Technical report: Hickman catheter rescue

Nineteen malfunctioning or incorrectly positioned Hickman catheters from a series of 320 catheter placements were referred to the radiology department for salvage. Successful catheter 'rescue' was achieved on 14 occasions (73.6%). Eight catheters were repositioned, five were replaced and thrombolysis was successful in a patient with subclavian vein thrombosis. Catheter repositioning techniques are reviewed and a new technique for catheter replacement using the existing venous access and subcutaneous tunnel is described.     

Pericardial tamponade and death from Hickman catheter perforation

In February 1995, a 56-year-old female was taken to the operating room for routine placement of a Hickman catheter. Her internist planned palliative chemotherapy for metastatic breast cancer. Using the Seldinger technique, the right subclavian vein was entered and a Hickman catheter was placed. Shortly after extubation and arrival in the postoperative recovery unit, the patient had respiratory and cardiac arrest. Resuscitative efforts, including chest tube placement and pericardiocentesis, were unsuccessful. Autopsy findings included perforation of the superior vena cava, with extension of the catheter in the pericardial sac and associated effusion. Despite the low reported incidence of perforation during placement of central venous catheters, we recommend confirmation of placement by fluoroscopy and instillation of radiopaque dye because of the high mortality associated with this complication.     

Mycobacterium neoaurum infection of a Hickman catheter in an immunosuppressed patient

Mycobacterium neoaurum is a rapidly growing mycobacterium that has only once before been reported as a cause of bacteremia in an immunocompromised patient. We report on a patient who developed bacteremia after an allogeneic bone marrow transplantation and from whose blood (taken via a Hickman catheter) M. neoaurum was isolated on three separate occasions. There was a clinical response to therapy with ticarcillin/clavulanate and tobramycin, and the organism appeared to be susceptible to the former in vitro. The Hickman catheter was removed because of persistence of the organism in cultures of blood taken from the catheter. M. neoaurum may be a rare cause of infections in immunocompromised patients and should not be dismissed as an environmental contaminant.     

The peripherally inserted central catheter: a retrospective look at three years of insertions

The advent of intravenous therapies administered in the home setting has created a demand for the peripherally inserted central catheter (PICC). A variety of PICCs is now on the market, offering choices of insertion methods as well as size and length. This article represents a retrospective look at 858 PICCs inserted over a 3-year period, using three insertion methods: 1) the Seldinger technique, 2) the peel-away sheath, and 3) the break-away needle. A brief history of PICCs along with problems encountered, an account of PICCs in immune-suppressed patients, and principles of catheter management are presented.     

Case report: A rare complication of Hickman line insertion

The objective evaluation of smell is the least used functional ear, nose and throat exploration. Evoked potentials can be recorded after chemical olfactory stimulation using a method similar to recording cortical auditory evoked potentials. Our results with this technique and peppermint oil as the stimulant were fully satisfactory. In 10 patients with normal smell, a characteristic wave with a long latency was recorded in the absence of auditory and visual stimuli. In contrast, in 10 anosmic patients this characteristic recording was absent. The easy recording technique proposed here can be useful for olfactory assessment of objective disorders, detection of malingers, and medical-legal reports.     

A malpositioned CVP catheter

A 2-year-old boy was scheduled for patch closures of ASD and VSD. After anesthesia induction, infection of a double lumen central venous catheter (5 Fr, Arrow) was tried into the superior vena cava through the right jugular vein by Seldinger's method. We confirmed the placement of the catheter by drawing a small amount of blood. After the operation, chest X-ray examination in ICU revealed the misplacement of the catheter into his right intrapleural space. The catheter was left overnight to be used as a drainage route of a possible bleeding. Next morning, no abnormal finding in his chest X-ray and stable circulatory and respiratory conditions were found and we proceeded to extubate his endotracheal tube and take away the catheter. Two hours after the removal of the catheter, the boy showed forced respiration. He became cyanotic rapidly and then he needed emergency intubation. Following chest X-ray examination and an aspiration of intrapleural space revealed a severe hemothorax of the right side, where catheter had been inserted. The boy recovered without any disorders. This case suggests the importance to confirm the placement of CVP catheter, and to prevent the possible complications due to the malpositioned catheter.     

A new cholangiography catheter

A new cholangiography catheter has been evaluated in 66 consecutive gall bladder operations. The catheter has an integral moulded cone shaped locking attachment and a tap to reduce the risk of air bubbles entering the biliary tree. The catheter coulc not be introduced into the duct in 10% of patients. In the remainder both surgeon and radiologist were satisfied with the cholangiogram.     

