ArticlePDF AvailableLiterature Review

Surgical considerations of marijuana use in elective procedures



Background Marijuana consumption is estimated as upwards of 9.5% of the U.S. adult population. Nevertheless, few trials exist on potential implications for surgical outcomes amongst users. Methods A current literature review explored marijuana's effects to answer: (I) How is marijuana use screened for in clinical and pre-operative settings? (II) What are potential surgical complications of marijuana use? (III) How should surgeons handle patient marijuana use regarding elective surgery? (IV) Are marijuana's effects the same or different from those of tobacco? Results In acute settings, marijuana's effects peaked at approximately 1 hour post initiation, lasting 2–4 hours. Marijuana increased cardiac workload, myocardial infarctions and strokes in young, chronic users. Cannabis caused similar pulmonary complications to those of a tobacco smoker. Marijuana caused airway obstruction and increased anesthetic dosages needed to place laryngeal airways. Use within 72 hours of general anesthesia was advised against. In vitro and in vivo studies were contradictory regarding prothrombic or antithrombotic effects. Conclusions Marijuana use is problematic to surgeons, left without evidence-based approaches. In emergency settings, marijuana use may be unavoidable. However, further research would provide much needed information to guide elective procedures.
Review Article
Surgical considerations of
marijuana use in elective
Henry B. Huson
, Tamara Marryshow Granados
, Yvonne Rasko
Department of Surgery, Louisiana State University Health Sciences Center, New Orleans, LA, USA
Department of Family Medicine, Brown University, Pawtucket, RI, USA
Division of Plastic Surgery, University of Maryland Medical Center, Baltimore, MD, USA
Corresponding author.
E-mail address: (H.B. Huson).
Background: Marijuana consumption is estimated as upwards of 9.5% of the U.S.
adult population. Nevertheless, few trials exist on potential implications for surgical
outcomes amongst users.
Methods: A current literature review explored marijuanaseects to answer: (I)
How is marijuana use screened for in clinical and pre-operative settings? (II)
What are potential surgical complications of marijuana use? (III) How should
surgeons handle patient marijuana use regarding elective surgery? (IV) Are
marijuanaseects the same or dierent from those of tobacco?
Results: In acute settings, marijuanaseects peaked at approximately 1 hour post
initiation, lasting 2e4 hours. Marijuana increased cardiac workload, myocardial
infarctions and strokes in young, chronic users. Cannabis caused similar
pulmonary complications to those of a tobacco smoker. Marijuana caused airway
obstruction and increased anesthetic dosages needed to place laryngeal airways.
Use within 72 hours of general anesthesia was advised against. In vitro and
in vivo studies were contradictory regarding prothrombic or antithrombotic eects.
Conclusions: Marijuana use is problematic to surgeons, left without evidence-
based approaches. In emergency settings, marijuana use may be unavoidable.
26 June 2018
5 September 2018
5 September 2018
Cite as: Henry B. Huson,
Tamara Marryshow Granados,
Yvonne Rasko.Surgical
considerations of marijuana
use in elective procedures.
Heliyon 4 (2018) e00779.
doi: 10.1016/j.heliyon.2018.
2405-8440/Ó2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
However, further research would provide much needed information to guide
elective procedures.
Keywords: Evidence-based medicine, Surgery, Health profession
1. Introduction
Marijuana use dates back to 2727 BC to Chinese Emperor Shen Nung. After
spreading through the Greek and Roman empires and into the Islamic empire of
North Africa and the Middle East, it was brought to the Western hemisphere by
the Spanish [1]. Originally lauded for its utility as ber, it was not until its migration
into North America that it began to be used in a similar fashion as it is today. Used in
the form of hemp, it was seen throughout society as rope, clothing and even paper.
While marijuana has been used by Americans recreationally for years, it is a subject
that is becoming more commonplace in our modern society. According to the Na-
tional Institutes of Health, marijuana use in 2015e2016 rose from 4.1% to 9.5%
of the U.S. adult population [2]. With more states eliminating the legal ramications
of its use and a growing debate about its federal legality, this is a subject that
routinely makes local and national headlines. With a diverse array of commercial
products becoming available from chocolate squares to oral sprays, marijuana is
also no longer restricted to a rolled cigarette.
The medical community has also joined the debate. The most obvious correlation
between medicine and marijuana is medicinal marijuana. Marijuanaseects have
been well documented, allowing the push for its use as medicine within multiple spe-
cialities. Proponents of its use point to its eects on the endocannabinoid system.
Studies show that through its impact on dierent pathways it may be used as an anal-
gesic, immunosuppressant, muscle relaxant, anti-inammatory agent, appetite
modulator, antidepressant, antiemetic, bronchodilator, neuroleptic, antineoplastic
and antiallergen [3]. Medical marijuana also diers in chemical composition, con-
taining a higher tetrahydrocannabinol (THC) concentration and less cannabinol
than the recreational version. This is even before taking into consideration the
various extraneous agents that may be found within the available recreational
drug [4].
There is however, very little, if any research evaluating marijuanas use in surgery.
This paucity of literature presents a problem. While many surgeons may ask about
recreation drug use including marijuana, many other drugs have established evi-
dence based outcomes that allow variation in surgical planning as needed. However,
when it comes to marijuana, surgeons are left to determine what to do with this in-
formation on their own.
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Despite the multiple studies on the physiologic eects of marijuana use, clinical
studies, if any, are not cited in the medical literature. This study reviews the literature
available on marijuanaseects and discusses potential complications that may
result within the surgical setting. With a reported estimation of 10%e20% of patients
between the ages of 18 and 25 years regularly using marijuana [4], this review seeks
to become an initial step for further exploration of the subject and to reveal why there
is a need for more in-depth research.
2. Main text
2.1. Methods
2.1.1. Study collection
A search on the eects of marijuana, marijuana and elective surgery, and marijuanas
eects on surgery was undertaken in PubMed, Medline, EMBASE, and Articles were reviewed using the keywords "marijuana,"
"elective surgery," "surgery," anesthesia,”“complication,”“THC,”“tobaccoand
"cannabis." After removing duplicates, 263 studies resulted. After articles were
identied, attention was paid to study design, type, outcomes and publication. The
authors independently reviewed titles and abstracts to ascertain relevance to the
topic at hand. Authors also searched reference lists of included studies as well as
other narrative reviews.
2.1.2. Data consideration
Due to limited research and reviews on this subject, information was utilized from
articles on surgery in various elds, such as orthopedic, dental and bariatric with
anesthesia considerations and general topics related to marijuana also examined.
