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.

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.

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.

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.

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.

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.

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.

Symptomatic hepatic cysts: percutaneous drainage and sclerosis

PURPOSE

To evaluate the authors' experience with treatment of symptomatic hepatic cysts by means of percutaneous catheterization and sclerosis.

MATERIALS AND METHODS

Twenty patients with 24 symptomatic hepatic cysts underwent percutaneous drainage and sclerosis. Ten patients had polycystic disease, and 10 had solitary cysts. Sclerosants used were alcohol, tetracycline, doxycycline, or a combination.

RESULTS

Twenty-one of 24 cysts in 17 of 20 patients were treated successfully. Treatment was unsuccessful in three patients: one patient with innumerable medium-size and small cysts, one patient in whom only a needle was inserted (no catheter), and one patient with a cystic metastasis (rather than a simple cyst) that recurred. Complications included pleural effusion in two patients and secondary infection in one patient. The range of blood alcohol levels was 0-0.8 mg%.

CONCLUSION

Percutaneous catheter drainage with sclerosis is an effective method of therapy for symptomatic hepatic cysts; careful patient selection is essential for proper therapy.

Ultrasound guided biopsy of nonpalpable and difficult to palpate thyroid masses

We reviewed our experience with ultrasound-guided biopsies of masses of the thyroid gland that were either nonpalpable or difficult to localize by palpation to evaluate the technique and correlate the results. Thirty-two biopsies were performed upon 25 patients whose clinical presentations were palpable nodule (six patients), throat discomfort (two patients), postpartial thyroidectomy follow-up evaluation (two patients), incidental discovery of a mass--by ultrasound of the neck (two patients), roentgenogram of the chest (two patients), computed tomography of the chest (one patient) and during tracheostomy placement (one patient). Other presentations were eliminate infection (one patient), odynophagia (one patient), hoarseness (one patient), cold nodule on a nuclear medicine study (one patient), hyperparathyroidism (one patient), rule out metastasis from carcinoma of the colon (one patient), persistent cough (one patient), enlarged thyroid gland (one patient) or family history of carcinoma of the thyroid gland (one patient). Fifteen patients had nuclear medicine studies showing either a cold nodule (ten patients), multinodular goiter (one patient), normal examination (two patients), hot nodule (one patient) or no thyroid gland activity (one patient). The ultrasound examinations showed either a hypoechoic nodule (25 patients), inhomogeneous or mixed echogenic nodule (six patients) or a hyperechoic nodule with hypoechoic rim (one patient). The nodules ranged in size from 3 milliliters to 7 centimeters. Twenty-six lesions were less than 3 centimeters in diameter; of the other six, four were substernal goiters. Six patients had a previous nondiagnostic biopsy directed by palpation only. Biopsy was performed using real-time ultrasound guidance with various needles. One patient had a small hematoma, which was the only complication in the study. The results of the biopsies were diagnostic in 26 of 32 patients. The final diagnosis was benign follicular cells (ten patients), adenomatous nodule (seven patients), follicular neoplasm (three patients), colloid cyst (two patients), aspergillus (two patients), fibrosis (one patient) and papillary carcinoma (one patient). Six of the biopsies yielded unsatisfactory specimens. One of the patients with a diagnosis of benign follicular cells on biopsy had a follicular carcinoma after surgical pathologic factors were obtained; that was the only false-negative result. We conclude that ultrasound-guided biopsy of the thyroid is a safe and useful method of evaluating nonpalpable and difficult to palpate thyroid masses.

Anterior mediastinal lesions: transsternal biopsy with CT guidance. Work in progress

PURPOSE

To assess the technique, results, and patient tolerance of transsternal biopsy of anterior mediastinal lesions under computed tomographic (CT) guidance.

MATERIALS AND METHODS

Seven patients (four women and three men) with anterior mediastinal lesions underwent eight transsternal biopsies. Patients were included in the study if there was a risk of injury to internal mammary vessels or a danger of tranversing the lung by the biopsy needle. Patients were specifically questioned about the pain caused by the transsternal needle. A pain scale was not used. Conscious sedation and local anesthesia requirements provided gross evaluation of the patients' tolerance to the procedure. CT scans were used to guide and confirm optimal alignment of the transsternal needle with the lesion.

