Comparative study of orthopaedic robot-assisted minimally invasive surgery and open surgery for limb osteoid osteoma / 中国修复重建外科杂志

OBJECTIVE@#To compare the accuracy and effectiveness of orthopaedic robot-assisted minimally invasive surgery versus open surgery for limb osteoid osteoma.@*METHODS@#A clinical data of 36 patients with limb osteoid osteomas admitted between June 2016 and June 2023 was retrospectively analyzed. Among them, 16 patients underwent orthopaedic robot-assisted minimally invasive surgery (robot-assisted surgery group), and 20 patients underwent tumor resection after lotcated by C-arm X-ray fluoroscopy (open surgery group). There was no significant difference between the two groups in the gender, age, lesion site, tumor nidus diameter, and preoperative pain visual analogue scale (VAS) scores ( P>0.05). The operation time, lesion resection time, intraoperative blood loss, intraoperative fluoroscopy frequency, lesion resection accuracy, and postoperative analgesic use frequency were recorded and compared between the two groups. The VAS scores for pain severity were compared preoperatively and at 3 days and 3 months postoperatively.@*RESULTS@#Compared with the open surgery group, the robot-assisted surgery group had a longer operation time, less intraoperative blood loss, less fluoroscopy frequency, less postoperative analgesic use frequency, and higher lesion resection accuracy ( P<0.05). There was no significant difference in lesion resection time ( P>0.05). All patients were followed up after surgery, with a follow-up period of 3-24 months (median, 12 months) in the two groups. No postoperative complication such as wound infection or fracture occurred in either group during follow-up. No tumor recurrence was observed during follow-up. The VAS scores significantly improved in both groups at 3 days and 3 months after surgery when compared with preoperative value ( P<0.05). The VAS score at 3 days after surgery was significantly lower in robot-assisted surgery group than that in open surgery group ( P<0.05). However, there was no significant difference in VAS scores at 3 months between the two groups ( P>0.05).@*CONCLUSION@#Compared with open surgery, robot-assisted resection of limb osteoid osteomas has longer operation time, but the accuracy of lesion resection improve, intraoperative blood loss reduce, and early postoperative pain is lighter. It has the advantages of precision and minimally invasive surgery.

Effectiveness of robot-guided percutaneous fixation and decompression via small incision for advanced thoracolumbar metastases / 中国修复重建外科杂志

OBJECTIVE@#To evaluate the effectiveness of robot-guided percutaneous fixation and decompression via small incision in treatment of advanced thoracolumbar metastases.@*METHODS@#A clinical data of 57 patients with advanced thoracolumbar metastases admitted between June 2017 and January 2021 and met the selection criteria was retrospectively analyzed. Among them, 26 cases were treated with robot-guided percutaneous fixation and decompression via small incision (robot-guided group) and 31 cases with traditional open surgery (traditional group). There was no significant difference in gender, age, body mass index, lesion segment, primary tumor site, and preoperative Tokuhashi score, Tomita score, Spinal Instability Neoplastic Score (SINS), visual analogue scale (VAS) score, Oswestry disability index (ODI), Karnofsky score, and Frankel grading between groups ( P>0.05). The operation time, hospital stays, hospital expenses, intraoperative blood loss, postoperative drainage volume, duration of intensive care unit (ICU) stay, blood transfusion, complications, and survival time were compared. The pedicle screw placement accuracy was evaluated according to the Gertzbein-Robbins grading by CT within 4 days after operation. The pain, function, and quality of life were evaluated by VAS score, ODI, Karnofsky score, and Frankel grading.@*RESULTS@#During operation, 257 and 316 screws were implanted in the robot-guided group and the traditional group, respectively; and there was no significant difference in pedicle screw placement accuracy between groups ( P>0.05). Compared with the traditional group, the operation time, hospital stays, duration of ICU stay were significantly shorter, and intraoperative blood loss and postoperative drainage volume were significantly lesser in the robot-guided group ( P<0.05). There was no significant difference in hospital expenses, blood transfusion rate, and complications between groups ( P>0.05). All patients were followed up 8-32 months (mean, 14 months). There was no significant difference in VAS scores between groups at 7 days after operation ( P>0.05), but the robot-guided group was superior to the traditional group at 1 and 3 months after operation ( P<0.05). The postoperative ODI change was significantly better in the robot-guided group than in the traditional group ( P<0.05), and there was no significant difference in the postoperative Karnofsky score change and Frankel grading change when compared to the traditional group ( P>0.05). Median overall survival time was 13 months [95% CI (10.858, 15.142) months] in the robot-guided group and 15 months [95% CI (13.349, 16.651) months] in the traditional group, with no significant difference between groups ( χ 2=0.561, P=0.454) .@*CONCLUSION@#Compared with traditional open surgery, the robot-guided percutaneous fixation and decompression via small incision can reduce operation time, hospital stays, intraoperative blood loss, blood transfusion, and complications in treatment of advanced thoracolumbar metastases.

