A comparative study of polyurethane and silicone cuffed-catheters in long-term home total parenteral nutrition patients.

AIM: The purpose of this study was to report our compared experience of long-term complications with polyurethane (LeaderCuff) and silicone (Lifevac) tunnelled, cuffed catheters in home adult TPN patients. METHODS: All catheters were inserted by a percutaneous technique under local anaesthesia. RESULTS: Forty silicone catheters were inserted in 31 patients and 13 polyurethane catheters were inserted in 11 patients totaling a total experience of 480 months and 175 months respectively. Mean catheter life span was 12 months (range: 0.25-47) and 13 months (range: 3-44) for Lifevac and LeaderCuff catheters, respectively. Complication rates (expressed as patient-year of TPN) were no significantly different for Lifevac and LeaderCuff catheters: sepsis (0.15 vs 0.14), obstruction (0.05 vs 0), dislodgement (0.13 vs 0.07) and thrombosis (0 vs 0.14). The fracture rate was 20 times lower for Lifevac than for LeaderCuff (P < 0.01): in all cases, this mechanical problem was due to the dysfunction of the detachable flow-control device. CONCLUSION: Both Lifevac and LeaderCuff catheters enable safe, long-term, venous access and prevent, in most cases, inadvertent catheter dislodgement. There is little evidence, from our study, to support the hypothesis that polyurethane catheters offer more security than silicone catheters in home TPN adult patients.     

血管内插管的感染病因

纤维蛋白鞘是血管内插管的感染来源,它通常在中央静脉导管放置3天后形成。但只有大约50％的纤维蛋白鞘培养结果呈阳性。在那些培养结果阳性的病例中,细菌开始繁殖的时间因导管不同部位各不相同：皮下平均5．1天,导管尖端平均8．6天,导管腔内平均13．1天。导管上的细菌越来越多,就越可能发生炎症和血液感染。因导管导致血液感染的危险从小于2／1000器械使用天数（外周静脉留置针,外周穿刺中央静脉导管PICC,隧道式中央静脉导管,皮下输液装置）,10／1000器械使用天数（动脉导管和Swan-Ganz导管）,30－50／1000k器械使用天数（多通路中央静脉导管和肾透析肾插管）。影响血管内插管感染发生的内源性因素包括：宿主情况,细菌类型,导管材料以及制造工艺。人类非常容易感染葡萄球菌,免子却不这样。表面葡萄球菌需要粘多糖才能引起导管感染。硅胶材料的导管比聚氨酯、聚氯乙烯及特氟隆材料更容易发生感染,这可能与它的过度活化作用有关。影响血管内插管感染发生的外源性因素包括：无菌屏障的范围,皮肤消毒剂种类,穿刺人员是否经过专业培训,整个输液系统被外物介入的次数,高营养输液（酵母菌最易繁殖）,5％葡萄糖溶液（革兰氏阴性菌最易繁殖）以及脂质服液（糠疹癣菌最易繁殖）。     

Cuff Cath: an initial experience of cuffed polyurethane central venous catheters in children.

The tendency of medium- and long-term silicone central venous catheters (CVCs) to block, fracture, and become displaced has led to the evaluation of a polyurethane CVC, Cuff Cath (Viggo Spectramed, Swindon, Wilts, United Kingdom) as a possible alternative because polyurethane is smoother and stronger. We report the first prospective study of polyurethane cuffed CVCs in children. Sixty Cuff Caths were placed in 53 children, mean age 4.7 years (range, 4 days to 16.3 years), mean weight 15.6 kg (range, 3.1 to 58 kg). All CVCs were tunnelled (mean tunnel length, 12 cm; range, 5 to 20 cm) and inserted either into the subclavian vein (n = 28) or internal jugular vein (n = 32). In a total of 6363 catheter days (mean, 111 days per patient; range, 15 to 364 days), three (5%) CVCs had to be removed because of sepsis and one (2%) because of blockage. All other Cuff Caths remained patent to infusion and blood sampling. No Cuff Caths were pulled or fell out, fractured, or migrated. This study demonstrates significant advantages of polyurethane compared with previous series using silicone CVCs with respect to blockage, fragmentation, and dislodgement. A prospective, randomized, controlled trial of Cuff Cath compared with a silicone CVCs in children is required.     

