16
Correspondence
encountered during removal of any sheathed stylet from a tracheal tube, continuation of withdrawal of the stylet might lead to separation of the stylet sheath from the core. The stylet and tracheal tube should be withdrawn together and the intubation procedure repeated with a new stylet and tracheal tube if any incidence of difficult stylet removal is encountered.
We would like to thank the authors, and this publication, for the opportunity to reply. Marketing Manager Portex Ltd, Hythe, Kent CT2l 6JL
T . MARTIN
Laryngeal mask airway for elective tracheostomy During 3 weeks working as the anaesthetist on board the ‘Mercy Mission Ship, Anastasis’ docked in a Ghanaian port, I anaesthetised two patients with ameloblastoma (giant West African jaw tumour) for mandibulectomy and partial reconstruction. In both cases an initial elective tracheostomy under general anaesthesia was proposed, the language barrier making a local technique difficult. The first patient was a 25-year-old female who was fit apart from a large mandibular tumour filling the floor of her mouth and pushing her tongue upwards and backwards. After premedication with diazepam 10 mg, an inhalational induction with halothane in oxygen was performed. The larynx could not be visualised by direct laryngoscopy. Fibreoptic equipment was unavailable, and as the anaesthetist did not consider himself adept at atraumatic blind nasal intubation, a size 3 laryngeal mask airway (LMA) was passed with ease.
As the correct position of the LMA is supraglottic, it did not need to be moved before insertion of the tracheostomy tube; the anaesthetic tubing was easily disconnected and reattached via a sterile catheter mount. The LMA was removed after the procedure had been completed. For the second patient, in spite of a visible larynx, the laryngeal mask was used in preference to a tracheal tube, as less anaesthetic manipulation was required, which was especially useful in the very cramped confines of a converted ship’s cabin operating room. Another example perhaps of using one’s ‘Brain’.
Heatherwood Hospital, Ascot. Berks SLS
K.D. THOMSON
A problem with a laryngeal mask airway We wish to report a case in which a Brain Laryngeal Mask Airway separated into two pieces upon its removal from a patient. The size 3 LMA had been inserted without difficulty in a 29-year-old male to provide a secure airway during routine varicose vein surgery. The patient was not observed to be biting on the LMA at any time during the procedure, and no tooth marks were discovered on subsequent inspection of the LMA. The LMA was removed without excessive force, when it was noticed that the tube had sheared into two separate pieces, (Fig. 1) the smaller of which had remained in the pharynx. The patient was sufficiently recovered to obey commands and the remainder of the LMA was retrieved using the pilot tube which remained intact and connected to the cuff. A further sheared area was then discovered on the tube, but this had not separated. The LMA had been in use for less than 2 months, and had always been cleansed in accordance with the manufacturer’s instructions. We have found it impossible to mark the LMA indellibly to denote the number of autoclave cycles which it has undergone. No abnormality had been detected during pre-insertion inspection of the LMA.
Fig. 1.
Our patient came to no harm as a result of this, but in other circumstances, a critical incident could havc occurred. Hairmyres Hospital, East Kilbride, Glasgow G75 8RC
M. CRAWFORD G. DAVIDSON
A reply The incident reported by D r Crawford and Dr Davidson was brought to our attention on the 1 1 April 1991. The LMA in question was returned to our manufacturers for analysis. Their reply was summarised as follows: ‘The brittleness/cracking is typical of the degradative effects on hard silicone rubbers arising from severe heat ageing’. There is no process during manufacture where this would occur. We appreciate that all efforts were made by the hospital to clean and maintain the mask correctly and cannot therefore say for certain what happened to affect this particular LMA. The hospital has since been visited by a member of Colgate Medical Ltd to offer advice where necessary on care of the LMA and recommended pre-usage checks. It is strongly felt that this is vital. Careful inspection by anaesthetic assistants prior to use should detect most problems. This is the only reported incidence of its kind in the UK in an estimated 200000 uses of the LMA. lntavent International S.A. have had no such similar occurrence in world-wide usage. However. this does highlight that we can never be too vigilant and are therefore grateful to the doctors at Hairmyres Hospital for ’winging this to our attention. Intavent Ltd. Reading, Berks
K. WOODS
Correspondence
encountered during removal of any sheathed stylet from a tracheal tube, continuation of withdrawal of the stylet might lead to separation of the stylet sheath from the core. The stylet and tracheal tube should be withdrawn together and the intubation procedure repeated with a new stylet and tracheal tube if any incidence of difficult stylet removal is encountered.
