In human medicine, standard of care recommends an anesthesiologist or certified registered nurse anesthetist meet with patients prior to elective surgery to perform a PAC.1 In nonverbal patients such as young children, the PAC takes place between a legal guardian and the anesthesiologist or anesthetist. Performance of a PAC has been associated with positive outcomes. Positive outcomes include increased hospital revenue resulting from fewer day-of-surgery cancellations or delays, decreased patient anxiety, reduction in excessive preoperative testing and associated costs, increased preparedness of surgery and anesthesia staff and better optimization of hospital resources, increased awareness of concomitant diseases and medications affecting anesthesia, better prediction of perianesthetic complications, fewer adverse events, lower postoperative pain scores, and improved patient outcomes and patient satisfaction.1–15 Medical facilities in many industrialized nations use PACs. In France, a PAC is required by law and must precede elective surgery by ≥ 48 hours.9 According to the most recent practice advisory guidelines of the American Society of Anesthesiologists, for patients undergoing procedures with a medium to high degree of surgical invasiveness, the PAC should be performed ≥ 1 day prior to surgery.1
In North America, diplomates of the ACVAA are recognized by the AVMA as specialists in veterinary anesthesiology.16 Most ACVAA diplomates are employed by colleges and schools of veterinary medicine and perform clinical work in teaching hospitals. The authors consider it likely that most veterinary anesthesiologists do not routinely perform PACs with owners of animals prior to anesthesia, and to the authors’ knowledge, no studies have been performed to assess whether performing a PAC is associated with patient outcomes or client satisfaction in veterinary medicine.
The purpose of the study reported here was to assess client perceptions of the value of veterinary anesthesiologist involvement with anesthesia and pain management, the benefits of a PAC, and quality of care for dogs undergoing elective surgery for orthopedic disease. We specifically wanted to determine whether perceptions about quality of care would differ between dog owners who did and did not participate in a PAC with a veterinary anesthesiologist and whether these individuals would indicate a willingness to incur additional costs to ensure an anesthesiologist was involved in their pet's care. We hypothesized that, when surveyed, a greater proportion of clients who participated in a PAC with a veterinary anesthesiologist would express a high degree of satisfaction with their pet's quality of care and would strongly agree that they were willing to incur additional costs for care provided by an anesthesiologist, compared with clients who did not participate in a PAC.
Materials and Methods
The study was approved by the University of Illinois Internal Review Board (protocol No. 12275) for human research and was performed between December 15, 2011, and December 15, 2015. Study participation was voluntary, and informed consent was obtained from all participants prior to enrollment in the study. Owners of dogs undergoing evaluation for surgery to treat orthopedic disease of the stifle joint were eligible for study inclusion. To be considered for enrollment, a client was required to own a dog with any stifle joint disease that was evaluated for surgical correction during the study period. Disease could be unilateral or bilateral and acute or chronic, and patients could be receiving any medication. Owners of dogs with concomitant diseases were included, as long as the dog had an American Society of Anesthesiologists physical status of I (normal healthy patient) or II (mild systemic disease). Only clients who elected surgical treatment for their dog after it was recommended and agreed to participate in the study were included. Individuals whose dogs had previously undergone anesthesia and surgery, including those whose dogs had previous surgical treatment for stifle joint disease, were included. Individuals who were known to the hospital staff or employed at the hospital where the study was performed were excluded.
The study client population was selected to standardize groups according to American Society of Anesthesiologists physical status classification of the dogs and the planned anesthetic protocols for the dogs. Clients were randomly assigned to control or PAC groups by use of a random number generator.a
Clients in the PAC group had a PAC with an ACVAA diplomate after consultation with a surgery faculty member or resident to discuss the surgical procedure, surgical complications, and associated costs. Clients in the control group did not have a PAC after discussing the procedure with the surgeon. All study participants were asked to complete a 12-question survey.
