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C Schummer

Publications and source records attributed to C Schummer.

At least 19 recordsLinked to original sources

[Tracheal agenesis. A rare cause of respiratory insufficiency in neonates].

Tracheal agenesis is a very rare congenital anomaly that occurs isolated or in combination with other anomalies. It presents immediately after birth with an absolute respiratory insufficiency and lack of crying. The immediate precise anatomical classification of the anomaly is crucial in order to decide if surgical therapy is possible. This report describes a newborn boy with tracheal agenesis type II. The diagnosis was confirmed by spiral computed tomography and a selection of the pictures is presented. The treatment was discontinued due to a lack of therapeutical options. Based on this case report we discuss the special situation of this rare anomaly. Interesting information on tracheal agenesis was gathered, the differential diagnosis of respiratory insufficiency of the newborn is summarised and a modified algorithm of the current newborn resuscitation guidelines of the American Heart Association is presented.

Abnormalities, Multiple↗

ECG recording of central venous catheter misplaced in inferior thyroid artery.

A 71-year-old male patient with liver metastases secondary to rectal carcinoma was scheduled for hemi-hepatectomy. Two months earlier he had undergone subtotal resection of the thyroid gland. Prior to surgery, a triple-lumen catheter and an introducer sheath were introduced into the right internal jugular vein using a landmark technique. No problems occurred during insertion of the triple-lumen catheter, but resistance was noticed during insertion of the 8.5 FG introducer sheath. After placement of the introducer sheath, intra-arterial misplacement was confirmed using a pressure transducer. The opportunity was taken to record and compare intravascular ECG by the arterial and venous catheters before removal. No difference was noticed in the P-wave patterns; both showed a marked increase. Surgical exploration of the neck, recommended by the vascular surgeon consulted, showed that the carotid artery was not injured. The introducer sheath had completely punctured the right internal jugular vein and entered the inferior thyroid artery. A thrill was felt. The management of this case is discussed, with suggestions for best practice. Intravascular ECG was unhelpful in differentiating between venous and arterial placement of the catheter.

Aged↗

[Uncorrected transposition of the great arteries and large ventricular septum defect perioperative management of a caesarean section].

Patients with congenital cyanotic heart disease are a challenge to the anaesthetist due to the individual haemodynamic characteristics. Maintaining a balance between systemic and pulmonary-vascular resistance is crucial. Here we outline the successful perioperative management of a 24-year-old female with uncorrected transposition of the great arteries (D-TGA) and large septal defect of the ventricle (functionally single ventricle). She was transferred to our perinatologic centre in the 32nd week of pregnancy with symptoms of increasing cardial insufficiency. The peripartum management was agreed upon at an interdisciplinary conference and caesarean section was performed in the 35th week of pregnancy with epidural anaesthesia and no significant problems. Due to hypercoagulability and the risk of "paradoxical" embolism, low molecular weight heparin was given for 6 weeks post partum. The infant was underweight and was admitted to the neonatal intensive care unit, where she made a satisfactory progress.

Adult↗

[Vasopressin].

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Abdomen, Acute↗

[Modified ECG-guidance for optimal central venous catheter tip positioning. A transesophageal echocardiography controlled study].

BACKGROUND: Intraatrial electrocardiography (ECG) is a well-established method for central-venous catheter (CVC) placement and an intraatrial position is assumed, when a significantly increased P-wave is registered. However, an increase in P-wave amplitude also occurs in other positions. Therefore we evaluated CVC tip positioning by means of transesophageal echocardiography (TEE) at a maximum P-wave amplitude. PATIENTS AND METHODS: In this prospective randomized study the right or left internal jugular vein was cannulated with 100 patients in each group and catheter tip positioning was guided by means of ECG. The catheter was fixed at the position of maximum P-wave amplitude and the insertion depth was registered. The relationship of the CVC tip position to the superior edge of the crista terminalis was demonstrated with the help of TEE. RESULTS: In all patients the catheter tip was found +/- 0.5 cm from the superior edge of the crista terminalis at the transition from the superior vena cava to the right atrium. On x-ray control, all catheters ran along the length of the vessel wall of the superior vena cava. CONCLUSIONS: A maximum P-wave is derived even at the entrance to the right atrium. This explains why ECG-guided CVC placement -- based on the largest P-wave amplitude -- consistently resulted in correct positioning of the CVC tip at the transition from the superior vena cava to the right atrium.

Adult↗

[Extravasal position of central venous catheters despite unsuspicious ECG-guidance].

