Letters to Editor
oxygen leading to wastage of gas. In our institution, the protocol is to start and adjust desired oxygen flow first then put the mask and while removing, it is to taking off the mask first then to stop flows. This technique prevents correct starting and stopping of oxygen. The auxillary oxygen supply should be included in anesthesia machine check. Akshaya N. Shetti, Vithal K. Dhulkhed, Dewan Roshansingh1, Sunil Khyadi Department of Anaesthesiology and Critical Care, Krishna Institute of Medical Sciences, Karad, Maharashtra, 1Mahatma Gandhi Medical College and Research Institute, Pondicherry, India Address for correspondence: Dr. Akshaya N. Shetti, Department of anaesthesiologyand Critical Care, Krishna Institute of Medical Sciences, Karad, Maharashtra, India. E-mail: [email protected]
Page | 303
REFERENCES 1.
2.
Association of Anaesthetists of Great Britain and Ireland (AAGBI), Hartle A, Anderson E, Bythell V, Gemmell L, Jones H, McIvor D, et al. Checking anesthetic equipment 2012: Association of anaesthetists of Great Britain and Ireland. Anesthesia 2012;67:660-8. American Society of Anesthesiologists Committee on Equipment and Facilities: Recommendations for Pre-Anesthesia Checkout Procedures, 2008. Available from: http://www. asahq.org/clinical/fda.htm. [Last accessed on 2013 Jul 26]. Access this article online Quick Response Code:
Website: www.saudija.org
DOI: 10.4103/1658-354X.130759
Defective endotracheal tube: Undetected by routine inspection Sir, Endotracheal intubation is an essential step for securing the airway of a patient. Ideally endotracheal tube (ETT) should be of appropriate size, as it acts as an extension of trachea, with added disadvantage of increased dead space, increased resistance and work of breathing.[1] The increase work of breathing is considerable in paediatric patients due to narrower airway. [2,3] Factors which determine the resistance imposed by ETT on gas flow are internal diameter, length, configuration, and dead space of the tube. According to Hagen Poiseuille law ΔP = (L × v × V)/r[4] Where ΔP is the pressure gradient across the tube, r is the radius of the tube, L is length, v is the viscosity of the gas, and V is the flow rate. American National Standards Institute/International Standards Organization had put recommendations for anesthetic and respiratory equipment — tracheal tubes and connectors (ANS/ISO 5361), including material Saudi Journal of Anesthesia
of construction, internal diameter, length, inflation system, cuff, radius of curvature, markings, packing, and labelling of ETT. Previous cases[4,5] of endotracheal tube malfunction or defects inside the tube, cuff inflation tube, or pilot valve have been reported. A 1 year old child with diagnosis of tetralogy of Fallot (TOF) with cyanotic spell was received in cardiothoracic and vascular surgery ICU for management. The oxygen saturation was not improved satisfactorily, even after administration of parenteral morphine, intravenous fluid, and noradrenaline infusion. Then plan for intubation and emergency modified Blalock — Taussig (BT) shunt was made. After administration of intravenous ketamine, atropine and suxamithonium, endotracheal intubation was performed with 4 mm uncuffed ETT(Sterimed, India). There was resistance to manual ventilation. Chest was auscultated for assessment of equal bilateral air entry, which revealed feeble breath sound. Ventilation with Jackson and Rees (JR) circuit was rechecked for tube kink or malfunction of the components, which were found to be alright. Endotracheal tube was thought to be appropriate as it had snugly passed through the vocal cord and there was no palpable or audible leak. Suspecting the presence of secretions or mucus plug a 6F suction catheter was Vol. 8, Issue 2, April-June 2014
Letters to Editor Page | 304
inserted into the ETT. Surprisingly, the catheter could not be negotiated freely beyond the ETT connector. The patient was reintubated with another 4 mm uncuffed ETT (Portex) after removing the earlier one. The air entry was adequate and equal bilaterally. Rest course of the patient during the perioperative period was uneventful. External examination of the first ETT revealed nothing, but connector of the tube revealed annular meniscus eventually creating a narrowed orifice at the patient end of the connector [Figure 1]. The machine end of the connector was absolutely normal when compared with connector of ETT of the same size [Figure 2]. Bilateral air entry was decreased due to high resistance. We suspect the ETT connector lastly after ruling out all other causes of poor air entry.
situation may occur in other hospitals also due to lack of standardization or quality control of endotracheal connector. The main learning point to be highlighted here is, in the absence of any common obvious reason (esophageal intubation, bronchospasm, kinking of ETT, secretions, tension pneumothorax, cuff herniation) for inadequate ventilation to replace the ETT after performing direct laryngoscopy and inspect both tube and connector of previous tube. Ashok K. Badamali, Bhukal Ishwar1 Assistant Professor & I/C Cardiac Anesthesia, Department of Anesthesia and Intensive Care, Hi-Tec Medical College & Hospital, Bhubaneswar, Odisha, 1Department of Anesthesia and Intensive Care, Post Graduate Institute of Medical Education & Research, Chandigarh, India
We have reported a case of defective endotracheal tube, where the problem was in the patient end of ETT connector which could not be detected even after through and repeated external examination. Such similar
Address for correspondence: Dr. Ashok Kumar Badamali, Plot no 34 (B),Ground Floor, VIP area, Nayapalli, Bhubaneswar - 751 015, Odisha, India. E-mail: [email protected]
REFERENCES 1.
2. 3.
Figure 1: Patient end of ETT connector showing meniscus
4. 5.
Bersten AD, Rutten AJ, Vedig AE, Skowronski GA. Additional work of breathing imposed by endotracheal tubes, breathing circuits, and intensive care ventilators. Crit Care Med 1989;17:671-7. Beatty PC, Healy TE. The additional work of breathing through Portex Polar “Blue Line” pre-formed pediatric tracheal tubes. Eur J Anaesthesiol 1992;9:77-83. Manczur T, Greenough A, Nicholson GP, Rafferty GF. Resistance of pediatric and neonatal endotracheal tubes: Influence of flow rate, size and shape. Crit Care Med 2000;28:1595-8. Lewer BM, Karim J, Henderson RS. Large air leak from an endotracheal tube due to a manufacturing defect. Anesth Analg 1997;85:944-5. Sofi K, El-Gammal K. Endotracheal tube defects: Hidden causes of airway obstruction. Saudi J Anaesth 2010;4:108-10. Access this article online Quick Response Code:
Website: www.saudija.org
DOI: 10.4103/1658-354X.130760
Figure 2: Machine end of ETT connector
Vol. 8, Issue 2, April-June 2014
Saudi Journal of Anesthesia
Copyright of Saudi Journal of Anaesthesia is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
oxygen leading to wastage of gas. In our institution, the protocol is to start and adjust desired oxygen flow first then put the mask and while removing, it is to taking off the mask first then to stop flows. This technique prevents correct starting and stopping of oxygen. The auxillary oxygen supply should be included in anesthesia machine check. Akshaya N. Shetti, Vithal K. Dhulkhed, Dewan Roshansingh1, Sunil Khyadi Department of Anaesthesiology and Critical Care, Krishna Institute of Medical Sciences, Karad, Maharashtra, 1Mahatma Gandhi Medical College and Research Institute, Pondicherry, India Address for correspondence: Dr. Akshaya N. Shetti, Department of anaesthesiologyand Critical Care, Krishna Institute of Medical Sciences, Karad, Maharashtra, India. E-mail: [email protected]
Page | 303
REFERENCES 1.
2.
Association of Anaesthetists of Great Britain and Ireland (AAGBI), Hartle A, Anderson E, Bythell V, Gemmell L, Jones H, McIvor D, et al. Checking anesthetic equipment 2012: Association of anaesthetists of Great Britain and Ireland. Anesthesia 2012;67:660-8. American Society of Anesthesiologists Committee on Equipment and Facilities: Recommendations for Pre-Anesthesia Checkout Procedures, 2008. Available from: http://www. asahq.org/clinical/fda.htm. [Last accessed on 2013 Jul 26]. Access this article online Quick Response Code:
Website: www.saudija.org
DOI: 10.4103/1658-354X.130759
Defective endotracheal tube: Undetected by routine inspection Sir, Endotracheal intubation is an essential step for securing the airway of a patient. Ideally endotracheal tube (ETT) should be of appropriate size, as it acts as an extension of trachea, with added disadvantage of increased dead space, increased resistance and work of breathing.[1] The increase work of breathing is considerable in paediatric patients due to narrower airway. [2,3] Factors which determine the resistance imposed by ETT on gas flow are internal diameter, length, configuration, and dead space of the tube. According to Hagen Poiseuille law ΔP = (L × v × V)/r[4] Where ΔP is the pressure gradient across the tube, r is the radius of the tube, L is length, v is the viscosity of the gas, and V is the flow rate. American National Standards Institute/International Standards Organization had put recommendations for anesthetic and respiratory equipment — tracheal tubes and connectors (ANS/ISO 5361), including material Saudi Journal of Anesthesia