Infusion of total parenteral nutrition via the umbilical artery

The administration of total parenteral nutrition through umbilical artery catheters in 48 neonates (birth weight 1.7 +/- 0.58 kg) was compared with administration via central venous catheters in 26 infants (birth weight 2.05 +/- 0.89 kg). There was no significant difference in the amount of calories delivered (72 +/- 12 vs 78 +/- 18 cal/kg/day) or in the mean daily weight gain (16.6 +/- 13.3 vs 18 +/- 13.9 g/day). The incidence of sepsis was significantly lower in the umbilical artery catheter group (10.4% vs 15.4%) but there was no significant difference in the rate of infection when adjustment was made for number of days of catheter life (1 per 224 days of catheter life in the umbilical artery group vs 1 per 199 days in the central venous catheter group). Other major complications included transient hypertension in 2 (4%) of the 48 umbilical artery catheter infants and in 1 (3.8%) of the central venous catheter group, aortic thrombosis in 1 (2%) of the 48 umbilical artery catheter infants and a tricuspid vegetation in 1 (3.8%) of the central venous catheter group. Results suggest that the umbilical artery is a reasonable route for the infusion of total parenteral nutrition in low birth weight infants who require arterial access for blood gas analysis. Use of the umbilical artery catheter for parenteral alimentation may avoid the need for surgical placement of central venous lines and the risk of the attendant complications. Nevertheless, safer routes and improved methods of infusion of parenteral infusion must continue to be developed.     

Evaluation of a percutaneously placed 27-gauge central venous catheter in neonates weighing less than 1200 grams

A percutaneous 27-gauge OD central venous catheter was inserted at 4 +/- 3 (SD) days of age and left in place for up to 2 weeks in 20 neonates with birth weights less than 1200 g and greater than 24 h of age. Parenteral nutritional solutions and medications were administered through these catheters. Twenty neonates matched for birth weight and gestational age served as paired controls. In vitro studies demonstrate that the maximum infusion rate for parenteral nutrition solutions is about 20 ml/hr. Packed red blood cells could not be infused through these catheters. In vivo results demonstrate a significant (p less than 0.05) reduction in number of peripheral iv catheters inserted during study (2 +/- 1 vs 7 +/- 4, SD) with no difference in cost per day of iv access ($79.42 +/- 113.51 vs $43.91 +/- 15.99, SD). Two-dimensional ultrasound assessment of catheter thrombosis was unsuccessful. Moreover, there was no correlation between angiographic and electron microscopic evaluation of catheter tip thrombosis. Electron microscopy of catheter tips revealed 33% with complete, partial and no occlusion, respectively, and 39% with sheath thrombosis. In summary, percutaneous insertion of a 27-gauge OD Vialon central venous catheter is a feasible alternative in providing venous access in very low birth weight infants.     

Environmental Risk Factors for Developing Catheter‐Related Bloodstream Infection in Home Parenteral Nutrition Patients

Background: Tunneled, cuffed, central venous catheters, including Hickman catheters and peripherally inserted central venous catheters (PICCs), are the most commonly used venous access for home parenteral nutrition (HPN) therapy. Catheter‐related bloodstream infection is the most prevalent and severe complication. This study investigated whether environmental risk factors, including smoking, catheter management by a home care nurse, colectomy with stoma, number of infusion days per week, and C‐reactive protein at catheter insertion day, influenced the time to first catheter‐related bloodstream infection (CRBSI). Materials and Methods: In this 6‐year (2008–2014) observational cohort study, adult patients with intestinal failure receiving HPN through either Hickman catheters or PICCs were included. Data were obtained by reviewing medical records, and the environmental risk factors were analyzed with the Cox proportional hazards model. Results: A total of 295 catheters (Hickman catheters: n = 169 and PICCs: n = 126) inserted into 136 patients were registered. Using the PICCs, 1 additional infusion day per week showed to significantly decrease the time to first CRBSI by a factor of 2.47. Hickman catheters managed by a home care nurse had a significantly increased mean (SD) incidence of CRBSI of 1.45 (0.68) per 1000 catheter days. Hickman catheters not managed by a home care nurse had a mean (SD) incidence of 0.56 (0.24). Conclusion: Using the PICC, 1 additional infusion day per week decreased the time to first CRBSI, while having the Hickman catheter managed by a home care nurse increased the mean CRBSI incidence. No other risk factors were found.     

