Motoyama & Davis: Smith's Anesthesia for Infants and Children, 7th ed.

PART TWO – General Approach to Pediatric Anesthesia


Chapter 7 – Psychological Aspects of Pediatric Anesthesia

Zeev N. Kain

  

 

Psychological Preparation for Anesthesia and Surgery, 241

  

 

Incidence and Definition, 241

  

 

Identification of Children at Risk, 242

  

 

Psychological Preparation Programs,242

  

 

Parental Presence, 244

  

 

Behavioral Interventions, 248

  

 

Behavioral Outcomes of Preoperative Anxiety in Children, 249

  

 

Postoperative Behavioral Changes,249

  

 

Clinical Outcomes, 251

  

 

Summary, 252

Surgery and anesthesia induce considerable emotional stress on both parents and children. Because the consequences of this stress occur in the immediate postoperative period ( Aono et al., 1999 ; Holm-Knudsen et al., 1998 ; Kain and Mayes, 1996 ) and may remain long after the hospital experience has passed ( Chapman et al., 1956 ; Kain et al., 1999a , 1999b), it is one of the tasks of the pediatric anesthesiologist to ensure the psychologic as well as the physiologic well-being of patients. To minimize the emotional stress of anesthesia and surgery, the anesthesiologist must understand the psychological developmental milestones of childhood and anticipate situations that the child may find threatening. The latter can often be accomplished with a careful and thoughtful preoperative visit and by administering preoperative sedation when a comforting person alone is inadequate. During the preoperative visit to the patient, the anesthesiologist can optimally evaluate the levels of anxiety of both parent(s) and child, while assessing the child's medical condition. In this chapter, the psychological facets of hospitalization and surgery for children and the psychological and medical preparation of pediatric patients for anesthesia and surgery are discussed. A summary of premedications used for children undergoing anesthesia is included.

▪ PSYCHOLOGICAL PREPARATION FOR ANESTHESIA AND SURGERY

More than 4 million children undergo surgery in the United States each year, and it is estimated that 50% to 75% of these children experience significant fear and anxiety before their operation ( Corman et al., 1958 ; Vernon et al., 1965 ; Melamed and Siegel, 1975 ; Beeby and Hughes, 1980 ; Kain et al., 1996c ). Based on behavioral and physiological measures of anxiety, induction of anesthesia in children has been identified as the most stressful point during the entire preoperative period ( Kain and Mayes, 1996 ). Appropriate understanding and management of fear and anxiety before surgery are important because they can lead to both psychological and physiologic adverse outcomes. Increased child anxiety before surgery has been linked to outcomes such as parent satisfaction, perioperative neuroendocrine response, and postoperative, clinical, and psychological recovery ( Kain et al., 2002a ). As an indicator of the importance of preoperative anxiety, a panel of 72 anesthesiologists ranked various anesthesia low-morbidity clinical outcomes based on importance and frequency ( Macario et al., 1999 ). The three clinical outcomes with the highest combined score were incisional pain, nausea and vomiting, and preoperative anxiety. Thus, it is important to understand the psychological issues involved when a child undergoes surgery.

▪ INCIDENCE AND DEFINITION

Although the exact prevalence of preoperative anxiety in children is difficult to assess because of issues related to measurement and developmental variations, it is estimated that up to 75% of children are reported to exhibit significant psychological and/or physiologic manifestations of anxiety during the preoperative period ( Corman et al., 1958 ; Vernon et al., 1965 ; Melamed and Siegel, 1975 ; Beeby and Hughes, 1980 ; Kain et al., 1996c ). That is, every year up to 3 million children in the United States exhibit significant fear and anxiety before undergoing surgery.

Preoperative anxiety is operationally defined as a subjective feeling of tension, apprehension, nervousness, worry, and vigilance associated with increased autonomic nervous system activity ( Burton, 1984 ;Kain and Mayes, 1996 ). Children are threatened by anticipated parental separation, pain or discomfort, loss of control, uncertainty about “going to sleep,” and masked strangers working in a technical, sterile, non-child-focused environment. Younger children are more concerned about separation from parents, and older children are more anxious about the anesthetic and surgical processes. The stress and anxiety experienced by children during induction of anesthesia represent an interaction between child-related factors and environmental conditions in the operating room. Child-related factors include age and developmental maturity, previous experience with medical procedures and illness, individual capacity for affect regulation and trait anxiety, and parental trait anxiety ( Lumley et al., 1990 ; Lumley et al., 1993 ; Kain et al., 1996c ).

Operating room-related environment factors include factors such as interactions with the medical staff, intensity of lights, level of noise produced by the staff and instrument preparation, and number of medical personnel who interact with the child. Children may look scared and/or agitated, breathe deeply, tremble, stop talking or playing, and/or start to cry. Other children may become nauseous, wet themselves, have increased motor tone, and/or attempt to escape from the operating room personnel ( Burton, 1984 ; Kain and Mayes, 1996 ). These behaviors, which are likely to prolong the induction of anesthesia, give children a sense of control over the situation and therefore diminish the sense of helplessness.

▪ IDENTIFICATION OF CHILDREN AT RISK

The first step in psychologically preparing children to undergo surgery is the identification of those children who are at a particularly high risk to develop extreme anxiety and fear before surgery. This is particularly important in an environment that is sensitive to operational hospital and operating room costs. To date, studies looking into risk factors that affect the behavioral responses of children during the preoperative period have identified several categories: age, temperament and developmental stage of the child, trait (baseline) and state (situational) anxiety of the parent, various demographic characteristics of the child and parent, and quality of previous experience of the child with medical procedures.

Young children, between the ages of 1 and 5 years, are reported to be at the highest risk for developing significant anxiety before anesthesia and surgery ( Brophy and Erickson, 1990 ; Lumley et al., 1993 ;Vetter, 1993 ; Kain et al., 1996a, 1996c [66] [68]). At this age, children are particularly vulnerable because they are both young enough to be dependent on their parents and old enough to recognize the parent's absence. Additional factors enhancing the vulnerability of this age group include degree of inexperience in social contact, ability to communicate and benefit from psychological preparation, and ability to relieve anxiety through play ( Hyson, 1983 ). Although the younger child may not have the cognitive ability to anticipate potential dangers or painful situations during induction of anesthesia, the older child (older than 6 years) may anticipate pain and fear “going to sleep” ( Sparrow et al., 1984 ). Older children may also rely on a number of coping strategies, including verbal questioning and cognitive mastery (e.g., learning about heart monitors or about what surgeons do), to mediate their anxiety.

