Thoracic, abdominal, and pelvic fluid collections are commonly encountered clinical entities. Image-guided percutaneous continuous catheter drainage is an interventional radiology procedure that is now considered to be the standard curative therapy for thoracic, abdominal, and pelvic fluid collection or abscesses. ¹ Percutaneous catheter drainage (PCD) has over time replaced open surgical drainage (OSD) in all but the most complicated or inaccessible cases. ² Most of the fluid collections permit easy accessibility. However, deep-seated collections or collections in close proximity to adjacent structures could prove to be inaccessible and call for procedural modifications and/or alternate approaches. The feasibility of the drainage is dependent on the consistency of the collection. ³ Thus, PCD is a multifactorial procedure that is based on the size, location, character, and configuration of the fluid collection. ⁴

PCD bridges the gap between non-invasive and surgical intervention with minimally invasive, image-guided drainage by utilizing ultrasound (US) or computerized tomography (CT). ^{5 , 6} PCD using US guidance is the preferred procedure when the fluid collection is large and is localized superficially. In contrast, deeper collections are better evaluated under CT guidance. However, the major advantages of using US over CT are attributed to the lack of radiation, lower cost, flexibility, portability, and shorter period. Pigtail catheters with a single lumen and multiple side holes are generally the preferred catheters in the continuous drainage method of these collections. ⁷

This study aims to evaluate the efficacy, feasibility, safety, and relevant clinical outcomes of image-guided percutaneous (pigtail) catheter drainage of thoracic, abdominal, and pelvic fluid collections. It also aims to assess the causes of complications and the failure of PCD.

Several studies have evaluated and proved the efficacy and feasibility of image-guided drainage of thoracic, abdominal, and pelvic fluid collections of varying aetiologies. ^{1 – 5 , 7 – 9} These studies differ in their recommendations for the technique needed to effectively manage fluid accumulations/abscesses, namely INA versus PCD (either in terms of short-term or long-term efficacy with respect to the site of the fluid collections). This study reports, to our knowledge, on the variety of fluid collections with respect to different locations in the body (abdominal, thoracic, and pelvic) and the effectiveness, feasibility, and safety of image-guided PCD in the management of fluid collections in the abdomen, thorax, and pelvis.

Demography - In our study, the majority of the study subjects ( n=83) were aged between 30 to 50 (25.3%), were males (68.9%), and had intra-abdominal collections (61.5%), followed by thoracic (31.3%), and pelvic (7.2%) collections. These characteristics of our study were similar to the ones reported by Abusedera et al, ¹ wherein, they observed that among 84 study subjects (45 males and 39 females), males were 45.1±16.9 years old, while females were 45.5±13.9 years old. Similarly, Raj et al, ¹⁰ in their study of subjects with intra-abdominal collections, reported that the majority of their subjects were aged less than 60 (74.2%), 90.3% were males and 9.7% were females. Therefore, from previous literature and our current study, it is evident that the most common demography presenting with abdominal, thoracic, or pelvic collections is that of middle-aged subjects with a male preponderance.

INA vs PCD – Numerous authors have investigated the effectiveness of either aspiration or PCD in managing fluid collections. ^{1 , 4 , 5 , 11 , 12} Such studies have found that INA alone can be utilized in cases where the abscesses are smaller than 4 cm. ⁵ PCD and antibiotics are the therapy of choice for most abdominal and pelvic abscesses. ^{1 , 13 , 14} Abusedera et al. ¹ and Aziz F et al. ⁴ observed that catheter drainage is the most effective technique for the management of intra-abdominal and pelvic fluid collections. Whereas, according to Wroblicka and Kuligowska, ¹⁵ INA and lavage should be the first line of treatment for multiloculated abscesses in the abdomen and/or pelvis. In this study, the clinical radiologist performing the procedure decided in consultation with the referring clinician whether INA and PCD should be performed in the same sitting or after an interval gap of 48 hours. This study found that when done as an initial step in the management of fluid collections, INA allows for easy and free drainage of the fluid, while guiding an access pathway for catheter placement and collection of uncontaminated samples for further diagnostic evaluation in the laboratory. However, in cases of fluid collections with echogenic contents or high-fluid density, thick-walled collections, deep-seated collections, or abscesses that required immediate evacuation, a pigtail catheter was introduced in the same sitting, and PCD was done. In cases where the residual collection was present after unsuccessful attempts at repeated INA, a catheter was introduced after an interval gap of 48-78 hours (on day 3), after sonographic evaluation of the residual collection.