对比两种中心静脉导管的临床应用

目的 对比两种中心静脉导管的置管方法特点及并发症。方法 按时间先后用美国BD公司生产的一次性“经外周静脉置入中心静脉导管”（Peripherally Inserted Central Catheter,简称PICC）或美国Arrow公司生产的双腔或单腔中心静脉导管。观察30天,共80例病人（n=40:40),甲组应用双腔中心锁骨下静脉穿刺至上腔静脉置管,乙组应用PICC导管行经外周静脉置入中心静脉导管。结果 置管成功率：PICC导管置管成功39例占97．5％;锁骨下静脉穿刺成功40例（100％）。导管骨下静脉穿刺导管有1例气胸并发症占2．5％。导管异位,PICC导管有2例占5％;锁骨下天然脉穿刺导管有1例占2．5％。静脉炎发生率,PICC导管有2例占5％;锁骨下静脉穿刺导管无一例静脉炎发生。结论 PICC导管穿刺无风险,部分治疗可取代锁骨下静脉穿刺导管;是抢救危重病人有用的通道。     

Mechanism of thrombogenesis during total parenteral nutrition: role of catheter composition

Catheter material is considered as one of the main factors of deep venous thrombosis during parenteral nutrition. The effects of five types of catheters (polyethylene, polyurethane, silicone, TFE Teflon, and FEP Teflon) on the vein wall and on the blood flow were compared. Experiments were performed on rabbits in which catheters were inserted into the vena cava. Five series of experiments were performed, each including five animals with the same type of catheter. After 10 days, venograms of the vena cava were performed, animals were then killed and the vena cava was removed with the catheter in situ. The vein and the catheter were macroscopically examined; in cases with thrombosis the clot was weighed. The vein wall and the catheter were examined by conventional microscopy and by electron microscopy, respectively. Obstruction of the venous lumen were significantly more frequent with the rigid catheters than with the soft catheters (p less than 0.001). The most extensive thromboses occurred with the Teflon catheters. The incidence of fibrin sleeves was significantly higher with the soft catheters than with the rigid ones (p less than 0.01). The venographic and macroscopic findings were in agreement in 60-100% of the cases according to the degree of venous obstruction. Catheter surfaces remained unchanged in all cases. The polyethylene catheters induced the most severe intimal inflammatory reactions. Thrombus formation was caused by two mechanisms depending on catheter composition: (1) turbulence caused by the catheter in the blood stream, and (2) platelet aggregation and subsequently, fibrin deposition on the surface of the catheter.     

Duplex Doppler ultrasound identifies veins suitable for insertion of central feeding catheters.

Central venous access for feeding catheters may prove difficult in patients who have had numerous previous central line insertions or complications. Duplex Doppler ultrasound was used to identify the anatomy and patency of major central veins in 11 patients in whom attempts at obtaining central venous access by an experienced operator had failed at least once and in 40 control subjects. Doppler ultrasound demonstrated the subclavian veins (diameter 12.5 +/- 3.5 mm, mean +/- SE) and internal jugular veins (11 +/- 3.5 mm) in all the control subjects. In the patients, 18 of 44 veins were patent, 11 were small or had low blood flow, and 15 were thrombosed. In 7 patients who required central feeding catheter insertion, a suitable vein was identified and the catheter suitably placed, even in 3 subjects where no central vein was considered normal. Duplex Doppler ultrasonography is a useful technique for identifying veins suitable for the insertion of central venous lines when access has previously proved difficult.     

