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Awake fibre optic intubation in a 38-week pregnant patient with submandibular abscess
CASE REPORT Awake fibre optic intubation in a 3&week pregnant patient with submandibular abscess S. S. Fayek, P. A. Isaac, J. Shah Anaesthetic Department, National Guard King Khalid Hospital, Jeddah, Saudi Arabia S UMMA R Y. A 3&week pregnant patient with trismus required surgery for drainage of a submandibular abscess. Her anaesthetic management involved an awake fibre optic intubation. We describe below the details of this and discuss the options for management of similar patients.
A diagnosis of submandibular abscess was made and the patient was scheduled for urgent surgical incision and drainage of the abscess.
The use of the flexible fibre optic bronchoscope to facilitate tracheal intubation in awake patients has been well described.lm3 It is of particular use when traditional methods of tracheal intubation have failed or are not feasible due to abnormal anatomy or pathology.4 The obstetric population has a relatively higher incidence of difficulty with intubation, with failed intubation reported as great as 1 in 300.5 This is 8 times the rate of failed intubation in the general surgical population.4 A computer literature search (‘Medline’, 1984 to date) revealed only one other report of awake fibre optic intubation in a full term pregnant patient.6
ANAESTHEI’IC TECHNIQUE In view of the anticipated difficulty in endotracheal intubation and the need to protect the airway from aspiration of gastric contents it was decided that awake fibre optic intubation would be the safest technique to control the airway. The patient was premeditated with ranitidine 150 mg orally 2 h preoperatively and pethidine 75 mg and atropine 0.6 mg intramuscularly 1 h preoperatively. In the operating room she was positioned with left lateral tilt. Arterial pressure, ECG and pulse oximetry were monitored. A midwife monitored the fetal heart intermittently using a Doppler Sonicaid. An intravenous cannula was inserted and the patient was given midazolam increments of 1 mg (3 mg total). A 1% ephedrine solution was dripped into each nostril and the oropharynx and nasal mucosa were sprayed with 10% lignocaine from a metered dose spray (total approximately 60 mg). Oxygen was introduced into the left nostril through a soft suction catheter at a rate of 2 litres per min. A small nasopharyngeal airway, liberally lubricated with 2% lignocaine gel, was passed through the right nostril and left undisturbed for 5 min. A size 6 mm i.d. cuffed Portex nasotracheal tube was threaded over the fibre optic bronchoscope (4 mm diameter Olympus LF-1) and attached to the proximal end of the scope using adhesive tape. After removing the nasal airway the bronchoscope was advanced through the right nostril. The pharynx appeared mildly inflamed but no
CASE HISTORY A 32-year-old Saudi patient, 38-weeks pregnant, was admitted as an emergency. She was complaining of facial pain and swelling of 4 days duration which had become progressively worse and was creating difficulty with swallowing. On examination she had bilateral tender submandibular swelling, fluctuant on the right side, with associated submandibular and upper neck oedema. Her mouth opening was limited to 2 cm and the pharynx could not be visualised. The trachea was central and the neck extension was normal. There was a carious right second molar tooth in the lower jaw. An ultrasound scan of the submandibular region showed swelling of both submandibular glands, more extensive on the right side. S. S.
Fayek MBBCH, FRCA, P. A. Isaac MBBS, FRCA, J. Shah MD, FFARCSI, Anaesthetic Department, National Guard King
Khalid Hospital. P.O. Box 9515, Jeddah 21423, Saudi Arabia. Correspondence to Samia S. Fayek, Consultant Anaesthetist, Birmingham Heartlands Hospital, Bordesley Green East (East Birmingham Hospital), Birmingham B9 5SS, UK. 103
104 International Journal of Obstetric Anesthesia
swelling was present. The larynx was seen to be normal. Two ml of 4% lignocaine were sprayed through the bronchoscope onto the vocal cords. The tip of the bronchoscope was advanced between the cords to lie in the mid-tracheal region and the tracheal tube was advanced over the bronchoscope into the trachea. After confirmation of tube position using auscultation and end-tidal CO2 monitoring, general anaesthesia was induced with thiopentone, fentanyl and alcuronium. The total time taken to secure the airway and induce general anaesthesia was approximately 20 min. Anaesthesia was maintained with isoflurane l-2% in nitrous oxide 66%. Blood pressure and pulse were stable and oxygen saturation was 99-100% throughout the procedure. After incision and drainage of the submandibular abscess and extraction of the second lower molar, mouth opening was reassessed while the patient was still anaesthetised. The tip of the epiglottis could be visualised on direct laryngoscopy using a Macintosh size 3 blade. The patient was extubated once she was awake, and made a good recovery. Ten days later the patient was re-admitted in labour. The baby developed fetal distress and caesarean section was indicated. The anaesthetic assessment of the patient revealed that the submandibular swelling had subsided almost completely and mouth opening was normal. Rapid sequence induction with cricoid pressure, followed by tracheal intubation using conventional direct laryngoscopy, was completed successfully and caesarean section was performed. One week later the mother and baby were discharged in good condition.
