the needle.
Its removal will require careful dissection, plane by plane, and will sometimes prove very difficult.
It is important to preserve the broken needle portion and replace it with an identical new needle.
The patient should be informed of this incident and given ATBs
II-PAINFUL INJECTION
This is the case when the liquid is cold and the injection is rapid .
There is also a particular pain and resistance to anesthesia when the tissues are inflamed .
Encountering nerve endings at specific points can also trigger a painful reaction.
III-HEMORRHAGIC ACCIDENTS Two cases may arise:
– Normal hemostasis assessment : Hematoma at the injection site, its resorption is rapid;
Trauma during truncal anesthesia
eg in the mandible (inferior alveolar artery): bleeding in jerks, which may continue for the rest of the operation.
– Hematological assessment is disturbed , it is necessary to avoid
Regional or local anesthesia in loose tissues (floor of mouth).
Significant hematomas may occur, causing compression (particularly of the respiratory tract) or infection.
-Hemorrhagic accidents . What should be done?
Treatment should first be preventive with prior questioning (patient is not on anticoagulants or antiplatelet drugs).
In case of anticoagulant treatment: a hemostasis assessment, TP, INR, and a platelet count.
If the patient is taking Aspirin or Plavix, it is necessary to stop taking them for 5 to 10 days, with the agreement of the prescribing physician.
Taking anticoagulants or antiplatelet drugs will cause chronic bleeding that does not stop, and long-term compression is then required.
IV-NERVOUS TRAUMA
Rare during nerve block anesthesia, as the nerve leaks in front of the needle.
It is different when it is enclosed in the bony canal (anesthesia at the mental foramen).
Other neurological complications may occur due to diffusion of the anesthetic fluid into neighboring compartments during truncal anesthesia.
Facial paralysis and eye problems may occur.
– oculomotor paralysis;
– an alteration of visual perception;
– eyelid ptosis;
– dizziness.
These accidents are short-lived and leave no after-effects.
V-INFECTIOUS ACCIDENTS
Impact site infections are rare and occur during injections into infected terrain.
VI-ALVEOLITIS
It appears to be more common after local anesthesia than after general anesthesia.
The role of vasoconstrictors has been questioned.
The pathogenesis of alveolitis is so complex that it is difficult to draw conclusions.
VII-MUCOSAL NECROSIS
Rare cases exist, especially caused by injections that are too sudden at the palatal level.
VIII-NAUSEA, SENSATIONS OF ASPHYXIA
These incidents occur when the anesthesia reaches the soft palate.
IX-ANESTHESIZED SOFT TISSUE INJURIES
The absence of sensitivity of the lip after local or locoregional anesthesia requires protection of soft tissues from lesions or burns caused by direct contact with a handpiece.
Once the procedure is complete, the patient must be warned of the risks of bites and burns (cigarettes) as long as the insensitivity persists.
a) A puncture during anesthesia of the inferior alveolar nerve
1 Clinical signs – Partial or complete anesthesia of the nerve territory concerned
– Areas of hypoanesthesia or paresthesia
2 After-effects
– Wounds on the lower lip
– Burns from a cigarette
– Difficulty speaking
– Tingling and burning sensation in the subcommissural region
– Continuous, sharp and radiating pain…
b) Lingual nerve
1Clinical signs – Anesthesia, hypoesthesia or paresthesia of the affected hemi-tongue
– Deficit in taste sensitivity
2 Consequences
– Biting of the edge of the tongue on the affected side
d) Treatment of nerve damage
– Vitamin B therapy
– Corticosteroid therapy
– Electrotherapy
– In case of failure and resistance: Tegretol, Rivotril
GENERAL ACCIDENTS
I-VAGAL DISCOMFORT OR LIPOTHYMIA
This is bradycardia associated with profuse sweating, pallor, polypnea and even loss of consciousness (it is very brief).
Occurs in emotional, tired, anxious subjects, favored by the sitting position.
Most often, it is triggered from the start of the injection.
A gradual onset; the subject feels the discomfort coming. More or less associated with it
– dizziness;
– feelings of hot flashes;
– tinnitus;
– visual disturbances;
– and a feeling of heaviness in all his limbs.
· Prevention
Vasovagal discomfort can be prevented by giving the patient a sedative premedication administered 2 hours before local anesthesia.
· Treatment
The patient is laid down and his legs are raised above his head for thirty seconds, which facilitates cerebral irrigation.
He recolors and comes back to himself.
Atropine injection is very exceptionally useful.
Be careful of the risk of falling.
If the patient is weakened, we keep him in the waiting room for a while.
II-CARDIORESPIRATORY SYNCOPE
This is a very short cardiorespiratory arrest, with sudden loss of consciousness.
This is a vagal reaction occurring after the injection.
