The Impact of Marijuana on Anesthesia: What You Need to Know

Marijuana and Anesthesia

Marijuana use has become increasingly prevalent in society, raising important considerations for anesthesia providers. Understanding the impact of marijuana on anesthesia is crucial to ensure safe and effective perioperative care. This section provides an overview of marijuana use and the legal status and regulation surrounding its use.

Overview of Marijuana Use

Marijuana, also known as cannabis, is the most commonly used illicit drug in the United States. It is derived from the Cannabis sativa plant and contains various compounds known as cannabinoids, including tetrahydrocannabinol (THC) and cannabidiol (CBD) [1]. Historically, cannabis products had different degrees of legality in the United States. However, the Controlled Substance Act of 1970 classified all cannabis products as Schedule I substances, with high abuse potential and no accepted medical use.

In recent years, there has been a shift in the legal status and regulation of marijuana. While it remains classified as a Schedule I substance at the federal level, many states have passed less stringent legislation related to its use. This has led to variations in the legal status and availability of marijuana products across different regions. With the widespread availability of cannabis products, it is expected that an increasing number of patients with a history of chronic marijuana use will present for anesthesia [1].

Legal Status and Regulation

The legal status of marijuana varies depending on the jurisdiction. In some states, both medical and recreational use of marijuana is legal, while in others, it may be legal only for medical purposes or completely illegal. It is important for anesthesia providers to be aware of the legal status and regulations in their specific region to ensure compliance and provide appropriate care.

Legalization and regulation of marijuana involve considerations such as age restrictions, possession limits, cultivation, distribution, and taxation. These regulations aim to balance public health and safety concerns while addressing the potential medical benefits of marijuana. It is essential for healthcare professionals to stay informed about the evolving legal landscape regarding marijuana use to provide optimal care and guidance to patients.

Understanding the overview of marijuana use and the legal status and regulation surrounding it lays the foundation for exploring the pharmacological aspects, anesthesia considerations, effects on health, and patient implications related to marijuana use in the context of anesthesia. By staying informed and up-to-date on this topic, anesthesia providers can effectively navigate the challenges and deliver safe care to patients who have used marijuana.

Pharmacological Aspects

To understand the impact of marijuana on anesthesia, it is important to examine the pharmacological aspects of marijuana use, including its key compounds and effects on anesthesia.

Key Compounds in Marijuana

Marijuana contains various chemical compounds known as cannabinoids, which are responsible for its psychoactive and medicinal effects. The two primary cannabinoids found in marijuana are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is primarily responsible for the psychoactive effects, while CBD has more therapeutic properties.

These cannabinoids interact with the body's endocannabinoid system, which plays a role in regulating various physiological processes such as pain, mood, and appetite. The concentration of THC and CBD can vary significantly between different strains and types of marijuana products.

Effects on Anesthesia

The effects of marijuana on anesthesia can vary depending on several factors, including the dose, frequency of use, and individual patient characteristics. Research suggests that chronic marijuana smokers may have a higher risk of developing atheromatous disease due to the relatively high amount of carbon monoxide in marijuana cigarettes compared to tobacco cigarettes. Carbon monoxide can impair oxygen delivery to tissues and potentially impact anesthesia management.

When it comes to anesthesia administration, cannabis users may require higher induction doses of propofol, a commonly used anesthetic agent. Additionally, they may experience worse postoperative pain, necessitating higher doses of rescue analgesics in the postoperative period.

It is worth noting that cannabis users may also require higher doses of sedation for certain procedures, such as upper endoscopic procedures, compared to non-users. However, further research is needed to fully understand the implications of marijuana use on different anesthesia techniques and procedures.

It is important for healthcare providers to be aware of a patient's marijuana use prior to anesthesia administration. This information can help determine appropriate anesthetic requirements and postoperative pain management strategies. Open communication between patients and healthcare professionals is crucial in order to provide safe and effective anesthesia care.

By understanding the pharmacological aspects of marijuana, including its key compounds and effects on anesthesia, healthcare providers can make informed decisions regarding anesthesia management for individuals who use marijuana. However, further research is needed to explore the specific interactions between marijuana and anesthesia in different patient populations and surgical procedures.

Anesthesia Considerations

When it comes to the impact of marijuana on anesthesia, there are important considerations to keep in mind. These considerations primarily revolve around anesthetic requirements and postoperative pain management.