Children who have high trait anxiety and who have experienced in the past poor-quality medical encounters are at a particularly high risk to develop high anxiety during the preoperative period ( Kain et al., 1996a , 1996c). Interestingly, a child who presents for repeated surgical procedures may respond in either higher-than-expected preoperative anxiety levels or lower-than-expected preoperative anxiety levels. Based on a conditioned learning model, the preoperative situation presents unconditioned fear stimuli that occur repeatedly over short intervals. Thus, children's previous surgical and medical histories may either exacerbate or attenuate fear conditioning, and the quality of the previous medical experience (e.g., how distressing it was to the child) is more crucial than its occurrence ( Box 7-1 ).

BOX 7-1 

Risk Factors for Preoperative Anxiety

Child Related

Young age (1 to 5 years)

Poor previous experience with medical procedures and illness

Children with shy and inhibited temperament

Lack of developmental maturity and social adaptability

High cognitive levels

Not enrolled in daycare

Parent Related

High trait and state anxiety

Divorced parents

Parents who had multiple surgical procedures

Environment Related

Sensory overload

Conflicting messages

Operating

Several investigations indicate that children who have a shy and inhibited temperament present with higher levels of fear and anxiety on the day of surgery compared with other children ( Melamed and Ridley-Johnson, 1988 ; Kain et al., 1996c , 2001). Conversely, children who have a more socially adaptive temperament are less anxious in the perioperative settings ( Kain et al., 2001a ). Temperament in a child refers to individual patterns of behavior and has been compared with personality traits in adults ( Buss et al., 1973 ; Buss and Plomin, 1975 ). Kagan et al. (1987) reported that temperament characteristics can be used to predict how a child responds emotionally in a stressful situation; for example, children who are “shy” or “inhibited” tend to become more anxious in novel settings, as suggested by the adrenocortical response and elevated heart rate.

A child's anxiety before surgery is strongly affected by the state and trait anxiety of the parent ( Kain et al., 1996c , 2001a). Parental anxiety mediates the child's response to stressful situations through two pathways ( Kain and Mayes, 1996 ). First, while parents may act as stress reducers for their children, parents who are themselves more anxious in a given situation are less available to respond to their child's needs. Indeed, in these cases, the child's distress may further compound parental anxiety, thus rendering the parent increasingly less able to respond effectively. The second pathway of the effect of parental anxiety on a child's response reflects the genetics of parental disposition to being overanxious. It was described that mothers who were more anxious in the surgical setting had children who were also more anxious and that these mothers were less able to respond in these situations ( Kagan et al., 1987 ).

Divorced parents, parents with lower educational levels, and parents of children who were not enrolled in a daycare setting rate themselves as significantly more anxious preoperatively ( Kain et al., 1996a , 1996c). Finally, parents of children who are less than 1 year old, parents who themselves underwent multiple admissions, and parents of children who underwent multiple admissions all report being more anxious ( Litman et al., 1996 ; Shirley et al., 1998 ). Preoperative anxiety in young children undergoing surgery can be managed with behavioral or pharmacologic (preoperative sedative medication) interventions, or both ( Fig. 7-1 ).

 
 

FIGURE 7-1  Operational view of preoperative anxiety in children. ACT, anesthesia control time.

 

 

▪ PSYCHOLOGICAL PREPARATION PROGRAMS

The concept of psychological preparation of children and parents who undergo surgery was introduced almost 50 years ago ( Mellish, 1969 ; Robinson and Kobayashi, 1991 ). Earlier programs provided the child with information regarding the surgical and anesthetic procedures and sought to develop a rapport between the medical staff and the child ( Melamed and Siegel, 1975 ; Melamed et al., 1976 , 1978). In the 1970s, modeling preparation programs were introduced to multiple hospitals in the United States. These modeling programs included the use of illustrated books, video programs, and puppet shows (Melamed and Siegel, 1975 ; Melamed et al., 1976 , 1978). The theory behind these programs was that children would be prepared for the surgical experience by observing other children who underwent similar procedures. During the 1990s, the idea of family-centered care was introduced to medicine in general and to the area of preoperative preparation in particular ( Melamed, 1993 ). Coupled with the development of the child-life discipline and teaching of coping skills, these concepts dominate the preparation programs in current use. Child-life specialists are individuals who facilitate the child's coping and the perioperative adjustment of children and parents by providing play experiences using modeling techniques (AAP statement, 1993). Child-life specialists incorporate descriptions of the perioperative sensations children experience and provide opportunities to examine, rehearse, and “play” with perioperative equipment to be used in their care. Child-life specialists also aim to establish supportive relationships with children and parents and to teach relaxation skills and present information to the child and parent about the anesthetic and surgical procedures (AAP statement, 1993).

The frequency at which preparation programs aimed at children undergoing surgery are being used has changed over the past decades. Although these programs were scarce in the 1970s and 1980s, they became quite popular in the 1990s. In fact, in 1996 about 80% of all major acute care children's hospitals in the United States offered such programs to children and their parents ( O'Byrne et al., 1997 ). Unfortunately, the number of comprehensive preparation programs has been reported to decrease over the past few years; this new trend is likely the result of new economical constraints in the perioperative environment.

The type of preparation programs used varies significantly among the various children's hospitals in the United States ( O'Byrne et al., 1997 ). About 89% of children's hospitals are reported to provide narrative preparation, 87% provide operating room tours, 86% provide play therapy, and 84% provide printed material ( O'Byrne et al., 1997 ). More comprehensive preparation such as child-life preparation is provided at about 50% of children's hospitals, and relaxation is taught at about 40% of the hospitals ( O'Byrne et al., 1997 ). Interestingly, a panel of experts indicated their consensus regarding the effectiveness of psychological preparation programs before surgery ( O'Byrne et al., 1997 ). On a scale of 1 (least effective) to 9 (most effective), child life was ranked the most effective, followed by play therapy, operating room tour, and printed material ( O'Byrne et al., 1997 ).

