Hypotension After Local Anesthetic Infiltration Into The Oral Submucosa During Oral And Maxillofacial Surgery

摘要

We have noted hypotensive episodes in close association with submucosal infiltration of adrenaline contained in lidocaine. We investigated the effects of adrenaline contained in lidocaine on hemodynamics during oral and maxillofacial surgery under general anesthesia. Sixteen patients with an American Society of Anesthesiologists physical status of I scheduled to undergo sagittal splitting ramus osteotomy were included in this study. The patients comprised 6 men and 10 women with a mean age of 22.3 years and mean weight of 58.5 kg. We measured the patients’ systolic arterial pressure (SAP), mean arterial pressure (MAP), diastolic arterial pressure (DAP), and pulse rate (PR). The patients exhibited a mean 30% decrease in SAP, mean 29% decrease in MAP, mean 33% decrease in DAP, and mean 13% increase in PR. All data were normalized to the values immediately before infiltration and expressed as a relative percentage. The average time from injection to minimum pressure was 88 seconds, and the mean duration of the trough was about 60 seconds. This study suggests that there is an approximately 90-second lag time in hemodynamic changes after local anesthetic injection into the oral submucosa. Local anesthetic infiltration with adrenaline contained in lidocaine elicits temporary but severe hypotension. Introduction Adrenaline contained in lidocaine is widely used in neurosurgery, otorhinolaryngological procedures, dental treatment, and oral and maxillofacial surgery to decrease surgical bleeding [1-3], lessen mucosal congestion, and maintain a clear field of view [4, 5]. In neurosurgery and otorhinolaryngological procedures, local infiltration with adrenaline-containing lidocaine solution elicits temporary but severe hypotension [2, 3, 5]. However, hemodynamic changes has not been known after local anesthetic injection into the oral submucosa for dentists. We here report hypotensive episodes in close association with submucosal infiltration of local anesthetics with adrenaline during general anesthesia. Methods This observational study was approved by the Committee on Clinical Investigation for Human Research (IRB) at Iwate Medical University. Written informed consent was obtained from all patients.We studied 16 patients with an American Society of Anesthesiologists physical status of I who were scheduled to undergo sagittal splitting ramus osteotomy. The patients comprised 6 men and 10 women with a mean age of 22 years and mean weight of 58.5 kg (Table 1). And we could measure 32 cases since the surgeon infiltrated the tissue around both the right and left side of the ascending ramus with a 1 hour time difference (right side: 16 cases, left side 16 cases). All patients underwent intravenous administration of atropine (0.05 mg/kg) and midazolam (0.5 mg/kg) 30 minutes before admittance to the operating room. Anesthesia was induced with a mixture of either thiopental (5 mg/kg) or propofol (2 mg/kg) with fentanyl (50-100 μg) and vecuronium bromide (0.1 mg/kg), then maintained with sevoflurane (1.0%–1.5%) in oxygen (40%). Remifentanyl (0.1-0.2 μg/kg/min) were administered after endotracheal intubation. A catheter was inserted into a dorsal artery of the foot after anesthetic induction to monitor the arterial blood pressure (ABP). The patient’s hemodynamics and respiration were stable at this time. First, the surgeon infiltrated the tissue around the right side of the ascending ramus using 1% lidocaine (1.5 ± 0.4 mg) in combination with 1/100.000 adrenaline (1.5 ± 0.4 μg). Second, the surgeon infiltrated the tissue around the left side of the ascending ramus using same local anesthetic at almost 60 min after infiltrated the tissue around right side of the ascending ramus. The local infiltration was applied at three to five points on the oral mucosal incision, and the infiltration time was controlled at 20 to 30 seconds using the same needle gauge. We measured the ABP via catheter, the systolic arterial pressure (SAP), diastolic arterial pres