In vitro evaluation of percutaneous drainage catheters: Flow related to connections and liquid characteristics.

PURPOSE: To evaluate the effect of catheter connections on drainage catheters' flow rate. MATERIALS AND METHOD: The in vitro model used commercially available catheters (8.5-F, 10.2-F, 12-F, and 14-F), connections - Luer-lok (2.33mm inner diameter), and stopcocks (1.33mm, 2.00mm, and 2.67mm inner diameters), water, ultrasound gel, textured vegetable protein (TVP) 2-mm particles, and collection bags. Plain water, viscous fluid (30% ultrasound gel solution in water), or water/viscous fluid with TVP were placed in collection bags and drained by gravity through each of the catheters and each connection. The flow rate was measured, recorded, and compared for each catheter and each connection as well as to the control flow rate of the catheters without connections. Ten one-minute trials were performed, and the mean flow rates were analyzed using Student t-test and Pearson correlation coefficient. RESULTS: Flow rate was significantly decreased in the 12-F and 14-F catheters with all stopcock and Luer-Lok connections with both water and viscous fluids. There was no significant reduction in flow for the 8.5-F and 10.2-F catheters with the 2.00-mm, 2.33-mm, and 2.67-mm connections; flow rate was significantly decreased in the 8.5-F and 10.2-F catheters with the 1.33-mm connection. A majority of trials with particulate fluid became occluded, and no consistent pattern between connections could be made. CONCLUSION: This in vitro study suggests that stopcock and Luer-Lok connections limit catheter flow rate when their inner diameter is less than that of the drainage catheter.

Sequential inferior vena cava filter insertion and peripherally inserted central catheter placement through upper extremity veins.

PURPOSE: To report the sequential placement of inferior vena cava filter (IVCF) and peripherally inserted central catheter (PICC) using the same upper extremity venous access. MATERIAL AND METHODS: This is a retrospective study that reviewed the medical records of 379 consecutive patients who underwent IVCF insertion during a 39-month period at our center. Of these 379 patients, 28 patients had sequential insertion of an IVCF and a PICC through the same upper extremity venous access. The same vein entry site was used for placement of the IVCF followed by PICC insertion. Data collected included: indication and duration of IVCF and PICC placement, access site location, complications, and the type of IVCF. RESULTS: IVCFs were placed for prophylactic purposes in 15 patients (53.6%) and therapeutic purposes in 13 patients (46.4%). Right upper extremity veins were used for venous access in 27 patients (96.4%): brachial (n=16), basilic (n=9), and cephalic (n=2). The left basilic vein was used in one patient (3.6%). IVCFs were temporary in 20 patients (71.4%) and permanent in 8 patients (28.6%). There were no procedural complications. The OptEase filter was used in 23 patients (82.1%) and the TrapEase filter was used in 5 patients (17.9%). CONCLUSION: Simultaneous IVCF and PICC insertion using the same upper extremity venous access was feasible and safe in our series. This combined technique provides the patient with central venous access for repeated blood collections and intravenous therapy.

Number and location of drainage catheter side holes: in vitro evaluation.

AIM: To evaluate the influence of number and location of catheter shaft side holes regarding drainage efficiency in an in vitro model. MATERIALS AND METHODS: Three different drainage catheter models were constructed: open-ended model with no side holes (one catheter), unilateral side hole model (six catheters with one to six unilateral side holes), and bilateral side hole model (six catheters with one to six bilateral side holes). Catheters were inserted into a drainage output-measuring device with a constant-pressure reservoir of water. The volume of water evacuated by each of the catheters at 10-second intervals was measured. A total of five trials were performed for each catheter. Data were analysed using one-way analysis of variance. RESULTS: The open-ended catheter had a mean drainage volume comparable to the unilateral model catheters with three, four, and five side holes. Unilateral model catheters had significant drainage volume increases up to three side holes; unilateral model catheters with more than three side holes had no significant improvement in drainage volume. All bilateral model catheters had significantly higher mean drainage volumes than their unilateral counterparts. There was no significant difference between the mean drainage volume with one, two, or three pairs of bilateral side holes. Further, there was no drainage improvement by adding additional bilateral side holes. CONCLUSION: The present in vitro study suggests that beyond a critical side hole number threshold, adding more distal side holes does not improve catheter drainage efficiency. These results may be used to enhance catheter design towards improving their drainage efficiency.

Percutaneous abscess drainage: update.

