Objective:To evaluate the effect of individualized positive end-expiratory pressure (PEEP) titration based on open-lung strategy on the intraoperative thoracic fluid content (TFC) in elderly patients undergoing transurethral ultrasound-guided laser-induced prostatectomy (TULIP).Methods:Eighty-six American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, patients, aged 65-80 yr, with body mass index of 18-28 kg/m 2, scheduled for elective TULIP, were divided into 2 groups ( n=43 each) by the random number table method: fixed PEEP group (group C) and individualized PEEP titration group (group P). PEEP was set at 4 cmH 2O after routine mechanical ventilation in group C. Patients underwent pulmonary recruitment maneuvers combined with individualized PEEP titration during surgery in group P. TFC was measured using a non-invasive cardiac output monitor at 5 min after tracheal intubation (T 0), 30 min after PEEP titration and ventilation (T 1), 5 min before surgery (T 2), and 5 min before leaving the recovery room (T 3). Cardiac output, oxygenation index and stroke volume index were recorded from T 0-T 2, arterial blood gas analysis was simultaneously performed to record peak airway pressure and dynamic lung compliance, and oxygenation index was calculated. The duration of postanesthesia care unit stay, pulmonary complications within 7 days after surgery, and length of hospital stay were also recorded. Results:Eighty-three patients were finally included, with 42 in group C and 41 in group P. Compared with group C, TFC was significantly decreased at T 1-T 3, cardiac index, cardiac output and stroke volume index were decreased at T 1, dynamic lung compliance, PaO 2 and oxygenation index were increased at T 1 and T 2, PaCO 2 was decreased, the incidence of postoperative pulmonary complications was reduced, and the duration of postanesthesia care unit stay and postoperative length of hospital stay were shortened in group P ( P<0.05). Conclusions:Individualized PEEP titration based on open-lung strategy can effectively decrease TFC and improve intraoperative oxygenation and prognosis in elderly patients undergoing TULIP.

Objective:To evaluate the effect of transnasal humidified rapid insufflation ventilatory exchange (THRIVE) on regional cerebral oxygen saturation (rScO 2) during induction of general anesthesia in patients undergoing traumatic brain injury (TBI) emergency surgery. Methods:A prospective randomized controlled trial was conducted. The TBI emergency general anesthesia patients who underwent intracranial hematoma removal surgery at the Northern Jiangsu People's Hospital from January to July in 2023 were enrolled. The patients were divided into a conventional mask ventilation group and a THRIVE group using a random number table method. The patients in the conventional mask ventilation group were anesthetized and induced to pre oxygenate without positive pressure ventilation in the front mask for 10 minutes, with an oxygen flow rate of 8 L/min and an fraction of inspired oxygen (FiO 2) of 1.00. After anesthesia induction for about 90 s, tracheal intubation was performed after the muscle relaxant took effect (patient's jaw muscle was relaxed). The patients in the THRIVE group were pre oxygenated with THRIVE for 10 minutes, with an oxygen flow rate of 30 L/min and a FiO 2 of 1.00. During anesthesia induction, the oxygen flow rate was increased to 50 L/min, and anesthesia induction medication was used. The lower jaw of patient was supported with both hands to maintain airway patency, and the patient's mouth was kept closed throughout the process. After the muscle relaxant took effect (the patient's jaw muscle was relaxed), tracheal intubation was performed. At the time of patient entering the operating room, 10 minutes of pre oxygenation, and immediately after successful intubation, rScO 2 was measured on the surgical and non-surgical sides. At the same time, ultrasound was used to measure the cross-sectional area (CSA) of the gastric antrum and arterial blood gas analysis was performed. The partial pressure of end-tidal carbon dioxide (P ETCO 2) during the first mechanical ventilation after successful tracheal intubation, the incidence of hypoxemia [pulse oxygen saturation (SpO 2) < 0.95] during tracheal intubation, as well as prognostic indicators such as the length of intensive care unit (ICU) stay, total length of hospital stay, and Glasgow outcome scale (GOS) score at discharge were recorded. Results:During the study period, a total of 70 TBI patients underwent emergency general anesthesia surgery, of which 2 patients died postoperatively, 2 patients were unable to cooperate with closed mouth breathing, and 3 patients had poor ultrasound image acquisition in the gastric antrum, all of whom were excluded. A