Objective To investigate the predictive value of the mini-fluid challenge test in elderly orthope-dic patients for post-spinal anesthesia hypotension.Methods Seventy-two elderly patients who underwent elective hip or knee replacement surgery were rigorously screened according to predefined inclusion and exclusion criteria.All patients were scheduled for subarachnoid block anesthesia.Subjects were grouped based on changes in blood pressure within 15 minutes of assuming a supine position following single-shot lumbar anesthesia.According to previ-ously established definitions of hypotension,they were categorized into either the hypotension group(H group)or the normal blood pressure group(N group).Prior to spinal anesthesia,a mini-fluid challenge test was conducted using noninvasive cardiac output monitoring to measure the change in stroke volume index(ΔSVI),and baseline circulatory data were recorded.Multivariate logistic regression analysis was employed to identify factors influencing outcomes in elderly patients undergoing orthopedic joint replacement surgery.Receiver operating characteristic(ROC)curves for ΔSVI were constructed,and the area under the curve(AUC)was calculated to evaluate its predic-tive performance.Results After spinal anesthesia,29 patients(40.27%)experienced hypotension.Compared with Group N,patients in Group H who experienced hypotension within 15 minutes while in a supine position were signifi-cantly older,had a higher proportion of ASA grade III,and a higher prevalence of hypertension(P<0.05).The analysis results indicated that ΔSVI was an independent influencing factor for post-lumbar anesthesia hypotension in elderly patients.ΔSVI demonstrated a sensitivity of 82.8%and a specificity of 81.4%in predicting post-spinal anes-thesia hypotension(PSAH)at a cut-off value of 0.805 or greater.There was a moderate positive linear correlation between the maximum decrease in systolic blood pressure(SBP)and ΔSVI(r=0.562,P<0.01).Conclusion The mini-fluid challenge test is an effective method for predicting hypotension in elderly orthopedic patients following spinal anesthesia.

Objective To investigate the predictive value of the mini-fluid challenge test in elderly orthope-dic patients for post-spinal anesthesia hypotension.Methods Seventy-two elderly patients who underwent elective hip or knee replacement surgery were rigorously screened according to predefined inclusion and exclusion criteria.All patients were scheduled for subarachnoid block anesthesia.Subjects were grouped based on changes in blood pressure within 15 minutes of assuming a supine position following single-shot lumbar anesthesia.According to previ-ously established definitions of hypotension,they were categorized into either the hypotension group(H group)or the normal blood pressure group(N group).Prior to spinal anesthesia,a mini-fluid challenge test was conducted using noninvasive cardiac output monitoring to measure the change in stroke volume index(ΔSVI),and baseline circulatory data were recorded.Multivariate logistic regression analysis was employed to identify factors influencing outcomes in elderly patients undergoing orthopedic joint replacement surgery.Receiver operating characteristic(ROC)curves for ΔSVI were constructed,and the area under the curve(AUC)was calculated to evaluate its predic-tive performance.Results After spinal anesthesia,29 patients(40.27%)experienced hypotension.Compared with Group N,patients in Group H who experienced hypotension within 15 minutes while in a supine position were signifi-cantly older,had a higher proportion of ASA grade III,and a higher prevalence of hypertension(P<0.05).The analysis results indicated that ΔSVI was an independent influencing factor for post-lumbar anesthesia hypotension in elderly patients.ΔSVI demonstrated a sensitivity of 82.8%and a specificity of 81.4%in predicting post-spinal anes-thesia hypotension(PSAH)at a cut-off value of 0.805 or greater.There was a moderate positive linear correlation between the maximum decrease in systolic blood pressure(SBP)and ΔSVI(r=0.562,P<0.01).Conclusion The mini-fluid challenge test is an effective method for predicting hypotension in elderly orthopedic patients following spinal anesthesia.