Although the effectiveness of preparation programs in reduction of anxiety in the holding area is well established, their effectiveness for reducing anxiety during the induction process is questionable ( Kain et al., 1996a , 1998a). Methodologic flaws such as the absence of an appropriate outcome instrument and small sample size hinder many of the studies that report reduced child's anxiety. In fact, a study that included a validated outcome measure has clearly documented that while a comprehensive psychological preparation program (i.e., child life) is effective in reduction of anxiety in the holding area, it wasnot effective during the induction of anesthesia or in the recovery room period ( Kain et al., 1998a ). It is likely that the extreme anxiety experienced during induction of anesthesia inhibits processing and implementing of the content of the preoperative preparation program by children.

Considerations in Choosing a Preparation Program

It is vital to realize that psychological preparation programs have to be tailored based on the individual needs of each child. That is, a preparation program that is appropriate for a 3-year-old is not appropriate for a 12-year-old. Thus, once the type of the preparation has been chosen (e.g., child life versus a tour of the operating room), the preparation has to be individualized based on developmental considerations of the child.

Timing of the preparation in relation to the day of surgery is a significant factor. That is, children 6 years and older benefit most if they participate in the program more than 5 to 7 days before surgery and benefit the least if the program is given 1 day before surgery ( Melamed et al., 1976 ; Robinson and Kobayashi, 1991 ; Kain et al., 1996a ). This longer interval between the preparation and surgery is needed for the older children to have adequate time to process new information provided to them during the preparation process ( Melamed et al., 1983 ; Kain et al., 1996a , 1998a). Typically, older children prepared 1 week ahead of surgery show an immediate increase in the anxiety during the preparation period with a gradual decrease until the time of surgery ( Melamed et al., 1983 ). Interestingly, there may be a negative effect of a preparation program on younger children. This may be a result of the inability of children younger than 3 years to separate fantasy from reality ( Melamed et al., 1976 ; Robinson and Kobayashi, 1991 ). From ages 3 to 6 years, children experience increased ability to separate fantasy from reality, and by the age of 6, this distinction of fantasy versus reality is typically completed (Piaget, 1955 ).

Designing a preparation program for children who were previously hospitalized is a particular challenge. Information about what occurs on the day of surgery does not provide new information for these children. Studies have documented that simple modeling and play programs are not beneficial for these children and may actually sensitize these children ( Melamed et al., 1983 ; Faust and Melamed, 1984). Alternative psychological programs, such as extensive individualized coping skills training, combined with actual practice, is more helpful for these children ( Melamed et al., 1983 ; Kain et al., 1996a ). These alternative programs should be based on the particular experience the child had during the previous surgeries.

Parental Issues

Clearly, preoperative preparation should be directed to parents as well as to children. Multiple studies have reported that parents typically become very anxious when their child undergoes surgery ( Pinto and Hollandsworth, 1989 ; Kain et al., 1996a , 1996c; Litman et al., 1996 ; Shirley et al., 1998 ; Cassady et al., 1999 ), and parental anxiety was identified as a significant risk factor for increased preoperative anxiety in children ( Pinto and Hollandsworth, 1989 ; Kain et al., 1996a ; Litman et al., 1996 ; Cassady et al., 1999 ). Parents experience preoperative anxiety for reasons such as separation and bodily harm to their children, guilt, and financial stresses ( Cassady et al., 1999 ). Indeed, many parents are more anxious regarding their children's health than their own ( Kain et al., 1997d ). Mothers are more prone to preoperative anxiety than are fathers ( Litman et al., 1996 ; Shirley et al., 1998 ). Compared with fathers, mothers are known to be more anxious preoperatively when their child is less than 1 year old or when coping with their child's first surgical experience ( Litman et al., 1996 ). Previous research has also documented that women are significantly more concerned with risks and side effects in general, although men specifically articulate a fear of death twice as often as do women.

Parents who undergo a preoperative preparation program or who have viewed a preoperative videotape featuring factual information about anesthesia display reduced preoperative anxiety on the day of surgery ( Table 7-1 ) ( Pinto and Hollandsworth, 1989 ; Kain et al., 1996a ; Cassady et al., 1999 ) but not during the anesthetic induction, in the recovery room, and at 2 weeks postoperatively ( Kain et al., 1998a ). Presently, the use of videotapes is receiving increasing attention as a supplementary educational modality for parents ( Karl et al., 1990 ; Cassady et al., 1999 ) because they are informative, perhaps anxiolytic, and cost effective in certain settings ( Pinto and Hollandsworth, 1989 ; Cassady and Kain, 2000 ).


TABLE 7-1   -- Use of preoperative video for increased parental education and decreased parental anxiety

 

EXPERIMENTAL GROUP

CONTROL GROUP

P Value

Measure

Prevideo

Postvideo

Prevideo

Postvideo

 

SALT (% correct)

75.2 ± 1.8

84.9 ± 2.3

73.4 ± 1.4

75.4 ± 1.9

<.0220

STAI State Anxiety

40.5 ± 1.7

36.0 ± 1.4

39.2 ± 1.5

37.7 ± 1.2

<.0310

APAIS Total

22.0 ± 1.2

17.0 ± 0.9

22.0 ± 0.8

21.6 ± 0.7

<.0001

APAIS Anxiety

12.7 ± 0.8

9.0 ± 0.6

12.6 ± 0.6

12.2 ± 0.5

<.0001

APAIS Need for Information

9.3 ± 0.7

8.0 ± 0.3

9.4 ± 0.6

9.3 ± 0.6

<.0001

From Cassady JF Jr, Wysocki TT, Miller KM, and others: Use of a preanesthetic video for facilitation of parental education and anxiolysis before pediatric ambulatory surgery. Anesth Analg 88:246–250, 1999.

Values are given as mean ± SEM.

SALT, Standard Anesthesia Learning Test; STAI State Anxiety, State-Trait Anxiety Inventory (State Anxiety); APAIS, Amsterdam Preoperative Anxiety and Information Scale.

Group × time interaction obtained by repeated-measures analyses of variance.

