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Intubation problems due to fiberoptic bronchoscope defect
Letters to the Editor
cancer pain. However, in experimental animal models, the newer antiepileptic drugs seem superior to the established antiepileptics.12 Lamotrigine, felbamate, and gabapentin could reverse allodynia in the chronic constriction injury model, whereas carbamazepine and phenytoin were ineffective.12 This case report confirms earlier findings. Lamotrigine is a valuable co-analgesic in the treatment of neuropathic cancer pain. Jacques E. R. Devulder, MD, PhD Professor of Anesthesia Department of Anesthesia—Section Pain Clinic University of Gent Gent, Belgium
Figure 1. Double kink at 27 and 30 cm in the bronchoscope’s trunk.
References 1. Arner S, Meyerson B: Lack of analgesic effect of opioids on neuropathic and idiopathic forms of pain. Pain 1988;33:11–23. 2. McCormack K: Neuropathic pain. Pain Rev 1999;6:99 –133. 3. World Health Organization: Cancer Pain Relief, 2d ed. Geneva: WHO, 1996:74. 4. Ahmedzai S: New approaches to pain control in patients with cancer. Eur J Cancer 1997;33(Suppl):8 –14. 5. Teoh H, Fowler L, Bowery N: Effect of lamotrigine on the electrically evoked release of endogenous amino acids from slices of dorsal horn of the rat cord. Neuropharmacology 1995;34:1273– 8. 6. Boyce S, Webb J, O’Donnell R, et al: Selective NMDA NR2B antagonists induce antinociception without motor dysfunction: correlation with restricted localisation of NR2B subunit in dorsal horn. Neuropharmacology 1999;38:611–23. 7. Wang M, Offord J, Oxender D, Su T: Structural requirement of the calcium-channel subunit alpha 2 delta for gabapentin binding. Biochem J 1999;342:313–20. 8. Ocana M, Del Pozo E, Barrios M, Baeyens J: Subgroups among -opioid receptor agonists distinguished by ATP-sensitive K channel-acting drugs. Br J Pharmacol 1995;114:1296 –302. 9. Grunze H, von Wegener J, Green R, Walden J: Modulation of calcium and potassium currents by lamotrigine. Neuropsychobiology 1998;38:131– 8. 10. White H: Comparative anticonvulsant and mechanistic profile of the established and newer antiepileptic drugs. Epilepsia 1999; 40(Suppl 5):S2–10. 11. Deffois A, Fage D, Caster C: The inhibition of synaptosomal veratridine-induced sodium influx by antidepressants and neuroleptics used in chronic pain. Neurosci Lett 1996;220:117–20. 12. Hunter J, Gogas K, Jacobson L, Kassotakis L, Thompson J, Fontana D: The effect of novel anti-epileptic drugs in rat experimental models of acute and chronic pain. Eur J Pharmacol 1997;324:153– 60. PII S0952-8180(00)00215-4
Intubation Problems due to Fiberoptic Bronchoscope Defect To the Editor: We perform fiberoptically guided tracheal intubations frequently in our head and neck surgical unit, and we consider ourselves experts in the technique of awake intubation.1 The fiberoptic bronchoscope that we routinely use is the small diameter Pentax, FI 13 P, 4 mm (Tokyo, Japan). However, recently, we have experienced
difficulty with one of our bronchoscopes, even in despite of excellent quality of vision. The endotracheal tube enters the esophagus, even when there is good visualization of the carina and despite optimization of the nasopharyngeal and laryngeal axes.2,3 After some study, we found the reason behind our intubation problems, and we would like to share our experience with others. The particular fiberoptic bronchoscope concerned was found to have two small weak points at 27 and 30 cm (probably caused by accidents during manipulation), which had decreased the natural rigidity of the fiberoptic trunk without altering the quality of vision. With this defect present, when the carina was visualized through the optic eye and when the endotracheal tube was advanced, the tube kinked the trunk of the bronchoscope at the 30 cm weak point, ws not able to enter the trachea, instead guiding with its natural curve, 3 cm of the bronchoscope (located between 27 and 30 cm) into the hypopharynx and the esophagus while the tip of the endoscope remained in the trachea. This siutation results in an inability to insert the tube into the trachea or to remove the