Spontaneous pulmonary air embolism in a child undergoing procedural deep sedation: case report and review of the literature

We performed a systematic review of the literature starting from a real case of venous air embolism (VAE) in a young infant undergoing central catheterization during procedural sedation. Air embolism due to internal jugular vein catheterization during procedural sedation is very rare, but it is a potentially life-threatening complication of central catheterization that warrants attention. To our knowledge, this is the first case published in a similar scenario.

Percutaneous Intravascular Retrieval of Embolised Fragments of Long-Term Central Venous Catheters

Embolisation of a catheter fragment is a rare mechanical complication of long-term central venous access devices. From 1995 to 1999 we observed 10 cases: the cause of embolisation was the ‘pinch-off syndrome’ in half of the cases, and in 8 cases out of 10 the fragment had embolised in the pulmonary arterial vessels. Percutaneous transvenous retrieval was successful in all cases; it was performed mainly (8 cases out of ten) through the left transfemoral route, using a single-snare-loop device sometimes associated with a pig-tail catheter. We had no mortality and no major complications. On the basis of our experience, we believe that catheter embolisation of long-term central venous devices can be effectively prevented by adequate insertion technique, proper management of the device during its clinical use, and accurate removal technique. Nonetheless, should catheter embolistion occur, the patient should be referred to a Centre with adequate experience in the field of interventional radiological techniques. Should the radiological retrieval procedure fail, evidence from the literature suggests that leaving the fragment in embolisation site might be safer than open extraction by surgical thoracotomy, particularly in oncological patients with reduced life expectancy.

Which is the Easiest and Safest Technique for Central venous Access? A Retrospective Survey of more than 5,400 Cases

There is an ongoing debate on the technique for central venous catheterization associated with the lowest complication rate and the highest success rate. In an attempt to better define the easiest and safest venous approach, we have reviewed our 7-year experience with 5479 central venous percutaneous punctures (by Seldinger's technique) for the insertion of short-term (n=2109), medium/long-term (n=2627) catheters, as well as double-lumen, large-bore catheters for hemodialysis and/or hemapheresis (n=743). We have analyzed the incidence of the most frequent insertion-related complications by comparing seven different venous approaches: jugular vein, low lateral approach; jugular vein, high lateral approach; jugular vein, low axial approach; subclavian vein, infraclavicular approach; subclavian vein, supraclavicular approach; external jugular vein; femoral vein.

The results of our retrospective study suggest that the ‘low lateral’ approach to the internal jugular vein, as described by Jernigan and modified according to our protocol, appears to be the easiest and safest technique for percutaneous insertion of central venous access, being characterized by the lowest incidence of accidental arterial puncture (1.2%) and malposition (0.8%), no pneumothorax, and an extremely low rate of repeated attempts (i.e. more than two punctures before successful cannulation) (3.3%). We advocate the ‘low lateral’ approach to the internal jugular vein as first-choice technique for venipuncture in both adults and children, for both short-term and long-term central venous percutaneous cannulation.

Valved Central Venous Catheter Connected to Subcutaneous Port: A Multicenter Phase IV Study Based on a Cohort of 50 Oncology Patients

Purpose

Since technical aspects and clinical features of central venous valved catheters are far from being completely understood, a multinational group of investigators has decided to assess a new distally-valved catheter connected to a port, in the clinical setting of oncology patients undergoing chemotherapy, in an attempt to verify its safety and viability, while also investigating its practical features.

Methods

Our project was structured as a phase IV multicenter study. Hospitalized adults (ages 18–80 years) who had solid tumors and were candidate for intravenous chemotherapy met the criteria to enter the study. One single type of port was used (made of titanium, plastic and silicone) connected to a silicone, distally valved catheter (as manufactured by B. Braun Aesculap). A case report form was provided for each treated case; all relevant data regarding implantation and follow-up were entered into the form, mailed to a coordinating center (G. Chevillon, B. Braun Medical, France) and stored in a software database for statistical analysis.