 

 

 

 

Future of Preparation Programs

The need for preoperative preparation programs that are cost sensitive created a void that will inevitably be filled technologically. The future will be characterized by the development and implementation of computerized multimedia displays and interactive technology. The latter offers particular appeal, because its multimodal capability can provide specific interventions for individuals with a wide range of medical problems and coping styles. The capacity, programmability, and rapid response of current interactive technology are suitable for such tasks, but the cost remains high. In the future, it is the hope that all children and their parents will be able to realize the benefits of specialized, technologically advanced educational systems programmed to meet their individual and cultural needs and coping styles.

▪ PARENTAL PRESENCE

Parental presence during the induction of anesthesia has been suggested as an alternative to sedative premedication. Although there is general agreement about the desirability of parents visiting during their child's hospitalization, their presence during invasive medical procedures, such as induction of anesthesia, remains very controversial ( Lerman, 2000 ; Kain, 2001 ). Potential benefits from parental presence include reducing the need for preoperative sedatives and reducing the child's anxiety and distress on separation to the operating room. Increased child compliance and reduced child anxiety during induction of anesthesia have been suggested to be benefits as well. Common objections to this practice include delays in operating room schedules, crowded operating rooms, and a possible adverse reaction of the parent during the induction process.

A large-scale nationwide survey indicated that there is a large variability in hospital policy in the United States toward parental presence in operating rooms. Thirty-two percent of the hospitals allow parental presence, 11% encourage parental presence, 23% have no formal hospital policy, and 26% do not allow it ( Kain et al., 2004b ).

The same survey reported that only 10% of anesthesiologists have parents present during induction of anesthesia in more than 75% of cases and that 27% of anesthesiologists have parents present during induction in less than 25% of cases. About 50% of all anesthesiologists never have parents present during induction ( Kain et al., 2004b ). The reported prevalence of parental presence varies widely among the different geographic locations in the United States.

Parental presence during induction of anesthesia was practiced most often in the northeast region and least often in the south central region of the United States ( Fig. 7-2 ). Interestingly, the findings in this survey ( Kain et al., 2004b ) are very much different from the findings in a nationwide survey conducted in 1995 ( Kain et al., 1997c ). Overall, there is an increase in the frequency of parental presence from 1995 to 2002, and the number of anesthesiologists who never allow parental presence dropped in every geographic region ( Kain et al., 1997c , 2004b). These findings may represent a new trend in this practice in the United States ( Fig. 7-3 ).

 
 

FIGURE 7-2  Practice of parental presence during induction of anesthesia as a function of geographic areas in the United States. PPIA, parental presence during induction of anesthesia.  (Kain ZN, Caldwell-Andrews AA, Krivutza DM, Weinberg ME, Wang SM, Gaal D: Trends in the practice of parental presence during induction of anesthesia and the use of preoperative sedative premedication in the United States, 1995-2002: results of a follow-up national survey. Anesth Analg 98:1252-9, 2004.)

 

 

 

 
 

FIGURE 7-3  Practice of parental presence during induction of anesthesia as a function of geographic areas in the United States. PPIA, parental presence during induction of anesthesia.  (Kain ZN, Caldwell-Andrews AA, Krivutza DM, Weinberg ME, Wang SM, Gaal D: Trends in the practice of parental presence during induction of anesthesia and the use of preoperative sedative premedication in the United States, 1995-2002: results of a follow-up national survey. Anesth Analg 98:1252-9, 2004.)

 

 

 

Parental Perspectives

A number of surveys have indicated that most parents prefer to be present during the induction of anesthesia regardless of the child's age ( Braude et al., 1990 ; Ryder and Spargo, 1991 ). Further, a majority of parents believe that they are of some help to their child and to the anesthesiologist during the induction process ( Ryder and Spargo, 1991 ). A study indicates that over 80% of parents chose to be present in the operating room when returning for a second operation regardless of whether they were present in the operating room in the first operation ( Kain et al., 2003b ). This preference for parental presence during induction shown by parents who had experience with other interventions, including preoperative midazolam, is similar to the preference for parental presence shown by parents of children undergoing surgery for the first time ( Kain et al., 2003b ) ( Fig. 7-4 ). It is no surprise, therefore, that parental presence during the induction of anesthesia is associated with increased parental satisfaction regarding not only the separation process from their child but also with the overall functioning of the hospital ( Kain et al., 2000 ).

 
 

FIGURE 7-4  Data regarding the parental intervention choice in the subsequent surgery as a function of the initial surgery. For example, 28% of the parents who were assigned to the premedication group in the initial intervention chose to be in the premedication group in the subsequent surgery. PPIA, parental presence during induction of anesthesia.  (Kain ZN, Caldwell-Andrews AA, Wang SM, Krivutza DM, Weinberg ME, Mayes LC: Parental intervention choices for children undergoing repeated surgeries. Anesth Analg 96:970-5, 2003.)

 

 

 

Many parents report increased anxiety when present during induction of anesthesia ( Vessey et al., 1994 ). An investigation found, however, that anxiety following induction of anesthesia among parents who were present during induction did not differ significantly from anxiety among parents who were not present during the induction process ( Kain et al., 2003a ). This finding is in agreement with previous randomized controlled trials that have examined this issue ( Bevan et al., 1990 ; Kain et al., 1996b , 1998b, 2000).

Parental physiologic responses during induction of anesthesia have been examined as well ( Kain et al., 2003a ). It was found that parental heart rate and skin conductance levels significantly increase as the parents walk to the operating room. Interestingly, once the induction begins, parental heart rate decreases, only to peak again once the parents have to leave the operating room. This second peak in heart rate is in agreement with previous data that indicate the most upsetting factors are seeing the child go limp during induction and then having to leave the child ( Vessey et al., 1994 ). Parental blood pressure following induction of anesthesia was not elevated and examination of parental Holter data revealed no rhythm abnormalities and no electrocardiographic changes indicating ischemia ( Kain et al., 2003a ) (Fig. 7-5 ).

 
 

FIGURE 7-5  Changes in parental heart rate (HR) from baseline measurement until after induction of anesthesia. Data are reported as mean (SE). *Time points at which differences between groups are statistically significant (P < .05). OR, operating room; PPIA, parental presence during induction of anesthesia.  (Kain ZN, Caldwell-Andrews AA, Mayes LC, Wang SM, Krivutza DM, LoDolce ME: Parental presence during induction of anesthesia: physiological effects on parents. Anesthesiology 98:58-64, 2003.)

