2008 SOR guidelines for the prevention and treatment of thrombosis associated with central venous catheters in patients with cancer: report from the working group.

BACKGROUND: In view of the lack of recommendations on central venous catheter (CVC)-associated thrombosis in cancer patients, we established guidelines according to the well-standardized Standards, Options and Recommendations methodology. MATERIAL AND METHODS: A literature review (1990-2007) on CVC-associated thrombosis was carried out. The guidelines were developed on the basis of the corresponding levels of evidence derived from analysis of the 36 of 175 publications selected. They were then peer reviewed by 65 independent experts. RESULTS: For the prevention of CVC-associated thrombosis, the distal tip of the CVC should be placed at the junction between the superior cava vein and right atrium; anticoagulants are not recommended. Treatment of CVC-associated thrombosis should be based on the prolonged use of low-molecular weight heparins. Maintenance of the catheter is justified if it is mandatory, functional, in the right position, and not infected, with a favorable clinical evolution under close monitoring; anticoagulant treatment should then be continued as long as the catheter is present. CONCLUSIONS: Several rigorous studies do not support the use of anticoagulants for the prevention of CVC-associated thrombosis. Treatment of CVC-associated thrombosis relies on the same principles as those applied in the treatment of established thrombosis in cancer patients.

[Central venous lines in children: new trends]. / Voies veineuses centrales chez l'enfant: quoi de neuf?

Central venous catheterisation under two-dimensional ultrasound (US) guidance has been proved to be quicker and safer than the classical landmark method in both adults and children. In the literature US guidance with sterile dressing of the probe is the 'gold-standard'. Another way to use US is simple preoperative US location followed either by blind puncture, either by US guided puncture when difficulties are expected: small infants (<15 kg), small diameter or collapses of the vein, multiple unsuccessful attempts during blind technique. Ideal location of the tip of central venous catheters is no more controversial but can depend on age and weight. In 2002 a French agency (Afssaps) study showed that the risk of perforation and tamponade was especially high in small weight prematures with 27 gauge polyurethane catheters when tip was located in the cardiac cavities. In children and adults venous thrombosis and catheter malfunction are closely related to short catheters whose tip is above T3-T4. Excepted polyurethane catheters in small weight prematures, the best location of long-term central venous catheters tip is the superior vena cava-right auricle junction. At this time routine antithrombotic prophylaxis is not recommended for children with long-term central venous catheters.

Airway obstruction and high-frequency jet ventilation during laryngoscopy.

High-frequency jet ventilation has been reported as an effective method of ventilation during laryngoscopy, but may expose the patient to the risks of barotrauma or alveolar hypoventilation. The aim of the study was to evaluate the determining factors of pulmonary complications under high-frequency jet ventilation in 83 patients undergoing laryngoscopy for upper airway cancer. Pulmonary distention was mainly influenced by upper airway obstruction score (p = .0001), while patients with chronic obstructive pulmonary disease (COPD) did not suffer from gas trapping. Impaired gas exchange was predicted by increased weight (p = .0001), smaller injector diameter (p = .02), and lower airway obstruction (p = .001). Hypercapnia occurred in both upper and lower airway obstruction, while hypoxemia was principally observed in COPD patients. Emphasis is placed on monitoring by pulse oximetry, end-expiratory pressure, and PCO2 measurement, especially in patients with obesity, COPD, or upper airway obstruction.

[Nosocomial risk factors of hepatitis C infection. A multicenter study in a hospital-based population]. / Facteurs de risque nosocomiaux de l'infection par le virus de l'hépatite C. Une étude multicentrique en population hospitalière.

