Finally, the correlation (r) between a subject's preinterview anxiety (T1) and the change in anxiety observed at separation to the operating room (T4-T1) was -0.5 (P < 0.001) for the control group and -0.46 (P < 0.001) for the intervention group. That is, the more anxious the parents were before the preoperative interview, the less they experienced an increase in their anxiety upon separation from their children to the operating room.
This study demonstrates that the vast majority of parents prefer to have comprehensive information concerning their child's general anesthetic, including information about all possible complications. Moreover, in parents of children undergoing general anesthesia and outpatient surgery, very detailed anesthetic information of what might go wrong does not increase parental anxiety, and has the advantage of allowing parents a fully informed choice.
Comparative studies investigating anxiety levels in patients given a limited amount of information versus more detailed information concerning procedural and anesthetic risks report conflicting results. Alfidi  found that, although the majority of patients were satisfied when they received more detailed information about the risks of angiography, up to 35% of patients were made uncomfortable by the information. Similarly, in a study by Miller and Mangan , adult patients who were given extensive information preoperatively were found to be more tense, depressed, and uncomfortable. Conversely, no increase in preoperative anxiety was demonstrated in a study of British and Scottish men undergoing elective herniorrhaphy when presented with detailed risk information  or in Danish patients undergoing general anesthesia . Likewise, in a recent study performed in Australia, Inglis and Farnill  showed that patients who received detailed information, including numerical estimates of anesthesia-related complications, were no more anxious than those given minimal information regarding risks.
Some of these contradictory results may be explained by the methodological complexity of this issue. None of the previous studies have examined the effect of variables, such as coping, on the response of the individual patient, and most studies used global measures of anxiety with no documentation of adequate instrument reliability and validity. In addition, previous studies (excluding one) were performed with subjects from Great Britain, Denmark, and Australia, leaving open the question of American subjects' reactions to extended anesthetic information on preoperative anxiety. The only published American study to date is by Lankton et al.  who used a linear visual analog anxiety scale and a single numerical estimate to compare two groups of patients who either received no information or information about eight significant risks . The anxiety level after the provision of information in that study, however, was determined in the operating room, after the patients were premedicated with secobarbital. Furthermore, all previous investigations were conducted either the day before surgery or on the day of surgery, and it is possible that, as time passes between receiving detailed risk information and surgery, rumination in patients will result in increased anxiety . In addition, most patients now receive their preoperative anesthesia evaluation either on the morning of or several days in advance of surgery and thus conclusions obtained from previous investigations may be irrelevant for the present clinical practice.
We have noted that in the analysis of Phase 1, parents who were studied on the day of surgery indicated that they have a right to know about both all possible complications and common complications less frequently than parents who completed the questionnaire one to three days prior to surgery. This phenomenon may be related to a greater degree of situational anxiety experienced by parents on the day of surgery. We also demonstrated that increased desire for information was not related to variables such as age, race, marital status, educational level, history of previous hospitalizations, ASA status, and the surgical procedure the child underwent. All parents studied had a consistently high desire for information. We should emphasize, however, that our study population for Phase 1 consisted of parents of children ASA physical status I or II who were about to undergo outpatient surgery, and it is unclear from these data how parents of sick children, ASA III or IV, undergoing major nonelective surgery would respond.
For anesthesiologists, the issue of informed consent poses a special dilemma. Although we recognize the legal and moral need for informed consent, we must consider the effects of extensive information disclosure on patients, specifically with respect to increased anxiety. Increased preoperative anxiety in adults has been shown to correlate with postoperative outcomes, such as increased postoperative analgesic requirements and prolonged recovery and hospital stay . Further, increased parental preoperative anxiety has been shown to result in increased preoperative anxiety in their children, which in turn may lead to immediate postoperative negative psychological changes, such as sleep and eating disturbances and new onset enuresis . We should, however, recognize that anxiety is only one of the issues that needs to be considered when discussing informed consent. Indeed, the primary rationale of informed consent is to support and respect the autonomy of the patient, and not to decrease anxiety. That is, some patients may want to know all possible risks of anesthesia and surgery, even though it makes them exceedingly anxious.
Currently there is a considerable debate in the anesthesia literature, and in medical literature generally, regarding how far the anesthetic disclosure should extend. Gild  in his review article recommended that "it would not be unreasonable to mention all material risks, i.e., those risks which the average, reasonable patient would regard as significant." More recently, Litman et al.  recommended that an informed consent should include mention of any risk that "would result in permanent severe injury." In contrast, Waisel and Truog  recommended that the information provided should be tailored to fit the special needs of each individual. The findings of our study do not support the use of therapeutic privilege in withholding information about the risks associated with general anesthesia. We therefore believe that informed consent should strike a balance between providing the patient with details regarding significant risks while considering the individual needs of each patient.