The following information was gathered: marijuanas prevalence in the United
States, marijuanaseects on the cardiovascular system and pulmonary system, po-
tential coagulopathies, marijuanaseects in relation to anesthesiology, evidence
based screening methods for recreational drug use, potential surgical complications
that may result from marijuana use, and recommendations on marijuana use and
2.1.3. Analysis
Information pulled from the literature was used to answer the following key ques-
tions: (I) How is marijuana use screened for in clinical and pre-operative settings?
(II) What are potential complications in the surgical setting of marijuana use? (III)
How should surgeons handle patient marijuana use regarding elective surgery?
(IV) Are marijuanaseects the same or dierent from those of tobacco?
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2.2. Results
2.2.1. Pharmocological eects
When marijuana is smoked, THC and other cannabinoids are absorbed rapidly
through the lungs with eects peaking in 15 minutes. These eects can persist for
up to a dose-dependent 4 hours in the acute setting. When ingested orally however,
onset of eects is slower (15 minutes versus 90 minutes) but has a longer duration of
action (4 hours versus 5e6 hours), due to continued absorption in the gut. This is
despite a lower bioavailability due to rst-pass metabolism by the liver which results
in a blood concentration 25% of what is obtained if smoked. The cognitive/psycho-
motor eects can be present for up to 24 hours regardless of administration route [4].
Cannabinoids are highly lipid soluble. This leads to a slow release into the blood-
stream with a single dose not fully eliminated for up to 30 days [5].
The cardiovascular eects of marijuana use range from benign to worrisome based
on the timeline of use and dosage. In a series single blind study comparing the eects
of high and low doses of THC in healthy young men, tachycardia was induced
beginning within the time of inhalation, and persisting at least 90 minutes, with
the maximum heart rate reached at an average of 30 minutes. The study also found
a signicant elevation in systolic and diastolic blood pressures as well as the pres-
ence of premature ventricular contractions (PVCs) in subjects who received the
higher doses. These experiments showed a correlation between the dose and the ta-
chycardic and cardiovascular changes [6]. In addition, Malit et al.sstudy on the ef-
fects of intravenous THC found the majority of patients to exceed the 100 beats per
minute mark but also experience intermittent spikes in heart rate with a possible eti-
ology of psychological distress [7]. Beaconseld et al. postulated a mechanism of
beta adrenergic stimulation for the tachycardia as he was able to block the tachy-
cardia with the use of propranolol [8].
Pharmacology lays credence to this. At lower or moderate doses, marijuana increases
sympathetic activity reducing parasympathetics and producing an elevation in heart
rate, cardiac output and blood pressure. However, the opposite is true as the dosage in-
creases. At high doses, the parasympathetic system takes over, leading to bradycardia
and hypotension with animal studies postulating that the sympathetic inhibition occurs
due to the bioactive constituent of cannabisseects on the CB1 receptors [9].
In addition to sinus tachycardia, marijuana use has been linked to multiple electro-
cardiogram (ECG) changes in various case reports. Daccarrett et al. found Brugada-
like changes in a 19 year old male with a known history of cannabis use and no
anatomical/functional abnormalities [10]. A case was also reported in which
cannabis use was linked to the development of atrial utter and atrial brillation
[11], while other studies have reported the presence of sinus bradycardia and AV
block [12,13].
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Marijuana use also has a role as a risk factor for myocardial infarction. Aronow et al.,
found that while comparing marijuana to placebo, cannabis causes an increase in car-
boxyhemoglobin, a resultant increase in myocardial oxygen demand, decrease in ox-
ygen supply as well as an induction of platelet aggregation [14]. One case report
showed a 21 year old male who presented with a ST elevation myocardial infarction
due to plaque rupture as a complication of marijuana use [15]. In Mittleman et al.s
analysis of over 3,800 cases of myocardial infarction, 124 patients reported use
within the last year of which 37 reported use within 24 hours, with 9 reporting
use within an hour of the event. The study found a statistically signicant 4.8
fold increase in myocardial infarction within the rst hour of marijuana use
(P <.001). In fact, as THC content of marijuana increases, there are a growing num-
ber of clinical studies demonstrating the association between cannabis use and
adverse cardiovascular events. One such study followed 1913 adults prospectively
and demonstrated that in patients with prior myocardial infarction, marijuana use
up to once per week increased risk of death 2.5 fold while more frequent use yielded
a fourfold risk of dying [16].
Marijuana has also been reported as a risk factor for stroke. Over 80 cases have been
reported in which patients had strokes, with a higher prevalence of ischemic strokes,
that were associated with either a recent increase, in the days leading up to the event,
or chronic history of heavy marijuana use. They believed that the marked swings in
blood pressure or the reversible cerebral vasoconstriction that resulted from mari-
juana use were likely mechanisms of stroke but admitted that no rm conclusions
could be drawn without further studies [17]. In addition, Lawson reported a similar
belief that drug induced vasospasm was a plausible explanation for TIAs, but also
with the caveat that due to the confounding medications/illicit substances being
used in his patient, no direct association could be determined [18].
Also of interest is marijuana useseect on other cardiovascular vessels. When
cohort studies were performed comparing marijuana users with resultant limb arter-
itis to patients suering from thromboangiitis obliterans, marijuana associated arter-
itis occurred in younger, usually male patients with a unilateral, lower limb as the
common presentation [19].
The most common route of marijuana administration is inhalation via smoking. Due
to the unltered nature of the marijuana cigarette compared to commercially avail-
able tobacco cigarettes, the amount of carcinogens and irritants, like tar, that enter
the upper airway is increased [20] with approximately a three-fold increase in tar
inhalation and one third more tar deposition in the respiratory tract [21]. More spe-
cically, the tar produced from cannabis smoke contains greater concentration of
benzanthracenes and benzopyrenes (each a carcinogen) than tobacco smoke [22].
In addition, as compared to smoking tobacco, there is a two-thirds greater puvol-
ume, one-third greater depth of inhalation and a four-fold longer breath-holding
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time, all of which are common practices to try to maximize THC absorption, which
is around 50% of cigarette content [21]. These practices result in ve times the
amount of carboxyhemoglobin levels as compared to the typical tobacco smoker
[23] despite the presence of similar quantities of carbon monoxide from the incom-
plete combustion of the organic compounds found within each product [24]. In re-
porting his case, Schwartz theorized that high temperatures in which marijuana burns
compared to tobacco may increase the irritancy of marijuana to the mucous mem-
branes [25]. While the higher temperature is a possibility, the evidence of mari-
juanas irritancy is well documented. In a cohort study comprised of 40 healthy
patients, Roth et al. showed that cannabis smokers had signicantly increased visual
bronchitis index scores resulting from large airway epithelial damage, edema, and
erythema. On mucosal biopsy, goblet cell hyperplasia with subsequent increase in
secretions, loss of ciliated epithelium and squamous metaplasia were also present
in 97% of smokers. They concluded that marijuana use is associated with airway
inammation that is similar to that of a tobacco smoker [26]. A cross-sectional study
on over 6000 patients, from 1988 to 1994, found an increased incidence of chronic
bronchitis symptoms such as wheezing and productive cough occurring in patients
10 years younger, on average, than tobacco smokers [27]. Case-control trials per-
formed found similar ndings with regards to increases in wheezing, shortness of
breath, cough and phlegm as well as the similarities with tobacco use [20].
