Der Anaesthesist
-
Randomized Controlled Trial Clinical Trial
[The effects of age on onset and recovery from atracurium, rocuronium and vecuronium blockade].
Elderly patients may show an age-related decline in physiologic functions, which may be responsible for the prolonged duration of some neuromuscular blocking agents. Previous studies have yielded conflicting results as to the effects of these drugs in the elderly. ⋯ This study suggests that onset time for atracurium, rocuronium and vecuronium is not age-dependent. Recovery was prolonged in the elderly for all three relaxants. This effect appears to be secondary to changes in body composition and function accompanying the aging process. Neither atracurium nor vecuronium depends significantly on the kidney for elimination, but the negative correlation between Ccr and rocuronium suggests an appreciable role for the kidney in the elimination of this relaxant. The long recovery times observed in this study could also be related to enflurane anaesthesia. We suggest that failure of EMG responses to return to baseline values during recovery from neuromuscular block may be related to age, especially for atracurium and rocuronium.
-
Randomized Controlled Trial Clinical Trial
[Movement of the temporomandibular joint during tracheal intubation].
Laryngoscopy causes temporary postoperative dysfunction of the temporomandibular joint (TMJ): during iatrogenic TMJ manipulation in anaesthetised patients, the TMJs have lost the protection afforded by the tone of the surrounding muscles. Thus far, the exact type and extent of TMJ movements have not been known. The purpose of this study was to develop a method to visualise and assess TMJ movements during intubation by means of electronic axiography, a diagnostic monitor of TMJ movements used in dentistry: registration of the hinge axis (HA) as an equivalent of the condylar paths on extra-oral sagittaly mounted, parallel plates. ⋯ MOTs and EITs were recorded and analysed with the system described and typical EIT patterns were identified: bland, clinically uneventful intubations (n = 7), massive distraction and laterotrusion of the EIT compared to the MOT (n = 24), and blocked or limited TMJ movements resulting in intubation problems (n = 1). With the method presented, TMJ movements could be visualised during endotracheal intubation for the first time. It can be used to assess techniques, routes, and instruments for intubation as well as to evaluate potential traumatising movements during endotracheal intubation.
-
Randomized Controlled Trial Clinical Trial
[Adaptive lung ventilation (AVL). Evaluation of new closed loop regulated respiration algorithm for operation in the hyperextended lateral position].
The lateral decubitus position is the standard position for nephrectomies. There is a lack of data about the effects of this extreme position upon respiratory mechanics and gas exchange. In 20 patients undergoing surgery in the nephrectomy position, we compared a new closed-loop-controlled ventilation algorithm, adaptive lung ventilation (ALV), which adapts the breathing pattern automatically, to the respiratory mechanics with conventionally controlled mandatory ventilation (CMV). ⋯ However, an adaptation to individual respiratory mechanics was clearly evident with ALV. In conclusion, we found that the effects of positioning for nephrectomy are minor and may give rise to problems only in patients with restrictive lung disease. The novel ALV controller automatically selects ventilatory parameters that are clinically sound and are better adapted to the respiratory mechanics of ventilated patients than the standardized settings of CMV are.
-
Randomized Controlled Trial Clinical Trial
[Perioperative physiological and cognitive functions following oral premedication with 3.75 mg midazolam in operations with retrobulbar anesthesia].
The number of surgical procedures performed as day surgery has significantly increased in recent years. Therefore, a safe and short postoperative recovery period has become increasingly important. The aim of the present study was to investigate perioperative cognitive and physiological function after oral premedication with low-dose midazolam (3.75 mg), especially during the postoperative period. ⋯ Oral administration of low-dose midazolam (0.049 +/- mg/kg) seems to be appropriate for premedication before ambulatory surgical procedures in elderly patients. In the interest of patient safety, standardised oral premedication with 3.75 mg midazolam may not be sufficient for some of the patients.
-
Randomized Controlled Trial Clinical Trial
[The effect of a heat and moisture exchanger (HME) on bronchial mucus transport in a closed inhalation anesthesia system].
The administration of dry anaesthetic gases for ventilation leads to morphological changes of the tracheobronchial epithelium that may cause postoperative pulmonary complications. Therefore, additional humidification with a heat and moisture exchanger (HME) is suggested for ventilation during anaesthesia, particularly when using semi-open breathing systems. Recommendations concerning the use of a HME in the semi-closed system are controversial. There are no data in the literature as to whether a HME improves mucociliary transport under these conditions. We therefore studied bronchial mucus transport velocity (BTV) with and without the use of a HME in the semi-closed circle system in humans. ⋯ BTV does not improve with the use of a HME in the semi-closed circle system with a fresh gas flow of 31. With modern anaesthesia machines lower fresh gas flows should be administered, whereby the humidity and temperature of the inspired gases are further increased.