PACs
All interactions with clients took place in a hospital examination room. Surgeons and surgery residents were blinded to the purpose of the study but were informed that clients would participate in a brief survey. Because of this, surgeons and surgery residents could not be prohibited from discussing anesthesia as part of their presurgical conversation with the client. The PACs were performed by 1 of 3 ACVAA diplomates (2 study authors [SCC-P and BLF] and 1 other individual) in the presence of another clinician (AEM) when it was convenient for the anesthesiologist (depending on the clinical schedule). These consultations varied in duration but typically lasted 10 minutes and occurred at any time prior to surgery. The ACVAA diplomate provided information about the anesthesia specialty and discussed pertinent information regarding the dog's anesthetic care with the client. Topics discussed during the PAC were not offered in any specific order, and the nature of the conversation was left unstructured to permit the anesthesiologist to tailor the consultation to the specific client and pet. However, prior to the first PAC, the 3 ACVAA diplomates met and drafted a list of topics that should be discussed with dog owners. These topics included a discussion with the pet owner on the role of the ACVAA in veterinary medicine and the training required to achieve diplomate status, the role of an anesthesiologist in veterinary specialty care, how a dog is monitored during the anesthetic period, equipment that might be used, how epidural anesthesia is performed, that the dog might have its hair clipped for the procedure, and how analgesia would be provided and signs of pain managed. The ACVAA diplomates did not use a formal checklist during the PAC; however, the clinician who was present during every PAC ensured that no essential items on this list were missed. At the conclusion of the PAC, owners were asked if they had any additional questions or concerns and were provided with the name of the anesthesiologist who performed the PAC and a phone number to use for contacting the anesthesiologist if additional questions or concerns arose regarding anesthesia or pain management. The clinician who was present during all PACs obtained informed consent for study participation, provided the hard copy survey to the owner, and instructed the owner on completion and submittal of the survey. Each owner submitted the survey in a sealed envelope to a client services representative before leaving the building.
Survey design
To assess client attitudes about the PACs, 2 surveys were used (1 for the PAC group and 1 for the control group). The surveys were created by the authors for purposes of the study and were not pilot tested prior to use. Each survey consisted of 12 statements, and participants were instructed to respond to each statement by circling 1 choice on a 5-point Likert-type scale17 as follows: 1 = strongly agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = strongly disagree. The 2 surveys were identical except that 2 statements had different wording, depending on whether the respondent had participated in a PAC.
Statements in the PAC group survey indicated that the client was very satisfied with the quality of care for the pet on the day of the survey and with the overall experience at the hospital. Other statements indicated that meeting with the anesthesiologist was beneficial, the anesthesiologist had answered all of the owner's questions about anesthesia and pain management for the pet, the owner was more comfortable knowing the surgery would be performed at a hospital with a veterinary anesthesiologist on staff, the owner knew who would perform the anesthesia procedure and what safeguards would be used to provide the safest anesthesia possible, and the owner would be willing to pay more for the surgery if it would guarantee anesthesia and pain management would be supervised by a veterinary anesthesiologist. One statement expressed owner anxiety about the surgery. More general statements indicated that veterinary specialty hospitals should have a veterinary anesthesiologist on staff and that meeting with an anesthesiologist before surgery should be part of the standard of care. Two distractor statements were also included: one indicated that the hospital appeared clean and well maintained, and the other indicated the pet was considered a member of the family. A section at the end of the survey was available for written comments. The text field responses were qualitatively and quantitatively assessed by 1 author (AEM).
For the control group survey, 10 of the 12 items were identical to those in the PAC group survey. The statement that meeting with the anesthesiologist was beneficial was revised to indicate that the owner would have found it beneficial to meet with an anesthesiologist and discuss anesthesia and pain management options, and the statement that the anesthesiologist had answered all questions about pain management and anesthesia was replaced with a statement indicating the owner had questions on these subjects that were not addressed. Because the latter statement was negatively worded, those response scores were reversed for purposes of comparison between groups.
Owner anonymity was preserved during tabulation of survey responses. Psychometric testing for validity was not performed.
