Caudal block is easily performed because the landmarks are superficial. However, the sacral hiatus is small and shallow in pediatric patients. In the present study, we evaluated under general anesthesia whether the distance between the bilateral superolateral sacral crests increased with growth, whether an equilateral triangle was formed between the apex of the sacral hiatus and the bilateral superolateral sacral crests, and whether expansion of the epidural space could be confirmed by ultrasound. This prospective observational study included 282 children who were ASA I–II. Under general anesthesia, each patient was placed in the lateral bent knees position, and the attending anesthesiologist drew an equilateral triangle and measured the distance between the bilateral superolateral sacral crests along a line forming the base of the triangle. Then the sacral hiatus was identified by ultrasound. Differences of the distance between the anatomical landmarks measured by the anesthetist and by ultrasound were evaluated. Two patients were excluded because the superolateral sacral crests and sacral hiatus could not be palpated. The base of the triangle increased in proportion to age up to 10 years old, with a significant correlation between age and the length of the base (Spearman’s r value = 0.97). The triangle was not an equilateral triangle under 7 years old. The sacral hiatus could be identified by ultrasound and we could confirm expansion of the epidural space in all patients. We observed a correlation between age and the length of the triangle base in children under 10 years old. Although detection of the anatomical landmarks by palpation differed from identification by ultrasound in pediatric patients, performing ultrasound is important. Epinephrine should be added to the anesthetic to avoid complications. Current Controlled Trials UMIN000017898 . Registered 14 June 2015. Date of protocol fixation was 1st December, 2008 and Anticipated trial start date was 5th January, 2009.

I-gel is a noncuff type of laryngeal airway mask. No horizontal line has yet been determined as an ideal position for pediatric sizes because of the variability in length of the oropharyngeal–laryngeal arch in children. We investigated whether there is a correlation between insertion length and patient body weight or height for the pediatric I-gel sizes from 1.5 to 2.5. With parental informed consent, we planned to maintain the airway of 130 children aged from 7 months to 13 years by using the I-gel device under general anesthesia. The following two parameters were evaluated: (1) distance between the teeth and the connector wing; (2) insertion length (distance from the distal end of the gastric tube to the teeth). Size selection was determined on the basis of patients’ body weight. We identified the relationship between each parameter and height or weight. Average insertion length became gradually longer with increasing height and weight. Spearman’s R between insertion length and height or weight was 0.8. There was more correlation with height than with weight in pediatric size 2.5. Results suggested that it is possible to draw an ideal line on the I-gel with sizes 1.5 and 2 only.

Background: Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited disorder characterized by extreme epithelial fragility and progressive cicatrization, frequently leading to severe ocular surface disease and early visual impairment. Surgical interventions such as ocular surface reconstruction (OSR) in childhood are often delayed because of anesthetic risks and concerns regarding recurrence. Consequently, the effectiveness of OSR, including amniotic membrane transplantation (AMT), and its impact on visual development remain poorly documented. Methods: We report a case series of two pediatric patients (three eyes) with genetically confirmed RDEB who underwent single-step OSR using AMT. Clinical outcomes, long-term visual acuity, perioperative management, and histopathological findings were evaluated. Results: Ocular manifestations included corneal epithelial damage, symblepharon, and pseudopterygium extending over the cornea. One patient underwent symblepharon lysis, superficial keratectomy, and AMT onto the bare sclera in the right eye at age 4 and in the left eye at age 8, both under intubated general anesthesia. The other patient underwent the same procedure in the right eye at age 6. Best spectacle-corrected visual acuity improved from ≤20/300 to 20/30 in all eyes, and pupillary zone clarity was maintained during the follow-up period (up to 6 years). Histopathology confirmed pseudopterygium with squamous metaplasia, goblet cell loss, and fibrovascular stroma. Safe general anesthesia was achieved through meticulous multidisciplinary perioperative planning involving anesthesiologists, dermatologists, and pediatricians. No systemic complications related to anesthesia or perioperative management were observed. Conclusions: Single-step OSR with on-lay AMT can restore and preserve visual function in pediatric RDEB. Early surgical intervention may prevent profound amblyopia and provide durable ocular surface stability. A multidisciplinary approach enables safe general anesthesia and perioperative management.

Backgrounds: Hypoxemia develops more quickly in children than in adults due to their high oxygen consumption relative to their body weight and small functional residual capacity. Therefore, cricothyroid puncture must be performed promptly in cannot-intubate and cannot-ventilate situations. However, the success rate of cricothyroid puncture in children is <1%. We hypothesized that the low success rate of cricothyroid puncture in children may be related to the cricothyroid membrane's hypermobility. The aim of the present study was to measure the deviation of the cricothyroid membrane from the midline when applying compressive pressure.Methods: After obtaining institutional ethics committee approval, written informed consent was obtained from the patients’ parents. Children aged from 1 month to 15 years who had undergone scheduled operations under general anesthesia and with an American Society of Anesthesiologists Physical Status Classification grade of 1 or 2 were enrolled in this study. The patients were divided into the following four different age groups: 1 month–1 year, 2–4 years, 5–10 years, and 11–15 years. After the intravenous injection of fentanyl, propofol, and rocuronium, the airway was identified using a linear hockey stick ultrasound probe. The cricothyroid membrane was compressed with a force of 5 newtons (N), and cricothyroid membrane deflection was recorded. The primary outcome was the cricothyroid membrane deviation from the midline relative to the tracheal diameter.Results: Twenty patients were enrolled in this study. No adverse events were noted. The mean cricothyroid membrane deviations from the midline divided by the tracheal diameter was 0.16 ± 0.09, 0.05 ± 0.04, 0.04 ± 0.04, and 0.02 ± 0.03 in children aged 1 month–1 year, 2–4 years, 5–10 years, and 11–15 years, respectively.Conclusion: The cricothyroid membrane deviation due to the application of a compressive force to the overlying skin tended to be larger in younger patients.