 

 

 

There have been isolated reports of parental presence resulting in disruptive behavior, and even removal of a child from the operating room by a grandmother ( Schofield and White, 1989 ; Bowie, 1993 ). In contrast, a 4-year experience with 3,086 children in a free-standing ambulatory surgery center found that no parent needed to be escorted from the operating room ( Gauderer et al., 1989 ).

Experimental Studies Involving Parental Presence

Early studies involving parental presence during induction of anesthesia indicated that the presence of a parent might lower the anxiety of the child ( Schulman et al., 1967 ; Hannallah and Rosales, 1983 ). These studies, however, were nonrandomized, did not control for confounding variables, and lacked appropriate outcome measurement tools. It is important to note that measurement of a child's anxiety during induction of anesthesia is a complex issue that necessitates the use of a validated and reliable instrument of a child's anxiety. Such an instrument, the Yale Preoperative Anxiety Scale, was developed and validated a number of years ago (Kain et al., 1995, 1997b [54] [55]). Later studies that used appropriate sample size, eliminated confounding variables, and used appropriate end points and assessment instruments concluded that parental presence does not result in decreased child's anxiety during the induction process ( Hickmott et al., 1989 ; Bevan et al., 1990 ; Kain et al., 1996b , 1998b, 2000; Kain, 2001 ). Further, parental presence during induction of anesthesia was also compared with the use of oral midazolam (0.5 mg/kg) administered 30 minutes before surgery ( Kain et al., 1998b ). The investigations concluded that the use of oral midazolam is significantly more effective than parental presence in terms of both reduced child's anxiety and increased child's compliance ( Kain et al., 1998b ) (Fig. 7-6 ).

 
 

FIGURE 7-6  Anxiety of child across the perioperative period. Induction 1, entrance to the operating room; Induction 2, introduction of the anesthesia mask to the child. Premedication group was significantly less anxious compared with the parental presence and control groups at induction 1 (*) and induction 2 (**). PPIA, parental presence during induction of anesthesia; YPAS, Yale Preoperative Anxiety Scale.  (Kain ZN, Mayes LC, Wang SM, Caramico LA, Hofstadter MB: Parental presence during induction of anesthesia versus sedative premedication: which intervention is more effective? Anesthesiology 89:1147-1156, 1998.)

 

 

 

On critical examination of this area, however, one realizes that the basic concepts underlying parental presence during induction of anesthesia-related research have not changed during the past two decades and that the present body of research simply deals with the question of whether parents should be present during induction of anesthesia. Research interests should shift toward an emphasis on what parents actually do during induction of anesthesia rather than simply on their presence. A preliminary publication reports the development of an intervention that consists of an informational and modeling video, instructed graduated exposure and shaping exercises, coached distraction techniques, supportive telephone coaching, and adherence checks ( Kain et al., 2002b ). This informative modeling intervention is directed at parents of children undergoing surgery and is quite extensive. Results show that children and parents who underwent the extensive parental preparation program were significantly less anxious than were children whose parents were present during induction of anesthesia and who did not receive the preparation program. More data regarding this preparation program are needed.

Satisfaction Issues

Previously, the medical community held the view that the only “real” outcomes are those that have an immediate and direct impact on patient morbidity and mortality. This view has changed dramatically, and issues such as patient satisfaction and quality of life are considered by many as equally important as morbidity ( Ford et al., 1997 ). This new development is echoed in review articles in the anesthesia literature that suggest that patient satisfaction should serve as an important end point and indicator of overall quality of anesthesia care ( Fung and Cohen, 1998 ).

Typically, parents are not aware of any of the events that take place inside an operating room. To parents, the most important thing is their child's safety. However, with anesthetic mortality rates approaching 1:100,000, safety is expected. In contrast, parents evaluate an anesthesiologist, in part, based on the separation experience with their child. That is, if their child is taken to the operating room upset and crying, their satisfaction and impression of the anesthesiologist and the surgery center may be poor.

A study evaluated parental satisfaction as a function of their presence during induction of anesthesia. The study also evaluated the effectiveness of parental presence when used in conjunction with oral midazolam (0.5 mg/kg) ( Kain et al., 2000 ). The study has demonstrated that while parental presence did not provide added value in terms of reduced child's anxiety or increased child's compliance, it did improve parental satisfaction with both the separation process and the entire perioperative process ( Kain et al., 2000 ). Thus, although experimental studies fail to demonstrate the effectiveness of parental presence with regard to anxiety reduction or increased compliance, parental satisfaction seems to improve if the parents are present during the induction of anesthesia.

Medicolegal Issues

The practicing anesthesiologist should also be aware of legal issues associated with parental presence during induction of anesthesia-that is, what additional risks the anesthesiologist is incurring because of the presence of a parent in the operating room. The legal literature is not clear with this issue. Of note, however, is a decision made by the Illinois Supreme Court with regard to parental presence during an invasive procedure. In its verdict the Illinois Supreme Court stated that a hospital that allows a nonpatient to accompany a patient during treatment does not have a duty to protect the nonpatient from fainting ( Lewyn, 1993 ). If medical personnel invite the nonpatient to be present during the treatment, however, the hospital has a legal responsibility toward the nonpatient. Thus, there is an important distinction between allowing parental presence and inviting parental presence. As a response to such possible litigation, a number of hospitals require parents to sign a separate consent form when they express the wish to be present during induction of anesthesia. A nationwide survey indicated, however, that at the current time only 5% of all hospitals in the United States indicate that they routinely obtain a separate written consent for parental presence during induction of anesthesia ( Kain et al., 2004b ).

▪ BEHAVIORAL INTERVENTIONS

Music

Music has well-established psychological effects, including the induction and modification of moods and emotions ( Baeck, 2002 ; Kain et al., 2002a ; Lipe, 2002 ). Kane, in 1914, is reported to be one of the first individuals to provide intraoperative music to distract patients from “the horror of surgery” ( Kane, 1914 ). It was not until about 1960, however, that a group of dentists reported that between 65% and 90% of their patients needed little or no anesthesia for dental extractions with routine use of music during dental surgery ( Gardner and Licklider, 1959 ; Gardner et al., 1960 ). Music has gained popularity as a part of complementary medicine directed at patients undergoing medical and surgical procedures (Wang et al., 2002a, 2002b, 2003 [133] [135] [130]).