Results

50 patients (from 6 participating centers) were included in this study. No major complications occurred at insertion. The most frequent clinical problem during follow-up was inability to draw blood samples (9% during the first chemotherapy cycle; 8% after the second cycle); blood obtained from the device was defined “unsuitable for hematology test” in 9% of the cases at first chemotherapy cycle and in 23% of the cases after the second cycle. No catheter obstruction occurred.

Conclusion

The distally valved catheter port tested in this study was reliable, safe and practical for long-term treatment of an oncology patients’ population undergoing chemotherapy. As most other reports and clinical trials dealing with other types of distally valved catheters pointed out, inability to draw viable blood samples (so called withdrawal occlusion) is a major concern in their clinical use. Mechanisms underlying this technical problem are still unclear.

Preventing hospital malnutrition: a survey on nutritional policies in an Italian University Hospital

BACKGROUND

A proper strategy for fighting hospital malnutrition should include nutritional screening of all hospitalized patients, adequate utilization of the Hospital facilities - such as Clinical Nutrition Services or Nutrition Teams - and an adequate algorithm for the adoption of proper nutrition support (oral, enteral or parenteral) with proper timing. The main aim of the present study was to investigate the current policies of different non-intensive wards of our institution (a 1100 beds University Hospital) in terms of prevention of hospital malnutrition.

METHODS

We conducted a one-day survey to verify the current policies of nutritional screening and the indication to nutritional support in adult patients, interviewing nurses and physicians of our non-intensive hospital wards.

RESULTS

A total of 29 wards were considered, which sum up to 755 hospitalized patients. We found that nutritional screening at admission is routinely assessed only in 41% of wards and that oral nutrient intake is controlled regularly only in 72%. Indication to clinical nutrition support and specifically to artificial nutrition is not consistent with the current international guidelines. Only 14% of patients were receiving artificial nutrition at the moment of the survey and the majority of them were given parenteral nutrition rather than enteral feeding.

CONCLUSION

Our survey confirmed that in large hospitals the main barriers to the fight against hospital malnutrition are the lack of knowledge and/or commitment by nurses and physicians as well as the lack of well-defined hospital policies on early nutritional screening, surveillance of nutritional status and indication to nutrition support.

Evidence-based consensus on the insertion of central venous access devices: definition of minimal requirements for training

There is a lack of standard minimal requirements for the training of insertion techniques and maintenance of central venous access devices (CVADs). An international evidence-based consensus task force was established through the World Congress of Vascular Access (WoCoVA) to provide definitions and recommendations for training and insertion of CVADs. Medical literature published from February 1971 to April 2012 regarding 'central vascular access', 'training', 'competency', 'simulation', and 'ultrasound' was reviewed on Pubmed, BioMed Central, ScienceDirect, and Scopus databases. The GRADE and the GRADE-RAND methods were utilized to develop recommendations. Out of 156 papers initially identified, 83 papers described training for central vascular access placement. Sixteen recommendations are proposed by this task force, each with an evidence level, degree of consensus, and recommendation grade. These recommendations suggest central venous access education include didactic or web-based teaching with insertion procedure, infection prevention, complications, care, and maintenance of devices, along with laboratory models and tools for simulation practice incorporating ultrasound. Clinical competence should be determined by observation during clinical practice using a global rating scale rather than by the number of procedures performed. Ensuring safe insertion and management of central venous devices requires standardized education, simulation practice, and supervised insertions.

Non-tunneled central venous catheters in adult stem cell transplantation recipients: An effective option

Stem cell transplantation (SCT) recipients require central venous catheter (CVC) insertion for the administration of chemotherapy, antibiotics and total parenteral nutrition. Traditionally, tunneled CVC have been considered as the golden standard although they require surgery for both insertion and removal. We prospectively evaluated the use of a non-tunneled CVC in 182 consecutive patients who had undergone allogenic or autologous SCT. The median duration of CVC was 4 weeks (range 1-24) with a significant difference between allogenic (8 weeks, range 2-24) and autologous SCT (4 weeks, range 1-24) (p<0.0001). The life expectancy of the CVC was significantly influenced by spontaneous removal, which occurred in 26 patients (13.8%). There was a significant increase of this complication in allogenic SCT (p=0.039). The overall incidence of sepsis was 24.5%, although catheter-related sepsis was microbiologically documented by positive culture of the tip only in 17 cases (9%). Non-tunneled CVC in adult SCT recipients allowed (a) bedside insertion and removal, (b) guidewire replacement for diagnostic or therapeutic purposes (dialysis or pheresis procedures) thus reducing the need for repeated venipunctures. (The Journal of Vascular Access 2001; 2: 168-174).

