Anaesthesia
-
Review Meta Analysis
Use of plethysmographic variability index derived from the Massimo(®) pulse oximeter to predict fluid or preload responsiveness: a systematic review and meta-analysis.
This systematic review and meta-analysis assessed the accuracy of plethysmographic variability index derived from the Massimo(®) pulse oximeter to predict preload responsiveness in peri-operative and critically ill patients. A total of 10 studies were retrieved from the literature, involving 328 patients who met the selection criteria. ⋯ This could be explained by a lower accuracy of plethysmographic variability index in spontaneously breathing or paediatric patients and those studies that used pre-load challenges other than colloid fluid. The results indicate specific directions for future studies.
-
Randomized Controlled Trial Comparative Study
A randomised controlled trial comparing rocuronium priming, magnesium pre-treatment and a combination of the two methods.
We investigated whether magnesium sulphate combined with rocuronium priming shortens the onset of neuromuscular blockade, compared with these methods used alone. Ninety-two patients scheduled for general anaesthesia were randomly allocated to one of four groups: controls were given 0.6 mg.kg(-1) rocuronium; patients in the prime group were given 0.06 mg.kg(-1) rocuronium three minutes before a further dose of 0.54 mg.kg(-1) rocuronium; patients in the magnesium group were given an infusion of 50 mg.kg(-1) magnesium sulphate before rocuronium and patients in the magnesium and prime group were given both the magnesium sulphate and the priming dose of rocuronium. Tracheal intubation was attempted 40 s after the rocuronium injection. ⋯ No statistical difference was found for the duration of blockade. As for adverse events, a burning or heat sensation was reported in eight (35%) and six (26%) patients in the magnesium and magnesium and prime groups, respectively. The combination of magnesium sulphate and rocuronium priming accelerated the onset or neuromuscular blockade and improved rapid-sequence intubating conditions, compared with either magnesium sulphate or priming used alone.
-
Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor visibility of the needle tip and poor quantification of local anaesthetic spread. Sonoelastography based on tissue compression is a technique depicting tissue strain. Hitherto used largely for tumour diagnosis, we used it in both Thiel embalmed cadavers and two patients receiving interscalene and femoral blocks to observe changes in tissue strain during local anaesthetic injection. ⋯ Post-hoc analysis showed greater spread with 1 and 2.5 ml volumes compared with 0.25 ml. In patients, visibility of strain during injection was better with sonoelastography than with B-Mode ultrasound and showed a dose response from 1 to 5 ml volumes of local anaesthetic. Colour strain recognition using sonoelastography offers the ability to differentiate between nerve and surrounding tissue during local anaesthetic injection by improving visibility of spread (p = 0.04).
-
There has been little published work defining 'normal' thromboelastography (TEG(®) ) values in healthy parturients, and few large studies defining reference ranges for traditional coagulation tests in this patient group. Our aim was to establish peri-operative reference ranges for TEG and for standard laboratory coagulation tests in our pregnant population. Fifty healthy term parturients presenting for elective caesarean section under spinal anaesthesia had blood samples taken pre-operatively, on arrival in the recovery room and, in a subset of 33 women, 4 h after routine thromboprophylaxis with enoxaparin 40 mg. ⋯ Reference ranges for our pregnant population were established, demonstrating a hypercoagulable state in term parturients and a significant effect of enoxaparin. The standard coagulation reference ranges were within 98% of the local non-pregnant ranges. These reference ranges provide a useful comparator for peri-operative TEG and routine coagulation analysis in term parturients.