The role of music as a therapeutic modality for the treatment of preoperative anxiety in adult patients has been evaluated in several studies. Although a number of studies conducted in this area were hindered by multiple methodologic flaws, the anxiolytic effects of perioperative music are well documented in adults ( Standley, 1986 ; Miluck-Kolasa et al., 1996 ; Thompson and Kam, 1995 ; Wang et al., 2002a ). As indicated earlier, the anxiety experienced by a child during the induction period is related to personality factors as well as to operating room factors such as bright lights and high noise levels. Several studies that have assessed noise levels in the operating room concluded that while overall sound levels are not excessive, loud intermittent noises up to 108 dB are present intermittently ( Hodge and Thompson, 1990 ; Nott and West, 2003 ). Cohen classified noises as just audible (10 dB), very quiet (50 dB, comparable to light traffic at 30 miles/hr), moderately loud (70 dB, comparable to a dishwasher), very loud (90 dB, comparable to a food blender), and uncomfortably loud (130 dB, comparable to a rock-and-roll band) ( Cohen, 1970 ). Interestingly, a sudden noise with a level as little as 30 dB above the background noise (e.g., an Spo2 alarm) might cause an immediate startle response, which is associated with an activation of the sympathetic system and an anxiolytic response ( Falk and Woods, 1973 ). A study introduced an intervention that consisted of dimmed operating room lights (200 Lx) and soft background music (Bach's “Air on a G String” [50 to 60 dB]), and only the attending anesthesiologist was allowed to interact with the child during induction (Kain et al., 2001b) ( Fig. 7-7 ).

 
 

FIGURE 7-7  Levels of anxiety manifested by children during the perioperative period. Anxiety was assessed by the m-PAS (modified Yale Preoperative Anxiety Scale). Observed anxiety differed significantly between the two groups [F(1,67) = 6.3, P = .014]. LSSG, low sensory stimulation group; OR, operating room. *P = .03; **P = .003.  (Kain ZN, Wang SM, Mayes LC, Krivutza DM, Teague BA: Sensory stimuli and anxiety in children undergoing surgery: a randomized, controlled trial. Anesth Analg 92:897-903, 2001.)

 

 

 

The number of medical personnel interacting with the child is of particular importance as it is not infrequent that the surgeon, the circulating nurse, the anesthesia resident, and the anesthesia attending are all trying to help the child through the induction process. This may result in conflicting messages and increased anxiety of the child. The study found that this combination of music, dim light, and only the attending anesthesiologist interacting with the child was effective and those children who received this intervention exhibited significantly less anxiety during induction of anesthesia ( Kain et al., 2002b ).

To date, most reported studies of music therapy in the medical literature describe interventions that consist of patients passively listening to music. Interestingly, results from a meta-analytical review appear to indicate that studies using live-participation music therapy, although significantly fewer in number, showed overall higher effect sizes compared with engagement of the patient. Earlier studies that examined live-participation music therapy with children undergoing surgery concluded that this type of music therapy resulted in reduced anxiety in children undergoing surgery ( Chetta, 1981 ; Robb et al., 1995 ). These studies, however, were limited because of a small sample size and a lack of reliable and valid outcome anxiety measures. A more recent trial that used an appropriate sample size and a reliable outcome measure instrument indicated some complexities related to this issue ( Kain et al., 2004a ). The study found that at separation and on entrance to the operating room, only children who received music therapy from one of the therapists involved in the study were significantly less anxious than the control group. This anxiolytic effect was present only in the holding area and at separation but not during induction of anesthesia. Thus, one should conclude that the provision of live-participation music therapy is quite expensive, and considering the results of the more recent study, one can seriously doubt if this modality should be routinely used to reduce preoperative anxiety in all children undergoing surgery.

Acupuncture

Acupuncture originated in China between the years 2000 and 100 B.C.E. ( Hsu, 1996 ). Despite slow progression of scientific evidence, acupuncture and related techniques have become very popular in the western medical culture over the last few decades.

Several studies have examined whether acupuncture is an effective treatment modality for preoperative anxiety. Wang and Kain (2001a, 2001b) [131] [132] found that both healthy volunteers and adult patients undergoing routine outpatient surgery report lower levels of state anxiety after auricular acupuncture provided in specific points. This effect started as early as 30 minutes after insertion of the acupuncture needles. The use of acupuncture as a treatment for parental anxiety was examined as well. Wang and Kain randomized mothers of children who were scheduled for surgery to an acupuncture intervention group or a sham acupuncture control group ( Fig. 7-8 ). The intervention was performed at least 30 minutes before the child's induction of anesthesia and all mothers were present during induction of anesthesia.

 
 

FIGURE 7-8  Auricular acupuncture points that are used to treat parental anxiety.  (Wang SM, Maranets I, Weinberg ME, Caldwell-Andrews AA, Kain ZN: Parental auricular acupuncture as an adjunct for parental presence during induction of anesthesia. Anesthesiology100:1399-404, 2004.)

 

 

 

The investigators found that after induction, maternal anxiety in the acupuncture group was significantly lower and children whose mothers received the acupuncture intervention were significantly less anxious on entrance to the operating room ( Wang et al., 2004 ). Thus, auricular acupuncture may have various uses in the pediatric perioperative environment.

Preoperative Interview

There is no question that anesthesiologists have the ability to either increase or decrease the anxiety of patients; one should consider the preoperative interview as a psychological intervention that is administered routinely to parents and children ( Egbert et al., 1963 ; Kain et al., 2002a ). The anxiety-moderating effect of anesthesiologists is dependent on multiple variables such as environmental stimuli and the coping style of the parent. That is, while overall, patients undergoing surgery ask for all relevant information to be provided to them (Kain et al., 1997a, 1997d [49] [59]), some patients and parents have an information-seeking coping style, and others have an information-avoiding coping style ( Miller, 1995 ). The challenge for the anesthesiologist is to identify the individual coping style of a parent without the benefit of using structured psychological instruments during the preoperative visit.