RESULTS

Patients experienced minimal discomfort when the sternum was traversed. No instances of pneumothorax, postprocedural pain, or infection were encountered. In six of the seven patients, biopsy specimens were diagnostic.

CONCLUSION

The transsternal approach for biopsy of anterior mediastinal lesions appears safe and is well tolerated.

Complications of laparoscopic cholecystectomy: coordinated radiologic and surgical management in 21 patients

The authors describe their experience in management of bile duct injuries (n = 11), bile leaks or abscesses (n = 11), and bleeding (n = 1) as complications of laparoscopic cholecystectomy in 21 patients. Clinical presentations included jaundice, sepsis, pain, abdominal distention, and persistent gallstones. Twelve patients underwent operative cholangiography, three underwent conversion to open cholecystectomy, and 12 reoperations were performed in nine patients before interventional radiologic procedures, which included diagnostic percutaneous transhepatic cholangiography (n = 13), percutaneous biliary drainage (PBD) (n = 13), percutaneous stricture dilation (n = 3), stent insertion (n = 1), percutaneous abscess or biloma drainage (n = 19), and gallstone removal (n = 1). Each procedure was technically successful. Clinical improvement occurred in 18 of 19 patients. PBD was used as an operative guide before reconstructive surgery in two patients. Reoperation was unnecessary in 10 of 21 patients (48%). One patient died of fungal sepsis and pulmonary complications. This radiologic-surgical approach provided rapid and safe management of these complications.

Treatment of pancreatic pseudocysts with percutaneous drainage and octreotide. Work in progress

In an attempt to decrease catheter drainage of pancreatic pseudocysts, a combined regimen of percutaneous drainage and administration of octreotide acetate was used in eight symptomatic patients. Indications for the combined therapy were pseudocyst recurrence (four patients), pancreatic fistula from percutaneous drainage (two patients), or elective treatment to restrict pancreatic drainage. Octreotide acetate was administered subcutaneously in doses of 50-1,000 micrograms three times a day. The drug was well tolerated and produced only limited adverse effects in four patients: pain at the injection site, hypoglycemia, diarrhea, headaches, and lower-extremity edema (more than one adverse effect was experienced by each patient). The combined use of percutaneous drainage and administration of octreotide was effective in seven patients and failed in one patient who had distal pancreatic duct occlusion. In five patients, catheter drainage decreased to no measurable amount by a mean of 13.8 days. These results suggest octreotide is effective in decreasing the output from pancreatic pseudocysts drained percutaneously.

Acute effects of topical methyl tert-butyl ether or ethyl propionate on gallbladder histology in animals: a comparison of two solvents for contact dissolution of cholesterol gallstones

Experiments were performed in anesthetized rabbits and piglets to assess gallbladder mucosal injury during irrigation with methyl tert-butyl ether, a C5 ether, or ethyl propionate, a C5 ester--two organic solvents used in the contact dissolution of cholesterol gallstones. In 44 New Zealand White rabbits, the gallbladder was exposed to individual solvents or saline solution through a transhepatic catheter for 2 hr. Gallbladders were then harvested and fixed immediately or after a recovery period of 1, 4 or 8 days. Tissue sections were examined under light microscopy, and severity of injury was graded with predefined criteria by two pathologists blinded to the animals' treatment regimens. Histological assessment showed severe mucosal injury such as necrosis of the cells at the villus tips immediately after 2 hr of exposure to either solvent. After 4 days, injury had decreased significantly; after 8 days, complete mucosal healing had taken place. A similar study was performed in 32 piglets. Solvent or saline solution was oscillated in and out of the gallbladders of these piglets with a computer-controlled syringe pump at a pressure less than the leakage pressure of the gallbladder. Histological assessment was performed on tissue samples obtained immediately after the procedure or 8 days later. Both solvents caused severe mucosal injury; however, after 8 days complete mucosal healing had occurred, so that gallbladders exposed to solvent were indistinguishable from gallbladders exposed to saline solution, which was used as control. We conclude that both methyl tert-butyl ether and ethyl propionate cause moderate to severe epithelial injury but that the gallbladder epithelium regenerates within a few days.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of the stopcock on the efficiency of percutaneous drainage catheters: laboratory evaluation

