Table 1 The characteristics of the included studies
Study ID | Country | Design | Group | Anesthetic type | Surgical procedure | Grade of ASA | Age range (years) | Control | Anesthsia depth momotoring | Strategy of DEX | Cognitive problem | Assessment or define |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dr.Deb Sanjay Nag 2020 [12] | India | 2-arm RCT | DEX60 Control 60 | Spinal Anesthesia | Hip surgery | I-III | 60–75 | NS | NR | Loading dose of DEX 1 mcg/kg over 10 min, after Spinal Anaesthesia and before start of surgery, followed by a continuous infusion ( 0.4 mcg/kg/h) until the end of surgery | POCD | MoCA scores below 26 were considered as POCD |
Tianqiu Zhu 2019 [13] | China | 2-arm RCT | DEX32 Control 32 | combined spinal-epidural anesthesia | Hip surgery | II-III | 72 + | NS | NR | followed by a continuous infusion (0.3 μg/ kg/h) | POCD | NR |
Zhengxuan Guo 2017 [14] | China | 3-arm RCT | DEX30 Control60 | combined spinal-epidural anesthesia | hip replacement | II-III | 65–92 | NS/Midazolam | NR | Loading dose of DEX 0.6 μg/kg in 15 min and followed by a continuous infusion (0.2–0.5 μg/ kg) | POCD | MMSE scores of 24–27 are considered mild POCD, 19–23 are moderate POCD, and 0–18 are severe POCD |
Jie Gao 2018 [15] | China | 2-arm RCT | DEX47 Control47 | combined spinal-epidural anesthesia | Knee Arthroplasty | II-III | 60–77 | NS | NR | Loading dose of DEX 1 μg/kg/h in 10 min and followed by a continuous infusion (0.5 μg/ kg/h) | POCD | A reduction of ≥ 2 points in MMSE score compared with preoperative period can be determined as POCD |
Xinglong Qin 2016 [16] | China | 2-arm RCT | DEX40 Control40 | combined spinal-epidural anesthesia | lower extremity orthopedic surgery | II-III | 65–93 | NS | NR | Loading dose of DEX 0.5 μg/kg/h in 10 min and followed by a continuous infusion (0.4 μg/ kg/h) | POCD | A reduction of ≥ 2 points in MMSE score compared with preoperative period can be determined as POCD |
Xiue Zhao 2018 [17] | China | 2-arm RCT | DEX30 Control30 | combined spinal-epidural anesthesia | lower extremity orthopedic surgery | I-III | 65 + | NS | NR | Loading dose of DEX 1 μg/kg/h in 15 min and followed by a continuous infusion (0.2–0.7 μg/ kg/h) | POCD | MMSE scores ≤ 23 were considered as POCD |
Yu Qi 2020 [18] | China | 2-arm RCT | DEX100 Control100 | epidural anaesthesia | lower extremity orthopedic surgery | I-II | 65 + | NS | BIS | Loading dose of DEX 0.5 μg/kg/h in 10 min and followed by a continuous infusion (0.2 μg/ kg/h) | POCD | MMSE scores ≤ 23 were considered as POCD |
Jiong Shi 2021 [19] | China | 2-arm RCT | DEX66 Control66 | combined spinal-epidural anesthesia | NR | I ~ III | 60 + | NS | Ramsay | Loading dose of DEX 0.5 μg/kg/h in 15 min | POCD | the patient's postoperative reversible and fluctuating acute mental confusion syndrome is defined as POCD, which includes inattention, incoherent thinking, and decreased social activity ability |
Xiaowei Zhang 2020 [20] | China | 2-arm RCT | DEX59Control59 | Spinal Anesthesia | Knee Arthroplasty | I-II | 60–82 | blank | NR | Loading dose of DEX 0.5 μg/kg/h in 10 min and followed by a continuous infusion (0.2 μg/ kg/h) | POD | NR |
Bin Mei 2018 [21] | China | 2-arm RCT | DEX148 Control 148 | nerve block | Hip Arthroplasty | I–IV | 65 + | propofol | BIS | Loading dose of DEX0.8–1 μg/kg in 15–20 min, after Spinal Anaesthesia and followed by a continuous infusion (0.1–0.5 μg/ kg/h) | POD | CAM |
Bin Mei 2020 [22] | China | 2-arm RCT | DEX183 Control 183 | Spinal Anesthesia | Knee Arthroplasty | I-IV | 65 + | propofol | BIS | Loading dose of DEX0.8–1 μg/kg in 15–20 min and followed by a continuous infusion (0.1–0.5 μg/ kg/h) | POD | CAM |
Shin 2023 [23] | Korea | 2-arm RCT | DEX366 Control 366 | Spinal Anesthesia | lower extremity orthopedic surgery | I-II | 65 years or older | Propofol | OAA/S | Loading dose of DEX1 μg/kg in 10 min and followed by a continuous infusion (0.1–0.5 μg/ kg/h) | POD | CAM |
Feng Zhou 2022 [24] | China | 4-arm RCT | DEX21 Control 63 | combined spinal-epidural anesthesia | Hip surgery | I-III | 65 years or older | Esketamine/NS/Esketamine + dexmedetomidine | NR | Loading dose of DEX0.6 μg/kg in 10 min and followed by a continuous infusion (0.3 μg/ kg/h) | POD | CAM |
Xuan Wang 2020 [25] | China | 2-arm RCT | DEX57 Control 57 | combined spinal-epidural anesthesia | Hip surgery | I–IV | 65 + | NS | NR | Loading dose of DEX0.5 μg/kg in 10 min and followed by a continuous infusion (0.4 μg/ kg/h) | POD | CAM |
Yali Ge 2021 [26] | China | 2-arm RCT | DEX52 Control52 | combined spinal-epidural anesthesia | hip replacement | I ~ II | 60–80 | NS | NR | Loading dose of DEX 0.5 μg/kg in 15 min and followed by a continuous infusion (0.4 μg/ kg/h) | POD | CAM |
Wenqing Xu 2020 [25] | China | 2-arm RCT | DEX40 Control40 | Spinal Anesthesia | Hip surgery | II-III | 80–95 | NS | NR | followed by a continuous infusion (0.2 μg/ kg/h) | POD | CAM |
Haijun Weng 2022 [27] | China | 2-arm RCT | DEX41 Control41 | combined spinal-epidural anesthesia | orthopedic surgery | I ~ II | 65 + | NS | NR | Loading dose of DEX0.4 μg/kg/h in 15 min and followed by a continuous infusion (0.2 μg/ kg/h) | POD | NR |