The impact of information given in the preoperative settings on the anxiety of patients was examined. Miller and Mangan (1983) found that adult patients who were given extensive information preoperatively were more anxious and uncomfortable. In contrast, no increase in preoperative anxiety was demonstrated in a study that involved English and Scottish men undergoing elective herniorrhaphy who were presented with detailed risk information ( Kerrigan et al., 1993 ). Similarly, a study that involved parents of children undergoing surgery found that the provision of detailed anesthetic information in the setting of a randomized controlled trial did not increase the anxiety of the parents ( Kain et al., 1997d ). Thus, the practicing anesthesiologist should be aware of these data and provide information in the perioperative settings as dictated by the settings and the needs of the parents and the children.

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Motoyama & Davis: Smith's Anesthesia for Infants and Children, 7th ed.

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▪ BEHAVIORAL OUTCOMES OF PREOPERATIVE ANXIETY IN CHILDREN

▪ POSTOPERATIVE BEHAVIORAL CHANGES

Epidemiology

In 1945, Levy (1945) described 25 cases of children who developed significant fear of physicians after tonsillectomy. Vernon et al. (1966) developed a structured parental instrument (Posthospitalization Behavior Questionnaire [PHBQ]) that addressed the issue of postoperative behavioral changes in children. Earlier studies that used the PHBQ reported that up to 88% of all children undergoing anesthesia and surgery develop new-onset postoperative behavioral changes ( Vernon et al., 1966 ; Peterson and Shigetomi, 1982 ; Thompson and Vernon, 1993 ). More recent studies conducted in the United States and Europe documented that up to 54% of young children undergoing outpatient surgery experience general anxiety, nighttime crying, enuresis, separation anxiety, and temper tantrums at 2 weeks postoperatively ( Kain et al., 1996c ; Kotiniemi et al., 1996, 1997a [78] [77]; Kain, 2000 ) ( Fig. 7-9 ).

 
 

FIGURE 7-9  The incidence of postoperative behavioral changes as a function of time after surgery.  (Kain ZN, Mayes LC, O'Connor TZ, Cicchetti DV: Preoperative anxiety in children. Predictors and outcomes. Arch Pediatr Adolesc Med 150:1238-45, 1996.)

 

 

 

Nightmares and waking up crying are particularly common problems after surgery in children, and the incidence of these behaviors is as high as 20% at 2 weeks postoperatively ( Kain et al., 1996c ). The effect of outpatient surgery on postoperative sleep patterns was also addressed in a study that used actigraphy, which is an objective measure that aims to quantify sleep ( Kain et al., 2002d ). The study found that 47% of all children developed postoperative sleeping problems as assessed by either actigraphy or the PHBQ ( Kain et al., 2002d ). Fourteen percent of children experienced a decrease of at least 1 SD in percentage sleep as assessed by actigraphy ( Kain et al., 2002d ) ( Fig. 7-10 ).

 
 

FIGURE 7-10  Postoperative sleeping disturbances during the first 5 postoperative nights, as determined either by actigraphy or the Posthospitalization Behavior Questionnaire (PHBQ).  (Kain ZN, Mayes LC, Caldwell-Andrews AA, Alexander GM, Krivutza D, Teague BA, Wang SM: Sleeping characteristics of children undergoing outpatient elective surgery. Anesthesiology 97:1093-101, 2002.)

 

 

 

Considering the dramatic changes that have occurred with health care delivery, this relatively high incidence of postoperative behavioral changes is surprising ( Kain, 2000 ). That is, one would expect a lower incidence considering that these were studies that were conducted with outpatients. It is important to appreciate, however, that because of economical issues, outpatient surgery is being performed with children with high levels of medical acuity. These children underwent inpatient surgery just a few years ago; it may be that efforts to improve the psychological climate of hospitals may have been neutralized by other variables.

Predictors

Several studies report that young age is a significant risk factor for the development of postoperative behavioral changes. In 1945, Levy noted a marked reduction in the emotional reaction following surgery after the age of 3 years, when the incidence of the new-onset behaviors dropped from 50% to 10%. More recent investigations confirm this observation and report that these postoperative behavioral changes are most common in ages 1 to 4 years ( Vernon et al., 1965 ; Kain et al., 1996c ). At this age, children are particularly vulnerable because of issues such as separation anxiety, degree of inexperience in social contact, ability to communicate and benefit from psychological preparation, and ability to relieve anxiety through play ( Kain, 2000 ).

Increased anxieties of the child and of the parent in the holding area and during induction of anesthesia are both good predictors for later emergence of maladaptive postoperative behaviors ( Eckenhoff, 1958 ; Kain et al., 1996c, 1999a [68] [51]; Lumley et al., 1993 ). Meyers and Muravchick (1977) compared postoperative behavioral responses in a group of children who underwent a “steal induction” versus a group of children who underwent an “awake” induction. One month after discharge of the children from the hospital, the investigators reported that the rate of behavioral changes was 88% in the awake group and 58% in the steal group. Kain et al. (1999a) confirmed these previous findings and observed that extreme anxiety during induction of anesthesia and forcing the child to the table (‘brutane anesthesia’) is associated with a significantly increased occurrence of postoperative negative behavioral changes.

Several reports indicate that these behavioral changes are significantly more common among children undergoing tonsillectomy and genitourinary surgery ( Manley, 1982 ; Kain et al., 1996c ). Finally, positive behavioral changes have also been reported after surgery, particularly in children with chronic conditions (e.g., recurrent otitis media) that have been improved by the surgery ( Kain et al., 1996c ;Kotiniemi et al., 1996 ).

The issue of anesthetic techniques (intravenous versus mask) has not been demonstrated to be a significant predictor of the incidence of postoperative maladaptive behavioral changes ( Kotiniemi and Ryhanen, 1996 ). Although a history of previous surgery predicted increased incidence of postoperative maladaptive behavior in one study ( Lumley et al., 1993 ), other studies did not confirm this finding (Kain et al., 1996c ; Kotiniemi et al., 1997b ). It is likely that the quality of surgical experiences is an important predictor, not simply the history of surgery. Quality of past medical experience as a predictor of future anxiety of the child has been reported in studies exploring the issue of preoperative anxiety ( Kain et al., 1996c ).

Interventions

Preparation Programs

The impact of preparation programs on the incidence of postoperative behavioral changes is not clear. Vernon and Thompson (1993) completed a meta-analysis of published studies that evaluated the effects of preoperative behavioral preparation programs on postoperative behavior. The meta-analysis concluded that on the average, children who received preoperative interventions tended to have less postoperative maladaptive behavioral changes than did control subjects. In contrast, Kain et al. (1998a) compared several types of preoperative preparation programs in children and found no effect of preoperative preparation on the incidence of postoperative behavioral changes.

