[Reconstruction of the examination of the laryngeal carcinoma of Emperor Frederick III by Rudolf Virchow]. / Rekonstruktion der Befundung des Larynxkarzinoms Kaiser Friedrichs III. durch Rudolf Virchow.

Rudolf Virchow is one of the founders of modern pathology, and many of his ideas on inflammatory and neoplastic diseases are still valid today. Even for Virchow, determination of malignancy was not always easy. As an example, the laryngeal disease of Crown Prince Frederick William, the later Emperor Frederick III, is presented.The clinical findings at the beginning of the disease were suggestive of a carcinoma, though an inflammatory lesion was also discussed. Several attempts were made to remove the lesion bioptically, but local recurrences occurred and the first tissue samples were not examined histopathologically. Since laryngeal tumour operations had a high mortality at that time, histopathologic examinations were made in order to decide for or against an operation. The samples taken after pre-treatment did not meet Virchow's criteria for determining a carcinoma. Contrary to the present concept of a carcinoma in situ-carcinoma sequence, Virchow's concept was based on the assumption that carcinomas are not derived from the epithelium, but arise from a mesenchymal-epithelial transformation from the connective tissue. The clinical suspicion of a laryngeal carcinoma was confirmed only shortly before the patient's death and later by a post-mortem examination.The question repeatedly asked is whether Virchow should have diagnosed a carcinoma at the beginning of the disease. The answer has been the same for more than a hundred years: the clinician is dissatisfied with the histopathological diagnosis, so the pathologist is to blame.

The intubation scoop (i-scoop) - a new type of laryngoscope for difficult and normal airways.

The i-scoop is an intubation device with a curved guiding bar with laterally located lenses at its tip, rather than a blade. Twenty-five anaesthesiologists intubated a manikin that simulated first a normal and then a difficult airway. All participants were able to intubate the difficult airway with a good view of the glottis using the i-scoop. None was able to intubate using seven other laryngoscopes (Macintosh laryngoscope, GlideScope(®) GVL and AVL, McGrath(®) (Series 5/MAC), C-MAC(®) , A.P. Advance(™) ). Intubation was successful only with the Airtraq(®) (n = 10), the Airway Scope (n = 5), the C-MAC D-Blade (n = 2), the A.P. Advance DAB (n = 1) and the GlideScope DL Trainer (n = 1) (p < 0.001, success rate of i-scoop vs all 12 laryngoscopes combined). In contrast to all other videolaryngoscopes, intubation of the normal airway with the i-scoop was achieved even faster than with the Macintosh laryngoscope (p < 0.02). The i-scoop outperformed all other laryngoscopes in both difficult and normal airways, and therefore has potential as an easier and safer alternative to present devices.

Propofol, remifentanil and mivacurium: fast track surgery with poor intubating conditions.

BACKGROUND: Mivacurium is widespread used because it is the non-depolarizing muscle relaxant with the shortest duration time. Therefore, it seems to be ideal for fast track or ambulatory surgery. However, especially in combination with propofol and remifentanil onset time remains unclear and incidence of poor intubating conditions seems to be higher than in other regimes of anesthesia. METHODS: We included 35 ear, nose and throat (ENT) patients in this study. Muscle relaxation was measured by acceleromyograhpy at the adductor pollicis muscle (a.p.m.) and intubating conditions were evaluated. Anesthesia was induced with 2.5 mg kg-1 propofol and 1 µg kg-1 remifentanil and intubation was performed three minutes after the administration of 0.2 mg kg-1 mivacurium. Open vocal cords conjoined with full relaxation of the a.p.m., easy mouth opening and prevention of coughing and bucking represented the primary endpoint in this study. RESULTS: Only 20% of patients (N.=7) had optimal intubating conditions and achieved the primary endpoint. In 21 patients (60%) a complete block of the a.p.m. could not be achieved and in six patients (17%) the vocal cords were closed. In seven patients (20%) we observed difficult mouth opening and in 11 patients (31%) coughing and bucking. In addition, we found a prolonged onset time of 228±95 seconds (mean±SD). CONCLUSION: In combination with propofol and remifentanil the muscle relaxant agent mivacurium led to uncertain muscle relaxation and to poor intubating conditions. Therefore the study was aborted after 35 patients. Probably mivacurium is not a useful muscle relaxant agent if fast and deep muscle relaxation is needed. The advantage of a short duration time is foiled by intubation complications due to insufficient muscle relaxation.

