Although there is no agreement on the optimal treatment of patients presenting with a first episode of primary spontaneous pneumothorax, the majority of physicians prefer chest tube drainage for air evacuation. Manual aspiration of air has been proposed by some, but lack of sound comparative data and safety data has limited its use. In this first randomized, prospective, multicenter pilot study, 60 patients with a first episode of primary spontaneous pneumothorax were randomly allocated to manual aspiration (n = 27) or chest tube drainage (n = 33). Immediate success was obtained in 16 out of 27 (59.3%) in the manual aspiration group, and in 21 out of 33 (63.6%) in the chest tube drainage group (p = 0.9). One-week success rates were 25 out of 27 (93%) in the intention-to-treat manual aspiration group and 28 out of 33 (85%) in the chest tube drainage group (p = 0.4). Fourteen of 27 manual aspiration patients (52%) were hospitalized, versus 100% of the chest tube drainage patients (p < 0.0001). Recurrence rates with at least 1-year follow-up were 7 out of 26 (26%) in the manual aspiration group, and 9 out of 33 (27.3%) in the chest tube drainage group (p = 0.9). There were no complications associated with manual aspiration. Although statistical power is insufficient to formally confirm therapeutic equality, this pilot study suggests that in first episodes of primary spontaneous pneumothorax, manual aspiration seems equally effective as chest tube drainage and is safe, well tolerated, and feasible as an outpatient procedure in the majority of patients.
Primary spontaneous pneumothorax is defined as a spontaneously occurring pneumothorax in a person without clinically apparent underlying lung disease (1). Primary spontaneous pneumothorax is believed to be caused by a process of distal airway-inflammation and -obstruction, secondary to a variety of external (e.g., cigarette smoking) (2) and internal factors (e.g., bronchial abnormalities) (3). Distal airway obstruction may lead to the development of emphysema-like changes (e.g., blebs), the rupture of which may lead to a visceral pleural air leak (1) or to the development of direct visceral pores (4) or to mediastinal pleural leaks (5). Recurrence rates after a first episode of primary spontaneous pneumothorax, managed with nonpleurodetic techniques, such as simple observation, manual aspiration, or chest tube drainage, vary from 16 to 52%, averaging 30% (6).
Treatment choice for a first episode of primary spontaneous pneumothorax is influenced by the clinical presentation; the size of the pneumothorax; the assessment of the recurrence risk; and the professional/occupational activities of the patient, patient preference, and economical considerations. Treatment options include therapeutic abstinence, bed rest and oxygen supplementation, manual aspiration, chest tube drainage, and immediate thoracoscopic or even open surgical intervention (1, 6).
In a recent expert-based consensus recommendation report (7), there was good to very good consensus on the following treatment recommendations in first episodes of primary spontaneous pneumothorax: simple observation in the case of clinically stable patients with small pneumothoraces; lung reexpansion with a small-bore catheter or placement of a chest tube attached to either a Heimlich valve or a water seal device in the case of clinically stable patients with large pneumothoraces; and lung reexpansion with a chest drain or small bore catheter attached to a water-seal device or applying suction of unstable patients with large pneumothoraces (7). Nevertheless, because of its minimal morbidity, outpatient-based implementation, purported equal efficacy as compared with chest tube drainage, and low cost, manual aspiration followed by immediate discharge and follow-up has been recommended by some authors as the treatment of choice in uncomplicated primary spontaneous pneumothorax (8–11).
However, in every study published so far on manual aspiration for pneumothorax, mixed patient populations (first episode and recurrent episodes, primary and secondary pneumothorax, spontaneous and iatrogenic pneumothorax) were studied, and only two randomized, prospective, comparative studies albeit in mixed patient groups are available. This is the first randomized, prospective, multicenter pilot study comparing manual aspiration to chest tube drainage in a homogenous group of patients with a first episode of primary spontaneous pneumothorax.
