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Parental Desire for Perioperative Information and Informed Consent: A Two-Phase Study

Kain, Zeev N. MD; Wang, Shu Ming MD; Caramico, Lisa A. MD; Hofstadter, Maura PhD; Mayes, Linda C. MD

Pediatric Anesthesia
Free

The purpose of this investigation was to identify the perioperative anesthetic information parents want from the anesthesiologist, and to determine whether the provision of detailed anesthetic risk information is associated with increased parental anxiety.The investigation consisted of a cross-sectional study followed by a randomized controlled trial. In Phase 1, baseline and situational anxiety, coping strategy, and temperament were obtained from parents of children undergoing surgery (n = 334). A questionnaire examining the desire for perioperative information was administered to all parents. In Phase 2, 47 parents were randomly assigned to receive either routine anesthetic risk information (control) or detailed anesthetic risk information (intervention). The effect of the intervention on parental anxiety was assessed over four time points: prior to the intervention, immediately after the intervention, day of surgery in the holding area, and at separation to the operating room. For Phase 1, the majority of parents (>95%) preferred to have comprehensive information concerning their child's perioperative period, including information about all possible complications. For selected items, increased parental educational level was associated with increased desire for information (P < 0.05). For Phase 2, when the intervention group was compared with the control group, there were no significant differences in parental anxiety over the four time points [F(1,45) = 0.6, P = 0.4]. Also, the interaction between time and group assignment was not significant [F(3,135) = 1.66, P = 0.18]. We conclude that parents of children undergoing surgery desire comprehensive perioperative information. Moreover, when provided with highly detailed anesthetic risk information, the parental anxiety level did not increase.

(Anesth Analg 1997;84:299-306)

Departments of (Kain, Wang, Caramico, Hofstadter) Anesthesiology, (Mayes) Yale Child Study Center, and (Kain, Mayes) Pediatrics, Yale University School of Medicine, New Haven, Connecticut.

Accepted for publication October 21, 1996.

Address correspondence and reprint requests to Zeev N. Kain, MD, Department of Anesthesiology, Yale University School of Medicine, 333 Cedar St., New Haven, CT 06510-8051.

Studies in the United States and Europe have shown that many patients are dissatisfied with the amount of perioperative information received from their physicians [1-3]. A recent British survey of over 5000 randomly chosen adult patients revealed a considerable lack of knowledge relating to the perioperative period [1]. To rectify this situation, it is essential to identify the aspects of perioperative management about which patients desire the most information [2]. The desire for information among parents of children undergoing surgery is of particular interest, as parents frequently are more concerned with their child's health than with their own.

Anesthesiologists have an ethical and legal responsibility to provide patients with detailed anesthetic risk information when obtaining the informed consent before surgery. How far disclosure must extend remains controversial. A common reason given for not providing detailed anesthetic risk information is that it may result in increased anxiety. Although an early study suggested that detailed procedural information may lead to increased patient anxiety [4], more recent reports disagree [5-7]. All previous investigations regarding detailed anesthetic information were conducted either the day before surgery or on the day of surgery. Inglis and Farnill [5] suggested in their recent study that it is possible that increased anxiety in patients provided with detailed anesthetic risk information may eventually develop given enough time for contemplation of the risk information. Furthermore, with the increasing practice of same-day admission surgery, the traditional preoperative visit the evening before surgery has been virtually eliminated and most patients now receive their preoperative anesthesia evaluation either on the morning of surgery or several days before the day of surgery. Since the timing of the anesthesiologist's preoperative interview may have an effect on the anxiety level of the patient [5,8], previous investigations regarding detailed anesthetic risk information may be irrelevant for the present practice.

The purpose of Phase 1 of this investigation was to identify the information that parents want from the anesthesiologist about the perioperative period. In Phase 2, we hypothesized that the provision of detailed information about anesthesia-related risk, including incidence of adverse outcomes, is associated with increased parental anxiety.

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Methods

This investigation consisted of a cross-sectional study followed by a randomized controlled trial. The study population was drawn from consecutive parents of children who underwent surgery and general anesthesia at the Children's Hospital of Yale-New Haven. Non-English-speaking parents were excluded from the study. Only one parent per child was allowed to participate in the study. All subjects were recruited 0-10 days prior to surgery while the children were undergoing preoperative evaluation. After recruitment, sociodemographic data, including age, race, gender, marital status, educational level and income, birth order, number of siblings, family size, day care, and previous hospital and surgical experience were obtained. The study was approved by our institutional review board and informed consent was obtained from all parents.