Effect of ethanol on cardiac single sodium channel gating.

Alcohol in modest and higher doses has the potential to induce cardiac arrhythmias. The most famous alcohol-related arrhythmia is the "holiday heart syndrome". Furthermore, there is a clear association between excessive alcohol consumption and the risk of sudden cardiac death. However, the acute effects of ethanol on arrhythmia induction are not well understood. The effect of ethanol on single cardiac sodium channels has not been studied yet. To elucidate the effect of ethanol on human cardiac sodium channels we performed a patch clamp study in HEK-293 cells overexpressing the human cardiac sodium channel. We used HEK-293 cells overexpressing the human cardiac sodium channel (Na(1.5)). Single channel gating was investigated by the cell-attached patch clamp technique. Sodium channel currents were elicited by depolarizing pulses from -120 to -20mV for a duration of 150ms. Single channel availability, open probability and peak average current were assessed baseline and after addition of ethanol in increasing concentrations (0.50 per thousand (10.9mM), 1.00 per thousand (21.7mM), 2.00 per thousand (43.5mM) and 4.00 per thousand (87.0mM)). We found a concentration-dependent reduction of open probability which was statistically significant at 2.00 per thousand ethanol (66.5+/-14% of control). At higher concentrations (4.00 per thousand) also availability decreased to 66.5+/-11.0% of control. This resulted in a significant decrease of peak average current at 2.00 per thousand and at 4.00 per thousand ethanol (61.8+/-7.4 and 53.0+/-8.2% of control). For the first time the present study demonstrates acute inhibitory effects of ethanol on single cardiac sodium channel gating and provides one potential mechanism for the well known clinical observation that ethanol triggers supraventricular and ventricular arrhythmias.

Repeatability of measurements of the initial distribution volume of glucose in haemodynamically stable patients.

AIMS: The initial distribution volume of glucose (IDVG) has been proposed to provide a useful tool to estimate the central extracellular fluid volume. The purpose of this study was to determine the repetition interval of two consecutive measurements in haemodynamically stable patients without presence of recent changes in fluid status. METHODS: Twenty-nine patients admitted to the general intensive care unit of the University of Hirosaki Hospital were entered into this study. After achieving a haemodynamically stable state in each patient regardless of an infusion of vasoactive drugs, two glucose challenges at an interval of either 30 or 60 min, were carried out to calculate the IDVG. The IDVG was calculated using a one-compartment model after intravenous administration of glucose (5 g) followed by serial arterial blood sampling. RESULTS: Although plasma glucose levels immediately before the second glucose challenge in either group were increased compared with those of the first challenge (P < 0.001, respectively), the bias of the IDVG measurements was 0.08 +/- 0.32 L (SD) for the 30-min group and -0.19 +/- 0.28 L for the 60-min group. CONCLUSIONS: Our results indicate that IDVG determinations can be reliably repeated within a minimum interval of 30 min.

[EasyScope - an alternative to the conventional Macintosh laryngoscope?]. / Das EasyScope - Eine Alternative zum bewährten Macintosh-Laryngoskop?

