Anesthesia Complications of Benzodiazepine Use for Adolescents Receiving Extraction of Third-Molars

The most common anesthetic regimen for third-molar extraction in the ambulatory setting is comprised of diazepam or midazolam alone or in combination with an opioid, or other anesthetics such as propofol, methohexital, or ketamine.  To date, few prospective studies have been published on anesthetic complications in oral and maxillofacial surgery (OMS), and even less is known on the effects of dosing adolescents with benzodiazepines.  The purpose of this study is to evaluate the safety of using midazolam and/or diazepam during third-molar extraction, and whether any differences in perioperative complications exist when using the two benzodiazepines.

A prospective cohort study was conducted with data collected through the Oral and Maxillofacial Surgery Outcomes System commissioned by the American Association of Oral Maxillofacial Surgeons.  The study cohort included adolescent patients (less than 21 years of age) who underwent third-molar extraction procedures in the ambulatory setting between January 2001 and December 2007.  The study cohort was divided into three groups- patients who received diazepam, midazolam, or a combination of both diazepam and midazolam.  The primary predictor variable was type of benzodiazepine used.  The outcome of interest was adverse complication(s) resulting from anesthesia.  Multivariable logistic regression was then applied to measure the effect benzodiazepine type had on adverse complication.

A total of 18,090 subjects met inclusion criteria for the study cohort; 54.6% of subjects were males.  The mean age was 17.2 +/- 2.3 years old.  Among the study cohort, 4,213 (23.3%) subjects were in the diazepam group, 13,451 (74.4%) were in the midazolam group, and 426 subjects (2.4%) received a combination of diazepam and midazolam. Over 90% of subjects in each group had an ASA risk status of I/ II.  The midazolam group had a significantly higher anxiety score of 2.4 +/- 0.9 (P< 0.001).

A total of 194 perioperative complications (1.1%) were experienced among subjects within the study cohort.  Subjects in the diazepam and combination group each had a complication rate of 1.4%, while subjects in the midazolam group had a complication rate of 1.0% (P= 0.027).  Within the diazepam group, the most common complications was vomiting without aspiration during recovery, followed by peripheral vascular injury (0.5% and 0.3%, respectively).  Within the midazolam group, the most common complication was vomiting without aspiration during recovery, followed by syncope (0.2% for both).  For the combination group, peripheral vascular injury and respiratory arrest were the two most common complications (0.5% for both).

After adjusting for patient demographics, perioperative factors, and additional anesthetics used during the oral surgery procedure, multiple logistic regression analysis revealed subjects administered diazepam to have a 50% increased risk of adverse complications (Adjusted Odds Ratio [AOR] 1.50; 95% CI 1.05-2.16, P= 0.027).  Additionally, subjects were more likely to experience a complication if they had an increased ASA physical status, as well as an increased preoperative anxiety score (AOR 1.76; 95% CI 1.21-2.56, P= 0.003, and AOR 1.40; 95% CI 1.18-1.67, P< 0.01, respectively).

In conclusion, this study highlights the increased risk of perioperative anesthesia complications for patients given intravenous diazepam during third-molar procedures.  Additionally, this study further confirms the increased anesthetic risk when treating patients with an elevated ASA status or preoperative anxiety.  Future studies should continue to monitor the anesthetic regimens of at risk populations during oral surgery procedures to ensure the highest standard of safety within the specialty.

References

1. Perrott DH, Yuen JP, Andresen RV, et al: Office-based ambulatory anesthesia: Outcomes of clinical practice of oral and

maxillofacial surgeons. J Oral Maxillofac Surg 61:983, 2003

2. Aun C, Flynn PJ, Richards J, Major E: A comparison of midazolam and diazepam for intravenous sedation in dentistry. Anaesthesia 39:589-93, 1984