A novel approach to calculate the required volume of air for bronchial blockers in young children.

INTRODUCTION: Bronchial blocker balloons inflated with small volumes of air increase balloon pressure, involving a risk of airway injury especially in young children. However, there are no established guidelines regarding the appropriate volumes of air required to provide safe bronchial occlusion. METHODS: This study aimed to introduce a novel method for calculating the amount of air required for safe bronchial blocker balloon occlusion for one lung anesthesia in young children. We included 79 pediatric patients who underwent video-assisted thoracoscopic surgery at our hospital. Preoperatively, the balloon pressure and corresponding diameter of 5F bronchial blockers inflated with different volumes of air were measured. Intraoperatively, bronchial diameters measured by computerized tomographic scans were matched to the ex vivo measured balloon diameters. The quality of lung isolation, incidence of balloon repositioning, and airway injury were documented. Postoperatively, airway injury was evaluated through fiberoptic bronchoscopy. RESULTS: Balloon pressure and balloon diameter showed linear and nonlinear correlations with volume, respectively. The median lengths of the right and left mainstem bronchi were median (interquartile range) range: 5.3 mm (4.5-6.3) 2.7-8.15 and 21.8 (19.6-23.4) 14-29, respectively. Occluding the left mainstem bronchus required <1 mL of air, with a balloon pressure of 27 cm H2O. The isolation quality was high with no case of mucosal injury or displacement. Occluding the right mainstem bronchus required a median air volume of 1.3 mL, with a median balloon pressure of 44 cm H2O. One patient had poor lung isolation due to a tracheal bronchus and another developed mild and transient airway injury. CONCLUSION: The bronchial blocker cuff should be regarded as a high-pressure balloon. We introduced a new concept for safe bronchial blocker balloon occlusion for one-lung ventilation in small children.

Effects of positive end-expiratory pressure/recruitment manoeuvres compared with zero end-expiratory pressure on atelectasis in children: A randomised clinical trial.

BACKGROUND: Atelectasis is a common postoperative complication. Peri-operative lung protection can reduce atelectasis; however, it is not clear whether this persists into the postoperative period. OBJECTIVE: To evaluate to what extent lung-protective ventilation reduces peri-operative atelectasis in children undergoing nonabdominal surgery. DESIGN: Randomised, controlled, double-blind study. SETTING: Single tertiary hospital, 25 July 2019 to 18 January 2020. PATIENTS: A total of 60 patients aged 1 to 6 years, American Society of Anesthesiologists physical status 1 or 2, planned for nonabdominal surgery under general anaesthesia (≤2 h) with mechanical ventilation. INTERVENTIONS: The patients were assigned randomly into either the lung-protective or zero end-expiratory pressure with no recruitment manoeuvres (control) group. Lung protection entailed 5 cmH2O positive end-expiratory pressure and recruitment manoeuvres every 30 min. Both groups received volume-controlled ventilation with a tidal volume of 6 ml kg-1 body weight. Lung ultrasound was conducted before anaesthesia induction, immediately after induction, surgery and tracheal extubation, and 15 min, 3 h, 12 h and 24 h after extubation. MAIN OUTCOME MEASURES: The difference in lung ultrasound score between groups at each interval. A higher score indicates worse lung aeration. RESULTS: Patients in the lung-protective group exhibited lower median [IQR] ultrasound scores compared with the control group immediately after surgery, 4 [4 to 5] vs. 8 [4 to 6], (95% confidence interval for the difference between group values -4 to -4, Z = -6.324) and after extubation 3 [3 to 4] vs. 4 [4 to 4], 95% CI -1 to 0, Z = -3.161. This did not persist from 15 min after extubation onwards. Lung aeration returned to normal in both groups 3 h after extubation. CONCLUSIONS: The reduced atelectasis provided by lung-protective ventilation does not persist from 15 min after extubation onwards. Further studies are needed to determine if it yields better results in other types of surgery. TRIAL REGISTRATION: Chictr.org.cn (ChiCTR2000033469).