The effects of stopcocks on percutaneous fluid drainage were tested in a laboratory model by using a standard stopcock (6-French inner diameter) and a prototype stopcock (9-French inner diameter) connected to 8-, 10-, 12-, 14-, and 16-French catheters. Catheters were immersed in water alone or in viscous fluid with particulate matter, and the system was connected to low wall suction or gravity drainage. The average volume of fluid aspirated in a given period with and without a stopcock was compared for each catheter. The standard stopcock decreased drainage efficiency for these catheters by 13-42%. This decreased drainage efficiency was worse with the larger catheters. Particulate fluid blocked the stopcock connection for all catheters. With the prototype stopcock, drainage of water alone was reduced by 0-9% for the catheters of different sizes. Particulate fluid did not obstruct the prototype stopcock with any size catheter. With gravity drainage, the volume of water aspirated was reduced by 12-42% with the standard stopcock and by 3-6% with the prototype stopcock. These data suggest that stopcock connections greatly influence the efficiency of the percutaneous drainage systems. Stopcocks with larger inner diameters may improve drainage over that achievable with the stopcocks that are currently available.

Interventional radiology in the chest

Interventional radiologic techniques offer many options and benefits in the care of patients with thoracic disorders. Imaging-guided catheter techniques provide heretofore unsurpassed precision and accuracy in performance of these procedures. Improved efficacy, with reduced morbidity is the goal and usually the result for the patient.

CT guidance for percutaneous gastrostomy and gastroenterostomy

The authors describe the value of computed tomographic (CT) guidance for percutaneous gastrostomy (PG) or gastroenterostomy (PGE) in 22 patients with anatomic or pathologic difficulties precluding fluoroscopic guidance. Indications for PG or PGE were decompression for gastrointestinal obstruction (n = 15) or for feeding (n = 7). Thirteen patients previously underwent an unsuccessful attempt at or had been rejected as unsuitable for percutaneous endoscopic gastrostomy. CT guidance was selected because of inability to pass a nasogastric tube due to esophageal obstruction (n = 4), inability to tolerate gastric distention (n = 1), abnormal morphology in or around the stomach (n = 16), or simultaneous performance of a PG in one patient who was undergoing emergency CT-guided abscess drainage. Catheters were placed successfully in all 22 patients. No major complications occurred. CT is valuable for PG or PGE when anatomic or pathologic problems make fluoroscopic or endoscopic puncture unsafe or impossible.

Inadvertent ligation of the aberrant right hepatic duct at cholecystectomy: radiologic diagnosis and therapy

Aberrant right hepatic ducts are the most common biliary tract anomaly and are particularly susceptible to injury at cholecystectomy because of their critical location. The authors report radiologic diagnosis and therapy in five cases of inadvertent ligation of this duct at cholecystectomy. The diagnosis was unsuspected prior to the radiologic studies in each patient. Four patients experienced recurrent cholangitis; one patient had chronic pain as the only symptom. Prior to diagnosis, the duration of symptoms ranged from 2 weeks to 126 months. Findings at ultrasound, computed tomography, and percutaneous transhepatic cholangiography with differential biliary pressures helped establish the diagnosis in each patient. Findings at endoscopic retrograde cholangiopancreatography were nondiagnostic in four patients. Percutaneous biliary drainage provided palliation of symptoms, improved each patient's condition prior to reconstructive surgery, and provided an intraoperative landmark for the surgeon. Two patients had associated bilomas, one of which was infected and was drained percutaneously. All patients survived and recovered without further complications.