Statistical analysis
Initial sample size was calculated with assumed values of p1 and p2, where p1 and p2 are the response proportions in the control and PAC groups. A constant difference of p2 — p1 ≥ 0.3, or equivalently an OR ≥ 3.5, was maintained, with α = 0.05 for a 2-sided test and power = 0.8. Because power and sample size vary with p1 and p2, we estimated a range of sample sizes starting with p1 = 0.25 and p2 = 0.55, with increases of both by increments of 0.05 up to p2 = 0.9. We determined that 50 participants/group met our desired α and power goals.
We defined each participant's survey score as the sum of the natural logarithms (ln) of the 12 statements. To determine whether parametric analysis was appropriate, the distributions of scores in the control and PAC groups were assessed visually with normal probability plots and quantitatively by the Shapiro-Wilk and Anderson-Darling tests; the results indicated nonnormal (non-Gaussian) distributions. For each survey item in each group, exponentiation of the ln-transformed Likert scores for the 50th percentile and its 95% CI gave the median and 95% CI for the survey item. The frequency distributions of scores for each survey item were compared between the 2 groups with the nonparametric Somers D test of ordinal association. Scale reliability18 was determined by calculation of the Cronbach α. The numeric value of α increases with the number of items on the scale and with reverse-scored items.17 Specific acceptance criteria and interpretation of α depend on the internal consistency of the scale and the use of the data.18 Statistical analyses were performed with commercially available software.b,c Values of P < 0.05 were considered significant for all statistical comparisons.
Results
One hundred fifty-five owners of dogs evaluated for surgical correction during the study period were known not to meet the inclusion criteria (ie, the dog did not undergo surgery), and 1 individual was excluded because of affiliation with the hospital and the study authors. However, the total number of clients assessed for eligibility and the number excluded for other reasons were not specifically tracked. Eighty clients were enrolled in the study; enrollment was halted when 40 surveys were collected for each group because there was adequate statistical power (> 0.8; α = 0.05) and the intended time frame for the study (4 years) was exceeded. Seventy-eight of 80 (98%) surveys were fully completed, and 2 surveys in the control group were incomplete (1 client did not respond to 5 items, and 1 did not respond to 2 items; these individuals’ responses to the remaining items were included in the analyses). The medians and 95% CI scores for each survey item were summarized (Table 1).
Median (95% CI) scores (antilog of natural logarithm-transformed scores used in the analyses) for statements in a survey of dog owners who did (n = 40) or did not (40) have a PAC with an anesthesiologist prior to their dogs’ stifle joint surgery (PAC and control groups, respectively) between December 15, 2011, and December 15, 2015.
| Item | Statement | PAC | Control | P value |
|---|---|---|---|---|
| 1 | I am very satisfied with the overall quality of care my pet received today. | 1.01 (0.98-1.05) | 1.14 (1.02-1.26) | 0.14 |
| 2 | The hospital appeared clean and well taken care of. | 1.20 (1.09-1.33) | 1.27 (1.11-1.46) | 0.84 |
| 3 | It was beneficial to meet with an anesthesiologist prior to my pet's surgery.* | 1.21 (1.08-1.35) | 2.15 (1.82-2.55) | < 0.001 |
| I would have found it beneficial to have met with an anesthesiologist prior to my pet's surgery to discuss my pet's anesthesia and pain management options.† | ||||
| 4 | The anesthesiologist answered all of my questions about my pet's anesthesia and pain management plan.* | 1.07 (1.00-1.14) | 1.44 (1.22-1.70) | < 0.001 |
| I have questions that I felt were not addressed about my pet's anesthesia and pain management plan.†‡ | ||||
| 5 | I am more comfortable knowing that my pet will have surgery at a hospital with a veterinary anesthesiologist on staff. | 1.10 (1.01-1.19) | 1.11 (1.02-1.20) | 0.78 |
| 6 | I know who will be providing the anesthesia for my pet and what safeguards will be taken to ensure the safest anesthesia possible will be provided during surgery. | 1.11 (1.02-1.20) | 1.83 (1.53-2.19) | < 0.001 |