Bryson also concluded based on his review of the literature, that the pulmonary com-
plications in the chronic marijuana smoker are equivalent to those seen in the chronic
tobacco smoker [28], while Wu et al. estimated that 3e4 cannabis cigarettes daily
equates to about 20 tobacco cigarettes in terms of bronchial tissue damage [21].
Cannabis use has also been linked to a higher risk in cancers, possibly due to the
increased carcinogens entering the airway. Similar to tobacco use, marijuana use
plays a signicant role in the development of lung cancer. In a case control study
performed in New Zealand, young adults (under the age of 55) had an 8% increase
in lung cancer risk for each joint year of cannabis smoking after adjusting for the
cofounders, such as age, sex, ethnicity and family history [29]. Berthiller et al.
pooled data from a multitude of institutions across multiple countries, comprising
of over 1200 patients, and reported an increased risk of lung cancer for every mari-
juana use [30]. In addition, a 40 year cohort study (1969e2009) with about 48,000
patients reported an increased risk of lung cancer in young men (aged 18e20 years
old) who had smoked marijuana more than 50 times. This study was limited however
by the nature of patient self-reporting [31]. Head and neck cancers have also been
theorized to be at a higher risk similar to that of tobacco smoking. However, a pooled
analysis performed by Berthiller et al. found that infrequent marijuana smoking did
not confer a greater risk after adjusting for cofounders. The authors did note that due
to the low prevalence of frequent smoking within the study population, that a moder-
ately increased risk could not be ruled out [32]. In another population based case
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control study, there was an increased incidence of head and neck cancers in patients
with a 30 joint-year history, yet the association did not exist when accounting for
tobacco smoking [33] suggesting the risk is greater with tobacco than marijuana.
2.2.2. Impact on anesthesia
Marijuanas prevalence is evident amongst all patient populations. In a cross-
sectional study conducted by Mills et al., the rate of marijuana use via patient
self-reporting was found to be 14% amongst surgical patients in 2003. This led
the authors to conclude that questions about illicit drug use should be a routine
part of the preanesthetic assessment, especially in patients that the anesthesiologist
nds hard to settle, due to anxiety or other psychologic manifestations, because of
the potential anesthetic complications that may occur [34].
In a series of case reports, Guarisco presented three patients who suered from sig-
nicant respiratory distress due to isolated uvulitis, a disease of low incidence typi-
cally associated with infection or traumatic irritation from instruments used in the
airway. Investigating further, all three patients were found to have inhaled large
quantities of cannabis within six to twelve hours of the onset of symptoms leading
to the conclusion of a possible correlation with inhaled irritants such as cannabis.
Due to known cases of isolated uvulitis [35,36] and the possible link with marijuana,
the authors suggest that toxicology urine and blood studies for THC should be per-
formed in cases where marijuana use is suspected but not conrmed by history tak-
ing [37]. Multiple other cases have also been reported with similar ndings. In a case
series by Sloan, three adolescents suered acute uvular inammation post the heavy
use of marijuana, having smoking at least three marijuana cigarettes, despite nega-
tive throat cultures [38]. In 1971, a cohort study was performed in which a large
quantity of marijuana, over 100 grams, was smoked over several months. Of the
31 subjects, almost half suered from recurrent rhinopharyngitis as well as devel-
oped acute uvular edema after the heavy marijuana inhalation which lasted approx-
imately 12e24 hours [39]. These ndings stress the importance in the maintenance
of the airway during anesthesia following acute marijuana use due to the potential
airway obstruction that may occur.
In fact, in presenting a case of uvular edema and airway obstruction with cannabis
inhalation 4 hours prior to surgery, Pertwee recommended that elective operations
should be avoided altogether if a patient was recently exposed to cannabis smoke
[40]. This recommendation seems reasonable when taking into consideration the
life-threatening bronchospasm leading to asphyxia, brain damage or death resulting
from tracheal intubation in patients with obstructive airways [41]. One proposed
course of action has been the therapeutic use of steroids. In Guariscos study, he
theorized that steroids should help inhaled irritant uvulitis [37]. As steroids increase
endotracheal permeability, decrease mucosal edema and stabilize lysosomal
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membranes, thus decreasing the inammatory response, the theory has scientic ba-
sis. In a prospective, randomized, double-blind study, Silvanus et al. found that the
addition of methylprednisolone to salbutamol in patients with a partially reversible
airway obstruction helped in the diminution of the reex bronchoconstriction that
can result from tracheal intubation [42]. This led to Hawkins et al.srecommenda-
tion that at the rst signs of airway obstruction, dexamethasone should be used as the
drug of choice, 1 mg/kg every 6e12 hours over the course of one to two days (Haw-
kins). This recommendation gained credence in the dramatic relief that dexametha-
sone provided in the post-traumatic cases [35,36]. However, Mallat et al. concluded
that although marijuana-induced uvular edema is a serious postoperative complica-
tion that has a potential for simple treatment, in the case of an elective surgical pro-
cedure with an acute history of cannabis exposure, surgery should be cancelled as
prophylactic treatment may not be ecient [43]. The complications of the airway
are not limited to intubation however. The inhalation of toxic chemicals as well as
smoke can cause laryngospasm by chemoreceptor stimulation. In addition, the inha-
lation of hot gasses can trigger laryngospasm via thermoreceptor stimulation, espe-
cially in the case of lowered sensory aerent neuron threshold potentials such as in
light anesthesia. In line with this, White presented a case in which a known cannabis
smoker suered severe laryngospasm following extubation [44].
