Background Pediatric radial artery cannulation is challenging because of the small vessel size. Nitroglycerin is a potent vasodilator and facilitates radial artery cannulation by increasing the internal diameter and preventing the vasospasm in adult patients. The authors hypothesize that subcutaneous nitroglycerin injection will improve the success rate of pediatric radial artery cannulation. Methods This double-blind, randomized, controlled, single-center study enrolled pediatric patients (n = 113, age less than 2 yr) requiring radial artery cannulation during general anesthesia. The participants were randomized into the nitroglycerin group (n = 57) or control group (n = 56). After inducing general anesthesia, nitroglycerin solution (5 μg/kg in 0.5 ml), or normal saline (0.5 ml) was subcutaneously injected above the chosen radial artery over 10 s with ultrasound guidance. Three minutes later, the ultrasound-guided radial artery cannulation was performed. Radial artery diameter was measured before and after the subcutaneous injection and after cannulation. The primary outcome was the first-attempt successful cannulation rate. The secondary outcomes included the diameter of the radial artery and the overall complication rate including hematoma and vasospasm. Results A total of 113 children were included in the analysis. The nitroglycerin group had a higher first-attempt success rate than the control group (91.2% [52 of 57] vs. 66.1% [37 of 56]; P = 0.002; odds ratio, 5.3; 95% CI, 1.83 to 15.6; absolute risk reduction, –25.2%; 95% CI, –39.6 to –10.7%). Subcutaneous nitroglycerin injection increased the diameter of the radial artery greater than normal saline (25.0 ± 19.5% vs. 1.9 ± 13.1%; 95% CI of mean difference, 16.9 to 29.3%; P < 0.001). Overall complication rate was lower in the nitroglycerin group than in the control group (3.5% [2 of 57] vs. 31.2% [18 of 56]; P = 0.001; odds ratio, 0.077; 95% CI, 0.017 to 0.350; absolute risk reduction, 28.6%; 95% CI, 15.5 to 41.8%). Conclusions Subcutaneous nitroglycerin injection before radial artery cannulation improved the first-attempt success rate and reduced the overall complication rates in pediatric patients. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Background: Desaturation frequently occurs in infants after general anaesthesia in the prone position. We aimed to evaluate the effect of regular alveolar recruitment in preventing atelectasis in infants and children after general anaesthesia in the prone position. Methods: Children (<3 yr) undergoing general anaesthesia (>2 h) in the prone position were randomised to either receive regular alveolar recruitment or standardised care without recruitment. Ultrasound-guided alveolar recruitment was performed for both groups, and mechanical ventilation was started with a tidal volume of 6 ml kg À1 and PEEP of 7 cm H 2 O. During mechanical ventilation, the intervention (regular recruitment) group received alveolar recruitment once per hour. Lung ultrasound was performed after inducing anaesthesia and each position change. The primary outcome was the incidence of significant atelectasis (defined by consolidation score !2 in any region) before extubation, as evaluated by lung ultrasound undertaken by an investigator masked to trial allocation. Results: Seventy-three children (regular recruitment: 37; standardised care: 36) were included in the analysis. Before the hourly intervention, atelectasis was similar between children randomised to regular alveolar recruitment or standardised care in both supine (83.3%, both groups; P>0.99) and prone positions (88.9% vs 91.9%; P¼0.970). The incidence of atelectasis before extubation was lower in children receiving regular alveolar recruitment (8.1%), compared with 47.2% in children randomised to standardised care (absolute risk reduction: 39.1% [95% confidence interval: 20.6e57.6%); P<0.001). Conclusions: Regular alveolar recruitment reduced the incidence of atelectasis at the end of surgery in infants and children <3 yr undergoing general anaesthesia in the prone position. Clinical trial registration: NCT03486847.

BACKGROUND Ultrasound-guided alveolar recruitment, regardless of the technique, could be more effective because it facilitates real-time monitoring of the expansion of collapsed alveoli. OBJECTIVES To evaluate and compare the effects of an ultrasound-guided lung recruitment manoeuvre with those of a conventional recruitment manoeuvre on the occurrence of postoperative atelectasis and clinical outcomes in children. DESIGN A randomised controlled trial. SETTING Tertiary children's hospital. PATIENTS Children aged 6 years or less. INTERVENTION Children scheduled for simple, superficial procedures underwent lung ultrasound after tracheal intubation (T1), at the end of surgery (T2) and before discharge from the postanaesthesia care unit (T3). Following lung ultrasound evaluation at T1 and T2, the conventional recruitment manoeuvre with a maximal airway pressure of 30 cmH2O was performed in the control group, while an ultrasound-guided recruitment manoeuvre was performed in the ultrasound group. MAIN OUTCOME MEASURES The primary outcome was the incidence of significant atelectasis at T3. RESULTS The incidences of atelectasis at T3 were 20.9 and 11.6% in the control (n = 43) and ultrasound groups (n = 43), respectively (odds ratio [OR], 2.012; 95% confidence interval [CI], 0.614 to 6.594; P = 0.249). The lung ultrasound scores were better in the ultrasound group than in the control group at T2 and T3, and the incidence of postoperative desaturation was higher in the control group than in the ultrasound group (16.3 vs. 2.3%; OR, 0.12; 95% CI 0.01 to 1.04; P = 0.05). The median airway pressure required for full lung expansion in the ultrasound group was 35 cmH2O at T1 and T2. Other postoperative outcomes were similar between groups. CONCLUSION Ultrasound-guided lung recruitment may be more effective than the conventional procedure in terms of the prevention of intra-operative atelectasis and postoperative desaturation; however, its beneficial effects on postoperative atelectasis remain unclear. An inspiratory airway pressure of more than 30 cmH2O is required for full recruitment of alveoli in healthy children. CLINICAL TRIAL REGISTRY ClinicalTrials.gov (NCT03453762).