Central venous catheter replacement strategies: a systematic review of the literature

OBJECTIVE: To evaluate the effect of guidewire exchange and new-site replacement strategies on the frequency of catheter colonization and infection, catheter-related bacteremia, and mechanical complications in critically ill patients. DATA SOURCES: We searched for published and unpublished research by means of MEDLINE and Science Citation Index, manual searching of Index Medicus, citation review of relevant primary and review articles, review of personal files, and contact with primary investigators. STUDY SELECTION: From a pool of 151 randomized, controlled trials on central venous catheter management, we identified 12 relevant randomized trials of catheter replacement over a guidewire or at a new site. DATA EXTRACTION: In duplicate and independently, we abstracted data on the population, intervention, outcome, and methodologic quality. DATA SYNTHESIS: As compared with new-site replacement, guidewire exchange is associated with a trend toward a higher rate of catheter colonization (relative risk 1.26, 95% confidence interval 0.87 to 1.84), regardless of whether patients had a suspected infection. Guidewire exchange is also associated with trends toward a higher rate of catheter exit-site infection (relative risk 1.52, 95% confidence interval 0.34 to 6.73) and catheter-related bacteremia (relative risk 1.72, 95% confidence interval 0.89 to 3.33). However, guidewire exchange is associated with fewer mechanical complications (relative risk 0.48, 95% confidence interval 0.12 to 1.91) relative to new-site replacement. Exchanging catheters over guidewires or at new sites every 3 days is not beneficial in reducing infections, compared with catheter replacement on an as-needed basis. CONCLUSIONS: Guidewire exchange of central venous catheters may be associated with a greater risk of catheter-related infection but fewer mechanical complications than new-site replacement. More studies on scheduled vs. as-needed replacement strategies using both techniques are warranted. If guidewire exchange is used, meticulous aseptic technique is necessary.     

Ruptures of double-J ureteral catheter. Our experience and review of the literature

Follicular carcinoma, in association with other prognostic factors, identifies a class of "high-risk" patients in which a more aggressive treatment is indicated. In fact, in patients operated on for follicular carcinoma bone metastases, also many years after primary surgery, are reported. A case of skull metastases in a young women occurred 3 years after a near total lobectomy for follicular thyroid carcinoma is described. After six years the patient underwent total thyroidectomy, resection of skull metastases, radiometabolic therapy with I131 180 m Ci; now she is disease free at three years of follow-up. The biology of metastases in thyroid follicular carcinoma, risk factors and diagnostic and therapeutic controversies are analyzed. Good prognostic factors are considered age < 45 years, good degree of differentiation of primary tumor, small size of bone metastases and early appearance after primary diagnosis. The conclusions is drawn that bone metastases are the worst prognostic factors. In case of single lesion, surgical treatment allows good results.     

A multicentre comparative evaluation of catheter valves

Catheter valves are an alternative to leg bags for urine drainage, but no studies have yet been published which have compared the performance of different valves. This study was undertaken to evaluate the performance of the seven catheter valves available on the UK market in April 1996. The study was carried out by the Continence Products Evaluation (CPE) Network funded by the Medical Devices Agency (Department of Health). Each valve type was tested for 1 week by 19-36 cognitively unimpaired and manually dextrous subjects recruited from 11 test centres. At the end of each week, subjects completed an evaluation form (based on a three-point rating scale) to record product performance. The same catheter valves were also tested for ease of opening/closing by 33 subjects (mostly catheter users) who had some manual impairment. Performance scores varied widely between products. It was found that, to be successful, a valve needs to be easy to manipulate, leak-free, comfortable and inconspicuous. Prescribers need to be aware of the strengths and limitations of different valves for appropriate product selection.     

A double lumen suprapubic urodynamic catheter

A 7.5 FG double lumen suprapubic urodynamic catheter has been developed to avoid the effects of urethral catheterization and provide reliable continuous pressure monitoring. The device is an adapted central venous catheter which is easily introduced through a peel-away sheath, after the insertion of a guide wire.     

Multiplex polymerase chain reaction of Alu polymorphic insertions

Alu sequences are present in humans in excess of 500,000 copies per haploid genome and represent the largest family of short interspersed repetitive elements (SINEs). These mobile genetic elements are ancestrally derived from the 7SL RNA gene and move throughout the genomes of primates by retroposition. Polymorphic Alu insertions have proven to be useful for population studies, paternity determinations and forensic applications. Additionally, a simple polymerase chain reaction (PCR)-based assay has been established to examine these polymorphisms. In the present study, we have applied the technique of multiplex polymerase chain reaction to the Alu polymorphic system. Duplex and triplex PCR reactions were performed for the analysis of five different Alu polymorphic loci in different combinations. This study represents a starting point for further experimentation to improve and eventually optimize Alu multiplex PCR.     

KH560改性制备防吸湿煅白及其机理研究

以KH560为改性剂对煅白进行改性制备防吸湿煅白,并研究最佳改性条件和改性机理。结果表明,当改性剂添加量为每克煅白0.025mL、改性温度50℃、改性时间8h时,煅白的接触角由37.04°增加到100.05°;吸湿率在720min内由2.01%降低到0.35%,降低了82.5%。     

560 mm铜带冷轧机组电气控制系统

本文介绍560mm可逆铜带冷轧机组电气控制系统的原理及系统组成。     

唐钢2560m^3高炉工程工艺设计特点

唐钢２５００ｍ＾３高炉设计中采用了皮带机上料,并罐式无料钟炉顶,炭砖－陶瓷怀复合炉底结构,霍戈文式高风温长,寿风炉俄罗斯图拉法渣处理工艺,板壁结合的炉体设备,软水密闭循环冷却水系统等先进技术。