Anesthetic Requirements

Research suggests that individuals who are chronic marijuana smokers may require higher induction doses of propofol, an intravenous anesthetic, compared to non-users. This means that higher doses of propofol may be needed to achieve the desired level of anesthesia in individuals who regularly use marijuana. Additionally, cannabis users may require higher doses of sedation for certain procedures, such as upper endoscopic procedures, compared to non-users. It is important for anesthesia providers to be aware of these potential differences in drug requirements and adjust their dosing accordingly to ensure safe and effective anesthesia.

Postoperative Pain Management

After surgery, effective pain management is crucial for a patient's comfort and recovery. It has been observed that cannabis users may experience worse postoperative pain, which could require higher doses of rescue analgesics in the postoperative period compared to non-users. This suggests that cannabis users may have a higher pain threshold or altered pain sensitivity that needs to be taken into consideration when planning postoperative pain management strategies. Anesthesia providers should carefully assess and monitor pain levels in cannabis users and adjust pain medications accordingly to provide adequate relief.

It's important for patients who use marijuana to disclose their usage to their anesthesia provider during the preoperative evaluation. This information allows the anesthesia provider to make informed decisions regarding anesthetic dosing and pain management strategies. Open communication between the patient and the anesthesia team is essential to ensure the best possible anesthesia experience and postoperative outcomes.

As with any medical procedure, individual responses and needs may vary. Anesthesia providers will consider the specific circumstances of each patient and adjust their approach accordingly. By understanding the potential impact of marijuana on anesthetic requirements and postoperative pain management, anesthesia providers can optimize the care provided to individuals who use marijuana.

Effects on Health

When considering the impact of marijuana on anesthesia, it is important to understand the potential effects on health, particularly in relation to respiratory health and cardiovascular risks.

Respiratory Effects

Smoking marijuana can have adverse effects on respiratory health. It increases the risk of breathing problems, such as wheezing, coughing, chronic bronchitis, and thermal injury to the throat and airway. In fact, symptoms may occur 10 years earlier in marijuana smokers compared to tobacco smokers.

A study estimated that smoking 3-4 cannabis cigarettes daily has an equivalent effect of about 20 tobacco cigarettes in terms of bronchial tissue damage. Additionally, smoking marijuana can cause the swelling of the uvula, which may persist for 12-24 hours after use.

It is important to note that vaping marijuana is not significantly safer than smoking it. Chronic marijuana vaping can lead to lung cell damage, inflammation, an increased risk of respiratory infections, substance use disorder, addiction, and other health issues.

Cardiovascular Risks

Marijuana use can have an impact on cardiovascular health. It has the potential to raise heart rate and lower blood pressure. This combination can cause a severe lack of blood supply to the heart muscle (ischemia), potentially leading to a heart attack, especially in patients with pre-existing heart disease.

Regular cannabis users may also be at a higher risk of adverse cardiovascular events, such as tachycardia and increased myocardial oxygen demand. These events can have serious implications for individuals undergoing anesthesia and surgery.

To mitigate these risks, it is generally recommended that individuals stop using cannabis products within 72 hours before general anesthesia for surgery. It is crucial for patients to inform their anesthesiologist about their marijuana use, as this information is essential for making appropriate care plans and being prepared for any potential complications that may arise during the perioperative period.

The effects of marijuana on respiratory and cardiovascular health highlight the importance of open communication between patients and healthcare professionals. By providing accurate and detailed information about marijuana use, patients can ensure that their anesthesiologist is well-informed and can make informed decisions to optimize their perioperative care.

Patient Implications

When it comes to the impact of marijuana on anesthesia, there are important considerations for patients both before and after surgery. Understanding these implications is crucial to ensure a safe and successful surgical experience.

Preoperative Preparation

Patients who use cannabis prior to surgery may face increased risks during and after the surgical procedure. It is essential to inform the anesthesiologist about cannabis use to ensure appropriate care plans are made and to be prepared for any potential complications that may arise. By providing this information, the anesthesiologist can make informed decisions and adjustments to the anesthesia plan to mitigate risks [5].

Additionally, regular cannabis users may experience more pain and nausea after surgery compared to non-users. This may necessitate higher doses of pain medication, potentially including opioids. However, it is important to consider other medications before resorting to opioids. Collaborating with the anesthesia team can help develop an appropriate pain management plan for patients who use cannabis regularly.

