Iatrogenic cardiac tamponade after central venous catheter

Feasibility and Safety of a Technique Intended to Place the Catheter Tip in the Right Atrium without Abutment Against the Cardiac Wall during Implantation of the Totally Implantable Venous Access Port

Purpose

To assess the safety and feasibility of intentionally positioning the catheter tip in the right atrium (RA) without an abutment during implantation of a totally implantable venous access port (TIVAP).

Materials and Methods

We enrolled 330 patients who had undergone TIVAP implantation between January and December 2016 and postoperative chest CT. The TIVAP was placed using the single-incision technique to access the axillary vein directly from the incision line. To position the catheter tip in the RA without abutment, blood return was checked before cutting. Catheter length and complications were evaluated by retrospectively reviewing medical images and records.

Results

All patients achieved successful catheter tip positioning without abutment or dysfunction. The median tip position was 15.3 mm distal to the cavoatrial junction (CAJ) on fluoroscopy and 6 mm distal to the CAJ on CT. Catheter tips migrated a median of 10.4 mm cephalically on CT compared to fluoroscopy. Thromboses were detected in the RA and superior vena cava in one patient each.

Conclusion

Intentional catheter tip positioning in the RA without abutment is a safe and feasible technique with a low incidence of thrombosis and no observed dysfunction.

Precise Terminology and Specified Catheter Insertion Length in Ultrasound-Guided Infraclavicular Central Vein Catheterization

Background and Objectives: As the latest research encourages the ultrasound-guided infraclavicular central venous approach, due to the lateral puncture site displacement, in comparison to the anatomical landmark technique based on subclavian vein catheterization, the need to re-calculate the optimal catheter insertion length and possibly to rename the punctuated vessel emerges. Although naming a particular anatomical structure is a nomenclature issue, a suboptimal catheter position can be associated with multiple life-threatening complications and must be avoided. The main study objective is to determine the optimal catheter insertion length by the most proximal ultrasound-guided, in-plane infraclavicular central vein approach, to compare results with the anatomical landmark technique based on subclavian vein catheterization and to clarify the punctuated anatomical structure. Materials and Methods: 109 patients were enrolled in this study. All procedures were performed according to the same catheterization protocol. In order to determine optimal insertion length, chest X-ray scans with an existing catheter were performed. The definition of punctuated vessel was based on computer tomography and evaluated by radiologists. Independent predictors for optimal insertion length were identified, prediction equations were generated. Results: The optimal catheter insertion length is approximately 1.5 cm longer than estimated by Pere's formula and can be accurately calculated based on anthropometric data. Computed tomography revealed: five cases with subclavian vein puncture and three cases with axillary vein puncture. Conclusions: Even the most proximal ultrasound-guided infraclavicular central vein access does not guarantee subclavian vein catheterization. A more accurate term could be infraclavicular central venous access, with the implication that the entry point could be through either subclavian or axillary veins. The optimal insertion length is approximately 1.5 cm deeper than the length determined for the anatomical landmark technique based on subclavian vein catheterization.

Development and validation of an updated PICC length prediction formula based on anteroposterior chest radiographs for the ultrasound-guided bedside placement

Bedside peripherally inserted central catheter (PICC) placement is sometimes required when the patient's intrahospital transport is restricted, and the ideal catheter length prediction is needed. This study aimed to develop an updated formula that predicts the optimal length of a PICC based on anteroposterior chest radiographs (AP-CXRs). This retrospective study collected PICC procedure data as the training and validation sets in three hospitals, including cubital crease-puncture point distance (CP), the actual PICC length (aCL), and the approach side. Horizontal and vertical measurement variables were set on the AP-CXRs. Two dependent variables were ipsilateral upper arm length (AL) and ideal truncal catheter length (iTCL). Simple and multiple regression analyses were used for formula development, and it was applied to the test set to evaluate the length prediction performance. The study included 309 patients in the training and validation sets and 91 intensive care patients in the test set. The final derived formula was: (AL + iTCL = CP + estimated PICC length, cm) = 19.831 - 0.062 × (contralateral clavicle length, cm) + 0.255 × (2nd ribs horizontal distance, cm) + 0.720 × (humero-vertebral distance, cm) + 0.761 × (thoraco-carinal distance, cm) + 1.024 × (the vertical distance of two vertebral body units, cm). (If approaching from the left, add 2.843cm, and if female, subtract 0.821cm.) In the test set, there was no case of length prediction failure. Moreover, the catheter tip position was evaluated as optimal in 82 cases (90.1%). This study's results suggest an updated formula to predict the ideal PICC length using only AP-CXRs for bedside placement.