OBJECTIVE: Does the electrocardiographic method for central venous catheter positioning distinguish between a correct intravasal and a malpositioned extravasal position? METHODS: 24 cardiac surgical patients were enrolled in this prospective observational study. In 18 patients the left, in another 6 patients the right internal jugular vein was cannulated. Using a J-wire within a triple-lumen catheter the amplitude of the P-wave was measured at 3 different intravasal sites: Intra-1: (intravasal baseline electrocardiogram), i. e. 10 cm marking of the catheter on skin level; Intra-2: clear rise of the P-wave amplitude upon further insertion of the catheter; Intra-3: maximum P-wave amplitude. At this position the control of the catheter tip was achieved by means of transoesophageal echocardiography (TOE). Intraoperatively, another J-wire within a triple-lumen catheter was placed by the heart surgeon on 3 extravasal sites and the ECG was recorded: Extra-1: extravasal at the left innominate vein above the pericardial reflection; Extra-2: extravasal on the superior vena cava below the pericardial reflection; Extra-A: extravasal on ascending aorta below the pericardial reflection. The catheter was suture fixed with its tip in position Intra-3. Post surgery a chest radiograph was taken. RESULTS: All catheter tips were visualised at the basis of the Crista terminals (border between right atrium and superior vena cava) by TOE control. The rise of the P wave amplitude at Intra-2, Extra-2 and Extra-A was highly significant compared to the base line at Intra-1 (Intra-1/Intra-2, Intra-1/Extra-2, Intra-1/Extra-A: p in each case < 0.001). The P wave amplitudes of the corresponding intra- and extravasal positions of the left innominate vein (Intra-1/Extra-1, n = 18, p = 0.096)) as well as those of the superior vena cava (Intra-2/Extra-2, n = 24, p = 0.859) did not differ. CONCLUSION: The electrocardiographic method can not differentiate between intra- and extravasal position of a central venous catheter, and thus, presumably fails to identify malpositioning as a result of vascular perforation.

Aged↗

The influence of the Univent endotracheal tube on internal jugular vein cannulation.

This prospective clinical investigation assessed the effect of placement of a Univent tube on the anatomy of the internal jugular veins and the success of cannulation of the left internal jugular vein. After obtaining informed consent, 48 adult patients were enrolled. Of these, 42 patients were eligible and were divided into two groups: Univent tube (group U, n=21) and wire enforced endotracheal tube (group C, n=21). The Univent tube group were having a left thoracotomy. Using horizontal ultrasound scans just above the thyroid gland, the internal jugular vein was visualized and measured before and after Univent placement. The number of needle passes necessary to cannulate the left internal jugular vein in the two groups was also compared. Univent tubes were associated with lateral displacement of the right carotid artery and internal jugular vein on the convex side of the Univent tube, with compression of the right internal jugular vein by the artery, resulting in a kidney-shaped cross-section of the vein. On the left (concave side of the tube), the neck was indented, the sheath of the left carotid artery was displaced medially, and the left internal jugular vein distorted to an ellipse. There was a significant increase in the lateral diameter and a decrease in the cross-sectional area of the left internal jugular vein (t-test, P < 0.05). The first attempt at cannulation of the left internal jugular vein failed significantly more often in the Univent group (13/21 vs 5/21 in group C, Chi-square 6.22, P=0.025). Cannulation of the internal jugular vein before placement of the Univent tube, or placement with ultrasound guidance is suggested.

Carotid Arteries↗

Central venous catheters--the inability of 'intra-atrial ECG' to prove adequate positioning.

BACKGROUND: The classic increase in P wave size, known as 'P-atriale', is a widely accepted criterion for determination of proper positioning of central venous catheter tips. Recent transoesophageal echocardiography (TOE) studies did not confirm intra-atrial position despite advancing the central venous catheter further than indicated by ECG guidance. We postulate that the pericardial reflection rather than the entry into the right atrium corresponds to the ECG changes. In order to test our hypothesis we sought to determine the anatomical substrate for the electrical changes in an animal study. Subsequently, a modified version of the study was undertaken in man and is also reported. METHODS: In six juvenile pigs the left external jugular vein and right carotid artery were cannulated. A triple-lumen central venous catheter was positioned by ECG guidance using a Seldinger wire as an exploring electrode. The venous and arterial catheters were suture fixed 2 cm beyond the onset of an increase in P wave size. The corresponding anatomical catheter tip position was determined by open exploration of the vessels and the heart. Subsequently the catheter tip position (during advancement) of a pulmonary artery catheter and the corresponding electrical ECG changes were examined in 10 patients during open chest cardiac surgery. RESULTS: All catheters-arterial and venous, in animals and humans-revealed an increase in size of the P wave as well as the QRS complex. All venous catheters were positioned in the superior vena cava, beyond the pericardial reflection but outside the right atrium. All arterial catheters were positioned in the ascending aorta thus also beyond the pericardial reflection. CONCLUSIONS: The start of an increase in P wave size does not correspond with the entrance of the right atrium. The anatomic equivalent for the electrophysiological changes of the ECG is the pericardial reflection. ECG guidance is unable to distinguish between venous and arterial catheter position.