Objective:To evaluate the effect of individualized positive end-expiratory pressure (PEEP) ventilation strategy guided by driving pressure on intraoperative intracranial pressure in patients with moderate traumatic brain injury (TBI).Methods:Total of 111 patients aged 18-65 years old, with BMI of 17-28 kg/m 2, ASA grade of Ⅲ-Ⅳ, and Glasgow coma score of 9-11 before operation were treated with evacuation of intracranial hematoma in emergency. The patients were randomly divided into 0 cmH 2O PEEP group (Group 0 PEEP), 5 cmH 2O PEEP group (Group 5 PEEP) and individualized PEEP ventilation group (Group P) guided by driving pressure. The volume control ventilation mode is adopted, VT is 6 mL/kg, FiO 2 is 60%, and the inspiratory expiratory ratio is 1:2. Patients in Group 0 PEEP and Group 5 PEEP were given PEEP 0 or 5 cmH 2O for ventilation after tracheal intubation until the end of the operation. Patients in Group P were given individualized PEEP titration ventilation strategy guided by driving pressure after intubation. Blood gas analysis was performed at 5 min (T1) after tracheal intubation, 60 min (T3) after operation, and 5 min (T4) after operation. PaO 2, PaCO 2, and dynamic compliance (Cdyn) were recorded. The optic nerve sheath diameter (ONSD) was measured before anesthesia induction (T0), after PEEP titration in group P (T2, 10 min after ventilation in group 0 PEEP and 5 PEEP) and at T4; Serum neuron specific enolase (NSE) concentration was measured by ELISA before and 1 day and 3 days after operation; The occurrence of nervous system complications (intracranial infection, intracranial hypertension, epilepsy, brain edema, etc.) within 30 days after operation was followed up. Results:Compared with group 0 PEEP and 5 PEEP, Cdyn and PaO 2 in group P increased at T3-4 ( P<0.05), ONSD was not significantly different among the three groups ( P>0.05), NSE in group P decreased significantly at 1 and 3 days after operation, and the incidence of neurological complications in the three groups was not significantly different at 30 days after operation ( P>0.05). Conclusions:Individualized PEEP ventilation strategy guided by driving pressure can help improve lung and brain function in TBI patients.

Hypoxemia is a common complication of pneumonia, asthma, and bronchopulmonary dysplasia in children.Rapid identification of hypoxemia is of great significance for the disposal and management of critical children.Pulse oximetry is recognized by the World Health Organization as the best way to monitor hypoxemia in children, and it can monitor pulse oxygen saturation noninvasively and continuously.Based on the related literature at home and abroad, combined with the clinical needs of pediatrics, the " Expert consensus on clinical application of pulse oximetry in children" is formulated to improve the understanding of pediatricians and nurses on the application in pediatric clinical practice, principle, operation techniques, and limitations of pulse oximetry.

Objective:To systematically review and evaluate the safety and efficacy of high-flow nasal oxygen (HFNO) for pre-oxygenation before anesthesia induction.Methods:Pubmed, Cochrane Library, Embase, China National Knowledge Infrastructure, Wanfang Database, China Science and Technology Journal Database and China Biomedical Literature Database were searched from inception to March 2022.All randomized controlled trials comparing HFNO and facemask ventilation for pre-oxygenation before anesthesia induction were collected.Two researchers independently assessed the quality of trials and extracted data.The primary outcome was the safe apnea time, the secondary outcomes were the lowest SpO 2 during intubation, oxygenation-related complications, patient comfort, PaO 2 and PaCO 2 before and after pre-oxygenation and after intubation.Meta-analysis was performed using RevMan 5.4 software. Results:Seventeen randomized controlled trials involving 843 patients were included in this meta-analysis.The results of meta-analysis showed that the safe apnea time was significantly longer ( MD=67.61, 95% CI 5.94-129.28, P=0.03), the lowest SpO 2 was higher during tracheal intubation ( MD=3.27, 95% CI 2.25-4.29, P<0.01), and PaO 2 was higher after pre-oxygenation ( MD=54.39, 95% CI 9.32-99.46, P=0.02) in the patients using HFNO than those using facemask ventilation.There were no statistically significant differences in the other outcomes ( P>0.05). Conclusions:HFNO for pre-oxygenation before anesthesia induction can significantly prolong the safe apnea time, increase the lowest SpO 2 during tracheal intubation, and improve the levels of PaO 2 after pre-oxygenation, and HFNO does not affect the patient′s comfort or increase the development of preoxygenation-related complications when compared with facemask ventilation.

Objective:To compare the effects of different fractions of inspired O 2 (FiO 2) during general anesthesia induction on perioperative pulmonary function in patients undergoing gynecological laparoscopic surgery. Methods:A total of 100 patients, aged 30-64 yr, with body mass index<30 kg/m 2, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, scheduled for elective total laparoscopic hysterectomy, were divided into 4 groups ( n=25 each) using a random number table method: group A, group B, group C and group D. In A, B, C and D groups, FiO 2 was 40%, 60%, 80% and 100%, respectively.Immediately after the establishment of electrocardiogram monitoring after entering the operation room (T 0), immediately after tracheal intubation (T 1), immediately after creation of pneumoperitoneum (T 2), at 30 min of pneumoperitoneum (T 3), immediately before tracheal intubation (T 4) and at 15 min after tracheal intubation (T 5), ventral (ROIⅠ), middle ventral (ROIⅡ), middle dorsal (ROIⅢ) and dorsal (ROI Ⅳ) lung ventilation were recorded using electrical impedance tomography.The impedance ratio (IR) was calculated and the safety time without ventilation was recorded.Blood samples were collected from the radial artery at T 0-2 and T 5 for blood gas analysis, arterial oxygen partial pressure (PaO 2) and arterial carbon dioxide partial pressure (PaCO 2) were recorded, and oxygenation index (OI) was calculated.The occurrence of pulmonary complications within 3 days after operation was recorded. Results:Compared with group D, the ventilation in ROIⅠ and ROIⅡwas significantly increased, the ventilation in ROIⅢ and ROIⅣ was decreased, and IR was increased at T 1 and T 2 in A, B and C groups, PaO 2 and OI were decreased at T 1, and the safety time without ventilation was prolonged in A and B groups, and PaO 2 was decreased, OI was increased at T 1 ( P<0.05), and no significant was change in the safety time without ventilation in group C ( P>0.05). There was no significant difference in the incidence of pneumoperitoneum among the 4 groups ( P>0.05). Conclusion:During general anesthesia induction, 80% FiO 2 has the least effect on lung function in the patients undergoing gynecological laparoscopic surgery.