total of 63 patients were ultimately enrolled, including 32 in the conventional mask ventilation group and 31 in the THRIVE group. There were no statistically significant differences in gender, age, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, Glasgow coma scale (GCS) score, optic nerve sheath diameter (ONSD), baseline vital signs, fasting situation, anesthesia time, surgical time, and intraoperative blood loss between the patients in the two groups, indicating comparability. When entering the operating room, there was no statistically significant difference in rScO 2 on the surgical and non-surgical sides, and blood gas analysis indexes arterial partial pressure of oxygen (PaO 2) and arterial partial pressure of carbon dioxide (PaCO 2) between the patients in the two groups. When pre oxygenated for 10 minutes, both the surgical and non-surgical sides rScO 2 levels in the THRIVE group were significantly higher than those in the conventional mask ventilation group (surgical side: 0.709±0.036 vs. 0.636±0.028, non-surgical side: 0.791±0.016 vs. 0.712±0.027, both P < 0.01), and the PaO 2 was significantly increased [mmHg (1 mmHg≈0.133 kPa): 450.23±60.99 vs. 264.88±49.33, P < 0.01], PaCO 2 was significantly reduced (mmHg: 37.81±3.65 vs. 43.59±3.76, P < 0.01), and the advantage continues tilled immediately after successful intubation. There was no statistically significant difference in CSA at each time point of ultrasound examination between the two groups. Compared with the conventional mask ventilation group, the patients in the THRIVE group showed a significant decrease in P ETCO 2 during the first mechanical ventilation after successful tracheal intubation (mmHg: 43.10±2.66 vs. 49.22±3.31, P < 0.01), and the incidence of hypoxemia during tracheal intubation was also significantly reduced [0% (0/31) vs. 28.12% (9/32), P < 0.01]. In terms of prognostic indicators, there was no statistically significant difference in the length of ICU stay and total length of hospital stay between the patients in the conventional mask ventilation group and the THRIVE group [length of ICU stay (days): 10 (9, 10) vs. 10 (9, 11), total length of hospital stay (days): 28.00 (26.00, 28.75) vs. 28.00 (27.00, 29.00), both P > 0.05]. However, the proportion of patients in the THRIVE group with a good prognosis at discharge (GOS score > 3) was significantly higher than that in the conventional mask ventilation group [35.5% (11/31) vs. 12.5% (4/32), P < 0.05]. Conclusion:THRIVE can significantly increase rScO 2 during anesthesia induction in TBI emergency surgery patients and improve their neurological function prognosis.

Objective:To evaluate the accuracy of inferior vena cava (IVC) parameters measured by ultrasound in predicting post-induction hypotension(PIH) in patients undergoing general anesthesia using a meta-analysis.Methods:Databases such as China National Knowledge Infrastructure, Wanfang, China Science and Technology Journal Database, PubMed, Cochrane Library and Embase were searched for diagnostic clinical trials that involved IVC parameters such as IVC collapsibility index (IVCCI), maximum and minimum IVC diameters (dIVCmax, dIVCmin) measured by ultrasound that predicted PIH from inception to May 2022. Primary outcomes were sensitivity, specificity, and the area under the receiver operating characteristic curve of each parameter. The meta regression analysis and subgroup analysis were used to explore the sources of heterogeneity.Results:Nineteen articles were ultimately included ( n=1 750). The sensitivity and specificity of IVCCI in predicting PIH were 0.73 and 0.82 respectively, and the area under the summary receiver operating characteristic curve(AUSROC) was 0.85, and the prediction threshold of IVCCI was (42.5±6.8)%. The sensitivity and specificity of dIVCmax in predicting PIH were 0.46 and 0.74 respectively, and the AUSROC was 0.64. The sensitivity and specificity of dIVCmin in predicting PIH were 0.69 and 0.66 respectively, and the AUSROC was 0.72. In subgroup analysis, the AUSROC of IVCCI in predicting PIH in etomidate subgroup and non-immediate measurement before induction subgroup was 0.92 and 0.71 respectively. The AUSROC of IVCCI was all between 0.8 and 0.9 in propofol group, fentanyl group, sufentanil group, ARB/ACEI group, unlimited surgical types group, and combined with vascular diseases group and other subgroups. Conclusions:IVCCI measured by ultrasound can moderately predict PIH, and dIVCmax and dIVCmin have low accuracy in predicting PIH. Immediate measurement before induction and use of etomidate can improve the predictive accuracy of IVCCI. The predictive accuracy of IVCCI is not affected by the type of opioid drugs, type of surgery, use of ARB/ACEI antihypertensive drugs or vascular diseases.

