Establishment of a pediatric surgery center: increasing anesthetic efficiency
Article Outline
Abstract
Study Objective: To examine whether the establishment of dedicated pediatric operating rooms (ORs) staffed exclusively by pediatric anesthesiologists has had a significant impact on anesthetic efficiency during surgery.
Study Design: Before and after design.
Setting: General and pediatric operating rooms at Yale-New Haven Hospital.
Measurements and Main Results: Using Operating Room Information System data (1991 to 1997), we examined whether the anesthesia-controlled time, the time it takes for induction and emergence of anesthesia of a selected surgical procedure (tonsillectomy and adenoidectomy), was affected by the change of practice from general to pediatric ORs. The average length of anesthesia induction decreased by 30% (p = 0.0007). Similarly, the average length of emergence from anesthesia decreased by 42% (p = 0.01) and anesthesia-controlled time decreased by 31% (p = 0.0008). Of particular importance is the decrease by 75% in the anesthesia-controlled time range (maximum-minimum).
Conclusions: The establishment of dedicated pediatric ORs resulted in significantly shorter anesthesia induction and emergence times. Furthermore, the decreased variability of anesthesia-controlled time may allow for better scheduling of surgical cases and for better surgeon and patient satisfaction.
Keywords: Anesthesia: efficiency, manpower, operations, personnel, children’s hospital, pediatrics
Introduction
The Accreditation Council for Graduate Medical Education (ACGME) recently recognized pediatric anesthesia as a subspecialty within the discipline of anesthesiology.1 Although some suggest that children should be cared for only by anesthesiologists with specialty training, little data exist to support this opinion. Studies have demonstrated that only children in high-risk groups (e.g., neonates and young infants), or children who undergo complex surgical procedures, are best cared for by anesthesiologists with special experience and/or training in pediatric anesthesia.2, 3 This finding is consistent with other reports that support concentration of high-risk specialty care in designated medical centers.4 In addition, data suggest that the most important factor affecting clinical outcome in low-risk children who require surgery is not the number of subspecialty-trained anesthesiologists on staff but the volume of pediatric cases performed.5 If the volume of pediatric surgical cases, as well as pediatric specialty training, can influence outcome, then consolidation of all pediatric anesthesia services into a single location staffed by specialty-trained pediatric anesthesiologists may affect a variety of operative outcomes. One such outcome may be anesthesia-controlled time (ACT),6 that is, the time needed for induction and emergence of anesthesia. With the opening of the Yale-New Haven Children’s Hospital in 1993, all pediatric (0 to 15 years) surgical cases, except ophthalmology cases, were consolidated in the Children’s Hospital Operating Rooms (CHOR) and staffed exclusively by fellowship-trained pediatric anesthesiologists.
We hypothesized that this change to dedicated care by specialty-trained anesthesiologists, as well as a consolidation of specialty cases and an increase in the number of pediatric cases per anesthesiologist, would have a significant impact on ACT.
Materials and methods
Prior to August 1993, all children undergoing surgery at Yale-New Haven Hospital (YNHH) were anesthetized in two (inpatient/outpatient) general operating room (OR) facilities by multiple anesthesiologists with varied training and experience with pediatric anesthesia. In August 1993, a Children’s Hospital was established adjacent to the adult facilities, and since then all patients under the age of 15 years undergo surgery in the CHOR. Anesthetic care is given by fellowship-trained pediatric anesthesiologists.
A computerized Operating Room Information System (ORIS) was introduced at YNHH in April 1992. This system contains case information, including patient demographics, designated anesthesiologist, type of anesthesia, surgeon, surgical procedure, and anesthesia and surgery times consistent with those defined by the Association of Anesthesia Clinical Directors.7 The information is entered into ORIS by the scheduling office of YNHH and by the nurse assigned to the individual OR, and contains data regarding all OR facilities at YNHH.
Using data from ORIS, we compared the duration of anesthesia induction and anesthesia emergence before (1992 to 1993) and after (1994 to 1997) the establishment of the CHOR. We defined anesthesia induction as the time from patient entrance into the OR until the patient is ready for surgical positioning or skin preparation; and anesthesia emergence as the time from the conclusion of the surgical procedure, including dressing, until the patient leaves the OR. Using Dexter et al.’s6 terminology, we have defined the sum of anesthesia induction and anesthesia emergence as ACT.
To control for possible confounding variables, such as changes in anesthetic practice during the years examined (e.g., the increased use of regional anesthesia for lower abdominal procedures or the introduction of the laryngeal mask airway), we chose to examine data from a single procedure for which the anesthetic and surgical technique has remained relatively unchanged during the study period. The surgical procedure chosen was tonsillectomy and adenoidectomy under age 12 [CPT 42820] and age 12 or over [CPT 42821]. We also examined whether there was a relationship between ACT and the number of an individual anesthesiologist’s cases (i.e., case volume), age of child, and American Society of Anesthesiologists (ASA) physical status.
