3. Results
Our goal of reducing the number of post-Induction sedated LPs by 50% in pediatric ALL patients was met. During the three-month post-intervention period from 10/1/20 to 12/31/20, 37 out of 77 post-Induction LPs were performed with sedation (48.1%) compared to 59 out of 59 (100%) in the same patient group one year earlier (10/1/19 to 12/31/19) (Fig. 1). Inclusive of Induction LPs, the total number of LPs in the post-intervention period was 91. Additional patient information is shown in Table 1.
Process maps developed for both techniques demonstrated that unsedated LPs provided a more streamlined approach, involving 42 total steps instead of 53, and 6 non value-added steps versus 16. Similarly, observations of clinic visits for patients receiving sedated or unsedated LPs revealed substantial differences in clinic visit duration. Six sedated LP visits and five unsedated LP visits were observed. Clinical time (visit time related directly to patient care, excluding wait and transportation times) was, on average, more than twice as long (169 minutes compared to 83 minutes) for patients receiving sedated LPs instead of unsedated, primarily related to involvement of the anesthesia team (evaluation and recovery).
An additional factor related to optimizing the LP process for both the institution and for patients is the cancelling of sedated procedures. During the post-intervention period, 30% of scheduled sedated LPs were cancelled for reasons such as NPO violations, positive COVID-19 tests, and viral upper respiratory infections. Patients receiving unsedated LPs were not tested for COVID-19 and were able to proceed with their procedures if symptoms of mild respiratory infection were present.
Analysis of CSF characteristics obtained from LPs during the post-intervention period revealed a higher incidence of blood in the CSF (>500 RBCs) for unsedated procedures (5/43, 11.6%) as compared to sedated procedures (0/48, 0%) (Fig. 2). There were no failed LPs in either group.
Surveys were provided to 19 patients who received both types of LPs, and 16 were returned (response rate 84.2%). Patient and guardian preferences for unsedated vs sedated LPs (evaluated on a 0 to 10 scale, 10 indicating a strong preference for unsedated LPs) showed a mean response of 9.3 for guardians and 8.5 for patients (Fig. 3). 43% of guardians and 33% of patients indicated that COVID-19 testing requirements did not play a significant role in their responses (Fig. 4), suggesting that some might choose to continue with unsedated LPs even if COVID-19 testing was not required.
Finally, costs were approximated by comparing the overall charges to patients for sedated and unsedated LPs, and by assessing the cumulative opportunity cost of cancelled LPs. The average overall charges to a pediatric patient with ALL at the University of Iowa for a clinic visit involving a sedated LP, inclusive of labs, medications, involvement of the anesthesia team and use of recovery rooms, total $10,620.85 (average obtained from 6 observed sedated LPs). For a visit with an unsedated LP, the average overall charges total $4,884.69 (average obtained from 5 observed unsedated LPs). This results in a cost reduction of $5,736.16 per procedure. Extrapolating the total number of LPs performed during our post-intervention window, 91, to an entire year, provides an estimate of 364 LPs per year. If 50% of these are performed unsedated, there is an approximate health care expenditure reduction of $1,043,981 to pediatric patients with ALL per year. During the post-intervention period, 21 sedated LPs were cancelled. The average usage time of sedated procedure and recovery rooms per sedated LP was determined to be 91 minutes, and the total charges, including anesthesia team and recovery rooms, approximately $15,392.54. Extrapolating these numbers results in an opportunity cost of 128 hours and $1,290,000 per year to our institution.