During the approximately 20 years that percutaneous abscess drainage (PAD) has been an extant procedure and as the millennium begins, PAD has become, by consensus, the treatment of choice for abscesses. Indications for PAD continue to expand, and currently almost all abscesses are considered amenable. On occasion, PAD is an adjunctive procedure that provides a beneficial temporizing effect for the surgeon who eventually must operate for a coexisting problem such as a bowel leak. Simple unilocular abscesses are cured almost uniformly by PAD; more complicated abscesses, such as those with enteric fistulas (e.g., diverticular abscess) or pancreatic abscesses, have cure rates ranging from 65% to 90%. Various catheters and insertion techniques have proven effective. Ultrasonography, computed tomography, and fluoroscopy are the staple modalities that guide PAD. PAD is the prototype interventional radiology procedure, providing detection of the abscess by imaging, needling for diagnosis, and catheterization for therapy.

CT-guided catheter drainage of loculated thoracic air collections in mechanically ventilated patients with acute respiratory distress syndrome.

OBJECTIVE: We report our experience with CT-guided percutaneous catheter drainage of loculated thoracic air collections in mechanically ventilated patients with acute lung injury or acute respiratory distress syndrome. MATERIALS AND METHODS: Nine critically ill patients had 17 air collections (13 pneumothoraces, three pneumatoceles, one tension pneumomediastinum) that either developed despite the presence of standard surgical chest tubes or were in loculated sites that were difficult to access. All nine patients were ventilated mechanically for a clinical diagnosis of acute respiratory distress syndrome. Catheter size ranged from 7- to 28-French. Response was measured by imaging follow-up, ventilatory parameters, and clinical outcome. RESULTS: On follow-up imaging studies, all 17 air collections were shown to have been evacuated successfully. Catheters remained in place for a mean of 11 days (range, 4-28 days). No major complications occurred. Sixteen air collections were treated successfully with CT-guided catheter placement alone; the remaining air collection, a pneumothorax, was treated with subsequent placement of a chest tube by the surgeon at the patient's bedside. No surgery was undertaken for the air collections. Improvement in gas exchange was documented by increase in the hypoxemia ratio (arterial oxygen pressure divided by the inspired fraction of oxygen) in seven of 12 drainages; the other drainages were accompanied either by no improvement or by deterioration. Eight (89%) of the nine patients eventually were extubated and discharged from the hospital. The ninth patient died. CONCLUSION: CT-guided percutaneous catheter drainage provided effective treatment for loculated thoracic air collections and obviated surgical intervention in these critically ill, high-surgical-risk patients.

Persistent pancreatocutaneous fistula after percutaneous drainage of pancreatic fluid collections: role of cause and severity of pancreatitis.

PURPOSE: To assess the relationship between the cause and severity of pancreatitis and the development of persistent pancreatocutaneous fistula (PPCF) after percutaneous drainage of pancreatic fluid collections. MATERIALS AND METHODS: Sixty patients (44 male, 16 female; age range, 10-74 years) were included in the study. The cause of pancreatitis was postoperative in 29 patients, alcoholism in 20 patients, biliary in six patients, hyperlipidemia in two patients, unknown in two patients, and trauma in one patient. Patients requiring intensive care unit treatment for their condition at the time of drainage were considered to have severe pancreatitis. Thirty-seven patients had mild pancreatitis, and 23 had severe pancreatitis. PPCF was defined as catheter drainage of pancreatic fluid of more than 10 mL/d for more than 4 weeks after catheter placement. RESULTS: PPCF developed in 27 of the 60 patients. It occurred in five of the six patients with biliary pancreatitis, 10 of the 20 with alcohol-related pancreatitis, and 10 of the 29 with postoperative pancreatitis (P > .2). The prevalence of PPCF was higher in patients with severe pancreatitis (n = 16 [70%]) than in those with mild pancreatitis (n = 11 [30%]). This difference was statistically significant (P < .002). CONCLUSION: Development of PPCF correlated with severity of pancreatitis, regardless of the cause of pancreatitis.

Percutaneous radiologic and endoscopic gastrostomy: a 3-year institutional analysis of procedure performance.

OBJECTIVE: The study was designed to evaluate the safety, efficacy, and usefulness of the performance of percutaneous radiologic (PRG) and endoscopic (PEG) gastrostomy. MATERIALS AND METHODS: This study involved a retrospective review of 182 percutaneous gastrostomy procedures (68 PRG, 114 PEG) performed over a 3-year period. Parameters analyzed included technical success, procedure duration, anesthetic requirements, incidental findings on endoscopy, and complications. RESULTS: The success rate for tube placement was higher for PRG than for PEG (100% versus 95%). PRG was subsequently performed in four of six patients in whom PEG procedures failed. Mean procedure duration was shorter for PRG than for PEG (32.9 min versus 39.1 min, p < .05). PRG was performed without conscious sedation (i.e., local anesthesia only) more frequently than was PEG (25% versus 0%, p < .001). The mean volume of doses of midazolam hydrochloride administered during PRG was two thirds of the volume of doses used during PEG. Incidental abnormalities were detected in 32 (30%) of the successful PEG procedures, 11 (10%) of which resulted in biopsy or medical therapy. No biopsy specimen showed evidence of malignancy. One (0.9%) patient received treatment other than gastric acid medication. Three (3%) major postprocedural complications occurred immediately after PEG and none (0%) occurred after PRG. CONCLUSION: The significant advantages of PRG over PEG included higher success rates, shorter procedure duration, and less conscious sedation required. PRG was also successful with patients for whom PEG failed.