The patient is motionless, pale, inert.
The pulse is not perceptible and there is no breathing.
The evolution is variable:
– favorable in 1 minute;
– or worsening.
INCIDENTS ACCIDENTS OF LOCOREGIONAL ANESTHESIA IN DENTAL SURGERY
III- CARDIOCIRCULATORY DISTRESS
It can succeed:
– fainting; syncope;
– a convulsive crisis;
– or an allergic accident.
The pathogenesis is variously interpreted:
– vagal reaction;
– direct toxicity of the anesthetic product on the heart.
This toxicity aggravates a heart rhythm disorder. At high concentrations, the anesthetic can cause a drop in cardiac output and a fall in blood pressure.
The diagnosis is made in front of:
– cardiovascular signs: rapid, pounding pulse; drop in blood pressure
– respiratory signs: rapid, shallow breathing; cyanosis of the lips, earlobe and nail bed;
– neurological signs: general malaise; agitation; then coma.
Without effective treatment, the progression of this condition is circulatory arrest.
The risk of heart attack can be activated by the surgical procedure or the use of our products.
In a patient with cardiovascular risk factors, who has angina or is being treated with Trinitrine, the use of vasoconstrictors, such as those present in certain anesthetics, should be avoided.
IV-hypoglycemic crisis
When fasting, a patient becomes stressed. He will secrete noradrenaline and consume his glucose. He then finds himself in hypoglycemia. He trembles, feels bad. He is then given a glass of water in which three sugars have been dissolved. In the event of loss of consciousness, emergency services are called.
V-An epileptic seizure can be triggered by stress
Hence the importance of questioning to find antecedents.
There are several types of epilepsy. The most caricatured is “grand mal”: the patient begins to tremble.
The onset of the sudden crisis, without prodrome:
– loss of consciousness;
– stiffening of the body;
– tilting the head backwards;
– eyes rolled back;
– and the appearance of generalized convulsive movements.
The crisis is generally brief but can recur in the absence of treatment with risk of collapse.
V-CONVULSIVE CRISIS
It is most often due to:
– to an overdose or intravascular injection;
– or occurs in subjects with altered hepatic metabolism (e.g. cirrhotics), in subjects with altered hepatic blood flow (heart failure, beta-blockers, cimetidine).
CAT:
The patient is placed on the floor in the lateral safety position. Check that there is nothing left in the mouth and protect the tongue, which is held in place.
A benzodiazepine injection will calm the attack.
VI-THE TETANIUM CRISIS
In fact, the patient stiffens, his limbs twist.
If it is a simple tetany, it can be regulated by controlling ventilation. He is asked to inhale while counting 1-2 and to exhale while counting 1-2-3. Otherwise, he can also be advised to completely block his breathing, for as long as possible.
If the crisis is not resolved, emergency services are contacted.
VII-ASTHMA ATTACK
After the injection, we note:
– breathing difficulties;
– retrosternal chest pain;
– anguish ;
– cyanosis;
– hustle.
Apart from basic treatment, the treatment of the crisis primarily involves beta-stimulant drugs in aerosol or spray form.
The course of an asthma attack is favorable under treatment, otherwise it can lead to acute respiratory distress.
VIII-COMPLICATIONS RELATED TO THE USE OF LOCAL ANESTHETICS
The adverse effects of AL are mainly:
– Neurotoxic and/or cardiotoxic effects
– Anaphylactic or anaphylactoid reactions have been reported more rarely.
They are wrongly invoked because of the lack of knowledge of the pharmacological properties of local anesthetics and the mechanism of the accidents observed.
Most accidents come from:
– either an overdose of anesthetic or vasoconstrictor;
– or vagal discomfort.
INCIDENTS ACCIDENTS OF LOCOREGIONAL ANESTHESIA IN DENTAL SURGERY
a- Allergic reactions
This is an immediate hypersensitivity to a product, they are essentially caused by aminoesters (preservatives).
The reported symptoms are classic: urticarial rash, pruritus, bronchospasm, Quincke’s edema and anaphylactic shock.
Most of these can be prevented by using preservative-free solutions.
Frequently, incidents occurring in dental surgery are reported to be due to an allergy to LA. In all likelihood, these are more likely to be vagal-type discomforts or even intravascular passage of LA and/or adrenaline.
If in doubt, skin sensitivity tests may be suggested.
Allergic accidents are distinguished from vagal discomfort by two points:
– its onset time, at least 3 to 5 minutes after the injection, is longer than that of vagal discomfort which sometimes occurs at the very moment of the injection.
– it has cutaneous signs such as pruritus
Anaphylactic accidents to AL can be considered non-existent.
Confusion between acute allergic accident and certain local traumatic-type edemas is frequently observed.
