Uncommon combinations of ICD10-PCS or ICD-9-CM operative procedure codes account for most inpatient surgery at half of Texas hospitals

Inhalational Agent Dosing Behaviors of Anesthesia Practitioners Cause Variability in End-Tidal Concentrations at the End of Surgery and Prolonged Times to Tracheal Extubation

INTRODUCTION

Prolonged times to tracheal extubation are intervals from the end of surgery to extubation ≥15 minutes. We examined why there are associations with the end-tidal inhalational agent concentration as a proportion of the age‑adjusted minimum alveolar concentration (MAC fraction) at the end of surgery.

METHODS

The retrospective cohort study used 11.7 years of data from one hospital. All p‑values were adjusted for multiple comparisons.

RESULTS

There was a greater odds of prolonged time to extubation if the anesthesia practitioner was a trainee (odds ratio 1.68) or had finished fewer than five cases with the surgeon during the preceding three years (odds ratio 1.12) (both P<0.0001). There was a greater risk of prolonged time to extubation if the MAC fraction was >0.4 at the end of surgery (odds ratio 2.66, P<0.0001). Anesthesia practitioners who were trainees and all practitioners who had finished fewer than five cases with the surgeon had greater mean MAC fractions at the end of surgery and had greater relative risks of the MAC fraction >0.4 at the end of surgery (all P<0.0001). The source for greater MAC fractions at the end of surgery was not greater MAC fractions throughout the anesthetic because the means during the case did not differ among groups. Rather, there was substantial variability of MAC fractions at the end of surgery among cases of the same anesthesia practitioner, with the mean (standard deviation) among practitioners of each practitioner's standard deviation being 0.35 (0.05) and the coefficient of variation being 71% (13%).

CONCLUSION

More prolonged extubations were associated with greater MAC fractions at the end of surgery. The cause of the large MAC fractions was the substantial variability of MAC fractions among cases of each practitioner at the end of surgery. That variability matches what was expected from earlier studies, both from variability among practitioners in their goals for the MAC fraction given at the start of surgical closure and from inadequate dynamic forecasting of the timing of when surgery would end. Future studies should examine how best to reduce prolonged extubations by using anesthesia machines' display of MAC fraction and feedback control of end-tidal agent concentration.

Case duration prediction and estimating time remaining in ongoing cases

In this issue of the British Journal of Anaesthesia, Jiao and colleagues applied a neural network model for surgical case durations to predict the operating room times remaining for ongoing anaesthetics. We review estimation of case durations before each case starts, showing why their scientific focus is useful. We also describe managerial epidemiology studies of historical data by the scheduled procedure or distinct combinations of scheduled procedures included in each surgical case. Most cases have few or no historical data for the scheduled procedures. Generalizability of observational results such as theirs, and automatic computer assisted clinical and managerial decision-making, are both facilitated by using structured vocabularies when analysing surgical procedures.

Similarities Between Pediatric and General Hospitals Based on Fundamental Attributes of Surgery Including Cases Per Surgeon Per Workday

Introduction

Operating room (OR) management decision-making at both pediatric and adult hospitals is determined, in large part, by the same fundamental attributes of surgery and other considerations related to case duration prediction. These include the non-preemptive nature of surgeries, wide prediction limits for case duration, and constraints to moving or resequencing cases on the day of surgery. Another attribute fundamentally affecting OR management is the median number of cases a surgeon performs on their OR days. Most adult surgeons have short lists of cases (i.e., one or two cases per day). Similarly, at adult hospitals, growth in caseloads is mostly due to the subset of those surgeons who also operate just once or twice per week. It is unknown if these characteristics of surgery apply to pediatric surgeons and pediatric hospitals as well.

Methods

Our retrospective cohort study included all elective surgical cases performed at the six pediatric hospitals in Florida during 2018 and 2019 (n = 71,340 cases). We calculated the percentages of combinations of surgeon, date, and hospital (lists) comprising one or two cases, or just one case, and determined if the values were statistically >50% (i.e., indicative of “most”). We determined if most of the growth in caseload and intraoperative work relative value units (wRVUs) at the pediatric hospitals between 2018 and 2019 accrued from low-caseload surgeons. Results are reported as mean ± standard error of the mean.

Results

Averaging among the six pediatric hospitals, the non-holiday weekday lists of most surgeons at each facility had just one or two elective cases, inpatient and/or ambulatory (68.1%; p = 0.016 vs. 50%, n = 27,557 lists). Growth in surgical caseloads from 2018 to 2019 was mostly attributable to surgeons who in 2018 averaged ≤2.0 cases per week (76.3% ± 5.4%, p = 0.0085 vs. 50%). Similarly, growth in wRVUs was mostly attributable to these low-caseload surgeons (73.8% ± 5.4%, p = 0.017 vs. 50%).