Size of catheters – Raj et al. ¹⁰ in their study observed that CT was used in 51.6% of cases and USG was used in 49.4% of the cases as modes of image-guidance, and the most commonly used size of the catheter was 10F (54.8%), followed by 12F (35.5%), 14F (6.5%), finally 8F (3.2%). This is similar to our current study, wherein, 61.4% of the patients were subjected to CT-guided catheterization, 36.1% patients were subjected to US-guided catheterization, and 2.4% patients were subjected to both US and CT imaging. Additionally, our study also included 10F sized catheters as the most frequently used (53.01%), followed by 12F (42.17%), and 8.5F (4.82%). However, it is worth noting that although the 10F catheter was widely used in drainage of thoracic (88.46%) and pelvic (83.33%) collections, 12F was more frequently used in cases of abdominal collections (60.78%), followed by 10F (31.37%), and 8.5F (7.84%). In our study, the models and sizes of the catheter(s) used were selected according to the operator’s convenience and preference for the characteristics of the fluid collection. According to Aziz et al, ⁴ the thoracostomy tube is a key therapeutic technique in draining pleural fluid collections, however, because of the force required to breach the chest wall (insertion of chest tube by blunt dissection or by use of a trocar), there is a risk of morbidity. Gammie et al. ¹⁶ succeeded in developing a flexible polyurethane pigtail catheter that can be used at the bedside to drain small pleural effusions. They found that such pigtail catheterization was a less traumatic alternative to traditional catheterization techniques. Furthermore, this is accomplished with catheters with a relatively small-bore. ^{17 – 19} The procedure is less traumatic for the patient than inserting a large tube, and the catheters are pliable enough to be comfortable once in place as long as they are irrigated regularly. In a retrospective analysis of 88 patients conducted by Tsai et al., ²⁰ 27 patients developed pneumothorax following pigtail catheter insertion and resolution was seen in 22 of them. In our study, post-catheterization pneumothorax was reported in two patients with 12F sized pigtail catheters. However, the observed pneumothoraxes were small, apical, and spontaneously resolving. Those subjects with 10F pigtail catheter had no reported pneumothorax. Thus, 10F is considered suitable for drainage of thoracic collections.

Group categorization and outcome of patients – In our study, 38.55% of the patients were categorized into group A (INA + PCD in the same setting), 57.83% of the patients were categorized into group B (INA followed by PCD after an interval gap of 48-72 hours), and 3.61% patients were categorized into group C (INA + PCD + OSD). Groups A and B were compared for the amount of residual collection after PCD. There was no significant difference in the categorized group distribution among outcomes. The PCD of fluid collection in the thorax, abdomen, or pelvis with immediate or delayed INA showed similar results in terms of outcome, suggesting that INA could postpone the PCD in patients with fluid collections. Only three patients (3.6% of 83 subjects) in our study were categorized into group C (patients subjected to OSD because the INA and PCD failed to evacuate the fluid cavity).

In one of the cases presenting with an enterocutaneous fistula of ileum secondary to Crohn’s disease, pigtail catheterization complemented the surgery by aiding the evacuation of the abscess, followed by resection and anastomosis of the involved bowel loops. Abscesses needed immediate intervention, which was carried out by INA followed by PCD in the same sitting.

