Dear Editor,

There is paucity of data with regards to the management of primary and secondary spontaneous pneumothorax.

A study was conducted to evaluate whether patients with either primary or secondary spontaneous pneumothorax were managed according to current British Thoracic Society guidelines.

56 consecutive patients with spontaneous pneumothorax were assessed over a 12-month period. In patients with primary spontaneous pneumothorax, 84% were inappropriately managed with intercostal drain insertion. 79% of these patients merely required simple aspiration and 5% warranted observation alone. For patients with secondary spontaneous pneumothorax, 50% were incorrectly managed with simple aspiration when intercostal drain insertion was required. Complications occurred in 32% of patients who had intercostal drain insertion. 77% and 85% of patients with primary and secondary spontaneous pneumothorax respectively were referred to a chest physician regardless of outcome. The mean hospital stay for patients with primary and secondary spontaneous pneumothorax was 4 and 22 days respectively.

The vast majority of patients with primary spontaneous pneumothorax were needlessly exposed to intercostal drain insertion. Implementation of the British Thoracic Society guidelines is crucial in order to avoid unnecessary patient discomfort and procedure related complications. It should also reduce the number of inappropriate referrals to a chest physician.

Prashant S Borade, MB, BS, MD
Catherine I D Ludwig, BChir, MB
D Anthony Promnitz, MB, BCh, FRCP
Daniel K C Lee, MB, BCh, MRCP, MD

Department of Respiratory Medicine
Ipswich Hospital
Heath Road
Ipswich
IP4 5PD
Suffolk
United Kingdom

Dear Editor

The British Thoracic Society (BTS) guidelines for the management of primary spontaneous pneumothorax (PSP) recommend simple aspiration as the first line treatment for all cases of PSP requiring intervention.[1] However, studies in the UK have shown that compliance is poor, and that simple aspiration is under-utilised.[2,3] Henry et al suggested that poor compliance may be due to an unwillingness to aspirate.[1] Medical staff tends to have concerns over the increased likelihood of failure of simple aspiration for larger pneumothoraces. But are these concerns actually justified?

We showed, in a study recently published, that larger size of pneumothorax is significantly associated with failed aspiration.[4] We retrospectively studied 91 consecutive cases of PSP treated by simple aspiration. All cases were treated at the emergency department of an university teaching hospital in Hong Kong, China, over a two-year period. Our protocol had closely followed the BTS guidelines.[5] The overall success rate was 50.5%. Failed cases had significantly larger sizes of pneumothorax (p <_0.0005. furthermore="furthermore" pneumothorax="pneumothorax" size="size"> 40% was significantly associated with failure (p <_0.005. in="in" a="a" multivariate="multivariate" analysis="analysis" pneumothorax="pneumothorax" size="size" _="_">40%¡¦ compared to size ¡¥21-39%¡¦ independently predicted failure, with an odds ratio of 8.88 (95% CI, 2.49 to 31.63). The success rate for patients with pneumothorax size 40% or larger was only 15.4%.

Based on evidence from this study, our guidelines for the management of PSP have been revised. For patients with pneumothorax size 40% or above, simple aspiration is no longer the first line treatment, and chest tube drainage is the preferred modality.

References

(1) Henry M, Arnold T, Harvey J. BTS guidelines for the management of spontaneous pneumothorax. Thorax. 2003;58(Suppl II):ii39-ii52.

(2) Soulsby T. British Thoracic Society guidelines for the management of spontaneous pneumothorax: do we comply with them and do they work? J Accid Emerg Med. 1998; 15(5):317-21.

(3) Mendis D, El-Shanawany T, Mathur A, et al. Management of spontaneous pneumothorax: are British Thoracic Society guidelines being followed? Postgrad Med J. 2002;78:80-84.

(4) Chan SSW, Lam PKW. Simple aspiration as initial treatment for primary spontaneous pneumothorax: Results of 91 consecutive cases. J Emerg Med. 2005;28:133-138.

(5) Chan SSW. Current opinions and practices in the treatment of spontaneous pneumothorax. J Accid Emerg Med. 2000;17:165-169.

