The Feasibility of Endotracheal Intubation with Subcutaneous Dissociative Conscious Sedation versus General Anesthesia: A Prospective Randomized Trial


Despite outstanding improvements in anesthesia techniques and anesthetics, difficult airway is still a dilemma and is accompanied by morbidity and mortality. The aim of this study is to compare the feasibility of endotracheal intubation with the traditional method of general anesthesia by using muscle relaxants, and “sDCS” (Subcutaneous Dissociative Conscious Sedation) which has been recently reported as an efficient method of anesthesia with the capability of maintaining spontaneous ventilation and providing an appropriate situation for larynxgoscopy and endotracheal intubation. Material and Methods: This randomized clinical trial was conducted on 100 patients who were scheduled for elective laparotomy. Patients were randomly divided into two groups: group A and group B. In group A, patients underwent general anesthesia with thiopental sodium and relaxant. In group B, patients underwent “subcutaneous Dissociative Conscious Sedation” and received low dose subcutaneous ketamine and intravenous narcotic with no relaxant. The feasibility of direct laryngoscopy and tracheal intubation, hemodynamic changes, desaturation (SpO2 < 90%), patient cooperation, patient comfort, hallucination, nausea and vomiting, nystagmus and salivation were evaluated in two groups. Adverse events including apnea and need for positive pressure mask ventilation, additional dose of fentanyl were recorded in group B. The anesthesiologist who performed the procedure was asked about the patient calmness and cooperation during the procedure and the feasibility of laryngoscopy and tracheal intubation. The incidence of nausea and vomiting in post-operative care unit was recorded too. Results: Hemodynamic variables were comparable in two groups. No event of irreversible respiratory depression, desaturation, need for positive pressure ventilation and hallucination was observed in group B. All patients were cooperative and obedient during the laryngoscopy and tracheal intubation. The incidence of nausea was not statistically significant. The anesthesiologist was satisfied by the quality of patients cooperation for laryngoscopy in both groups. Conclusion: Subcutaneous dissociative conscious sedation is comparable with general anesthesia to provide desirable situation for laryngoscopy and tracheal intubation.