Patients with a documented first episode of primary spontaneous pneumothorax were considered eligible for inclusion (1) if they were symptomatic (chest pain, dyspnea), regardless the size of the pneumothorax or (2) if the pneumothorax size was greater than 20% as estimated by Light's formula (estimated percent of pneumothorax = (1 − L3/H3) × 100, where H = diameter of the hemithorax, and L = diameter of the “collapsed” lung) (12). Exclusion criteria were the presence of underlying lung disease, a history of previous pneumothorax, and tension pneumothorax. After oral informed consent, and after confirmation of absence of exclusion criteria, 60 consecutive patients presenting in five hospitals (one tertiary care academic hospital in Brussels, and four regional general hospitals in Flanders) were included. Patients were randomized at each center with separate random number lists into one of the two treatment groups using a computer-generated table numerically corresponding with the treatment group.
The protocol was approved by the Ethical Committees of the participating centers.
Manual aspiration was performed as follows: patients were seated in semi-supine position. After skin disinfection and field preparation, a small-caliber polyethane intravenous needle catheter (Intracath, 16 Ga; Becton Dickinson, Sandy UT) was introduced after local anesthesia with 2% lidocaine in the second or third intercostal space, at the midclavicular line. After the needle had entered the pleural space (which was witnessed by bubbling of air in the lidocaine-filled syringe), the needle was directed apically and the catheter was advanced into the pleural space for 5–10 cm. While holding the catheter in place, the needle was then withdrawn. The catheter was fixed to the skin using sterile adhesive tape and connected via a three-way valve to a 50-ml syringe. Air was manually aspirated, until a resistance was felt and air was no longer aspirated. Thereafter, a chest X-ray was performed with the catheter in place, or the catheter was immediately withdrawn and a chest X-ray was performed afterwards, depending on local logistical capacity: in two centers, aspiration catheters were removed after the first attempt of manual aspiration because of the relative difficulties in local patient transportation to and from the radiology department. If lung expansion was complete, or when only a very small rim of apical air was present, the patient was discharged. If no lung expansion was obtained, a second aspiration attempt through the original aspiration catheter when left in place or through a newly inserted catheter at the same skin site (in case of removal of the original catheter for patient transportation) was performed or subsequent treatment was proposed at the discretion of the local pulmonologist. If a second attempt was successful, the patient was discharged. If, during manual aspiration, 4,000 ml and greater had to be aspirated without signs of reexpansion, or if a second manual aspiration attempt was unsuccessful, chest tube drainage was performed. After discharge, a control chest X-ray was ordered within 48 hours and at 1 week. Thereafter, chest X-rays were ordered at 2, 6, and 12 months or when indicated. Chest tube drainage was performed with 16 F or 20 F plastic (Argyle; Sherwood Medical, Tullamore, Ireland) tubes. The chest tube was inserted under local anesthesia, at the anterior midclavicular second interspace, or at the fourth or fifth interspace, at the midaxillar line, and directed to the apex. The drain was connected to a four-chamber system at water seal (0 cm H2O) or slight aspiration (−5 cm H2O). When air bubbling had stopped and a chest X-ray had confirmed complete lung expansion, the drain was left at water seal for 24 hours. After a control chest X-ray, the drain was then removed at expiration, and the patient was allowed to leave the hospital. Chest drainage was prolonged as long as air leakage persisted and/or no complete lung expansion was obtained for a maximum of 7 days. Thereafter, subsequent treatment (e.g., thoracoscopy, thoracotomy) was left at the discretion of the attending pulmonologist. After discharge, patients were seen at 1 week, 2 months, 6 months, and 12 months, or earlier when indicated.
Primary endpoints were immediate success rates, 1-week success rates, and 1-year success rates for both treatment groups.
Immediate success for manual aspiration was defined as complete or nearly complete and persistent lung expansion immediately following manual aspiration. Immediate success for chest tube drainage was defined as complete lung expansion, absence of air leakage, and chest drain removal within 72 hours after tube placement.