It is important to note several methodological issues concerning this investigation. First, there is no gold standard to measure preoperative anxiety. However, we have used the STAI, developed by Spielberger, which is the most widely used anxiety instrument in the medical literature. In fact, the STAI was referred to recently in a major anesthesia journal as the gold standard for measuring preoperative anxiety . Second, this investigation was based on the assumption that information given to the patients was understood. The script used for the present investigation (Appendix II) was adapted from a previous Australian study by Inglis and Farnill . According to the Flesch Readability formula, the control script was in the fairly easy category, equivalent to six years of education, and the intervention script was in the standard range, equivalent to seven to eight years of education . In our study population, however, 85% of the control group and 94% of the intervention group parents had more than 12 years of education (Table 3). Further, even after we excluded all parents with less than 12 years of formal education, our findings persisted. Finally, all children involved in Phase 2 of this investigation were of ASA physical status I or II who underwent elective outpatient surgery and it is unclear from this investigation how parents with a history of previous surgery or hospital experience, or parents of sick children, ASA III or IV, undergoing major nonelective surgery would respond to different levels of anesthetic risk information. However, nonelective or major surgery shares most of the anesthetic risks associated with elective outpatient surgery.
In conclusion, this study demonstrates that most parents prefer to have comprehensive information concerning their child's perioperative period. Further, very detailed anesthetic information of what might go wrong does not increase parental anxiety and has the advantage of allowing parents a fully informed choice.
EASI (Emotionality, Activity, Sociability, Impulsivity) Instrument of Child Temperament
() Temperament refers to individual patterns of behaviors and responses to daily events and is closely akin to personality in adults. This instrument includes 20 items in four behavioral categories: emotionality, activity, sociability, and impulsivity. The ratings are made by the parent on a five-point scale, and a score ranges from 5 to 25 for each category with higher scores indicating higher baseline emotionality, activity, sociability, or impulsivity. The instrument has good validity (r = 0.77) when compared against other measures of temperament for preschool children. Testretest reliability of the EASI was 0.83 when mothers were rating their preschool children on adjacent months.
State-Trait Anxiety Inventory (STAI)1
This is a widely used self-report instrument that estimates situational and baseline anxiety in adults on the basis of responses to 40 statements1. Parents were asked to respond on a four-point scale; total scores for situational and baseline questions separately range from 20 to 80 with higher scores denoting higher levels of anxiety. Test-retest correlations for the STAI are reported to be high, ranging from 0.73 to 0.86.1 Validity was examined in two studies in which the STAI was given under high- and low-stress conditions to large samples of students. The r value ranged from 0.83 to 0.94, suggesting very good validity.1
Stressful Situation Coping Instrument (SSCI)
() Adult subjects and parents of children undergoing surgery indicate a recent stressful life event and then answer 19 yes/no items probing how they dealt with the event. This instrument was developed by Billing and Moos  and consists of three major coping categories: active-cognitive, active-behavioral, and avoidance.
Visual Analog Scale (VAS)
([11,12]) This scale is widely used as both a self-report and observational measure of anxiety. The VAS rating system consists of a 100-mm line that pictorially represents two behavioral extremes at either end of the continuum, i.e., "not anxious" (score of 0) and "extremely anxious" (score of 100). For the purpose of this study, the VAS was used as an observational measure to rate the children and as a self-report measure for the parents. Test-retest reliability of the VAS ranges from 0.61 to 0.73 when measured on adjacent days [12,23]. Also, when used to measure anxiety, the VAS has good validity against a self-rating depression scale (r = 0.64-0.67) .
The highly detailed information group received the full script, including the italicized sections. The routine information group did not receive the italicized sections.
I would like to discuss what will be done by the anesthesiologist during your child's operation and give you information about anesthesia and its risks.
During the entire procedure, the anesthesiologist will measure heart rate, blood pressure, oxygen level, and temperature. This allows us to give the proper amount of anesthesia so that your child does not feel or remember the operation. An intravenous line will be inserted to give fluids and medicines. A breathing tube will be placed into the windpipe/trachea to allow oxygen and anesthesia to be delivered. After the operation, your child will be taken from the operating room to the recovery area so that we can continue to monitor her/him. We will give any medicine necessary to keep your child comfortable.
Although the monitors and medicine we use today make anesthesia very safe, it is not without risks. Some risks are associated with minor discomfort or injury; these events occur commonly but do not cause permanent damage. For instance, nausea and vomiting occurs in 1 in 4 patients; sore throat or hoarseness occurs in 1 in 3 patients, and abrasions or bruising of lips and intravenous sites occurs in 1 in 10 patients. In addition, anesthesia can make your child feel disoriented or sluggish afterward.
Other complications are more serious but occur much less frequently. Because your child is healthy, I do not expect any serious complication to occur. However, breathing difficulty from aspiration of stomach contents occurs in 1 in 10,000 patients; damage to teeth or dental work occurs in 1 in 30,000 patients; and remembering events while under anesthesia occurs in 1 in 200,000 patients.
The most devastating complications of anesthesia are the most rare. Brain damage occurs in 1 in 80,000 patients; death occurs in 1 in 200,000 patients. These complications generally occur when a patient has a severe reaction to a drug or when blood flow or oxygen delivery is insufficient. Again, these events happen rarely and every precaution will be taken to ensure that your child will remain healthy.
The authors would like to thank Paul G. Barash, MD, for his critical review of this manuscript.
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© 1997 International Anesthesia Research Society
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