Objective To evaluate the role of P2Y₁₂ receptor in microglia in central post-stroke pain (CPSP) in mice and its mechanism. Methods Thirty-two specific pathogen-free(SPF)-grade male C57BL/6J mice were selected, aged 7 to 8 weeks, weighing 25 to 30 g, were divided into four groups using a random number table method: C group (sham operation group, n=8), CPSP group (n=8), CPSP-M group (CPSP plus P2Y₁₂ receptor inhibitor MRS2395, n=8) and C-M group (sham operation plus P2Y₁₂ receptor inhibitor MRS2395, n=8). CPSP model was induced by injecting 10 nL type Ⅳ collagenase(0.001 U/nL) into the right ventral posterior medial nucleus andventral posterior lateral nucleus. MRS2395(1.5 mg/kg) was injected intraperitoneally at 30 min before model preparation in CPSP-M group and C-M group and then injected once a day for 5 consecutive days, mice in C group and CPSP group were given saline at the same volume. Before the modeling (T₀) and 3, 7 and 14 days (T₁, T₂, T₃) after the establishment of the model, the thermal withdrawal latency (TWL), cold withdrawal latency (CWL) and paw withdrawal frequency (PWF) were measured. The mice were then sacrificed and the brain tissues were obtained for observing the location of P2Y₁₂receptor by double immunofluorescence staining and the pathological changes by HE staining, and for determination of the expression levels of P2Y₁₂ receptor, toll-like receptor 4 (TLR4), phospho-nuclear factor-κB p65 (p-NF-κB p65) and NF-κB p65 by western blot. Results P2Y₁₂ receptor was co-localized only with microglia, but not with neurons or astrocytes in brain tissue of CPSP group. Compared with C group, the TWL and CWL were significantly reduced and the PWF was significantly increased at T₁ to T₃, cerebral injury was aggravated significantly and the expressions of P2Y₁₂ receptor, TLR4 and p-NF-κB p65 in brain tissue were up-regulated in CPSP group and CPSP-M group (P < 0.05). There was no statistically significant difference between C group and C-M group in the above indicators (P>0.05). Compared with CPSP group, the TWL and CWL were significantly prolonged and the PWF was significantly reduced at T₁ to T₃, cerebral injury was relieved significantly and the expressions of P2Y₁₂ receptor, TLR4 and p-NF-κB p65 in brain tissue were down-regulated in CPSP group and CPSP-M group (P < 0.05). Conclusion P2Y₁₂ receptors in microglia may be involved in the development of CPSP by activating TLR4/NF-κB signaling pathway in mice.

Objective:To observe the effect of ventilator-induced lung injury (VILI) on blood-brain barrier permeability in rats.Methods:Forty-eight healthy clean male Sprague-Dawley (SD) rats were randomly divided into sham operation (Sham) group, low tidal volume (LVT) mechanical ventilation group (LVT group), normal tidal volume (NVT) mechanical ventilation group (NVT group) and high tidal volume (HVT) mechanical ventilation group (HVT group) with 12 rats in each group. After anesthesia, rats in the Sham group were intubated and kept spontaneous breathing. The rats in different tidal volume (VT) groups were mechanically ventilated by endotracheal intubation with VT of 6 mL/kg (LVT group), 10 mL/kg (NVT group), and 20 mL/kg (HVT group), respectively. The inspiration-expiration ratio of the three groups was 1∶1, the ventilation frequency was 40 times/min, and the ventilation time was 3 hours. At the end of the experiment, the bronchoalveolar lavage fluid (BALF) of rats was collected, and the levels of pro-inflammatory factors [tumor necrosis factor-α (TNF-α), interleukins (IL-1β and IL-6)] in BALF were detected by enzyme-linked immunosorbent assay (ELISA). The lung tissues of rats were collected, and the lung wet/dry weight (W/D) ratio was calculated. The pathological changes of lung tissues were observed