Objective:To evaluate the effect of dexmedetomidine on the activity of nucleotide-binding oligomerization domain-like receptor containing pyrin domain (NLRP3) inflammasome in ventilator-induced lung injury (VILI) in mice.Methods:Eighty-four male SPF C57BL/6J mice, weighing 25-30 g, aged 2-3 months, were divided into 3 groups ( n=28 each) using a random number table method: control group (C group), VILI group and dexmedetomidine group (D group). The mice were tracheostomized and spontaneous breathing was maintained in group C, while the other mice were tracheostomized and mechanically ventilated for 4 h in VILI and D groups.Dexmedetomidine was infused in a loading dose of 1.0μg/kg for 20 min before intubation followed by continuous infusion of 1.0 μg·kg -1·h -1 for 4 h in group D. Blood samples were taken from the femoral artery for blood gas analysis before intubation and at 1, 2 and 4 h of mechanical ventilation (T 1-4), and PaO 2 was recorded for detection of PaO 2.Eight mice were selected at T 4 and sacrificed, and the broncho-alveolar lavage fluid (BALF) was collected for determination of the concentration of total protein, interleukin-1β (IL-1β) and interleukin-18 (IL-18). The lung tissues were removed for microscopic examination of pathologic changes which were scored and for determination of the wet to dry weight (W/D) ratio, expression of IL-1β and IL-18 mRNA (by real-time polymerase chain reaction), and expression of NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), and caspase-1 (by Western blot). The other 20 mice in each group were observed for the 24-h survival rate. Results:Compared with group C, PaO 2 at T 3 and T 4 and 24-h survival rate were significantly decreased, and the lung injury score, W/D ratio, and concentrations of total protein, IL-1β, and IL-18 in BALF were increased, and the expression of NLRP3, ASC, caspase-1, IL-1β mRNA and IL-18 mRNA was up-regulated in VILI and D groups ( P<0.05). Compared with group VILI, the 24-h survival rate was significantly increased, the lung injury score, W/D ratio, and concentrations of total protein, IL-1β, and IL-18 in BALF were decreased, and the expression of NLRP3, ASC, caspase-1, IL-1β mRNA and IL-18 mRNA was down-regulated in group D ( P<0.05). Conclusion:The mechanism by which dexmedetomidine attenuates VILI may be related to inhibiting NLRP3 inflammasome activity in mice.

Objective To identify the effect of stereotactic body radiation therapy (SBRT) on the survival of patients with recurrent pancreatic cancer after surgery.Methods The data of 104 patients with recurrent pancreatic cancer after surgery who underwent SBRT in the Department of Radiation Oncology of Changhai Hospital,Navy Medical University from February 2012 to December 2016 were retrospectively analyzed.The prescription doses ranged from 35-40 Gy/4-8 f.Survival analysis was performed using the Kaplan-Meier method,and relevant factors affecting patients' survival were screened by the Cox proportional hazards model.Results The median overall survival (OS) and progression free survival (PFS) was 12.5 (11.0-14.0) months and 7.3 (6.0-8.7) months,respectively,while the 1-year rate of OS and PFS was 55.8％ and 22.1％,respectively.Multivariate analysis indicated that tumor stage,biological effect dose (α/β =10,BED10),the decrease of CA19-9 level after treatment,and follow-up chemotherapy were all related factors affecting overall survival;tumor stage,BED10,the degree of pain relief and the decrease of CA19-9 level after treatment were related factors affecting PFS.Conclusions Patients suffering recurrent pancreatic cancer with early tumor stage,normal CA19-9 level and mild pain before treatment could be better treated by SBRT,BED10 ≥60 Gy and follow-up chemotherapy after radiotherapy can prolong the survival of patients.

OBJECTIVETo evaluate the effect of transcutaneous electrical acupoint stimulation (TEAS) on the quality of recovery during the early period after laparoscopic cholecystectomy and the dosage of anesthetic and analgesic.