Aged↗

ECG-guided central venous catheter positioning: does it detect the pericardial reflection rather than the right atrium?

BACKGROUND AND OBJECTIVE: Although electrocardiography (ECG) guidance of central venous catheters (CVCs) is traditionally thought to detect the entrance into the right atrium (RA), there is little evidence in the literature to confirm this. We previously observed a high incidence of left-sided CVCs abutting the wall of the superior vena cava (SVC), even when the catheters were advanced past the point of increased P-wave amplitude. Our hypothesis was that this ECG amplitude signal is actually detecting the pericardial reflection rather than the RA. The goal of the study was to position catheter tips under ECG guidance outside the RA. METHODS: One-hundred central venous triple-lumen catheters inserted either via the right or the left internal jugular veins, respectively, were analysed in cardiac surgical patients. The position of the catheter tip was ascertained by ECG. METHOD A: A Seldinger guide-wire in the distal lumen served as exploring electrode, the respective insertion depth was recorded. METHOD B: The middle lumen (port opening 2.5 cm from the catheter tip, thus the catheter was advanced more towards the atrium) filled with a saline 10% fluid column served as the exploring electrode, and the insertion depth was recorded again. Descriptive data are given as mean+/-standard deviation. RESULTS: On average, the catheters were advanced by the expected 2+/-0.3 cm using Method B beyond the initial insertion by Method A. All 100 CVCs were finally correctly positioned in the SVC and confirmed by transoesophageal echocardiography. When chest radiography was performed after surgery not a single catheter abutted the lateral wall of the SVC. CONCLUSION: Since both methods detected the same structure, and catheters placed by Method B did not result in intra-atrial CVC tip position, the first increase in P-wave amplitude does correspond to a structure in the SVC, most likely the pericardial reflection.

Aged↗

[Delayed onset of malignant hyperthermia crisis during a living donor liver transplantation caused by sevoflurane].

We report on a 25-year old ASA physical status I patient, who developed within 20 minutes a full-blown malignant hyperthermia (MH) in the context of a living donor liver transplantation after 180 minutes of uneventful anaesthesia. The only trigger substance applied was Sevoflurane. The patient had already received a short, uneventful anaesthesia with Isoflurane a couple of years ago. In the context of the special constellation an initial dose of Dantrolene of 10 mg/kg body weight was administered. The patient was stabilised within 30 minutes, and the enzyme levels remained low compared with other case reports. The post-operative in vitro caffeine halothane contracture testing confirmed that son and mother were susceptible to MH, contracture testing in the father was negative. All known triggers may cause life-threatening MH crisis - even after hours and after inconspicuous multiple exposures to known trigger substances. Therefore all trigger substances must be avoided in all patients susceptible to MH.

Adult↗

[On the use of ultrasound to assist central vein cannulation in Germany: a surgery of 817 departments of anesthesia].

OBJECTIVE AND METHODS: A survey on the current practice in using portable ultrasound machines to assist central vein cannulation was performed by sending a questionnaire to 817 departments of anaesthesiology and intensive care medicine in Germany. Also, incomplete questionnaires were included in the analysis. RESULTS: There was a 54 % response rate. Ultrasound guidance is used by 83 (18.7 %) departments for central vein cannulation. Of these, only 7 (8.4 %) use it routinely and 43 (51.8 %) use it when faced with a difficult vein cannulation. Only one third of the departments with ultrasound facilities are using it optimally, e. g. cannulation under ultrasound guidance. Of those units not using ultrasound for central vein cannulation, 136 (37.7 %) said it was because of lack of equipment and 199 (55.1 %) did not think that it was necessary. CONCLUSION: In Germany, placement of central venous catheters is usually based on anatomical landmarks. Every anaesthetist and intensive care physician should be able to place central venous catheters without an ultrasound device. Still there is not a doubt that ultrasound assistance is useful for beginners, in children, and when blind cannulation fails. Also in patients in whom catheterisation is likely to be difficult (e. g. patients, with previous central venous catheters, with abnormal anatomy etc.) Due to our data a promotion of ultrasound assistance seems urgently required.

Anesthesia↗

Persistent left superior vena cava and central venous catheter position: clinical impact illustrated by four cases.

Variations in the course of the blood vessels are often incidental findings during clinical examination. A persistent left superior vena cava (LSVC) is really not rare (healthy individuals, 0.3-0.5%; patients with congenital heart disease, 4%) and serious complications have been described during catheterization in adults with LSVC (shock, cardiac arrest, angina). Therefore variations of the superior vena cava should be considered, especially when central venous catheterization via the subclavian or internal jugular vein is difficult. We describe the embryogenesis and the anatomic variations of persistent LSVC. Subsequently we suggest a classification of superior vena cava according to the positioning of a central venous catheter on the chest radiograph: type I, normal anatomy; type II, only persistent left superior vena cava; type IIIa, right and left superior vena cava with connection; type IIIb, right and left superior vena cava without connection. This classification is illustrated by four clinical cases.

