Page 26 - CASA Bulletin of Anesthesiology 2022; 9(5)

CASA Bulletin of Anesthesiology

Into the Weeds: Introduction to the Anesthetic Management for Patients
with Chronic Cannabis Use

2
2
1
Brittnee Haynes , Sandra Orfgen MD, Andrew Mannes MD
1 Medical student
2 Anesthesiologist, Department of Perioperative Medicine, Clinical Center, National Institutes of
Health, Bethesda, Bethesda, MD

Key words:
Anesthesia, anesthetic management, cannabis, marijuana

Introduction

Cannabis is a plant product that has been used for
therapeutic purposes by ancient civilizations, such as China,
Egypt, and India . The continued global spread of medicinal
1, 2
cannabis eventually resulted in cannabis being described in the
United States Pharmacopoeia in 1850 . Throughout the 1900s,
2, 3
the institution of multiple federal restrictions against cannabis in
the United States culminated in the classification of cannabis as
a Schedule I drug by the Controlled Substances Act of 1970 .
4, 5
Since the 1996 passage of legislation in California permitting
the use of medical cannabis, most state governments have
legalized the use of cannabis, whether for recreational use,
medicinal use, or both.

With the continued rise of both recreational and medicinal cannabis use, perioperative
clinicians are increasingly likely to encounter patients using cannabis. Accordingly, it is
important for perioperative providers to have a well-rounded understanding of the additional
anesthetic considerations for patients using cannabis, regardless of the legalization status of the
drug. Further, the anesthetic management for patients using cannabis is a challenge due to
several factors, including multi-system effects of cannabis, variable and unknown compositions
of biologically active compounds of cannabis, and conflicting research findings with a lack of
high-quality studies due to federal limitations and criminalization of cannabis.

Basics of the Endocannabinoid System

The endocannabinoid system (ECS) is a diffuse neuromodulatory system that plays a major
role in homeostasis, such as in cardiovascular, endocrine, pain, neurologic, cognitive, and
immune functions . The main endogenous ligands of the ECS are anandamide (AEA) and 2-
6, 7
arachidonoylglycerol (2-AG), which are cannabinoids synthesized from arachidonic acid, a fatty
acid found in the cell membrane . AEA and 2-AG are released in response to overstimulation
6, 7
of post-synaptic neurons, and then bind to cannabinoid receptors to downregulate pre-synaptic
excitatory signaling .
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