Analgesic efficacy and impact of caudal block on surgical complications of hypospadias repair: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: is commonly used for children undergoing hypospadias repair. However, the safety of caudal block for hypospadias repair in children is controversial in terms of surgical complications such as urethrocutaneous fistula and glans dehiscence. We sought to perform a meta-analysis to estimate the analgesic efficacy and relative complications of caudal block for hypospadias repair in children. METHODS: We identified comparative studies of caudal block versus peripheral nerve block or no caudal block; studies were published or presented through 1 January 2018, and reports of analgesic efficacy or surgical complications of hypospadias repair in children were identified. Peripheral nerve block includes dorsal nerve penile block and pudendal nerve block. Data were abstracted from studies comparing caudal block with peripheral nerve block or no caudal block; original source data were used when available. We prespecified separate assessments of randomized controlled trials (RCTs) and observational studies given the inherent differences between types of study designs. Data from 298 patients in four RCTs and from 1726 patients in seven observational studies were included. RCT and observational data were analyzed separately. RESULTS: In RCTs, caudal blocks (compared with peripheral nerve blocks) showed no detectable differences in terms of need for additional analgesia within 24 hours after the surgery (OR 10.49; 95% CI 0.32 to 343.24; p=0.19), but limited data showed lower pain scores 24 hours after the surgery (standardized mean difference (SMD) 1.57; 95% CI 0.29 to 2.84; p=0.02), a significantly shorter duration of analgesia (SMD -3.33; 95% CI -4.18 to -2.48; p<0.0001) and analgesics consumption. No significant differences were observed in terms of postoperative nausea and vomiting (OR 3.08; 95% CI 0.12 to 77.80; p=0.50) or motor weakness (OR 0.01; 95% CI -0.03 to 0.05; p=0.56). Only one randomized study showed that caudal blocks (compared with peripheral nerve blocks) were associated with detectable differences in urethrocutaneous fistula rate (OR 25.27; 95% CI 1.37 to 465.01; p=0.03) and parental satisfaction rate (OR 0.07; 95% CI 0.02 to 0.21; p<0.00001). In observational studies, caudal block was not associated with surgical complications in all types of primary hypospadias repair (OR 1.83; 95% CI 0.80 to 4.16; p=0.15). To adjust for confounding factors and to eliminate potential selection bias involving caudal block indication, we performed subgroup analysis including only patients with distal hypospadias. This analysis revealed similar complication rates in children who received a caudal block and in children not receiving caudal block (OR 1.02; 95% CI, 0.39 to 2.65; p=0.96). This result further confirmed that caudal block was not a risk factor for surgical complications in hypospadias repair. The direction of outcomes in all the other subgroup analyses did not change, suggesting stability of our results. CONCLUSIONS: In RCTs, only limited data showed peripheral nerve blocks providing better analgesic quality compared with caudal blocks. In real-world non-randomized observational studies with greater number of patients (but with admitted the potential for a presence of selection bias and residual confounders), caudal blocks were not associated with postoperative complications including urethrocutaneous fistula and glans dehiscence.

MiR-29 Targets PUMA to Suppress Oxygen and Glucose Deprivation/Reperfusion (OGD/R)-induced Cell Death in Hippocampal Neurons.

INTRODUCTION: We previously demonstrated that microRNAs (miRNA) play an important role in Hypothermic Circulatory Arrest (DHCA)-associated neural injury. However, the specific role of miRNAs in the pathogenesis of DHCA-induced neuron death is still unclear. MATERIAL AND METHODS: Thus, in the present study, we investigated miR-29 expression and roles in neuronal HT-22 cells with Oxygen-glucose Deprivation/reoxygenation (OGD/R). In this study, the model of OGD/R was established using an airtight culture container and the anaeropack. Measurement of Reactive Oxygen Species (ROS) production and Mitochondrial Membrane Potential (MMP) was done using the probes of JC-1 and H2DCFDA. The microRNA (miRNA) profile in hippocampal neurons from rat model of DHCA was determined by miRNA deep sequencing. RESULTS: We found that the expression of the miR-29 family (miR-29a/b/c) was significantly reduced in model of DHCA and OGD/R. Overexpression of the miR-29 family inhibited the OGD/R-induced elevation of ROS and reduction of MMP in HT-22 cells. In addition, administration of the miR-29 family suppressed proteins of Keap1, Bax and PUMA and increased Nrf2 expression. We further demonstrated that the miR-29 family targeted the PUMA by luciferase reporter assay and Western blot analysis. CONCLUSION: In conclusion, our data suggest that by targeting a pro-apoptotic BCL2 family member PUMA, the miR-29 family might emerge as a strategy for protection against DHCA-mediated neural cell injury.

Caudal and intravenous dexamethasone as an adjuvant to pediatric caudal block: A systematic review and meta-analysis.