Parental Presence

The impact of parental presence during induction of anesthesia on the incidence of postoperative behavioral changes was evaluated ( Kain et al., 1996b ). To date, all studies concluded that the presence of a parent during induction does not have an impact on the issue of postoperative behavioral changes ( Kain et al., 1996b ; Kain, 2000 ).

Sedatives

Investigations that looked into the association between preoperative sedative premedication and postoperative behavioral changes report contradictory findings. Two investigations report some beneficial effects of premedication on postoperative behavior ( Padfield et al., 1986 ; Payne et al., 1992 ), but others report no effect ( Parnis et al., 1992 ). Furthermore, an investigation found a higher incidence of negative postoperative behavioral changes in children who were premedicated ( McGraw and Kendrick, 1998 ). These contradictory results may be explained by the methodologic complexity of this issue. Confounding variables such as age of child, surgical procedure, postoperative pain, and recent stressful major life events must be considered. An investigation by Kain and others (1999b) addressed all of these methodologic issues and screened all children for recent stressful life events. The investigators found that a significantly smaller number of children who were premedicated with oral midazolam before surgery presented with negative behavioral changes on postoperative days 1 through 7 ( Fig. 7-11 ). Postoperative behaviors that were most improved included apathy and withdrawal, separation anxiety, and eating disturbances. At postoperative week 2, however, there were no significant differences between the placebo and midazolam groups. Thus, it can be concluded that in addition to its significant beneficial preoperative effects, sedative premedication improves immediate postoperative behavioral outcomes in young children undergoing general anesthesia and outpatient surgery.

 
 

FIGURE 7-11  The effect of oral midazolam on the incidence of postoperative behavioral outcomes.  (Kain ZN, Mayes LC, Wang SM, Hofstader MB: Postoperative behavioral outcomes in children: effects of sedative premedication. Anesthesiology 90:758-65, 1999.)

 

 

 

▪ CLINICAL OUTCOMES

Five decades ago, Janis (1958) proposed that moderate levels of preoperative anxiety in adult patients were associated with good postoperative behavioral recovery and that low and high levels of preoperative anxiety were associated with poor behavioral recovery. Although Janis' theory is intriguing, his studies were based on descriptive data from nonrandom, limited samples and retrospective reports of questionable validity. Subsequent studies have been critical of Janis' methodology and have reported a linear rather than a curvilinear relationship between anxiety level and postoperative behavioral recovery ( Johnson et al., 1971 ; Johnston, 1980 ; Johnston and Carpenter, 1980 ; Newman, 1984 ; Pick et al., 1994 ). That is, low levels of preoperative anxiety are associated with good postoperative behavioral recovery, while high levels of preoperative anxiety are associated with poor postoperative recovery. To date, the adult literature indicates that intensity of pain, analgesic requirements, postsurgical complications, length of hospital stay, poor patient satisfaction, and blood cortisol levels have all been reported to be associated with high levels of preoperative anxiety ( Devine, 1992 ; Johnston and Vogele, 1993 ; Contrada et al., 1994 ; Kiecolt-Glaser et al., 1998 ).

Many reviews of this research have appeared that, although critical of the methodology of a large number of studies, concluded that high preoperative anxiety is associated with impaired postoperative recovery ( Mathews and Ridgeway, 1984 ; Mumford et al., 1982 ; Rogers and Reich, 1986 ; Anderson, 1987 ; Suls and Wan, 1989 ; Johnston and Wallace, 1990 ; Kincey and Saltmore, 1990 ; Devine, 1992 ;Johnston and Vogele, 1993 ; Contrada et al., 1994 ; Kiecolt-Glaser et al., 1998 ).

The fact that low preoperative anxiety is predictive of good postoperative outcome underlies many interventions in which the aim is to reduce preoperative anxiety. As with the cohort studies described earlier, preparation studies have used diverse postoperative outcome measures, including pain, analgesic requirements, length of hospital stays, patient satisfaction, cortisol levels, blood pressure, heart rate, and behavioral indices of recovery ( Mumford et al., 1982 ; Andersen and Masur, 1983 ; Mathews and Ridgeway, 1984 ; Anderson, 1987 ; Johnston and Vogele, 1993 ). Reviews of this research concluded that psychologically prepared adult patients have improved postoperative recovery ( Mumford et al., 1982 ; Suls and Wan, 1989 ; Johnston and Wallace, 1990 ; Devine, 1992 ; Johnston and Vogele, 1993 ;Contrada et al., 1994 ; Kiecolt-Glaser et al., 1998 ).

In contrast to the adult literature, there is a paucity of peer-reviewed, published outcome data regarding the question of whether heightened preoperative anxiety impairs postoperative recovery in children undergoing surgery. A large-scale study assessed this question with convergent clinical, neuroendocrinologic, and behavioral measures and found that increased preoperative anxiety in children is associated with impaired postoperative behavioral and clinical recovery. Analysis of the data indicated that children who were more anxious preoperatively showed poorer immediate clinical recovery ( Kain et al., 2002c ). The study also found a significant relationship between preoperative anxiety and postoperative pain and postoperative behavioral recovery. That is, children who were more anxious preoperatively were in more pain postoperatively and had a higher incidence of postoperative behavioral changes.

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Motoyama & Davis: Smith's Anesthesia for Infants and Children, 7th ed.

Copyright © 2005 Mosby, An Imprint of Elsevier

▪ SUMMARY

The perioperative period may be very stressful for the young child undergoing surgery. The fear and anxiety during this period are associated not only with immediate hardship to parents and children but also with outcomes such parental satisfaction and the postoperative behavioral and clinical recovery. Here, we described a variety of behavioral interventions that can and should be used for the management of anxiety during this time period. Although some interventions such as preparation programs are well established, others, such as parental presence, music, and acupuncture, are still under development. The individual clinician should have the knowledge of the risk factors, management, and outcome of this important clinical phenomenon.

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Motoyama & Davis: Smith's Anesthesia for Infants and Children, 7th ed.

Copyright © 2005 Mosby, An Imprint of Elsevier

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