Iatrogenic Cardiac Tamponade Secondary to Central Venous Catheter Placement: A Literature Review

Cardiac tamponade is the fluid accumulation within the pericardial sac that compresses the heart and decreases cardiac output. More than 20% of the cases are surgical or non-surgical iatrogenic causes. Cardiac tamponade has been described as a rare complication of central venous catheter placement with an incidence in adults as low as less than 1% but with significantly high mortality of more than 60%. The purpose of this article is to review the incidence, clinical manifestations, pathophysiology, diagnosis, and management of cardiac tamponade after central venous catheter placement as well as different methods to prevent this fatal complication from occurring.

Iatrogenic Causes of Cardiac Tamponade Resulting From Surgical Procedures: An Overview

Cardiac tamponade is one of the most severely life-threatening emergencies encountered, mainly because of its significant impact on the pumping capacity of the heart by compressing the cardiac chambers due to the rapid accumulation of blood, fluid, pus, or clots in the pericardial sac. These accumulations may be collected following traumas, malignancies, uremia, and many other medical conditions as well as surgical procedures. Numerous errors and medicolegal aspects have been identified in diagnosing and treating cardiac tamponade associated with cardiac-related procedures such as valve replacement surgeries, cardiac pacemaker implantation, pericardiocentesis, and other non-cardiac related procedures such as peri-hiatal surgeries. Patients taking anticoagulants or anticancer medications are especially susceptible to developing cardiac tamponade when undergoing surgical procedures, raising the question of preoperative screening to avoid errors. Misdiagnosis, treatment delay or failure to deliver the utmost quality of treatment, lack of complication screening and follow-ups for those at risk, surgeons rushing to complete cases, burnout, and other human factors are predispositions to the development of cardiac tamponade. Fortunately, most of these errors occurring within healthcare settings are avoidable and must be prevented for eliminating any risks to reduce the incidence and mortality of cardiac tamponade cases resulting from iatrogenic etiology. It is an intricate condition where precision and caution are crucial.

Validation of the PICC length prediction formula based on anteroposterior chest radiographs for bedside ultrasound-guided placement

This study aimed to validate the accuracy of the peripherally inserted central catheter (PICC) length prediction formula using only anteroposterior chest radiographs (AP-CXR) and the technical feasibility of bedside ultrasound-guided PICC placement. This study included 156 Asian adult patients who underwent bedside PICC placement at three hospitals from September 2021 to March 2022. The shortest straight-line distance from the cubital crease to the puncture point (CP) was measured first. Using the formula of a previous study, the CP + estimated PICC length (eCL) was calculated with the parameters measured on AP-CXR. The formula was as follows: 19.409 + 0.424 × (MHTD, maximal horizontal thoracic diameter) + 0.287 × (CL, clavicle length) + 0.203 × (DTV, distance of thoracic vertebrae) + (2VBUs, two vertebral body units below the carina inferior border) (if from the left, 3.063cm was added; if female, 0.997cm was subtracted). Catheters were pretrimmed according to calculated eCL prior to the procedure. Technical success was evaluated, and the validation success of catheter length prediction was classified according to the catheter tip position as follows: optimal position or suboptimal position. Technical success was achieved in 153 cases (98.1%). Evaluation of validation success revealed that the position was “optimal” in 108 cases (70.6%) and “suboptimal” in 45 cases (29.4%). There was no validation failure. There was no case where the catheter was inserted too deep as to wedge into the right atrial wall. In conclusion, the PICC could be positioned accurately using the formula based on only AP-CXR. Furthermore, this bedside procedure was technically feasible.