We would like to thank the authors, and this publication, for the opportunity to reply. Marketing Manager Portex Ltd, Hythe, Kent CT2l 6JL
T . MARTIN
Laryngeal mask airway for elective tracheostomy During 3 weeks working as the anaesthetist on board the ‘Mercy Mission Ship, Anastasis’ docked in a Ghanaian port, I anaesthetised two patients with ameloblastoma (giant West African jaw tumour) for mandibulectomy and partial reconstruction. In both cases an initial elective tracheostomy under general anaesthesia was proposed, the language barrier making a local technique difficult. The first patient was a 25-year-old female who was fit apart from a large mandibular tumour filling the floor of her mouth and pushing her tongue upwards and backwards. After premedication with diazepam 10 mg, an inhalational induction with halothane in oxygen was performed. The larynx could not be visualised by direct laryngoscopy. Fibreoptic equipment was unavailable, and as the anaesthetist did not consider himself adept at atraumatic blind nasal intubation, a size 3 laryngeal mask airway (LMA) was passed with ease.
As the correct position of the LMA is supraglottic, it did not need to be moved before insertion of the tracheostomy tube; the anaesthetic tubing was easily disconnected and reattached via a sterile catheter mount. The LMA was removed after the procedure had been completed. For the second patient, in spite of a visible larynx, the laryngeal mask was used in preference to a tracheal tube, as less anaesthetic manipulation was required, which was especially useful in the very cramped confines of a converted ship’s cabin operating room. Another example perhaps of using one’s ‘Brain’.
Heatherwood Hospital, Ascot. Berks SLS
K.D. THOMSON
A problem with a laryngeal mask airway We wish to report a case in which a Brain Laryngeal Mask Airway separated into two pieces upon its removal from a patient. The size 3 LMA had been inserted without difficulty in a 29-year-old male to provide a secure airway during routine varicose vein surgery. The patient was not observed to be biting on the LMA at any time during the procedure, and no tooth marks were discovered on subsequent inspection of the LMA. The LMA was removed without excessive force, when it was noticed that the tube had sheared into two separate pieces, (Fig. 1) the smaller of which had remained in the pharynx. The patient was sufficiently recovered to obey commands and the remainder of the LMA was retrieved using the pilot tube which remained intact and connected to the cuff. A further sheared area was then discovered on the tube, but this had not separated. The LMA had been in use for less than 2 months, and had always been cleansed in accordance with the manufacturer’s instructions. We have found it impossible to mark the LMA indellibly to denote the number of autoclave cycles which it has undergone. No abnormality had been detected during pre-insertion inspection of the LMA.
Fig. 1.
Our patient came to no harm as a result of this, but in other circumstances, a critical incident could havc occurred. Hairmyres Hospital, East Kilbride, Glasgow G75 8RC
M. CRAWFORD G. DAVIDSON
A reply The incident reported by D r Crawford and Dr Davidson was brought to our attention on the 1 1 April 1991. The LMA in question was returned to our manufacturers for analysis. Their reply was summarised as follows: ‘The brittleness/cracking is typical of the degradative effects on hard silicone rubbers arising from severe heat ageing’. There is no process during manufacture where this would occur. We appreciate that all efforts were made by the hospital to clean and maintain the mask correctly and cannot therefore say for certain what happened to affect this particular LMA. The hospital has since been visited by a member of Colgate Medical Ltd to offer advice where necessary on care of the LMA and recommended pre-usage checks. It is strongly felt that this is vital. Careful inspection by anaesthetic assistants prior to use should detect most problems. This is the only reported incidence of its kind in the UK in an estimated 200000 uses of the LMA. lntavent International S.A. have had no such similar occurrence in world-wide usage. However. this does highlight that we can never be too vigilant and are therefore grateful to the doctors at Hairmyres Hospital for ’winging this to our attention. Intavent Ltd. Reading, Berks
K. WOODS