As found within the reviews, multiple observations have been made showing cross-
tolerance between marijuana and barbiturates, opioids, prostaglandins, chlorproma-
zine and alcohol. In addition, animal studies have shown additive eects amongst
them all except for alcohol [45,46]. These drug interactions have led to further
exploration of its reactions to other medication groups. As a result of fat sequestra-
tion and subsequent slow elimination from the tissues, cannabinoids may be present
to interact with multiple anesthetic agents. In Symonss case report, the patient
required multiple boluses of propofol and two additional doses of midazolam to
achieve appropriate sedation [47]. In a prospective, randomized, single-blind study
of 60 patients, chronic marijuana users required signicantly increased doses of pro-
pofol to facilitate successful insertion of the laryngeal mask and thus suggesting that
the increased doses, in chronic marijuana users, may be a requirement for appro-
priate loss of consciousness as well as jaw relaxation and airway reex depression.
The authors theorized that the variations in the level of delta9-THC can explain var-
iations in propofol responses [48]. In a review written in the American Association
of Nurse Anesthetists Journal, Dickerson reported the synergistic eects of cannabis
to include: potentiation of nondepolarizing muscle relaxants, potentiation of norepi-
nephrine, the augmentation of any drug causing respiratory or cardiac depression, as
well as a more profound response to inhaled anesthetics sensitization of the myocar-
dium to catecholamines due to the increased level of epinephrine [49]. On the subject
of muscle relaxants, THC depletes acetylcholine stores and exerts an anticholinergic
eect and thus creates a potentiation of the nondepolarizing muscle relaxants [50].A
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review by Hall et al. explored THCs interaction with drugs aecting heart rate and
arterial pressure and found that due to cannabiss own cardiovascular eects (as dis-
cussed previously), it may interact with medications such as beta-blockers, anticho-
linergics and cholinesterase inhibitors [51]. Due to these potential autonomic
reactions, as well as theoretical psychiatric complications, such as withdrawal eects
and their interference with anesthetic induction or postoperative recovery, there has
been a stress made to inquiring about drug history [52,53] or avoiding elective op-
erations altogether [53]. Dickerson, in his review, recommended that, due to all po-
tential eects and interactions, not only should an extensive history of drug use be
elicited at the time of the preoperative assessment, including the frequency of use
and time of last use, but that anesthesia should be avoided in any patient with
cannabis use within the past 72 hours [49]. This gained further credibility in a ran-
domized, double-blind trial, in which an apparent drug interaction was observed in
the patient population who underwent general anesthesia within 72 hours of mari-
juana use leading to a sustained postoperative tachycardia, a nding potentially
due to an interaction between cannabinol metabolites and atropine administration
during anesthesia [54].
2.2.3. Peri-operative complications
One of the most researched and known risk factor for peri- or postoperative compli-
cations, increased hospitals costs and resource usage is smoking, specically to-
bacco smoke. In fact, the rates of perioperative respiratory events, such as re-
intubation, hypoventilation, hypoxemia, laryngospasm, bronchospasm, and aspira-
tion, have a total incidence of 5.5% in smokers compared to 3.1% in nonsmokers,
making these events 70% more prevalent with smoking [55]. In addition, in a ran-
domized controlled trial out of Denmark, orthopedic surgery patients who smoked
were compared to those who underwent cessation counseling and nicotine replace-
ment therapy. In the study, they found an overall complication rate of 18% compared
to the 52% found in the smoking group, including a cardiac event rate of 0%
compared to 10% [56]. A similarly designed study found a signicant relative risk
reduction of 49% for not only systemic complications but that of wounds as well
[57]. These call into question the role of marijuana on perioperative complications,
especially when taking into consideration that the pulmonary complications in the
chronic cannabis smoker are equivalents to that of a chronic tobacco smoker, prob-
ably due to the cannabis smoke products [28]. One such pulmonary complication is
airway obstruction, extensively linked to marijuana use [35,36,37], in which
Warner et al. found that untreated, such as a lack of smoking cessation in the case
of marijuana, leaves patients at a high risk for perioperative complications [58].
When it comes to the case of cardiovascular maintenance in the perioperative period,
marijuana presents complications. As mentioned previously, cannabis use can create
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a series of ECG changes that must be considered and monitored such as PVCs [6],
atrial brillation [11], AV block [12,13], or Brugada-like changes [10]. As a worst
case scenario, cannabis use has been linked to plaque rupture and resultant myocar-
dial infarction [15]. These are all causes for concern considering that Gregg et al.
reported, in conducting a series of 55 clinical trials in patients medicated with
THC, that peak heart rate increased by 24.1% in surgical patients compared to the
non-surgical. The authors concluded that THC may have a synergistic cardiovascu-
lar relationship with surgical stress [54]. This tachycardia gave credence to Brysons
recommendation that ketamine, pancuronium, atropine and epinephrine, all drugs
known to aect heart rate, should be avoided in patients with history of acute mari-
juana use [28], while the bradycardia and hypotension that results from high doses of
marijuana called into question the amount of atropine and vasopressors needed [9].
Despite the impetus behind these recommendations, 1 trial showed epinephrine to
have no synergistic eect with marijuana when it comes to cardiovascular eects
[54], showing more research is needed on the potential interactions of marijuana
and perioperative medications.
Field visualization plays a key role in any operation. Marijuana, however, may aect
this. In a literature review published in Poland, Zakrzeska et al. explored how can-
nabinoids and their metabolites and their eects on the receptors CB1, CB2, CBPT
and CBED as well as other systems may impact hemostasis. The authors concluded
that despite the studies that have shown contradictory eects, based on the physi-
ology, it is reasonable to conclude that marijuana could have an anti-hemostatic ef-
fect [59]. Multiple studies have backed up that conclusion. In 1979, Schaeer et al.
reported that cannabis users had a diminished ability for platelet aggregation [60].
This led to further investigations and in 1989, Formukong et al. looked at cannabi-
noidseect on platelet aggregation. The authors found that in both rabbit and hu-
man platelet aggregation that was induced by adenosine diphosphate or epinephrine
was inhibited by cannabinoids in a dose-dependent manner and with cannabidiol
more potent than THC in this eect [61]. Then in 2007, an in vitro coagulation study
showed that marijuana and two of the major cannabinoids, including THC, had an
anticoagulant property and even more so, an antithrombotic eect. In the in vivo
model testing clotting times of lean and obese rats, those treated with cannabis
had clotting times 1.5 to 2 times greater than the controls, thus supporting the results
of the in vitro study [62]. In a follow-up study in 2014, the whole blood of donors
who had consumed cannabis had diminished platelet aggregation. The conclusion
was drawn that endocannabinoid receptor agonists reduce platelet activation as
well as aggregation, and as such might have potential in antithrombotic therapies
[63]. This anticoagulatory eect could counteract the surgeons attempts to create
hemostasis within the operative eld and thus limit visualization.
