Determination of the 90% Effective Dose of Dexmedetomidine for Treating Postoperative Catheter­related Bladder Discomfort During Recovery: An Open-label, Single-group Study.

PURPOSE: Catheter-related bladder discomfort (CRBD) is an unpleasant experience for patients during postoperative recovery. Dexmedetomidine is an effective therapy for CRBD; however, little is known about dexmedetomidine administration for treating CRBD during recovery. This study was conducted to determine the 90% effective dose (ED90) of dexmedetomidine to provide adequate treatment for CRBD during recovery. DESIGN: Prospective, single-blind dose-finding study. METHODS: This open-label, single-group trial included severe postoperative CRBD patients aged 18 to 80 years and the American Society of Anesthesiologists' physical status class I or II in the postanesthesia care unit. All patients were assigned to receive intravenous dexmedetomidine. The dose of dexmedetomidine was determined using the modified Dixon's up-and-down method. The first patient was treated with 0.4 mcg/kg dexmedetomidine. An increment or decrement of 0.05 mcg/kg dexmedetomidine was used based on the response of the previous patient. A successful treatment was defined as the transition from severe CRBD to mild CRBD. Probit regression was applied to calculate the ED90 of dexmedetomidine. FINDINGS: A total of 29 patients were recruited, of whom 14 patients (48.3%) underwent successful treatment. The ED90 of dexmedetomidine required for successfully treating postoperative CRBD was 0.55 mcg/kg (95% confidence interval: 0.49-1.54 mcg/kg). CONCLUSIONS: The ED90 of dexmedetomidine for the successful treatment of severe postoperative CRBD during recovery is 0.55 mcg/kg.

RDW-SD and PCT Are Potential Prognostic Factors for In-hospital Death in Patients With Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis.

PURPOSE: Our study aimed to explore potential prognostic factors in Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) patients from easily accessible laboratory data and to investigate whether the combination of these indicators with a score for toxic epidermal necrolysis (SCORTEN) can improve the predictive value. METHODS: Data from 85 SJS/TEN patients hospitalized from 2010 to 2021 were retrospectively analyzed. The primary outcome was in-hospital mortality. Univariate analysis was used to screen for laboratory indexes associated with death. Logistic regression was used to analyze significant risk factors for death. The differentiation and calibration of SCORTEN and modified score were assessed using receiver operating characteristic (ROC) curves and Hosmer-Lemeshow goodness-of-fit test. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were used to evaluate the incremental prognostic value. RESULTS: Among the 85 patients (37 males, 48 females) aged 14-88 years, the mortality rate was 11.8% (n = 10). SCORTEN had good discrimination and calibration to predict mortality in this cohort of patients (area under the ROC curve [AUC] of 0.874, 95% confidence interval [CI], 0.758-0.990; Hosmer-Lemeshow goodness-of-fit test P = 0.994). Red cell distribution width-standard deviation index (RDW-SD) > 47.9 fL and procalcitonin (PCT) > 0.67 ng/mL were significant risk factors for death. When adding the 2 factors to SCORTEN, AUC was 0.915 (95% CI, 0.833-0.997), but not statistically different compared to SCORTEN alone (P = 0.091). The NRI was 1.2 (95% CI, 0.672-1.728; P < 0.001) and the IDI was 0.09 (95% CI, 0.011-0.173; P = 0.026), still suggesting that the modified score had better discriminatory and predictive power than SCORTEN alone. The modified score also showed good calibration (Hosmer-Lemeshow goodness-of-fit test, P = 0.915). CONCLUSIONS: SCORTEN is a good predictor of mortality in SJS/TEN patients in southwest China. Combining RDW-SD > 47.9 fL and PCT > 0.67 ng/mL with SCORTEN may enhance the ability to predict prognosis.

Influence of goal-directed fluid therapy guided by the Vigileo-FloTracTM system on intestinal mucosal barrier function in elderly patients with colorectal cancer.