One-week success rates were defined on an intention-to-treat basis in both groups. In the manual aspiration group, subsequent chest tube drainage was proposed in case of immediate failure: 1-week success of manual aspiration on an intention-to-treat basis was therefore defined as complete and persistent lung expansion at 7 days after the first attempt of aspiration (followed by chest tube drainage in case of unsuccessful aspiration). In the chest tube drainage group, 1-week success was defined as complete lung expansion followed by chest tube removal within 7 days after the first tube insertion.
One-year success in both groups was defined as the absence of recurrent pneumothorax during a 1-year follow-up period.
Secondary endpoints were safety, hospitalization (percent of patients), and duration of hospitalization. Discharge criteria were as follows. After successful manual aspiration, patients were offered immediate discharge from the hospital. Chest tubes were removed, without clamping, if there was complete lung expansion and absence of bubbling for at least 24 hours at water seal. Patients were discharged at the same day of drain removal. After thoracoscopic talc poudrage, a chest tube was left in place for at least 24 hours and then removed as described previously; the patients were discharged at the day of drain removal. After thoracotomy, the patients were discharged at the surgeon's discretion.
Demographic and descriptive data are given in means ± 1 SD and compared using a two-tailed Student t test. Categorical variables are compared using chi-square or Fisher exact test, when appropriate. Power analysis was performed considering α = 0.05 and 1 − β = 0.8. Statistical significance was accepted at a p value less than 0.05.
Patient characteristics for each group are listed in Table 1
Chest Tube Drainage
|Sex, M/F||20/7||28/5||p = 0.4|
|Age, range, years||28.2 ± 11.6 (16–52)||28.9 ± 8.9 (18–50)||p = 0.8|
|% Total PTX||20/27 (74%)||25/33 (76%)||p = 0.9|
|Right/left (%) sided PTX||61/39||64/36||p = 0.8|
|BMI, range||20.9 ± 3.2 (15.9–27.4)||21 ± 2.5 (16–25.4)||p = 0.9|
|Light index, %||62.1 ± 26.9||63.6 ± 24.7||p = 0.8|
|Smoking status||16/27||27/33||p = 0.1|
|(10 current, 6 ex)||(25 current, 2 ex)|
Study endpoint analyses are given in Table 2
MA (n = 27)
CTD (n = 33)
|Immediate success||16/27 (59.2%)||21/33 (63.6%)||p = 0.90|
|1-week success rates||25/27 (93%)*||28/33 (85%)||p = 0.40|
|Hospitalization||14/27 (52%)†||33/33 (100%)||p < 0.0001|
|Hospital stay, days||3.4 ± 1.6||4.5 ± 2.7||p = 0.20|
|1 Year recurrence rate||7/27 (26%)||9/33 (27%)||p = 0.90|
|Time of recurrence, weeks||13.4 ± 10.2||9 ± 8.47||p = 0.36|
|Urgent readmissions after discharge||0||0|
Taking into consideration the statistical limitations of our study, immediate success rates seemed similar in both groups: 16 out of 27 or 59.2% of manual aspiration patients versus 21 out of 33 or 63.6% of chest tube drainage patients.
Of the 11 patients in whom manual aspiration was unsuccessful at first attempt, a second attempt was made in six, but was also without success. In nine patients, chest tube drainage was eventually performed, which was successful within 1 week in every case. In two patients, immediate thoracoscopy with talc poudrage for pleurodesis was performed on explicit patient request. Hence, in the intention-to-treat manual aspiration group, there was a 25 out of 27 or 93% success rate of manual aspiration followed by chest drainage within 1 week.
In the chest tube drainage group, treatment was successful within 72 hours in 21 out of 33 or 63.6% of patients. In seven of the remaining 12 patients, prolonged chest drainage was successful within 1 week, whereas in five patients thoracoscopy or thoracotomy was indicated because of persistent air leaks for more than 7 days (7). Hence, 1-week success rate in the chest tube drainage group was 28 out of 33 or 85%.