Fatal iatrogenic cardiac tamponade due to central venous catheterization

Fatal adverse events caused by any health professional as consequence of malpractice are uncommon. In this work, the authors report a fatal cardiac tamponade associated with a peripherally inserted central catheter (PICC) by the right jugular vein that perforated the right atrium of the heart. The diagnosis of cardiac tamponade was not detected in hospital during the intrapericardial infusion of total parenteral nutrition and was only registered during the autopsy. The postmortem examination showed a milky liquid inside the pericardial cavity compatible with the total parenteral nutrition administered. The catheter in its migration in the cardiac chambers, mechanically perforated the inner wall of the endocardium between the trabeculae carneae, continued its course between the myocardial fibers until it was externalized. In conclusion, cardiac tamponade, although it is an extremely rare medical complication, has a high risk of fatality specially if peripheral rather than central veins were cannulated.

Hickman catheter-induced cardiac tamponade-related cardiac perforation management by mediastinotomy in children and a review of the literature

Objective

Hickman catheter placement rarely causes cardiac tamponade due to cardiac perforation in children. Cardiac perforation can be managed with timely perceive and appropriate approach. We present a case of the cardiac perforation related to Hickman catheter insertion in a 7-year-old girl and a review of the supporting literature.

Case report

The patient had previous history of Thalassemia and admitted to hospital for Hickman catheter placement for bone marrow transplantation. The catheter was placed in the right internal jugular vein by ultrasonography. During the postoperative period she had hypoxia, hypotension and tachycardia. The patient underwent an emergency surgery and there was a small perforation between vena cava superior and right atrium. That wound was managed by mediastinotomy. The patient was discharge on the 8th postoperative day.

Conclusion

Cardiac perforation is one of the rare and unexpected complications of Hickman catheter placement. Unfortunately, the complication may cause significant mortality. The prompt diagnosis and early intervention provides satisfactory results.

Transoesophageal echocardiographic evaluation of central venous catheter positioning using Peres' formula or a radiological landmark-based approach: a prospective randomized single-centre study

BACKGROUND

The lower superior vena cava (SVC), near its junction with the right atrium (RA), is considered the ideal location for the central venous catheter tip to ensure proper function and prevent injuries. We determined catheter insertion depth with a new formula using the sternoclavicular joint and the carina as radiological landmarks, with a 1.5 cm safety margin. The accuracy of tip positioning with the radiological landmark-based technique (R) and Peres' formula (P) was compared using transoesophageal echocardiography.

METHODS

Real-time ultrasound-guided central venous catheter insertion was done through the right internal jugular or subclavian vein. Patients were randomly assigned to either the P group (n=93) or the R group (n=95). Optimal catheter tip position was considered to be within 2 cm above and 1 cm below the RA-SVC junction. Catheter tip position, abutment, angle to the vascular wall, and flow stream were evaluated on a bicaval view.

RESULTS

The distance from the skin insertion point to the RA-SVC junction and determined depth of catheter insertion were more strongly correlated in the R group [17.4 (1.2) and 16.7 (1.5) cm; r=0.821, P<0.001] than in the P group [17.3 (1.2) and 16.4 (1.1) cm; r=0.517, P<0.001], with z=3.96 (P<0.001). More tips were correctly positioned in the R group than in the P group (74 vs 93%, P=0.001). Abutment, tip angle to the lateral wall >40°, and disrupted flow stream were comparable.

CONCLUSIONS

Catheter tip position was more accurate with a radiological landmark-based technique than with Peres' formula.

CLINICAL TRIAL REGISTRATION

Clinical Trial Registry of Korea: https://cris.nih.go.kr/cris/index.jsp KCT0001937.

The malposition of a central venous catheter through a sheath introducer via the left internal jugular vein: A case report

RATIONALE

The misplacement of central venous catheter (CVC) can occur more often at the left jugular vein than the right side due to anatomic differences. And many of the previously reported cases are about catheter misplacement resulting from vessel penetration associated with guidewire. This case differs that the catheter itself through the sheath introducer can cause venous injury that may lead to the malposition of CVC particularly through an approach to the left internal jugular vein.