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S. Shabani, M. Javid and J. Zebardast, "The Feasibility of Endotracheal Intubation with Subcutaneous Dissociative Conscious Sedation versus General Anesthesia: A Prospective Randomized Trial," Open Journal of Anesthesiology, Vol. 4 No. 2, 2014, pp. 41-45. doi: 10.4236/ojanes.2014.42006.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] D. R. Hillman, P. R. Platt and P. R. Eastwood, “The Upper Airway during Anaesthesia,” British Journal of Anaesthesia, Vol. 91, No. 1, 2003, pp. 31-39.
[2] F. Donati, “Tracheal Intubation: Unconsciousness, Analgesia and Muscle Relaxation,” Canadian Journal of Anaesthesia, Vol. 50, No. 2, 2003, pp. 99-103.
[3] American Society of Anesthesiologists Task Force on Management of the Difficult Airway, “Practice Guidelines for the Management of the Difficult Airway: An Updated Report by the ASA Task Force on Management of the Difficult Airway,” Anesthesiology, Vol. 98, No. 5, 2003, pp. 1269-1277.
[4] R. Greif, B. M. Kleine and L. Theiler, “Awake Tracheal Intubation Using the Senascope in 13 Patients with an Anticipated Difficult Airway,” Anaesthesia, Vol. 65, No. 5, 2010, pp. 525-528.
[5] S. T. Simmons and A. R. Schleich, “Airway Regional Anesthesia for Awakefiberoptic Intubation,” Regional Anesthesia and Pain Medicine, Vol. 27, No., 2002, pp. 180-192.
[6] N. Pani and S. Kumar Rath, “Regional & Topical Anaesthesia of Upper Airways,” Indian Journal of Anaesthesia, Vol. 53, No. 6, 2009, pp. 641-648.
[7] K. A. Faccenda and B. T. Finucane, “Complications of Regional Anaesthesia: Incidence and Prevention,” Drug Safety, Vol. 24, No., 2001, pp. 413-442.
[8] K. S. Chu, F. Y. Wang, H. T. Hsu, I. C. Lu, H. M. Wang and C. J. Tsai, “The Effectiveness of Dexmedetomidine Infusion for Sedating Oral Cancer Patients Undergoing Awake Fibreoptic Nasal Intubation,” European Journal of Anaesthesiology, Vol. 27, No. 1, 2010, pp. 36-40.
[9] R. Avitsian, M. Manlapaz and J. D. Doyle, “Dexmedetomidine as a Sedative for Awakefiberoptic Intubation,” Journal of Clinical Anesthesia, Vol. 17, 2007, pp. 19-24.
[10] S. S. Moorthy, S. Gupta, B. Laurent and E. C. Weisberger, “Management of Airway in Patients with Laryngeal Tumors,” Journal of Clinical Anesthesia, Vol. 17, No. 8, 2005, pp. 604-609.
[11] G. Kim, S. M. Green, T. K. Denmark and B. Krauss, “Ventilatory Response during Dissociative Sedation in Children: A Pilot Study,” Academic Emergency Medicine, Vol. 10, No. 2, 2003, pp. 140-145.
[12] Y. C. Xu, F. S. Xue, M. P. Luo, Q. Y. Yang, X. Liao, Y. Liu and Y. M. Zhang, “Median Effective Dose of Remifentanil for Awake Laryngoscopy and Intubation,” Chinese Medical Journal, Vol. 122, No. 13, 2009, pp. 1507-1512.
[13] K. Mönkemüller, L. Zimmermann, “Propofol and Fospropofol Sedation during Bronchoscopy,” Chest, Vol. 137, No. 6, 2010, p. 1489.
[14] M. R. Rai, T. M. Parry, A. Dombrovskis and O. J. Warner, “Remifentanil Target-Controlled Infusion Vspropofoltarget Controlled Infusion for Conscious Sedation for Awake Fibreoptic Intubation: A Double-Blinded Randomized Controlled Trial,” British Journal of Anaesthesia, Vol. 100, No. 1, 2008, pp. 125-130.
[15] T. Cafiero, F. Esposito, G. Fraioli, G. Gargiulo, A. Frangiosa, L. M. Cavallo, N. Mennella and P. Cappabianca, “Remifentanil-TCI and Propofol-TCI for Conscious Sedation during Fiberoptic Intubation in the Acromegalic Patient,” European Journal of Anesthesiology, Vol. 25, No. 8, 2008, pp. 670-674.
[16] D. Stolz, P. Chhajed, J. Leuppi, M. Brutsche, E. Pflimlin and M. Tamm, “Couph Suppression during Flexible Bronchoscopy Using Combined Sedation with Midazolam and Hydrocodeine: A Randomized Double Blind Placebo Controlled Trial,” Thorax, Vol. 59, 2004, pp. 773-776.
[17] M. J. Javid, M. Rahimi and A. Keshvari, “Dissociative Conscious Sedation, an Alternative to General Anesthesia for Laparascopic Peritoneal Dialysis Catheter Implantation: A Randomized Trial Comparing Intravenous and Subcutaneous Ketamine,” Peritoneal Dialysis International, Vol. 31, No. 3, 2010, pp. 308-314.
[18] M. J. Javid, “Subcutaneous Dissociative Conscious Sedation (sDCS) an Alternative Method for Airway Regional Blocks: A New Approach,” BMC Anesthesiology, Vol. 11, 2011, p. 19.
[19] M. J. Javid, “Conscious Sedation with Subcutaneous ketamine as an Alternative to Airway Regional Blocks [Abstract],” 1st International Congress of Airway Management and Anesthesia in Head and Neck Surgery, Tehran, 20-22 May 2009, p. 131.
[20] M. J. Javid, M. B. Rahim and S. Rafiian, “Subcutaneous Dissociative Conscious Sedation (sDCS) a New Approach to Compromised Airway in Mediastinal Masses,” Open Journal of Anesthesiology, Vol. 2, No. 4, 2012, pp. 166-169.
[21] R. H. Kroneberg, “Ketamine as an Analgesic: Parentral, Oral, Rectal, Subcutaneous, Transdermal and Intranasal Administration,” Journal of Pain & Palliative Care Pharmacotherapy, Vol. 16, No. 3, 2002, pp. 27-35.
[22] A. Cromhout, “Ketamine: Its Use in the Emergency Department,” Emergency Medicine, Vol. 15, No. 2, 2003, pp. 155-159.
[23] C. M. Arroyo-Novoa, M. I. Figueroa-Ramos, C. Miaskowski, G. Padilla, S. M. Paul, P. Rodríguez-Ortiz, et al., “Efficacy of Small Doses of Ketamine With Morphine to Decrease Procedural Pain Responses During Open Wound Care,” The Clinical Journal of Pain, Vol. 27, No. 7, 2011, pp. 561-566.
[24] K. Jackson, M. Ashby, D. Howell, J. Petersen, D. Brumley and P. Good, “The Effectiveness and Adverse Effects Profile of ‘Burst’ Ketamine in Refractory Cancer Pain: The VCOG PM 1-00 Study,” Journal of Palliative Care, Vol. 26, No., 2010, pp. 176-183.
[25] M. L. Rasmussen, O. Mathiesen, G. Dierking, B. V. Christensen, K. L. Hilsted, T. K. Larsen, et al., “Multimodal Analgesia with Gabapentin, Ketamine and Dexamethasone in Combination with Paracetamol and Ketorolac after Hip Arthroplasty: A Preliminary Study,” European Journal of Anaesthesiology, Vol. 27, 2010, pp. 324-330.
[26] G. Treston, A. Bell, R. Cardwell, G. Fincher, D. Chand and G. Cashion, “What Is the Nature of the Emergence Phenomenon When Using Intravenous or Intramuscular Ketamine for Paediatric Procedural Sedation?” Emergency Medicine Australasia, Vol. 21, No. 4, 2009, pp. 315-322.
[27] N. H. Jun, J. K. Shim, Y. S. Choi, S. H. An and Y. L. Kwak, “Effect of Ketamine Pretreatment for Anaesthesia in Patients Undergoing Percutaneous Transluminal Balloon Angioplasty with Continuous Remifentanil Infusion,” Korean Journal of Anesthesiology, Vol. 61, No. 4, 2011, pp. 308-314.
[28] S. Sener, C. Eken, C. H. Schultz, M. Serinken and M. Ozsarac, “Ketamine with and without Midazolam for Emergency Department Sedation in Adults: A Randomized Controlled Trial,” Annals of Emergency Medicine, Vol. 57, No. 2, 2011, pp. 109-114.
[29] R. Kohrs, M. E. Durieux, “Ketamine: Teaching an Old Drug New Tricks,” Anesthesia & Analgesia, Vol. 87, No. 5, 1998, pp. 1186-1193.
[30] M. G. Soliman, G. F. Brinale and G. Kuster, “Response to Hypercapnia under Ketamine Anesthesia,” Canadian Anesthetists’ Society Journal, Vol. 22, No. 4, 1975, pp. 486-494.

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