DISCUSSION The use of fibre optic intubation in this patient allowed successful and safe tracheal intubation. The different options for management of difficult airway problems are well described by Cobley & Vaughan.7 This patient presented two major problems. Firstly, she had limited mouth opening because of oral pathology, and secondly because of her advanced state of pregnancy she presented a very real risk of aspiration of gastric contents. The incidence of difficulty with intubation is higher in obstetric patients than the general population.4S5*8 The traditional rapid sequence induction followed by intubation used in obstetric patients was not considered safe in this patient because of her limited mouth opening and because of difficulty in applying successful cricoid pressure in the presence of substantial neck swelling. We considered awake blind nasal tracheal intubation but rejected this as a first choice because the extent of the pathology was uncertain and also because of the potential risk of bleeding from the oropharyngeal mucosa in a near term
pregnant patient. For the latter considerations, the fibre optic bronchoscope was initially advanced into the oropharynx to assess the upper airway before introducing the endotracheal tube. Both the oral and nasal routes of fibre optic intubation have been described, but in this patient the use of the nasal route was essential because of oral pathology. In discussion with the surgeon before proceeding with the fibre optic approach, it was decided that if this was not possible because of extensive oropharyngeal pathology the chance of success with a subsequent blind nasal approach would be very small and potentially hazardous, and therefore, a tracheostomy performed under infiltration local anaesthesia would be indicated. Additional investigations which could have been useful in assessing the extent of the pathology and the airway are cervical radiographs and CT scan. Their omission did not ultimately affect the management of this patient, but in a future similar situation we would recommend their use. A sedative premeditation together with a drying agent is a key to the success of awake fibre optic intubation. Because this patient was not planned for delivery at the same time as the surgery we felt it was acceptable to use pethidine and atropine for premeditation, and midazolam increments during the procedure. Application of topical vasoconstrictor to the nasal mucosa facilitates this technique and reduces trauma to the mucosa. Cocaine has been used before with good results.7 However, it is not available in our hospital. Systemic use of ephedrine for treatment of sympathetic blockade-induced hypotension has been recognised as superior to phenylephrine in pregnancy, with a sparing effect on the uteroplacental circulation.“*” On this basis ephedrine, which is often used as a nasal decongestant, would seem to be an acceptable drug for topical use in pregnancy. We believe that important contributing factors to the successful awake fibre optic-aided intubation of this patient were careful explanation of the procedure to the patient, appropriate use of sedation, a drying agent and topical vasoconstrictor, and operator experience.
References 1. Ovassapian A, Krejcie T C, Yelich S J, Dykes M H M. Awake fibreoptic intubation in the patient at high risk of aspiration. Br J Anaesth 1989; 62: 13-16. 2. Sutherland A D, Sale J P. Fibreoptic awake intubation - a method of topical anaesthesia and of orotracheal intubation. Can Anaesth Sot J 1986; 33: 502-504. 3. Telford R J, Liban J B. Awake fibreoptic intubation. Br J Hosp Med 1991; 46: 182-184. 4. Ring T A, Adams A P. Failed tracheal intubation. Br J Anaesth 1990; 65: 400414. 5. Lyons G. Failed intubation. Six years’ experience in
Awake fibre optic intubation in a 38-week pregnant patient with submandibular abscess teaching maternity unit. Anaesthesia 1985; 40: 1599762. 6. Bums A M, Dorje P. Lawes E G, Nielsen M S. Anaesthetic management of caesarean section for a mother with pre-eclampsia, the Klippel-Feil syndrome and congenital hydrocephalus. Br J Anaesth 1988; 61: 350-354. 7. Cobley M, Vaughan R S. Recognition and management of difficult airway problems. Br J Anaesth 1992, 68: 90-97. 8. Department of Health and Social Services. Report on
health and social subjects: Reports on confidential enquiries into maternal deaths in England and Wales 1982-1984. London: HMSO, 1985. 9. Alahuhta S, Rasanen J, Jouppila P, Jouppila R. Hollmen A I. Ephedrine and phenylephrine for avoiding maternal hypotension due to spinal anaesthesia for caesarean section. International Journal of Obstetric Anesthesia 1992; 1: 1299134. 10. Tong C, Eisenach J C. The vascular mechanism of ephedrine’s beneficial effect on uterine perfusion during pregnancy. Anesthesiology 1992: 76: 792-798.