bronchoscope’s trunk from the tube.3 It was rather difficult to identify the source of our intubation problems for several reasons: Although there were some black dots in the bronchoscope’s field of vision, these did not impair visibility. Because there was no obvious damage at the above-mentioned weak point of the bronchoscope’s trunk, we did not immediately question the integrity of the device. However, a careful examination of the bronchoscope showed that a smooth pressure applied at the vertical axes of the fiberoptic trunk provoked a double kink at 27 and 30 cm which did not allow the passage of the tube over the bronchoscope (Figure 1). Performing fiberoptically guided tracheal intubations with material that is functioning at a suboptimal level can be very risky indeed. Yet it is also true that these bronchoscopes are particularly expensive, and it is not realistic to imagine that they should be readily replaced by a new device as soon as a few black dots appear in the field of vision. We recommend therefore and this particularly for small diameter bronchoscopes, careful and regular verification not only of the optical quality, but of the rigidity of the fiberoptic trunk. If such defect is found, we recomJ. Clin. Anesth., vol. 12, November 2000
575
Letters to the Editor
mend sending the concerned fiberoptic bronchoscope for repair immediately before it is used again. Lionel Dumont, MD Resident Christopher Lysakowski, MD Resident Edomer Tassonyi, MD, PhD Me´decin Adjoint. Charge´ de cours Division of Anaesthesiology Department APSIC Geneva University Hospital Geneva, Switzerland
576
J. Clin. Anesth., vol. 12, November 2000
References 1. Tassonyi E, Lehmann C, Gunning K, Coquoz E, Montandon D: Fiberoptically guided intubation in children with gangrenous stomatitis (noma). Anesthesiology 1990;73:348 –9. 2. Katsnelson T, Frost EA, Farcon E, Goldiner PL: When the endotracheal tube will not pass over the flexible fiberoptic bronchoscope [Letter]. Anesthesiology 1992;76:151–2. 3. Moorthy SS, Dierdorf SF: An unusual difficulty in fiberoptic intubation [Letter]. Anesthesiology 1985;63:229.
PIIS9052-8180(00)00205-1
cancer pain. However, in experimental animal models, the newer antiepileptic drugs seem superior to the established antiepileptics.12 Lamotrigine, felbamate, and gabapentin could reverse allodynia in the chronic constriction injury model, whereas carbamazepine and phenytoin were ineffective.12 This case report confirms earlier findings. Lamotrigine is a valuable co-analgesic in the treatment of neuropathic cancer pain. Jacques E. R. Devulder, MD, PhD Professor of Anesthesia Department of Anesthesia—Section Pain Clinic University of Gent Gent, Belgium
Figure 1. Double kink at 27 and 30 cm in the bronchoscope’s trunk.
References 1. Arner S, Meyerson B: Lack of analgesic effect of opioids on neuropathic and idiopathic forms of pain. Pain 1988;33:11–23. 2. McCormack K: Neuropathic pain. Pain Rev 1999;6:99 –133. 3. World Health Organization: Cancer Pain Relief, 2d ed. Geneva: WHO, 1996:74. 4. Ahmedzai S: New approaches to pain control in patients with cancer. Eur J Cancer 1997;33(Suppl):8 –14. 5. Teoh H, Fowler L, Bowery N: Effect of lamotrigine on the electrically evoked release of endogenous amino acids from slices of dorsal horn of the rat cord. Neuropharmacology 1995;34:1273– 8. 6. Boyce S, Webb J, O’Donnell R, et al: Selective NMDA NR2B antagonists induce antinociception without motor dysfunction: correlation with restricted localisation of NR2B subunit in dorsal horn. Neuropharmacology 1999;38:611–23. 7. Wang M, Offord J, Oxender D, Su T: Structural requirement of the calcium-channel subunit alpha 2 delta for gabapentin binding. Biochem J 1999;342:313–20. 8. Ocana M, Del Pozo E, Barrios M, Baeyens J: Subgroups among -opioid receptor agonists distinguished by ATP-sensitive K channel-acting drugs. Br J Pharmacol 1995;114:1296 –302. 9. Grunze H, von Wegener J, Green R, Walden J: Modulation of calcium and potassium currents by lamotrigine. Neuropsychobiology 1998;38:131– 8. 10. White H: Comparative anticonvulsant and mechanistic profile of the established and newer antiepileptic drugs. Epilepsia 1999; 40(Suppl 5):S2–10. 11. Deffois A, Fage D, Caster C: The inhibition of synaptosomal veratridine-induced sodium influx by antidepressants and neuroleptics used in chronic pain. Neurosci Lett 1996;220:117–20. 12. Hunter J, Gogas K, Jacobson L, Kassotakis L, Thompson J, Fontana D: The effect of novel anti-epileptic drugs in rat experimental models of acute and chronic pain. Eur J Pharmacol 1997;324:153– 60. PII S0952-8180(00)00215-4
