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Perioperative airway problems frequently result in significant morbidity and mortality in children. Therefore, proficiency in airway management is one of the most important key elements in the safe conduct of paediatric anaesthesia. This review includes important anatomical and physiological aspects of the paediatric airway, challenges encountered, and their management with commonly available resources. The importance of early recognition and treatment of anatomical or functional airway obstruction using locally adapted algorithms is highlighted. Children deemed at risk of aspiration require a controlled rapid sequence induction with sufficiently deep anaesthesia, confirmed complete muscle paralysis and intermittent ventilation prior to tracheal intubation. The benefits of a supraglottic airway device and a cuffed tracheal tube in paediatric airway management are discussed. The primary goal of mastering the paediatric airway is to ensure oxygenation and ventilation. This requires intricate knowledge, regular practice and experience.

Background and Objective: The present study compares the accuracy of a new continuous venous oxygenation monitoring system (PediaSat Oximetry Catheter) with laboratory blood oximetry in paediatric surgical patients., Methods: Children and adolescents undergoing cardiac, orthopaedic or craniofacial surgery with major blood loss were included. A 4.5 Fr two-lumen or 5.5 Fr three-lumen central venous oximetry catheter (SPediaSatcvO2) was inserted preoperatively into the superior vena cava. After in-vivo calibration of the PediaSat system, repeated blood samples were obtained from the distal port of the venous catheter and oximetrically analysed for haemoglobin and central venous oxygen saturation (SCO-OXcvO2). Central venous oxygen saturation values measured by the PediaSat (SPediaSatcvO2) were compared with co-oximetry (SCO-OXcvO2) values from the simultaneously taken blood samples by Bland-Altman and simple regression analyses., Results: Overall, 142 data pairs from 27 patients, aged from 0.6 to 19.0 years (median 5.3 years) were analysed. SPediaSatcvO2 and SCO-OXcvO2 values ranged from 57 to 98% and from 57.1 to 95.8%, respectively. Correlation between SPediaSatcvO2 and SCO-OXcvO2 was poor with r equal to 0.28 (P < 0.0001). SPediaSatcvO2 overestimated SCO-OXcvO2 (mean bias +2.6%), but limits of agreement (+/-2 SD of bias) were unacceptably high (-14.4/+19.6%). Sensitivity and specificity of SPediaSatcvO2 to indicate a fall or rise of SCO-OXcvO2 between two subsequent measurements were only 0.42 and 0.24, respectively., Conclusion: In paediatric and adolescent patients undergoing major surgery, the PediaSat system did not reliably reflect SCO-OXcvO2 values and cannot replace repeated invasive ScvO2 assessments in the clinically relevant range of ScvO2.

Background and Objective: In-vitro performance of the PediaSat system for continuous monitoring of central venous oxygen saturation by spectrophotometry has been evaluated., Methods: PediaSat continuous fibre-optic oximetry catheters were inserted in a black testing chamber, connected with an extracorporeal circuit and filled with human whole blood. Oxygen inflow into the cardiopulmonary bypass system was varied, and the testing chamber was perfused with blood flow of 1000 ml min(-1). Oxygen saturation values measured by PediaSat (S PediaSat O2) were compared with cooximetry (S CO-OX O2) values from simultaneously taken blood samples by Bland-Altman and simple regression analyses., Results: Fifty data pairs were obtained. S PediaSat O2 and S CO-OX O2 values ranged between 28-98 and 24.9-99.5%, respectively. Correlation between S PediSat O2 and S CO-OX O2 was high with an r2 value equal to 0.96 (P < 0.0001). Overall, S PediaSat O2 only slightly overestimated S CO-OX O2 (mean bias +2.9%), and limits of agreement (+/-2 SD of bias) were acceptable (-6.8/+12.6%). Sensitivity and specificity of the first differences of S PediaSat O2 and S CO-OX O2 were 1.0 and 0.92, respectively. Subgroup analysis of S CO-OX O2 values below 70% resulted in an overestimation by S PediaSat O2, with a mean bias of +5.2% and limits of agreement of -4.7 and +15.1%., Conclusion: The current version of the PediaSat system does not reliably reflect S CO-OX O2 values below 70%, but it seems to be a useful tool providing an accurate trend of continuous central venous oxygen saturation.

Background and Objective: To evaluate the noninvasive electrical velocimetry (Aesculon) monitor for cardiac output (CO) by subxiphoidal Doppler flow measurement in children., Methods: CO was determined at the end of diagnostic or interventional cardiac catheterization for congenital heart defects. Standard ECG surface electrodes were attached in a vertical direction to the patients' left middle and lower neck, and lower thorax at the level of the heart and xiphoid process. Aesculon CO data were compared with a simultaneously measured CO by the subxiphoidal Doppler flow measurement technique. For each patient, measurements were repeated three times within 5 min. Whitney U-test, simple regression and Bland-Altman analysis were performed to compare CO values obtained by the two techniques. Data are given as range (median)., Results: A total of 36 children aged 5.7 (0.5-16.0) years were investigated. CO values obtained by Aesculon monitor [0.55-5.58 (2.62) l min] and subxiphoidal Doppler flow measurements [0.62-6.27 (3.05) l min] differed significantly between both methods (P = 0.04). Simple regression analysis revealed moderate correlation between CO values obtained from the two techniques (r = 0.5544, P < 0.001). Bias between the two methods was 0.31 l min with a precision of 1.92 l min., Conclusion: We conclude that electrical velocimetry using the Aesculon monitor does not reliably reflect absolute CO values as compared with subxiphoidal Doppler flow measurement.

The dose-response relationship of four commercially available barbiturates (methohexitone, pentobarbitone, phenobarbitone and thiopentone) and of their drug-free solutions on the production of oxygen radicals by neutrophils were tested by N-formylmethionyl-leucyl-phenylalanine (FMLP)-induced granulocyte chemiluminescence and in a cell-free chemiluminescence system. Methohexitone had no effect on neutrophil chemiluminescence. Pentobarbitone, phenobarbitone and thiopentone dose-dependently decreased FMLP-induced chemiluminescence and cell-free chemiluminescence. Suppression of neutrophil chemiluminescence by pentobarbitone and phenobarbitone was due to effects of the drug-free solutions and an osmolality greater than 360 mosmol kg-1. Only thiopentone suppressed granulocyte chemiluminescence drug-specifically. The physicochemical properties of commercially available barbiturate preparations and their solutions, as well as free radical scavenging capacity, have to be considered if these preparations are used to evaluate drug-specific effects on the production of oxygen radicals by neutrophils.