PATIENT CONCERNS, DIAGNOSIS, INTERVENTIONS, AND OUTCOMES

We cannulated a large-bore CVC with a sheath introducer, namely mult-lumen access catheter (MAC) in the left jugular vein of patient under anesthesia using ultrasound and inserted the additional central venous oximetry catheter through the sheath introducer of MAC and confirmed aspiration of blood. However, the postoperative imaging study revealed malposition of the tip of the oximetry catheter in the mediastinum.

MAIN LESSON

The insertion of additional catheter through the sheath introducer needs to be carried out as carefully as the insertion of guidewire and should be confirmed with imaging study after the procedure.

Prediction of the optimal depth for superior vena cava cannulae with cardiac computed tomography during minimally invasive cardiac surgery: a prospective observational cohort study

BACKGROUND

The determination of the adequate depth of superior vena cava cannulae during minimally invasive cardiac surgery is important for warranting venous drainage and preventing complications during cardiopulmonary bypass. We investigated whether preoperative cardiac computed tomography might be useful for predicting the optimal depth of superior vena cava cannulae.

METHODS

The patients who required superior vena cava cannulation and had cardiac tomographic image among those scheduled to undergo a minimally invasive cardiac surgery were evaluated. The distance between the upper border of the clavicular sternal head and the superior vena cava-right atrium junction was measured on cardiac computed tomography. Equivalence test for the difference between the distance measured on cardiac computed tomography and the distance verified by surgeon's direct inspection in the surgical field was performed. The range -1 cm to 1 cm was predefined as an equivalence region. In addition, the distances between the upper border of the clavicular sternal head and the carina level on chest radiography were measured to compare the relative position of carina with regard to the superior vena cava-right atrium junction.

RESULTS

A total of 46 patients were evaluated. The distance from the upper border of the clavicular sternal head to the superior vena cava-right atrium junction measured on cardiac computed tomography and the distance verified by surgeon's inspection was equivalent, with the 95% confidence interval for the mean difference within the equivalence region (0.05-0.52, P < 0.0001). The carina level on chest radiography was found at least 2 cm above the superior vena cava-right atrium junction in all patients.

CONCLUSIONS

Preoperative cardiac computed tomography might be valuable for predicting the adequate depth of superior vena cava cannulae. Additionally, the carina on chest radiography might indicate a useful landmark for proper position of central venous catheter.

TRIAL REGISTRATION

This study has been registered at Clinical Research Information Service on 6 July 2012 (KCT0000477) .

Pericardial and Pleural Effusion after Central Venous Line Insertion

A large volume of fluid collected in the pericardium and left pleural space following central venous catheter insertion for total parenteral nutrition in a 35-year-old man. This did not cause fatal hemodynamic compromise and was successfully diagnosed and treated.

An unusual complication of atrial fibrillation ablation: case report

The authors report a complication of catheter ablation that, to their knowledge, has never been previously reported. A 63-year-old man had undergone successful transvenous catheter thermoablation for atrial fibrillation. The patient remained well until 3 days prior to further admission when he noticed itching in the right frontal area of his scalp. On palpating his scalp, he discovered a metallic body projecting out of it and he proceeded to extract 20 cm of wire from his head. The following day a progressive left hemiplegia developed, and the patient experienced a deteriorating level of consciousness. A CT scan of the brain showed a right frontotemporal intraparenchymal hemorrhage and revealed a metallic structure in the middle of the hematoma. The hematoma was evacuated and a decompressive craniotomy was performed. The guidewire was identified, but it was only possible to extract part of it. It was covered by fibrous tissue, secondary to inflammatory reaction. To the authors' knowledge, this is the first report of guidewire-induced brain hemorrhage. The guidewire apparently had not been removed and had spontaneously migrated from the heart to the brain and beyond to the scalp where it then exited the patient's head. The patient had been well before he attempted to pull out the wire. Earlier identification of the iatrogenic complication of a retained guidewire might have prevented the fatal outcome in this case.