Yet Zakrzeska also concluded that marijuana use may put certain individuals at risk
for thromboembolism [59], a second issue of surgical concern. Even though an
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intravenous injection of cannabis has been shown to cause a signicant drop in the
platelet count which seems in line with the belief of anticoagulation, it is the mari-
juana components that cause a release of ADP from erythrocyte, leading to platelet
aggregation. This aggregation is the reason behind the reduction in platelet count
[64]. The theory of marijuana use leading to platelet aggregation leads toward sub-
stantiating the conclusion Desbois et al. made in regards to an increased predilection
for myocardial infarctions and arterial disease [19]. Reports of cases similar lead to
Deusch et al.s in vitro study. The cannabinoid receptors CB1 and CB2 were found
on the cell membrane of the human platelet via western blot. Delta-9-
tetrahydrocannabinol, which is the ingredient within cannabis responsible for the
psychological eects, demonstrated the ability to signicantly increase the expres-
sion of glycoprotein IIb-IIIa as well as P-selectin thus increasing the activation of
the human platelet. This ndings lead to the conclusion that THC, through its eects
on the cannabinoid receptors on platelets, may create a prothrombotic setting favor-
ing the development of cardiovascular events [65].
As surgical technique and eld advance, more complicated and potentially painful
procedures are becoming more common practice. Surveying patients indicated
that over 80% experience postoperative pain that was rated as either moderate or se-
vere [66]. This pain can set oa series of physiologic changes that may harm various
systems ranging from cardiovascular to the central nervous system [67], and has
been shown to lengthen hospital stays and time to rst ambulation, impede postop-
erative nursing and physiotherapy, increase healthcare costs, and reduce the patients
satisfaction with the outcome [67]. However, multiple reviews of the available liter-
ature have concluded that appropriate and adequate postoperative analgesia im-
proves recovery, including improving cardiac function and decreasing mortality
and morbidity related to pulmonary function, decreases thrombosis risk, diminishes
the possibility of chronic pain syndrome, and improves overall outcome [68]. Mari-
juana plays a role now in medicine as an analgesic. Prescribed for a number of di-
agnoses, medical marijuana has been shown in over 18 randomized trials to be
both eective and safe in the treatment of chronic pain, with the best evidence being
for neuropathic pain [69]. Investigating the role marijuana plays as an analgesic,
Russo found that due to cannabiss role in multiple pathways, safety, and potential
side eects and benets shown in the clinical trials, marijuana may play a more
important role in pain management when combined with opioids [70]. However,
the appropriate management of marijuana users with opioids postoperatively is
more complicated than these trials suggest. In chronic marijuana users, the periop-
erative narcotic requirements to gain appropriate analgesia were signicantly
increased. Yet despite this increase, patients were more likely to subjectively expe-
rience less pain than those of their non-marijuana using counterparts [71]. Clinically,
this increase materialized in the form of a narcotic requirement twice that of the
average patient of the same height and weight each day over the course of two
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postoperative days [50], demonstrating a potential interaction between marijuana
and opioids which must be taken into account when considering the potential post-
operative complications that may arise from the increased doses of opioids.
In a literature review published in the Journal of Obesity Surgery, Rummel et al.
posed the question of whether or not marijuana use should be a contraindication
to bariatric surgery. In their investigation, the authors determined that there was a
lack of a generalized screening protocol for marijuana use amongst providers and
thus there is no account of a known eect on procedures due to confounders. Yet,
due to the many eects marijuana has on the cardiovascular, pulmonary, immuno-
logic, and central nervous system, the conclusion was drawn that it is fair to hypoth-
esize that cannabis use has the potential to worsen adverse outcomes in the
postoperative period [72]. These potential risks and lack of screening resulted in
the recommendation that practitioners of bariatric surgery should be devoted to as-
sessing controlled and problematic levels of preoperative substance use and take the
time to discuss the potential postoperative risks with patients [73]. However, the
American Association of Clinical Endocrinologists, the Obesity Society, and the
American Society for Metabolic and Bariatric Surgery took the recommendations
one step further by stating that current drug use, including marijuana, should be
treated as exclusionary criterion in the case of bariatric surgery [74]. These recom-
mendations for an elective procedure should potentially be considered in the case of
all elective surgical procedures.
3. Conclusions
After an extensive and comprehensive review of available literature, a fund of
knowledge was found to exist pertaining to the physiological eects of marijuana
as well as the metabolites within, most notably THC and cannabinol. While this in-
formation has been present with 40 years of research, no investigation has taken
place pertaining to patientsmarijuana use and surgical considerations, such as eect
on wound healing, that the piecing together of this data warrants.
The documented evidence of marijuanaseects is of great concern for surgery.
Whether it be the presentation of arrhythmias [10,11,12,13], myocardial infarction
[15,16], stroke [17], pulmonary obstruction [35,36,37] as well as anesthetic con-
cerns [47,48,50] and/or thromboembolus [19,64,65] or bleeding [59,60,61,62,
63], marijuanas multi-system, multi-organ eects are possible confounders to a va-
riety of medical outcomes, let alone surgical. With THC and cannabinoids being
shown to be present for up to 30 days within the fat [5], its potential to aect the
entire operative course in either chronic or acute smokers must be evaluated.
One potential reason behind the lack of or limitation of clinical trials pertaining to
surgical outcomes, including wound cleaning, is due to the most commonly smoked
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drug, tobacco. While this may change in time with marijuana use being legalized in
more states and the potential increase in patients admitting use, the available clinical
trials and cohort studies suer from the current diculties. As there is a relationship
between the smokers of tobacco and those of marijuana, it can also be dicult to
separate out the eects of one from the other. While the marijuana cigarette may
contain more carcinogens [20,22] and equate to more tobacco cigarettes in number
[21], the resultant airway inammation is similar to that of tobacco [26], blurring the
causation line via pathologic examination. Additionally, few studies have elicited in-
formation on the frequency of use of both marijuana and tobacco products as well as
the dierences in amount despite the repetition that exists in the recommendations
for marijuana screening. However, one particular cohort study of just over 1000 pa-
tients was able to separate out the individual acute eects but also the synergistic
eects of tobacco use and marijuana use on the lungs via the use of salbutamol
and incentive spirometry. This study, however, is limited due to relying on patient
self-reporting of lifetime marijuana use [75].
