Christoph Schelenz

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OBJECTIVES The quadratic phase-coupling (QPC) within burst patterns during electroencephalic burst suppression has been quantified. METHODS It can be shown that a QPC exists between the frequency ranges 0-2.5 and 3-7.5 Hz and between the frequency ranges 0-2.5 and 8-12 Hz. By means of time-variant bicoherence analysis, a strong phase-locking between the(More)
Low-frequency (0.5–2.5 Hz) and individually defined high-frequency (7–11 or 8–12 Hz; 11–15 or 14–18 Hz) oscillatory components of the electroencephalogram (EEG) burst activity derived from thiopental-induced burst-suppression patterns (BSP) were investigated in seven sedated patients (17–26 years old) with severe head injury. The predominant high-frequency(More)
BACKGROUND The efficacy of transoesophageal echocardiography (TEE) has been evaluated predominantly in medical and cardiac surgical ICUs. This article reviews the pertinent literature and evaluates the impact of TEE in a general surgical ICU. METHODS Twenty studies on TEE in the ICU were evaluated for complications, indications, diagnostic, therapeutic,(More)
The EEG during basic sedation and burst patterns during electroencephalic burst-suppression patterns (BSP) were analyzed. The aim of EEG analysis was the characterization and quantification of the interrelations between distinct frequency components in both states of sedation. The data for the investigations were derived from the routine EEG derivations of(More)
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(More)
Time-variant partial directed coherence (tvPDC) is used for the first time in a multivariate analysis of heart rate variability (HRV), respiratory movements (RMs) and (systolic) arterial blood pressure. It is shown that respiration-related HRV components which also occur at other frequencies besides the RM frequency (= respiratory sinus arrhythmia, RSA) can(More)
OBJECTIVES Electroencephalographic burst activity characteristic of burst-suppression pattern (BSP) in sedated patients and of burst-interburst pattern (BIP) in the quiet sleep of healthy neonates have similar linear and non-linear signal properties. Strong interrelations between a slow frequency component and rhythmic, spindle-like activities with higher(More)
BACKGROUND Management of cardiac surgery patients is a very standardized procedure in respective local institutions. Yet only very limited evidence exists concerning optimal indication, safety and efficacy of hemodynamic monitoring catecholamine and fluid therapy. METHODS Between April and May 2013, all 81 German anaesthesia departments involved in(More)
Editor’s key points † It is recommended that ultrasound (US) is used to facilitate cannulation of the internal jugular vein (IJV). † This observational cohort study compared pre-procedural US with landmark techniques for IJV cannulation under general anaesthesia. † Pre-procedural US was associated with higher success rates, shorter cannulation times, and(More)
Totally implanted venous access devices (VADs) are an alternative to central line placement for those patients requiring frequent intravenous access. Venous thrombosis, infection, extrusion, extravasation and occlusion are commonly encountered complications of central VADS. Fracture with embolization of implantable venous access catheter is a rare(More)