Anaesthesia and intensive care
Identification of the epidural space is often performed using the loss of resistance technique to either air or saline. We sought to investigate if the medium used affected the quality of analgesia obtained by parturients who received labour epidurals. We conducted a retrospective audit of labour epidurals performed on nulliparous parturients in our institution from May 2003 to March 2005. ⋯ However patients in the air group had a higher incidence of recurrent breakthrough pain P = 0.023). We also identified three other factors that were associated with an increased incidence of recurrent breakthrough pain; administration of pre-block oxytocin, sitting position of the parturient during the procedure and the use of intrathecal bupivacaine for induction of analgesia. Our findings suggest that a loss of resistance to air is associated with a higher incidence of recurrent breakthrough pain among parturients who received combined spinal epidural analgesia for labour than a loss of resistance to saline.
Randomized Controlled Trial
The purpose of this study was to determine if laryngoscopy using a Miller blade with a paraglossal approach would yield an improved view of the larynx compared to that obtained with a Macintosh blade using the standard approach. One-hundred and sixty-one patients, scheduled for elective surgery requiring tracheal intubation, voluntarily participated in this study. Patients were randomly assigned to one of the two groups (Miller vs. ⋯ A grade 1 Cormack and Lehane view of the larynx was obtained in 96.5% of cases in the Miller group compared with 85% in the Macintosh group (P = 0.02). Direct laryngoscopy using the Miller blade and paraglossal approach, afforded a much-improved view of the larynx in the majority of cases. For this reason trainees should learn laryngoscopy using both blades.
Randomized Controlled Trial Comparative Study
Low dose local anaesthetic and fentanyl epidural solutions are commonly 'topped-up' for urgent caesarean section. However, the block characteristics associated with newer local anaesthetics such as ropivacaine 0.75% and levobupivacaine 0.5% have not been fully determined. In a randomised double-blinded controlled clinical trial, we compared 2% lignocaine with adrenaline and fentanyl (LAF), 0.75% ropivacaine and 0.5% levobupivacaine for extension of low dose epidural analgesia for urgent caesarean section in 90 Asian parturients. ⋯ Levobupivacaine provided a longer duration of sensory block compared to LAF but a similar duration to 0.75% ropivacaine. Under the conditions of this study there was no significant difference in time to surgical readiness (defined as loss of sensation to cold to T4) between LAF, 0.75% ropivacaine and 0.5% levobupivacaine groups. Ropivacaine and levobupivacaine are suitable alternatives for extending epidural analgesia for urgent caesarean section.
The hypogastric plexus block is classically performed by a posterior approach, but there are recent reports of a computed tomography-guided anterior approach for patients who have difficult access to the hypogastric plexus by the posterior approach. We present two patients who were successfully given ultrasound-guided superior hypogastric plexus block by an anterior approach. ⋯ We believe this block can be useful in cancer patients who are having difficulty in lying prone, because it is a bedside procedure performed in the supine position and it is less time-consuming. It also avoids the radiation exposure involved with a computed tomography-guided anterior approach.
This study investigated the accuracy of a new technique for measuring cardiac output using the derivative Fick principle based on the ratio of change in the partial pressures of end-tidal and mixed expired carbon dioxide produced by short periods of partial rebreathing. A prospective clinical study involving 24 patients following cardiopulmonary bypass for coronary artery bypass grafting or valvular surgery was undertaken in the intensive care unit of a university-affiliated hospital. Haemodynamic measurements were performed after admission to the intensive care unit. ⋯ Cardiac output measurement using the new technique demonstrated a significant but consistent underestimate, with a bias of -0.60 +/- 0.87 l/min. This new adaptation of the partial rebreathing technique is reliable in measuring cardiac output in postoperative patients. Reasons for the consistent discrepancy between thermodilution and partial rebreathing techniques are discussed.