In-Kyung Song

Effects of an alveolar recruitment manoeuvre guided by lung ultrasound on anaesthesia-induced atelectasis in infants: a randomised, controlled trial

Atelectasis occurs in the majority of children undergoing general anaesthesia. Lung ultrasound has shown reliable sensitivity and specificity for diagnosing anaesthesia‐induced atelectasis. We assessed the effects of a recruitment manoeuvre on atelectasis using lung ultrasound in infants undergoing general anaesthesia. Forty infants, randomly allocated to either a recruitment manoeuvre group or a control group, received volume‐controlled ventilation with 5 cmH2O positive end‐expiratory pressure. Lung ultrasound examination was performed twice in each patient, the first a minute after starting mechanical ventilation of the lungs and the second at the end of surgery. Patients in the recruitment manoeuvre group received ultrasound‐guided recruitment manoeuvres after each lung ultrasound examination. The incidence of significant anaesthesia‐induced atelectasis at the second lung ultrasound examination was less in the recruitment manoeuvre group compared with the control group (25% vs. 80%; p = 0.001; odds ratio (OR) 0.083; 95% confidence interval (CI): 0.019–0.370). The median (IQR [range]) lung ultrasound scores for consolidation and B‐lines on the second examination were lower in the recruitment manoeuvre group compared with the control group; 6.0 (3.0–9.3 [0.0–14.0]) vs. 13.5 (11.0–16.5 [8.0–23.0]); p < 0.001 and 6.5 (3.0–12.0 [0.0–28.0]) vs. 15.0 (10.8–20.5 [7.0–28.0]); p < 0.001, respectively. The lung ultrasound scores for consolidation on the first and second examinations showed a negative correlation with age (r = −0.340, p = 0.008; r = −0.380, p = 0.003). We conclude that ultrasound‐guided recruitment manoeuvres with positive end‐expiratory pressure proved useful in reducing the incidence of anaesthesia‐induced atelectasis in infants, although 5 cmH2O positive end‐expiratory pressure alone was not sufficient to eliminate it. In addition, the younger the patient, the more susceptible they were to atelectasis.

Critical incidents, including cardiac arrest, associated with pediatric anesthesia at a tertiary teaching children's hospital.

Analysis of critical incidents provides valuable information to improve the quality and safety of patient care. This study identified and analyzed pediatric anesthesia‐related critical incidents including cardiac arrests in a tertiary teaching childrens hospital.

Ultrasound assessment of gastric volume in children after drinking carbohydrate-containing fluids

BACKGROUND Gastric ultrasound is a valid tool for non-invasive assessment of the nature and volume of gastric contents in adults and children. Perioperative fasting guidelines recommend oral carbohydrates up to 2 h before elective surgery. We evaluated gastric volume in children using ultrasound before and after drinking carbohydrate fluids before surgery. METHODS Paediatric patients younger than 18 yr old undergoing elective surgery were enrolled. Initial ultrasound assessment of gastric volume was performed after fasting for 8 h. Two hours before surgery, patients were given carbohydrate drinks: 15 ml kg(-1) for patients younger than 3 yr old and 10 ml kg(-1) for those more than 3 yr old. Before induction of general anaesthesia, the gastric volume was reassessed. Parental satisfaction scores (0=totally satisfied, 10=totally dissatisfied) and complications were recorded. RESULTS Of the 86 enrolled patients, 79 completed the study; three refused to ingest the requested volume, and surgery was delayed for more than 2 h in four patients. The mean (sd) of the initial and second ultrasound measurements were 2.09 (0.97) and 1.85 (0.94) cm(2), respectively (P=0.01; mean difference 0.24 cm(2), 95% confidence interval 0.06-0.43). The median (interquartile range) satisfaction score was 2.4 (0-6). Two instances of postoperative vomiting and one instance of postoperative nausea occurred. CONCLUSIONS Carbohydrate fluids ingested 2 h before surgery reduced the gastric volume and did not cause serious complications in paediatric patients. Parents were satisfied with the preoperative carbohydrate drink. Children may benefit from drinking carbohydrate fluids up to 2 h before elective surgery. CLINICAL TRIAL REGISTRATION cris.nih.go.kr (KCT0001546).