Another possible reason complicating the clinical data on marijuana is the presence
of contradictory reports and trials, most prevalent in the debate on coagulopathy [59,
As cannabis use becomes more prevalent within our society due to the legalization of
both medicinal and recreational cannabis across the country, the lack of data leaves
surgeons without much evidence-based approaches to marijuana management
within the surgical patient population, one in which marijuana users comprise
14% of as of 2003 [34]. While a patients history of marijuana use may be unavoid-
able in the case of emergency surgery, further research is necessary to provide the
needed information to utilize in the time of elective surgical procedures.
Author contribution statement
All authors listed have signicantly contributed to the development and the writing
of this article.
Funding statement
This research did not receive any specic grant from funding agencies in the public,
commercial, or not-for-prot sectors.
Competing interest statement
The authors declare no conict of interest.
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Additional information
No additional information is available for this paper.
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... V předanestetické rozvaze je třeba zohlednit nejzávažnější rizika vyplývající z psychomimetických účinků a z účinků na kardiovaskulární systém. Akutní intoxikace může vyvolat intenzivní úzkost, paranoiu, až skutečnou psychózu a zvyšuje pravděpodobnost agresivního chování při probouzení z anestezie[3][4][5][6]. Psychické i kognitivní poruchy mohou přetrvávat až 24 hodin. ...
... U pacientů, kteří používají konopí kouřením, jsou jeho účinky na dýchací systém podobné účinkům kouření tabáku, jiní autoři předpokládají účinky horší vzhledem k tomu, že konopí se spaluje při vyšší teplotě než tabák (3-4 cigarety s konopím odpovídají účinkem na dýchací systém 20 cigaretám s tabákem)[6]. Specificky je popisován častý výskyt uvulitidy s nebezpečím perioperační obstrukce dýchacích cest[2][3][4][5]. ...
... Ačkoliv kanabinoidy dělají bronchodilataci, během anestezie byly popsány naopak případy bronchokonstrikce, hypersekrece hlenu a obstrukce během umělé plicní ventilace. Kromě toho kanabinoidy mohou při svém metabolismu kompetovat s dalšími látkami využívajícími tytéž cytochromy, takže mohou zvýšit účinek warfarinu a dalších látek ovlivňujících koagulaci, mohou snižovat účinek nesteroidních antiflogistik působením na cyklooxygenázu a ovlivňovat i řadu dalších léků[2][3][4][5][6].Rizikovým faktorem je také kanabinoidy indukovaný hyperemetický syndrom s možností dehydratace a iontové dysbalance[3].Pro výběr anestezie není u osob užívajících konopí žádné zvláštní omezení. Při použití lokoregionálních metod je vhodné se vyhnout kardiotoxickému bupivakainu vzhledem k oběhovým účinkům kanabinoidů. ...
The adverse effects of tobacco use have been well documented, and proper counseling for patients considering surgical procedures who utilize tobacco products have been well established.¹ However, there has been a lack of data and consensus regarding the use of cannabis products in the setting of surgical procedures. There is an assumption that cannabis products are different than tobacco and that the adverse effects of tobacco use would not be seen with cannabis use. The cannabis plant consists of tetrahydrocannabinol (THC) and other cannabinoids, of which the primary one is cannabidiol (CBD).² Smoking marijuana results in the rapid pulmonary absorption of THC and CBD, usually within 15 minutes. Oral ingestion of cannabis has a slower onset of action, typically about 90 minutes. Cannabinoids are lipid-soluble compounds that when ingested are associated with a slow release into the bloodstream and may persist for up to 30 days. This study provides strong evidence that active cannabis and tobacco use will increase the risk of postoperative complications.³ The study was based on the review of 2 global databases that included over 360,000,000 patients. The authors evaluated 3 cohorts, which included tobacco only, cannabis only, as well as the combination of tobacco and cannabis. In the study, the authors demonstrated a significant increase in wound dehiscence (tobacco only, tobacco and cannabis); need for debridement (tobacco only, tobacco and cannabis); surgical site infection (tobacco only, cannabis only, tobacco and cannabis); and need for incision and drainage (tobacco and cannabis). Although tobacco and cannabis products differ, the complications arising from each are very similar in patients who are active users.
The greatly increasing use of medicinal cannabis products as well as the upcoming legalization of cannabis not only require a general re-evaluation of how these substances might be classified as illegal drugs, but also enforce a critical view on the possible consequences that cannabis consumption might have on the anesthesiological strategies applied for surgical procedures. Although high-quality clinical studies are still lacking, several clinical studies meanwhile indicate that an active preoperative cannabis consumption seems to be associated with relevant pathophysiological aspects. Patients who regularly consume high doses of cannabis show an increased risk of cardiovascular and respiratory complications as well as the postoperative nausea and vomitting (PONV) associated with anesthesia. This also applies to relatively young patients. Moreover, the requirements for general anesthetics and analgesics seem to be increased in the context of cannabis consumption, e.g., these patients may require additional efforts when it comes to monitoring the depth of anesthesia and providing a personalized multimodal postoperative pain therapy. It therefore appears to be meaningful to carefully assess and document the extent and duration of the preoperative cannabis consumption during the preoperative assessment. Furthermore, the possibility to perform a preoperative dose reduction of cannabis products in cases with high doses should at least be considered. As the consumption of cannabis is not only increasing in Germany but also worldwide, important future insights will offer a guide towards a safe handling of cannabis in perioperative medicine in the coming years.
Successful surgical management of patients with facial fractures requires a detailed preoperative evaluation and postoperative management that differs from elective surgical patients. This review presents evidence-based recommendations from the surgical and anesthesiology literature that address many of the clinical questions that arise during the perioperative management of this group of patients. Surgeons and anesthesiologists must work together at numerous points and make joint decisions, especially where airway and pain management challenges may arise. The multidisciplinary nature of the decision-making process is emphasized.
Background: Cannabis is the third most used controlled substance in the world. Despite its widespread use, minimal research investigates cannabis usage in patients undergoing facial fracture surgeries. This study aimed to evaluate patterns of postoperative complications related to cannabis and tobacco usage after mandible fracture surgeries. Materials and methods: PearlDiver™, a commercially available healthcare database, was used to identify patients endorsing the use of cannabis, tobacco, or both who underwent mandible fracture surgeries for cross-sectional analysis. The study population was categorized into groups using the Classification of Diseases, 9th revision (ICD-9), ICD-10, and Current Procedural Terminology (CPT) codes. A chi-square analysis was performed to assess the influence of cannabis and tobacco use on postoperative complications. Results: A total of 8288 patients met the inclusion criteria, with 72 patients with cannabis-only usage, 914 patients with cannabis and tobacco usage, 3236 patients with tobacco-only usage, and 4066 in the control group. For patients using only cannabis, there was not an increased risk of developing postoperative complications compared with the control population. Patients with concurrent cannabis and tobacco usage and those with tobacco-only usage had an increased risk of surgical site infection, facial nonunion, facial abscess, debridement, and malocclusion after surgical repair of mandibular facial fracture. Conclusion: Patients with tobacco-only as well as cannabis and tobacco usage had an increased risk of all postoperative complications, except malocclusion, compared with cannabis-only. Based on the results of this study, it is recommended that healthcare providers consider a patient's history of tobacco use when planning and performing surgical treatment for traumatic mandible fractures.