Introduction: Colorectal cancer is a clinically common malignancy arising in the digestive tract. Aim: To evaluate the influence of goal-directed fluid therapy (GDFT) guided by the Vigileo-FloTracTM system on intestinal mucosal barrier function in elderly patients with colorectal cancer. Material and methods: A prospective study was conducted on 106 elderly patients with colorectal cancer. They were divided into control and research groups (n = 53) using a random number table, and subjected to conventional fluid therapy and Vigileo-FloTracTM system-guided GDFT, respectively. Their intraoperative indicators, postoperative indicators, and changes of haemodynamics, oxygen metabolism, intestinal mucosal barrier function at different time points, and incidence rates of complications were compared. Results: Compared with the control group, the intraoperative urine volume, colloid fluid volume, crystalloid fluid volume, and total infusion volume were lower, and the first postoperative exhaust time, first postoperative feeding time, and hospital stay were shorter in the research group (p < 0.05). At T1 and T2, mean artery pressure, heart rate, central venous pressure, oxygen consumption, oxygen delivery, and oxygen extraction ratio in the research group were lower than in the control group, but all of them first rose and then fell in the 2 groups (p < 0.05). On the 3rd day after surgery, the levels of serum endothelin, diamine oxidase and D-lactate declined in both groups, and the decline was more obvious in the research group (p < 0.05). Conclusions: GDFT guided by the Vigileo-FloTracTM system is beneficial to the prognosis of patients by effectively decreasing fluid infusion.

Potential application of ginseng in sepsis:: Applications of ginseng in sepsis.

Sepsis and septic shock affect millions of people worldwide each year with high clinical mortality rates. At present, basic research on sepsis has emerged in an endless stream, but there are few effective clinical translation results. Ginseng, a medicinal and edible representative of Araliaceae plants, contains a variety of biologically active compounds including ginsenosides, alkaloids, glycosides, polysaccharides, and polypeptides. Neuromodulation, anticancer activity, blood lipid regulation, and antithrombotic activity have been linked to ginseng treatment. At present, basic and clinical research have suggested various applications of ginseng in sepsis. In view of the different effects of various ginseng components on the pathogenesis of sepsis, and in order to further understand and develop the possible value of ginseng in sepsis, this manuscript reviews the application of various components of ginseng in the treatment of sepsis in recent years.

Establishment and Application of a Patient-Ventilator Asynchrony Remote Network Platform for ICU Mechanical Ventilation: A Retrospective Study.

BACKGROUND: In the process of mechanical ventilation, the problem of patient-ventilator asynchrony (PVA) is faced. This study proposes a self-developed remote mechanical ventilation visualization network system to solve the PVA problem. METHOD: The algorithm model proposed in this study builds a remote network platform and achieves good results in the identification of ineffective triggering and double triggering abnormalities in mechanical ventilation. RESULT: The algorithm has a sensitivity recognition rate of 79.89% and a specificity of 94.37%. The sensitivity recognition rate of the trigger anomaly algorithm was as high as 67.17%, and the specificity was 99.92%. CONCLUSIONS: The asynchrony index was defined to monitor the patient's PVA. The system analyzes real-time transmission of respiratory data, identifies double triggering, ineffective triggering, and other anomalies through the constructed algorithm model, and outputs abnormal alarms, data analysis reports, and data visualizations to assist or guide physicians in handling abnormalities, which is expected to improve patients' breathing conditions and prognosis.

Chinese experts' consensus on the application of intensive care big data.

The development of intensive care medicine is inseparable from the diversified monitoring data. Intensive care medicine has been closely integrated with data since its birth. Critical care research requires an integrative approach that embraces the complexity of critical illness and the computational technology and algorithms that can make it possible. Considering the need of standardization of application of big data in intensive care, Intensive Care Medicine Branch of China Health Information and Health Care Big Data Society, Standard Committee has convened expert group, secretary group and the external audit expert group to formulate Chinese Experts' Consensus on the Application of Intensive Care Big Data (2022). This consensus makes 29 recommendations on the following five parts: Concept of intensive care big data, Important scientific issues, Standards and principles of database, Methodology in solving big data problems, Clinical application and safety consideration of intensive care big data. The consensus group believes this consensus is the starting step of application big data in the field of intensive care. More explorations and big data based retrospective research should be carried out in order to enhance safety and reliability of big data based models of critical care field.

Ferroptosis: A new therapeutic target for bladder cancer.

Bladder cancer (BC) is the most frequent type of urinary system cancer. The prognosis of BC is poor due to high metastasis rates and multidrug resistance. Hence, development of novel therapies targeting BC cell death is urgently needed. As a novel cell death type with strong antitumor potential, ferroptosis has been investigated by many groups for its potential in BC treatment. As an iron-dependent cell death process, ferroptosis is characterized by excessive oxidative phospholipids. The molecular mechanisms of ferroptosis include iron overload and the system Xc-GSH-GPX4 signaling pathway. A recent study revealed that ferroptosis is involved in the metastasis, treatment, and prognosis of BC. Herein, in this review, we comprehensively summarize the mechanism of ferroptosis, address newly identified targets involved in ferroptosis, and discuss the potential of new clinical therapies targeting ferroptosis in BC.