In the manual aspiration group, 14 out of 27 (52%) of patients were hospitalized, with a mean stay of 3.41 ± 1.56 days (range 1–6 days). They included the nine patients in whom eventual chest drainage was necessary, three patients in whom manual aspiration was immediately successful but who preferred to stay overnight because of fear for recurrence, and two patients who requested immediate pleurodesis by means of thoracic talc poudrage after failure of manual aspiration. Two patients had a prolonged hospital stay because of social reasons: both had received a chest tube after initial failure of manual aspiration, which was removed on Day 4 and Day 5, respectively. Their hospitalization was prolonged to 14 days however because of social reasons, and they were therefore excluded from the mean hospitalization stay calculation. Hospitalization was of course 100% in the chest tube drainage group (p < 0.0001), with a mean stay of 4.5 ± 2.7 days (range 1–10 days).
Recurrence rates at 1-year follow-up were 7 out of 27 (26%) in the manual aspiration group and 9 out of 33 (27.3%) in the chest tube drainage group (p = 0.86). Recurrences were treated with thoracoscopic talc poudrage (n = 12), axillar thoracotomy (n = 2) and drainage (n = 2). Mean time to a first recurrence was 13.4 ± 10.2 weeks in the manual aspiration group, versus 9 ± 8.5 weeks in the chest tube drainage group (p = 0.4). None of the patients who returned home after the manual aspiration procedure had to be readmitted because of complications or early recurrence of symptoms. The earliest recurrence occurred 3 weeks after discharge.
This is the first prospective, randomized, multicenter study comparing manual aspiration and chest tube drainage as first treatment in a homogenous population of patients presenting with a first episode of primary spontaneous pneumothorax. In this pilot study, manual aspiration and chest tube drainage have similar immediate and long-term (1 year) success rates.
Primary spontaneous pneumothorax is a common pathology in daily pulmonary practice and accounts for a significant health-care expenditure (7, 13). Surprisingly, generally accepted and methodologically sound guidelines for the treatment of primary spontaneous pneumothorax do not exist, explaining the extensive practice variation in management (7, 14).
There seems to be a general consensus on a conservative approach in patients with first episodes of primary spontaneous pneumothorax who are asymptomatic and have small (< 20% as estimated by Light's formula, or a small rim of air/distance of cupula to lung apex < 3 cm) pneumothoraces: in these cases, simple observation with or without oxygen supplementation is recommended (5, 7, 8). In patients requiring active treatment (i.e., symptomatic patients and/or large pneumothoraces), treatment options and recommendations vary (7); the reason for this variation relates to the differences in treatment goals (simple removal of air versus prevention of recurrences), and to the lack of prospective, comparative studies addressing various treatment options in homogenous patient populations.
Whether to treat all patients presenting with a first episode of primary spontaneous pneumothorax immediately with some form of pleurodesis treatment, or to wait for a first recurrence of pneumothorax, should be decided after analysis of the risk of recurrence (which averages 30% after a first episode ) and the direct and indirect costs of the procedure (9, 15). Although in one study (15) Video-assisted Thoracic Surgery (VATS) treatment is suggested to be more cost effective than chest tube drainage, even in first episodes, it remains a fact that 73% of patients had unnecessary operations. Hence, pending other cost-effectiveness studies, there is quite good consensus that procedures to prevent recurrence should be reserved for the second pneumothorax occurrence (7, 9).
If one agrees, therefore, that treatment of a first episode of primary spontaneous pneumothorax should consist of simple air removal and not prevention of recurrences, options are simple manual aspiration with immediate catheter removal or placement of a small-bore catheter (⩽ 14 F) or a small to medium-sized (16–22 F) chest tube attached to a Heimlich valve or to a water-seal device. Although manual aspiration is recommended by some (8–11), mainly because of its simplicity, lack of invasiveness, outpatient character, and low cost (32, 35), chest tube drainage is by far the most popular and recommended air evacuation technique (14, 16). Disadvantages of manual aspiration are reported to be the following: (1) the absence of recurrence prevention; (2) the heterogenous and hence, difficult to interpret literature (e.g., mixed primary and srinisecondary pneumothorax); and (3) the unknown safety of sending a patient home with an aspirated pneumothorax (17). The first disadvantage reported is, in our opinion, irrelevant because neither manual aspiration nor chest tube drainage has any recurrence prevention effect (17–19). The two other reported disadvantages are the subject of this study.