[Cardiac tamponade after withdrawal of a peripheral access central catheter]

Central venous catheterization is a very common technique, although its complications can be multiple and sometimes fatal. A case is presented of cardiac tamponade by parenteral nutrition a few hours after moving a central venous catheter peripherally inserted a few days before. The diagnosis was made by echocardiography, and an emergency pericardiocentesis was performed, achieving complete recovery of the patient. Peripherally inserted central venous catheters are more likely to change their position secondary to the movements of the patient's arm, thus it is important to use soft catheters, make sure the tip lies above the carina to avoid perforation of the pericardial reflexion, and fix it well to the skin. Diagnosis must be made as soon as possible, given the high mortality rate of this complication, and the essential diagnostic tool is echocardiography. Elective treatment consists of early catheter withdrawal and emergency pericardiocentesis.

Emergent Median Sternotomy for Mediastinal Hematoma: A Rare Complication following Internal Jugular Vein Catheterization for Chemoport Insertion-A Case Report and Review of Relevant Literature

Mediastinal hematoma is a rare complication following insertion of a central venous catheter with only few cases reported in the English literature. We report a case of a 71-year-old female who was admitted for elective chemoport placement. USG guided right internal jugular access was attempted using the Seldinger technique. Resistance was met while threading the guidewire. USG showed a chronic clot burden in the RIJ. A microvascular access was established under fluoroscopic guidance. Rest of the procedure was completed without any further issues. Following extubation, the patient complained of right-sided chest pain radiating to the back. Chest X-ray revealed a contained white out in the right upper lung field. She became hemodynamically unstable. Repeated X-ray showed progression of the hematoma. Median Sternotomy showed posterior mediastinal hematoma tracking into right pleural cavity. Active bleeding from the puncture site at RIJ-SCL junction was repaired. Patient had an uneventful recovery. Injury to the central venous system is the result of either penetrating trauma or iatrogenic causes as in our case. A possible explanation of our complication may be attributed to the forced manipulation of the dilator or guidewire against resistance. Clavicle and sternum offer bony protection to the underlying vital venous structures and injuries often need sternotomy with or without neck extension. Division of the clavicle and disarticulation of the sternoclavicular joint may be required for optimum exposure. Meticulous surgical technique, knowledge of the possible complications, and close monitoring in the postprocedural period are of utmost importance. Chest X-ray showed to be routinely done to detect any complication early.

Optimal insertion depth of central venous catheters--is a formula required? A prospective cohort study

INTRODUCTION

To determine the optimal length for initial insertion of central venous catheters (CVCs) and to evaluate whether a recommended depth predicted optimal positioning of CVCs.

MATERIALS AND METHODS

All patients who were CVC-cannulated and who underwent chest computed tomography (CT) during a 10-month period were included. We measured the distance from catheter insertion to the superior vena cava/right atrium (SVC/RA) junction and calculated a recommended insertion depth. We compared the accuracy of the recommended depth with that suggested by the formula of Peres for predicting optimal positioning of a CVC.

RESULTS

Of the 1238 patients who were CVC-cannulated over 10 months, 106 underwent chest CT. Based on the mean distance from the CVC insertion point to the distal SVC, we determined that the recommended depth of insertion should be 14 cm for the right subclavian vein, 15 cm for the right internal jugular vein, 17 cm for the left subclavian vein and 18 cm for left internal jugular vein. Using these guidelines, initial placement of a CVC in the distal SVC was more accurate than when the Peres formula was used (91.5% vs. 77.4%, p<0.05).

CONCLUSIONS

For Asian populations, we found that these guidelines are more accurate than those derived from the Peres formulae and more simple to use, thus increasing the likelihood of optimal tip location within the SVC on the first attempt and eliminating the need for later repositioning.

A better landmark for positioning a central venous catheter

BACKGROUND

Improper positioning of central venous catheters (CVCs) can lead to erosion through the superior vena cava (SVC) or right atrium (RA) and pericardial tamponade. It is widely recommended that the tip of CVCs be placed above the heart or the pericardial reflection. The purpose of this study was to identify an easily recognized landmark to allow identification of the proximal extent of the pericardial reflection on a routine chest radiograph (CXR).

METHODS

We analyzed the computerized tomograms of the chest from 97 adults to evaluate the relationship between the pericardial reflection, SVC, carina, and right mainstem bronchus. Correlations between demographic data and length of SVC or pericardial reflection were sought.