Conclusions

Like adult hospitals, most pediatric surgeons’ lists of cases consist of only one or two cases per day, with many lists containing a single case. Similarly, growth at pediatric hospitals accrued from low-caseload surgeons who performed one or two cases per week in the preceding year. These findings indicate that hospitals desiring to increase their surgical caseload should ensure that low-caseload surgeons are provided access to the OR schedule. Additionally, since percent-adjusted utilization and raw utilization cannot be accurately measured for low-caseload surgeons, neither metric should be used to allocate OR time to individual surgeons. Since most adult and pediatric surgeons have low caseloads, this is a fundamental attribute of surgery.

Visualization of aggregate perioperative data improves anesthesia case planning: A randomized, cross-over trial

STUDY OBJECTIVE

A challenge in reducing unwanted care variation is effectively managing the wide variety of performed surgical procedures. While an organization may perform thousands of types of cases, privacy and logistical constraints prevent review of previous cases to learn about prior practices. To bridge this gap, we developed a system for extracting key data from anesthesia records. Our objective was to determine whether usage of the system would improve case planning performance for anesthesia residents.

DESIGN

Randomized, cross-over trial.

SETTING

Vanderbilt University Medical Center.

MEASUREMENTS

We developed a web-based, data visualization tool for reviewing de-identified anesthesia records. First year anesthesia residents were recruited and performed simulated case planning tasks (e.g., selecting an anesthetic type) across six case scenarios using a randomized, cross-over design after a baseline assessment. An algorithm scored case planning performance based on care components selected by residents occurring frequently among prior anesthetics, which was scored on a 0-4 point scale. Linear mixed effects regression quantified the tool effect on the average performance score, adjusting for potential confounders.

MAIN RESULTS

We analyzed 516 survey questionnaires from 19 residents. The mean performance score was 2.55 ± SD 0.32. Utilization of the tool was associated with an average score improvement of 0.120 points (95% CI 0.060 to 0.179; p < 0.001). Additionally, a 0.055 point improvement due to the "learning effect" was observed from each assessment to the next (95% CI 0.034 to 0.077; p < 0.001). Assessment score was also significantly associated with specific case scenarios (p < 0.001).

CONCLUSIONS

This study demonstrated the feasibility of developing of a clinical data visualization system that aggregated key anesthetic information and found that the usage of tools modestly improved residents' performance in simulated case planning.

Importance of operating room case scheduling on analyses of observed reductions in surgical site infections from the purchase and installation of capital equipment in operating rooms

BACKGROUND

We review the impact of the consequences of operating room (OR) management decision making on power analyses for observational studies of surgical site infections (SSIs) among patients receiving care in ORs with interventions versus without interventions involving physical changes to ORs. Examples include ventilation systems, bactericidal lighting, and physical alterations to ORs.

METHODS

We performed a narrative review of operating room management and surgical site infection articles. We used 10-years of operating room data to estimate parameters for use in statistical power analyses.

RESULTS

Creating pivot tables or monthly control charts of SSI per case by OR and comparing among ORs with or without intervention is not recommended. This approach has low power to detect a difference in SSI rates among the ORs with or without the intervention. The reason is that appropriate OR case scheduling decision making causes risk factors for SSI to differ among ORs, even when stratifying by surgical specialty. Such risk factors include case duration, urgency, and American Society of Anesthesiologists' Physical Status. Instead, analyze SSI controlling for the OR, where the patient had surgery, and matching patients using these variables is preferable. With α = 0.05, 600 cases per OR, 5 intervention ORs, and 5 or 1 control patients for each intervention patient, reasonable power (≅94% or 78%, respectively) can be achieved to detect reductions (3.6% to 2.4%) in the incidence of SSI between ORs with or without the intervention.

CONCLUSIONS

By using this matched cohort design, the effect of the purchase and installation of capital equipment in ORs on SSI can be evaluated meaningfully.

Development and Validation of an Algorithm to Classify as Equivalent the Procedures in ICD-10-PCS That Differ Only by Laterality

BACKGROUND

The switch from International Classification of Diseases, Ninth Revision, Clinical Modification to International Classification of Diseases, Tenth Revision, Procedure Coding System (ICD-10-PCS) for coding of inpatient procedures in the United States increased the number of procedural codes more than 19-fold, in large part due to the addition of laterality. We examined ICD-10-PCS codes for pairs of mirror-image procedures that are surgically equivalent.

