In addition to the dropdown menu options above, we have listed below other commonly encountered patient responses, our locational assignment, and an explanation of our reasons for this approach:
Among 4692 patients, 52.7% (95% confidence interval [CI], 51.3%–54.2%) of patients had amnesia of the operating room (OR) before induction of anesthesia. With regard to the postoperative period, 94.1% (95% CI, 93.2%–94.8%) of 3411 patients had amnesia of the OR after induction of anesthesia.
At the University of Manitoba (Winnipeg) study site, 23.1% (95% CI, 19.9%–26.7%) of 589 patients had amnesia of the OR before induction of anesthesia at 1 to 3 days postoperatively. As for the postoperative period, 96.0% (95% CI, 93.8%–97.5%) of 455 patients had amnesia of the OR after induction of anesthesia at 1 to 3 days postoperatively.
At Washington University in St. Louis and the University of Chicago, midazolam was typically administered in the preoperative holding area, whereas at the University of Manitoba, midazolam was typically administered in the OR.
Dr. Franklin Dexter is the Statistical Editor and the Section Editor for Economics, Education, and Policy for Anesthesia & Analgesia. This manuscript was handled by Dr. Gregory Crosby, and Dr. Dexter was not involved in any way with the editorial process or decision.
a An extreme example illustrates the potential for amnesia to create bias in satisfaction surveys of anesthesiologists’ care. Suppose that a nurse anesthetist was in a holding area and connected a syringe with 2 mg midazolam to a patient’s IV. The patient told the nurse anesthetist that she (the patient) was not anxious and wanted to be awake when going into the OR and during the intraoperative briefing. Suppose that an anesthesiologist, who did not know the patient, walked up to the bed in the holding area and, without speaking to the nurse anesthetist or the patient, administered the midazolam in violation of the patient’s wishes. Assume that the patient had no recollection of this interaction with the anesthesiologist. Substituting complete satisfaction for this patient would result in a biased measure of satisfaction with the anesthesiologist’s care. The extreme example is not related to nonresponse, but bias. Recall is fundamental to satisfaction. Psychometrically, consider 10 patients providing a 10-point scale evaluation of satisfaction. Five of 10 patients reporting no recall of the anesthesiologist is the same as 1 student leaving 5 of 10 questions unanswered. Consider, 1 student with perfect scores on the first 5 questions and scores of 2 to 9 on the last 5 questions. The second student obtains perfect scores on the first 5 questions and skips the last 5 questions. Absence of answering the last 5 questions does not result in a greater overall score than the first student. Because the 10-point scale is arbitrary, assigning 0 to each of the skipped questions is indistinguishable from any other choice that results in a lesser overall score than the first student. That is why the routine approach of scoring an unanswered question as 0 is appropriate. Mathematically, either the patient without recall of the anesthesiologist is assigned the lowest satisfaction score or measuring satisfaction in the setting of lack of recall is invalid. Regardless of these 2 choices, suppose that at least half the patients have lack of recall. Then, the issue is moot because any overall satisfaction score would be “0” and that would apply regardless of how the test questions are combined (see http://FDshort.com/WikipediaBreakdown and http://FDshort.com/GeyerBreakdown. Accessed April 6, 2015).
b The implication of our study is not that assessments of patient satisfaction lack value. Anesthesia groups have a responsibility to be integrally involved in patient satisfaction with the perioperative period. However, that is different from assessing satisfaction with the individual anesthesiologist’s preoperative care. Interview by the anesthesiologist who will participate in the anesthetic delivery is the most important attribute of the preanesthesia visit for more than half of patients.25 From the patients’ point of view, getting to know the anesthesiologist who will deliver anesthesia is of importance to most patients25 and increases patient satisfaction.26 In many (and perhaps), most, hospitals, however, preoperative assessment of patients undergoing elective surgery is not performed by an anesthesiologist who will also provide the anesthesia care to the patient. For a survey instrument about perioperative satisfaction with an individual anesthesiologist to have face validity, it would need to include questions about preoperative assessment by the same anesthesiologist who participated in the anesthetic care. The second most important attribute from the patient perspective is the time spent waiting for the interview.25 Both patients and professionals often consider this the attribute with the greatest need for improvement.27 Consequently, this too should be included in an instrument of satisfaction with the individual anesthesiologist from the patient’s perspective.
4. Warner DO, Sun H, Harman AE, Culley DJ. Feasibility of patient and peer surveys for Maintenance of Certification among diplomates of the American Board of Anesthesiology. J Clin Anesth. 2015;27:290–5
5. Smallman B, Dexter F, Masursky D, Li F, Gorji R, George D, Epstein RH. Role of communication systems in coordinating supervising anesthesiologists’ activities outside of operating rooms. Anesth Analg. 2013;116:898–903
6. Blandford CM, Gupta BC, Montgomery J, Stocker ME. Ability of patients to retain and recall new information in the post-anaesthetic recovery period: a prospective clinical study in day surgery. Anaesthesia. 2011;66:1088–92
7. De Witte JL, Alegret C, Sessler DI, Cammu G. Preoperative alprazolam reduces anxiety in ambulatory surgery patients: a comparison with oral midazolam. Anesth Analg. 2002;95:1601–6
8. Naguib M, Samarkandi AH. Premedication with melatonin: a double-blind, placebo-controlled comparison with midazolam. Br J Anaesth. 1999;82:875–80
9. Bulach R, Myles PS, Russnak M. Double-blind randomized controlled trial to determine extent of amnesia with midazolam given immediately before general anaesthesia. Br J Anaesth. 2005;94:300–5
10. Greenblatt DJ, Abernethy DR, Locniskar A, Harmatz JS, Limjuco RA, Shader RI. Effect of age, gender, and obesity on midazolam kinetics. Anesthesiology. 1984;61:27–35
11. Pryor KO, Reinsel RA, Mehta M, Li Y, Wixted JT, Veselis RA. Visual P2-N2 complex and arousal at the time of encoding predict the time domain characteristics of amnesia for multiple intravenous anesthetic drugs in humans. Anesthesiology. 2010;113:313–26
12. Veselis RA, Reinsel RA, Feshchenko VA, Wroński M. The comparative amnestic effects of midazolam, propofol, thiopental, and fentanyl at equisedative concentrations. Anesthesiology. 1997;87:749–64
13. Davis PL, Gather U. The breakdown point—examples and counterexamples. Revstat-Stat J. 2007;5:1–17
14. Avidan MS, Zhang L, Burnside BA, Finkel KJ, Searleman AC, Selvidge JA, Saager L, Turner MS, Rao S, Bottros M, Hantler C, Jacobsohn E, Evers AS. Anesthesia awareness and the bispectral index. N Engl J Med. 2008;358:1097–108
15. Avidan MS, Jacobsohn E, Glick D, Burnside BA, Zhang L, Villafranca A, Karl L, Kamal S, Torres B, O’Connor M, Evers AS, Gradwohl S, Lin N, Palanca BJ, Mashour GABAG-RECALL Research Group. . Prevention of intraoperative awareness in a high-risk surgical population. N Engl J Med. 2011;365:591–600
16. Myles PS, Leslie K, McNeil J, Forbes A, Chan MT. Bispectral index monitoring to prevent awareness during anaesthesia: the B-Aware randomised controlled trial. Lancet. 2004;363:1757–63
17. Ghoneim MM, Block RI, Haffarnan M, Mathews MJ. Awareness during anesthesia: risk factors, causes and sequelae: a review of reported cases in the literature. Anesth Analg. 2009;108:527–35
18. American Society of Anesthesiologists Task Force on Intraoperative Awareness. . Practice advisory for intraoperative awareness and brain function monitoring. Anesthesiology. 2006;104:847–64
19. Avidan MS, Palanca BJ, Glick D, Jacobsohn E, Villafranca A, O’Connor M, Mashour GABAG-RECALL Study Group. . Protocol for the BAG-RECALL clinical trial: a prospective, multi-center, randomized, controlled trial to determine whether a bispectral index-guided protocol is superior to an anesthesia gas-guided protocol in reducing intraoperative awareness with explicit recall in high risk surgical patients. BMC Anesthesiol. 2009;9:8
20. von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JPSTROBE Initiative. . The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet. 2007;370:1453–7
21. Jeske HC, Lederer W, Lorenz I, Kolbitsch C, Margreiter J, Kinzl J, Benzer A. The impact of business cards on physician recognition after general anesthesia. Anesth Analg. 2001;93:1262–4
22. Zvara DA, Nelson JM, Brooker RF, Mathes DD, Petrozza PH, Anderson MT, Whelan DM, Olympio MA, Royster RL. The importance of the postoperative anesthetic visit: do repeated visits improve patient satisfaction or physician recognition? Anesth Analg. 1996;83:793–7
23. Brown DL, Warner ME, Schroeder DR, Offord KP. Effect of intraoperative anesthetic events on postoperative patient satisfaction. Mayo Clin Proc. 1997;72:20–5
24. Kynes JM, Schildcrout JS, Hickson GB, Pichert JW, Han X, Ehrenfeld JM, Westlake MW, Catron T, Jacques PS. An analysis of risk factors for patient complaints about ambulatory anesthesiology care. Anesth Analg. 2013;116:1325–32
25. Aust H, Eberhart LH, Kalmus G, Zoremba M, Rüsch D. [Relevance of five core aspects of the pre-anesthesia visit: results of a patient survey] [in German]. Anaesthesist. 2011;60:414–20
26. Soltner C, Giquello JA, Monrigal-Martin C, Beydon L. Continuous care and empathic anaesthesiologist attitude in the preoperative period: impact on patient anxiety and satisfaction. Br J Anaesth. 2011;106:680–6
27. Edward GM, de Haes JC, Oort FJ, Lemaire LC, Hollmann MW, Preckel B. Setting priorities for improving the preoperative assessment clinic: the patients’ and the professionals’ perspective. Br J Anaesth. 2008;100:322–6
28. Wachtel RE, Dexter F. A simple method for deciding when patients should be ready on the day of surgery without procedure-specific data. Anesth Analg. 2007;105:127–40
29. Wachtel RE, Dexter F. Influence of the operating room schedule on tardiness from scheduled start times. Anesth Analg. 2009;108:1889–901
30. Smallman B, Dexter F. Optimizing the arrival, waiting, and NPO times of children on the day of pediatric endoscopy procedures. Anesth Analg. 2010;110:879–87
31. Madan AK, Tichansky DS. Patients postoperatively forget aspects of preoperative patient education. Obes Surg. 2005;15:1066–9
32. Gillies A, Gillies R, Weinberg L. Patient recollections of perioperative anaesthesia risks. Anaesth Intensive Care. 2013;41:247–50
33. Scheer AS, O’Connor AM, Chan BP, Moloo H, Poulin EC, Mamazza J, Auer RC, Boushey RP. The myth of informed consent in rectal cancer surgery: what do patients retain? Dis Colon Rectum. 2012;55:970–5
34. Priluck IA, Robertson DM, Buettner H. What patients recall of the preoperative discussion after retinal detachment surgery. Am J Ophthalmol. 1979;87:620–3
35. Hutson MM, Blaha JD. Patients’ recall of preoperative instruction for informed consent for an operation. J Bone Joint Surg Am. 1991;73:160–2
36. Crepeau AE, McKinney BI, Fox-Ryvicker M, Castelli J, Penna J, Wang ED. Prospective evaluation of patient comprehension of informed consent. J Bone Joint Surg Am. 2011;93:e114(1–7)
37. Hekkenberg RJ, Irish JC, Rotstein LE, Brown DH, Gullane PJ. Informed consent in head and neck surgery: how much do patients actually remember? J Otolaryngol. 1997;26:155–9
38. Sahin N, Oztürk A, Ozkan Y, Demirhan Erdemir A. What do patients recall from informed consent given before orthopedic surgery? Acta Orthop Traumatol Turc. 2010;44:469–75
39. Praplan-Pahud J, Forster A, Gamulin Z, Tassonyi E, Sauvanet JP. Preoperative sedation before regional anaesthesia: comparison between zolpidem, midazolam and placebo. Br J Anaesth. 1990;64:670–4
40. Cheng BC, Chen PP, Cheng DC, Chu CP, So HY. Recall of preoperative anaesthesia information in Hong Kong Chinese patients. Hong Kong Med J. 2002;8:181–4
41. Ferrús-Torres E, Valmaseda-Castellón E, Berini-Aytés L, Gay-Escoda C. Informed consent in oral surgery: the value of written information. J Oral Maxillofac Surg. 2011;69:54–8
42. Park DC, Smith AD, Lautenschlager G, Earles JL, Frieske D, Zwahr M, Gaines CL. Mediators of long-term memory performance across the life span. Psychol Aging. 1996;11:621–37
43. Buckner RL. Memory and executive function in aging and AD: multiple factors that cause decline and reserve factors that compensate. Neuron. 2004;44:195–208
44. Strange BA, Hurlemann R, Dolan RJ. An emotion-induced retrograde amnesia in humans is amygdala- and beta-adrenergic-dependent. Proc Natl Acad Sci U S A. 2003;100:13626–31
45. Hurlemann R, Hawellek B, Matusch A, Kolsch H, Wollersen H, Madea B, Vogeley K, Maier W, Dolan RJ. Noradrenergic modulation of emotion-induced forgetting and remembering. J Neurosci. 2005;25:6343–9