Percutaneous gallbladder puncture and cholecystostomy: results, complications, and caveats for safety

The authors describe the technical results in 127 patients who underwent diagnostic gallbladder puncture and percutaneous cholecystostomy. The procedures were performed for a variety of indications including treatment of acute calculous or acalculous cholecystitis, drainage of obstructive jaundice or gallbladder perforation, percutaneous removal or dissolution of gallstones, diagnostic cholecystocholangiography, and gallbladder biopsy. Successful completion of the intended procedure was achieved in 125 of 127 patients (98.4%). Major complications occurred in 11 patients (8.7%); these included bile peritonitis, bleeding, vagal reactions, hypotension, catheter dislodgement, and acute respiratory distress. Minor complications were noted in five patients (3.9%). The 30-day mortality rate was 3.1% (four patients); the deaths were due to the underlying diseases. The data help support percutaneous cholecystostomy as a primary interventional radiologic procedure that has an extremely high likelihood of technical success. Recommendations to minimize or avoid complications are presented.

Percutaneous intraluminal US in the gallbladder and bile ducts

The authors describe their initial experience with a dedicated intraluminal ultrasound (US) device that was coupled to a catheter and introduced percutaneously into the gallbladder and/or bile ducts. Access was created with interventional radiologic techniques in 22 patients and at laparoscopy in four patients. Thirty-one examinations in 26 patients revealed information on normal anatomy, pathologic processes, and responses to therapy. The pathologic processes seen included bile duct and gallbladder debris, stones, ductal strictures, and tumors. Additional information provided with this technique over other diagnostic studies included differentiation of intraluminal filling defects, examination of areas inaccessible to conventional imaging, and observations about the walls of the ducts and gallbladder. Percutaneous US examination of metallic stents within the bile ducts and of filling defects in the ducts at laparoscopic cholecystectomy was of particular interest and altered subsequent therapy. The procedure is simple, straightforward, and devoid of complications. While refinements and improvements are needed, this diagnostic technique holds promise.

Percutaneous drainage of tubo-ovarian abscesses

The authors performed percutaneous drainage of 27 tubo-ovarian abscesses (TOAs) in 16 patients in whom medical therapy with triple antibiotics prior to catheter drainage had not been successful. Percutaneous drainage was successful in 15 of 16 patients (94%). One patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy 3 days after catheter placement because of persistent symptoms and lack of drainage from the catheter; at laparotomy, a large infected phlegmon was found. Two patients had recurrent disease at 3 and 4 months after catheter placement. Bilateral salpingectomy was performed in one patient and total abdominal hysterectomy and bilateral salpingo-oophorectomy in the other. One of these patients had cervical carcinoma, and the other had a long history of recurrent pelvic inflammatory disease and TOAs. The long-term avoidance of surgery was 81.2%. Access routes for catheter drainage were through the anterior abdominal wall for 10 abscesses, through the posterior transgluteal route for 11, and through the transvaginal route for six. Duration of drainage was 1-20 days (mean, 6 days). Complications consisted of transient sciatic pain in two patients and mild bacteremia in one. The results indicate that percutaneous drainage of TOAs is effective in patients in whom medical therapy is not successful.

A simple method to lock large mushroom-tip catheters

Dislodgment is a major drawback with large-bore Malecot catheters. A locking mechanism with a suture affixed to the distal portion of the mushroom tip is described. In a 32-month period, 17 Malecot catheters with locking mechanisms were placed in 15 patients. One catheter dislodged as a result of suture failure. A variation in design prevented subsequent failure of sutures. This simple locking mechanism prevents collapse of the catheter wings and thereby maintains catheter placement.