Efficacy of regional cerebral oxygen saturation combined with neuroelectrophysiological monitoring in guiding intraoperative blood pressure management in elderly patients undergoing carotid endar-terectomy / 中华麻醉学杂志

Objective To evaluate the efficacy of regional cerebral oxygen saturation(rSO2) combined with neuroelectrophysiological monitoring in guiding intraoperative blood pressure management in elderly patients undergoing carotid endarterectomy. Methods Thirty patients of both sexes, aged 65-80 yr, of American Society of Anesthesiologists physical statusⅡorⅢ, scheduled for elective carotid endar-terectomy, were divided into 2 groups(n=15 each)using a random number table: control group(group C)and rSO2combined with neuroelectrophysiological monitoring group(group M). During occlusion of carotid artery, the vasoactive drugs were used to make systolic blood pressure(SBP)increase by 20%-30% of the baseline value in group C and to make rSO2not less than 20% of the baseline value, the ampli-tude of somatosensory evoked potential P40 not less than 50% of the baseline value and the amplitude of e-lectroencephalogram voltage not less than 50% in group M. SBP and rSO2were recorded immediately after intubation(T1), at 5 min after anesthesia induction(T2), at 5 min after blocking the carotid artery (T3), at 5 min after opening the carotid artery(T4)and immediately after extubation(T5). Decrease in rSO2≥20% of the baseline value was recorded. The carotid artery occlusion time, myocardial oxygen con-sumption and consumption of vasoactive drugs during occlusion were recorded. Results Compared with group C, SBP was significantly decreased at T3, and the consumption of vasoactive drugs and myocardial oxygen consumption were reduced in group M(P<0.05), and no significant change was found in rSO2at each time point in group M(P>0.05). Decrease in rSO2≥20% of the baseline value was not found in two groups. Conclusion rSO2combined with neuroelectrophysiological monitoring provides guidance for intra-operative blood pressure management in patients undergoing carotid endarterectomy.

Agreement between regional cerebral oxygen saturation and jugular bulb venous oxygen saturation during one-lung ventilation in elderly patients / 中华麻醉学杂志

Objective To evaluate the agreement between regional cerebral oxygen saturation (rSO2) and jugular bulb venous oxygen saturation (SjvO2) during one-lung ventilation (OLV) in elderly patients.Methods Twenty-two patients of both sexes,aged 65-76 yr,with body mass index of 21-32 kg/m2,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ,undergoing open pulmonary lobectomy or radical resection of esophageal cancer with combined intravenous-inhalational anesthesia,were selected.Immediately after beginning of two-lung ventilation (T0),at stable two-lung ventilation in the lateral position (T1),at 5,25 and 45 min of OLV in the lateral position (T2-4) and at the end of OLV in the lateral position (T5),blood samples were collected from the jugular bulb for blood gas analysis,and SjvO2 was recorded,rSO2 was also recorded at the time points mentioned above.Bland-Altman analysis was used to evaluate the agreement.Results SjvO2 was significantly lower at T0-5 than rSO2 (P＜0.05).rSO2 and SjvO2 were gradually decreased at T1-5 (P＜0.05).The results of Bland-Altman analysis showed that the difference between rSO2 more than 95％ and SjvO2 was within the range of 95％ limits of agreement,and the absolute value of the maximum difference was 20.8％.Conclusion There is a good agreement between rSO2 and SjvO2 during OLV in elderly patients,and SjvO2 can be recommended as an alternative to rSO2 clinically.

