|
|
||||||||
a Division of General Thoracic Surgery, University Hospital Berne, Switzerland
b Department of Surgery, Otto von Guericke University Hospital, Magdeburg, Germany
Received 2 April 2007; received in revised form 5 July 2007; accepted 23 July 2007.
* Corresponding author. Address: Division of General Thoracic Surgery, University Hospital Berne, Berne, Switzerland. Tel.: +41 316 322111; fax: +41 316322327. (Email: ralph.schmid{at}insel.ch).
| Abstract |
|---|
|
|
|---|
Abbreviations: SSP = secondary spontaneous pneumothorax FEV1 = first second forced expiratory volume VC = vital capacity VATS = video-assisted thoracic surgery CRP = C-reactive proteins
Key Words: Pneumothorax Cannabis Lung emphysema
| 1. Introduction |
|---|
|
|
|---|
Marijuana smoking peaked in 1979 and decreased continuously thereafter until the early 1990s. Since then, according to a recently published national survey on substance abuse in the United States, prevalence of marijuana smoking has increased continuously in high school and college students, as well as in young adults aged 19–32 years. In 1999 prevalence (use within the past month) was 23% in high school seniors, 19% in college students, and 15% in young adults. Daily use was reported by 6.0% of high school students, 4.0% of college students, and 4.4% of young adults [1]. Similarly, the number of the 14–15-year-olds who tried cannabis rose from 19% to 29% in boys and 18% to 25% in girls in the UK from 1999 to 2001 [2]. These numbers are comparable with the ones in countries like The Netherlands or Switzerland, which have a more liberal drug policy. In a large survey on health in Switzerland in 2002, 19.5% of the population between 15 and 64 years had experience with cannabis products of which 18% were between 15 and 34 years old. 4.6% declared consumption on a regular basis and one-half of them at least once a week. The overall consumption in the Swiss population increased from 16.3% of the 15–39-year-olds in 1992 to 27.7% in 2002 [3]. The annual production of cannabis in Switzerland is thought to be 200 tons. In the editorial in the British Journal of Medicine by Henry et al. the number of cannabis smokers in the UK was estimated to be 3.2 millions [2]. The impact of cannabis on the health of the general population is most probably underestimated.
| 2. Patients and methods |
|---|
|
|
|---|
2.2 Diagnosis and management
After admission, all patients underwent clinical examination and standard laboratory examinations. Not all examinations could be performed on all patients due to suboptimal compliance. A chest X-ray was performed and a 24F chest drain was inserted under local anesthesia. Serum
1-antitrypsin levels were measured in 16 patients in group I, 5 patients in group II, and 7 patients in group III. CT-scan of the chest could be performed in 15 patients in group I, 74 patients in group II, and 59 patients in group III. Lung function was done in 12 patients in group I, 70 patients in group II, and 62 patients in group III.
2.3 Surgical treatment
In group I, surgical treatment for the prevention of recurrent pneumothorax by VATS was done in 15 patients. Two refused surgery and were treated with chest tube insertion only. In group II, VATS was done in 65 patients (5 patients had the first episode, 58 patients had the second episode, and 2 patients had recurrence after previous VATS). In group III, VATS was done in 50 patients (3 patients had pneumothorax for the first time, 46 patients had the second episode, and 1 patient had recurrence after previous VATS). In all groups, the surgical procedures using VATS for bullectomy and/or resection of the apex (Endo GIA 45, Ethicon Endosurgery, Cincinnati OH) in addition to pleural abrasion were performed. For bullectomy done mostly in group I, 4–6 cartridges have been used. In case of apex resection 1–3 cartridges were needed. Pleura abrasion over the upper five ribs was done in all first or second episode of pneumothorax. In case of recurrence after VATS, pleurectomy was performed.
| 3. Results |
|---|
|
|
|---|
In group I, all but one patient had an uneventful medical history. This patient had been previously diagnosed with emphysema on a routine chest X-ray by his family doctor, but no treatment was necessary. No patient was on any regular medication. The median BMI was 19.2 kg/m2 (range 16.5–28 kg/m2).
Marijuana consumption on a daily basis was noted in 16 patients (median 6 joints/day), 1 patient smoked marijuana only three times per week and did not smoke cigarettes. All other patients had additional nicotine abuse (mean 7 pack years, range 3–25 pack years). The mean duration of marijuana smoking was 8.8 years (range 3–20 years). In all patients it was shorter than the duration of tobacco smoking (11.6 years, range 4–23 years). Four patients reported a sporadic cocaine use, one LSD over 3 years, and one had sporadic heroin abuse. In group II, 3 patients had known allergic reaction, 1 patient had bronchial asthma, and 74 patients smoked tobacco for 13.4 years. In group III, no medical history was known; 6 smoked marijuana daily for a mean of 3.2 years, and 62 smoked tobacco for 14 years.
3.2 Physical examination
Physical examination and review of systems did not reveal any particular findings except the typical signs of pneumothorax and/or emphysema with no significant difference in all groups.
3.3 Laboratory findings
Routine laboratory did not show any pathological findings, except in one patient who had elevated leucocytes and CRP values due to an infected bulla. The measurements of
1-antitrypsin serum levels were in the normal range with a median of 1.5 g/l (normal values 0.83–1.99 g/l). One patient had a borderline value in group I, two patients in group II, and one patient in group III.