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A diagnosis of submandibular abscess was made and the patient was scheduled for urgent surgical incision and drainage of the abscess.
The use of the flexible fibre optic bronchoscope to facilitate tracheal intubation in awake patients has been well described.lm3 It is of particular use when traditional methods of tracheal intubation have failed or are not feasible due to abnormal anatomy or pathology.4 The obstetric population has a relatively higher incidence of difficulty with intubation, with failed intubation reported as great as 1 in 300.5 This is 8 times the rate of failed intubation in the general surgical population.4 A computer literature search (‘Medline’, 1984 to date) revealed only one other report of awake fibre optic intubation in a full term pregnant patient.6
ANAESTHEI’IC TECHNIQUE In view of the anticipated difficulty in endotracheal intubation and the need to protect the airway from aspiration of gastric contents it was decided that awake fibre optic intubation would be the safest technique to control the airway. The patient was premeditated with ranitidine 150 mg orally 2 h preoperatively and pethidine 75 mg and atropine 0.6 mg intramuscularly 1 h preoperatively. In the operating room she was positioned with left lateral tilt. Arterial pressure, ECG and pulse oximetry were monitored. A midwife monitored the fetal heart intermittently using a Doppler Sonicaid. An intravenous cannula was inserted and the patient was given midazolam increments of 1 mg (3 mg total). A 1% ephedrine solution was dripped into each nostril and the oropharynx and nasal mucosa were sprayed with 10% lignocaine from a metered dose spray (total approximately 60 mg). Oxygen was introduced into the left nostril through a soft suction catheter at a rate of 2 litres per min. A small nasopharyngeal airway, liberally lubricated with 2% lignocaine gel, was passed through the right nostril and left undisturbed for 5 min. A size 6 mm i.d. cuffed Portex nasotracheal tube was threaded over the fibre optic bronchoscope (4 mm diameter Olympus LF-1) and attached to the proximal end of the scope using adhesive tape. After removing the nasal airway the bronchoscope was advanced through the right nostril. The pharynx appeared mildly inflamed but no
CASE HISTORY A 32-year-old Saudi patient, 38-weeks pregnant, was admitted as an emergency. She was complaining of facial pain and swelling of 4 days duration which had become progressively worse and was creating difficulty with swallowing. On examination she had bilateral tender submandibular swelling, fluctuant on the right side, with associated submandibular and upper neck oedema. Her mouth opening was limited to 2 cm and the pharynx could not be visualised. The trachea was central and the neck extension was normal. There was a carious right second molar tooth in the lower jaw. An ultrasound scan of the submandibular region showed swelling of both submandibular glands, more extensive on the right side. S. S.
Fayek MBBCH, FRCA, P. A. Isaac MBBS, FRCA, J. Shah MD, FFARCSI, Anaesthetic Department, National Guard King
Khalid Hospital. P.O. Box 9515, Jeddah 21423, Saudi Arabia. Correspondence to Samia S. Fayek, Consultant Anaesthetist, Birmingham Heartlands Hospital, Bordesley Green East (East Birmingham Hospital), Birmingham B9 5SS, UK. 103
104 International Journal of Obstetric Anesthesia
swelling was present. The larynx was seen to be normal. Two ml of 4% lignocaine were sprayed through the bronchoscope onto the vocal cords. The tip of the bronchoscope was advanced between the cords to lie in the mid-tracheal region and the tracheal tube was advanced over the bronchoscope into the trachea. After confirmation of tube position using auscultation and end-tidal CO2 monitoring, general anaesthesia was induced with thiopentone, fentanyl and alcuronium. The total time taken to secure the airway and induce general anaesthesia was approximately 20 min. Anaesthesia was maintained with isoflurane l-2% in nitrous oxide 66%. Blood pressure and pulse were stable and oxygen saturation was 99-100% throughout the procedure. After incision and drainage of the submandibular abscess and extraction of the second lower molar, mouth opening was reassessed while the patient was still anaesthetised. The tip of the epiglottis could be visualised on direct laryngoscopy using a Macintosh size 3 blade. The patient was extubated once she was awake, and made a good recovery. Ten days later the patient was re-admitted in labour. The baby developed fetal distress and caesarean section was indicated. The anaesthetic assessment of the patient revealed that the submandibular swelling had subsided almost completely and mouth opening was normal. Rapid sequence induction with cricoid pressure, followed by tracheal intubation using conventional direct laryngoscopy, was completed successfully and caesarean section was performed. One week later the mother and baby were discharged in good condition.