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Assessment Tools

Data regarding the following behavioral assessment tools and questionnaires are reported in detail in Appendix I: Stressful Situation Coping Instrument (SSCI) [9]; Emotionality, Activity, Sociability, Impulsivity (EASI) Instrument of child temperament [10]; State-Trait Anxiety Inventory (STAI)1; and Anxiety Visual Analog Scale (VAS) [11,12].

(1) Spielberger CD. Manual for the State-Trait Anxiety Inventory (STAI: Form Y). Palo Alto, CA, Consulting Psychologists Press, 1983.

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Study Protocol-Phase 1

The study population for Phase 1 consisted of 361 parents of children between the ages of 4 and 12 yr, ASA physical status I or II, who underwent outpatient surgery and general anesthesia. Ten subjects declined participation in Phase 1 of the study and 17 patients did not complete the questionnaire (n = 334). This phase was conducted either during a preadmission visit (1-10 days prior to surgery) or on the day of surgery. Demographic data, baseline and situational anxiety (STAI), and coping strategy (SSCI) of the parent were obtained using validated behavioral instruments. Temperament (EASI) and situational anxiety (VAS) of the child were noted as well. Next, the Desire For Information Questionnaire, adapted from previous studies conducted in Australia, Scotland, and Canada, was administered to all parents [13,14]. Each questionnaire contained a list of 14 statements relating specific details of anesthesia and surgery. The parents indicated how they felt about receiving the information contained in each of the statements. The available choices were "Prefer not to know," "Would like to know," and "Have the right to know," and subjects were asked to indicate only one choice. An index of the overall desire for information (overall desire index) was calculated for each parent by applying the weights 1, 2, and 3 to the response categories "Prefer not to know," "Would like to know," and "Have the right to know," respectively.

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Study Protocol-Phase 2

Of the 334 parents who participated in Phase 1 of the study, 47 were enrolled in Phase 2. No parent declined participation in this phase of the study. These were parents of children aged 4-12 yr, ASA physical status I or II, who underwent elective outpatient surgery and general anesthesia. To avoid potential confounding variables, any history of previous surgery, hospitalization, chronic illness, or developmental delay disqualified parents and their children from participation in this phase of the study.

Immediately prior to the anesthetic interview, the anxiety of the parent (STAI) and child (VAS) was assessed (T1). Next, parents were randomly assigned to receive either routine anesthetic information (control) or detailed anesthetic information (intervention). The randomization was done using a random numbers table. The routine and detailed anesthetic information are included in Appendix II. Briefly, the highly detailed information included statistics about adverse outcomes associated with anesthesia (e.g., "Brain damage occurs in 1 in 80,000 patients; death occurs in 1 in 200,000 patients"), while the routine information included general statements (e.g., "other complications are more serious but occur much less frequently"). To standardize the manner in which the anesthetic information was presented, one of three attending anesthesiologists read the information as shown in Appendix II. All parents were given the opportunity to ask the investigator to clarify anything that they did not understand, after which their state anxiety was reassessed by a second STAI (T2). Timing of the intervention ranged from 1 to 10 days prior to surgery. On the day of surgery, parental anxiety was again assessed in the preoperative holding area (STAI, VAS) (T3) and after the child was taken into the operating room (STAI) (T4).

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Statistic and Analytic Approaches

For Phase 1 of the study, demographic variables were examined using inferential statistics, including unpaired Student's t-test and chi squared analysis. Items of the Desire For Information Questionnaire were analyzed by frequency distribution and chi squared statistics. To examine the effect of timing (in relation to surgery) of the preoperative interview on parental desire for information, we analyzed the results based on four time categories: the day of surgery, 1-3 days prior to surgery, 4-7 days prior to surgery, and more than 7 days prior to surgery. Analysis of variance was used to compare the "overall desire index" of the four time groups. Next, we examined the effect of timing on the desire for information for each of the 14 questionnaire items; this was done using a series of 3 x 4 tables. The association between the desire for information and various demographic variables was examined using Spearman correlation analysis, cross-tables, t-test, and analysis of variance. Also, stepwise multiple regression was used to determine which of the variables deemed relevant by the literature and our data could predict the desire for information. Comparisons were considered significant if P < 0.05.