Dear Editor

We thank Dr Chan for his further reponse 'error in citation' to the recently published BTS guidelines for the management of spontaneous pneumothorax.[1] Dr Chan has pointed out that our statement in a previous correspondence to him, that a 2cms rim of pneumothorax was a clear indication for use of an intercostal chest drain, was supported by the recent ACCP Delphi consensus document [2] is a error in citation is technically correct. The evidence for this statement is supported in the BTS document by a references also qouted in our previous reply to him later in that paragraph and again below. We recommended the use of the '2 cm rule' in secondary spontaneous pneumothoraces only and not in primary pneumothoraces. As pointed out in the previous correspondence 2 cm will usually (but not always) correspond to a pneumothorax of >50% and these tend not to respond to simple aspiration in patients with secondary pneumothoraces. The same evidence is not available for primary pneumothoraces. As Dr Chan will be aware the two sets of guidlelines quoted were arrived at by totally different means. The delphi document was arrived at by consensus of many specialists, whereas the BTS guidelines were arrived at by review of the published evidence and in the absence of evidence on which to base recommendations, a consensus of the BTS standards of care committee made recommendations. It is not therefore surprising that there are differences between the various sets of guidelines.

References

(1) Henry MT, Arnold T, Harvey J. BTS guidelines for the management of spontaneous pneumothorax. Thorax 2003; 58: 39ii-52ii.

(2) Baumann MH, Strange C, Heffner JE, et al. Management of spontaneous pneumothorax. An American College of Chest Physicians Delphi Consensus Statement. Chest 2001; 119: 590-602.

(3) Archer GJ, Hamilton AAD, Upadhyag R, et al. Results of simple aspiration of pneumothoraces. Br J Dis Chest 1985; 79: 177-182. III

Dear Editor

We thank Dr Ng for his comments on the recently published guidelines on the management of spontaneous pneumothorax.[1] Dr Ng points out that recurrence rates for pneumothorax after VATS preventative procedures were lower than those quoted in the guidelines. It should be pointed out that in the multiple drafts of this document, it was recognised that recurrence rates after VATs were falling and that further improvements in these figures were likely as operator experience improved. This was recognised within the guidlines. It is fully expected that as experience and provision of services impprove, VATS will replace open thoracotomy for treatment of recurrent pneumothoraces. In response to Dr Ngs second points regarding surgical treatment of tension pneumothoraces and hugh bullae, the guidelines obviously could not take into account every possible clinical scenario. As far as we are aware there is no evidence to suggest that tension pneumothoraces are more likely to recur than 'non-tension' spontaneous pneumothoraces. This does not mean of course that an individual physician should not decide that the clinical risk in an individual patient either from rupture of a hugh bulla or recurrence of a tension pneumothorax shouldn't warrent surgical intervention.

Reference

(1). Henry MT, Arnold A, Harvey J. BTS guidelines for the management of spontaneous pneumothorax. Thorax 2003; 58: 39ii-52ii.

Dear Editor

I am grateful for Dr Henry's reply and further comments on 4 September, 2003.[1] Dr Henry stated that the use of '2 cm' correlating to '50%' as an indication for chest tube drainage in secondary spontaneous pneumothorax was supported by evidence, and that this had become a clear and unambiguous guideline. However, the evidence cited [2] was a 'consensus statement' by the American College of Chest Physicians, that large pneumothoraces should be treated with chest tube drainage. (There is no mention of the figure of 50% in that statement).

Furthermore, in the same consensus, we do note areas of inconsistency with the British guidelines.
1. A distinctly different method of size estimation (as Dr Henry correctly pointed out)
2. The use of chest tube drainage not only for large secondary spontaneous pneumothoraces, but also for large primary spontaneous pneumothoraces.

References

(1) Henry MT. Author's Reply [electronic response to BTS guidelines for the management of spontaneous pneumothorax ] thoraxjnl.com 2003 http://thorax.bmjjournals.com/cgi/eletters/58/suppl_2/ii39#83

(2) Baumann MH, Strange C, Heffner JE, et al. Management of spontaneous pneumothorax. An American College of Chest Physicians Delphi Consensus Statement. Chest 2001;119: 590-602.

Dear Editor

We thank Dr Chan for his comments relating to the recently published guidelines for the diagnosis and management of spontaneous pneumothorces.[1] Dr Chan raises the contentious issue of estimation of the size of a pneumothorax from a plain chest radiograph. We have attempted to use a variation of the method of Axel based on the largest distance from the chest wall to the pleural line and using the assumption that because volume of the lung and the hemi-thorax are roughly proportional to the cube of their diameters, the volume of pneumothorax can be estimated by measuring an average diameter of the lung and the hemithorax, cubing these diameters and finding the ratios.[2]