DISCUSSION The use of fibre optic intubation in this patient allowed successful and safe tracheal intubation. The different options for management of difficult airway problems are well described by Cobley & Vaughan.7 This patient presented two major problems. Firstly, she had limited mouth opening because of oral pathology, and secondly because of her advanced state of pregnancy she presented a very real risk of aspiration of gastric contents. The incidence of difficulty with intubation is higher in obstetric patients than the general population.4S5*8 The traditional rapid sequence induction followed by intubation used in obstetric patients was not considered safe in this patient because of her limited mouth opening and because of difficulty in applying successful cricoid pressure in the presence of substantial neck swelling. We considered awake blind nasal tracheal intubation but rejected this as a first choice because the extent of the pathology was uncertain and also because of the potential risk of bleeding from the oropharyngeal mucosa in a near term
pregnant patient. For the latter considerations, the fibre optic bronchoscope was initially advanced into the oropharynx to assess the upper airway before introducing the endotracheal tube. Both the oral and nasal routes of fibre optic intubation have been described, but in this patient the use of the nasal route was essential because of oral pathology. In discussion with the surgeon before proceeding with the fibre optic approach, it was decided that if this was not possible because of extensive oropharyngeal pathology the chance of success with a subsequent blind nasal approach would be very small and potentially hazardous, and therefore, a tracheostomy performed under infiltration local anaesthesia would be indicated. Additional investigations which could have been useful in assessing the extent of the pathology and the airway are cervical radiographs and CT scan. Their omission did not ultimately affect the management of this patient, but in a future similar situation we would recommend their use. A sedative premeditation together with a drying agent is a key to the success of awake fibre optic intubation. Because this patient was not planned for delivery at the same time as the surgery we felt it was acceptable to use pethidine and atropine for premeditation, and midazolam increments during the procedure. Application of topical vasoconstrictor to the nasal mucosa facilitates this technique and reduces trauma to the mucosa. Cocaine has been used before with good results.7 However, it is not available in our hospital. Systemic use of ephedrine for treatment of sympathetic blockade-induced hypotension has been recognised as superior to phenylephrine in pregnancy, with a sparing effect on the uteroplacental circulation.“*” On this basis ephedrine, which is often used as a nasal decongestant, would seem to be an acceptable drug for topical use in pregnancy. We believe that important contributing factors to the successful awake fibre optic-aided intubation of this patient were careful explanation of the procedure to the patient, appropriate use of sedation, a drying agent and topical vasoconstrictor, and operator experience.
References 1. Ovassapian A, Krejcie T C, Yelich S J, Dykes M H M. Awake fibreoptic intubation in the patient at high risk of aspiration. Br J Anaesth 1989; 62: 13-16. 2. Sutherland A D, Sale J P. Fibreoptic awake intubation - a method of topical anaesthesia and of orotracheal intubation. Can Anaesth Sot J 1986; 33: 502-504. 3. Telford R J, Liban J B. Awake fibreoptic intubation. Br J Hosp Med 1991; 46: 182-184. 4. Ring T A, Adams A P. Failed tracheal intubation. Br J Anaesth 1990; 65: 400414. 5. Lyons G. Failed intubation. Six years’ experience in
Awake fibre optic intubation in a 38-week pregnant patient with submandibular abscess teaching maternity unit. Anaesthesia 1985; 40: 1599762. 6. Bums A M, Dorje P. Lawes E G, Nielsen M S. Anaesthetic management of caesarean section for a mother with pre-eclampsia, the Klippel-Feil syndrome and congenital hydrocephalus. Br J Anaesth 1988; 61: 350-354. 7. Cobley M, Vaughan R S. Recognition and management of difficult airway problems. Br J Anaesth 1992, 68: 90-97. 8. Department of Health and Social Services. Report on
health and social subjects: Reports on confidential enquiries into maternal deaths in England and Wales 1982-1984. London: HMSO, 1985. 9. Alahuhta S, Rasanen J, Jouppila P, Jouppila R. Hollmen A I. Ephedrine and phenylephrine for avoiding maternal hypotension due to spinal anaesthesia for caesarean section. International Journal of Obstetric Anesthesia 1992; 1: 1299134. 10. Tong C, Eisenach J C. The vascular mechanism of ephedrine’s beneficial effect on uterine perfusion during pregnancy. Anesthesiology 1992: 76: 792-798.
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