Old and new tools in the diagnosis of central venous catheter-related bloodstream infections: is there a role for brushing?

Bloodstream infections (BSIs) are the third most common nosocomial infections. Catheters and other medical devices are the first exogenous causes of preventable infections in hospital. The estimated attributable mortality for catheter-associated BSI ranges from 1-35%, mainly depending on etiological agents and underlying disease. In considering this, it is necessary to reduce central venous catheter- (CVC)-related BSI prevalence and to obtain a rapid and accurate method for an early diagnosis. This review indicates the advantages and the disadvantages of old and new tools for the early diagnosis of CVC-related BSIs.

[Central venous catheter-related sepsis: one year experience in a large university hospital]

Five hundred two central venous catheters (CVC) inserted in 366 patients were evaluated prospectively over a one-year period to determine the frequency and risk factors associated with CVC-related sepsis. A CVC-related infection was suspected in 190 cases (190/502, 38%). A catheter-related sepsis was established in 50 patients (10%). The infection rate was 0.8 cases of sepsis per 100 catheterdays. Staphylococcus epidermidis, Staphylococcus aureus, and Candida spp. were the most frequently isolated etiological agents of sepsis. On univariate analysis, six variables affecting the rate of catheter-related sepsis were identified: neutropenia > 8 days (p < 0.01); AIDS (p < 0.001); haematological malignancies (p < 0.001); total parenteral nutrition (p = 0.001); duration of site use (p = 0.04); high APACHE II score (p = 0.04). The logistic regression analysis revealed that AIDS and haematological malignancies were independent risk factors of catheter-related sepsis. In conclusion, although the incidence of established catheter infection is much lower than the incidence of suspected infection, in most cases it is wise to change the catheter with the guidewire technique and wait for culture of the tip, rather than to remove the catheter immediately.

[Central venous catheterization: complications of different placements]

STUDY AIM

The aim of this prospective multicentric non-randomised trial was to report the complications of the central venous catheter insertion with different techniques and to assess the advantages of the low lateral approach to the internal jugular vein, according to the technique originally described by Jernigan et al, with our own modifications.

PATIENTS AND METHOD

From January 1993 to August 1997, 2,290 CVC (2,286 by percutaneous puncture and 4 by surgical approach) were placed. The following complications were analysed prospectively: pneumothorax, accidental arterial puncture, more than two punctures of the same vein, necessity to shift to another venous approach, complete failure, malposition of catheter.

RESULTS

The veins the most frequently used were internal jugular vein (48.7%), femoral vein (27%) and subclavian vein (24.2%). Internal jugular vein was punctured especially by low lateral approach (75%) and subclavian vein by infraclavicular approach (92%). With these two placements, the rate of pneumothorax was 0% and 3.1% respectively (p < 0.001), the rate of accidental arterial puncture was 1% and 2.7% respectively (p < 0.03) and the rate of more than two consecutive punctures was 3.1% and 6.3% respectively (p < 0.008).

CONCLUSION

On our experience, we advocate the low lateral approach to the internal jugular vein as first choice technique for venipuncture in both adults and children for both short and long-term central venous approach, because it is associated to high rate of outcome and to low rate of complications in comparison with other techniques.

