gms | German Medical Science

Objective: In our previous study we have demonstrated that the optimal time window for cortical mapping in a Sleep-Awake-Awake (S-A-A) craniotomy might begin 20 minutes after extubation of the Patient, however the assessment of time window beyond 40 minutes after extubation was not possible due to the lack of data. During the last year we have accumulated additional data in order to assess a longer intraoperative time window. Moreover, in cooperation with Tata Memorial Hospital in Mumbai, India, we have acquired the data about intraoperative reaction speed during Awake-Awake-Awake (A-A-A) craniotomy.

Methods: Reaction speed was assessed in 62 Patients in S-A-A and 18 Patients in A-A-A group. Pathology operated was primary or metastatic brain tumors. All patients in S-A-A Group underwent surgery following a "Sleep-Awake-Awake" protocol, whereas patients in A-A-A group underwent "Awake-Awake-Awake" anesthesia protocol. The registration was done with an application Reaction Time Sampler in both groups. Reaction times were determined at least once every 10 minutes. Reaction time determination was performed in parallel with our standard methods for evaluation of language and cognitive functions. Statistical analysis was performed using SPSS v24.0 (IBM, New York, U.S.).

Results: The data is presented as mean ± standard deviation. The preoperative response times of S-A-A patient cohort (574 ± 116ms) were significantly shorter than those measured during surgery (810 ± 75ms; p<0,001). No factors correlated with intraoperative reaction speed. Patient age was the only factor that correlated with the preoperative reaction speed in S-A-A cohort, r=.562, p 60 minutes after extubation. In the A-A-A cohort, the difference between the pre- and intraoperative reaction speed was insignificant. Interestingly, the preoperative and intraoperative reaction times are significantly longer in the A-A-A cohort, namely PreOP: A-A-A (1343 ±918 ms ) vs. S-A-A (609 ± 326 ms), IntraOP: A-A-A (1112 ± 374ms) vs. S-A-A (815 ± 260 ms).

Conclusion: Patients in the S-A-A cohort react 34% slower during surgery than the day before surgery. The intraoperative reaction times were not significantly longer than preoperative in A-A-A cohort. Furthermore, the reaction time in S-A-A cohort was significantly longer during the first 10 and >60 intraoperative minutes than preoperatively. Hence, according to our data the optimal time window for cortical mapping in Sleep-Awake-Awake craniotomy possibly starts 10 minutes and ends 60 minutes after extubation of the patient.

Figure 1 [Fig. 1]