PURPOSE: Drug abuse and blood transfusion are well known risk factors for hepatitis C virus (HCV) infection. However, the route of transmission remains undetermined for 30% of HCV infections. The potential for nosocomial transmission of HCV in health care settings has been suggested but remains poorly estimated. The aim of the study was to assess the prevalence and to identify risk factors for hepatitis C virus (HCV) infection in hospitalized patients frequently exposed to invasive procedures. METHOD: A multi-center sero-prevalence study was conducted in hospitalized patients who underwent invasive procedures in interventional radiology wards in 6 University hospitals in Paris between 1998 and 1999. Each patient presenting in the ward was consecutively interviewed by a medical investigator. Data were collected on a standardized questionnaire including items on socio-demographic characteristics, past exposure to intravenous drug use, blood transfusions, underlying diseases and type and number of previous invasive procedures. Before procedure, HCV antibody testing (ELISA) was performed in all patients after informed consent. In all HCV-positive patients, HCV viremia was detected using polymerase chain reaction. RESULTS: Overall, 91 of 944 (9.7%) patients were HCV-positive, of whom 90% had positive viremia and 10 were identified HCV positive by the screening. HCV prevalence decreased with age and ranged from 4.5% to 22% according to center. Logistic regression analysis showed that intravenous drug use, history of blood transfusions and endoscopy were found as independent risk factors for HCV infection (odds ratio [CI95%]: 77.3 [23.3-256.3], 4.7 [2.7-8.2] et 1.20 [1.01-1.44]). No other risk factor for nosocomial or iatrogenic transmission was identified. CONCLUSION: The results suggest that, except for blood transfusions, other healthcare-related procedures may partly explain HCV transmission. This emphasizes the need to reinforce compliance with standard precautions of hygiene.

[Transtracheal jet ventilation with spontaneous ventilation in neoplastic laryngeal dyspnea]. / Jet-ventilation transtrachéale avec ventilation spontanée lors des dyspnées laryngées d'origine néoplasique.

In six suffocating patients with a severe upper airway obstruction (three patients after direct laryngoscopy under general anaesthesia and three patients with cervical tumor scheduled for a difficult tracheostomy), jet-ventilation was delivered using a transtracheal catheter. The jet-ventilator insufflated oxygen only when the tracheal pressure was below a preset value, during spontaneous inspiration. During expiration, tracheal pressure increased above the preset value, the ventilator stopped the insufflation and the expiratory gases escaped through the upper airway. This method corresponds to an inspiratory support without intubation. In post-anaesthesia patients, oxygenation and alveolar ventilation were improved, allowing the avoidance of tracheostomy. In the other patients, tracheostomy was made possible with good surgical conditions under general anaesthesia. This method can be applied in conscious patients and allows oxygenation of suffocating patients.

[Stomach rupture after nasal oxygen administration]. / Rupture gastrique après oxygénothérapie par voie nasale.

We report a case of a spontaneous rupture of a normal stomach after therapeutic oxygen administration. In this case, early treatment precluded the need for a laparotomy. This rare complication highlights the importance of the right positioning of a nasal catheter and leads us to question its role compared to other means of oxygen delivery (nasal cannulae, Hudson mask, Venturi mask).

[The pinch-off syndrome: main cause of catheter embolism]. / Le syndrome de la pince costoclaviculaire: principale cause d'embolie de cathéter.

OBJECTIVE: To assess the incidence of the pinch-off syndrome (POS) in catheter fracture and embolism. STUDY DESIGN: Retrospective clinical study. PATIENTS: The medical files of 56 patients who had since 1989 an embolized fragment or entire catheter removed by an interventional radiologic procedure have been retrospectively analysed. METHODS: A POS was considered the causative factor when a chest X-ray showed a rupture of the catheter at the site of the costoclavicular space. RESULTS: From 1989 to the end of 1996, 56 catheter embolisms by fracture or disconnection occurred in our institution. The rupture from a POS was the main cause of embolism (24 patients out of 56). The incidence was 8/1000 of implanted ports inserted via a subclavian access [95% confidence interval: 4/1000-13/1000]. Preliminary clinical or radiologic signs of pinching existed in 50% of POS: difficult insertion, radiologic compression aspect, arm or shoulder pain, infusion rate and/or reflow depending on arm position. CONCLUSIONS: POS was the first cause of catheter embolism and should suggest the use of an alternative way for insertion instead of the subclavian access. When a catheter is inserted via a subclavian route, clinical and/or radiologic signs of POS require its removal.

[Cutaneous localization of multiple myeloma on the tract of a central venous catheter]. / Localisations cutanées d'un myélome sur le trajet de voies veineuses centrales.