under light microscopy after hematoxylin-eosin (HE) staining, and lung injury scores were performed. The brain tissue of rats was taken to measure the brain water content, and the Evans blue (EB) content of brain tissue was measured to reflect the permeability of the blood-brain barrier. The tight junction proteins in the brain tissues were detected by Western blotting.Results:After 3 hours of mechanical ventilation, with the increase of VT, the degree of lung injury in VILI rats gradually increased. When VT reached 20 mL/kg, lung tissue structure was significantly injured, alveolar wall edema, alveolar congestion, lung interstitial thickening, a large number of inflammatory cells infiltrated, and the lung injury score, lung W/D ratio, and the levels of TNF-α, IL-1β and IL-6 in BALF were significantly higher than those in the Sham group [lung injury score: 10.6±1.1 vs. 1.4±1.0, lung W/D ratio: 6.6±0.8 vs. 3.7±0.6, TNF-α(ng/L): 832.9±97.9 vs. 103.8±23.3, IL-1β (ng/L): 68.9±14.1 vs. 15.7±2.6, IL-6 (ng/L): 70.8±16.4 vs. 20.3±5.4, all P < 0.05]. Lung injury in rats was accompanied by aggravating brain injury. When VT reached 20 mL/kg, brain water content and EB content in brain tissue were significantly higher than those in the Sham group [brain water content: (85.4±3.6)% vs. (68.7±2.7)%, EB content in brain tissue (μg/g): 887±78 vs. 97±14, both P < 0.05], and the protein expressions of claudin-5, occluding and zonula occluden-1 (ZO-1) in the brain tissue were significantly lower than those in the Sham group [claudin-5 protein (claudin-5/β-actin): 0.67±0.12 vs. 1.45±0.19, occludin protein (occludin/β-actin): 0.48±0.11 vs. 0.99±0.21, ZO-1 protein (ZO-1/β-actin): 0.13±0.03 vs. 0.63±0.12, all P < 0.05]. Conclusion:VILI can induce brain edema and increase blood-brain barrier permeability in rats, which may be related to the down-regulation of tight junction protein expression in the brain tissue.

Objective:To evaluate the effect of open-lung strategy (OLS) on postoperative delirium (POD) in elderly patients undergoing laparoscopic surgery.Methods:Seventy-four elderly patients of both sexes, aged 65-80 yr, with body mass index of 18.5-30.0 kg/m 2, of American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, undergoing elective laparoscopic radical rectal cancer or radical prostate cancer surgery under general anesthesia, were divided into 2 groups ( n=37 each) by the random number table method: OLS group and non-OLS (NOLS) group. Patients in OLS group received small tidal volume ventilation, recruitment maneuvers, and individualized positive end-expiratory pressure. Fixed positive end-expiratory pressure 5 cmH 2O was given in NOLS group. Cerebral regional oxygen saturation (rSO 2), pH value, PaO 2, PaCO 2 and PaO 2/FiO 2 were recorded before induction of anesthesia (T 0, baseline value), at 10 min after tracheal intubation (T 1), at 1 and 2 h after pneumoperitoneum (T 2, 3) and at 10 min after extubation (T 4). The levels of serum interleukin-6 (IL-6), IL-10 and calcium-binding protein (S100β) were measured by enzyme-linked immunosorbent assay before surgery, at the end of surgery, and at 1 day after surgery. The development of POD was assessed using the delirium assessment scale at 1-3 days after surgery. Results:Compared with NOLS group, the pH value was significantly decreased at T 3, PaCO 2 was increased, PaO 2, PaO 2/FiO 2 and rSO 2 were increased at T 2-4, serum IL-6 and S100β concentrations were decreased after surgery and at 1 day after surgery, the serum IL-10 concentration was increased, and the incidence of POD was decreased in OLS group ( P<0.05). Conclusions:OLS can increase rSO 2, reduce the systemic inflammatory response, and decrease the risk of POD in elderly patients undergoing laparoscopic surgery.

