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To present a case of difficult intubation with brainstem anaesthesia after retrobulbar block with bupivacaine and lidocaine and sedation with midazolam and to point out that dose monitoring and timely treatment is important in preventing an unfavourable outcome. An 82-yr-old man with treated hypertension and stable angina was scheduled for cataract extraction. Physical examination revealed a class 2 airway. He had a retrobulbar block after topical tetracaine drops, with bupivacaine 0.5% and lidocaine 2% with hyaluronidase under sedation with 1 mg midazolam. Five minutes after the block, respiration slowed, he became unresponsive and oxygen saturation decreased to 80%. Immediate ventilation with mask without additional oxygen improved saturation. Attempted tracheal intubation failed: the epiglottis could not be visualized despite flaccid jaw and extremeties. A laryngeal mask airway was placed which was leaking and adequate ventilation could not be achieved but a second laryngeal mask airway was placed successfully. This case emphasizes the need for dose monitoring and personnel capable of managing the difficult airway when intra-orbital anaesthesia is used.

Background There is no consensus about the best way to teach fiberoptic intubation. This study assesses the effectiveness of a training program in which novice anesthetic residents routinely were taught fiberoptic tracheal intubation of anesthetized, paralyzed, apneic patients. Methods Eight inexperienced anesthetic residents learned fiberoptic and conventional tracheal intubation simultaneously during their first 4 months of training. All intubations were performed using general anesthesia and muscle paralysis. Of these intubations, 223 (23%) were fiberoptic and 743 (77%) were laryngoscopic. Subsequently, their intubation skills with the two techniques were studied in a prospective, single-blind randomized trial involving 131 elective patients. Intubation times, SpO2, ETCO2, hemodynamic changes on intubation, and complications were recorded for 71 fiberoptic and 57 laryngoscopic intubations. Results There were two failures of the rigid and one failure of the fiberoptic technique due to inability to intubate within 180 s. In cases of failure, the tracheas were intubated successfully after mask ventilation by the alterative technique. No hypoxemia or hypercarbia occurred in any patient. There were no differences in hemodynamic indexes nor incidence of sore throat or hoarseness between the two groups. Mean intubation times were 56 +/- 24 s (mean +/- SD) for fiberoptic and 34 +/- 10 s (mean +/- SD) for laryngoscopic (P < 0.001). Conclusions Novices taught fiberoptic intubation and rigid laryngoscopic intubation under similar conditions, with similar volumes of experience, learn both techniques well. The safety and effectiveness of this training regimen commend it for inclusion in any residency program.

Four case histories are presented to illustrate that haemodynamic monitoring is a useful guide in the acute management of severe pre-eclampsia and eclampsia. The application of intensive monitoring and therapy to patients in the delivery room is both feasible and of great help to the clinician managing fluid therapy and/or anaesthesia.

A solution of 1.5 gm thiopentone and 0.2 gm lidocaine in 500 cc normal saline was used successfully as the general anaesthetic for pneumoencaphalography in 23 consecutive, unselected patients. The depth of anaesthesia was effectively controlled by regulating the rate of infusion of this intravenous solution. Spontaneous respirations were adequate, blood pressures were well maintained and no arrhythmias were recorded during the procedures, despite the extreme positional changes to which the patients were subjected. The technique was assessed with continuous monitoring of arterial blood pressure, lumbar cerebro-spinal fluid pressure, respirations, electrocardiogram, arterial blood gases and serum drug levels of thiopentone and lidocaine. We believe the technique to be more satisfactory than other reported anaesthetic techniques for pneumoencephalography. Some observations about cerebro-spinal fluid pressures during pneumoencephalography, and their relationship to altered cerebro-spinal fluid dynamics, are also made.

This is a report of a case in which beta adrenergic blockade apparently cured a troublesome cardiac arrhythmia during moderate hypothermia. The total dose used was considerably smaller than has been reported during anaesthesia.

Arterial and central venous blood-gas and hydrogen ion status were studied in relation to anaesthesia in five patients with chronic uraemia and associated anaemia. Low central venous oxygen tension values were observed in all these patients, indicating increased oxygen extraction by the tissues. Low central venous to arterial differences in carbon-dioxide tensions were common in these patients, suggesting a high cardiac output.

A questionnaire was designed to determine the type of personnel that provide obstetrical anaesthesia care and the techniques used in the provision of this care. All seven hospitals with an obstetrical unit affiliated with the University of Toronto and seven community hospitals responded. All anaesthetics were given by physicians. Ninety-two per cent of those in University affiliated hospitals and 63 per cent of those in the community hospitals had obtained their specialty qualification. Standards for preoperative assessment and communication with the patients should be similar to those applied to patients receiving anaesthesia for other reasons. It was clear from our survey that pre-anaesthetic assessment of obstetrical patients differs from that advocated for other surgical patients. For vaginal deliveries, epidural analgesia was clearly the preferred choice, Subarachnoid block was rarely used. The majority of anaesthetists did not use a test dose. Eleven per cent in University-affiliated hospitals and 50 per cent in community hospitals sometimes conducted surgical anaesthesia without tracheal intubation for vaginal delivery. More than 60 per cent routinely encouraged their patients to accept general anaesthesia for Caesarean section. The doctors providing neonatal resuscitation may require further training. Surveys such as this are important if standards of anaesthetic practice are to be established.

The effect of lateral positioning and the volume of drug injected on the spread of epidural anaesthesia was assessed in 131 healthy parturients. Epidural injection for anaesthesia was done at the L3-4 interspace and a catheter was inserted into the epidural space after injection of the drug. The patients were randomly assigned to four groups. The doses used were 12 ml of bupivacaine 0.25 per cent and 6 ml of bupivacaine 0.5 per cent. Patients were kept in the lateral position in which the block was done (Groups I and III) or turned to the opposite side after completion of the epidural injection (Groups II and IV). Sensory levels and maternal assessment of pain relief were determined fifteen to twenty minutes after injection. All assessments were done by a trained observer who did not know to what group the patient had been allocated. Maintenance of the lateral position after induction of epidural anaesthesia is compatible with satisfactory analgesia for labour. Twelve ml bupivacaine 0.25 per cent provides better analgesia than 6 ml bupivacaine 0.5 per cent although the same mass is injected. The quality of analgesia is improved by turning the patients to the contralateral side after injection of 12 ml bupivacaine 0.25 per cent.

The authors studied the effectiveness of ephedrine given intramuscularly before epidural anaesthesia with bupivacaine 0.5 per cent in three groups of patients undergoing elective caesarean section. The patients received intramuscular saline as a placebo, ephedrine 25 mg or ephedrine 50 mg, 15 to 30 minutes before anaesthesia. The incidence of hypotension was 8 to 12 per cent in all three groups. Prophylactic intramuscular ephedrine did not lower the incidence of hypotension significantly. Intramuscular ephedrine 50 mg caused a persistent hypertension in eight out of 12 patients and was associated with an increase in umbilical artery [H+] (decrease in pH). No differences were observed in other indices of neonatal well-being. The prophylactic use of intramuscular ephedrine before epidural anaesthesia for caesarean section is not recommended.

The effect of lateral positioning and the volume of drug injected on the spread of epidural anaesthesia was assessed in 131 healthy parturients.