Melatonin: A window into the organ-protective effects of sepsis.

Sepsis is an uncontrolled host response to infection. In some cases, it progresses to multi-organ insufficiency, leading to septic shock and increased risk of mortality. Various organ support strategies are currently applied clinically, but they are still inadequate in terms of reducing mortality. Melatonin is a hormone that regulates sleep and wakefulness, and it is associated with a reduced risk of death in patients with sepsis. Evidence suggests that melatonin may help protect organ function from sepsis-related damage. Here, we review information related to the role of melatonin in protecting organ function during sepsis and explore its potential clinical applications, with the aim of providing an effective therapeutic strategy for treating sepsis-induced organ insufficiency.

Comparison of COVID-19 Induced Respiratory Failure and Typical ARDS: Similarities and Differences.

Coronavirus disease 2019 (COVID-19) is a predominantly respiratory infectious disease caused by novel coronavirus infection (SARS-CoV-2), respiratory failure is the main clinical manifestation and the leading cause of death. Even though it can meet the acute respiratory distress syndrome (ARDS) Berlin definition, only some clinical features of COVID-19 are consistent with typical ARDS, and which has its own peculiar phenotypes. When compared with typical ARDS, in addition to the typical diffuse alveolar injury, COVID-19 has unique pathological and pathophysiological features, such as endothelial injury, extensive microthrombus, and pulmonary capillary hyperplasia. The clinical features of patients with respiratory failure caused by COVID-19 are heterogeneous and can be generally divided into two phenotypes: progressive respiratory distress and unique "silent hypoxemia". The "H-type" characteristics of reduced lung volume, decreased lung compliance, and unmatched ventilator-perfusion ratio. While some patients may have close to normal lung compliance, that is "L-type". Identifying the exact phenotype in whom are suffered with COVID-19 is crucial to guide clinicians to adopt appropriate treatment strategies. This review discussed the similarities and differences in the pathogenesis, pathophysiology, clinical features and treatment strategies of COVID-19 induced acute respiratory failure and typical ARDS.

Application of glucagon-like peptide-1 receptor antagonists in fibrotic diseases.

Fibrosis can occur in various organs, leading to structural destruction, dysfunction, and even organ failure. Hence, organ fibrosis is being actively researched worldwide. Glucagon-like peptide-1 (GLP-1), a naturally occurring hormone, binds to a G-protein-coupled receptor widely distributed in the pancreas, kidney, lung, heart, gastrointestinal tract, and other organs. Synthetic GLP-1 analogs can be used as GLP-1 receptor agonists (GLP-1RAs) for treating diabetes mellitus. In recent years, GLP-1RAs have also been found to exert anti-inflammatory, antioxidant, and cardiovascular protective effects. GLP-1RAs have also been shown to inhibit fibrosis of solid organs, such as the lung, heart, liver, and kidney. In this review, we discuss the advancements in research on the role of GLP-1RAs in the fibrosis of the heart, lung, liver, kidney, and other organs to obtain new clues for treating organ fibrosis.

Peripherally inserted central catheters have a protective role and the effect of fluctuation curve feature in the risk of bloodstream infection compared with central venous catheters: a propensity-adjusted analysis.

BACKGROUND: The prevention of peripherally inserted central catheters (PICC)-associated BSI and central venous catheters (CVC)-associated BSI have been a topic of national importance in China. Therefore, we aimed to explore the epidemiological characteristics of central line-associated bloodstream infection (CLABSI), and to evaluate whether PICCs were associated with a protective effect for CLABSI. METHODS: A retrospective cohort study was conducted in teaching hospital in Western China. All adult patients received a CVC or PICC during their hospital stay were included from January 2017 to December 2020. Primary endpoint was CLABSI up to 30 days after CVC or PICC placement. Propensity scores with a 2:1 match was used to account for potential confounders, and restricted cubic spline was used to visualize the risk of CLABSI at different time points during the catheterization. RESULTS: A total of 224687 devices (180522 PICCs and 45965 CVCs) in 24879 patients were included. The overall incidence was 1.8 CLABSIs per 1000 catheter-days. The odds ratio (OR) value increased day by day after PICC insertion, reached a relatively high point on the 4th day, and decreased from days 5 through 8. From the 9th day of intubation the OR value began to gradually increase day by day again. After covariate adjustment using propensity scores, CVCs were associated with higher risk of CLABSI (adjHR = 3.27, 95% CI 2.38-4.49) compared with PICCs. CONCLUSIONS: PICCs have a protective role and the effect of fluctuation curve feature in CLABSI when compared to CVCs, and the first 8 calendar days after CVC insertion are the acute stage of CVC-associated BSI.