METHODS

We developed an algorithm in structured query language (SQL) to identify ICD-10-PCS codes differing only by laterality. We quantified the impact of laterality on the number of commonly performed major therapeutic procedures (ie, surgical diversity) using 2 quarters of discharge abstracts from Texas.

RESULTS

Of the 75,789 ICD-10-PCS codes from federal fiscal year 2017, 16,839 (22.3%) pairs differed only by laterality (with each pair contributing 2 codes). With the combining of equivalent codes, diversity in the state of Texas decreased from 78.2 to 74.1 operative procedures (95% confidence interval, 5.1 to -3.1; P < .001).

CONCLUSIONS

Our algorithm identifies ICD-10-PCS codes that differ only by laterality. However, laterality had a small effect on surgical diversity among major therapeutic procedures. Our SQL code and the lookup table will be useful for all US inpatient analyses of ICD-10-PCS surgical data, because combining procedures differing only by laterality will often be desired.

Time to recovery after general anesthesia at hospitals with and without a phase I post-anesthesia care unit: a historical cohort study

PURPOSE

There is little knowledge about how hospitals can best handle disruptions that reduce post-anesthesia care unit (PACU) capacity. Few hospitals in Japan have any PACU beds and instead have the anesthesiologists recover their patients in the operating room. We compared postoperative recovery times between a hospital with (University of Iowa) and without (Shin-yurigaoka General Hospital) a PACU.

METHODS

This historical cohort study included 16 successive patients undergoing laparoscopic gynecologic surgery with endotracheal intubation for general anesthesia, at each of the hospitals, and with the hours from OR entrance until the last surgical dressing applied ≥ two hours. Postoperative recovery times, defined as the end of surgery until leaving for the surgical ward, were compared between the hospitals.

RESULTS

The median [interquartile range] of recovery times was 112 [94-140] min at the University of Iowa and 22 [18-29] min at the Shin-yurigaoka General Hospital. Every studied patient at the University of Iowa had a longer recovery time than every such patient at Shin-yurigaoka General Hospital (Wilcoxon-Mann-Whitney, P < 0.001). The ratio of the mean recovery times was 4.90 (95% confidence interval [CI], 4.05 to 5.91; P < 0.001) and remained comparable after controlling for surgical duration (5.33; 95% CI, 3.66 to 7.76; P < 0.001). The anesthetics used in the Iowa hospital were a volatile agent, hydromorphone, ketorolac, and neostigmine compared with the Japanese hospital where bispectral index monitoring and target-controlled infusions of propofol, remifentanil, acetaminophen, and sugammadex were used.

CONCLUSIONS

This knowledge can be generally applied in situations at hospitals with regular PACU use when there are such large disruptions to PACU capacity that it is known before a case begins that the anesthesiologist likely will need to recover the patient (i.e., when there will not be an available PACU bed and/or nurse). The Japanese anesthesiologists have no PACU labour costs but likely greater anesthesia drug/monitor costs.

Discharges with surgical procedures performed less often than once per month per hospital account for two-thirds of hospital costs of inpatient surgery

STUDY OBJECTIVE

Most surgical discharges (54%) at the average hospital are for procedures performed no more often than once per month at that hospital. We hypothesized that such uncommon procedures would be associated with an even greater percentage of the total cost of performing all surgical procedures at that hospital.

DESIGN

Observational study.

SETTING

State of Texas hospital discharge abstract data: 4th quarter of 2015 and 1st quarter of 2016.

PATIENTS

Inpatients discharged with a major therapeutic ("operative") procedure.

MEASUREMENTS

For each of N=343 hospitals, counts of discharges, sums of lengths of stay (LOS), sums of diagnosis related group (DRG) case-mix weights, and sums of charges were obtained for each procedure or combination of procedures, classified by International Classification of Diseases version 10 Procedure Coding System (ICD-10-PCS). Each discharge was classified into 2 categories, uncommon versus not, defined as a procedure performed at most once per month versus those performed more often than once per month.

MAIN RESULTS

Major procedures performed at most once per month per hospital accounted for an average among hospitals of 68% of the total inpatient costs associated with all major therapeutic procedures. On average, the percentage of total costs associated with uncommon procedures was 26% greater than expected based on their share of total discharges (P<0.00001). Average percentage differences were insensitive to the endpoint, with similar results for the percentage of patient days and percentage of DRG case-mix weights.

CONCLUSIONS

Approximately 2/3rd (mean 68%) of inpatient costs among surgical patients can be attributed to procedures performed at most once per month per hospital. The finding that such uncommon procedures account for a large percentage of costs is important because methods of cost accounting by procedure are generally unsuitable for them.