Intra‐ocular pressure changes using the laryngeal mask airway and tracheal tube

Abstract

SummaryIntra-ocular pressure was measured before and throughout airway establishment with either the laryngeal mask airway or tracheal tube. Similar measurements were made on removal of either airway and the amount of coughing noted in thejrst minute after removal. There was a significantly smaller increase in intra-ocular pressure ( p < 0.001) using the laryngeal mask airway, both on placement and removal, than with the tracheal tube. Postoperative coughing was significantly reduced using the laryngeal mask airway ( p < 0.001). There was a significantly greater rise in heart rate using the tracheal tube ( p < 0.01) probably related to an increased cardiovascular response. The laryngeal mask airway is recommended as an alternative to tracheal intubation in routine and emergency intra-ocular surgery.

Risk of pulmonary aspiration with laryngeal mask airway and tracheal tube: analysis on 65 712 procedures with positive pressure ventilation

“…Postoperative hoarseness, sore throat, impairment of swallowing, pain, nausea and vomiting, and coughing are reduced, post-anaesthesia recovery unit length of stay is shortened, and increases in intra-ocular pressure and derangements in cardiovascular and respiratory function are less likely [1][2][3][4][5][6][7][8][9][10][11]. Furthermore, the LMA can be useful in the management of the difficult airway when facemask ventilation is inadequate [12].…”

Changes in intra–ocular pressure during general anaesthesia

“…A modified laryngeal mask with a flexo-metallic tube was first described in 1990 [14] and is now recognised as a suitable alternative to tracheal intubation in patients undergoing elective eye operations [ 151-usually with controlled ventilation [5-91. The changes in IOP in previous studies have varied with the techniques used. Some authors have shown increases after tracheal intubation [5,9,161 whereas others have shown a reduction [7]. Many authors [5,6,9,161 have shown significantly lower IOPs after insertion of a laryngeal mask compared to tracheal intubation.…”

“…Some authors have shown increases after tracheal intubation [5,9,161 whereas others have shown a reduction [7]. Many authors [5,6,9,161 have shown significantly lower IOPs after insertion of a laryngeal mask compared to tracheal intubation. Our present results showed a significant reduction in IOP after intubation in both groups compared to baseline.…”

“…At the end of the operation the laryngeal mask cuffwas deflated and the device was removed before the patient regained consciousness-this may have reduced the incidence of coughing. The laryngeal mask is associated with a much lower incidence of postoperative coughing, straining and breath holding and diminished pressure response compared to tracheal extubation [5,7,201. Brimacombe and Berry [21] have drawn attention to the need for an adequate depth of anaesthesia in patients with an 'open' eye during spontaneous ventilation through the laryngeal mask.…”

“…In recent studies where controlled ventilation only was employed , the laryngeal mask was compared to tracheal intubation for intra-ocular surgery. Although Akhtar and others [7] found that the laryngeal mask did not offer any advantages over tracheal intubation in the control of IOP, other investigators [5,6,9] have concluded that the change in IOP was less with the former device than the latter. Payne and Edwards [ 101 used fibreoptic laryngoscopy to confirm the position of the laryngeal mask; they reported that the oesophagus was clearly visible through the laryngeal mask aperture in 6% of the patients and emphasised that, in their view, this type of airway could not provide effective protection against aspiration of gastric contents.…”