Furthermore, patients should be aware that smoking marijuana shortly before surgery could increase the risk of a heart attack during or after the procedure. It is advisable to refrain from smoking marijuana on the day of surgery, and guidelines recommend waiting at least two hours after the patient's last use before undergoing surgery.

Postoperative Care Recommendations

After surgery, patients who are regular cannabis users may experience withdrawal symptoms, particularly if they use cannabis regularly. It is important to inform the anesthesiologist about cannabis use to allow for consideration and planning in managing potential withdrawal symptoms post-surgery. For those using products containing only CBD, the risk of withdrawal symptoms is minimal.

In terms of resuming marijuana use after surgery, there is no definitive research on when it is safe to do so. The decision should be made in consultation with the anesthesiologist, surgeon, or care team, taking into account the type of surgery performed and the patient's medical history. It is recommended to seek guidance from the healthcare professionals involved before resuming cannabis use post-surgery.

By being aware of these patient implications and actively communicating with the healthcare team, patients can play an active role in ensuring their safety and optimizing their surgical outcomes when using marijuana in the context of anesthesia.

Research Gaps and Recommendations

As the use of marijuana becomes more prevalent, there is a need for further research to better understand its impact on perioperative care and anesthesia. Currently, there are knowledge gaps in this area, and more studies are required to address the following areas:

Knowledge Gaps in Perioperative Care

The perioperative uses of cannabis and the management of cannabis users present significant knowledge gaps in the field of anesthesia. According to a study published in PubMed Central, existing research is limited, with small sample sizes and heterogeneity in study designs, making it challenging to draw definitive conclusions. Therefore, further investigations are needed to explore the effects of cannabis on anesthesia and perioperative outcomes.

Some specific areas that require attention include:

• The optimal anesthetic requirements for cannabis users: Determining the appropriate doses of intravenous and volatile anesthetic agents for individuals who use cannabis is crucial. Research suggests that cannabis users may require higher doses of anesthesia to achieve the same depth of anesthesia as non-users. Further studies can help establish clear guidelines for anesthetic management in this population.
• Understanding the impact of cannabis on postoperative pain management: Studies have indicated that cannabis users may experience higher pain scores and poorer sleep quality in the post-operative period [6]. Exploring the relationship between cannabis use and pain management can guide healthcare providers in developing appropriate strategies for pain control in patients who use cannabis.
• Evaluating the effectiveness of cannabis for post-operative nausea and vomiting (PONV): Although cannabis is sometimes used for the prevention or treatment of PONV, research has not proven its efficacy in this regard. Further investigation is needed to determine whether cannabis can be a viable option for managing PONV.

Future Research Directions

To address the knowledge gaps in perioperative care related to cannabis use, future research should focus on the following areas:

• Conducting large-scale studies: Increasing the sample size and using standardized study designs can provide more robust evidence regarding the effects of cannabis on anesthesia and perioperative outcomes. Large-scale studies can help establish clear correlations and draw meaningful conclusions.
• Longitudinal studies: Long-term studies that follow patients who use cannabis from preoperative to postoperative stages can provide valuable insights into the impact of cannabis on various aspects of perioperative care. This can include examining the long-term effects on pain management, postoperative recovery, and complications.
• Standardized protocols and guidelines: Developing standardized protocols and guidelines for the perioperative care of cannabis users can assist healthcare providers in optimizing anesthesia management and postoperative care. These guidelines should consider factors such as dosing, drug interactions, and potential complications associated with cannabis use.
• Collaborative research efforts: Collaboration between researchers, anesthesiologists, surgeons, and other healthcare professionals is essential to ensure comprehensive and multidisciplinary research in this field. By combining expertise and resources, research efforts can be more impactful and provide a better understanding of the implications of cannabis use in the perioperative setting.

By addressing these research gaps and pursuing future research directions, we can enhance our understanding of the impact of marijuana on anesthesia and perioperative care. This knowledge will enable healthcare providers to deliver safe and effective care to patients who use cannabis during the perioperative period.

References

• ‍https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6650211/
• ‍https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8764743/
• ‍https://www.facs.org/for-patients/preparing-for-surgery/marijuana-and-surgery
• ‍https://www.health.harvard.edu/blog/coming-clean-your-anesthesiologist-needs-to-know-about-marijuana-use-before-surgery-2020011518642
• https://www.asahq.org/madeforthismoment/preparing-for-surgery/risks/cannabis-surgery-made-moment
• ‍https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6922064/