INTRODUCTION: Extramedullary plasmocytoma are plasmocytic tumours developing outside of the bone marrow. Cutaneous localization of extramedullary plasmocytoma are rare and can be primitive or secondary. We report two cases of secondary extramedullary plasmocytoma occurring on central venous catheterization sites. OBSERVATIONS: A 68 year-old woman and a 69 year-old man presented with subcutaneous metastases located along the tracts of central venous catheters or implantable ports, which were either still on site or removed recently. Although the patients initially responded to melphalan therapy, they eventually died of multiple myeloma a few weeks following the diagnosis of the cutaneous localizations. DISCUSSION: Extramedullary plasmocytoma are most commonly found in the upper respiratory tract, the gut and the lymph, but cutaneous localization is rare. We report two cases of cutaneous extramedullary plasmocytoma located on the tract of central intravenous infusion sites. Both patients were treated with melphalan with initial improvement, followed by an early relapse. Two cases of myeloma metastases occurring on the tract of central venous catheters have previously been published. This localization seems to occur late in the course of this disease and to be associated with a poor prognosis.

[150 hepatic resections of malignant tumors. Technical aspects]. / 150 résections hépatiques pour tumeurs malignes. Aspects techniques.

One hundred and fifty hepatic resections for liver tumors have been performed in 130 patients during the last six years. The origin of the tumors was miscellaneous, but 76 resections were made for liver metastases from colo-rectal cancers, and all the types of hepatic resections were performed. The post-operative mortality and morbidity were respectively 2% and 26%. After such an experience, we think that hepatic resections for tumors are currently safe surgical operations. This security comes from two technical ameliorations: the practice of intraoperative ultrasonography and the systematic use of repetitive pedicular clampings. A detailed account is done about the different operative technics concerning intraoperative ultrasonography, pedicle clamping and different types of systematized or atypical hepatectomies.

[Surgical approaches to segment I for malignant tumors (20 cases)]. / Approches chirurgicales du segment I pour tumeurs malignes (20 cas).

Seven complete and 13 partial resections of segment I (caudate lobe) were performed for malignant tumors. In all except one instance, removal of segment I was combined with other types of hepatic resection for technical or carcinologic reasons. Six were iterative hepatic resections for recurrent hepatic metastases. In two, the future remaining left lobe was hypertrophied by right portal venous embolization preoperatively. Hepatectomies were performed with intermittent portal triad clamping (mean total duration of 63 minutes, range of 20 to 120 minutes) and after preparation for total vascular exclusion. Associated partial resection of the inferior vena cava was necessary in three instances. Mean duration of operation was 285 minutes (range of 60 to 540 minutes) and mean blood loss was 1,749 milliliters (range of 200 to 5,200 milliliters). There was no postoperative mortality and the morbidity rate was low. Surprisingly, we discovered retrospectively that free margins were small (less than 5 millimeters) in 83 percent of the patients. Regardless of limited free margins and six iterative hepatectomies, eight patients were free of disease with a mean follow-up examination period of 19.2 months. Technical problems were different for each patient and a patient by patient adaptation was necessary. Left, right and central approaches were used accordingly. If resection of segment I associated with a right of left hepatectomy can currently considered as a standard hepatic resection, isolated complete resection of segment I remains a real technical challenge.

[Mechanical complications at implantation sites]. / Complications mécaniques des sites implantés.

Mechanical complications of implanted venous access devices are more common than suggested by the literature. Among them, the most severe is catheter embolism, which is due primarily to costoclavicular pinch-off syndrome (POS). POS occurs mainly after infraclavicular approach of the subclavian vein, the incidence being 8/1000 in our experience. Clinical and radiological findings suggestive of rupture should be well known since they require removal of the device. Other access sites (internal jugular vein, cephalic vein, subclavian vein by the supraclavicular approach) seem preferable for long-term catheterization. Loss of adaptation between the site and catheter, precipitated by inopportune attempts at relieving obstruction or by a defective connector, is the second most common cause of embolism. Irrespective of the cause, the embolized fragment must be removed using vascular interventional radiological techniques in order to avoid severe thrombo-embolism. Thrombo-embolism can also result from secondary migration into a vein adjacent of a catheter that was properly positioned initially. This complication can be produced by forceful injections or by intrathoracic pressure changes generated by coughing or intrathoracic disorders. Clinicians should watch carefully for the evidence of central venous line dysfunction that usually accompanies these complications.

Prolonged intermittent clamping of the portal triad during hepatectomy.