Adult↗

[Chylothorax after central venous catheterization. Considerations to anatomy, differential diagnosis and therapy].

The authors report on a chylothorax, a rare, although classical complication of left internal jugular vein cannulation. The anatomy of major lymphatic vessels including variations is illustrated. The mechanisms of central venous catheter associated chylothorax are discussed. Likewise described are pathophysiology, signs, clinical features, and differential diagnosis with special consideration of the triglyceride content as well as treatment options.

Aged↗

[Extravasation: a rare complication of central venous cannulation? Case report of an imminent erosion of the common carotid artery].

Extravasation is the non-intentional leakage of substances/solutions into the perivascular or subcutaneous space that can result in significant tissue damage. The extent of destruction depends on the properties of the substance, its concentration, and the amount applied. Substances known to cause severe tissue damage include certain chemotherapeutic agents, vasoactive substances, concentrated electrolytes, and other hyperosmolar solutions. Extravasation can be avoided by meticulous monitoring of venous access. When extravasation occurs, the infusion should be stopped immediately. Substances known to cause tissue damage should be removed from perivascular or subcutaneous space within 24 hours by local incision and irrigation. A delay in early treatment may necessitate more extensive surgical debridement and skin coverage operations. Since the extent of deep soft tissue damage is difficult to predict and is often underestimated, a magnetic resonance imaging should be performed before surgery. We report here on a 73-year-old patient, in whom extravasation of potassium-chloride from a dislocated multi-lumen central venous catheter led to a life-threatening skin and soft-tissue necrosis of the neck. This article provides an overview of common vesicants, theories of tissue destruction, potential risk factors, guidelines for prevention, and current treatment strategies.

Aged↗

[Pseudoaneurysm--a rare complication of internal jugular vein cannulation: two case reports in liver transplant patients].

Internal jugular vein catheterization is nowadays a routine procedure in clinical practice. Arterial puncture is the most common complication of internal jugular vein catheterization. Two cases of pseudoaneurysm formation as a complication of accidental arterial puncture in liver transplant patients with coagulopathy are presented. Punctures of the common carotid artery, thyrocervical trunk, respectively were the source for these lesions. Coagulopathy is seen as an essential factor in the formation of pseudoaneurysm. Especially in patients with coagulopathy the threshold for ultrasound guidance should be low. Under these circumstances using the external jugular vein seems to be more prudent as it eliminates the risk for arterial punctures. We illuminate the genesis, signs and symptoms, diagnosis, and therapy of pseudoaneurysm. Recommendations for risk reduction are given.

Aneurysm, False↗

Intra-atrial ECG is not a reliable method for positioning left internal jugular vein catheters.

BACKGROUND: ECG guidance is widely used for positioning central venous catheters (CVCs) in the superior vena cava. We noticed a higher incidence of a more perpendicular angle between the catheter tip and the vessel wall after left-sided ECG-guided catheter positioning. To investigate the value of left-sided ECG guidance, we performed this prospective study. METHODS: Of 114 patients, 53 were randomized to right and 61 to left internal jugular vein catheterization using a triple lumen catheter. Three methods to ascertain catheter tip position were sequentially applied in each patient, and the insertion depths (ID) obtained using each of the three methods were recorded: (i). ECG guidance with a Seldinger guide wire (ID-A); (ii). ECG guidance with saline 10% used as an exploring electrode (ID-B); (iii). from position ID-B, the catheter was rotated and advanced until all three lumina could be aspirated easily. The catheter was fixed in that position (ID-C). To determine final catheter tip position, intraoperative transoesophageal echocardiography (TOE) and a postoperative chest X-ray (CXR) were performed. RESULTS: The depth of insertion of a catheter using the three methods varied significantly in left-sided (P<0.001), but not in right-sided catheters. Forty-eight of 57 (84%) left-sided CVCs, correctly positioned according to ECG guidance, had to be advanced further to achieve free aspiration through all three lumina. By this stage, five of the catheter tips had been positioned in the upper right atrium as demonstrated by TOE. There were 13 malpositions (23%) after left-sided insertion. In nine catheter malpositions, undetected by ECG guidance, the angle between the catheter tip and the lateral wall of the superior vena cava exceeded 40 degrees on CXR. CONCLUSIONS: Intra-atrial ECG does not detect the junction between the superior vena cava and right atrium. It is not a reliable method for confirming position of left-sided CVCs. Post-procedural CXRs are recommended for left-sided, but not right-sided CVCs.

Aged↗