Clinical value of water exchange colonoscopy / 中华消化内镜杂志

Objective To compare sedated water exchange and conventional colonoscopy in the recovery time,rates of reaching ileocecal valve and adenoma detection.Methods A total of 200 newly diagnosed patients undergoing colonoscopy with routine bowel preparation and propofol intravenous anesthesia were randomly divided into 2 groups:water exchange group (WE) and conventional group,100 patients in each group.The operations were performed by two experienced physicians.The recovery time,rates of reaching ileocecal valve and adenoma detection of each group were analyzed and compared after operation.Results The recovery times of patients in water exchange and conventional groups were 8.08±0.58 min and 12.34±0.72 min,respectively (F =2 147.33,P＜ 0.05).Rates of reaching ileocecal valve were 100.00％(100/100,WE group) and 96.00％ (96/100,conventional group),respectively(x2 =4.17,P＜0.05).Adenoma detection rates of whole colon were 43.00％ (43/100,WE group) and 29.00％ (29/100,conventional group) (x2=4.25,P＜0.05),of which small adenomas (＜ 1.0 cm) accounted for 83.96％ (89/106,WE group) and 70.59％ (48/68,conventional group) (x2 =4.43,P ＜ 0.05),respectively.Adenoma detection rates of proximal colon were 28.00％ (28/100,WE group) and 20.00％ (20/100,conventional group) (x2 =1.75,P＞ 0.05),of which small adenomas (＜ 1.0 cm) accounted for 90.41％ (66/73,WE group) and 74.47％ (35/47,conventional group) (x2 =5.45,P ＜ 0.05),respectively.Conclusion Water exchange colonoscopy can not only shorten the recovery time of patients,but also increase rates of reaching ileocecal valve and adenoma detection.

Synergistic antitumor effects via apoptosis of quercetin in combination with cisplatin in the prostate cancer cells / 中华泌尿外科杂志

Objective To study the synergistic antitumor effects of quercetin and cisplatin in human prostate cancer PC3 cells and LNCaP cells.Methods Twelve h after PC3 cells or LNCaP cells were seeded,different dose of quercetin (10 μmol/L,20 μmol/L,40 μmol/L,80 μmol/L,160 μmol/L) or cisplatin (0.01 μmol/L,0.05 μmol/L,0.1 μmol/L,1 μmol/L,10 μmol/L),or quercetin (20 μmol/L) + cisplatin (0.01 μmol/L,0.05 μmol/L,0.1 μmol/L,1 μmol/L,10 μmol/L) were added for48 h and then the antiproliferative effects were detected with MTT assay.After incubated with quercetin (20 μmol/L) or cisplatin (0.05 μ mol/L),or quercetin (20 μ mol/L) + cisplatin (0.05 μmol/L) for48 h,cell cycle distribution and apoptosis of PC3 cells or LNCaP cells were detected by flow cytometer,PI and Annexin V staining.Protein expression was detected by Western blotting.Results After treatment with quercetin or cisplatin alone,the IC50 were (0.99 ± 0.13) μmol/L,(0.75 ± 0.09) μmol/L and (91.60 ± 6.10) μ mol/L,(72.90±4.70) μ mol/L for LNCaP cells or PC3 cells,respectively;The IC50 were (0.11±0.06)μ mol/L,(0.07±0.02) μmol/L for quercetin + cisplatin treatment (Compared with quercetin,P＜0.01 ;Compared with cisplatin,P＜0.05.After treatment with cisplatin or quercetin + cisplatin for 48 h,the S phase percent of LNCaP cells or PC3 cells were (22.4±2.7)％,(31.2±2.4)％ and (20.1±1.6)％,(31.0±2.5)％,respectively,(Compared with control,P＜0.05,however,treatment with quercetin alone has no significant difference (Compared with control,P＞0.05).After treatment with cisplatin or quercetin + cisplatin for 48 h,the apoptotic percent of LNCaP cells or PC3 cells were (14.8 ± 1.9) ％,(39.6 ± 3.1) ％ and (11.5± 1.2) ％,(34.1 ±3.3) ％,respectively,(compared with control,P ＜ 0.05,however,treatment with quercetin alone had no significant difference (compared with control,P＞0.05).After treatment with quercetin alone for 48 h,the activation of caspase-3,caspase-8 and caspase-9 were slightly increased,the expressions of Bax and p21 were up-regulated,the expressions of Bcl-2 and CDK2 were down-regulated.Furthermore,these effect of cisplatin and quercetin + cisplatin were significantly enhanced (compared with quercetin,P＜0.05;compared with quercetin,P＜0.01,respectively.Conclusions The combination modality with quercetin and cisplatin has a better treatment effect in vitro not only in androgen-dependent LNCaP cells but also in androgen-independent PC3 cells.