Morbidity associated with central venous catheter-use in a cohort of 212 hospitalized subjects with HIV infection

Technical complications and nosocomial bloodstream infections associated with short-term central venous catheterization remain a heavy burden in terms of morbidity, mortality and cost in HIV-positive subjects. Between 1994 and 1997, 327 central venous catheters (CVCs) inserted in 212 patients for a total of 5005 catheter days were investigated. Forty-two technical complications (13%) occurred in 40 patients. Logistic regression analysis revealed that a high APACHE III score was associated with development of CVC-related complications (P = 0.01). One hundred and eight of 327 CVCs (33%) were suspected as being infected. However only 61 episodes (61/327, 19%) were finally diagnosed as CVC-related sepsis. Three variables affecting the rate of CVC-related sepsis were identified: 1) administration of TPN (P = 0.01); 2) low number of circulating CD4+ cells (P = 0.04); 3) high APACHE III score (P = 0. 04). Doctors responsible for AIDS patients should carefully consider the relative risks and benefits of CVC insertion in an individual patient.

The Hohn catheter in the management of haemopoietic stem cell transplant recipients

Patients undergoing bone marrow transplantation require a reliable venous access. The authors have tested the feasibility and safety of a new, silicone, open-ended, non-tunnelled central venous catheter (CVC), the Hohn catheter (Bard Access System, USA). From January 1994 to December 1996, 58 Hohn were inserted into 56 bone marrow transplant (BMT) patients (26 women: 30 men; mean age 38 years, range 19-62 years). The CVC was inserted percutaneously at the bedside by puncture of the subclavian or the internal jugular vein. No early complications were observed. Significant late complications were infection (documented only in 14%) and accidental removal (11%). The median life of the CVC was 30 days (range 15-180 days). Major causes of removal were end of use (25 patients) and fever (19 patients; but infection was documented only in eight patients). In spite of the relatively small gauge (5 Fr), the Hohn catheter was adequate for rapid or high density infusion. In our experience, the unique features of the Hohn CVC (versatility, optimal biocompatibility, bedside management, low cost) may contribute to making the BMT procedure safer and less expensive.

Pregnancy outcome and total parenteral nutrition in malnourished pregnant women

OBJECTIVE

We evaluated pregnancy outcome and fetal growth in women requiring total parenteral nutrition (TPN).

METHODS

Eleven malnourished pregnant women were treated with TPN in a single institution, starting at a mean gestational age of 20+/-8 weeks (+/- SD). Serial ultrasound evaluations of fetal growth (biparietal diameter, femur length, abdominal circumference) were performed. The paired Student t test and Wilcoxon signed-rank test were used for the statistical analysis: p values <0.05 were considered significant.

RESULTS

The duration of TPN ranged from 14 to 220 days. Maternal nutritional state was well preserved and no complications were related to treatment. A gestational age of 35+/-3 weeks at delivery (mean +/- SD), birth weight of 2,251+/-670 g (mean +/- SD) and birth percentile of 29+/-16 (mean +/- SD) were observed. One intrauterine death occurred. The comparison between the sonographic findings, before and 2 weeks after starting TPN, showed a fetal percentile gain with a statistically significant increase in the abdominal circumference percentile (p < 0.05) from a median percentile of 2 (range 2-32) to 33 (range 2-78).

CONCLUSIONS

TPN proved to be helpful and lifesaving in malnourished pregnant women and promoted fetal growth, as shown by the longitudinal ultrasonographic evaluations.

Tension-free hernioplasty: technical remarks and personal experience

The authors report their experience with 463 tension free hernioplasty procedures for inguinal and femoral hernias. The surgical technique included the insertion of both a polypropylene plug and a polypropylene mesh, and was carried out mostly in local anesthesia (84.2%) using bupivacaine 0.25% for ileoinguinal and ileohypogastric blockage and mepivacaine 0.5% for local infiltration. There was no major intraoperative complication; local postoperative complications were rare (10%) and easily managed; postoperative pain was frequently observed (66%), though mild and transient; resumption of working activity occurred within a month in 96.6% of cases; there were only 3 post-operative recurrences (respectively, at 1, 6 and 12 months). The authors conclude that the tension free hernioplasty is a simple, rapid, low-cost and effective technique, easily performed under local anesthesia.