OBJECTIVE: This study was conducted to compare two different techniques used for tracheal intubation (TI). We evaluated airway management conditions for a conventional Macintosh laryngoscope and the Brummert EasyScope, a new device. METHODS: A prospective trial was conducted with 20 medical students who had no prior airway management experience. Intubation was performed on an Ambu manikin. Following didactic instruction, each participant took turns performing TI using the Macintosh and EasyScope devices under direct supervision. Time required for TI, the number of attempts, and the number of times teeth were contacted were documented for each device. All participants also completed a questionnaire to determine self-assessed comfort and skill level for both the Macintosh and EasyScope devices. RESULTS: Time required for TI was comparable for both devices, although a trend toward slightly lower times for the EasyScope was observed. There was a lower rate of tooth contact during laryngoscopy and a lower rate of unsuccessful intubation attempts while using the EasyScope. Furthermore, the students felt the EasyScope was subjectively easier to use and required less effort during TI when compared with the Macintosh laryngoscope. CONCLUSION: Personnel not accustomed to a particular airway management technique achieved comparable outcomes when using either the Macintosh laryngoscope or the EasyScope device for TI. Possible reduction of effort required for tracheal intubation or better dental protection have to be evaluated for the EasyScope in further clinical studies.

[Cricothyroidotomy training on cadavers - experiences in the education of medical students, anaesthetists, and emergency physicians]. / Koniotomieübungen an der Leiche - Erfahrungen in der Ausbildung mit Medizinstudenten, Anästhesisten und Notärzten.

OBJECTIVE: Should the technique of surgical cricothyroidotomy be practiced on cadavers and should it be a compulsory part of the teaching curriculum? Is it wise to use a speculum for the insertion of the endotracheal tube? What is the optimum size of the tube? METHODS: A surgical cricothyroidotomy with a speculum was carried out on 30 cadavers from the Institute of Legal Medicine, Medical School Hannover. This took place as part of a official and voluntary course for students of advanced semesters, anaesthetists and emergency doctors with the subjects "cricothyroidotomy, chest drainage and venous cut-down". The surgical cricothyroidotomy without the use of a speculum was carried out on 5 cadavers by two clinicians well practiced in this technique. The elapsed time between skin incision and the insertion of the endotracheal tube was measured on all five subjects. After the course the participants were asked if they were able to carry out a cricothyroidotomy in an emergency. They were also asked whether this course should be a compulsory part of their curriculum and whether practical sessions should take place. During autopsies at the Institute of Legal Medicine the length of the ligamentum conicum was measured on 40 corpses with reclined and non-reclined heads. RESULTS: The average time of storage of the cadavers was 4.2 days +/- 1.9 days. The cricothyroidotomy was possible on all 35 cadavers. In one case (3,3 %) the result was a complete rupture of the cricoid cartilage. In 5 cases (16.7 %) the horizontal incision was torn due to prising with the speculum. Difficult situations always occured when the skin incision was not exactly in the midline. The average time to place the endotracheal tube into the trachea by the surgical procedure of cricothyroidotomy was 22.4 seconds +/- 3.1 seconds (minimum 18 seconds, maximum 26 seconds). 10 % of the medical students and 50 % of the anaesthetists and emergency doctors felt they would be prepared to carry out a cricothyroidotomy in an emergency. 90 % of the students and respectively 80 % of the anaesthetists and emergency doctors stated that they would like to practice the technique on a cadaver again. Almost all participants were of the opinion that the course should be integrated as a compulsory course in a future educational curriculum. The average distance between the thyroid cartilage and the cricoid cartilage was 9.5 mm +/- 1.9 mm with non-reclined head (minimum 6 mm, maximum 14 mm) and 11.9 mm +/- 2.5 mm with reclined head (minimum 7 mm, maximum 18 mm). The average difference of distances was 2.4 mm +/- 1.2 mm (minimum 1 mm, maximum 6 mm) in reclined and non-reclined heads. CONCLUSIONS: In our opinion it is highly recommended that the technique of cricothyroidotomy should be practiced on cadavers and that the course should become a compulsory part in a future educational curriculum. In addition the incision of the ligamentum conicum using dilators or a speculum is not to be recommended from the point of view of this study. The tracheal tube used in this study (reinforced wire tube, ID 6.0) was best suited for surgical cricothyroidotomy.