Resveratrol: Potential Application in Sepsis.

Sepsis is a life-threatening organ dysfunction syndrome caused by host response disorders due to infection or infectious factors and is a common complication of patients with clinical trauma, burns, and infection. Resveratrol is a natural polyphenol compound that is a SIRT-1 activator with anti-inflammatory, antiviral, antibacterial, antifungal inhibitory abilities as well as cardiovascular and anti-tumor protective effects. In recent years, some scholars have applied resveratrol in animal models of sepsis and found that it has an organ protective effect and can improve the survival time and reduce the mortality of animals with sepsis. In this study, Medline (Pubmed), embase, and other databases were searched to retrieve literature published in 2021 using the keywords "resveratrol" and "sepsis," and then the potential of resveratrol for the treatment of sepsis was reviewed and prospected to provide some basis for future clinical research.

Electrical Impedance Tomography Predicts Weaning Success in Adult Patients With Delayed Upper Abdominal Surgery: A Single-Center Retrospective Study.

Objective: To evaluate the predictive value of electrical impedance tomography (EIT) in patients with delayed ventilator withdrawal after upper abdominal surgery. Methods: We retrospectively analyzed data of patients who were ventilated >24 h after upper abdominal surgery between January 2018 and August 2019. The patients were divided into successful (group S) and failed (group F) weaning groups. EIT recordings were obtained at 0, 5, 15, and 30 min of spontaneous breathing trials (SBTs) with SBT at 0 min set as baseline. We assessed the change in delta end-expiratory lung impedance and tidal volume ratio (ΔEELI/VT) from baseline, the change in compliance change percentage variation (|Δ(CW-CL)|) from baseline, the standard deviation of regional ventilation delay index (RVDSD), and global inhomogeneity (GI) using generalized estimation equation analyses. Receiver operating characteristic curve analyses were performed to evaluate the predictive value of parameters indicating weaning success. Results: Among the 32 included patients, ventilation weaning was successful in 23 patients but failed in nine. Generalized estimation equation analysis showed that compared with group F, the ΔEELI/VT was lower, and the GI, RVDSD, and (|Δ(CW-CL)|) were higher in group S. For predicting withdrawal failure, the areas under the curve of the ΔEELI/VT, (|Δ(CW-CL)|), and the RVDSD were 0.819, 0.918, and 0.918, and 0.816, 0.884, and 0.918 at 15 and 30 min during the SBTs, respectively. Conclusion: The electrical impedance tomography may predict the success rate of ventilator weaning in patients with delayed ventilator withdrawal after upper abdominal surgery.

Hydrogen: Potential Applications in Solid Organ Transplantation.

Ischemia reperfusion injury (IRI) in organ transplantation has always been an important hotspot in organ protection. Hydrogen, as an antioxidant, has been shown to have anti-inflammatory, antioxidant, and antiapoptotic effects. In this paper, the protective effect of hydrogen against IRI in organ transplantation has been reviewed to provide clues for future clinical studies.

The application of a structural nutritional care management model in severe acute pancreatitis patients undergoing early enteral nutrition via nasal jejunal nutrition tubes.