Objective:To evaluate the relationship between silent information regulator 1 (SIRT1) and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis.Methods:One hundred and fifty-two SPF-grade male C57BL/6J mice, aged 8 weeks, weighing 23-27 g, were divided into 4 groups ( n=38 each) using a random number table method: sham operation group (C group), sepsis group (S group), curcumin group (Cur group) and curcumin plus SIRT1 inhibitor EX527 group (CE group). Curcumin 200 mg/kg was administered by intragastric gavage every day in Cur group. Curcumin 200 mg/kg was administered by intragastric gavage every day and EX527 5 mg/kg was intraperitoneally injected in CE group. The equal volume of solvent dimethyl sulfoxide (DMSO) was given in C group and S group. Sepsis model was developed by cecal ligation and puncture (CLP) after 5 days of consecutive administration in anesthetized animals. Twenty mice in each group were randomly selected to observe the survival condition within 7 days after CLP. The bronchoalveolar lavage fluid (BALF) was collected at 24 h after developing the model to determine the concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6 and IL-18 (by enzyme-linked immunosorbent assay), and the lung tissues were obtained for microscopic examination of the pathological changes which were scored and for determination of wet-to-dry lung weight (W/D) ratio, contents of glutathione (GSH), malondialdehyde (MDA) and iron (by colorimetry), and expression of SIRT1, glutathione peroxidase 4 (GPX4) and Acyl-CoA synthetase long chain family member 4 (ACSL4) (by Western blot). Results:Compared with C group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH in lung tissues was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in S group ( P<0.05). Compared with S group, the 7-day survival rate after CLP was significantly increased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were decreased, the content of GSH was increased, the contents of MDA and iron were decreased, the expression of SIRT1 and GPX4 was up-regulated, and the expression of ACSL4 was down-regulated in Cur group ( P<0.05). Compared with Cur group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in CE group ( P<0.05). Conclusions:The mechanism by which curcumin attenuates acute lung injury may be related to activation of SIRT1 and further inhibition of ferroptosis in mice.

Venous thromboembolism (VTE) is a complication in children with acute lymphoblastic leukemia (ALL). The Chinese Children's Cancer Group-ALL-2015 protocol was carried out in China, and epidemiology, clinical characteristics, and risk factors associated with VTE were analyzed. We collected data on VTE in a multi-institutional clinical study of 7640 patients with ALL diagnosed in 20 hospitals from January 2015 to December 2019. First, VTE occurred in 159 (2.08%) patients, including 90 (56.6%) during induction therapy and 108 (67.92%) in the upper extremities. T-ALL had a 1.74-fold increased risk of VTE (95% CI 1.08-2.8, P = 0.022). Septicemia, as an adverse event of ALL treatment, can significantly promote the occurrence of VTE (P < 0.001). Catheter-related thrombosis (CRT) accounted for 75.47% (n = 120); and, symptomatic VTE, 58.49% (n = 93), which was more common in patients aged 12-18 years (P = 0.023), non-CRT patients (P < 0.001), or patients with cerebral thrombosis (P < 0.001). Of the patients with VTE treated with anticoagulation therapy (n = 147), 4.08% (n = 6) had bleeding. The VTE recurrence rate was 5.03% (n = 8). Patients with VTE treated by non-ultrasound-guided venous cannulation (P = 0.02), with residual thrombus (P = 0.006), or with short anticoagulation period (P = 0.026) had high recurrence rates. Thus, preventing repeated venous puncture and appropriately prolonged anticoagulation time can reduce the risk of VTE recurrence.
