Article Text
PDF
Abstract
Objective Small-bore pigtail catheters have been found to be effective in the treatment of primary spontaneous pneumothorax (PSP) in adults. The aim of this study was to compare the effectiveness of small-bore pigtail and large-bore catheters in the treatment of PSP in young adolescents.
Materials and methods Young adolescents (<18 years) with initial PSP were treated with aspiration (control group), small-bore pigtail catheters or large-bore catheters. Treatment was determined on a case-by-case basis with parental consultation. Success rate, recurrence rate (within 12 months), duration of hospital stay, duration of catheter insertion, and complications were analysed.
Main results There were 41 patients treated: aspiration, n=8; small-bore pigtail catheters, n=10; large-bore catheters, n=23. Demographic and baseline clinical characteristics were similar between groups. The success rates were 50.0% and 65.2% in the small-bore pigtail and large-bore catheter groups, respectively. Corresponding recurrence rates were 20.0% and 56.5%. There was no difference between the small-bore pigtail and large-bore catheter groups in the duration of hospital stay in patients for whom treatment was successful; however, the duration of catheter insertion was significantly shorter in the small-bore pigtail catheter group compared with the large-bore catheter group in patients for whom treatment was successful (p<0.05). There were no major complications in either catheter treatment group and few minor complications (small-bore pigtail catheter, n=2; large-bore catheter, n=4).
Conclusions The findings suggest that small-bore pigtail catheters may be as effective as large-bore catheters for the initial treatment of PSP in young adolescents.
- Primary spontaneous pneumothorax
- small-bore pigtail catheters
- large-bore catheters
- adolescents
- effectiveness
- pneumothorax
Statistics from Altmetric.com
- Primary spontaneous pneumothorax
- small-bore pigtail catheters
- large-bore catheters
- adolescents
- effectiveness
- pneumothorax
Introduction
Primary spontaneous pneumothorax (PSP) is defined as the accumulation of air in the pleural space in the absence of clinical signs of underlying lung disease. It is relatively uncommon in adults, and even more so in paediatric populations.1 Indeed, the true incidence of paediatric PSP is unknown.1 There is evidence to suggest, however, that paediatric PSP, like adult PSP, is more common in male than female patients.1 As paediatric patients who experience PSP may have a higher risk of recurrence than adults,1 ,2 determining and implementing the most appropriate means of treatment is particularly important.
There are no guidelines currently available for the treatment of paediatric PSP. Initial treatment options include conservative management, aspiration, and insertion of intercostal chest catheters/tubes. Of the invasive treatment options, simple aspiration and large-bore chest catheter insertion have been favoured for many years.3–5 Simple aspiration is technically straightforward, but is limited by a high rate of failure (up to almost 50%).6–8 Insertion of large-bore chest catheters can be effective, but is limited by a higher risk of complications and increased post-procedural pain.9 In an effort to reduce the complications and pain associated with the placement of large-bore chest catheters, small-bore pigtail catheters have been used and found to be effective in the treatment of adult PSP.3 ,10–12 The insertion of pigtail catheters is thought to be less traumatic than insertion of large-bore catheters.11 Only one study to date, however, has directly compared the efficacy of small-bore pigtail and large-bore catheters in the treatment of paediatric pneumothoraces: Dull and Fleisher found that small-bore pigtail catheters were a safe and effective alternative to large-bore catheters in the treatment of paediatric pneumothoraces of various causes, including spontaneous.13
The aim of our retrospective study was to compare the effectiveness of small-bore pigtail and large-bore catheters in the treatment of paediatric PSP, specifically in a cohort of young adolescents.
Materials and methods
This was a retrospective study involving young adolescents with PSP who were treated in the paediatric intensive care unit of Kaohsiung Chang Gung Memorial Hospital from April 2000 to October 2010. The diagnosis of PSP was made with reference to clinical symptoms and chest x-ray examinations. All patients were less than 18 years of age and had PSP for the first time. Patients with pneumothorax because of trauma, necrotising pneumonia or iatrogenic and other pre-existing lung disease were excluded from the study. The study complies with the Declaration of Helsinki and was approved by the institutional review board of Chang Gung Memorial Hospital-Kaohsiung Medical Center (Taiwan). Owing to the retrospective nature of this study, written consent was waived.
Treatment
Patients with mild PSP (local, small size) were treated with observation or aspiration. Patients with moderate or severe PSP were treated with aspiration, small-bore pigtail catheters or large-bore catheters. The choice of treatment was determined by the attending physician on a case-by-case basis with parental consultation. Note: patients who had received an initial aspiration treatment were not included in this study.
Small-bore pigtail catheters (8–12 Fr: SKATER Drainage System; PBN Medicals, Stenlose, Denmark) were inserted under local anaesthesia via the superior part of the 4th to 6th intercostal space at the middle axillary line using a modified Seldinger technique. After insertion, the catheter was connected to a Heimlich one-way-valve drainage bag.
