Anaesthesia for ophthalmological surgery

Local anaesthetic techniques in ophthalmic surgery

This article, which won third place in the Alison Bell Writer's Award this year, reports the findings of a literature review that explored the use of local anaesthetic techniques used in ophthalmic surgery. The author describes the various ophthalmic procedures that can take place under local anaesthetic and asks whether there is a need for an anaesthetist to be present for such lists. Issues such as patient monitoring requirements and intravenous access are also discussed, emphasising the importance of the nurse's role in informing, supporting and comforting the patient through what can be a stressful experience.

Changes in intra-ocular pressure during general anaesthesia. A comparison of spontaneous breathing through a laryngeal mask with positive pressure ventilation through a tracheal tube

Changes in-intra-ocular pressure during spontaneous ventilation with a laryngeal mask were compared with controlled ventilation using a tracheal tube in 40 patients undergoing intra-ocular surgery under general anaesthesia. Intra-ocular pressure was measured before induction, after establishing the airway, at the end of the operation and after removal of the airway device. Anaesthesia was induced with propofol and maintained with enflurane and nitrous oxide in oxygen. Mean end-tidal carbon dioxide tension was significantly higher during spontaneous ventilation than during controlled ventilation 5 min after establishing the airway (5.7 versus 4.5) and at the end of surgery (6.1 versus 4.2) (p < 0.001). Despite this, intra-ocular pressures were lower than baseline and similar in the two groups throughout anaesthesia. At the end of surgery, intra-ocular pressure (mmHg) was 11.2 and 8.6 during spontaneous or controlled ventilation respectively. One min after removal of the device, mean intra-ocular pressure (mmHg) in the tracheal tube group (16.0) was slightly higher than baseline (15.3) and was significantly higher than the laryngeal mask group (10.9) (p < 0.01). Spontaneous ventilation with a laryngeal mask is an acceptable alternative to controlled ventilation with tracheal intubation in elective intra-ocular surgery.