RESULTS

The mean length of the SVC was 6.5 cm. The pericardial reflection covered an average of 3.6 cm of the distal SVC. The carina was a mean of 1.3 cm below the mid-point of the SVC and 0.7 cm below the pericardial reflection. There was no significant correlation between SVC or pericardial length and either age, height, or weight.

CONCLUSIONS

The distal half of the SVC lies within the pericardial reflection, and the upper limit of the pericardial reflection is slightly above the level of the carina. These landmarks are useful for determining proper position of the tip of a CVC on CXR.

MRI of central venous anatomy: implications for central venous catheter insertion

STUDY OBJECTIVES

To determine normative values for superior vena cava (SVC) length and the utility of radiographic landmarks for identifying the boundaries of the SVC for assisting central line placement.

DESIGN

Cross-sectional study.

SETTING

Urban tertiary care medical centers.

PATIENTS

Patients undergoing thoracic MRI scanning for various indications.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

The SVC dimensions and relationship to radiographic landmarks were determined from MRI scans of 42 patients (22 men, 20 women; median age, 57 years). The median length of the SVC was 6.8 cm (range, 4.4 to 10.0 cm) and did not correlate with gender or other measured cardiovascular dimensions. The right tracheobronchial angle was the best radiographic landmark for determining the cephalad origin of the SVC being always caudad and within a median of 1.5 cm (range, 0.1 to 3.8 cm) of the upper SVC. It was always at least 2.9 cm above the atriocaval junction. The right superior heart border was formed by the left atrium in 38% (95% confidence interval, 23 to 53%) of patients and did not reliably identify the atriocaval junction.

CONCLUSIONS

The right tracheobronchial angle is the most reliable landmark for the upper margin of the SVC. Venous catheters placed caudad to this landmark and cephalad to the right superior cardiac silhouette or no more than 2.9 cm caudad to the tracheobronchial angle result in catheter tips within the SVC.

Cardiac tamponade from central venous catheters

BACKGROUND

This retrospective study was undertaken to determine the mechanism by which cardiac tamponade (CT) occurs after placement of central venous catheters (CVC), and to determine if physicians are aware of this potentially lethal complication.

MATERIALS AND METHODS

Twenty-five previously unreported cases of CT from CVC were reviewed. The chest radiographs and postmortem records were reviewed when available. Two hundred physicians were interviewed about their knowledge of CT from CVC. They were specifically asked if they had reviewed the three-volume video, "CVC Complications," that was sent by the Food and Drug Administration to all hospitals where CVC are inserted.

RESULTS

All postinsertion chest radiographs showed the tip of the catheter to be within the pericardial silhouette. All patients developed unexplained hypotension from hours to 1 week after CVC placement. Eight patients complained of chest tightness, 12 of shortness of breath, and 15 were noted to have air hunger. The electrocardiogram showed inferior wall injury in 7 patients. None of the physicians surveyed had seen the FDA video.

CONCLUSIONS

Cardiac tamponade from central venous catheters is preventable if the tip of the catheter is outside the cardiac silhouette on chest radiograph. Any patient with a CVC in place who develops unexplained hypotension, chest tightness, or shortness of breath should have an emergency echocardiogram to rule out cardiac tamponade.

Depth of central venous catheter insertion in adults: an audit and assessment of a technique to improve tip position

A technique of subclavian vein catheterization is described, tailored to the individual patient, to reduce the risk of right atrial placement with central venous catheter (CVC) insertion. Using data gathered retrospectively for Quality Improvement purposes, CVC tip location was assessed. The standard technique used in our cardiac anaesthesia unit at that time was to insert all CVCs to a depth of 15 cm from the skin. We then compared CVC tip location using a new "tailored" technique. The tailored method involved measuring the distance from the skin at which venepuncture occurred and using this distance to determine depth of CVC insertion. Using the tailored technique significantly decreases the frequency with which CVC tips enter the right atrium (P < 0.001). An advantage of the tailored technique is that the distance between the most proximal and the distal ports of multi-lumen CVCs is taken into consideration, reducing the risk of extravasation via the proximal port.

