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B Bein

Publications and source records attributed to B Bein.

25 records · Page 2Linked to original sources

A comparison of the intubating laryngeal mask airway and the Bonfils intubation fibrescope in patients with predicted difficult airways.

Tracheal intubation with the intubating laryngeal mask airway or the Bonfils intubation fibrescope was performed in 80 patients with predicted difficult airways. Mallampati score, thyromental distance, mouth opening and mobility of the atlanto-occipital joint were used to predict difficult airways. The overall success rate, time to the first adequate lung ventilation and time taken for the successful placement of the tracheal tube were recorded, as well as a subjective assessment of the handling of the device and the incidence of postoperative sore throat and hoarseness. The median [range] time to the first adequate ventilation was significantly shorter with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (28 [6-85] s vs. 40 [23-77] s, p < 0.005). Tracheal intubation was significantly slower with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (76 [45-155] s vs. 40 [23-77] s, p < 0.0001. Patients in the Bonfils group suffered less sore throat and hoarseness than those in the other group.

Adolescent↗

Effect of xenon anaesthesia on accuracy of cardiac output measurement using partial CO2 rebreathing.

Cardiac output (CO) determination based on partial CO(2) rebreathing has recently been introduced into clinical practice. The determination of flow is crucial for exact CO readings and the physical properties of xenon, i.e. high density and viscosity, may influence flow readings. This study compared echocardiography-derived CO measurements with the partial rebreathing method during total intravenous (TIVA) vs. xenon-based anaesthesia. Thirty-nine patients ASA physical status III undergoing aortic reconstruction were randomly assigned to receive either xenon (Xe, n = 20) or TIVA (T, n = 19) based general anaesthetic. Paired measurements were taken before xenon administration, after xenon administration, before and after clamping of the abdominal aorta and after declamping and at corresponding time points in the TIVA group. Data were analysed with a Bland-Altmann plot. Bias and precision were acceptable and comparable before xenon administration (T 0.54 +/- 0.92 l.min(-1) vs. Xe 0.11 +/- 1.1 l.min(-1)), but after xenon administration CO was largely overestimated by partial CO(2) rebreathing (T 0.04 +/- 0.91 l.min(-1) vs. Xe -4.0 +/- 2.1 l.min(-1)). In the TIVA group, bias and precision after declamping increased significantly (P < 0.01) compared to all time points except baseline. In its current application, the NICO cardiac output monitor appears to be inappropriate for determination of CO during xenon based anaesthesia.

Aged↗

Tracheal intubation using the Bonfils intubation fibrescope after failed direct laryngoscopy.

Failed tracheal intubation due to a difficult airway is an important cause of anaesthetic morbidity and mortality. This study was undertaken to evaluate the effectiveness of the Bonfils intubation fibrescope for tracheal intubation after failed direct laryngoscopy. Twenty-five patients undergoing coronary artery bypass grafting were enrolled in the study after two attempts at conventional laryngoscopy by a board certified anaesthetist had failed. Intubation with the Bonfils fibrescope was successful on the first attempt in 22 patients (88%) and on the first or second attempt in 24 patients (96%); in one patient intubation was impossible. Median (IQR [range]) time to intubation using the Bonfils intubation fibrescope was 47.5 (30-80 [20-200]) s. Tracheal intubation using the Bonfils intubation fibrescope appears to be a simple and effective technique for the management of a difficult intubation.

Aged↗

[Heart rate variability in anesthesia].

Measurement of heart rate variability (HRV) in the perioperative period is not yet part of routine monitoring. Because of a lack of standardization, comparison of results of different investigations is difficult. Caution is needed in interpreting data of HRV measurements because of the complexity of autonomic control of the cardiovascular system. Moreover, confounding effects of multiple factors influencing HRV in the perioperative setting make interpretation of data difficult and limit this methodology, for example, as a depth-of-anaesthesia monitor. HRV reflects the response of the heart to a variety of influences. None of the parameters obtained, however, elucidates directly the mechanism or site of action of an anaesthetic drug. Knowledge of the pathophysiology underlying HRV is critical in order to understand the state of the autonomic nervous system and its relevance for patient management. Nevertheless, previous studies show that HRV can provide information about sympathetic and parasympathetic influences affecting the cardiovascular system in the perioperative period. Thus, HRV seems to be a useful tool for preoperative cardiovascular risk stratification. Of major concern in this context is the quality of the recording of the electrocardiogram when assessing HRV. Because of the ongoing progress in monitoring with regard to acquisition and computer-based analysis of HRV data, it seems at least possible to measure HRV routinely in the perioperative setting. However, the need for standardization requires large prospective and standardized trials. Depending on the results, the clinical relevance of HRV as a relatively simple and non-invasive perioperative monitoring has to be re-evaluated.

Anesthesia, General↗

Increased binding capacity of receptors for the epidermal growth factor in benign thyroid nodules and thyroid malignancies.

To determine the role of epidermal growth factor (EGF) receptors in thyroid tumorigenesis, EGF binding was compared in membranes from malignant and from benign thyroid tumors. Surgical specimens were obtained from 28 patients with thyroid carcinomas (3 papillary, 13 follicular, 6 undifferentiated, and 6 medullary carcinomas) and from 30 patients with benign thyroid tumors (15 scintigraphically functional and 15 nonfunctional nodules). In 30 cases normal tissue adjacent to the tumor was also obtained. EGF binding was seen to be increased not only in thyroid carcinomas but also in benign thyroid tumors, particularly in functional thyroid adenomas. The highest EGF binding was found in undifferentiated carcinomas. A direct comparison of the EGF binding characteristics in tumor and adjacent normal thyroid tissue revealed that the increased binding of EGF is due mainly to an increase in the number of binding sites rather than an alteration in receptor affinities. EGF binding capacities were 18.4 +/- 16.7 fmol/mg protein in thyroid carcinomas and 10.5 +/- 5.2 fmol/mg in the corresponding normal tissue (P < 0.05, Kd 0.84 +/- 0.26 nM, n = 11). In autonomously functioning thyroid adenomas binding capacities were 14.2 +/- 8.2 fmol/mg in the nodules and 8.9 +/- 4.8 fmol/mg in normal tissue (P < 0.01, Kd 0.73 +/- 0.62 nM, n = 15). In conclusion, EGF receptor levels are increased not only in malignant thyroid tumors but also in well-differentiated benign thyroid nodules.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Thyroid surgery according to Enderlen-Hotz or Dunhill: a comparison of two surgical methods for the treatment of Graves' disease.

The surgical therapy of Graves' disease is favored in Germany, which is an iodine-deficient area, and nodular transformation is common. The surgical methods mainly differ in their extent of resection. We examined 152 patients with regard to operative and postoperative complications in a prospective randomized study. Patients were randomized to two groups: treated either by subtotal resection on both sides (STT) or subtotal resection with contralateral hemithyroidectomy (SHT), the two most common surgical procedures. The follow-up period was 6 years; complication and recurrence rates were studied. There was no significant difference concerning mortality, recurrent laryngeal nerve palsy, hypocalcemia, secondary hemorrhage, wound infections, or recurrence rate between STT and SHT. However, SHT only requires a unilateral resection in case of a recurrence, thus reducing the risk of bilateral recurrent laryngeal nerve palsy.

Adolescent↗