3.4 Lung function
The overall pulmonary function of the 12 patients who agreed to undergo lung function testing was normal with a median FEV1 of 4.5 l (mean 3.8 l, range 2.2–5.0 l) and a median FVC of 5.7 l (mean 4.9 l, range 3.9–6.5 l). Only two of these patients had reduced FEV1 of the predicted 31% and 33% (1.2 and 1.7 l) and only one of them had FVC of 2.5 l (59%). In all other patients the values were above the predicted 89%. The overall pulmonary function performed in 70 patients in group II and in 62 patients in group III showed no significant difference to group I (p
= 0.062).
3.5 Radiological findings
Chest X-ray was done in all patients; CT-scan performed in 88% (n
= 15) in group I, in 85% (n
= 72) in group II, and in 79% (n
= 59) in group III has been examined by our radiologist. Similar findings with different severity of peripheral emphysema and apical bullae were noted in all patients in group I (Fig. 1A and B, Fig. 2A and B). The distribution of the emphysema was homogenous in two patients with predominance in the upper fields. The bullae varied in size from 0.3 cm to 12 cm. In one patient a fluid level in a bulla was noted, indicating infection. In three patients the upper lobes were almost completely replaced by large bullae. On the other hand, there was no lung emphysema reported in the other two groups (p
= 0.014), apart from very small bullae
1 cm in diameter at the apex of the lung in 84% in group II and 89% in group III. These small bullae were more on the right side (p
= 0.12).
|
|
|
| 4. Discussion |
|---|
|
|
|---|
The risk of developing pneumothorax after tobacco smoking or alkaloid cocaine consumption is described [4,5]. A few reports of pneumothorax or pneumomediastinum following combined use of marijuana, heroine, or cocaine have been published [6–9]. Recently, a bilateral spontaneous pneumothorax was, however, reported in a 23-year-old cannabis smoker with normal lung parenchyma in the CT-scan [10]. But these reports describe single and supposedly rare cases.
Cannabis has been used over five millennia for the treatment of many conditions including pain, inflammation, neuralgia, migraine, and dysmenorrhea. It has also been used as an anticonvulsant, muscle relaxant, and for restlessness and anxiety in terminal illness [11,12]. In the early 1970s it was deemed to be of little medical use and was removed from most medication lists. Thereafter, studies have demonstrated a bronchodilator response as a physiological short-term effect of inhaled marijuana. This may be attributed to the pharmacologic effect of
9-tetrahydrocannabinol [13,14] and the stimulation of the cannabinoid-1 receptor on postganglionic parasympathetic nerve endings on airway smooth muscle, leading to inhibition of acetylcholine release [15]. Some known consequences of habitual marijuana smoking include an increased prevalence of chronic cough, sputum production, and wheeze, as well as a higher frequency of acute bronchitis [16–18]. In addition, the risk for myocardial infarction seems to be increased by 4.2 times within an hour after smoking cannabis [2] and the risk for psychosis is increased especially in young adults with a predisposition [19].
Interestingly enough the CT-scan performed in 72 patients in group II and in 59 patients in group III showed only small bullae (under 1 cm in diameter) at the apex with no signs of emphysema of the lung, even in patients who smoked marijuana over a period of 3 years in group III. We oppose that the period of marijuana smoking is an important factor in the development of lung emphysema in these patients. There was no significant difference in the length of the thoracic drainage or in the length of hospital stay between all groups. The rate of recurrence after VATS was not significantly higher in patients with secondary pneumothorax who smoked marijuana.
In a small case series of four patients, three of them from West India with significant exposure to marijuana, the authors describe multiple bullae in the upper lung fields and little parenchymal lung disease elsewhere. As three of these patients had limited tobacco use, those authors concluded that marijuana smoking is the reason for the parenchymal changes, possibly accelerated by tobacco smoking [20]. In contrast, we observed a significant lung change in patients who smoked marijuana for a longer period than 3 years, as well as a homogeneous distribution of emphysema in this series, unlikely to be tobacco emphysema, the so far largest single-center series from a western country, but a predominant upper lobe emphysema was noticed in two patients, which may confirm the findings by other authors as well.
In western countries, the condition seems to be much more frequent. Based on our observations and the prevalence of cannabis smoking in developed countries, we propose to introduce the term joint years (joints/day times years of abuse) to assess the severity of the exposure, as it seems that one joint per day is equivalent to at least to one packet of cigarettes per day.
Subjectively, these young patients were asymptomatic and most of them still had normal lung volumes. Therefore, they only consulted a doctor when the pneumothorax occurred.
The increase of young patients with emphysema, associated with an increase in cannabis smoking in young adults in many countries, may create major health problems in future with a strong medical, financial, and ethical impact, as a number of these patients may be severely handicapped or even end up as lung transplant candidates. The public awareness of the health hazards by cannabis smoking has to be increased (Table 1 ).
|
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
A. S. Reece Severe multisystem dysfunction in a case of high level exposure to smoked cannabis BMJ Case Reports, September 2, 2009; 2009(sep02_1): bcr0820080798 - bcr0820080798. [Abstract] [Full Text] |
||||
![]() |
R. A. Schmid and M. Beshay Reply to Fiorello et al. Eur. J. Cardiothorac. Surg., September 1, 2008; 34(3): 707 - 707. [Full Text] [PDF] |
||||
![]() |
A. Fiorello, G. Vicidomini, and M. Santini Marijuana smokers and lung bullae Eur. J. Cardiothorac. Surg., September 1, 2008; 34(3): 706 - 707. [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |