Preoperative Anxiolysis: It’s Not Just “Two of Midaz”
Michael P. Hutchens MD, MA
William Thomas Green Morton did not meet his patient before their encounter in the Ether Dome on October 16, 1846, as he was running late. Robert Hinckley’s painting of the scene depicts an anxiety-producing environment—the patient strapped to a chair, the focus of attention in an auditorium full of surgeons. Gilbert Abbott might have benefited from 2 mg of midazolam, had it been available; but perhaps he would then have been unable to tell the audience, as he did immediately postoperatively, that the operation had been painless. As far as history records, his perioperative experience was satisfactory to him, entirely without premedication or a preanesthetic interview. Nonetheless, the preoperative anxiety of Gilbert Abbott and that of modern patients has implications for patient satisfaction and for patient care and physiology. Preoperative anxiety is common—conservatively 25% and up to 80% in some studies. Concerns associated with anxiety include postoperative pain, incapacitation, and death. Preoperative anxiety is correlated with delayed gastric emptying, with increased intraoperative heart rate and anesthetic requirements, and with increased postoperative pain scores.
It remains unclear what preoperative strategy is most effective, in most patients, in reducing perioperative anxiety. Based on a 1997 survey, most U.S. anesthesiologists give anxiolytic medication as part of this therapy, but there are significant geographic, patient age, and hospital size variations. There is no consensus in the literature, and the number of regimens investigated is large and diverse. What is most clear is that patients have increased anxiety before operations, and that interventions performed by anesthesiologists can reduce that anxiety.
An oft-cited study purporting to show that the anesthetic interview is more effective than pentobarbital premedication was performed in 1963, but this study was methodologically flawed. The most anxious patients (those who kept the interviewer past the allotted time) were dropped from the study, but only in the interview arm. There was no assessment of baseline (prehospital) anxiety and no objective measure of anxiety. All patients received intramuscular atropine before assessment, patients were not aware they were part of a study despite being administered study medications, and it is unlikely that it is possible to blind an observer to whether a patient has
received pentobarbital, as investigators claimed to have done. The literature on premedication and preoperative anxiolysis is rife with similar methodologic problems (although, thankfully, not the absence of consent). However, at least one well-designed study shows that a visit from an anesthesiologist can play a significant role. In a 1977 study conducted in Britain, Leigh et al. used an objective psychometric questionnaire to assess baseline preoperative anxiety and that after no intervention, a preoperative visit, or viewing a 10-page booklet on anesthesia. All patients had more than normal anxiety preoperatively. The preoperative visit was significantly more effective in reducing anxiety than the booklet or no intervention.
received pentobarbital, as investigators claimed to have done. The literature on premedication and preoperative anxiolysis is rife with similar methodologic problems (although, thankfully, not the absence of consent). However, at least one well-designed study shows that a visit from an anesthesiologist can play a significant role. In a 1977 study conducted in Britain, Leigh et al. used an objective psychometric questionnaire to assess baseline preoperative anxiety and that after no intervention, a preoperative visit, or viewing a 10-page booklet on anesthesia. All patients had more than normal anxiety preoperatively. The preoperative visit was significantly more effective in reducing anxiety than the booklet or no intervention.
Although the content and tone of the preoperative visit have not been objectively evaluated, several basic principles of physician-patient interaction apply. There is no other physician-patient interaction in which the conscious, competent patient has greater reason for anxiety and is meeting a physician for the very first time. Patient concerns and anxiety must be taken seriously. Although some of these concerns may seem trivial or unusual, they are foremost in the patient’s mind and need to be addressed with compassion. An example is fear of intraoperative awareness. Anesthesiologists know that intraoperative awareness is an extremely rare event, that it is almost never complete awareness, and that it is associated with certain situations and kinds of anesthetics. Laypersons do not have access to this knowledge, and the only information to which they may have access (perhaps a television program or a magazine article) will have presented a population in which 100% of subjects are affected (“victims” or “survivors”) with the most extreme awareness and are hurt or disabled as a result. It may be a challenge to encourage patients to believe an unknown, new authority rather than one they trust and with whom they are familiar. No pharmacologic agent can substitute for this process; one must simply pay serious attention to patients, gain their trust, and state clearly that it is the anesthesiologist’s central concern to assure their safety and comfort. Indeed, amnesia produced by preoperative medication may erode some of the benefit of such a conversation if it is not remembered postoperatively.