British journal of anaesthesia
-
Review Randomized Controlled Trial
The effect of bi-level positive airway pressure mechanical ventilation on gas exchange during general anaesthesia.
Atelectasis may occur and ventilation-perfusion mismatch may increase during general anaesthesia with neuromuscular paralysis and mechanical ventilation, though preservation of some intermittent muscle contraction might mitigate this process. There is still no ideal manoeuvre to minimize such mismatch or atelectasis. Bi-level positive airway pressure (BiPAP) ventilation adjusts to extra breaths and improves gas exchange during recovery of diaphragm function after neuromuscular paralysis. We hypothesize that BiPAP ventilation may limit the development of pulmonary shunt and may improve ventilation-perfusion mismatch when compared with standard IPPV, with or without PEEP when neuromuscular paralysis has been used during surgery. ⋯ BiPAP ventilation was beneficial in decreasing ventilation-perfusion mismatch and improving oxygenation when compared with conventional IPPV (with or without PEEP).
-
Randomized Controlled Trial
Magnesium moderately decreases remifentanil dosage required for pain management after cardiac surgery.
Magnesium is a calcium and an NMDA-receptor antagonist and can modify important mechanisms of nociception. We evaluated the co-analgesic effect of magnesium in the postoperative setting after on-pump cardiac surgery. ⋯ Magnesium gluconate moderately reduced the remifentanil consumption without serious side-effects. The opioid-sparing effect of magnesium may be greater at higher pain intensities and with increased dosages.
-
Review
Tracheal tube-tip displacement in children during head-neck movement--a radiological assessment.
Aims of this study were to assess the maximum displacement of tracheal tube tip during head-neck movement in children, and to evaluate the appropriateness of the intubation depth marks on the Microcuff Paediatric Endotracheal Tube regarding the risk of inadvertent extubation and endobronchial intubation. ⋯ The intubation depth marks were appropriate to avoid inadvertent tracheal extubation and endobronchial intubation during head-neck movement in all patients. However, during head-neck extension the tracheal tube cuff may become positioned in the subglottic region and should be re-adjusted when the patient remains in this position for a longer time.
-
Randomized Controlled Trial Comparative Study
A comparison of patient-controlled subacromial and i.v. analgesia after open acromioplasty surgery.
The aim of this study was to compare three patient-controlled analgesia (PCA) techniques for pain relief after acromioplasty. These techniques included use of subacromial ropivacaine, subacromial fentanyl or i.v. fentanyl. ⋯ The PCA techniques using subacromial ropivacaine or fentanyl i.v. provided similar and adequate pain relief and minimal side-effects after open acromioplasty surgery. The PCA using subacromial fentanyl was not as effective as either subacromial ropivacaine or i.v. fentanyl.
-
Randomized Controlled Trial
The influence of xenon on regulation of the autonomic nervous system in patients at high risk of perioperative cardiac complications.
As xenon anaesthesia (XE) does not produce haemodynamic depression its use may be of benefit in patients at high risk of intraoperative haemodynamic instability and perioperative cardiac complications. XE (n=22) was compared with total i.v. anaesthesia (TIVA, n=22) for differences in autonomic regulation, peri- and postoperative performance. ⋯ XE patients demonstrated lower sympathetic and higher parasympathetic activity as compared with TIVA patients. This was reflected by significant differences in haemodynamics but did not correlate with a better postoperative outcome. Thus, it remains controversial whether XE provides benefits in high risk patients.