As Dr Chan rightly points out this is not an exact science as the lungs have a propensity not to maintain a constant shape when they collapse. CT of thorax, when compared with plain radiograph, gives a more accurate estimate of the volume of the pneumothorax. However, while CT may be the only way to give an exact estimate of pneumothorax volume and pattern of lung collapse, it is not often feasible in the emergency room. The correlation co-efficient between CT and plain radiograph is 0.71, p <_0.01.3 thus="thus" while="while" cxr="cxr" is="is" not="not" as="as" effective="effective" ct="ct" it="it" does="does" still="still" provide="provide" a="a" useful="useful" and="and" reasonably="reasonably" accurate="accurate" estimate="estimate" of="of" pneumothorax="pneumothorax" size="size" in="in" most="most" cases="cases" using="using" the="the" method="method" outlined="outlined" current="current" guidelines.="guidelines." we="we" suggest="suggest" that="that" guideline="guideline" an="an" improvement="improvement" on="on" _1993="_1993" guidelines="guidelines" which="which" tended="tended" to="to" underestimate="underestimate" potentially="potentially" importance="importance" pneumothorax.="pneumothorax." choosing="choosing" distance="distance" _2="_2" cms="cms" above="above" volume="volume" usually="usually" _50="_50" gives="gives" emergency="emergency" room="room" physician="physician" easy="easy" use="use" fairly="fairly" reliable="reliable" adhere="adhere" to.="to." has="has" been="been" shown="shown" secondary="secondary" pneumothoraces="pneumothoraces" this="this" are="are" unlikely="unlikely" respond="respond" simple="simple" aspiration="aspiration" will="will" hopefully="hopefully" guidance="guidance" patients="patients" treat="treat" with="with" intercostals="intercostals" tube="tube" drainage.4="drainage.4" supported="supported" by="by" evidence="evidence" now="now" clear="clear" unambiguous="unambiguous" guideline.="guideline." also="also" hope="hope" suggesting="suggesting" _="_" _2cms="_2cms" depth="depth" should="should" be="be" aspirated="aspirated" may="may" reduce="reduce" number="number" needle="needle" injuries="injuries" lung="lung" parenchyma="parenchyma" would="would" have="have" much="much" greater="greater" approximation="approximation" chest="chest" wall="wall" primary="primary" spontaneous="spontaneous" cm="cm" depth.="depth." p="p"> As Dr Chan points out the American College of Chest Physicians have suggested a different arbitrary system for estimating pneumothorax size suggesting that ‘small’ pneumothoraces were defined by distances <3 cms from apex to cupula of lung and ‘large’ pneumothoraces had distances > 3cms.[5] This seems to have been arbitrarily defined and we are not provided with evidence to support these measurements. Several authors have suggested different distances ranging from 1-4 cms on plain radiograph or more complex equations depending on distances from the pleural line to chest wall at three separate distances or even routine use of CT incorporating even more complex mathematics.[6,7] Dr Chan comments on the lack of evidence regarding CXR classification – we have completed an analysis of the CXR appearances in spontaneous pneumothorax, relating them to the various guidelines, and submitted it as an abstract for the winter meeting of the British Thoracic Society. Bearing in mind that the guidelines are primarily prepared for use by relatively inexperienced and non-specialist junior medical staff, who often have to make management decisions in the middle of the night, we would suggest that the BTS guidelines have combined a fairly robust and accurate scientific approach with an easy to interpret and implement guideline to estimate and treat spontaneous pneumothoraces. Finally, we would again take the opportunity to stress that no matter what the size of a pneumothorax, the decision as to what constitutes appropriate treatment depends not just on the size of a pneumothorax on a chest radiograph, but more importantly, on the clinical status of the patient.

References

(1) Henry M, Arnold T, Harvey J. BTS guidelines for the management of spontaneous pneumothorax. Thorax 2003; 58(Suppl 11):ii39-52.

(2) Axel L. A simple way to estimate the size of pneumothoraces. Invest Radiol 1981;105:1147-1150.

(3) Engdahl O, Toft T, Boe J. Chest radiograph - a poor method for determining the size of a pneumothorax. Chest 1993;103:26-29.

(4) Baumann MH, Strange C, Heffner JE, et al. Management of spontaneous pneumothorax. An American College of Chest Physicians Delphi Consensus Statement. Chest 2001; 119: 590-602.

(5) Archer GJ, Hamilton AAD, Upadhyag R, et al. Results of simple aspiration of pneumothoraces. Br J Dis Chest 1985; 79:177-182.

(6) Collins CD, Lopez A, Mathie A, Wood V, Jackson JE, Roddie ME. Quantification of Pneumothorax size on chest radiographs using intrapleural distances: Regression analysis based on volume measurements from helical CT. Am J Radiol 1995;165:1127-1130.

Dear Editor

"It is not the strongest of the species that survives, nor the most intelligent, it is the one most adaptable to change."
Charles Darwin (1809-1882)

The article "BTS guidelines for the management of spontaneous pneumothorax" by Henry et al.[1] has recently stimulated some discussion among our respiratory physicians and thoracic surgeons.

