Comparison of the success rates of the conventional approach, ultrasound-guided static and dynamic approach in LP procedure by simulation method

Objective: Lumbar puncture (LP) is one of the most commonly used procedures in pediatric and adult emergency departments. It is very important that this procedure can be performed quickly and successfully. Although it is a common procedure in emergency departments, the rate of successful LP is low and the rate of traumatic LP is high. Unsuccessful and/or traumatic LP may lead to complications such as misinterpretation of laboratory results, unnecessary antibiotic use, prolonged hospitalization, pain, hematoma, infection and nerve damage. Because of the serious complications that may occur, it is important that the LP procedure is performed successfully. There are some techniques used in routine practice during the LP procedure. These can be defined as conventional (traditional) method and techniques using ultrasound. Studies have shown that methods using ultrasound increase the success rate of LP in children and adults. In addition, these studies have shown that the ultrasound-assisted (static) method increases procedure speed, initial access success and patient comfort, and reduces the number of traumatic procedures and nerve damage. In the literature, there are mostly studies comparing the conventional method with the ultrasound-assisted (static) method. Studies on the use of ultrasound-guided (dynamic) method during LP procedure in adult patients are not available in the literature. In this study, we aimed to investigate whether the ultrasound-guided (dynamic) method used during the LP procedure performed by emergency medicine research assistants (ATAG) on a lumbar puncture model (LPM) is superior to the conventional and ultrasound-assisted (static) method in terms of LP success. Materials and methods: The 24 ATAGs included in the study were trained in LP by an emergency medicine specialist who has competence in basic and advanced ultrasonography and has a trainer identity, both theoretically and with different methods (KY, UYSY, UKDY) with bedside practice. Then, LPM was created and standardized by us. Volunteer participants were asked to perform LP on the LPM with KY, UYSY and UKDY. The LP procedure started with the determination of the intervertebral space and ended with the complete removal of the spinal needle from the LPM. The success of the procedure, success of the first entry, speed of the procedure (seconds), number of traumatic procedures and the presence or absence of complications were noted by the researcher. Each practitioner was allowed two attempts. Complete exit of the needle after its entry into the model was considered as one attempt. Guiding the needle inside was not considered as an additional intervention. The success of the procedure was evaluated according to whether or not saline (SF) representing CSF was obtained from the needle. If SF could not be obtained after two attempts, the procedure was considered unsuccessful. Obtaining SF in any of the two procedures was considered successful. Obtaining SF in the first attempt was considered as the first entry success. The duration of the procedure was monitored and recorded by the researcher using a stopwatch. The time was started when the practitioner stood at the model and started to use either palpation or ultrasound to find the appropriate vertebral space. The time elapsed after needle insertion and successful or unsuccessful procedure was also recorded. Any leakage of SF, representing CSF, through the LPM and/or damage to the needle during the procedure was considered a complication. The ATAG was reprocessed one week after they received LP training and performed their first procedure on the LPM. Which practitioner would use which method in which order was determined again through a computer-based randomization program. Data were collected and recorded similarly to the previous procedures. At the end of the study, LP success rate, initial access success rate, number of accesses, procedure duration, number of traumatic procedures and complication rate were evaluated. In addition, the data obtained after repeated procedures one week later were compared with the data of the first group. Here, the effect of post-training practice on success in subsequent repeat procedures was evaluated. At the end of the study, a questionnaire was applied to the practitioners. Their opinions about the study were asked. Results: Of the 24 participants, 9 were female (27.5%) and 15 were male (62.5%). The median age of the 24 participants was 27.5 years (27-28). The duration of residency of 24 participants was <1 year 9 (37.5%) and ≥ 1 year 15 (62.5%). Among the 24 participants, 10 (42.7%) had performed ≥ 5 LP procedures and 14 (53.7%) had performed < 5 LP procedures. The primary endpoint of our study was the success rate. 24 ATAGs performed 20 successful LP procedures with UKDY in the first procedure (p=0.514). In the second procedure, 21 successful procedures were performed (p=0.692). There was no significant difference in success between other methods and UKDY in the first and second procedures. There was also no statistical significance in the increased success rate in the second procedure (p=0.833). In terms of initial access success, 15 procedures in the first procedure and 17 procedures in the second procedure resulted in initial access success. No statistical significance was found in terms of first access success in both procedures. When the increased first access success in the second procedure was evaluated between the two procedures, no statistical significance was found (p=0.166). In both the first and second procedures, the method with a higher number of accesses was UKDY. However, there was no statistical significance. Although the number of accesses decreased in the second procedure, there was no statistical significance in the decrease in the number of accesses when the first and second procedures were compared (p=0.317). In the first and second procedures, the procedure speed was the slowest in seconds (median time 177.5 vs. 165.5). Although there was a decrease in procedure speed in the second procedure, there was no statistical significance (p=0.308). In terms of the number of traumatic procedures, 9 traumatic LPs were recorded in the first procedure and 7 traumatic LPs in the second procedure in UKDY. When the two procedures were compared, the decrease in the number of traumatic procedures was statistically significant (p=0.034). However, there was no statistically significant difference in the rate of traumatic procedures between the first and second procedures. There were 2 complications in the first procedure and 1 complication in the second procedure using UKDY. However, no statistical significance was found when compared with other methods. There was no statistical significance between the 3 methods in terms of success rates. In terms of initial access success, UYSY was statistically more successful in the first procedure (p=0.042). However, there was no difference between the two procedures. In terms of the number of accesses, UYSY provided a successful procedure with fewer accesses during the first procedure (p=0.042). However, there was no significant difference between the first and second procedure. KY was the fastest method among all methods (p<0.005). When the methods using USG were compared, UYSY was faster (p<0.005). No statistical significance was found between the methods in terms of traumatic procedure and complication rates. As a result of the comparison between the methods according to the seniority (≥1 year of practice) and juniority (<1 year of practice) of the practitioners; senior residents had a higher first access success rate in LP procedures performed with IMSI at the end of the first procedure (p=0.042). Senior residents successfully performed the first LP procedure with KY with a lower number of accesses (p=0.042). When the median procedure speed was analyzed, senior residents performed the LP procedure faster in both HF (p<0.005) and IMSY (p<0.005). In addition, they performed the second procedure significantly faster in HF and NICU (p<0.005). According to the results of the post-study questionnaire, the ATAG who participated in the study found the LP and USG training given before the study useful and stated that their self-confidence increased in terms of LP procedure after receiving training and performing the study on LPM. Conclusion: Of the three methods used during LP procedure, there was no statistical difference in the success rate, initial access success, number of accesses, procedural speed, traumatic procedure rate and complication rate in procedures performed with UKDY compared to procedures performed with KY and UYSY. However, we inferred from our data that the use of real-time USG during LP procedure is a difficult and time-consuming method. Therefore, we do not recommend this time-consuming and difficult technique in a clinic such as the emergency department where rapid and accurate diagnosis and treatment are required. We think that the technique can be improved and statistically stronger results can be obtained with more comprehensive and larger sample size studies in the future. Keywords: LP, conventional method, static ultrasound, dynamic ultrasound, simulation, lumbar puncture model