Central venous thrombosis related to the silastic Hickman-Broviac catheter in an oncologic population

The use of subcutaneously implanted, Dacron cuffed, central venous silastic catheters (Hickman/Broviac catheter [HC/BC]) has not eliminated catheter related-central venous thrombosis (CR-CVT). HC/BC related CR-CVT was identified and followed in 15 oncology patients. Median time period to CR-CVT was 155 days (range 15-638). No correlation was established to patient age, sex, diagnosis, coagulation status, use, longevity, technique, or site of placement. Fourteen patients were treated with anticoagulation and/or thrombolytic therapy. Of seven patients treated with HC/BC in situ, one required HC/BC removal to achieve CR-CVT resolution. Median follow-up post-CR-CVT was 362 days (range 34-1622). No patient suffered untoward long-term sequelae. Nine patients had 11 catheters placed following resolution of CR-CVT. None had repeat thrombosis. CR-CVT incidence in a single 12-month period was 3.7% (7/190). The placement of HC/BC in an oncology population is an acceptably safe method for long-term venous access.     

A cuffed polyurethane catheter for long-term central venous access: a novel technique prevents early displacement

A new method which provides immediate fixation of a cuffed central venous catheter is described. The cuffed polyurethane catheter has a detachable hub which allows the creation of a second small tunnel distal to the cuff using the wire and the vein dilator. As the catheter exits from a "pinhole," immediate fixation is assured and is independent of tissue healing.     

Fine bore silicone rubber and polyurethane catheters for the delivery of complete intravenous nutrition via a peripheral vein

The aim of the study was to evaluate two fine bore catheters for the delivery of complete intravenous nutrition (IVN), of osmolality 1250 mosm/kg, via a peripheral vein. 50 patients were randomised to receive either a 23G silicone rubber catheter or 22G polyurethane catheter. The median duration of feeding was 9 days for silicone rubber catheters and 10 days for polyurethane catheters. Silicone rubber catheters developed complications significantly more frequently (44%) than polyurethane catheters (22%, p < 0.05). There was no significant difference in the median life span of the catheters removed because of complications, nor in the daily risk of thrombophlebitis. 92% of patients who were fed through a polyurethane catheter required only a single catheter for the duration of IVN. The peripheral venous route should be the first choice when the administration of IVN is considered for a period of less than 2 weeks.     

Material thrombogenicity in central venous catheterization: a comparison between soft, antebrachial catheters of silicone elastomer and polyurethane

In order to compare two types of long, soft central venous catheters with the same stiffness, 39 silicone elastomer (SE) and 36 polyurethane (PU) catheters were inserted in 75 patients via basilic or cephalic veins punctured at the cubital fossa. Mean duration of catheterization was 10.5 days. Scanning electron microscopy revealed that the SE catheters to have a more uniform, but somewhat rougher surface topography than the PU catheters. The platelet adhesion in vitro to the SE catheters was four times higher than to the PU catheters. The incidence of clinical thrombophlebitis in the arm veins was 36% with the SE catheters, and 5.5% with the PU catheters (p less than 0.01). No significant differences were found between the SE and PU catheters regarding the number and size of radiologic thrombi in the peripheral and central veins, catheter occlusion rate, and platelet adhesion to the inner side of the catheter tip at withdrawal. Platelet adhesion in vivo correlated with the duration of catheterization in both groups of catheters. Mechanical trauma to the vein endothelium seems to be of vital importance in thrombus formation, but not in the induction of clinical thrombophlebitis.     

Complications and cost associated with parenteral nutrition delivered to hospitalized patients through either subclavian or peripherally-inserted central catheters

BACKGROUND AND AIMS: Total parenteral nutrition (TPN) is typically delivered through catheters inserted into the superior vena cava (SVC) via a subclavian or internal jugular vein approach. A peripherally-inserted central venous catheter (PICC), utilizing a cephalic or basilic venous approach, may provide a safe alternative to the standard catheter approach and, because non-physician providers can insert the PICC, may introduce a potential cost-savings to health care institutions. We sought to determine if PICC lines are safer and more cost-effective than the standard central venous catheter approach for hospitalized patients who require TPN. METHODS: One hundred and two hospitalized patients (age range, 18-88 years) who required TPN were prospectively randomized to receive therapy via a centrally-inserted subclavian catheter (n=51) or a peripherally-inserted PICC line (n=51). The primary end-point was the development of a complication requiring catheter removal. Other end-points included catheter infection and thrombophlebitis. Cost associated with insertion and maintenance of each catheter was also studied. RESULTS: Complication-free delivery rate (without the need to remove or replace the catheter) was 67% for subclavian catheters and 46% for PICC lines (P<0.05). The overall infection rate was 4.9 per 1000 catheter days and was similar for each catheter type (P=0.68). PICC lines were associated with higher rates of clinically-evident thrombophlebitis (P<0.01), difficult insertion attempts (P<0.05), and malposition on insertion (P<0.05). No catheter complications resulted in significant long-term morbity or mortality. No significant difference was noted between the two catheter types in terms of aborted insertion attempts (P=0.18), dislodgement (P=0.12), or line occlusion (P=0.25). After standardizing costs for each hospital, the direct institutional costs for insertion and maintenance of PICC lines (US$22.32+/-2.74 per day) was greater than that for subclavian lines (US$16.20+/-2.96 per day;P<0.05). CONCLUSION: PICC catheters have higher thrombophlebitis rates and are more difficult to insert into certain patients when compared to the standard subclavian approach for central venous access in hospitalized patients who require TPN. Because of this, PICCs may be less cost-effective than currently believed because of the difficulty in inserting and maintaining the catheter.     