Central venous catheter-related sepsis in a cohort of 366 hospitalised patients

Five hundred two central venous catheters inserted in 366 patients were evaluated prospectively over a one-year period to determine the frequency and risk factors associated with catheter-related sepsis. For study purposes, in cases in which catheter infection was suspected but the initial blood cultures were negative, the catheters were replaced by guidewire technique; otherwise, the catheters were routinely changed after 21 days by guidewire technique. A catheter-related infection was suspected in 190 cases (190/502, 38%). A diagnosis of catheter-related sepsis was established in 50 patients, which represents 10% of the total number of lines (502). Over a total of 6428 days of catheter use, the infection rate was 0.8 cases of sepsis per 100 catheter-days. Staphylococcus epidermidis, Staphylococcus aureus, and Candida spp. were the most frequently isolated aetiological agents of sepsis. On univariate analysis, six variables affecting the rate of catheter-related sepsis were identified: neutropenia for more than eight days (p < 0.001); AIDS (p < 0.001); haematological malignancy (p < 0.001); administration of total parenteral nutrition (p = 0.001); duration of site use (p = 0.04); and high APACHE II score (p = 0.04). The logistic regression analysis revealed that AIDS and haematological malignancies were independent risk factors of catheter-related sepsis. Catheter replacement over a guidewire was no more likely to be associated with sepsis than was percutaneous catheter insertion. In conclusion, although the incidence of established catheter infection is much lower than the incidence of suspected infection, in most cases of suspected infection it is wise to change the catheter with the guidewire technique and wait for culture of the tip, rather than to remove the catheter immediately. Such a policy may help reduce the number of unnecessary catheter removals.

Determinants of urea nitrogen production in sepsis. Muscle catabolism, total parenteral nutrition, and hepatic clearance of amino acids

The major determinants of urea production were investigated in 26 patients with multiple trauma (300 studies). The body clearances (CLRs) of ten amino acids (AAs) were estimated as a ratio of muscle-released AAs plus total parenteral nutrition-infused AAs to their extracellular pool. While clinically septic trauma (ST) patients without multiple-organ failure syndrome (MOFS) had a higher level of urea nitrogen production (25.6 +/- 13.4 g of N per day) compared with nonseptic trauma (NST) patients (14 +/- 7.5 g of N per day) and with ST patients with MOFS (4.28 +/- 1.5 g of N per day), in all groups urea N production was found to be a function of muscle protein degradation (catabolism), total parenteral nutrition-administered AAs, and the ratio between leucine CLR and tyrosine CLR (L/T) (r2 = .82, P less than .0001). Since tyrosine is cleared almost exclusively by the liver, the L/T ratio may be regarded as an index of hepatic function. The significant differences between urea N production in ST and NST patients lay in an increased positive dependence on muscle catabolism and increased negative correlation with L/T in the ST group. At any L/T ratio, urea N production was increased in ST patients over NST patients, but in ST patients with MOFS, it fell to or below levels of NST patients. These data show that the ST process is associated with enhancement of ureagenesis, due to increased hepatic CLR of both exogenous and endogenous AAs. In sepsis with MOFS, a marked inhibition of urea synthesis occurs, partially explained by a decreased hepatic CLR of non-branched-chain AAs.

Increased dependence of leucine in posttraumatic sepsis: leucine/tyrosine clearance ratio as an indicator of hepatic impairment in septic multiple organ failure syndrome

The body clearance of 10 plasma amino acids (AA) was determined from the rate of compared muscle-released AA and AA administered by infusion of total parenteral nutrition (TPN) compared to their estimated extracellular (ECW) pool in patients with multiple trauma with (n = 10) or without (n = 16) sepsis at 8-hour intervals. In both nonseptic and septic trauma, increasing TPN increased the mean clearance rate of all infused AA. When the individual AA clearance rates were normalized by the total AA infusion rate, regression-covariance analysis revealed that patients with sepsis had relatively impaired clearances of alanine (p less than 0.01) and methionine, proline, phenylalanine, and tyrosine p less than 0.05 for all). In contrast, the clearances of branched-chain AA (BCAA) valine and isoleucine were maintained, and the clearance of leucine was higher (p less than 0.05) in trauma patients with sepsis than in those without. At any AA infusion rate, compared with surviving patients with sepsis (p less than 0.05), patients who developed fatal multiple organ failure syndrome (MOFS) showed increased clearances of all BCAA with further impaired clearance of tyrosine. The clearance ratio of leucine/tyrosine was increased in MOFS at any AA infusion rate (p less than 0.0001), was an indicator of severity, and, if persistent, was a manifestation of a fatal outcome. Because tyrosine metabolism occurs almost entirely in the liver while leucine can be utilized by viscera and muscle, these data suggest early and progressive septic impairment of the pattern of hepatic uptake and oxidation of AA with a greater body dependence on BCAA, especially leucine, as septic MOFS develops.