Background Many states have legalized medical cannabis with various reported therapeutic benefits. However, there is little data assessing the effects of cannabis on surgical outcomes. We sought to compare post-operative pancreatic resection complications between cannabis users and non-users. Methods This is a single-center, retrospective review of patients who underwent Whipple or distal pancreatectomy from 1/2017-12/2020. The primary outcome was any in-hospital complication, using Clavien-Dindo. Multivariable regression analysis was performed. Results There were 486 patients who underwent Whipple (n=346, 71.2%) or distal pancreatectomy (n=140, 28.8%). Overall, 21.4% (n=104) reported cannabis use, of whom 80.8% were current users. Cannabis users were younger (60 vs. 66 years, p<0.001), and more likely to have smoked tobacco (p=0.04), but otherwise had similar demographics as non-users. There were 288 (59.3%) patients who developed an in-hospital complication (grade 1-2, 75.3%; grade 3-5, 24.7%). A trend towards increased complications was observed with tobacco smoking (OR 1.33, 95% CI 0.91-1.94, p=0.14), but no association of cannabis use with complications was observed (OR 0.93, 95% CI 0.58-1.47, p=0.74). Discussion A significant proportion of patients undergoing pancreatic resection report cannabis use. These results suggest that there was no association between cannabis use and post-operative complications, future prospective evaluation is warranted.
Purpose: Appropriate preoperative screening techniques are needed to safely provide anesthesia to increasing numbers of cannabis using surgical patients. Design: This was a quasi-experimental quality improvement project. Methods: Preoperative identification of cannabis users by registered nurses (RNs) and certified registered nurse anesthetists (CRNAs) was compared to baseline identification rates. CRNAs' compliance with evidenced base guidelines was recorded. Perioperative medication requirements were recorded and compared between cannabis-users and non-cannabis users. Findings: Identification of cannabis users by CRNAs conducting preanesthetic assessments increased from 4.08% to 14.36% while RN identification improved from 11.22% to 13.81%. Compliance with identification guidelines was 69.2% among CRNAs. There were no differences in anesthetic requirements, complications, or postanesthesia care unit (PACU) length of stay between cannabis users and non-users. Conclusion: Preoperative identification of cannabis users allows for safer, more effective perioperative care by CRNAs, registered nurses, and surgical staff.
Background The past two decades have seen an increase in cannabis use due to both regulatory changes and an interest in potential therapeutic effects of the substance, yet many aspects of the substance and their health implications remain controversial or unclear. Methods In November 2020, the American Society of Regional Anesthesia and Pain Medicine charged the Cannabis Working Group to develop guidelines for the perioperative use of cannabis. The Perioperative Use of Cannabis and Cannabinoids Guidelines Committee was charged with drafting responses to the nine key questions using a modified Delphi method with the overall goal of producing a document focused on the safe management of surgical patients using cannabinoids. A consensus recommendation required ≥75% agreement. Results Nine questions were selected, with 100% consensus achieved on third-round voting. Topics addressed included perioperative screening, postponement of elective surgery, concomitant use of opioid and cannabis perioperatively, implications for parturients, adjustment in anesthetic and analgesics intraoperatively, postoperative monitoring, cannabis use disorder, and postoperative concerns. Surgical patients using cannabinoids are at potential increased risk for negative perioperative outcomes. Conclusions Specific clinical recommendations for perioperative management of cannabis and cannabinoids were successfully created.
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This article reviews recent research on cannabinoid analgesia via the endocannabinoid system and non-receptor mechanisms, as well as randomized clinical trials employing canna- binoids in pain treatment. Tetrahydrocannabinol (THC, Marinol ® ) and nabilone (Cesamet ® ) are currently approved in the United States and other countries, but not for pain indications. Other synthetic cannabinoids, such as ajulemic acid, are in development. Crude herbal cannabis remains illegal in most jurisdictions but is also under investigation. Sativex ® , a cannabis derived oromucosal spray containing equal proportions of THC (partial CB 1 receptor agonist ) and can- nabidiol (CBD, a non-euphoriant, anti-infl ammatory analgesic with CB 1 receptor antagonist and endocannabinoid modulating effects) was approved in Canada in 2005 for treatment of central neuropathic pain in multiple sclerosis, and in 2007 for intractable cancer pain. Numer- ous randomized clinical trials have demonstrated safety and effi cacy for Sativex in central and peripheral neuropathic pain, rheumatoid arthritis and cancer pain. An Investigational New Drug application to conduct advanced clinical trials for cancer pain was approved by the US FDA in January 2006. Cannabinoid analgesics have generally been well tolerated in clinical trials with acceptable adverse event profi les. Their adjunctive addition to the pharmacological armamentarium for treatment of pain shows great promise.
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Elements of the endocannabinoid system (cannabinoid receptors CB1, CB2, CBPT and CBED, endocannabinoids, enzymes involved in the synthesis and metabolism of endocannabinoids) are located on the structures involved in the process of hemostasis. An increasing level of endocannabinoids was also observed in some pathological conditions, which may occur in disorders of hemostasis. At the same time, disconcertingly, there is an increased number of reports about incidents of cardiovascular events in smokers of marijuana. Experimental and clinical studies demonstrated multidirectional, often contradictory, effects of cannabinoids on hemostasis, including effects of the compounds on platelets, vascular endothelium, fibrinolysis and plasma coagulation systems. The mechanisms of action of cannabinoids on homeostasis depend on the cannabinoid receptors CB1, CB2, CBPT and CBED, receptors of other systems stimulated by endocannabinoids, as well as metabolites of endocannabinoids and nitrogen oxide. The range of biological functions of endo- and plant cannabinoids, expanded to include the process of hemostasis, may constitute a condition for their recognition as a new factor responsible for thromboembolism in smokers of marijuana, in pathological disorders with increased levels of endocannabinoids and in individuals with polymorphisms of FAAH C385A and A385A. On the other hand, there are compelling reasons for anti‑hemostatic action of cannabinoids.