Intubation Problems due to Fiberoptic Bronchoscope Defect To the Editor: We perform fiberoptically guided tracheal intubations frequently in our head and neck surgical unit, and we consider ourselves experts in the technique of awake intubation.1 The fiberoptic bronchoscope that we routinely use is the small diameter Pentax, FI 13 P, 4 mm (Tokyo, Japan). However, recently, we have experienced
difficulty with one of our bronchoscopes, even in despite of excellent quality of vision. The endotracheal tube enters the esophagus, even when there is good visualization of the carina and despite optimization of the nasopharyngeal and laryngeal axes.2,3 After some study, we found the reason behind our intubation problems, and we would like to share our experience with others. The particular fiberoptic bronchoscope concerned was found to have two small weak points at 27 and 30 cm (probably caused by accidents during manipulation), which had decreased the natural rigidity of the fiberoptic trunk without altering the quality of vision. With this defect present, when the carina was visualized through the optic eye and when the endotracheal tube was advanced, the tube kinked the trunk of the bronchoscope at the 30 cm weak point, ws not able to enter the trachea, instead guiding with its natural curve, 3 cm of the bronchoscope (located between 27 and 30 cm) into the hypopharynx and the esophagus while the tip of the endoscope remained in the trachea. This siutation results in an inability to insert the tube into the trachea or to remove the bronchoscope’s trunk from the tube.3 It was rather difficult to identify the source of our intubation problems for several reasons: Although there were some black dots in the bronchoscope’s field of vision, these did not impair visibility. Because there was no obvious damage at the above-mentioned weak point of the bronchoscope’s trunk, we did not immediately question the integrity of the device. However, a careful examination of the bronchoscope showed that a smooth pressure applied at the vertical axes of the fiberoptic trunk provoked a double kink at 27 and 30 cm which did not allow the passage of the tube over the bronchoscope (Figure 1). Performing fiberoptically guided tracheal intubations with material that is functioning at a suboptimal level can be very risky indeed. Yet it is also true that these bronchoscopes are particularly expensive, and it is not realistic to imagine that they should be readily replaced by a new device as soon as a few black dots appear in the field of vision. We recommend therefore and this particularly for small diameter bronchoscopes, careful and regular verification not only of the optical quality, but of the rigidity of the fiberoptic trunk. If such defect is found, we recomJ. Clin. Anesth., vol. 12, November 2000
575
Letters to the Editor
mend sending the concerned fiberoptic bronchoscope for repair immediately before it is used again. Lionel Dumont, MD Resident Christopher Lysakowski, MD Resident Edomer Tassonyi, MD, PhD Me´decin Adjoint. Charge´ de cours Division of Anaesthesiology Department APSIC Geneva University Hospital Geneva, Switzerland
576
J. Clin. Anesth., vol. 12, November 2000
References 1. Tassonyi E, Lehmann C, Gunning K, Coquoz E, Montandon D: Fiberoptically guided intubation in children with gangrenous stomatitis (noma). Anesthesiology 1990;73:348 –9. 2. Katsnelson T, Frost EA, Farcon E, Goldiner PL: When the endotracheal tube will not pass over the flexible fiberoptic bronchoscope [Letter]. Anesthesiology 1992;76:151–2. 3. Moorthy SS, Dierdorf SF: An unusual difficulty in fiberoptic intubation [Letter]. Anesthesiology 1985;63:229.
PIIS9052-8180(00)00205-1