Applied anatomy of the superior vena cava-the carina as a landmark to guide central venous catheter placement.

BACKGROUND: Cardiac tamponade is a serious complication of central venous catheter (CVC) insertion. Current guidelines strongly advise that the CVC tip should be located in the superior vena cava (SVC) and outside the pericardial sac. This may be difficult to verify as the exact location of the pericardium cannot be seen on a normal chest x-ray. The carina is an alternative radiographic marker for correct CVC placement, suggested on the basis of studies of embalmed cadavers. METHODS: We set out to confirm this radiographic landmark in 39 fresh cadavers (age 58.4 (3.4) (mean and SE) yr) and to compare the results with those from ethanol-formalin-fixed cadavers. RESULTS: We found that the carina was 0.8 (0.05) cm above the pericardial sac as it transverses the SVC. In no case was the carina inferior to the pericardial reflection and our study confirmed the previous findings. All the measured distances were significantly greater in fresh cadavers. CONCLUSIONS: We confirm that the carina is a reliable, simple anatomical landmark that can be identified in vivo for the correct placement of CVCs outside the boundaries of the pericardial sac.

Evaluation of endoscopic retrograde cholangiopancreatography under conscious sedation and general anesthesia.

BACKGROUND AND STUDY AIMS: In adults, general anesthesia is usually only provided during endoscopic retrograde cholangiopancreatography (ERCP) when prior attempts using conscious sedation have failed. It was hypothesized that in our hospital, other factors might be associated with general anesthesia for ERCP. The aim of this study was therefore to assess the indications for ERCP under general anesthesia, and to evaluate the underlying diseases, type, and efficacy of ERCP under general anesthesia in comparison with conscious sedation. PATIENTS AND METHODS: We retrospectively analyzed 1,056 ERCPs that had been carried out with the patients under general anesthesia or conscious sedation. The indications for general anesthesia were recorded, and the underlying diseases, the type and success of the interventions, and the causes of premature ERCP termination in both groups were assessed. RESULTS: Eighteen percent of the ERCPs were performed under general anesthesia and 82% under conscious sedation. The indications for general anesthesia were related to the type of procedure planned (46%), premature termination of ERCP under conscious sedation (28%), and other reasons. Patients with primary sclerosing cholangitis and liver transplant recipients received general anesthesia more frequently (general anesthesia vs. conscious sedation, 36% vs. 16%, P < 0.0001 and 22% vs. 13%, P = 0.003). Conscious sedation was provided more frequently in patients with neoplasms and cholelithiasis (21% vs. 12%, P = 0.004 and 13% vs. 3%, P < 0.001). Painful dilations were performed more frequently with the patients under general anesthesia (60% vs. 19%, P < 0.001), whereas major papillotomies were preferably performed with conscious sedation (34% vs. 21%, P = 0.006). More interventions per ERCP were performed with the patient under general anesthesia compared to conscious sedation (P < 0.001), during the same time (51 +/- 28 min vs. 52 +/- 26 min, P = 0.39). With conscious sedation, the ERCP failure rate was double that with general anesthesia (7% vs. 14%, P = 0.012), mainly due to inadequate conscious sedation (61%). CONCLUSIONS: The frequent use of general anesthesia for ERCP at our institution is related to the underlying diseases, which are frequently treated with complex and painful ERCP procedures. The efficacy of ERCP with general anesthesia supports a continued preference for general anesthesia rather than conscious sedation when complex and painful interventional ERCP procedures are planned.

Multicenter experiences with a single lead electrode for dual chamber ICD systems.