Cardiac tamponade in an infant. A rare complication of central venous catheterisation

A 2994 g infant suffered cardiac tamponade from an infusion of total parenteral nutrition through an indwelling central venous catheter. The infant survived as a result of early diagnosis and aggressive therapeutic intervention. Cardiac tamponade secondary to central venous catheterisation is rare, but potentially lethal. Possible mechanisms are direct puncture by the catheter tip, or osmotic injury from the use of hypertonic solutions. To avoid this complication, the catheter tip should be prevented from entering the right atrium and its position should be checked periodically by chest X ray. Cardiac tamponade should be considered in any patient with a central venous catheter whose clinical condition deteriorates suddenly. Diagnostic or therapeutic pericardiocentesis should be employed as the first measure and time should not be wasted on other diagnostic procedures.

A new method of veno-venous bypass during human orthotopic liver transplantation

Veno-venous bypass is commonly used during orthotopic liver transplantation, but there is some controversy as to whether it contributes to a better outcome. Low shunt flows frequently reduce the efficacy of portofemoro-axillary systems and so a percutaneous cannulation technique for the subclavian and femoral vein with large bore catheters was developed in order to facilitate bypass management. This study reports the performance and complications of a portofemoro-subclavian bypass system during the anhepatic phase of human orthotopic liver transplantation in 85 patients. A percutaneous cannulation technique and two 7 mm (subclavian and femoral) catheters, inserted pre-operatively, were used in a pump driven portofemoro-subclavian bypass system. Coagulation profiles, shunt flows, haemodynamic parameters, and peri-operative complications associated with bypass were recorded for each patient. Percutaneous cannulation of the left femoral and subclavian vein was successful in 78 patients (91.8%). Mean femoro-subclavian shunt flow was 1.45 l.min-1 (SD 0.37), and mean portofemoro-subclavian flow was 4.28 l.min-1 (SD 1.03). Although oxygen delivery was not maintained at pre-shunt levels (559.7 (SD 147) vs 506 (SD 107) ml.min-1.m-2, p < 0.05) renal perfusion pressure stayed above 50 mmHg (during shunt it was 56 (SD 9) mmHg). One intra-operative air embolism was observed (1.2%), and in one patient a myocardial infarction occurred during the anhepatic phase; neither complication was considered to be related to the percutaneous cannulation technique. There were no bleeding complications. After operation, all chest X rays were normal and clinical examination revealed no adverse effects of portofemoro-subclavian bypass.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular erosion by central venous catheters. Clinical features and outcome

We evaluated the clinical characteristics of eight patients who presented with vascular erosion from central venous catheters and reviewed the available literature. Patients typically presented with dyspnea or chest pain, unilateral or bilateral pleural effusions, and mediastinal widening one to seven days after catheter insertion. Pleural fluid appeared transudative with variable glucose concentrations (range, 174 to 588 mg/dl) that were always greater than concurrent serum values. Diagnosis was delayed 3.0 +/- 1.5 days (range, 0 to 11 days) after vascular erosion. One patient died and four patients received chest tubes. Seven of eight patients had left-sided line placement; six of these seven left-sided catheters abutted the superior vena cava wall within approximately 45 degrees of perpendicular. Results of a literature search confirm the hazards of delayed diagnosis and the importance of left-sided catheter placement as a risk factor for vascular erosion.

[Cardiac tamponade and central venous catheterization]

A 32-year-old female patient was operated on for a residual colonic stricture occurring after hemicolectomy. A right internal jugular central venous catheter was inserted during the anaesthetic for postoperative parenteral feeding. The anaesthetic combined both general and epidural anaesthesia, the latter being continued for postoperative analgesia (10 ml.h-1 of 0.125% bupivacaine). Two days later, the patient complained of sudden chest pain, with restlessness, tachycardia, cyanosis, resulting in ventricular tachycardia and cardiac arrest. When admitted to the surgical intensive care unit, the patient was in deep coma and had nonsustained ventricular tachycardia, a left haemopneumothorax and a pneumopericardium. The patient died before a definitive diagnosis was made. Postmortem examination revealed an ulcerated anterior pillar of the tricuspid valve, as well as a perforation of the right ventricle and a communication between the pericardium and the left pleural cavity. The diagnosis and treatment of this rare life-threatening complication may be very difficult. It prevention consists in using short catheters for internal jugular venous access, and checking the tip's position radiologically by opacifying the catheter.