Effects of sevoflurane on transcranial electrical motor evoked potential monitoring elicted from four-limb muscles / 复旦学报（医学版）

Objective To compare the influence of different end-tidal concentrations of sevoflurane on transcranial electrical four-limb muscle motor evoked potential (MEP) monitoring. Methods Twenty ASA Ⅰ-Ⅱpatients aged 23-62 years undergoing craniotomy were enrolled. Triangular muscle, biceps brachii muscle, triceps brachii muscle, brachioradialis muscle, extensor digitorum communis muscle, abductor pollicis brevis abductor digiti minimi muscle, rectus femoris muscle, tibialis anterior muscle, gastrocnemius muscle and abductor hallucis were selected for MEPs recording. Sevoflurane was introduced at 0.5, 0.75, 1.0 and then 1.3 MAC (15 min each), and the effects on MEPs were studied. Results ①Maximum MEP amplitude was observed at abductor pollicis brevis muscle in upper limb and abductor hallucis muscle in lower limb at baseline and 0.5 MAC. Up to 1.0 MAC, there was no significant difference in MEP amplitude among extensor digitorum communis muscle, abductor pollicis brevis and abductor digiti minimi muscle. ②The success rate of MEP recording from abductor pollicis brevis muscle and abductor hallucis muscle was 100% during the administration of 0.5-1.0 MAC sevoflurane. ③The MEP amplitude was decreased and the latency was increased in a sevoflurane dose-dependent manner. Conclusions Abductor pollicis brevis muscle and abductor hallucis muscle were suitable for MEP monitoring during the administration of 0.5-1.0 MAC sevoflurane.

Pharmacodynamics of different local anesthetics administered intrathecally for caesarean section / 中华麻醉学杂志

Objective To investigate tbe pharmacodynamics of different local anesthetics administered intrathecally for caesarean section. Methods Ninety-six parturients with singleton term pregnancies undergoing caesarean section under combined spinal-epidural anesthesia were enrolled in this study. The patients were randomly divided into 3 groups ( n = 32 each ) and received intrathecal (IT) 0.5 % bupivacaine, 0.5 %levobupivacaine and 0.5% ropivacaine respectively. The initial doses was 9 mg in all 3 groups. The ratio of two successive doses was 0.9. If the upper sensory block reached T7 or above and there was no need for additional dose in the 45 min after the initial dose, the IT analgesia was considered to be effective. The median effective dose ( ED50 ), the 95 % effective dose( ED95) and 95 % confidence interval (95 % CI )were calculated by Dixon. Results The ED50 and ED95 and 95%CI of bupivacaine were 6.15 (95%CI 5.48-6.68) mg and 7.62 (95%CI 6.91-11.82) mg; of levobupivacaine were 8.06 (95%CI 7.46-8.62) mg and 9.59 (95%CI 8.86-13.42) mg;of ropivacaine were 10.55 (95%CI 9.73-11.49) mg and 12.80 (95%CI 11.66-21.42) mg. The relative potency potency ratio between bupivacaine, levobupivacaine and rupivacaine is 1.00:0.76:0.58.

Effects of tetanic stimulation of peripheral nerve on intracranial direct electrical stimulation motor-evoked potentials in patients undergoing cerebral functional area operation / 中华麻醉学杂志

Objective To investigate the effects of tetanic stimulation of peripheral nerve on intracranial direct electrical stimulation motor-evoked potentials (MEP) in patients undergoing cerebral functional area operation. Methods Eight patients undergoing elective brain tumor resection under propofol-fentanyl anesthesia with partial neuromuscular blockade were enrolled in the study. Both conventional MEP (C-MEP) monitoring and posttetanic MEP (P-MEP) monitoring were performed throughout the operation for each patient, and the two groups of data were recorded. For one group, direct electrical stimulation with a train of five pulses was delivered to motor cortex and pyramidal tract, C-MEP was unilaterally recorded from the abductor pollicis brevis, and P-MEP was obtained 1 s after tetanic stimulation (frequency 50 Hz, intensity 50 mA, duration 5 s) to the ipsilateral tibial nerve.For the other group, direct electrical stimulation with a train of five pulses was delivered to motor cortex and pyramidal tract, C-MEP was unilaterally recorded from the tibialis anterior, and P-MEP was obtained 1 s after tetanic stimulation (frequency 50 Hz, intensity 50 mA and duration 5 s) to the contralateral tibial nerve. Randomized crossover method was used for C-MEP and P-MEP recording in each group, with an interval of 120 s. The adverse effects were observed. Results Amplitudes of P-MEP from the abductor pollicis brevis and tibialis anterior were significantly higher than those of C-MEP. Three patients had body movement during intraoperative cortex stimulation, while there was no awareness during operation and other electrical stimulation-related nervous system impairment and complications. Conclusion The application of tetanic stimulation of peripheral nerve before direct electrical stimulation can augnent the amplitudes of MEP from the abductor pollicis brevis and tibialis anterior in patients undergoing cerebral functional area operation.