Monitoring of atrial signals improves the accuracy in identifying supraventricular tachyarrhythmias to prevent inappropriate therapies in patients with implantable ICDs. Since difficulties due to the additional atrial lead were found in dual chamber ICD systems with two leads, the authors designed a single pass VDD lead for use with dual chamber ICDs. After a successful animal study, the prototype VDD lead (single coil defibrillation lead with two additional fractally coated rings for bipolar sensing in the atrium) was temporarily used in 30 patients during a German multicenter study. Atrial and ventricular signals were recorded during sinus rhythm (SR), atrial flutter, AF, and VT or VF. The implantation of the lead was successful in 27 of 30 patients. Mean atrial pacing threshold was 2.5 +/- 0.9 V/0.5 ms, mean atrial impedance was 213 +/- 31 ohms. Atrial amplitudes were greater during SR (2.7 +/- 1.6 mV) than during atrial flutter (1.46 +/- 0.3 mV, P < 0.05) or AF (0.93 +/- 0.37 mV, P < 0.01). During VF atrial "sinus" signals had significantly (P < 0.01) lower amplitudes (1.4 +/- 0.52 mV) than during SR. The mean ventricular sensing was 13.3 +/- 7.9 mV and mean ventricular impedance was 577 +/- 64 ohms. Defibrillation was successful with a 20-J shock in all patients. In addition, 99.6% of P waves could be detected in SR and 84.4% of flutter waves during atrial flutter. During AF, 56.6% of atrial signals could be detected without modification of the signal amplifier. In conclusion, a new designed VDD dual chamber lead provides stable detection of atrial and ventricular signals during SR and atrial flutter. Reliable detection of atrial signals is possible without modification of the ICD amplifier.

Identification of an autoimmune serum containing antibodies against the Barr body.

Transcriptional inactivation of one X chromosome in mammalian female somatic cells leads to condensation of the inactive X chromosome into the heterochromatic sex chromatin, or Barr body. Little is known about the molecular composition and structure of the Barr body or the mechanisms leading to its formation in female nuclei. Because human sera from patients with autoimmune diseases often contain antibodies against a variety of cellular components, we reasoned that some autoimmune sera may contain antibodies against proteins associated with the Barr body. Therefore, we screened autoimmune sera by immunofluorescence of human fibroblasts and identified one serum that immunostained a distinct nuclear structure with a size and nuclear localization consistent with the Barr body. The number of these structures was consistent with the number of Barr bodies expected in diploid female fibroblasts containing two to five X chromosomes. Immunostaining with the serum followed by fluorescence in situ hybridization with a probe against XIST RNA demonstrated that the major fluorescent signal from the autoantibody colocalized with XIST RNA. Further analysis of the serum showed that it stains human metaphase chromosomes and a nuclear structure consistent with the inactive X in female mouse fibroblasts. However, it does not exhibit localization to a Barr body-like structure in female mouse embryonic stem cells or in cells from female mouse E7.5 embryos. The lack of staining of the inactive X in cells from female E7.5 embryos suggests the antigen(s) may be involved in X inactivation at a stage subsequent to initiation of X inactivation. This demonstration of an autoantibody recognizing an antigen(s) associated with the Barr body presents a strategy for identifying molecular components of the Barr body and examining the molecular basis of X inactivation.

The carina as a landmark in central venous catheter placement.

Location of the tip of a central venous catheter (CVC) within the pericardium has been associated with potentially lethal cardiac tamponade. Because the pericardium cannot be seen on chest x-ray (CXR), an alternative radiographic marker is needed for correct placement of CVCs. The anatomy of the region was studied in 34 cadavers. The carina was a mean (SEM) distance of 0.4 (0.1) cm above the pericardial sac as it transverses the superior vena cava (SVC). In no case was the carina located below the pericardial sac. The carina is a reliable, simple anatomical landmark for the correct placement of CVCs. In almost all cases, the carina is radiologically visible even in poor quality, portable CXRs. CVC tips should be located in the SVC above the level of the carina in order to avoid cardiac tamponade.