Dysregulation of the endogenous lipid mediators endocannabinoids and their G-protein-coupled cannabinoid receptors 1 and 2 (CB1R and CB2R) has been implicated in a variety of cardiovascular pathologies. Activation of CB1R facilitates the development of cardiometabolic disease, whereas activation of CB2R (expressed primarily in immune cells) exerts anti-inflammatory effects. The psychoactive constituent of marijuana, Δ9-tetrahydrocannabinol (THC), is an agonist of both CB1R and CB2R, and exerts its psychoactive and adverse cardiovascular effects through the activation of CB1R in the central nervous and cardiovascular systems. The past decade has seen a nearly tenfold increase in the THC content of marijuana as well as the increased availability of highly potent synthetic cannabinoids for recreational use. These changes have been accompanied by the emergence of serious adverse cardiovascular events, including myocardial infarction, cardiomyopathy, arrhythmias, stroke, and cardiac arrest. In this Review, we summarize the role of the endocannabinoid system in cardiovascular disease, and critically discuss the cardiovascular consequences of marijuana and synthetic cannabinoid use. With the legalization of marijuana for medicinal purposes and/or recreational use in many countries, physicians should be alert to the possibility that the use of marijuana or its potent synthetic analogues might be the underlying cause of severe cardiovascular events and pathologies.
It is critically important to identify all factors that may play a role in the recent increase of the incidence of stroke among the young population. Considering the worldwide use of cannabinoids (cannabis and synthetic cannabinoids), the recent legalization of their consumption in some countries, and their supposed involvement in cardiovascular events, we evaluated their role in the occurrence of neurovascular complications among the young. Ninety-eight patients were described in the literature as having a cannabinoids-related stroke (85 after cannabis use and 13 after synthetic cannabinoids). The distribution by type of stroke was as follows: 4 patients with an undetermined type of stroke, 85 with an ischemic stroke and/or a transient ischemic attack, and 9 with a hemorrhagic stroke. The mean age of patients was 32.3 ± 11.8 years (range 15–63), and the majority of them were male with a sex ratio of 3.7:1. Cannabis was often smoked with tobacco in 66% of cases. Most of the patients with cannabinoids-related strokes were chronic cannabis users in 81% of cases, and for 18% of them, there was a recent increase of the amount of cannabis consumption during the days before the occurrence of stroke. Even if the prognosis of stroke was globally favorable in 46% of cases, with no or few sequelae, 5 patients died after the neurovascular event. One striking element reported in the majority of the reports was a temporal relationship between cannabinoids use, whether natural or synthetic, and the occurrence of stroke. However, a temporal correlation does not mean causation, and other factors may be involved. Cannabis may be considered as a risk factor of stroke until research shows evidence of an underlying mechanism that, alone or in association with others, contributes to the development of stroke. As of today, reversible cerebral vasoconstriction triggered by cannabinoids use may be a convincing mechanism of stroke in 27% of cases. Indeed, despite the widespread use of cannabinoids, the low frequency of neurovascular complications after their use may be due to a genetic predisposition to their neurovascular toxicity in some individuals. Further studies should focus on this point. More importantly however, this low frequency may be underestimated because the drug consumption may not be systematically researched, neither by questioning nor by laboratory screening. Besides this vascular role of cannabinoids in the occurrence of stroke, a cellular effect of cannabis on brain mitochondria was recently suggested in an experimental study. One of the mechanisms involved in young cannabis users with stroke may be the generation of reactive oxygen species leading to an oxidative stress, which is a known mechanism in stroke in humans. It is useful to inform the young population about the real potential risk of using cannabinoids. We suggest to systematically ask all young adults with stroke about their drug consumption including cannabinoids, to screen urine for cannabis or to include a specific diagnostic test to detect synthetic cannabinoids, and to obtain non-invasive intracranial arterial investigations (i.e. CT-angiography or cerebral MRA) in order to search for cerebral vasoconstriction. However, several questions remained unresolved and further research is still needed to assess the pathophysiological mechanisms involved in young cannabinoids users with stroke. This article is part of a Special Issue entitled “Cannabinoids and Epilepsy”.
Background: Patients with asthma are thought to be at high risk for pulmonary complications to develop during the perioperative period, and these complications may lead to serious morbidity, Existing medical records were reviewed to determine the frequency of and risk factors for perioperative pulmonary complications in a cohort of residents of Rochester, Minnesota, who had asthma and who underwent anesthesia and surgery at the Mayo Clinic in Rochester. Methods: Medical records were reviewed for all residents of Rochester, Minnesota, who were initially diagnosed as having definite asthma according to strict criteria from 1 January 1964 through 31 December 1983 who subsequently had at least one surgical procedure involving a general anesthetic or central neuroaxis block at the Mayo Clinic (n = 706). Results: Bronchospasm was documented in the perioperative records of 12 patients [1.7% [exact 95% confidence interval, 0.9 to 3%]). Postoperative respiratory failure developed in one of these patients. Laryngospasm developed in two additional patients during operation. All episodes of bronchospasm and laryngospasm in the immediate perioperative period were treated successfully, No episodes of pneumothorax, pneumonia, or death in the hospital were noted. For univariate analysis, characteristics associated with complications included the recent use of antiasthmatic drugs, recent asthma symptoms, and recent therapy in a medical facility for asthma, Patients in whom complications developed were significantly older at diagnosis and at surgery. Conclusions: The frequency of perioperative bronchospasm and laryngospasm was surprisingly low in this cohort of persons with asthma, These complications did not lead to severe respiratory outcomes in most patients. The frequency of com plications was increased in older patients and in those with active asthma.
Marijuana (Cannabis sativa I.) has become the second most widely used smoke product in the Western World1-2-3-4. Marijuana smoke, however, is inhaled in significantly lower doses than tobacco smoke and its effect is predominantly psychotomimetic with some acute toxic side effects. Nevertheless, information as to the carcinogenicity of this inhalant is needed. Since most marijuana smokers are also cigarette smokers, it needs furthermore to be determined whether marijuana smoke can potentiate the carcinogenic effect of tobacco smoke.
This case report describes the anaesthetic management of a patient addicted to Bhang(cannabis) for 20 years. Cannabis use has implication in the anaesthetic management of a patient because of its effects on the cardiovascular system, respiratory system, and central nervous system and its interaction with anaesthetic drugs.
Thirty-one American soldiers who smoked enormous quantities of illicit hashish for several months temporally related a number of medical effects to their habit. Their ailments were principally respiratory and included bronchitis, sinusitis, asthma, and rhinopharyngitis. Irritation of the respiratory tract by hashish smoke appeared to be responsible. Uvular edema is reported as a useful physical sign in the evaluation of the suspected user of hashish.