Effects of sevoflurane,isoflurane and desflurane on transcranial electrical motor evoked potentials in patients undergoing neurosurgery / 中华麻醉学杂志

Objective To compare the effects of sevoflurane,isoflurane and desflurane on transcranial electrical motor evoked potentials(MEPs)in patients undergoing neurosurgery.Methods Sixty ASA Ⅰ or Ⅱ patients aged 18-64 yr undergoing neurosurgery were randomly divided into 3 groups(n = 20 each): sevoflurane group,isoflurane group and desflurane group.BIS value and MEPs were monitored.The end-tidal concentrations of sevoflurane,isoflurane and desflurane were adjusted and maintained at 0.50,0.75,1.00 and 1.30 MAC respectively for at least 15 min during 6 stimuli delivered at 1000 Hz and 300 V lasting for 75 μs.The amplitudes and latency of MEPs and BIS value were recorded before administration(baseline)and the each stable state (T1-4).The failure rate of MEPs was also recorded.Results The amplitude of MEPs and BIS value were significantly decreased at T1.2 and the latency of MEPs was prolonged at T1-4 in desflurane group compared with sevoflurane and isoflurane groups(P＜0.05).There was no significant difference in the amplitudes and latency of MEPs and BIS value between group sevoflurane and isoflurane(P＞0.05).The failure rates of MEPs were 0 at baseline,T1 and T2,0,5% and 20% at T3 ,and 5%,20% and 45% at T4 in sevoflurane,isoflurane and desflurane groups respectively.The failure rate of MEPs was significantly higher in desflurane group than in sevoflurane and isoflurane groups(P＜0.05).Conclusion Desflurane has greater suppressive effect on MEPs than sevoflurane and isoflurane.1.00 MAC of sevoflurane and isoflurane,while 0.75-1.00 MAC of desflurane may be the suitable end-tidal concentration for MEP monitoring.

Changes of cerebral blood flow and cerebral autoregulation during propofol or sevoflurane anaesthesia in patients undergoing gynecologic laparoscopic surgery / 复旦学报（医学版）

Objective To observe the effects of propofol or sevoflurane combined with remifentanil on cerebral blood flow (CBF) and cerebral autoregulation in patients undergoing gynecologic laparoscopic surgery. Methods Forty patients were randomly divided into two groups: the propofol group (group P, n=20) and the sevoflurane group (group S, n=20). Anaesthesia was induced with target-controlled infusion (TCI) of propofol and remifentanil in group P, with an inhaled induction of sevoflurane and TCI of remifentanil in group S, respectively. The depth of anesthesia was regulated according to bispectral index (BIS). The pressure of end-tidal carbon dioxide (P_(ET)CO_2) was kept at 35-40 mmHg by mechanical ventilation. The mean arterial pressure (MAP), heart rate (HR), pressure of arterial carbon dioxide (PaCO_2), P_(ET)CO_2, time-averaged peak flow velocity (TAP) and the transient hyperaemic response ratio (THRR) were recorded at 7 different time points: supine position (T_1) and supine lithotomy position before induction (T_2), the instant and 5 min after tracheal intubation (T_3,T_4), the instant and 15 min after abdominal CO_2 insufflation and trendelenburg-lithotomy position (T_5,T_6), and 10 min after the deflation abdomen (T_7), respectively. Results Compared with the baseline values at T_1, TAP was not significantly changed at T_2, T_5, or T_6 in group P, but was markedly decreased at T_3, T_4 and T_7. TAP in group S only decreased at T_4 and T_7, while it was much higher than that in group P at T_3. In group S, THRR was markedly lowered at T_3 compared with that at T_1; but in group P, it showed a significant increase at T_3. Conclusions Combined with remifentanil, propofol decreased CBF, but has no effect on the brain self-regulation. When inhaled in high concentrations, sevoflurane significantly reduces the brain self-regulation. Intraoperation pneumoperitoneum and postural factor significantly increase CBF, playing a stronger role than the narcotic drugs in clinical dosage (propofol, sevoflurane), without any influence on the brain self-regulation.