Anesthesia-controlled time, induction time, and emergence time were compared using analysis of variance (ANOVA) with Scheffe’s correction for multiple comparisons. Correlations were examined using Pearson correlation coefficient (r). Data are presented as means ± SD or range (minimum-maximum). Statistical significance was assumed for p ≤ 0.05. Data were analyzed with SPSS version 6.1.1 software (SPSS Inc., Chicago, IL).
Results
After the opening of the Children’s Hospital, the number of anesthesiologists caring for children decreased from 21 to 8 (Table 1). Only two anesthesiologists from the initial group of 21 remain among the current members of the pediatric anesthesia section. The age of the child, ASA physical status, and surgical time did not change significantly during the years studied.
Table 1. Demographic Data Before and After the Establishment of the Children’s Hospital Operating Rooms
| Year | Cases (n) | Average Child’s Age (y) | Anesthesiologists (n) |
|---|---|---|---|
| 1992∗ | 89 | 6.7 ± 3.2 | 21 |
| 1993† | 80 | 6.3 ± 3.1 | 22 |
| 1994‡ | 137 | 6.0 ± 3.3 | 7 |
| 1995‡ | 168 | 6.1 ± 3.3 | 8 |
| 1996‡ | 138 | 5.9 ± 3.2 | 8 |
| 1997‡ | 204 | 5.5 ± 2.8 | 8 |
∗ Before opening of the Children’s hospital, data from May through December. |
† Before opening of the Children’s hospital, data from January through August 5th. |
‡ After the establishment of the Children’s Hospital, data from January through December. |
As can be seen from Table 2 anesthesia induction time decreased significantly in all years following the opening of the CHOR versus the pre-CHOR years (ANOVA; p = 0.0007). For example, the average length of anesthesia induction decreased by 30%, from 24 ± 6 minutes in 1992 to 1993 to 17 ± 3 minutes in 1997. The average time for anesthesia emergence also decreased significantly (ANOVA; p = 0.01). Average emergence decreased by 42%, from 16 ± 9 minutes in 1992/3 to 11 ± 2 minutes in 1997. Anesthesia-controlled time also decreased significantly in all years post-CHOR compared to pre-CHOR (ANOVA; p = 0.0008).
Table 2. Induction and Emergence Data
| Year | Surgical Time (min)‡, ∥ | Induction Time (min)∥, § | Emergence Time (min)∥, ¶ | Anesthesia Controlled Time g (min, range)∗∗, †† |
|---|---|---|---|---|
| 1992∗ | 41 ± 13 | 24 ± 6 | 13 ± 8 | 39 ± 10 (20–58) |
| 1993∗ | 40 ± 18 | 23 ± 7 | 19 ± 11 | 41 ± 13 (25–83) |
| 1994† | 39 ± 14 | 15 ± 4 | 16 ± 3 | 31 ± 5 (22–40) |
| 1995† | 41 ± 16 | 20 ± 4 | 13 ± 3 | 33 ± 6 (26–42) |
| 1996† | 38 ± 13 | 19 ± 3 | 12 ± 2 | 30 ± 3 (27–34) |
| 1997† | 37 ± 14 | 17 ± 3 | 11 ± 2 | 27 ± 4 (20–32) |
∗ Before opening of the Children’s Hospital. |
† After the establishment of the Children’s Hospital. |
‡ Surgical time is defined as time from surgical prep until procedure end. |
∥ Data are presented as Mean ± SD and range (min-max). |
§ ANOVA for induction time, p = 0.0007. |
¶ ANOVA for emergence time, p = 0.01. |
∗∗ Anesthesia control time = induction + emergence. |
†† ANOVA for anesthesia control time, p = 0.0008. |
Of importance is the significant decrease that occurred in the variability of ACT in the years post-CHOR as compared to the years pre-CHOR. Anesthesia-controlled time variability can be assessed by examining both the standard deviations of the induction and emergence times and the range [maximum − minimum = range] of the ACT (Figure 1A, 1B and Figure 2). The range of ACT decreased from 48 minutes in 1992 to 1993 to 12 minutes in 1997; this finding represents a decrease of 75%.
Figure 1.
Induction time, emergence time, and anesthesia-controlled time (ACT) for all anesthesiologists providing care for children prior to the establishment of specialized pediatric operating rooms in 1993 (A) and 1997 (B). Column number = total number of tonsillectomy and adenoidectomy cases for that anesthesiologist for the time period.
Figure 2.
Range of anesthesia-controlled time over the years of the study.
Finally, we found no significant correlation between ACT and the case volume, age, or ASA physical status of the child before or after the establishment of CHOR.
Discussion
To date, this is the first study to demonstrate that consolidation of pediatric patients into a separate facility staffed by specialty trained anesthesiologists can improve anesthetic efficiency. The establishment of the Yale-New Haven Children’s Hospital, with separate pediatric ORs and exclusive staffing by pediatric anesthesiologists, resulted in significantly shorter ACT accompanied by a significant reduction in ACT variability.
The results of this study may be of particular interest to general hospitals that are considering the establishment of a separate pediatric facility, or, more likely in these times, deciding to dismantle specialized care units such as pediatric operating suites. Although establishment and maintenance of specialized operating suites may be associated with additional costs, efficiency, as well as patient and surgeon satisfaction, may improve. Some practitioners may suggest that the decrease of 13 minutes in ACT that we demonstrated is not of significance if one considers other variables such as surgeon-controlled time and between-case time. We agree that the importance of our findings depends on the number of cases performed per room per day. The more cases that are done in an OR each day, the greater the chance that a decrease in ACT will result in a significant impact. For example, if one performs seven short/intermediate (i.e., tonsillectomy and adenoidectomy) procedures per room per day, the 13 minutes savings per case will amount to more than 1 hour of OR time, which is sufficient time to schedule an additional short case. In contrast, Dexter et al.6 suggested that a decrease in ACT cannot permit one additional surgical procedure to be reliably scheduled during the work day. This analysis, however, was performed on a model considering a variety of surgical procedures such as coronary artery bypass, herniorrhaphy, and total hip replacement, and may not be applicable to a model such as the one presented in this report.
It is also important to emphasize that the decreased variability in ACT may result in better patient and surgeon satisfaction. That is, decreased variability may allow for more accurate scheduling and a much higher likelihood that afternoon surgical cases will not be delayed. With the increasing competition for patients among hospitals and health maintenance organizations, institutions may be well served to have in place mechanisms that increase efficiency and thus satisfaction.
There are several possible reasons for the findings presented in this study. The creation of a separate group of fellowship-trained pediatric anesthesiologists with the opening of the CHOR significantly changed the pediatric experience among the anesthesiologists providing care to children. It is important to realize, however, that the case volume of each anesthesiologist also increased significantly with the opening of the Children’s Hospital from 2 (median for this procedure in 1992 to 1993; range 1 to 20) to 21 (median for this procedure in 1996 to 1997; range 9 to 58). Thus, the benefits may be from subspeciality training or dedication to subspeciality practice, or a combination of both.
The CHOR also are currently staffed by nursing and support personnel with specialty training and an interest in the care of children. While it is possible that this fact contributed to overall care of the children, we specifically chose to examine ACT, which is relatively independent of these factors and is assumed to be a good index of care delivered by the anesthesiologist. It is unlikely that a major change in anesthetic technique for tonsillectomy and adenoidectomy during this period affected the findings. The only significant change in practice relevant to this surgical procedure was the introduction of sevoflurane in late 1996, which conceivably could have affected only the final year of the study. It is interesting to note that this study methodology may allow for the examination of the effect of anesthetic drugs, such as sevoflurane, on anesthetic efficiency in future years at our institution.
The lack of correlation between induction and emergence length and ASA physical status and age of the children is not surprising considering the small range within these variables. The lack of a significant correlation between the case volume of individual anesthesiologists and induction and emergence times prior to the establishment of the CHOR is probably related to the very small case volume for most anesthesiologists. It would have been interesting to analyze the ACT data for the two anesthesiologists who were anesthetizing children before and after the establishment of the CHOR. Unfortunately, most tonsillectomy and adenoidectomy procedures in children were performed before the establishment of the CHOR in our general ambulatory surgery center and these two anesthesiologists were providing anesthetic care in the general inpatient surgical facility; therefore, this analysis could not be performed. Finally, a potential methodological limitation of this study must be noted. As we do not have data regarding ACT in other operating sites at Yale-New Haven Hospital, we cannot exclude the possibility that the decrease in ACT seen with the establishment of the pediatric surgery center is part of an overall institutional change. Based on personal observation, however, we do not believe that this is the case.
In conclusion, our findings demonstrate that a specialized care unit, a dedicated pediatric operating suite staffed with specialty-trained anesthesiologists, can significantly decrease anesthesia induction and emergence time. Furthermore, this reduction in time is associated with a decrease in the variability of total ACT. These shorter, less variable anesthetic times can potentially increase the predictability of case scheduling and have a major impact on overall OR efficiency and patient and surgeon satisfaction.
Acknowledgements
The authors would like to thank Paul G. Barash, MD, for his critical review of this manuscript.
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