Variables Influencing the Depth of Conscious Sedation in Plastic Surgery: A Prospective Study

Background Conscious sedation has been widely utilized in plastic surgery. However, inadequate research has been published evaluating adequate drug dosage and depth of sedation. In clinical practice, sedation is often inadequate or accompanied by complications when sedatives are administered according to body weight alone. The purpose of this study was to identify variables influencing the depth of sedation during conscious sedation for plastic surgery.

Methods This prospective study evaluated 97 patients who underwent plastic surgical procedures under conscious sedation. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, and glucose levels were measured. Midazolam and ketamine were administered intravenously according to a preset protocol. Bispectral index (BIS) recordings were obtained to evaluate the depth of sedation 4, 10, 15, and 20 minutes after midazolam administration. Associations between variables and the BIS were assessed using multiple regression analysis.

Results Alcohol intake and female sex were positively associated with the mean BIS (P<0.01). Age was negatively associated with the mean BIS (P<0.01). Body mass index (P=0.263), creatinine clearance (P=0.832), smoking history (P=0.398), glucose (P=0.718), AST (P=0.729), and ALT (P=0.423) were not associated with the BIS.

Conclusions Older patients tended to have a greater depth of sedation, whereas females and patients with greater alcohol intake had a shallower depth of sedation. Thus, precise dose adjustments of sedatives, accounting for not only weight but also age, sex, and alcohol consumption, are required to achieve safe, effective, and predictable conscious sedation.

Keywords

Conscious sedation - Deep sedation - Hypnotics and sedatives - Consciousness monitors

This article was presented at the Fifth Research & Reconstructive Forum on May 14, 2015 in Pyeongchang, Korea.

Publication History

Received: 13 August 2016

Accepted: 20 October 2016

Article published online:
20 April 2022

• REFERENCES

• 1 Pollock H, Forman S, Pollock T. et al. Conscious sedation/local anesthesia in the office-based surgical and procedural facility. Clin Plast Surg 2013; 40: 383-388
• 2 Li YH, He R, Ruan JG. Effect of hepatic function on the EC50 of midazolam and the BIS50 at the time of loss of consciousness. J Zhejiang Univ Sci B 2014; 15: 743-749
• 3 Yi Y, Heo D, Son HJ. et al. Association between bispectral index and age and use of sedative drugs in high spinal anaesthesia. J Int Med Res 2013; 41: 378-385
• 4 Brill MJ, Diepstraten J, van Rongen A. et al. Impact of obesity on drug metabolism and elimination in adults and children. Clin Pharmacokinet 2012; 51: 277-304
• 5 Steven RK, Catherine RM, Brian G. et al. Does alcohol consumption impact conscious sedation during endoscopy?. Gastrointest Endosc 2001; 53: AB84
• 6 Mustoe TA, Kim P, Schierle CF. Outpatient abdominoplasty under conscious sedation. Aesthet Surg J 2007; 27: 442-449
• 7 Veselis RA, Reinsel RA, Feshchenko VA. Drug-induced amnesia is a separate phenomenon from sedation: electrophysiologic evidence. Anesthesiology 2001; 95: 896-907
• 8 Rogers R, Wise RG, Painter DJ. et al. An investigation to dissociate the analgesic and anesthetic properties of ketamine using functional magnetic resonance imaging. Anesthesiology 2004; 100: 292-301
• 9 Gruber RP, Morley B. Ketamine-assisted intravenous sedation with midazolam: benefits and potential problems. Plast Reconstr Surg 1999; 104: 1823-1825
• 10 Morioka N, Ozaki M, Matsukawa T. et al. Ketamine causes a paradoxical increase in the bispectral index. Anesthesiology 1997; 87: A502
• 11 Nonaka A, Makino K, Suzuki S. et al. Low doses of ketamine have no effect on bispectral index during stable propofol-remifentanil anesthesia. Masui 2012; 61: 364-367
• 12 Glass PS, Bloom M, Kearse L. et al. Bispectral analysis measures sedation and memory effects of propofol, midazolam, isoflurane, and alfentanil in healthy volunteers. Anesthesiology 1997; 86: 836-847
• 13 Bell JK, Laasch HU, Wilbraham L. et al. Bispectral index monitoring for conscious sedation in intervention: better, safer, faster. Clin Radiol 2004; 59: 1106-1113
• 14 Pleym H, Spigset O, Kharasch ED. et al. Gender differences in drug effects: implications for anesthesiologists. Acta Anaesthesiol Scand 2003; 47: 241-259
• 15 Gan TJ, Glass PS, Sigl J. et al. Women emerge from general anesthesia with propofol/alfentanil/nitrous oxide faster than men. Anesthesiology 1999; 90: 1283-1287
• 16 Yen YH, Lin TF, Lin CJ. et al. Sex differences in conscious sedation during upper gastrointestinal panendoscopic examination. J Formos Med Assoc 2011; 110: 44-49
• 17 Katoh T, Suguro Y, Ikeda T. et al. Influence of age on awakening concentrations of sevoflurane and isoflurane. Anesth Analg 1993; 76: 348-352
• 18 Yamashita K, Terao Y, Inadomi C. et al. Age-dependent relationship between bispectral index and sedation level. J Clin Anesth 2008; 20: 492-495
• 19 Avram MJ, Fragen RJ, Caldwell NJ. Midazolam kinetics in women of two age groups. Clin Pharmacol Ther 1983; 34: 505-508
• 20 Adler M, Schaffner F. Fatty liver hepatitis and cirrhosis in obese patients. Am J Med 1979; 67: 811-816
• 21 Haeck PC, Swanson JA, Iverson RE. et al. Evidence-based patient safety advisory: patient selection and procedures in ambulatory surgery. Plast Reconstr Surg 2009; 124: 6s-27s
• 22 Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease [Internet]. New York: KDIGO; 2013. cited 2016 Nov 28 Available from:. http://www.kdigo.org/clinical_practice_guidelines/pdf/CKD/KDIGO_2012_CKD_GL.pdf
• 23 Dostalek M, Akhlaghi F, Puzanovova M. Effect of diabetes mellitus on pharmacokinetic and pharmacodynamic properties of drugs. Clin Pharmacokinet 2012; 51: 481-499
• 24 Kroon LA. Drug interactions with smoking. Am J Health Syst Pharm 2007; 64: 1917-1921
• 25 Joshi GP, Ahmad S, Riad W. et al. Selection of obese patients undergoing ambulatory surgery: a systematic review of the literature. Anesth Analg 2013; 117: 1082-1091