Plasma carnitine levels and urinary carnitine excretion during sepsis

Carnitine is an indispensable factor for the beta-oxidation of medium- and long-chain fatty acids, and it plays a possible role in the oxidation of branched-chain amino acids. Plasma and urinary levels of free carnitine and short-chain acyl-carnitines were studied in 67 surgical patients, after non-septic surgical procedures or during sepsis. The septic state was associated with increased urinary excretion of free carnitine (p less than 0.001), as well as with lower plasma levels of short-chain acyl-carnitines (p less than 0.001); the latter feature correlated with the level of hypermetabolism, as evaluated by the metabolic rate and by the arterial-mixed venous O2 difference. In 26 patients during total parenteral nutrition D, L-acetyl-carnitine was administered (100 mg/kg/24 hrs, in continuous iv infusion) and was associated, in septic patients only, with a significant decrease in the respiratory quotient, suggesting enhanced oxidation of low respiratory quotient substrates (fatty acids and/or branched-chain amino acids). Carnitine supplementation during total parenteral nutrition might be of theoretical benefit in some clinical conditions, such as sepsis, in which the following conditions coexist enhanced utilization of substrates whose oxidation is partially or totally carnitine dependent; prolonged absence of exogenous intake of carnitine (as in long-term total parenteral nutrition); eventual impairment of carnitine synthesis due to hepatic dysfunction; increased, massive urinary loss of carnitine.

Respiratory quotient and patterns of substrate utilization in human sepsis and trauma

Three hundred measurements of indirect calorimetric and hemodynamic variables were performed in 99 critically ill septic and nonseptic surgical patients. Septics manifested, with respect to nonseptics, higher O2 consumption, metabolic rate and cardiac index, and lower respiratory quotient in the presence of higher glucose infusion rates and glucose infusion rate/metabolic rate ratios. Among septics there was a group of more severely ill patients with signs of multiple organ failure who manifested a dissociated pattern characterized by a tendency to decreased O2 consumption in the presence of increasing cardiac index and central venous O2 partial pressure: they had higher respiratory quotients, with respect to the other septics, for a given glucose infusion rate/metabolic rate ratio. The lower mean respiratory quotient of septics indicates that they depend generally more than nonseptic trauma patients on fat as an energy substrate and confirms a previously obtained evidence of limited hepatic lipogenesis in sepsis. At the same time, however, it is suggested that fat utilization becomes impaired (and hepatic lipogenesis becomes prominent) in sepsis at a stage in which signs of impaired oxidative metabolism and major metabolic abnormalities also develop.

Preoperative treatment of hydatid cysts with mebendazole

Mebendazole--an anthelmintic drug which is known to have a lethal effect on hydatid cysts--was administered preoperatively to patients affected by Echinococciasis, in order to sterilize cysts and prevent surgical contamination. Our results suggest that mebendazole treatment (1500 mg/die for 25 days) was effective in ten out of eleven cases; no major toxic effect was observed.

[Segmental transplant of the pancreas in the pig with suppression of the exocrine secretion. Technical aspects]

Twenty autotransplantations and five allotransplantations were performed in female pigs; exocrine secretion was suppressed by injecting an acrylic glue into the ductal system; pancreatic segment was transplanted extraperitoneally in the iliac fussa. We describe an original technique most suitable to the morfologic caratheristics of pancreatic gland in pigs.