Symptomatic renal obstruction or urosepsis during pregnancy: treatment by sonographically guided percutaneous nephrostomy

Seven pregnant women with symptomatic hydronephrosis had sonographically guided percutaneous nephrostomy for pyosepsis (five patients) or for pain with azotemia (two patients with renal transplants). Antibiotics had been ineffective in controlling pyosepsis in each patient; retrograde ureteral catheterization via cystoscopy was unsuccessful in one patient. After percutaneous nephrostomy, prompt clinical improvement was observed in all patients (i.e., sepsis was relieved and pain abated). Labor was not induced in any of the patients, and no adverse effects occurred to any fetus or mother. Eleven (eight percutaneous nephrostomy, three catheter exchanges) of the 12 procedures were done without conventional radiography and with sonographic guidance alone. After percutaneous nephrostomy, maneuvers to obtain a diagnosis and to treat the obstruction (if necessary) were delayed until after delivery. The causes of ureteral obstruction were calculi (four patients) and a gravid uterus (three patients). After delivery, stones were removed either percutaneously (one patient) or cystoscopically (two patients) or passed spontaneously (one patient); resolution of obstruction by the gravid uterus was proved by Whitaker test after delivery. Sonographically guided percutaneous nephrostomy is an effective and safe method to treat pregnant women who have symptomatic obstructive hydronephrosis associated with either pyosepsis or azotemia. The procedure is rapid, requires minimal anesthesia, has no radiation, and is safe for the fetus. The technique is a useful and perhaps preferable alternative to more invasive surgical therapy or retrograde stenting.

Imaging of the percutaneous cholecystostomy tract: observations and utility

The technique and observations in 28 patients who underwent imaging of the percutaneous cholecystostomy (PC) tract are described. Imaging of the tracts was performed by injecting contrast material through an end-hole dilator during catheter removal (n = 13) or through an end-hole dilator with a side adapter over a thin guide wire (n = 15); the latter method permitted simple catheter reinsertion if the tract was poorly formed. Catheters were removed between 9 and 158 days (mean, 36.6 days; median, 29.5 days) after PC. Twenty-three patients had well-formed tracts and five patients did not. Among the five patients with a poorly formed tract, two experienced no sequela as a result of catheter withdrawal, two underwent immediate catheter reinsertion, and one developed bile peritonitis; this last patient was treated with repeated PC and antibiotics. All patients in whom a catheter was placed for at least 20 days had a well-formed, intact tract. Imaging of the PC tract is helpful to identify patients who have an immature tract. In a patient with a poorly formed tract, catheter reinsertion may be advisable to prevent bile leakage and peritonitis.

US-guided transvaginal drainage of pelvic abscesses and fluid collections

Ultrasound (US)-guided transvaginal needle or catheter drainage was performed in 14 women for a variety of pelvic abscesses and fluid collections; tubo-ovarian abscesses and postoperative collections were most common. Diagnosis was achieved in all 14 patients (100%), including one patient with suspected ovarian carcinoma who underwent only diagnostic needle aspiration and no therapeutic drainage. Abscesses or fluid collections were evacuated in 13 of 13 patients (100%) with either needle (n = 7) or catheter (n = 6) drainage (with appropriate antibiotics). Twelve of the 14 patients (86%) were spared an operation; surgery was undertaken in two patients for a persistent tubo-ovarian phlegmon. No major complications were associated with drainage. Catheters were removed an average of 6.7 days after insertion. The success, safety, and advantages of US-guided transvaginal drainage in our early experience suggest its use as an alternative to standard percutaneous catheter procedures to diagnose and drain certain pelvic abscesses and fluid collections.

Percutaneous dissolution of gallstones

Contact dissolution with MTBE is an effective and safe method to treat symptomatic patients with cholesterol gallstones. Personnel, time, and safety factors have limited widespread use of the procedure. With current competing methods to treat gallstones, it is likely that MTBE use will be reserved for those patients who elect percutaneous therapy due to fear of surgery or anesthesia and in those elderly patients who are compromised by underlying medical conditions.