The effect of magnetic field on serum free radicles in patients undergoing operation for pituitary tumor / 复旦学报（医学版）

Objective To study the effect of magnetic field on serum activity of superoxide dismutase (SOD), content of malon-dialdehyde (MDA)and content of nitric oxide (NO)in patients undergoing operation for pituitary Tumor. Methods Sixteen ASA Ⅰor Ⅱ patients undergoing pituitary tumor surgery under general anesthesia were randomly divided into 2 groups (n=8 each): magnetic field group (M) and control group (C). Patients in magnetic field group were exposed in 150 mT magnetic field during the operation period.Blood samples were taken from radial artery for determination of serum SOD,MAD and NO before induction of anesthesia(T_0, baseline),after induction(T_1),70 min after induction(exposed in magnetic field for 60 min) (T_2)and 130 min after induction (exposed in magnetic field for 120 min) (T_3). Results There was no significant difference between the two groups in age, sex (M/F ratio),body weight,body height,duration of operation and duration of anaesthesia.The serum activity of SOD and content of NO were significantly higher at T_3 in group M than that in group C,and the serum content of MDA was lower at T_3 in group M than that in group C. Conclusions The magnetic field not only increases serum SOD activity and the content of NO in patient undergoing operation for pituitary tumor,but also reduces the content of MDA in them.

Treatment of Bleeding Esophageal Varices with Endoscopic Variceal Ligation Plus Somatostatin / 中国药房

OBJECTIVE:To evaluate the short and long-term therapeutic effects of endoscopic variceal ligation(EVL) plus somatostatin on bleeding esophageal varices METHODS:64 patients with acute esophageal variceal bleeding due to portal hypertension underwent EVL,then the patients were divided into EVL group and EVL+somatostatin group RESULTS:The short-term hemostatic rates reached 93% in both groups There were significant differences in postoperative rebleeding rate and average interval of rebleeding between two groups(P

Effects of intra-abdominal pressure and duration of pneumoperitoneum on splanchnic perfusion in patients undergoing laparoscopic cholecystectomy / 中华麻醉学杂志

Objective The present study was designed to compare the effects of different intra-abdominal pressure and the duration of pneumoperitoneum on splanchnic perfusion during laparoscopic cholecystectomy. Methods Fifty ASA Ⅰ or Ⅱ patients aged

Feasibility of intraoperative monitoring of somatosensory evoked potential in neurosurgery around the brain stem / 中华麻醉学杂志

Objective To study the feasibility and reliability of median nerve somatosensory evoked potential monitoring in neurosurgery around the brain stem. Methods in selected 43 patients SEP N20, waveforms were recorded after stimulation of left and right median nerves respectively. Anesthesia was maintained with intravenous anesthetics throughout the operation. As soon as N20 waveform changed significantly, the surgeon was informed and the operative procedure was modified whenever possible. Results SEP waveforms were almost stable during maintaining with total intravenous anesthesia (TIVA). Within 43 cases, SEP waveform of & patients significantly changed. In these cases, SEP of 5 patients returned to normal gradually and no further neurologic dysfunction happened postoperatively. The other 3 cases did not recover, and postoperative neurologic complications happened. There was no false-negative or false-positive result. The correlation between intraoperative SEP changes and postoperative neurologic alterations was significant statistically. Conclusions SEP recording is a reliable technique for intraoperative monitoring during neurosurgery around the brain stem. TIVA is helpful for SEP monitoring.

Effects of volatile anesthetics on short-latency somatosensory evoked potentials / 中华麻醉学杂志

