Application of depth of anesthesia monitoring in predicting postoperative cognitive impairment in elderly cancer patients / 肿瘤研究与临床

Objective:To investigate the role of depth of anesthesia monitoring in predicting postoperative cognitive impairment in elderly cancer patients.Methods:The clinical data of 70 elderly cancer patients in Shanxi Province Cancer Hospital from February 2020 to February 2021 were retrospectively analyzed. According to the postoperative cognitive function, they were divided into the postoperative cognitive impairment group (20 cases) and the normal postoperative cognitive function group (50 cases). Statistical analyses of the mini mental state examination (MMSE) score of cognitive function, mean arterial pressure (MAP) and bispectral index score (BIS) before anesthesia (T 0), before skin incision (T 1), 1 h after skin incision (T 2), 2 h after skin incision (T 3), at the completion of surgery (T 4), and at the time point of extubation (T 5), as well as the levels of interleukin-6 (IL-6) and central nervous specific protein (S100-β) at 1 d before operation, immediately after surgery and 1 d after surgery between the two groups were performed. Results:The MMSE score of patients in the postoperative cognitive impairment group was lower than that in the normal postoperative cognitive function group [(21±3) points compared with (25±5) points], and the difference between the two groups was statistically significant ( t = 2.98, P < 0.05). The MAP of the two groups at T 1, T 2, T 3, T 4, and T 5 gradually increased (both P < 0.05), the MAP at T 1, T 2, T 3, T 4 was lower than that at T 0 (all P < 0.05), and the MAP at T 5 was higher than that at T 0 (both P < 0.05). There were no statistical differences in MAP between the two groups at T 0, T 1, T 2, T 3, T 4, and T 5 (all P > 0.05). BIS values of the two groups at T 0, T 1, T 2, and T 3 gradually decreased (both P < 0.05), BIS values at T 4 and T 5 gradually increased (both P < 0.05). At T 2 and T 3, BIS value of the postoperative cognitive impairment group was lower than that of the normal postoperative cognitive function group (both P < 0.05). The duration of BIS < 45 in the postoperative cognitive impairment group was longer than that in the normal postoperative cognitive function group [(44.1±7.7) min than (12.6±2.2) min], and the difference between the two groups was statistically significant ( t = 26.68, P < 0.001). The levels of IL-6 and S100-β in the two groups were gradually increased 1 d before surgery, immediately after surgery and 1 d after surgery (both P < 0.05). On the 1st day after surgery, the S100-β level in the postoperative cognitive impairment group was higher than that in the normal postoperative cognitive function group ( P < 0.05). Conclusions:The application of depth of anesthesia monitoring is of high value in predicting postoperative cognitive impairment in elderly cancer patients.

Changes in bispectral index score and cardiorespiratory function under constant rate infusion with alfaxalone in dogs

Changes in the cardiovascular and bispectral index score were evaluated in dogs subjected to constant rate infusion (CRI) with alfaxalone. Fifteen dogs were assigned to three groups of 5. Groups and doses of alfaxalone were as follows: group 1, 3 mg/kg for induction and 6 mg/kg/h for CRI; group 2, 3 mg/kg for induction and 8 mg/kg/h for CRI; and group 3, 3 mg/kg for induction and 10 mg/kg/h for CRI. CRI was maintained for 1 h. Respiratory rates and blood pressures showed minimal changes; however, mild tachycardia and mild hypoxemia occurred, especially in group 3. There were some disparities between bispectral index score, electromyography and pedal withdrawal reflex test when measuring anesthetic depth. Additional premedications and/or analgesic agents would be helpful to avoid adverse effects of alfaxalone and provide improved cardiopulmonary functions.

A Study of the Usefulness of the Bispectral Index Monitor During Pediatric Procedural Sedation by Rectal Thiopental Administration in the Emergency Department

PURPOSE: Recently, the bispectral index monitor has been promoted as an objective measure of sedation depth during pediatric procedural sedation in the emergency department (ED). However, rectal administration of thiopental sodium for pediatric procedural sedation has not been validated. METHODS: Patients aged one to seven years and undergoing primary closure procedures for simple facial and hand laceration in the ED were enrolled. Procedural sedation was performed by rectal administration of thiopental sodium. The bispectral index score and the Ramsay Sedation Scale were recorded every 10 minutes during sedation. The investigator and treating physician were blinded to bispectral index scores, which were later correlated with the Ramsay Sedation Scales values. Receiver operator characteristic (ROC) curves were conducted to determine the ability of the bispectral index score to discriminate various thresholds of sedation depth. RESULTS: One hundred thirty paired measurements were obtained from 12 patients. The Spearman's correlation coefficient for paired measurements, was -0.906 (95% confidence interval: [-9.8] ~ [-8.1], p<0.001). ROC curve analysis demonstrated a high discriminatory power for bi-spectral index scores in predicting the level of sedation, with areas under the curve at least 0.95 for all Ramsay Sedation Scale thresholds. CONCLUSION: Bispectral index monitoring can serve as a useful, objective measure of sedation depth in pediatric procedural sedation with rectal administration of thiopental sodium in the ED.

The Influence of Unilateral Spinal Anesthesia and Conventional Spinal Anesthesia on Sensitivity to Midazolam Sedation / 대한마취과학회지

BACKGROUND: Spinal anesthesia potentiates sedative drug effects. We speculated that an acute decrease in tonic afferent input by spinal anesthesia would decrease the level of consciousness and thereby increase susceptibility to sedative drugs. The experiments were approached with the assumption that the amount of sedative would reduce in the following order: first, the group without spinal anesthesia, second, the group with unilateral spinal anesthesia, and third, the group with conventional spinal anesthesia. METHODS: Patients in group 1 (n = 20) were given midazolam without spinal anesthesia and patients in group 2 (n = 20) received unilateral spinal anesthesia. Those patients who after 20 minutes had a sensory level of T9-11 and a motor block of 3 in dependent side, no sensory block, and a motor block of 0 in the non-dependent side were included. In group 3 (n = 20), patients received conventional spinal anesthesia, and those patients who after 20 minutes had a sensory level of T9-11 and a motor block of 3 were included. The amount of midazolam administered at 33microgram/kg/min to a Bispectral Index score (BIS) of 80 was measured. RESULTS: The dose of midazolam administered to a BIS of 80 was significantly lower in group 3 than in group 1 or group 2. CONCLUSIONS: The sensitivity of sedatives was in the following order: the group with conventional spinal anesthesia, the group with unilateral spinal anesthesia, and the group not administered spinal anesthesia.