Prediction of fluid responsiveness using a non-invasive cardiac output monitor in children undergoing cardiac surgery

BACKGROUND This study evaluated the ability of a non-invasive cardiac output monitoring device (NICOM) to predict fluid responsiveness in paediatric patients undergoing cardiac surgery. METHODS Children aged <5 yr undergoing congenital heart surgery were included. Once the sternum had been closed after repair of the congenital heart defect, 10 ml kg(-1) colloid solution was administered for volume expansion. Transoesophageal echocardiography (TOE) was performed to measure stroke volume (SV) and respiratory variation in aortic blood flow peak velocity (ΔV(peak)) before and after volume expansion. Haemodynamic and NICOM variables, including SV(NICOM), stroke volume variance (SVV(NICOM)), cardiac index (CI(NICOM)), and percentage change in thoracic fluid content compared with baseline (TFCd0%), were also recorded. Patients in whom the stroke volume index (SVI), measured using TOE, increased by >15% were defined as fluid responders. RESULTS Twenty-nine patients were included (13 responders and 16 non-responders). Before volume expansion, only ΔV(peak) differed between groups (P=0.036). The SVV(NICOM), HR, and central venous pressure did not predict fluid responsiveness, but ΔV(peak) did. The CI(NICOM) was not correlated with CI(TOE) (r=0.107, P=0.43). Using Bland-Altman analysis, the mean bias between CI(TOE) and CI(NICOM) was 0.89 litre min(-1) m(-2), with a precision of 1.14 litre min(-1) m(-2). Trending ability of NICOM for SVI and CI was poor when TOE was a reference method. CONCLUSIONS The SVV(NICOM) did not predict fluid responsiveness in paediatric patients during cardiac surgery. In addition, there was no correlation between CI(TOE) and CI(NICOM). Fluid management guided by NICOM should be performed carefully. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov NCT01996956.

Randomized controlled trial on preemptive analgesia for acute postoperative pain management in children

Preemptive analgesia is an anti‐nociceptive treatment that starts before surgery and prevents the establishment of central sensitization. Whether preemptive analgesia is more effective than conventional regimens for managing postoperative pain remains controversial. This study evaluated the efficacy of intravenous preemptive analgesia for acute postoperative pain control in pediatric patients.

Short-axis/out-of-plane or long-axis/in-plane ultrasound-guided arterial cannulation in children: A randomised controlled trial.

BACKGROUND Even with ultrasound guidance, arterial cannulation in children can be challenging. OBJECTIVE To compare the short-axis/out-of-plane (SAX) with the long-axis/in-plane (LAX) technique for ultrasound-guided arterial cannulation in children. DESIGN A randomised controlled trial. SETTING A tertiary university hospital, from 5 January 2015 to 21 April 2015. PATIENTS 101 children, American Society of Anesthesiologists’ physical status 1 or 2 and younger than 5 years of age. INTERVENTIONS All were randomised into one of four groups according to age and ultrasound guidance technique: infants with SAX technique (n = 25), infants with LAX technique (n = 25), children with SAX technique (n = 25) and children with LAX technique (n = 26). Ultrasound-guided arterial cannulation was performed under general anaesthesia via the radial or posterior tibial artery, depending on individual position and operative field. MAIN OUTCOME MEASURES The primary outcome was the total time to successful cannulation. Secondary outcomes included diameter and depth of the artery, time variables (imaging time, time to first successful puncture and time between first successful puncture and cannulation), number of puncture attempts, success rates (first puncture and final cannulation), posterior wall puncture rate and complications. RESULTS Ultrasound-guided arterial cannulation was successful in 97 children (96.0%). There were no significant differences in the total time to successful cannulation between the two groups. Ultrasound imaging time was significantly longer in the LAX group than in the SAX group (46.5 ± 39.2 vs 16.0 ± 17.6 s; 95% confidence interval of mean difference, −42.7 to −18.3; P = 0.000). However, the posterior wall puncture rate was significantly higher in the SAX group than in the LAX group (95.7% vs 18.0%; P = 0.000; odds ratio 0.01; 95% confidence interval, 0.002 to 0.048). There were no statistically significant differences in other secondary outcomes. CONCLUSION Despite the longer imaging time with the LAX approach, there was no significant difference in the total time to successful cannulation between the two techniques. The posterior wall puncture rate was lower in the LAX group than in the SAX group. TRIAL REGISTRATION Clinicaltrials.gov (identifier: NCT02333786).

Posterior Tibial Artery as an Alternative to the Radial Artery for Arterial Cannulation Site in Small Children: A Randomized Controlled Study