ve In order to improve the reliability of somatosensory evoked potentials (SSEP) monitoring during anesthesia, we compared the effects of three commonly used volatile anesthetics on SSEP to choose suitable volatile anesthetic and determine the appropriate end-expiratory concentrations which have least effects on SSEP monitoring. Methods Sixty ASA I - II patients undergoing elective intracranial surgery were randomly divided into three groups: group A received enflurane; group B isoflurane and group C desflurane. The demographic data including age, body weight, height and sex were not significantly different between the three groups. In addition to SSEP, ECG, BP, SpO2, PET CO2 and end-tidal concentration of inhalation anesthetic were monitored. The SSEP electrodes were placed on N13 on the neck and N20 on the scalp. Before experiment the patient was asked to lie quietly for 10 min, then the patient started breathing 100% O2 and fresh-gas-flow (FGF) was set at 5 L/min. Median nerve on one side was stimulated and SSEP waves from cortex and cervical spinal cord were recorded as baseline tracing before anesthesia. The concentration of inhalation anesthetic was gradually increased from 0 to 0.3, 0.5, 0.75, 1.0 and 1.5 MAC. Each concentration was maintained for 15 min and SSEP waves were recorded. During experiment if the patient developed respiratory depression, oral airway was inserted and assisted ventilation was performed to maintain PETCO2 at 35-45minHg. If the patient developed hypotension, fluid was infused at an increased rate and vasopressor was given if necessary to maintain normal BP (baseline ? 20 % ) . Results The three volatile anesthetics did not change N13 latency and amplitude. Increasing concentrations of enflurane, isoflurane and desflurane were associated with graded reduction in N20 amplitude and increase in N20 latency and N13-N20 interpeak latency. Conclusions The results suggest (1) cortical SSEPs are moresensitive to the volatile anesthetics than subcortical SSEPs, (2) end-tidal concentration of enflurane less than 0.75 MAC is compatible with effective SSEP monitoring, whereas the end-tidal concentration of isoflurane or desflurane compatible with effective SSEP monitoring was less than 1.0 MAC. Enflurane has greater effect on SSEP than isoflurane and desflurane.

Effect of propofol,midazolam and etomidate on short latency somatosensory evoked potential / 中华麻醉学杂志

Objective: To study the effect of three different doses of propofol, midazolam and etomidate on short latency somatosensory evoked potential(SLSEP). Method:Ninety patients undergoing elective operation were randomly divided into 3 groups with 3 subgroups each,and propofol,midazolam,etomidate were administered by bolus injection at propofol 1.5,2,3mg/kg, midazolam 0.2,0.3,0.4mg/kg, etomidate 0.15,0.3,0.4mg/kg accordingly. SLSEP was recorded before,during and after injection. Result:Propofol did not significantly change the latencies of the subcortical N_(14),cortical N_(20) and central conduction time(CCT)N_(14)-N_(20),decreased the interwave amplitude N_(20)-P_(25)(P

Effects of nicardipine-induced hypotension on splanchnic perfusion in patient undergoing meningioma resection / 中华麻醉学杂志

Objective Controlled hypotension induced by different drugs may have different effects on splanchnic perfusion. The purpose of this study was to assess the effects of nicardipine- induced hypotension on splanchnic perfusion. Methods Twenty-three ASA Ⅰ-Ⅱ patients (14 male, 9 female) aged 21-60 yr undergoing meningioma resection were studied. The patients were premedicated with ranitidine 150 mg per os and atropine 0.5 mg i.m. Anesthesia was induced with propofol 1.5-2.0 mg?kg-1 , fentany1 2.0?g?kg-1 and vecuronium 0.1 mg? kg-1 and maintained with isoflurane inhalation and intermittent i. v. boluses of fentanyl and vecuronium. The patients were mechanically ventilated after tracheal intubation and PETCO2 was maintained at 33-35 mm Hg. Nicardipine-induced hypotension started from opening of mininges to the resection of tumor. 0.01% nicardipine infusion was started at 30 ml?h-1 and adjusted to reduce systolic blood pressure by 30% of the baseline or MAP to≥60 mm Hg. The adequacy of splanchnic perfusion was defined by gastric intramucosal CO2 tension (PgCO2), the intramucosal pH (pHi) and the difference between intramucosal and arterial PCO2(PCO2 gap) and was assessed before induction of anesthesia, the 1st, 2nd and 3rd hour during controlled hypotension and 1, 2 hour after termination of controlled hypotension. Results The MAP was maintained at about 62 mm Hg during controlled hypotension. The heart rate was stable. Hct was significantly decreased at 1st, 2nd and 3rd hour of hypotension compared with baseline but the mean Hct was greater than 30% . The intramucosal pH decreased slightly with no statistical significance and pHa, PaCO2 , PgCO2 and PCO2 gap were almost unchanged during controlled hypotension compared with the baseline values. Conclusion Nicardipine-induced hypotension is safe when MAP is maintained at≥60 mm Hg and has no adverse effects on splanchnic perfusion.