Peri-operative modern goal-directed therapy reduces morbidity and mortality. Importantly, the quality of evidence was low to very low (e.g. Grading of Recommendations, Assessment, Development and Evaluation scoring), and there was much clinical heterogeneity among the goal-directed therapy devices and protocols. Additional well designed and adequately powered trials on peri-operative goal-directed therapy are necessary.

We have reviewed accidental spinal administration of tranexamic acid. We performed a MEDLINE search of cases of administration of tranexamic acid during epidural or spinal anaesthesia between 1960 and 2018. No reports of epidural administration were identified. We identified 21 cases of spinal tranexamic acid administration. Life-threatening neurological and/or cardiac complications, requiring resuscitation and/or intensive care, occurred in 20 patients; 10 patients died. We used a Human Factors Analysis Classification System model to analyse any contributing factors, and the reports were also assessed using four published recommendations for the reduction in neuraxial drug error. In 20 cases, ampoule error was the cause; in the last case a spinal catheter was mistaken for an intravenous catheter. All were classified as skill-based errors. Several human factors related to organisational policy; dispensing and storage of drugs and preparation for spinal anaesthesia tasks were present. All errors could have been prevented by implementing the four published recommendations.

SummaryPercutaneous tracheostomy is a well established technique used primarily to assist weaning from mechanical ventilation on many intensive care units. We report our experiences of a total of 36 procedures performed with the new Blue Rhinoe Percutaneous Tracheostomy Introducer Set developed by Ciaglia. The technique was successful in all cases and was simpler and quicker to perform than with the earlier Ciaglia percutaneous tracheostomy set. Difficulties were encountered when using Shileye tracheostomy tubes. Significant complications included one posterior wall tear and one tracheal cartilage ring fracture.

The QT interval, which is measured from the start of the Q wave (or the R wave when no Q wave is present) to the completion of the T wave, reflects the duration of electrical ventricular systole. The duration of systole varies with heart rate and therefore the measured QT interval is often corrected for heart rate using the following formula, in which QTc represents the rate corrected value: QTc = Qt/VRR interval The QTc interval is normally less than 440 ms [1]. Increased serum concentrations of noradrenaline and a change in the balance between sympathetic and parasympathetic tone may be associated with prolonged QT interval [2, 3]; this may be controlled with either f}-block [4] or stellate ganglion block [5]. Hypomagnesaemia and, more commonly, hypokalaemia cause clinically significant prolongation which may be produced by effects on the repolarizing potassium current. Sleep (which is associated with a reduction in sympathetic tone) prolongs QTc [6]. Induction of anaesthesia with thiopentone prolongs significantly the QT interval [7], whereas Althesin had no effect [8]. The most marked changes follow tracheal intubation facilitated with suxamethonium, but these changes may be reduced by pretreatment with tubocurarine [7] or by (3-block [9], suggesting mediation by the sympathetic nervous system. It has been reported also that the QT interval is significantly prolonged by enflurane [8, 10], but not by halothane anaesthesia [8]. The mechanism underlying these differences has not been explained. It has been reported that these volatile agents and also

SummaryThis study investigates the changes in serum magnesium levels after major gastrointestinal surgery and evaluates if Plasma -Lyte 148 used as maintenance fluid influences these changes in the peri-operative period. Thirty patients presenting for procedures ranging from anterior rectal resection to thoraco -abdominal cardio -0esophagectomy were randomly allocated into two groups, one of which received compound sodium lactate solution as the maintenance crystalloid during the intra-and postoperative period, and the other Plasma-Lyte 148, a magnesium -containing crystalloid solution. Serum magnesium levels were measured pre-operatively, in the immediate recovery period and 24 h postoperatively. The results showed a statistically signiJicant ( p < 0.05) reduction in the magnesium levels in both groups. The reduction was less marked in the Plasma-Lyte group but this did not achieve statistical significance ( p > 0.05) compared with the compound sodium lactate group.

Bilateral ilioinguinal nerve blockade was performed, using 0.5% plain bupivacaine 10 ml to each side, in 13 patients having elective Caesarean section under general anaesthesia. Pain scores and requirement for postoperative analgesia were compared with 13 patients in a control group. Pain scores were less in the block patients at all times during the first day after operation, with the exception of 12 h. There was an increased time from the patient's recovery from anaesthesia to the first injection of opioid in the block group. In the control group, patients required more analgesia in the first 24 h after surgery compared with patients having ilioinguinal nerve blockade. There were no observed adverse effects following nerve blocks.

SummaryA patient in whom vasovagal asystole was induced by the performance of a spinal anaesthetic in the upright position is described. This illustrates the importance of routine monitoring of the electrocardiograph during regional anaesthesia. The risk of vasovagal syncope may be increased by the use of the silting position and by the omission of anxiolytic premedication. Key wordsAnaesthetic techniques, regional; spinal. Complications; as ystole . Case historyA 34-year-old man presented for internal fixation of his left ankle following a fracture. He was physically fit and history and examination were unremarkable. His ankle had been manipulated under general anaesthesia 2 days previously but the fracture alignment was unsatisfactory. The patient complained of nausea after his first anaesthetic, so a spinal anaesthetic was suggested as an alternative for the second procedure. There was a full discussion of risks and side effects. No premedication was given at the patient's request.The arterial blood pressure was measured on arrival in the anaesthetic room (systolic 130 mmHg) and electrocardiograph (ECG) leads attached for continuous monitoring. After subcutaneous infiltration of 1 % lignocaine, a 16-G cannula was inserted into a vein on the left forearm and 500 ml of a crystalloid solution was infused rapidly.The patient was positioned on the trolley sitting upright with his head bent over his knees. Spinal anaesthesia was performed using an aseptic technique. Two ml 1% lignocaine were infiltrated subcutaneously over the L,-, interspace. A 25-G spinal needle was inserted through the skin and spinal ligaments at that level until clear cerebrospinal fluid (CSF) was obtained. Two and a half ml of 0.5% bupivacaine in dextrose was injected into the subarachnoid space. As the injection was being completed, the ECG trace was seen to be flat. The ECG electrodes were still attached to the patient but his eyes were closed, his breathing was stertorous and no peripheral pulse could be palpated. The needle was removed from the patient's back immediately, he was laid supine and oxygen was administered.

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