| 7 | Veterinary specialty hospitals should have a veterinary anesthesiologist on staff similar to human hospitals. | 1.16 (1.05-1.27) | 1.48 (1.28-1.70) | 0.004 |
| 8 | Overall, I am very satisfied with my experience at this hospital. | 1.07 (1.00-1.14) | 1.12 (1.02-1.22) | 0.49 |
| 9 | I am willing to pay more for my pet's surgery if I knew it would guarantee that the anesthesia and pain management would be supervised by a veterinary anesthesiologist. | 1.34 (1.16-1.55) | 1.70 (1.48-1.96) | 0.01 |
| 10 | In human medicine, it is standard of care to meet with an anesthesiologist prior to surgery. I believe this should also be standard of care in veterinary medicine. | 1.25 (1.12-1.40) | 1.77 (1.51-2.06) | < 0.001 |
| 11 | My pet is a member of the family. | 1.05 (0.98-1.11) | 1.07 (1.00-1.15) | 0.43 |
| 12 | I have anxiety about my pet's surgery. | 1.71 (1.46-1.99) | 1.63 (1.40-1.90) | 0.65 |
Participants scored each statement on a Likert-type scale of 1 through 5, where 1 = strongly agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = strongly disagree. Seven data points were missing (1 client did not score items 11 and 12, and 1 did not score items 3, 4, 6, 11, and 12 [both were control group participants]). Univariate P values are shown for the difference between groups. Values of P < 0.05 were considered significant.
Statement included only on the PAC group survey.
Statement included only on the control group survey.
Responses for the control group were reverse scored for this item to allow intergroup comparison because the statement was negatively worded.
Scale reliability for the 78 completed surveys from both groups for the normal (ie, unscaled) Cronbach α was 0.77. The scale reliability values for the PAC group (α = 0.79) and for the control group (α = 0.68) were larger than the common acceptance guideline (α > 0.6).18
The proportion of clients in the PAC group who strongly agreed that meeting with an anesthesiologist prior to surgery was of benefit was greater (P < 0.05) than that of the control group. Similarly, clients of the PAC group were more likely to strongly agree that all their questions about the pet's anesthesia and pain management plan were answered than were members of the control group (on the basis of reverse scoring for the statement in the control survey that the client still had unanswered questions on this subject). Compared with the control group, the PAC group was more likely to strongly agree with statements indicating they knew who would perform the anesthesia procedure and what safeguards were in place, that veterinary specialty hospitals should have a veterinary anesthesiologist on staff, that they would be willing to pay more for the surgery if they knew it would guarantee anesthesia and pain management would be supervised by a veterinary anesthesiologist, and that meeting with an anesthesiologist prior to surgery is standard of care in human medicine and should be standard of care in veterinary medicine. Results for the remaining 6 statements did not differ between groups.
Most (79/80 [99%]) clients agreed or strongly agreed that they were very satisfied with the care their pet received on the day of the survey, and 79 of 80 (99%) agreed or strongly agreed that, overall, they were very satisfied with their experience at the hospital. In response to the distractor items, 40 of 40 (100%) clients in the PAC group and 37 of 40 (93%) in the control group agreed or strongly agreed that the hospital appeared clean and well taken care of, and 38 of 40 (95%) clients in each group strongly agreed that their pet was a member of the family. Fifty-five of 80 (69%) clients included comments on their survey. Most (43/55 [78%]) of these comments reflected the client's anxiety about their pet's surgery or anesthesia, and 8 (15%) cited concerns specifically about the recovery period and pain management. Sixteen of 55 (29%) comments reflected the clients’ feelings about the pet as a member of the family. There was no qualitative difference in the nature of comments between groups. None of the clients contacted an anesthesiologist after completing the survey.
Discussion
In the present study, we compared perceptions related to veterinary anesthesiologist involvement with anesthesia and pain management, the benefits of having a PAC with an anesthesiologist, and quality of patient care between clients who did and did not participate in a PAC prior to their dogs’ elective orthopedic surgery. Dog owners who participated in a PAC with an anesthesiologist were more likely to strongly agree that meeting with an anesthesiologist was beneficial and that they were willing to pay more to have an anesthesiologist supervise their pet's anesthesia and pain management than were owners who did not participate in a PAC. Clients who participated in a PAC were more likely to strongly agree that all their questions about these procedures had been answered, that they understood which measures would be taken to ensure their pet had the safest anesthesia possible, and that these procedures should be supervised by veterinary anesthesiologists in a veterinary specialty hospital than were those who did not (the control group). These findings indicated that participating in a PAC was associated with more positive perceptions of anesthesiologists and owner knowledge about the pet's anesthesia plan. The human medical literature indicates that having a PAC increases a patient's education regarding perianesthetic events and the role of anesthesiologists in the medical care team.15 Without a PAC, patients may not understand the role of an anesthesiologist during surgery or comprehend the difference between specialists in anesthesiology versus general practitioners.19 In our study, clients who participated in a PAC were significantly more likely to strongly agree that a PAC with an anesthesiologist should be standard of care in veterinary medicine than were clients of the control group.
Despite these findings, the data did not support that clients who participated in a PAC were more likely to strongly agree with the statement that they were very satisfied with their pet's quality of care than members of the control group, and thus we rejected the related hypothesis. There were several possible reasons for this finding. First, if all clients had a high degree of satisfaction with the overall quality of care and their experience at the facility, only a small subset would be likely to feel more satisfied after a PAC. Second, clients taking their pets to a tertiary veterinary care center may already have had preconceived opinions on the quality of care their pets would receive on the basis of interactions with primary care veterinarians, internet reviews, word-of-mouth reports, or their own prior experiences. For example, control group clients may have understood or expected that an anesthesiologist would be present during surgery at this type of facility.
Another item for which responses did not differ between groups concerned clients’ self-reported anxiety about the surgery. However, this finding was complicated by the fact that the wording of the statement was related to the surgery and did not specifically ask about anxiety related to anesthesia or pain management. Because of this, we could not determine whether clients who had a PAC felt less anxiety about these aspects of patient care than the control group. Results of studies in human medicine have indicated that a PAC either decreased patient anxiety20 or had no effect21; preoperative education by specially trained nurses was also shown to decrease anxiety of human surgical patients.22 To our knowledge, there are no reports of PACs causing increased patient anxiety in human or veterinary medicine.
The only survey item specifically related to anesthesia that did not differ between groups was the statement that the client was more comfortable knowing his or her pet would have surgery at a hospital with a veterinary anesthesiologist on staff. We suspected this result occurred because the statement was nonspecific regarding anesthesia and anesthesiologists. It may also have reflected that in our study population, regardless of whether they had a PAC, clients had a positive attitude toward anesthesiologists and the care they may provide.
The present study had limitations related to PAC design, survey design and language, and the studied population. The survey used in this study was not validated, and therefore important domains could have been missed. Tests for reliability, face and content validity, and repeatability were not performed. It is useful to validate or pretest a survey prior to routine use to identify problems and bias that may affect results.23 Item testing can sometimes be omitted when previous validated questionnaire statements or questions are used.24 However, we were unable to identify previous questionnaires to use that covered the topics of interest. Nevertheless, information obtained in the study could be used to inform a larger, more comprehensive future study. Response bias that can occur with surveys of this design include acquiescence, demand characteristics, extreme responding, and respondent fatigue. Acquiescence describes respondent agreement with self-report items.25 It is possible that this phenomenon occurred during our study and clients wanted to be agreeable with the statements on the survey. Demand characteristics describe a situation in which the respondent tries to identify the hypothesis of the study and conforms to that presumed hypothesis to support the researcher.26 Extreme responding occurs when a subject mostly selects extreme responses (eg, scores of 1 [strongly agree] or 5 [strongly disagree] on a 5-point Likert-type scale).d Respondent fatigue occurs when a respondent tires after responding to a certain number of survey items and can lead respondents to provide low-quality responses to survey items.27
Limitations of the survey language for some statements constrained the conclusions that could be drawn for the present study. Two items were worded differently for the PAC and control groups because their experiences differed. A statement on the PAC group survey that the anesthesiologist had answered all questions about pain management and anesthesia was replaced on the control group survey with a statement indicating the owner had questions on these subjects that were not addressed, and responses on the latter survey were reverse scored for purposes of the analysis. Colosi28 reported that negatively worded questions can cause confusion and that reversed scores for negatively worded questions yield a different distribution than scores for positively worded questions.