Thin-layer chromatography to monitor cholesterol gallstone dissolution by methyl tert-butyl ether

We describe a simple and inexpensive method of monitoring methyl tert-butyl ether (MTBE) dissolution of cholesterol gallstones with thin-layer chromatography (TLC) in 10 patients. TLC is a routine semiquantitative laboratory method that can be used to measure the cholesterol concentration present in the MTBE and bile mixture aspirated through the cholecystostomy catheter during gallstone dissolution. TLC is practical in the clinical setting because it can be used to determine if gallstone dissolution is occurring and when MTBE lavage is no longer effective. TLC is performed in the laboratory with routine material and is completed in 15 min. Each TLC measurement costs about $1. The procedure provides objective and specific chemical information on effectiveness and progression of gallstone dissolution, apart from the radiologic and sonographic studies. In our study, TLC signaled effective dissolution in the initial phase of gallstone dissolution by detecting large amounts of cholesterol in the MTBE and bile mixture even before a visible change in size or shape of the stone became apparent by transcatheter cholecystography or by sonography (six of 10 patients). Conversely, lack of cholesterol on TLC after 1 hr or more of MTBE infusion indicates that the stones are pigmented or contain substantial calcium. This means that dissolution with MTBE will be ineffective and that solvent infusion should be terminated. In those cases in which dissolution is progressing well, when TLC shows decreasing amounts of cholesterol in the effluent, only residual fragments insoluble to MTBE remain or the stone is sequestered from MTBE; at this point, solvent infusion should be discontinued or the catheter must be repositioned. Monitoring the rate of cholesterol dissolution by TLC provides important complementary information to cholecystography and sonography during gallstone treatment with MTBE.

Human gallbladder morphology after gallstone dissolution with methyl tert-butyl ether

The effects of methyl tert-butyl ether exposure on the human gallbladder in five patients who were treated for gallstones by contact dissolution is described. Two patients underwent cholecystectomy within 1 week of methyl tert-butyl ether treatment, one patient 2 weeks after, another 10 weeks after, and one 12 weeks after. Indications for cholecystectomy were bilirubinate stones (resistant to methyl tert-butyl ether), catheter dislodgement, bile leakage, and gallstone recurrence (2 patients). Gallstones were dissolved completely in three patients, there was approximately 50% stone reduction in one patient, and no dissolution occurred in the fifth patient. Each gallbladder was examined grossly and histologically. Electron microscopic evaluation was performed in one cases. Typical inflammatory findings of chronic cholecystitis were observed in each gallbladder and were most conspicuous in the submucosa; the mucosal and serosal surfaces were intact. Mild acute inflammatory changes were noted in the submucosa in the two patients with the shortest interval between methyl tert-butyl ether administration and cholecystectomy. There were no ulcerations in the mucosa and no unusual wall thickening or fibrosis in any patient. These observations support the safety of methyl tert-butyl ether perfusion in the human gallbladder; the mild acute changes may be a transient and reversible phenomenon.

Gallbladder perforation and bile leakage: percutaneous treatment

Three patients with spontaneous gallbladder perforation and one with an iatrogenic bile leak causing bile peritonitis were treated successfully by means of percutaneous catheter drainage. Three patients had cholelithiasis as the cause of perforation; the fourth patient had previously undergone gallstone dissolution with methyl tert-butyl ether lavage and developed bile peritonitis a few hours after removal of the catheter. In three patients, a percutaneous cholecystostomy catheter provided successful decompression; in the fourth patient, drainage was performed with a percutaneous sump catheter in the subhepatic space adjacent to the gallbladder. No specific complications occurred. Follow-up was performed at 1, 12, 22, and 59 months, respectively. To date, one of the four patients has undergone elective cholecystectomy (1 month after drainage). The remainder of the patients are asymptomatic. This preliminary experience suggests that the severe complication of gallbladder perforation and bile leakage may be treated, at least temporarily, by means of percutaneous drainage.