From 112 consecutive hepatectomies for malignant tumours performed with intermittent portal triad clamping, we have retrospectively selected the 20 cases in which clamping exceeded 90 min. Intermittent portal clamping of prolonged duration was used because of abnormal liver texture in 13 cases (mainly patients who had received intra-arterial chemotherapy) and/or because of technically difficult hepatectomy. The mean(s.d.) duration of intermittent portal clamping was 109(18) min and in two cases it exceeded 140 min (148 and 150 min). There was no postoperative mortality and the rate of postoperative morbidity was 35 per cent. Postoperative changes in biochemical liver tests were not major and transient hepatic failure occurred in only one patient following subtotal resection of the liver. We conclude that intermittent portal clamping is a useful manoeuvre in partial hepatectomy when resection is difficult or prolonged, or when the liver parenchyma is abnormal. Such clamping may be used for longer than 120 min without major complications.

Transtracheal high frequency jet ventilation for endoscopic airway surgery: a multicentre study.

Serious complications during high frequency jet ventilation (HFJV) are rare and have been documented in animals and in case reports or short series of patients with a difficult airway. We report complications of transtracheal HFFJV in a prospective multicentre study of 643 patients having laryngoscopy or laryngeal laser surgery. A transtracheal catheter could not be inserted in two patients (0.3%). Subcutaneous emphysema (8.4%) was more frequent after multiple tracheal punctures. There were seven pneumothoraces (1%), two after laser damage to the injector, one after difficult laryngoscopy, four with no clear cause. Arterial desaturation of oxygen was more frequent during laser surgery and in overweight patients. Transtracheal ventilation from a ventilator with an automatic cut-off device is a reliable method for experienced users. Control of airway pressure does not prevent a low frequency of pneumothorax.

Surgical approach to segment I for malignant tumors of the liver.

Seven complete and 13 partial resections of segment I (caudate lobe) were performed for malignant tumors. In all except one instance, removal of segment I was combined with other types of hepatic resection for technical or carcinologic reasons. Six were iterative hepatic resections for recurrent hepatic metastases. In two, the future remaining left lobe was hypertrophied by right portal venous embolization preoperatively. Hepatectomies were performed with intermittent portal triad clamping (mean total duration of 63 minutes, range of 20 to 120 minutes) and after preparation for total vascular exclusion. Associated partial resection of the inferior vena cava was necessary in three instances. Mean duration of operation was 285 minutes (range of 60 to 540 minutes) and mean blood loss was 1,749 milliliters (range of 200 to 5,200 milliliters). There was no postoperative mortality and the morbidity rate was low. Surprisingly, we discovered retrospectively that free margins were small (less than 5 millimeters) in 83 percent of the patients. Regardless of limited free margins and six iterative hepatectomies, eight patients were free of disease with a mean follow-up examination period of 19.2 months. Technical problems were different for each patient and a patient by patient adaptation was necessary. Left, right and central approaches were used accordingly. If resection of segment I associated with a right or left hepatectomy can be currently considered as a standard hepatic resection, isolated complete resection of segment I remains a real technical challenge.

Measurement of end-expiratory pressure during transtracheal high frequency jet ventilation for laryngoscopy.

An anaesthetic technique using high frequency jet ventilation has been proposed for direct laryngoscopy, but this may expose the patients to the risk of barotrauma. In order to assess this risk, we have measured end-expiratory airway pressure (EEP) through the injector using two three-way solenoid valves mounted in series. At the end of insufflation the first valve was switched off and the apparatus deadspace connected to atmosphere through a large exit port during an adjustable time (decompression time). Then the second valve was switched off and the injection line connected to a transducer, allowing measurement of EEP through the injector. The accuracy of this measurement was tested against airway pressure measured directly in the trachea (Pt) in a lung model. Provided that the decompression time was long enough (70 ms) and the apparatus deadspace was small (6 ml), the difference between EEP and Pt was less than 1 cm H2O for frequencies up to 5 Hz. A clinical evaluation was performed in 64 patients under general anaesthesia before laryngoscopy. EEP correlated with end-expiratory pulmonary volume above apnoeic FRC inferred from abdominal and thoracic displacements. At jet frequencies up to 5 Hz, the correlations between these two variables were satisfactory (r greater than 0.88), suggesting that EEP is a good indicator of pulmonary overdistension.