Large-bore catheters were inserted under local anaesthesia via the 4th or 5th interspace, at the midaxillary line, and directed to the apex according to the standard procedure. After insertion, the catheter was connected to a chest drainage unit with a water seal. Low level suction was only applied if there was no re-expansion after 48 h or if there was a continuous air leak. Catheter position was confirmed by chest radiography.
Measures and assessments
Demographic and baseline clinical characteristics were recorded, including signs and symptoms and side and size of pneumothorax. Chest radiographs were examined to estimate pneumothorax size using the Light index,14 that is, Y=(A3−B3)/A3, where Y is the ratio of the cube of the hemithorax diameter (A) to the collapsed lung diameter (B). A large pneumothorax was defined as one that was ≥2 cm or that had a ratio ≥50%.4 The following treatment-related variables were recorded: success rate, days of catheter insertion, days of hospital stay, complications and PSP recurrence rate. Recurrence of PSP was defined as recurrence within 12 months. Treatment success was defined by complete or near-complete lung expansion after insertion without the need for a large-bore chest tube or surgical treatment. Treatment failure was defined by the need for a large-bore chest tube or surgical treatment for ineffective drainage.
Major complications of treatment were haemothorax, perforation of the intra-abdominal wall or intrathoracic organs, and diaphragmatic laceration. Minor complications of treatment were kinking of the catheter, subcutaneous emphysema, skin infection, and the need to reposition or change the catheter.
Statistical analysis
Continuous variables are presented as median (25th, 75th centile) and were compared between groups using the Kruskal–Wallis method. Categorical variables are presented as count (%) and were compared between groups using Fisher's exact test. Logistic regression was performed to assess the main effect of success and recurrence rates, with adjustment for significant baseline characteristics. The duration of hospital stay was compared between groups using the Kruskal–Wallis method, with type I error adjustment for multiple comparisons. The duration of catheter insertion was compared between groups by Wilcoxon rank sum test. All statistical assessments were evaluated at the 0.05 level of significance. Statistical analyses were performed using SAS V.9.2 software.
Results
A total of 41 patients with PSP were included in the study. Of these 41 patients, eight were treated with needle aspiration, 10 were treated with small-bore pigtail catheters, and 23 were treated with large-bore catheters. The demographic and baseline clinical characteristics of patients in the treatment groups were similar (table 1).
Baseline demographic and clinical characteristics of young adolescents with primary spontaneous pneumothorax who received treatment with needle aspiration, small-bore pigtail catheters, or large-bore catheters
Practically, only pneumothorax of small size will be treated by aspiration, so the pneumothorax size of the aspiration group was smaller than those of the other two groups. There were seven female patients with a median (25th, 75th centile) age of 15 years (13, 15), and 34 male patients with a median age of 16 years (15, 16). There were 25 (61.0%) patients with left-side pneumothorax, and 16 (39.0%) patients with right-side pneumothorax. The most common clinical symptom was chest pain (n=37, 90.2%), followed by dyspnoea (n=14, 34.2%) and cough (n=9, 22.0%). The median (25th, 75th centile) pneumothorax size was 56.9% (47.2, 75.6).
The treatment success rates were 75% (6/8 patients) for the needle aspiration group, 50.0% (5/10 patients) for the small-bore pigtail catheter group, and 65.2% (15/23 patients) for the large-bore catheter group. Corresponding PSP recurrence rates were 25.0% (2/8 patients), 20.0% (2/10 patients) and 56.5% (13/23 patients) for the needle inspiration, small-bore pigtail and large-bore catheter groups, respectively. There were no significant between-group differences in success or recurrence rates (table 2).
Comparison of success and recurrence rates in young adolescents with primary spontaneous pneumothorax who received treatment with needle aspiration, small-bore pigtail catheters or large-bore catheters
Among the patients who were successfully treated, the length of hospital stay was longer in the needle aspiration group than in the large-bore catheter group (7 vs 5 days, p=0.006, figure 1A). Catheters remained inserted for significantly fewer days in the small-bore pigtail catheter group than in the large-bore catheter group (3 vs 5 days, p=0.037, figure 1B).
Comparisons of the duration of hospital stay (A) and duration of catheter insertion (B) for young adolescents with primary spontaneous pneumothorax who were successfully treated with needle aspiration (n=6/8 patients; duration of hospital stay only) or small-bore pigtail (n=5/10 patients) or large-bore (n=15/23 patients) catheters. Data are presented as median (25th, 75th centile) and were compared by the Kruskal–Wallis method (duration of hospital stay) or Wilcoxon rank sum test (duration of catheter insertion). *Significant between-group difference (p<0.05).
There were no major complications in either of the catheter treatment groups, but six (18.2%) patients experienced minor complications. The minor complications included catheter kinking (n=1) and the requirement for catheter repositioning (n=1) in the small-bore pigtail catheter group, and skin infection (n=1), catheter kinking (n=1), and the requirement for catheter repositioning (n=2) in the large-bore catheter group.
