Local anesthesia may induce systemic complications leading to parasympathetic activity leading to bradycardia and hypotension. We report a case of a 50-year-old man undergoing dental surgery under general anesthesia who experienced severe bradycardia and hypotension after local anesthesia infiltration. Concerns regarding the utilization of a relatively large lumen injection needle for local anesthesia during general anesthesia are discussed.
Local anesthesia oral mucosal infiltrations have the potential to induced systemic complications [
A 50-year-old man who weighed 56.1 kg was scheduled to undergo extraction of his right mandibular wisdom tooth and excision of a tumor. He had no past medical history and had not been prescribed any drugs. His preoperative electrocardiogram was within normal limits and showed a normal sinus rhythm, a PR interval of 0.162 seconds and a QT interval of 0.387 seconds. All laboratory values were within the normal range, and the patient had no known drug allergies.
Atropine (0.2 mg) and midazolam (3.0 mg) were intravenously administered in the operating room. Anesthesia was induced with propofol (110 mg), fentanyl (50
The patient’s HR slowly decreased from 62 bpm to 36 bpm within 2 minutes. The sinus rhythm was observed but there was not bigeminy or atrial flutter on ECG. His BP remained approximately 80/43 mm Hg and his mean BP was 74 mm Hg. Atropine sulfate (0.3 mg) was administered intravenously, and his HR was restored to 67 bpm within 1 min; at this time, systolic BP was 116 mm Hg, diastolic BP was 75 mm Hg, mean BP was 89 mm Hg, and the SpO2 and ST-T segment were unchanged. End-tidal CO2 increased from 39 to 46 mm Hg. The patient’s hemodynamics were stable for the remainder of the procedure: HR was 59–64 bpm, systolic BP was 82–103 mm Hg, diastolic BP was 41–58 mm Hg, and SpO2 was 100%. The surgery was successfully completed approximately 30 minutes after the episode of bradycardia.
Severe bradycardia is associated with the infiltration of local anesthetic into the oral mucosa under general anesthesia. Anxiety, fear, and pain associated with clinical treatment can trigger an intense parasympathetic state leading to bradycardia and hypotension in an awake or sedated patient [
If the patient is unconscious under general anesthesia, he should not feel pain. General anesthetics can inhibit sensory tract, cerebral cortex, and neurotransmission in spinal but there is a peripheral activation of nociceptors under general anesthesia; therefore, it is a possibility that an intense noxious stimulus indicating a peripheral activation of nociceptors associated with infiltration into oral submucosa can trigger an intense parasympathetic state leading to bradycardia.
The oral and maxillofacial surgeons typically need to infiltrate local anesthetic into the oral mucosa to decrease surgical bleeding, lessen mucosal congestion, and maintain a clear field of view. When we think about the effects of adrenaline contained lidocaine, we have usually experienced hypotension by induced adrenaline and the increase in HR. The cause of this increase in HR mainly involves a baroreceptor reflex that decreases the blood pressure and gently stimulates
Regarding the possible influence of the general anesthesia pharmacotherapeutics as such atropine, midazolam, propofol, fentanyl, rocuronium bromide, sevoflurane and remifentanil, and local anesthetic lidocaine, we do not know clearly whether these drugs could be the cause or even partially influence the bradycardia. There is possibility that all these drugs have the cause or even partially influence the bradycardia but immediately after the infiltration of local anesthetic into the oral mucosa, we think that this bradycardia is induced by an intense noxious stimulus.
It is our opinion that infiltration of local anesthetic into oral mucosa with a large needle and strong pressure by surgeon’s hand should be avoided. During dental treatments, the sting from the needle is occasionally associated with systemic complications, such as the vasovagal reflex, hyperventilation syndrome, ischemic heart disease, and arrhythmias [
In conclusion, severe bradycardia is associated with the infiltration of local anesthetic into the oral mucosa under general anesthesia and the infiltration of local anesthetic into oral mucosa with a large needle and strong pressure by surgeon’s hand should be avoided. It is prudent to recognize the possibility of this complication when a needle is introduced into the oral submucosa during general anesthesia.
Written consent for publication was obtained from the patient.
The authors declare that there is no conflict of interests regarding the publication of this paper.