For the second phase of the study, demographic variables were examined using inferential statistics, including t-tests and chi squared statistics. Sample size was calculated in advance and was based on STAI anxiety scores of patients after routine anesthetic interviews [5]. A 30% difference in the anxiety level (i.e., 35 +/- 12 vs 46 +/- 15) between the intervention and control groups was considered clinically significant. Thus, a sample size of 23 subjects in each group was sufficient to detect a 30% difference in anxiety level with a power of 0.8 and an alpha of 0.05. Statistical analysis over the four time points (i.e., T1-T4) was performed using repeated measures analysis of covariance with trait anxiety and coping strategy as covariates. Post hoc analysis was done using paired t-test with Bonferroni correction for multiple comparisons indicating significance at P < 0.013. The relation between a subject's preinterview anxiety (T1) and the change in anxiety observed at separation to the operating room (T4-T1) was examined by using scatter plots and by calculating the Pearson correlation coefficient [7]. Data are expressed as mean +/- SE.

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Results

Phase 1

Baseline and demographic variables are presented in Table 1. An overwhelming majority of parents indicated that they either "would like to know" or "have a right to know" for all the 14 items of the Desire for Information Questionnaire (Table 2). Of particular interest was the finding that most parents indicated that they would like to know or have a right to know about "all possible complications" (96%) and not only "common complications" (97%) or "dangerous complications" (95%). Scores on the overall desire index ranged from 15 to 42 with a median of 34.

Table 1

Table 1

Table 2

Table 2

Timing of the preoperative interview had no effect either on the overall desire index (P = 0.58) or on the responses to 12 of 14 questionnaire items (P > 0.05). Parents who were studied on the day of surgery, however, indicated that they have a right to know about all possible complications less frequently than parents who completed the questionnaire 1-3 days prior to surgery (49% vs 67%, P = 0.02). Similarly, parents who were studied on the day of surgery indicated that they have a right to know about common complications less frequently than parents who completed the questionnaire 1-3 days prior to surgery (44% vs 58%, P = 0.05).

We have also examined whether any of the demographic or baseline variables are a predictor for increased desire for information. Temperament of the child; race, gender, marital status, educational level, and income of parent; birth order, number of siblings, day care, previous hospital or surgical experience of the child and parent, ASA status, and the surgical procedure were not associated with an increased desire for information. Similarly, a multivariate linear regression model, in which the overall desire index was the outcome, identified no demographic predicators. For questionnaire items 2, 3, and 8-14, however, a large proportion of parents with a higher level of education chose the "have a right to know" option (P < 0.05).

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Phase 2

There were no significant differences between the control and intervention groups regarding demographics such as age, gender, educational level, or baseline anxiety and temperament of the child or parent (Table 3). The mean STAI preintervention anxiety scores of the routine and detailed information groups were 46 +/- 11 and 42 +/- 10, respectively (P = not significant). These means are similar to those reported by Spielberger1 for medical and surgical patients (42 +/- 14). There were no significant differences in parental anxiety for the two groups over the four time points [F(1,45) = 0.6, P = 0.4] (Figure 1). Also, the interaction between time and group assignment was not significant [F(3,135) = 1.66, P = 0.18] (Figure 1). Further, there was also no evidence to suggest that parents with an anxious personality (upper 25% of STAI trait subscale) who had been given highly detailed information became more distressed at any of the three postinterview assessments (P < 0.05) compared with calm parents (lower 25% of STAI trait subscale).

Table 3

Table 3

Figure 1

Figure 1

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.

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Discussion

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 [15] 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 [4], 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 [7] or in Danish patients undergoing general anesthesia [6]. Likewise, in a recent study performed in Australia, Inglis and Farnill [5] 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. [16] 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 [16]. 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 [5]. 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 [17]. 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 [18]. 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 [19] 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. [20] recommended that an informed consent should include mention of any risk that "would result in permanent severe injury." In contrast, Waisel and Truog [21] 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 [22]. 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 [5]. 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 [5]. 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.

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Appendix I

EASI (Emotionality, Activity, Sociability, Impulsivity) Instrument of Child Temperament

([10]) 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.

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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

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Stressful Situation Coping Instrument (SSCI)

([9]) 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 [9] and consists of three major coping categories: active-cognitive, active-behavioral, and avoidance.

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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) [12].

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Appendix II

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