METHODSOne hundred patients who received laparoscopic cholecystectomy with gradeⅠand Ⅱ of American Society of Anesthesiologists (ASA) criteria were randomly assigned into an observation group and a control group according to random number table, 50 cases in each group. The patients in the two groups were treated with conventional endotracheal intubation anesthesia, anesthesia induction and maintenance. The patients in the observation group were treated with TEAS (2 Hz/100 Hz, 8 to 12 mA) at bilateral Hegu (LI 4) and Neiguan (PC 6), as well as Zusanli (ST 36) and the non-acupoint 2 outboard from Zusanli (ST 36) from 30 min before anesthesia induction to the end of operation. The patients in the control group were applied by stimulation electrode in the corresponding points without electrical stimulation. The dosage of intraoperative remifentanil and the analgesic dosage of dezocine for postoperation were recorded. The recovery time, extubation time, the changes of heart rate (HR) and mean arterial pressure (MAP) during extubation were recorded. The quality of recovery was assessed by the quality of recovery-40 questionnaire (QoR-40) 1 day before surgery (T)，and 4 h (T), 8 h (T), 24 h (T), 48 h (T) after surgery. The patient's cognitive function was assessed by mini-mental state examination (MMSE) scale at the 5 time points. The incidences of postoperative nausea and vomiting were recorded at T through T.

RESULTSThe dosages of intraoperative remifentanil and dezocine in the observation group were less than those in the control group; the recovery time and extubation time were shorter than those in the control group; the HR of extubation was lower than that in the control group (all <0.05). There was no statistic difference about MAP between the two groups (>0.05). Compared with T, the total scores of QoR-40 decreased in the two groups at T, T, T (all <0.05), and the total scores in the observation group were higher than those in the control group (all <0.05). The emotional state, physical comfort, psychological support, self-care ability, pain scores at T in the observation group and at T, T, T in the control group were lower than those at T (all <0.05). The emotional state, physical comfort, psychological support, self-care ability, pain scores in the observation group were higher than those in the control group at T, T, T (all <0.05). Compared with T, the MMSE scores in the two groups decreased at T and T (all <0.05). At T, T, T, the MMSE scores in the observation group were higher than those in the control group (all <0.05). At T and T, the incidence rates of nausea and vomiting were 22.0% (11/50), 12.0% (6/50) respectively in the observation group, which were lower than 32.0% (16/50) and 24.0% (12/50) in the control group (both <0.05). At T and T, the incidence rates of nausea and vomiting were 6.0% (3/50), 2.0% (1/50) respectively in the observation group, which were not significantly different from 8.0% (4/50) and 4.0% (2/50) in the control group (both >0.05).

CONCLUSIONTEAS can improve the quality of recovery during the early period after laparoscopic cholecystectomy and reduce the dosage of anesthetic and analgesic.

Objective To propose the method of dose distribution calculated by one-step optimization with 7 shells (Cao method) and compare with that by three-step optimization with 4 shells (Blanck method) and CyberKnife treatment plans for pancreatic cancer. Methods 20 cases of pancreatic cancer who underwent CyberKnife treatment were retrospectively analyzed,and CT was performed to localize and delineate the target area and endangering organs. Dosage was optimized and evaluated with Blanck method and Cao method. The planning target volume (PTV) conformity index (CI), new conformity index (nCI), homogeneity index (HI),gradient index (GI), coverage, dose-volume and doses to organs at risk were compared. Results Compared with Blanck method, CI (1.11 ± 0.05 vs 1.15 ± 0.05), nCI (1.20 ± 0.06 vs 1.23 ± 0.06), coverage [(92.48 ± 1.85)% vs (93.53 ± 2.15)%], volumes encompassed by 100% and 30% prescription dose line (36.46 ± 16.64 vs 38.19 ± 17.68; 286.19 ± 126.52 vs 320.93 ± 154.82) and monitor unit (56 369 ± 20 019 vs 57 814 ± 20 531) were significantly decreased,while GI was increased (3.22 ± 0.19 vs 3.11 ± 0.19), and all the differences were statistically significant (P<0.05). Additionally, Dmax of the intestine (21.17 ± 2.90 vs 20.63 ± 3.13), D10cc of the stomach (12.78 ± 2.57 vs 13.11 ± 2.43), D5ccof the duodenum (11.01 ± 3.45 vs 11.50 ± 3.25), D10ccof the duodenum (9.30 ± 3.31 vs 9.78 ± 3.07) and D0.35ccof the spinal cord (6.09 ± 0.98 vs 6.59 ± 0.92) were all significantly decreased (P<0.05). No significant differences were found on other parameters. Conclusions Better dose distributions are accessible by one-step optimization with 7 shells in CyberKnife treatment plans for pancreatic cancer.