In a case of acute necrotizing pancreatitis, two pigtail catheters were introduced to drain out the accumulated collections. The procedure involved the use of one pigtail to drain the fluid collected and another catheter to irrigate the cavity with normal saline. The first catheter was introduced through the peritoneal cavity, while the second was introduced through the retroperitoneal cavity. The residual collection was significantly reduced on the follow-up CT imaging. Thus, dual pigtail catheterization for turbid fluid collection and air-containing collections was successful. Figure 7 shows the progression of this patient with acute necrotizing pancreatitis managed with dual pigtail catheterization. It is an alternative to surgical drainage in the treatment of acute necrotizing pancreatitis. ²¹

The two groups – A and B were compared based on the amount of residual collection with a success rate of 93.7% in group A, and 97.9% in group B. The failure rate in both groups was low (6.3% failure rate in group A and 2.1% failure rate in group B). The outcomes of categorized group distribution did not differ significantly. The INA of fluid collection in the thorax, abdomen, and pelvis with immediate or delayed PCD yielded similar findings in terms of outcome, suggesting that INA could defer PCD in patients with fluid collections. Gerzof et al. ²² reported that the use of image-guided PCD to treat liver abscesses has a success rate of 70 to 100%. Similarly, Raj R et al, ¹⁰ reported that PCD had a success rate of 77.4% and a 22.6% failure rate. These higher rates of procedure failure were observed mainly in cases where the patient was either elderly, female, or when a CT scan was used as a guiding technique. Lower success rate with CT-guided drainage could be attributed to the selection bias which favoured CT for deeper-seated and less accessible collections, especially of the pancreas, which is another confounding factor.

To our knowledge, there are no studies that categorized the patients into intervention groups based on the type of procedure and timing of catheterization. Hence, our study provides unique findings in this aspect. Figure 8 depicts a summary of our design and categorization of patients into different intervention groups in the form of a flow chart.

Complications – Major complications such as pneumothorax, liver perforation, or hemothorax are more likely to occur with chest tubes. Unlike chest tubes, pigtail catheters have a low risk of such complications. ³ According to a study by Roberts et al., ¹⁸ 5-6% of patients with pigtail catheter implantations developed significant complications such as hemothorax, pneumothorax, and liver perforation, and 20% had catheter-related complications such as dislodgement, failure to drain, kinking, blockage, and disconnection of the catheter. In the present study, we classified complications as major and minor complications. Major complications (3.6%) included reaccumulation of fluid in the cavity and pneumothorax. Minor complications (68.6%) included pain at the catheter insertion site, hematoma at the insertion site, and catheter-related complications. Pain was the most commonly reported minor complication in our study. Hematomas at the site of insertion were observed in two of the subjects– one patient (1.2%) developed a presacral hematoma, and another patient (1.2%) developed a perinephric hematoma. One patient with empyema in the left hemithorax also developed blockage of the 12F catheter, which was then removed, replaced, and upsized to a 14F catheter at the same site. 22.6% of the patients in our study, however, reported no major or minor complications.

In the present study, both INA and PCD were safe, effective, and minimally invasive techniques to drain abdominal, thoracic, and pelvic fluid collections in the absence of an indication for surgical intervention. INA should be considered an initial step of management for fluid drainage, which acts as a guide for the access pathway for catheter placement for PCD. We conclude that PCD is very effective in draining various types of fluid collections, most commonly serous and purulent fluids. In the majority of cases from our study, image-guided PCD proved to be a time-saving and efficient intervention, making it an intervention of choice in a variety of fluid collections/abscesses.

Open Science Framework: Efficacy, Feasibility, and Safety of Percutaneous Image-Guided Catheter Drainage of Thoracic, Abdominal, and Pelvic Fluid Collections https://doi.org/10.17605/OSF.IO/HPC5G. ²³

This project contains the following underlying data: •

PatientMasterChart.xlsx

Data are available under the terms of the Creative Commons Zero “No rights reserved” data waiver (CC0 1.0 Public domain dedication).