Lung abscess: CT-guided drainage

Lung abscesses were drained by means of catheters guided by computed tomography (CT) in 19 patients who still had sepsis despite standard medical therapy; all patients had received antibiotics for at least 5 days, and 11 of the 19 patients had undergone bronchoscopy. The abscess was cured (by clinical and radiographic criteria) in all 19 patients (100%), and surgery was avoided in 16 of the 19 patients (84%). Three patients underwent surgery for removal of organized tissue or decortication after the lung abscess was evacuated. Complications included a hemothorax that required a chest tube in one patient and three minor complications (a clogged catheter in two patients and transient elevation of intracerebral pressure in one patient). The hemothorax occurred in one of two patients in whom the catheter traversed normal lung. The percutaneous drainage catheters traversed juxtaposed abnormal pleura on route to the abscess in 17 of the patients. CT-guided drainage of lung abscess is an effective method to treat lung abscesses that are refractory to conventional therapy; the procedure should obviate major operation in most patients. A catheter route through abscess-pleural syndesis is preferable, and CT is useful for planning this route.

CT-guided transthoracic needle biopsy

CT-guided biopsy of pulmonary and mediastinal lesions is safe and effective. It is most valuable in those cases in which fluoroscopic guidance is not possible due to resolution or anatomic consideration. CT guidance permits puncture of lesions as small as 0.5 cm, typically not seen fluoroscopically. Sensitivity of biopsy in malignant lung lesions in our series of 83 cases was 92%. Pneumothorax is the most frequent complication (10-60%) and requires chest tube insertion in 5-15% of patients.

The benefits of percutaneous cholecystostomy for decompression of selected cases of obstructive jaundice

Eleven selected patients with obstructive jaundice underwent percutaneous cholecystostomy (PC) for decompression. Ten of these patients had the constellation of distal common duct obstruction, nondilated or minimally dilated intrahepatic ducts, and a distended gallbladder; one patient with a bleeding dyscrasia had moderately dilated intrahepatic bile ducts. All procedures were successful and effective, and 10 of 11 cholecystostomies were performed within 5-15 minutes. No specific complications occurred. The success, ease, and safety of the procedure indicate primary use of PC for biliary decompression when the intrahepatic bile ducts are minimally dilated or nondilated, because standard transhepatic biliary drainage may be difficult in these cases. Because cannulation of the cystic duct and hence internalization through the tumor may be difficult, PC may be most valuable preoperatively, or before standard percutaneous biliary drainage, or as an alternative to endoscopic drainage. This is a rapid and safe method with which to achieve biliary decompression, especially with minimally dilated or nondilated intrahepatic bile ducts.

The role of interventional radiology for complications of cholecystectomy

This report summarizes diagnostic and therapeutic radiologic procedures in 45 patients who suffered major complications from cholecystectomy. Complications were divided into (1) bile duct injury or ligation and (2) a variety of pathologic fluid collections. Specific lesions were bile duct injury (n = 6), accidental bile duct ligation (n = 12), ductal stricture (n = 12), abscess (n = 11), biloma (n = 7), hematoma (n = 5), infected pancreatic pseudocyst (n = 3), and stones (n = 2). Presenting problems were sepsis, jaundice, and intermittent cholangitis. The patients underwent 104 interventional radiologic procedures including 29 percutaneous transhepatic cholangiograms, 21 percutaneous biliary drainages, 12 balloon dilatations of strictures, drainage of 11 abscesses, 8 bilomas, 5 hematomas, and 3 pancreatic pseudocysts. Stones were removed by baskets in 2 patients; 12 pressure and perfusion studies were performed. One hundred of 104 procedures were successful; there was one failed biliary drainage, one unsuccessful stricture dilatation, one unsuccessful hematoma drainage, and one recurrent biloma. Thirty patients were spared another operation. The percutaneous procedures were beneficial although not curative in 14 of 15 patients who underwent reoperation; in those patients the procedures helped to establish a diagnosis, improve the patient's preoperative status, or serve as a landmark for the surgeon to locate and repair the ligated or injured duct. One patient died after reoperation, a 2.2% mortality rate. Sectional imaging studies combined with interventional radiologic procedures help to diagnose promptly and effectively treat major complications of cholecystectomy. These interventional procedures either cure the complication and obviate reoperation or aid the surgeon by relieving sepsis and jaundice before reoperation and providing an intraoperative guide for bile duct reconstruction.