Discussion
In this retrospective study involving 41 patients, we examined the effectiveness of small-bore pigtail catheters for the initial treatment of paediatric PSP. No previous study has directly examined the effectiveness of small-bore pigtail catheters in young adolescents with PSP alone. We found that small-bore pigtail catheters were as effective as large-bore catheters, as indicated by similar success and recurrence rates. Further, we found that the duration of hospital stay was similar between the small-bore pigtail and large-bore catheter groups, whereas the duration of catheter insertion was significantly shorter in the small-bore pigtail catheter group. These findings suggest that small-bore pigtail catheters may be as effective as large-bore catheters for the initial treatment of PSP in young adolescents.
We found that there was no difference in the treatment success rate between paediatric patients who received small-bore pigtail catheters (50.0%) and those who received large-bore catheters (65.5%). This finding, and the associated success rates, are consistent with those reported by Dull and Fleisher, who found success rates of 54.0% and 56.0% in paediatric patients who received small-bore pigtail and large-bore catheters, respectively, for pneumothoraces of mixed aetiology.13 The lack of a significant between-group difference in the treatment success rate is also consistent with the findings from several studies comparing success rates after treatment with small-bore pigtail and large-bore catheters in adults with spontaneous pneumothorax.10 ,11 In keeping with the success rate findings, we also found that there was no between-group difference in the rate of PSP recurrence. Taken together, these findings suggest that small-bore pigtail catheters are as effective as large-bore catheters for the treatment of paediatric PSP.
In a previous study involving paediatric intensive care unit patients, Roberts and colleagues found that heavier children (>10 kg) had a significantly higher failure rate than lighter children (<10 kg) after small-bore pigtail catheter insertion for drainage of pleural effusion or pneumothorax (not PSP).15 The authors suggested that this interesting finding may have been due to an increased likelihood of catheter compression in heavier children with thicker chest walls. Unfortunately, we did not have a sufficient number of patients in our study to assess the impact of body weight on treatment success with insertion of small-bore pigtail catheters for treatment of PSP. The possibility that body weight may affect the rate of success when pigtail catheters are used in the treatment of PSP warrants further investigation.
Interestingly, we found that small-bore pigtail catheters remained inserted for significantly fewer days than large-bore catheters, suggesting that small-bore pigtail catheters may have improved air drainage and more rapid lung expansion than large-bore catheters. Previous studies involving paediatric populations13 and adults10 have reported insignificant trends for decreased duration of insertion for small-bore pigtail catheters compared with large-bore catheters. In contrast with the between-group difference in the duration of catheter insertion, there was no significant difference in the duration of hospital stay between the small-bore pigtail and large-bore catheter groups. There was, however, a numeric difference in the duration of hospital stay, which is consistent with previous reports.10 ,13 The lack of a corresponding significant difference in the duration of hospital stay in our study may be explained by the fact that staff were less experienced in the use of small-bore pigtail catheters (compared with large-bore catheters), and hence may have been overly conservative in discharging patients after catheter removal.
There were no major complications in our cohort and a relatively low (18.2%) incidence of minor complications. The incidence of minor complications in both groups was too low to allow any definitive conclusions to be made; however, our findings suggest that small-bore pigtail catheters may be as safe as large-bore catheters for the treatment of paediatric PSP.
The use of small-bore pigtail catheters in the treatment of PSP offers several potential advantages over the use of large-bore catheters. First, the insertion procedure is more straightforward for small-bore pigtail catheters than for large-bore catheters. Neither an incision nor dissection of the chest wall is required for small-bore pigtail catheter insertion; hence, the extent of procedural trauma is reduced compared with large-bore catheter insertion. Indeed, there is evidence that small-bore pigtail catheters may be associated with less pain than large-bore catheters.9 Further, Dull and Fleisher reported that paediatric patients with pneumothorax who were treated with small-bore pigtail catheters used less pain medication than those who were treated with large-bore catheters.13 Second, small-bore pigtail catheters are more comfortable and less restrictive in terms of ambulation than large bore catheters. Finally, small-bore pigtail catheters are clearly more cosmetically appealing than large-bore catheters.
Our study has a number of limitations that warrant acknowledgement. First, only a small number of patients were included in the study, thus limiting the power of statistical analyses. It should be noted, however, that cases of paediatric PSP are quite rare; hence, obtaining a large and relatively homogeneous patient population for studies such as ours is challenging and would require a multicentre study. Second, our study has a number of inherent limitations associated with the retrospective nature, including incomplete availability of medical records.
In conclusion, our findings suggest that small-bore pigtail catheter insertion may be as effective and safe as large-bore catheter insertion for the initial treatment of PSP. We believe that small-bore catheter insertion should be considered as the treatment of choice for the first (but not recurrent) episode of large PSP in young adolescents. A larger scale, prospective trial is needed to more comprehensively assess the efficacy and safety of small-bore pigtail catheters in the treatment of paediatric PSP.
References
Footnotes
-
Competing interests None.
-
Ethics approval Institutional Review Board of Chang Gung Memorial Hospital-Kaohsiung Medical Center.
-
Provenance and peer review Not commissioned; externally peer reviewed.