Successful topical dissolution of cholesterol gallbladder stones using ethyl propionate.

Topical dissolution of cholesterol gallbladder stones using methyl tert-butyl ether (MTBE) is useful in symptomatic patients judged too ill for surgery. Previous studies showed that ethyl propionate (EP), a C5 ester, dissolves cholesterol gallstones rapidly in vitro, but differs from MTBE in being eliminated so rapidly by the liver that blood levels remain undetectable. Our aim was to test EP as a topical dissolution agent for cholesterol gallbladder stones. Five high-risk patients underwent topical dissolution of gallbladder stones by EP. In three patients, the solvent was instilled via a cholecystostomy tube placed previously to treat acute cholecystitis; in two patients, a percutaneous transhepatic catheter was placed in the gallbladder electively. Gallstone dissolution was assessed by chromatography, by gravimetry, and by catheter cholecystography. Total dissolution of gallstones was obtained in four patients after 6-10 hr of lavage; in the fifth patient, partial gallstone dissolution facilitated basketing of the stones. In two patients, cholesterol dissolution was measured and averaged 30 mg/min. Side effects were limited to one episode of transient hypotension and pain at the infusion site; no patient developed somnolence or nausea. Gallstone elimination was associated with relief of symptoms. EP is an acceptable alternative to MTBE for topical dissolution of cholesterol gallbladder stones in high-risk patients. The lower volatility and rapid hepatic extraction of EP suggest that it may be preferable to MTBE in this investigational procedure.

Percutaneous radiologic drainage of pancreatic abscesses.

OBJECTIVE: The purpose of our study was to review and report the patient selection, techniques, and results of percutaneous drainage of pancreatic abscesses by retrospective review. MATERIALS AND METHODS: Fifty-nine patients (46 men and 13 women) with a mean age of 44 years old had 80 pancreatic abscesses that were drained percutaneously under radiologic guidance (CT, n = 77; sonography, n = 2; and fluoroscopy, n = 1). Abscesses had a wide spectrum of causes, with alcoholic pancreatitis being most common, trauma second most common, and gallstones third. Ten patients had undergone surgery for pancreatic necrosis or abscess. Patients with pancreatic pseudocysts, necrosis, or acute fluid collections were excluded from this study. RESULTS: Of the 59 patients, 51 (86%) were cured with percutaneous drainage and antibiotic therapy. Of the patients who were not cured with percutaneous drainage, seven required surgery and one underwent repeat percutaneous drainage. In the 59 patients, complications included non-life-threatening bleeding in three patients. Ten of 59 patients (17%) had fistulas that spontaneously formed into the gastrointestinal tract. The duration of catheterization ranged from 4 to 119 days, with a mean duration of 33 days. The rate of mortality at 30 days after completion of percutaneous drainage was 8% (5 of 59). CONCLUSION: Percutaneous drainage was an effective therapy for this defined group of patients with pancreatic abscesses. Factors leading to the relatively high success rate described in this study likely included selection of patients; catheters of adequate size, number, and location; careful follow-up with appropriate catheter manipulations; and an integrated, cooperative approach whereby surgeons were willing to permit drainage to effect its benefits, rather than operating prematurely.

Drainage efficiency of double-lumen sump catheters and single-lumen catheters: an in vitro comparison.

PURPOSE: To compare the drainage efficiency of double-lumen sump catheters and single-lumen catheters in an in vitro model. MATERIALS AND METHODS: Four 12-F, 27.5-cm catheters were used in the study. Three of these had a double lumen with a 7-F internal diameter drainage lumen and one had a single lumen with an 8-F internal diameter drainage lumen. The sump hole opened internally to the drainage lumen in one catheter, opened externally in one catheter, and was occluded in one catheter. Catheters were connected to continuous low-wall suction and were immersed in water, viscous fluid, and viscous fluid with particles. The volume of fluid drained by each catheter was measured and compared. RESULTS: The single-lumen catheter with an 8-F internal diameter drainage lumen drained a volume equal to or larger than that for double-lumen catheters with a 7-F internal diameter drainage lumen for each type of fluid. The open sump of the double-lumen catheters may have decreased the catheter's drainage efficiency by allowing air to be suctioned into the catheter. CONCLUSION: Single-lumen catheters performed as well as or more efficiently than double-lumen catheters of the same outer diameter in this in vitro model.

Drainage catheters: in vitro comparison of internal retention mechanisms.