Our survey included 2 statements regarding client satisfaction because one of the aims of the study was to determine whether participating in a PAC influences this variable. The response distributions for each of these statements were similar between groups. Whether a survey should include repeated items on the same topic is debated in the field of social sciences survey research. Researchers who support the domain sampling theory argue that to obtain the most authentic information from a respondent, asking the same question in many different ways helps to avoid various types of systemic and random error within a survey study.29
Two survey items unrelated to the study purpose were included as distractors to assess whether control and PAC group participants had comparable attitudes on other subjects. The distractor items were related to perceptions that the hospital appeared clean and well cared for and that the pet was considered a member of the family. We included these items in the survey because we considered it possible that clients who did not find the hospital clean or did not consider their pet a member of their family would respond to the other survey statements in a more negative manner. Nearly all respondents strongly agreed or agreed the hospital was clean (77/80 [96%]) and that their pet was a member of their family (76/80 [95%]). Thus, the respondents’ scoring of these items did not correspond to their responses to the items specifically focused on anesthesia (which generally differed between groups).
Owing to the design of the survey, socioeconomic status, age, religion, race, ethnicity, gender, educational level, marital status, number of pets, whether the pet being evaluated or other pets owned by the client had previously undergone surgery, and other potentially relevant respondent data were not collected. Therefore, it was unknown whether demographics or past experiences were associated with responses of either group. We also did not investigate the extent of additional cost that clients would have been willing to incur to have an anesthesiologist supervise their pet's anesthesia and pain management, and it might be beneficial to attempt to quantify this in a future study.
Studies in human medicine have revealed that patients of certain demographic groups require alterations in the traditional PAC to maximize benefits. For example, anesthesiologists performing PACs with patients whose religious beliefs prohibit the use of blood transfusions have unique challenges.30 Other human medical studies have found that patients with low education levels are less likely to understand the role of an anesthesiologist than those with higher education levels and therefore may require additional consultation time.31 Information obtained in the present study may be useful in refining future survey-based studies of, and information given to, owners of animals undergoing elective surgery. Investigations are warranted to determine whether differences in client demographics, past experiences, and species of the pet influence client perceptions of anesthesia and pain management practices, quality of care, and the benefits of a PAC in veterinary medical settings.
Acknowledgments
No external funding was provided for this study. The authors reported no conflicts of interest.
ABBREVIATIONS
| ACVAA | American College of Veterinary Anesthesia and Analgesia |
| CI | Confidence interval |
| PAC | Preanesthetic consultation |
Footnotes
Randomness and Integrity Services Ltd, Dublin, Ireland.
CTTITEM, SAS, version 9.3, SAS Institute Inc, Cary, NC.
SAS, version 9.3, SAS Institute Inc, Cary, NC.
Batchelor, JH, Miao C, McDaniel M. Extreme response style: a meta-analysis (oral presentation). 28th Annu Conf Soc Ind Organ Psychol, Houston, Tex, April 2013. Available at: www.people.vcu.edu/~mamcdani/Publications/Batchelor,%20Miao%20&%20McDaniel%20(2013,%20April)%20extreme%20responding.pdf. Accessed Feb 7, 2019.
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