Percutaneous and surgical placement of fine silicone elastomer central catheters in high-risk newborns

Percutaneous insertion of fine silicone elastomer catheters (0.6 millimeters outside diameter) have been used for central parenteral nutrition of very low birth weight and other high risk infants. Because peripheral venous access can be limited in the newborn, we report the previously undescribed surgical cannulation of the superficial arm veins with this catheter, and compare our experience with this technique and the percutaneous method in neonates. A central catheter position was attained in 88% of surgical (38 of 43) and 74% of percutaneous (17 of 23) cannulations. The two groups did not differ in birth weight or gestational age. The mean duration of catheterization was similar in the two groups (combined means = 21.8 +/- 2.3 days SEM). There was no difference in weight gain (combined means = 16.9 +/- 1.0 grams SEM per day) or head growth (combined means = 1.1 +/- 0.1 millimeters per day) between the groups and these rates approximated known fetal growth rates for our mean gestational age. Disseminated candidiasis, in a 770-gram infant with thymic hypoplasia, caused the only systemic infection and death among our 49 patients. The most commonly encountered problem was catheter occlusion secondary to a blood clot at the tip of these fine catheters (8 of 55). No thromboembolic events were recognized, and minor complications were not different with the two techniques. Surgical cannulation of the superficial arm veins offers a safe alternative to percutaneous central silicone elastomer catheter placement if superficial venous access is not available. Both methods provided early, adequate parenteral nutrition without excessive fluid intake in our high-risk infants, and undoubtedly contributed to a favorable neonatal outcome.     

Long term parenteral therapy by percutaneous tunneled silicone central venous catheter--a follow-up of 300 catheters

We have developed a technique for the management of central venous catheters which incorporates percutaneous insertion and daily care for routine use in different wards. A follow-up of the first 300 catheters is presented. When intravenous therapy was planned for more than two weeks, a silicone rubber catheter was introduced percutaneously with a skin tunnel and the position of the tip in the lower superior vena cava checked by venous pressure measurement. The metal hub of the catheter was disinfected daily by heating with a modified soldering iron which has been proved to be effective by in vitro testing with different microorganisms. The external jugular vein was used in 164 cases (55 per cent) the internal jugular vein in 115 (38 per cent) and the remaining catheters were inserted by the subclavian or antecubital route. Correct positioning was obtained in 96 per cent and serious early or late complications were rare there being only one case of septicaemia in a total treatment period of 270 months. One patient developed a lung infarct, but no case of pneumothorax has been seen. The mean duration of the catheters was 27 days (range 1-239) and the common reasons for termination were cessation of need in 84 per cent, mechanical obstruction in 6 per cent and inadvertent removal in 6 per cent. The described method has proved to be safe and to function well on ordinary wards.     

Effect of a betadine connection shield on central venous catheter sepsis.