Preservatives such as sulfites can cause anaphylactic-like accidents and asthma attacks.
b. Toxicity of local anesthetics
This is the most serious complication, sometimes fatal:
– at a concentration of 2 mg/mL, minor manifestations of toxicity appear: paresthesia of the extremities;
– beyond 20 to 25 mg/mL, respiratory arrest and then cardiac arrest are possible.
The toxicity of aminoesters appears to be related to the preservative.
Used in high concentrations, amino-amide type ALs have a myotoxic and neurotoxic effect.
– the main factor in fatal accidents is the injection too rapid or too quickly repeated of a local anaesthetic at high concentration (2% instead of 0.5 or 1%) during a vascular breach;
– besides this technical error, overdose accidents are linked to metabolism problems ;
– finally, it is appropriate to recall the considerable interest of the association with a vasoconstrictor. The latter:
– reduces by almost half the amount of anesthetic needed to produce the same anesthesia;
– keeps the anesthetic in place, preventing it from suddenly passing into the general circulation;
– reduces local bleeding.
1. Cardiotoxic accidents
Cardiotoxicity is dose-dependent: the more powerful a local anesthetic, the more toxic it is.
Electrically. Bupivacaine is responsible for bradycardia, leading to asystole, but also for atrioventricular and intraventricular blocks. Alteration of conduction velocity can generate conduction blocks, causing supraventricular or ventricular tachycardia or even ventricular fibrillation.
On the electrophysiological level, the most toxic molecules are bupivacaine and etidocaine, while lidocaine and mepivacaine have little effect. The “frequency-dependent” effects are much more marked with bupivacaine and etidocaine.
In contrast, the blood pressure drop is much greater with etidocaine and lidocaine than with mepivacaine and bupivacaine.
Many factors can aggravate the cardiac toxicity of LA such as hypoxia, hypercapnia, acidosis, hyperkalemia, hyponatremia and hypothermia
Furthermore, AL neurotoxicity directly influences cardiotoxicity
2. Neurotoxic accidents
The action of ALs on the central nervous system and the expression of neurological toxicity is a function of the cerebral concentration of ALs and, above all, of the speed of increase of this concentration.
Lidocaine has an anticonvulsant effect at plasma levels between 0.5 and 4 μg/mL and a proconvulsant effect at levels around 10 μg/mL.
All ALs, esters and amides, can induce convulsions.
In unmedicated patients, the first clinical signs are drowsiness or a feeling of intoxication, headaches, tinnitus, logorrhea, a metallic taste in the mouth and perioral paresthesia.
This symptomatology precedes the generalized convulsive crisis.
It can be masked by premedication or sedation.
In the absence of treatment, coma, respiratory depression and, for higher levels, myocardial depression then appear.
It is therefore necessary from the outset
-oxygenate: If hypoxia persists, the patient must be intubated.
– Stop convulsions: thiopental and benzodiazepines (diazepam, midazolam)
FIELD-RELATED COMPLICATIONS
Elderly subject
He has diminished kidney, respiratory, cardiac and liver functions,
which means that the dosage must be reduced by a third at 70 years of age and by half at 80 years of age.
Pregnancy
Local anesthesia in pregnant women can generally be performed without risk, provided that the pregnancy is progressing normally and that the doses of anesthetic used are moderate.
– Articaine is the least toxic anesthetic molecule during pregnancy.
– Adrenaline will only be used locally and at low concentrations.
There is no teratogenicity associated with local anesthetics.
BASIC RECOMMENDATIONS FOR THE USE OF LOCAL ANESTHETICS
– Whenever possible, give the least concentrated solution containing a vasoconstrictor .
– Inject the lukewarm solution slowly and perform aspiration to check that the injection is not intravascular.
– Monitor the patient during the injection and for 30 minutes afterward to detect any warning signs early.
– If there are any warning signs, stop the injection and monitor the three main functions : neurological, respiratory and cardiovascular.
– In addition, the patient’s stress must be considered as a risk factor, and reduced through dialogue.
CONCLUSION
ALR is of major interest in ODF. However, the risks are not zero and the occurrence of an accident will have serious medico-legal consequences if basic precautions are not taken.
Most toxic accidents can be prevented by judicious choice of AL, rigorous technique and close per-anaesthetic monitoring of the patient.
The benefit of having a functional standard emergency cart with validated protocols.
INCIDENTS ACCIDENTS OF LOCOREGIONAL ANESTHESIA IN DENTAL SURGERY
Untreated cavities can reach the nerve of the tooth.
Porcelain veneers restore a bright smile.
Misaligned teeth can cause headaches.
Preventative dental care avoids costly treatments.
Baby teeth serve as a guide for permanent teeth.
Fluoride mouthwash strengthens tooth enamel.
An annual checkup helps monitor oral health.