In five drainage catheters, internal retention mechanisms (locking pigtail [14 and 8 F], inflatable balloon [14 F], or wings [14 and 24 F]) were evaluated for resistance to and distortion from dislodgment. Catheters were inserted into simulated tissue, and weight was added until dislodgment occurred. Resistance to dislodgment increased when the mechanisms were locked; the locking pigtail supported the most weight. Distortion caused by dislodgment was minimal.

Treatment of postoperative lymphoceles with percutaneous drainage and alcohol sclerotherapy.

PURPOSE: To assess the efficacy and safety of percutaneous catheter drainage combined with alcohol sclerosis in the treatment of postoperative lymphoceles. PATIENTS AND METHODS: Thirteen patients with 14 postoperative symptomatic lymphoceles were treated. Drainage catheters were inserted under ultrasound (n = 13) or computed tomographic (n = 1) guidance. Lymphocele sclerosis was performed by instilling 10-100 mL of absolute alcohol into the lymphocele cavity and aspirating the alcohol after 30 minutes. Sclerosis sessions were carried out one to three times per day, usually three times per week. Catheter sinograms were obtained and prophylactic antibiotics administered. Imaging was repeated if symptoms or signs of recurrence developed. RESULTS: Successful drainage and sclerosis were achieved in all 13 patients. One patient with a recurrence was successfully treated with repeated drainage and alcohol ablation. No adverse effects of alcohol instillation were seen. The mean duration of catheterization was 36 days (range, 17-65 days; median, 30 days). CONCLUSION: Percutaneous drainage combined with alcohol ablation is a safe and effective treatment of postoperative lymphoceles.

Radiologic, endoscopic, and surgical gastrostomy: an institutional evaluation and meta-analysis of the literature.

PURPOSE: To evaluate the effectiveness and safety of radiologic, percutaneous endoscopic (PEG), and surgical gastrostomy. MATERIALS AND METHODS: This project involved 5,752 patients (837 patients underwent radiologic gastrotomy; 4,194, PEG; and 721, surgical gastrostomy). Seventy-two (47 male, 25 female; age range, 12-94 years) underwent gastrostomy within 1 year in this series (radiologic gastrostomy, n = 33; PEG, n = 35; surgical gastrostomy, n = 4). A meta-analysis of 5,680 additional cases from literature published from 1980 to the present was also performed. RESULTS: Rates of successful tube placement were higher for radiologic gastrostomy than for PEG in our series and in the meta-analysis (99.2% vs 95.7%, P < .001). Major complications occurred less frequently after radiologic gastrostomy in our series and in the meta-analysis (5.9% vs 9.4% for PEG and 19.9% for surgery, P < .001). Thirty-day procedure-related mortality rates were highest for surgery (2.5% vs 0.3% for radiologic gastrostomy and 0.53% for PEG, P < .001). CONCLUSION: Radiologic gastrostomy is associated with a higher success rate than is PEG and less morbidity than either PEG or surgery.

Malignant ureteral obstruction: treatment with metal stents--technique, results, and observations with percutaneous intraluminal US.

PURPOSE: To test the technical feasibility and results of placement of metal stents into ureters obstructed by extensive tumor. MATERIALS AND METHODS: Six consecutive patients (two men and four women, aged 35-66 years and with incurable malignancies) underwent insertion of metallic endoprostheses in nine obstructed ureters through percutaneous tracts. RESULTS: Metal stents were inserted without technical difficulty in all obstructed ureters. The stents functioned well in four patients. In two patients, the metal were not tolerated and plastic double-J stents were placed through the metal stents; this permitted effective functioning and withdrawal of the protective external catheter. Intraluminal ultrasonography depicted stent clogging and debris, dimensions of stent opening, and tumor level. CONCLUSION: Insertion of metal stents in the ureter is technically straightforward and was well tolerated by patients. However, the efficacy is variable, and a greater beneficial effect than is achieved with plastic stents is not established.

Percutaneous abscess drainage: current applications for critically ill patients.

Radiologically guided percutaneous abscess drainage (PAD) was first reported in 1977. Since this time, technological advances in imaging, improved catheter technology, and increased experience with the procedure have resulted in a tremendous expansion of the indications for PAD. This procedure currently has applications in nearly every organ system of the body. These changes have also contributed to improved success rates, with concurrent minimization of procedure-related complications. The advantages of PAD include simple, rapid performance; feasibility of bedside intensive care unit (ICU) performance; safety; avoidance of general anesthesia; and well-documented efficacy. This procedure has now become well entrenched in clinical medicine and probably ranks with the development of effective antibiotics as the most significant improvement in the treatment of abscesses in the past century. PAD is ideally suited for the treatment of critically ill ICU patients. We discuss technical developments over the past 15 years; general principles of patient preparation and catheters are also reviewed. Current applications of PAD in each organ system are discussed.