The effect on the rate of central venous catheter sepsis of incorporating the catheter hub in a povidone-iodine (Betadine) connection shield was evaluated in a randomized controlled clinical trial involving 47 Silastic catheters inserted in 35 patients solely for the administration of parenteral nutrition. All catheters were tunneled subcutaneously and once inserted were randomized to one of two subsequent management groups. Group 1 (n = 25) were managed in a standard fashion whereas Group 2 catheters (n = 22) in addition were managed by incorporating the catheter hub in a Betadine connection shield (Connection Shield 3; Travenol/Baxter). The catheter lifespans in the two groups were similar (Group 1 mean 10.8 days; range 3-28: Group 2 mean 13.3 days: range 5-31). There was a significant difference in the rates of both clinical sepsis (Group 1, 8 cases; 32%; Group 2, 1 case; 4.5%; p less than 0.05) and bacteriologic sepsis (Group 1, 6 cases; 24%; Group 2, 0 cases; p less than 0.05) in the two groups. Incorporating the catheter hub in a Betadine connection shield confers significant benefit in terms of reducing the incidence of catheter sepsis in patients receiving total parenteral nutrition.     

Mechanisms and risk factors for infection of pulmonary artery catheters and introducer sheaths in cancer patients admitted toan intensive care unit

Pulmonary artery catheters (PACs) are typically inserted for short periods, and the extra-luminal route is assumed to be the overriding source of contamination and/or infection. Our aim was to assess the incidence of PAC and introducer colonization in cancer patients, and to study the mechanisms and risk factors for infection. Patients with a Swan-Ganz catheter admitted to an intensive care unit were prospectively analyzed over 14 months. As soon they were no longer necessary, PACs and introducer sheaths were removed and cultured. We recorded the mean duration of placement, the number of times PACs were handled and the site of insertion. Seventy-nine catheters were inserted in 68 patients. The median (range) duration was three days (0-10) for PACs, and 3.6 days (0-18) for introducers. PAC and/or percutaneous introducer sheath colonization was diagnosed in seven patients (8.9%), but in only one case were both colonized. Colonization rates were 15.5 per 1000 days for PACs and 14.1 per 1000 days for introducers. Introducers were mainly colonized before the 5th day, while PACs were mainly colonized after the 5th day. No PAC or introducer-related local infection or bacteraemia was diagnosed. Colonization was more frequent on catheters inserted into the internal jugular vein. The colonization rate was 5% for PACs and introducers. Our findings suggest that contamination of introducers and PACs may be dissociated and could result from either extraluminal or endoluminal colonization. As three of four PAC colonizations occurred after 5 days, the duration of catheter placement should be considered important. There was little clinical impact of microbial colonization.     

Care of the central venous catheterization site: the use of a transparent polyurethane film

Studies of care of patients with central venous catheters report a 3-7% incidence of catheter-induced sepsis when sterile gauze and tape are used as an occlusive dressing. The technique requires that the dressing be changed three times each week for catheterization site inspection. From June 1979 to September 1980, a noncomparative evaluation of a transparent, self-adhesive, polyurethane dressing which is permeable to water vapor but not bacteria was performed. This dressing was used for the care of 100 consecutive patients with central venous catheters. Dressing life averaged 5.3 days with silicone rubber catheters and 4.3 days for polyvinyl chloride catheters. One patient developed catheter induced sepsis (incidence 1%). This dressing material: (1) is acceptable for use as a dressing of central venous catheters; (2) continuously permits inspection of the insertion sites; (3) decreases nursing hours; (4) provides a comfortable dressing which secures the catheter to the patient; and (5) is durable even when exposed to high humidity therapy devices, or when possible permits the patient to take showers.     

Partial peritoneal alimentation in an infant

We provided partial peritoneal alimentation to a 1.69-kg 11-month-old premature infant who had no available central venous access, depleted peripheral venous access, and gastrointestinal dysfunction. A cuffed silastic catheter was surgically inserted into the suprahepatic space. An alimentation solution was continuously infused into the peritoneum for 28 days to supplement peripheral venous and nasogastric alimentation and contributed 42 +/- 15% of total calories daily. Weight gain was achieved, but complications included hypoglycemia, hypophosphatemia, intravascular dehydration, catheter site leakage, ascites, and hydrocele. At autopsy 11 months later, lipid accumulation was present in the upper peritoneum and the hilar regions of the lungs secondary to preexisting lymphatic obstruction. Partial peritoneal alimentation may be feasible when other access routes are inadequate, but lymphatic obstruction is a contraindication to the peritoneal administration of lipid emulsions.