Humans ; Child ; Venous Thromboembolism/etiology* ; East Asian People ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/epidemiology* ; Risk Factors ; Thrombosis/chemically induced* ; China/epidemiology* ; Anticoagulants/adverse effects* ; Recurrence

Objective:To study whether cisplatin may induce apoptosis in the pericytes of cochlear stria vascularis and underlying mechanisms.Methods:Twenty male C57BL/6J mice aged 6-8 weeks were divided into control group and a cisplatin group. Primary cultured mouse cochlear vascular peristriatal cells were identified and divided into control group, cisplatin group, and N-acetylcysteine+cisplatin group. Auditory brainstem response (ABR) was used to detect hearing in mice. Hematoxylin eosin (HE) staining was used to observe morphological changes in the stria vascularis of the cochlea. The total superoxide dismutase (SOD) activity test kit (WST-1 method) and thiobarbituric acid (TBA) method were used to detect SOD activity and Malondialdehyde (MDA) content, respectively. DCFH-DA fluorescence probe was used to detect the content of reactive oxygen species in peripheral cells. Hoechst 33 342 and flow cytometry were used to detect the apoptosis rate of pericytes. Immunofluorescence technology was used to detect the distribution and expression of apoptosis related proteins in pericytes of cochlear stria vascularis. Immunohistochemistry and Western blotting (WB) were used to detect the expression of apoptosis-and mitochondrial-related proteins. Mito SOX TM-red and JC-1 were used to detect the mitochondrial function of pericytes. Evans blue staining was used to observe the permeability of the blood labyrinth barrier (BLB). Statistical analysis was conducted using SPSS 18.0 software. Results:Compared with the control group, the cisplatin group significantly increased in the hearing threshold ( t=4.72, P<0.01), Ⅰ-wave latency ( t=12.25, P<0.05), and the levels of oxidative stress in the cochlea and pericytes ( t=38.34, P<0.01), and also cisplatin caused disorder and contraction of the cochlear stria vascularis structure, increased BLB permeability [Evans blue leakage (1.08±0.42) AU vs (0.55±0.23) AU, t=4.64, P<0.05], with a statistically significant difference, enhanced the expressions of apoptotic proteins c-Caspase-3 ( t=5.01, P<0.01) and Bax ( t=6.33, P<0.01) in the peristriatal cells of cochlear blood vessels in mice treated with cisplatin increased. And cisplatin can induce apoptosis of primary cultured pericytes and up-regulate the expression of c-Caspase-3 and Bax ( P<0.05). The NAC+cisplatin group partially reversed cisplatin-induced pericyte apoptosis ( P<0.05). Cisplatin caused damage to the mitochondrial function of peripheral cells, and induced the release of apoptosis-inducing factor (AIF) and cytochrome C (cyt-c) into the cytoplasm ( P<0.05). The NAC+cisplatin group partially reversed cisplatin induced pericyte apoptosis ( P<0.05) and mitochondrial damage ( P<0.05). Conclusion:Cisplatin can increase the level of oxidative stress in the cochlea and cause mitochondrial pathway apoptosis in C57BL/6J mouse cochlear vascular peristriatal cells.

Objective:To explore the influencing factors of bowel preparation quality in hospitalized elderly patients, and to find the appropriate waiting time from the end of bowel preparation to the beginning of colonoscopy.Methods:Baseline and clinical data of elderly patients over 60 years old who underwent colonoscopy in the Tenth People′s Hospital, Tongji University from February 2021 to August 2021 were collected. Multivariate analysis was used to screen the factors that might affect the quality of bowel preparation in hospitalized elderly patients. Patients were grouped according to waiting time before colonoscopy. After eliminating confounding factors using propensity matching analysis, the difference of bowel preparation quality among groups was compared.Results:251 patients were included in the study. Multivariate analysis revealed that, hypertension ( OR=3.530, 95% CI 1.295-9.618), chronic constipation ( OR=3.302,95% CI 1.132-9.632), dietary compliance ( OR=0.161, 95% CI 0.070-0.371), medication and drinking water compliance ( OR=0.167, 95% CI 0.070-0.397), exercise compliance after medication ( OR=2.245, 95% CI 1.040-4.845), The frequency of defecation after medication ( OR=0.446, 95% CI 0.308-0.647) and waiting time ( OR=0.537, 95% CI 0.387-0.745) were important factors affecting the quality of bowel preparation in hospitalized elderly patients ( P<0.05). There were differences in bowel preparation quality between groups of waiting times. The overall quality of bowel preparation in 120-180 min group was significantly better than that in 241-300 min group, 301-360 min group and>360 min group ( P<0.05). The overall quality of bowel preparation in 181-240 min group was better than that in >360 min group ( P<0.05). There were no significant differences among other groups( P>0.05). The scores of cecum and ascending colon were the best in 120-180 min group, and the cleanliness of descending colon, sigmoid colon and rectum was significantly higher in 241-300 min group, 301-360 min group and > 360 min group. The scores of descending colon, sigmoid colon and rectum showed that the intestinal preparation quality of 181-240 min group was better than that of 301-360 min group and > 360 min group. Conclusions:The best examination time for elderly patients is about 180 minutes after bowelpreparation. Medical workers should flexibly guide the medication time to ensure that patients are in the best clean state of intestinal tract during examination.