BACKGROUND: Dexamethasone has become a popular additive for regional anesthesia. The aim of this meta-analysis was to assess the effectiveness of this additive on the duration of postoperative analgesia, postoperative vomiting, and possible adverse events in pediatrics. METHODS: We searched databases, conference records, and registered trials for randomized controlled trials. The databases included the Cochrane Library, JBI Database of Systematic Reviews, PubMed, ISI Web of Knowledge, Science-Direct, and Embase. Odds ratio, weighted mean difference, and the corresponding 95% confidence intervals were calculated using the REVMAN software, version 5.3, for data synthesis and statistical analysis, which following the PRISMA statement. The main outcomes were duration of postoperative analgesia (time from the end of surgery to first administration of analgesics as evidenced by a pain score) and postoperative vomiting. RESULTS: Seven studies were selected for this meta-analysis, involving 647 pediatric patients. All the patients were randomized to receive caudal or intravenous dexamethasone with caudal block (experimental group) or plain caudal block (control group). There was significantly longer duration of postoperative analgesia in the experimental group compared with control group (weighted mean difference: 238.40 minutes; 95% CI: 193.41-283.40; P < .00001). The experimental group had fewer patients who needed analgesics after surgery (odds ratio: 0.18 minutes; 95% CI: 0.05-0.66; P = .009). Additionally, the number of subjects who remained pain-free to 2, 6, 24, and 48 hours after operation was significantly greater in the experimental group than control group. Side effects in these 2 groups were comparable (odds ratio: 0.94; 95% CI: 0.34-2.56; P = .90). The incidence of postoperative vomiting was significantly decreased in the experimental group compared with control group (odds ratio: 0.29; 95% CI: 0.13-0.63; P = .002). CONCLUSION: Caudal and intravenous dexamethasone could provide longer duration of postoperative analgesia and reduced the incidence of postoperative vomiting with comparable adverse effects than plain caudal block. However, any additive to the caudal space carries with it the potential for neurotoxicity and that caution should always be exercised when weighting the risks and benefits of any additive. The result was influenced by small numbers of participants and significant heterogeneity.

[Adrenal function evaluation using ACTH stimulation test in children with sepsis and septic shock].

OBJECTIVE: Sepsis and septic shock remain a common problem that results in significant mortality and morbidity in pediatric intensive care units (PICU). According to literature, the use of more physiologic steroid replacement therapy is associated with hemodynamic and survival benefits in adult patients with relative adrenal insufficiency (RAI) and catecholamine-resistant septic shock. But little information is available in children. The aim of the current prospective study was to determine the prevalence of adrenal insufficiency in children with sepsis and septic shock using a low-dose adrenocorticotropic hormone (ACTH) stimulation test (1 microg/1.73 m2) in children. METHODS: The authors performed cortisol estimation at baseline and after low-dose (1 microg/1.73 m2) ACTH stimulation at 30 mins in children during the first 24 hours in patients with sepsis or septic shock admitted to our PICU. Adrenal insufficiency was defined as a response < or = 90 microg/L. Absolute adrenal insufficiency (AAI) was further defined as baseline cortisol (T0) < 200 microg/L and RAI insufficiency by T0 > or = 200 microg/L. RESULTS: Sixty-two consecutive cases with sepsis and septic shock admitted to PICU of Shanghai Jiaotong University Affiliated Children's Hospital from April, 2006 to March, 2007. The median age was 37.6 months (range, 2 - 168 months), and their gender distribution was 42 (67.7%) males and 20 (32.3%) females, 53 cases had sepsis (85.5%) and 9 had septic shock (14.5%). The mean pediatric critical illness score (PCIS) was 79.3 +/- 9.2 and median pediatric risk of mortality score (PRMSIII) 11.3 (5 - 19), respectively. Overall mortality of sepsis and septic shock was 27.42%. The evaluation of adrenal insufficiency was conducted as follows. (1) The mean cortisol levels at baseline (T0) and 30 mins after ACTH stimulation (T1) were (318.6 +/- 230.4) microg/L, (452.3 +/- 230.7) microg/L and (454.7 +/- 212.7) microg/L, (579.3 +/- 231.9) microg/L in patients with severe sepsis and septic shock group, respectively. There were no significant difference between the two groups (P > 0.05). (2) The proportion of patients with adrenal insufficiency in the study population was 40.3% as defined by a response < or = 90 microg/L post test. The proportion of patients with adrenal insufficiency in sepsis and septic shock were 39.6% and 44.4%, respectively (chi2) = 0.073, P > 0.05). (3) The serum T0 and T1 levels were (320.5 +/- 223.9) microg/L, (462.3 +/- 212.0) microg/L and (384.3 +/- 258.3) microg/L, (500.7 +/- 470.6) microg/L, respectively, and the proportion of patients with adrenal insufficiency were 37.8% and 47.1% in the survivors and the dead (P > 0.05). The levels of T0 and T1 were related to the PCIS (P < 0.05). The morbidity of adrenal insufficiency was not related to the PCIS, PRISMIII, and number of organ that developed functional insufficiency (P > 0.05). CONCLUSIONS: Adrenal insufficiency may occur in patients with sepsis and septic shock in children. ACTH stimulation test may be helpful to determine whether corticosteroid therapy has a survival benefit in patients with relative adrenal insufficiency. A low-dose ACTH stimulation test can be used to evaluate the adrenal function status of severe sepsis and septic shock in children.