OBJECTIVE: To investigate the advantages of a structural nutritional care management model (hereafter referred to as structural management) in severe acute pancreatitis (SAP) patients undergoing early enteral nutrition via nasal jejunal nutrition tubes. METHODS: A total of 88 patients with SAP diagnosed and treated in our hospital were recruited as the study cohort and underwent enteral nutrition treatment. A random number table was used for the random grouping. The control group was routinely managed, and the study group was also administered structural management. In the study, we observed and compared the differences and changes in the relevant nutritional indexes (albumin (ALB), prealbumin (PA), and transferrin (TRF)) and the gastrointestinal hormone indexes (gastrin (MTL), vasoactive peptide (VIP), and 5-hydroxytryptamine (5-HT)) before and after the treatment. Between the two groups, we also compared the times required for the recovery of the relevant gastrointestinal physiological function indexes, the mechanical ventilation times, the hospitalization durations in the ICU, the complications, the satisfaction indexes and the satisfaction rates. RESULTS: After the treatment, the relevant nutritional indicators, including ALB (35.26±3.35 g/L), PA (25.19±5.64 g/L), and TRF (2.82±0.54 g/L) in the study group were higher than the ALB (28.19±2.74 g/L), PA (21.29±4.32 g/L), and TRF (2.26±0.32 g/L) in the control group (all P<0.05). After the treatment, the relevant gastrointestinal hormone indicators, including MTL (269.72±37.18 pg/mL) and 5-HT (2214.61±432.95 ng/mL) in the study group were higher than the MTL (231.25±32.63 pg/mL) and 5-HT (1914.26±391.53 ng/mL) in the control group (all P<0.05). Moreover, the VIP in the study group was 53.13±6.17 pg/mL, which was significantly lower than the VIP in the control group (65.29±9.35 pg/mL, P<0.05). The time required for the recovery of the gastrointestinal function indexes in the study group was less than it was in the control group (P<0.05). The duration of the mechanical ventilation (8.16±1.93 days) and the hospitalization durations in the ICU (9.24±0.77 days) in the study group were significantly shorter than the duration of the mechanical ventilation (12.24±1.65 days) and the hospitalization durations in the ICU (13.23±0.88 days) in the control group (all P<0.05). The overall complication rate in the study group was significantly lower than it was in the control group (P<0.05), and the satisfaction rate in the study group was significantly higher than it was in the control group (P<0.05). CONCLUSION: The combined use of structural management in SAP patients undergoing enteral nutrition treatment significantly improved the relevant nutritional indicator and gastrointestinal hormone indicator levels. It also contributed to the recovery of the gastrointestinal function indicators in the SAP patients, reduced the durations of their mechanical ventilation, their hospitalization durations in the ICU, and their complications and contributed to a significant increase in their satisfaction with the nursing.

GLP-1 Receptor: A New Target for Sepsis.

Patients with sepsis often exhibit hyperglycemia, which increases mortality. glucagon-like peptide-1 receptor agonists (GLP-1RAs) not only regulate blood glucose homeostasis but also improve organ dysfunction, regulate immunity, and control inflammation and other functions in patients with sepsis. Here, we review the possible application of GLP-1RAs in sepsis, to provide a new perspective for the clinical diagnosis and treatment of patients with sepsis complicated with stress hyperglycemia.

Neutrophil : lymphocyte ratio is associated with disease severity and mortality in patients with Stevens-Johnson syndrome/toxic epidermal necrolysis.

The neutrophil : lymphocyte ratio (NLR), platelet : lymphocyte ratio (PLR), C-reactive protein : albumin ratio (CAR), and albumin : fibrinogen ratio (AFR) have been considered as useful inflammatory biomarkers. However, their roles in Stevens-Johnson Syndrome (SJS)/toxic epidermal necrolysis (TEN) still remain unclear. This study aimed to test whether NLR, PLR, CAR, and AFR serve as predictive markers of disease severity and systemic inflammation in patients with SJS/TEN. This retrospective study included 40 patients with SJS/TEN and 60 healthy controls. The correlation between these markers and severity-of-illness score for toxic epidermal necrolysis (SCORTEN), ABCD-10, procalcitonin (PCT), C-reactive protein (CRP) were analyzed and compared. Univariable and multivariable analysis were used to assess associations of variables with mortality. The receiver-operator curves (ROC) were used to evaluate the predictive value of variables for mortality in SJS/TEN patients. The results demonstrated that the NLR and PLR of SJS/TEN patients were significantly higher and the AFR was significantly lower when compared with healthy controls (p < 0.05). The NLR and CAR were positively correlated with SCORTEN, ABCD-10, PCT, and CRP. The NLR in SCORTEN of ≥3 group was significantly higher than that in SCORTEN <3 group (p < 0.05) and there were no significant differences between PLR, CAR, and AFR between the two groups. The univariate analysis suggested that NLR of >5.79 was a risk factor for mortality (odds ratio, 10.5; p < 0.05), but the association was no longer statistically significant in multivariable analysis. The ROC showed that NLR had a sensitivity of 85.7% and specificity of 63.6% for predicting death with a cut-off value of 5.79 (p < 0.05) in SJS/TEN patients. In conclusion, among the four markers, NLR and CAR can partially reflect severity and inflammatory status in patients with SJS/TEN. NLR was also a predictor of death.