of construction, internal diameter, length, inflation system, cuff, radius of curvature, markings, packing, and labelling of ETT. Previous cases[4,5] of endotracheal tube malfunction or defects inside the tube, cuff inflation tube, or pilot valve have been reported. A 1 year old child with diagnosis of tetralogy of Fallot (TOF) with cyanotic spell was received in cardiothoracic and vascular surgery ICU for management. The oxygen saturation was not improved satisfactorily, even after administration of parenteral morphine, intravenous fluid, and noradrenaline infusion. Then plan for intubation and emergency modified Blalock — Taussig (BT) shunt was made. After administration of intravenous ketamine, atropine and suxamithonium, endotracheal intubation was performed with 4 mm uncuffed ETT(Sterimed, India). There was resistance to manual ventilation. Chest was auscultated for assessment of equal bilateral air entry, which revealed feeble breath sound. Ventilation with Jackson and Rees (JR) circuit was rechecked for tube kink or malfunction of the components, which were found to be alright. Endotracheal tube was thought to be appropriate as it had snugly passed through the vocal cord and there was no palpable or audible leak. Suspecting the presence of secretions or mucus plug a 6F suction catheter was Vol. 8, Issue 2, April-June 2014
Letters to Editor Page | 304
inserted into the ETT. Surprisingly, the catheter could not be negotiated freely beyond the ETT connector. The patient was reintubated with another 4 mm uncuffed ETT (Portex) after removing the earlier one. The air entry was adequate and equal bilaterally. Rest course of the patient during the perioperative period was uneventful. External examination of the first ETT revealed nothing, but connector of the tube revealed annular meniscus eventually creating a narrowed orifice at the patient end of the connector [Figure 1]. The machine end of the connector was absolutely normal when compared with connector of ETT of the same size [Figure 2]. Bilateral air entry was decreased due to high resistance. We suspect the ETT connector lastly after ruling out all other causes of poor air entry.
situation may occur in other hospitals also due to lack of standardization or quality control of endotracheal connector. The main learning point to be highlighted here is, in the absence of any common obvious reason (esophageal intubation, bronchospasm, kinking of ETT, secretions, tension pneumothorax, cuff herniation) for inadequate ventilation to replace the ETT after performing direct laryngoscopy and inspect both tube and connector of previous tube. Ashok K. Badamali, Bhukal Ishwar1 Assistant Professor & I/C Cardiac Anesthesia, Department of Anesthesia and Intensive Care, Hi-Tec Medical College & Hospital, Bhubaneswar, Odisha, 1Department of Anesthesia and Intensive Care, Post Graduate Institute of Medical Education & Research, Chandigarh, India
We have reported a case of defective endotracheal tube, where the problem was in the patient end of ETT connector which could not be detected even after through and repeated external examination. Such similar
Address for correspondence: Dr. Ashok Kumar Badamali, Plot no 34 (B),Ground Floor, VIP area, Nayapalli, Bhubaneswar - 751 015, Odisha, India. E-mail: [email protected]
REFERENCES 1.
2. 3.
Figure 1: Patient end of ETT connector showing meniscus
4. 5.
Bersten AD, Rutten AJ, Vedig AE, Skowronski GA. Additional work of breathing imposed by endotracheal tubes, breathing circuits, and intensive care ventilators. Crit Care Med 1989;17:671-7. Beatty PC, Healy TE. The additional work of breathing through Portex Polar “Blue Line” pre-formed pediatric tracheal tubes. Eur J Anaesthesiol 1992;9:77-83. Manczur T, Greenough A, Nicholson GP, Rafferty GF. Resistance of pediatric and neonatal endotracheal tubes: Influence of flow rate, size and shape. Crit Care Med 2000;28:1595-8. Lewer BM, Karim J, Henderson RS. Large air leak from an endotracheal tube due to a manufacturing defect. Anesth Analg 1997;85:944-5. Sofi K, El-Gammal K. Endotracheal tube defects: Hidden causes of airway obstruction. Saudi J Anaesth 2010;4:108-10. Access this article online Quick Response Code:
Website: www.saudija.org
DOI: 10.4103/1658-354X.130760
Figure 2: Machine end of ETT connector
Vol. 8, Issue 2, April-June 2014
Saudi Journal of Anesthesia
Copyright of Saudi Journal of Anaesthesia is the property of Medknow Publications & Media Pvt. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