We found it interesting that the authors quoted the recurrence rates of pneumothorax after VATS (Video Assisted Thoracic Surgery) to be between 5-10%. Recently, numerous large series from around the world have shown recurrence rates of primary spontaneous pneumothorax after VATS bullectomy combined with surgical pleurodesis, to be in the range of 1.7-5.7%. [2,3] Although the recurrence rates from VATS may be marginally higher than open procedure, nevertheless, the benefit to the patient of shorter postoperative hospital stay, less post-operative pain and better pulmonary gas exchange in the postoperative period should be balanced. Furthermore, we found in a study patients undergoing VATS to have significantly less shoulder dysfunction and pain medication requirements in the early post- operative period when compared with posterolateral thoracotomy.[4] Whether VATS can be “established as being superior to thoracotomy” will in part be decided by our patients and become clearer with future trials.

With the lowered morbidity and proven safety of VATS, even for elderly and paediatric population,[2] the old surgical algorithms developed based on the morbidity of thoracotomy should be re-evaluated.[5] We feel there are two additional conditions that warrant inclusion in the list for “accepted indication for operative intervention”. Firstly, patients presenting with the life-threatening condition of tension pneumothorax, even for the first time, should be considered for VATS because of the potential grave consequences of its recurrence. Secondly, presence of radiologically demonstrated huge bulla associated with spontaneous pneumothorax should be an indication for VATS because of increase risk of pneumothorax recurrence. In addition, the huge bulla may continue to expand and impair lung function by causing compression of adjacent healthy lung tissue, and can be manifestation of lung carcinoma or a focus for recurrent infection.[2,6]

References

(1) M Henry, T Arnold and J Harvey. BTS guidelines for the management of spontaneous pneumothorax. Thorax 2003;58:ii39

(2) Ng CSH, Wan S, Lee TW, Wan IYP, Arifi A, Yim APC. Video-assisted thoracic surgery in spontaneous pneumothorax. Canadian Resp J 2002;9:122- 127.

(3) Yim APC, Ng CSH. Thoracoscopic management of spontaneous pneumothorax. Curr Opin Pulm Med 2001;7:210-4.

(4) Li WWL, Lee RLM, Lee TW, Ng CSH, Sihoe ADL, Wan IYP, Arifi AA, Yim APC. The impact of thoracic surgical access on early shoulder function: video-assisted thoracic surgery versus posterolateral thoracotomy. Eur J Cardiothorac Surg 2003;23:390-6

(5) Yim APC. Video assisted thoracoscopic surgery (VATS) in Asia: Its impact and implications. Aust NZ J Med 1997;27:156-9

(6) Ng CSH, Sihoe ADL, Wan S, Lee TW, Arifi AA, Yim APC. Giant pulmonary bulla. Can Respir J 2001;8:369-71

Dear Editor

I read, with interest, the new BTS guidelines for the management of spontaneous pneumothorax.[1] Arnold and colleagues acknowledged that the plain radiograph was a poor method of quantifying the size of a pneumothorax, yet then went on to use one radiographic method of assessment to estimate the degree of lung collapse.

Under the new guidelines, the size of a pneumothorax is divided into "small" or "large" depending on the presence of a visible rim of "< 2cm" or "> or = 2cm" between the lung margin and the chest wall. The authors then explained in detail how these distances could be used to estimate the percentage of lung collapse. A schematic figure was even used to illustrate the calculations. However, the method employed by the authors (the method of Axel),[2] like most other methods, have been shown to be a poor method for determining pneumothorax size under clinical conditions.[3]

I do not see any evidence that the new classification is in any way better than the old one. The calculations based on the distance of the rim correlated poorly to the actual size of pneumothorax.[3] The "2 cm" used is an arbitrary figure. It is even more confusing to have the American guidelines use another arbitrary system of classification.[4] In spontaneous pneumothorax, practitioners should at least agree on the same classification system of size before they continue to debate about what is the best option of treatment.

References

(1) Henry M, Arnold T, Harvey J, et al. BTS guidelines for the management of spontaneous pneumothorax. Thorax 2003;58(Suppl II):ii39-ii52.

(2) Axwl L. A simple way to estimate the size of a pneumothorax. Invest Radiol 1981;16:165-166.

(3) Engdahl O, Toft T, Boe J. Chest radiograph - a poor method for determining the size of a pneumothorax. Chest 1993;103:26-29.

(4) Baumann MH, Strange C, Heffner JE, et al. Management of spontaneous pneumothorax: an American College of Chest Physicians Delphi Consensus Statement. Chest 2001;119:590-602