Clinical Symptoms and Outcomes of Severe Pneumonia Caused by Chlamydia psittaci in Southwest China.

Here, we aimed to retrospectively analyze the clinical characteristics of 27 patients with severe pneumonia caused by Chlamydia psittaci between January 2019 and April 2021 in southwest China. To this end, we collected data on the exposure history, clinical symptoms, laboratory examination, imaging characteristics, evolution, etiology, treatment, and outcomes to suggest a better diagnosis and prevention system. Our results showed that a metagenomic next-generation sequencing test could provide early diagnosis. All patients were sensitive to quinolones and tetracyclines, and the recovery rate was relatively high. Overall, all patients were in critical condition with moderate to severe acute respiratory distress syndrome and shock. In conclusion, early diagnosis of pneumonia caused by C. psittaci depends on effective molecular testing, and most patients recover after treatment.

SIRT4 suppresses the inflammatory response and oxidative stress in osteoarthritis.

Sirtuins have been involved in the osteoarthritis (OA) process. However, the functions of SIRT4 in the degeneration of human chondrocytes and OA are not fully understood. This study aimed to explore the role of SIRT4 during OA and mechanisms implicated. We extracted total protein and mRNA of the cartilage from OA patients and isolated the chondrocytes from the cartilage in different degenerated degrees for cell culture. Collagen II and SIRT4 levels of the tissues were analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) and Western blot. Chondrocytes were transferred with SIRT4-siRNA, treated with recombinant human SIRT4 protein for 24 h, respectively. Aggrecan, collagen I, collagen II, MMP-13, IL-6, TNF-α, SOD1, SOD2, and CAT expression, and ROS levels were investigated by Western blot, RT-PCR, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), or flow cytometry. Collagen II decreased significantly in severely degenerated cartilage compared to the mild one, paralleling with SIRT4 expression both in protein and mRNA levels. Chondrocytes in severe OA grade were observed with a decrease in aggrecan, collagen II, SOD1, SOD2, CAT expression, nonetheless, an increase in collagen I, reactive oxygen species (ROS), MMP-13, IL-6, and TNF-α levels. However, SRIT4 protein treatment significantly upregulated aggrecan, collagen II, an antioxidant enzyme, and suppressed ROS and inflammatory response. Further analysis revealed that silencing of SIRT4 expression induced healthy chondrocytes, a decrease in aggrecan, collagen II and antioxidant enzyme expression, and an increase in ROS and inflammatory response, importantly, which can be reversed by SIRT4 protein stimuli. Our results elucidated that SIRT4 was tangled with the development of OA, and SIRT4 overexpression contributes to suppresses the inflammatory response and oxidative stress.

Dexmedetomidine for prevention of propofol injection pain upon induction of anesthesia: a meta-analysis.

PURPOSE: Propofol injection pain is a very common problem during the induction of general anesthesia. The purpose of this review is to evaluate the effectiveness of dexmedetomidine for the prevention of propofol injection pain so as to provide evidence for future clinical applications. METHODS: PubMed, Embase, Cochrane library, and Google Scholar databases were searched for relevant randomized controlled trials examining the use of dexmedetomidine for the prevention of propofol injection pain. The pooled risk ratio (RR) with corresponding 95% confidence intervals (CI) was calculated employing fixed-effects or random-effects models, depending upon the heterogeneity of the included trials. Because of the wide variety of interventions investigated, three comparisons of studies were established, dexmedetomidine compared with saline, lidocaine, and ketamine. RESULTS: Compared with saline, dexmedetomidine allowed more patients to experience no pain upon propofol injection (RR = 0.26, 95% CI (0.18, 0.38), P < 0.00001). Dexmedetomidine at doses of < 1 µg/kg did not show superiority in relieving propofol injecting pain compared with lidocaine (RR = 1.28, 95% CI (0.82, 2.00), P = 0.04). Dexmedetomidine is less effective than ketamine in reducing pain on propofol injection with a statistically significant P value of < 0.000010 (RR = 1.93, 95% CI (1.51, 2.47)). The report of adverse effects is rare, dexmedetomidine is a safe method to reduce propofol injection pain. CONCLUSION: Pretreatment with dexmedetomidine may be a useful alternative for reducing pain on propofol injection, even though dexmedetomidine is less effective than lidocaine and ketamine.