Background: We evaluated the posterior tibial artery as an alternative arterial cannulation site to the radial artery in small children. Methods: A two-stage study was conducted. First, we evaluated the anatomical characteristics of the posterior tibial artery compared with the radial and dorsalis pedis arteries. Next, a parallel-arm single-blind randomized controlled study compared the initial success rate of ultrasound-guided arterial cannulation among three arteries as a primary outcome. Results: Sixty patients were analyzed in the observational study. The diameter of the posterior tibial artery (1.5 ± 0.2 mm) was similar to that of the radial artery (1.5 ± 0.2 mm) and larger than that of the dorsalis pedis artery (1.2 ± 0.2 mm; P < 0.001). The posterior tibial artery has a larger cross-sectional area (2.8 ± 1.1 mm2) compared with the radial (2.3 ± 0.8 mm2; P = 0.013) and dorsalis pedis arteries (1.9 ± 0.6 mm2; P = 0.001). In total, 234 patients were analyzed in the randomized study. The first-attempt success rate of the posterior tibial artery (75%) was similar to that of the radial (83%; P = 0.129; odds ratio, 1.53; 95% CI, 0.69 to 3.37) and higher than that of the dorsalis pedis artery (45%; P < 0.001; odds ratio, 3.95; 95% CI, 1.99 to 7.87). Median cannulation time of the posterior tibial artery (21 s; interquartile range, 14 to 30) was similar to that of the radial artery (27 s; interquartile range, 17 to 37) and shorter than that of the dorsalis pedis artery (34 s; interquartile range, 21 to 50). Conclusions: The posterior tibial artery is a reasonable alternative to the radial artery for ultrasound-guided arterial cannulation in small children.

Optimal Chest Compression Position for Patients With a Single Ventricle During Cardiopulmonary Resuscitation.

Objectives: Few studies have examined cardiopulmonary resuscitation for patients with congenital heart disease, although they are at a high risk of cardiac arrest. Therefore, this study investigated the optimal chest compression position in patients with a single ventricle while providing them with basic life support. Design: This is a retrospective study of patients with a single ventricle who are undergoing chest CT. Setting: Tertiary teaching children’s hospital. Patients: A total of 185 patients with a single ventricle, including 73 patients before a bidirectional cavopulmonary shunt, 61 patients after a bidirectional cavopulmonary shunt, and 51 patients after the Fontan operation. Interventions Chest CT scans were reviewed. Measurements and Main Results: Sternal length was defined as the distance from the suprasternal notch to the xiphisternal junction. The optimal level of external cardiac compression was defined as the level at which the cross-sectional area of the systemic ventricle was the largest. The distance from the suprasternal notch to this level over the sternum was calculated. The structures below the intermammary line, the lower half and the lower third of the sternum, and the optimal level were determined. The level with the largest cross-sectional area of the ventricle was approximately the lower fourth of the sternum in all surgical stages: 86.5% ± 4.9% of the sternal length from the suprasternal notch before bidirectional cavopulmonary shunt, 85.9% ± 4.8% after bidirectional cavopulmonary shunt, and 86.4% ± 6.3% after the Fontan operation. The liver was not identified at any level, whereas the ascending aorta was detected in 2.2%, 3.8%, and 24.9% at the level of the lower third of the sternum, the intermammary line, and the lower half of the sternum, respectively. Conclusions: The optimal compression position in patients with a single ventricle is approximately 5–25% of the lower sternum. The optimal compression level for patients with a single ventricle is lower than that suggested in current guidelines for the normal population.

Effect of head position on laryngeal visualisation with the McGrath MAC videolaryngoscope in paediatric patients: A randomised controlled trial.

BACKGROUND The McGrath MAC video laryngoscope can improve visualisation of the glottis compared with the Macintosh direct laryngoscope. However, good visualisation of the glottis does not guarantee rapid or successful intubation because of difficulty in handling the McGrath device. OBJECTIVE We evaluated the effect of head elevation, aligning the positions of the external auditory meatus and sternal notch in the horizontal plane, on visualisation of the glottis and handling of the McGrath laryngoscope in paediatric patients. DESIGN A randomised controlled trial. SETTING The operating rooms of our tertiary care hospital. PATIENTS Forty-six children, American Society of Anaesthesiologists’ physical status 1 or 2, aged 3 to 7 years. INTERVENTION Videolaryngoscopy using the McGrath device was performed with the head either flat or elevated. MAIN OUTCOME MEASURES The percentage of glottis opening score, the use of optimisation manoeuvre and time to successful tracheal intubation were recorded. RESULTS The median (IQR) percentage of glottis opening score was higher after head elevation than when the head was flat in all patients [100 (100 to 100)% vs. 100 (90 to 100)%, P = 0.0001). The need for use of optimisation procedures (50 vs. 9%, P = 0.004) and mean (SD) time to intubation (17 ± 4 s vs. 15 ± 3 s, P = 0.008) were lower in the head-elevated group. CONCLUSION Visualisation of the glottis and handling of the McGrath MAC video laryngoscope were significantly better when the external auditory meatus and sternal notch were aligned in the horizontal plane. TRIAL REGISTRATION http://cris.nih.go.kr identifier: KCT 0001443.

Comparison of central venous catheterization techniques in pediatric patients: needle vs angiocath

A needle or an angiocath has been generally used as a route for inserting a guide wire during central venous catheterization. We compared the needle with the angiocath for ultrasound‐guided central venous catheterization in pediatric patients concerning accuracy and easiness.