By Pooja Gangwani, D.D.S., M.P.H., Associate Professor and
Program Director of Oral and Maxillofacial Surgery, The Maurice H. Kornberg
School of Dentistry, Temple University
The use of recreational
cannabis in the United States has continued to increase since its legalization
by many states. One of the many areas of health care affected by this changing
landscape is the field of outpatient anesthesia. The potential for drug
interactions between cannabis and anesthetic medications is a significant
concern. The delivery of office-based ambulatory anesthesia care is a vital
component of the everyday practice of oral and maxillofacial surgeons (OMSs).
This article seeks to
examine considerations regarding the use of cannabis in the context of
outpatient anesthesia, exploring challenges and existing evidence on how
marijuana use can impact sedation and general anesthesia.
The principal psychoactive
constituent of marijuana is tetrahydrocannabinol (THC). Studies have documented
a dose-dependent increase in heart rate (HR) and systolic blood pressure (SBP)
in new cannabis users, which occurs immediately after smoking. Recreational and
medical cannabis use have been linked to severe cardiovascular disorders such
as sudden onset atrial fibrillation, malignant arrhythmias, coronary vasospasm,
myocardial infarction, sudden death, cerebral hypoperfusion and ischemic
stroke. Respiratory effects of cannabis consumption are also significant and
can lead to perioperative respiratory complications. Increased bronchial tone
and risk of hyperreactivity is seen in chronic users.
Documented
gastrointestinal side effects, such as recurrent nausea, vomiting and abdominal
discomfort, in chronic cannabis users are of great concern when performing
open-airway sedation procedures. Individual variability in the usage of cannabis
and tolerance makes sedation challenging, especially in determining appropriate
dosages and predicting its desired effects.
Several perioperative
recommendations regarding anesthesia in cannabis users are published. These
recommendations are based on pharmacologic and physiologic effects of cannabis and
THC and anecdotal evidence. The data on anesthetic requirements and changes in
vital signs under sedation and general anesthesia is sparse.
There are only two
retrospective studies in the OMS literature on this topic. In one retrospective
study, 189 patients (57 cannabis users, 132 non-users) were included. The study
concluded that cannabis users required more midazolam, fentanyl, propofol and
ketamine versus non-cannabis users during outpatient OMS procedures. In another
retrospective study, 53 patients (27 in THC+ group and 26 in THC- group) were
included. When comparing the two groups, the THC+ group required, on average,
higher doses of fentanyl and propofol during IV sedation. However, after
adjusting the effect of age, gender and weight, THC had no significant effect
on midazolam, fentanyl, propofol and ketamine requirements. Given the
retrospective nature of the above-mentioned studies, they have many
limitations.
Future studies could use a
prospective design to eliminate the variability and obtain more accurate data
with an improved sample size. More data will provide clarity and allow surgeons
to deliver optimal surgical care under anesthesia. A prospective clinical study
will be conducted at Temple University to provide more data and increase
understanding on this important issue.
References:
1. Echeverria-Villalobos M,
Todeschini AB, Stoicea N, Fiorda-Diaz J, Weaver T, Bergese SD. Perioperative
care of cannabis users: A comprehensive review of pharmacological and
anesthetic considerations. J Clin Anesth. 2019;57:41-49. doi:10.1016/j.jclinane.2019.03.011
2. Richards JR. Cannabinoid Hyperemesis
Syndrome: Pathophysiology and Treatment in the Emergency Department. J Emerg
Med. 2018;54(3):354-363. doi:10.1016/j.jemermed.2017.12.010
3. Ripperger D, Atte A, Ritto F. Cannabis Users
Require More Anesthetic Agents for General Anesthesia in Ambulatory Oral and
Maxillofacial Surgery Procedures. J Oral Maxillofac Surg.
2023;81(12):1460-1465. doi:10.1016/j.joms.2023.09.008
4. Gangwani
P, Lillian D, Dobbins J, Feng C, Vorrasi J, Kolokythas A. Is Recreational
Marijuana Use Associated With Changes in the Vital Signs or Anesthetic
Requirements During Intravenous Sedation?. J Oral Maxillofac Surg.
2023;81(5):527-535. doi:10.1016/j.joms.2023.01.007
Courtesy of
The Maurice H. Kornberg School of Dentistry, Temple University
Published on July 10, 2024