Intubation using an endotracheal tube with a tapered cuff reduced the incidence and severity of postoperative sore throat and the incidence of hoarseness after surgery when compared with an endotracheal tube with a cylindrical cuff.

Ultrasonography facilitates arterial catheterization compared to traditional palpation techniques, especially in small arteries. For successful catheterization without complications, practitioners should be familiar with the anatomic characteristics of the artery and ultrasound-guided techniques. There are two approaches for ultrasound-guided arterial catheterization: the short-axis view out-of-plane approach and the long-axis view in-plane approach. There are several modified techniques and tips to facilitate ultrasound-guided arterial catheterization. This review deals with the anatomy relevant to arterial catheterization, several methods to improve success rates, and decrease complications associated with arterial catheterization.

Background: Perioperative central venous catheters are required but may be associated with various complications. Aims:The purpose of our study was to assess the incidence and perioperative risk factors for catheter-related internal jugular vein thrombosis in pediatric surgical patients. Methods: This prospective observational study included children under 6 years of age who were scheduled to undergo central venous catheterization of the right internal jugular vein under general anesthesia. A central venous catheter was inserted under real-time ultrasound guidance. An investigator examined for thrombosis using ultrasonography at predetermined time points. The primary aim was the incidence of catheter-related thrombosis from insertion until the 5th day postoperatively or the removal of the central venous catheter. The secondary aim was the determination of the risk factors for thrombosis.Results: Eighty patients completed the study. Internal jugular vein thrombi were found in 31 patients (38.8%, 95% CI 28.0-49.4). On multiple logistic regression analyses, the number of insertion attempts was the only influencing factor for catheter-related thrombosis (p < .001). More than two insertion attempts increased the risk of thrombosis (odds ratio 5.6; 95% CI 1.7 -18.7, p = .004). Anesthesia time (p = .017; mean difference 166.4 min; 95% CI 55.7-277.1), intraoperative red blood cell transfusion (p = .001; median difference 21.1 ml kg −1 ; 95% CI 6.6-34.4), and intensive care unit stay (p = .001; median difference 100.0 h; 95% CI 48-311) differed between patients with transient thrombosis and those with thrombosis lasting for more than 3 days. Conclusion:Internal jugular vein thrombosis was frequently detected by ultrasound following central venous catheterization in pediatric surgical patients. Multiple insertion attempts may be associated with the incidence of thrombosis. The clinical relevance of thrombi detected via ultrasound surveillance has not been determined.

Sugammadex, a selective antagonist of steroidal non‐depolarizing neuromuscular blocking agents, has been used in children in limited circumstances. However, neither pharmacokinetics (PKs) nor recovery profile of sugammadex for intense neuromuscular blockade reversal in children have been reported. This prospective study aimed to obtain a PK model of sugammadex and evaluate its efficacy and safety for intense neuromuscular blockade reversal in children. Forty children (age, 2–17 years) who underwent surgery that required early neuromuscular blockade reversal were enrolled. After neuromuscular blockade with 1 mg∙kg−1 of rocuronium, sugammadex (2, 4, and 8 mg∙kg−1) or a conventional dose of neostigmine (0.03 mg∙kg−1) was administered randomly after confirmation of zero post‐tetanic count. The plasma concentrations of rocuronium and sugammadex were measured 2 min after rocuronium injection; immediately before, 2, 5, 15, 60, 120, 240, and 480 min after the study drug injection. Response to train‐of‐four stimulation was continuously recorded. Noncompartmental analysis and population PK modeling were performed. For pharmacodynamics, the recovery profile was measured. Three‐compartment PK model was established for sugammadex. The median (interquartile range [IQR]) time from injection of 8 mg∙kg−1 of sugammadex to recovery of T4/T1greater than or equal to 0.9 at train‐of‐four stimulation was 1.1 (IQR: 0.88–1.8) min. No adverse events related to sugammadex were observed. We present a PK analysis of sugammadex for rocuronium‐induced intense neuromuscular blockade reversal in children with its recovery profile. The time to recover T4/T1 greater than or equal to 0.9 at train‐of‐four stimulation with 8 mg∙kg−1 of sugammadex was less than 3 min and comparable to that in adults.

Background An optimal endotracheal tube curve can be a key factor in successful intubation using the GlideScope videolaryngoscope. Aims This study aimed to evaluate the effects of tube tip‐modified stylet curve on the intubation time in children. Methods Children aged 1‐5 years were randomly assigned to either the standard curve (group S, n = 60) or tip‐modified curve (group T, n = 60) groups. In group S, the endotracheal tube curve was similar to that in the GlideScope. In group T, a point approximately 1.5 cm from the tube tip was additionally angled to the left by 15°‐20°. The primary outcome was the total intubation time, and the secondary outcomes were incidence of successful intubation in the first attempt, number of additional manipulations of the stylet curve, and visual analog scale (VAS) score for the easiness of intubation. Results The mean total intubation time was significantly longer in group S than that in group T (13.9 [10.8] vs. 9.0 [3.4] sec, mean difference, 4.9 s; 95% confidence interval [CI], 2.0‐7.8; p = .001). All patients in group T were successfully intubated in the first attempt, whereas those in group S were not (100% vs. 93.3%, relative risk [RR], 0.11; 95% CI, 0.01‐2.02; p = .1376). Three patients in group S could be intubated after modifying the ETT curve similar to that in group T. Operators reported that tracheal intubation was easier in group T than in group S (median [interquartile range] for VAS; 1 [1‐2] vs. 2 [1‐3]; p < .001). Conclusions Having additional angle of the endotracheal tube tip to the left could be a useful technique to facilitate directing and advancing endotracheal tube into the vocal cords.