The literature on manual aspiration in spontaneous pneumothorax includes 17 papers on more than 800 patients, none of which, however, report on a homogenous population of first episodes of primary spontaneous pneumothorax (11, 20–36). The immediate success of manual aspiration, all patients confounded, ranges from 38 to 86%, averaging 72% (391 of 544 patients). Late recurrences (at least 1-year follow-up) after manual aspiration are reported in only six studies (11, 20–22, 28, 29) and vary between 0 and 30%. Complications are only rarely reported (one haemothorax, two retained catheter tips, six subcutaneous emphysema, and two vasovagal reactions) and seem to occur in about 1% of aspirations. There are two prospective, comparative studies on manual aspiration versus chest tube drainage in spontaneous pneumothorax (11, 20). In the British Thoracic Society Research Committee study (11), manual aspiration and chest tube drainage were reported to be equally successful in first and recurrent episodes of spontaneous (presumably primary) pneumothorax, with manual aspiration being less painful, leading to less admission rates, to a reduction in the need for pleurectomy, and without increase in recurrence rate at one year. In the Andrivet study (20), delayed (72 hours) needle aspiration was less effective than immediate chest tube drainage (67 versus 93%) in the first part of their study. In the second part, immediate needle aspiration was successful in 68.5% of patients. Recurrence rates at 3 months in the various treatment arms did not differ significantly (14, 29, and 30%). In our study, immediate manual aspiration had a comparable success rate of 59.2%; immediate chest tube drainage success in our study, however, was defined as complete success and discharge within 72 hours (based on Schoenberger's findings of an 82% air leak stop within 48 hours after spontaneous pneumothorax and 100% in leak stop within 72 hours after iatrogenous pneumothorax) (18, 36), whereas in Andrivet's study chest tube drainage success was assessed up to 10 days after tube placement. Our observation of an 85% 1-week success rate of chest tube drainage, therefore, is completely comparable with Andrivet's data.
We observed no side effects, complications, or need for urgent readmissions in the manual aspiration treated group, confirming the excellent safety record in the literature. Major advantages of manual aspiration over chest tube drainage are its lack of significant morbidity and the reduced need for hospitalization. Of the 16 patients in whom manual aspiration was immediately successful, 13 were discharged. The three remaining patients also were allowed to leave the hospital but preferred to stay overnight because of fear for recurrence. They were discharged the following day without problems. The 11 patients in whom manual aspiration was unsuccessful, were hospitalized for chest tube drainage (n = 9) or for thoracoscopic talc poudrage (n = 2). This contrasts with the 100% hospitalization rate in the chest tube drainage group. Although no actual costs were calculated, these findings may suggest a superior cost effectiveness for manual aspiration as first line treatment in first episodes of primary spontaneous pneumothorax.
Another interesting observation was that if after a first attempt of manual aspiration complete lung expansion could not be obtained, a second attempt was also unsuccessful. This is most probably due to the presence of a persistent air leak, and this suggests that a single manual aspiration attempt may be sufficient before turning to another treatment.
In conclusion, this first prospective, multicenter, randomized pilot study in a homogenous population of patients presenting with first episodes of primary spontaneous pneumothorax, suggests that manual aspiration and chest tube drainage may be equally effective in terms of immediate and long-term success. Morbidity of manual aspiration is very low and the procedure is very well tolerated. Furthermore, manual aspiration is proven safe, and can be performed in the majority of patients as an outpatient procedure, which may reduce costs substantially. Pending larger scale studies, these data suggest that manual aspiration may be the preferable first line treatment in first episodes of primary spontaneous pneumothorax and that guidelines may have to be revised accordingly in the future.
The authors thank Lieve Van Gijseghem for her secretarial assistance, all referring and assisting colleagues, and the “Forum Vlaamse Longartsen” for logistical support.
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