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The composition and type of intravenous fluids during paediatric anaesthesia have been subjects of debates for decades. Errors in perioperative infusion therapy in children may lead to serious complications and a negative outcome. Therefore, in this review historical and recent developments and recommendations for perioperative fluid management in children are presented, based on physiology and focused on safety and efficacy. Recent studies showed that optimized preoperative fasting times and liberal clear fluid intake until 1 h improve patient comfort and metabolic and haemodynamic condition after induction of anaesthesia. Physiologically composed balanced isotonic electrolyte solutions are safer than hypotonic electrolyte solutions or saline 0.9% to protect young children against the risks of hyponatraemia and hyperchloremic acidosis. For intraoperative maintenance infusion, addition of 1 - 2% glucose is sufficient to avoid hypoglycaemia, lipolysis or hyperglycaemia. Modified fluid gelatine or hydroxyethyl starch in balanced electrolyte solution can safely be used to quickly normalize blood volume in case of perioperative circulatory instability and blood loss. In conclusion, physiologically composed infusion solutions are beneficial for maintaining homeostasis, shifting the status more towards the normal range in children with pre-existing imbalances and have a wide safety margin in case of accidental hyperinfusion., Competing Interests: R. S. hat Forschungsunterstützung von B. Braun Melsungen und ein Vortragshonorar von Fresenius Kabi erhalten. Die anderen Autoren haben keine Interessenskonflikte., (Georg Thieme Verlag KG Stuttgart · New York.)

A volume replacement should compensate a reduction in the intravascular volume and counteract a hypovolemia so that hemodynamics and vital functions can be maintained. For this therapy, a physiologically-based solution comprising both osmotically and colloid osmotically active components should be administered. A consensus is proposed for this purpose which takes into consideration the following aspects: The optimum colloid, the questionable use of albumin, the physiological electrolyte pattern encompassing sodium, potassium, chloride and phosphate and their contributions to osmolality, an eventual addition of glucose, the physiological acid-base status with bicarbonate or alternately with metabolisable anions, and the importance of a clear declaration of all ingredients. The consensus distinguishes between compulsory requirements derived from evidence-based medicine and physiological data and the potential expectations of an optimal volume replacement, including well-grounded wishes and aspirations for the future.

Objective: The composition of normal saline (NaCl), the standard wash solution for cell saver autotransfusion, is considerably different from physiologic plasma values in small infants. Therefore, we investigated acid-base and electrolyte changes during massive cell saver autotransfusion with different wash solutions in young pigs., Methods: After approval by the animal protection authorities 15 young pigs (weight 10.6 +/- 1.1 kg, blood volume 848 +/- 88 ml, mean+/-SD) underwent 15 cycles of cell saver autotransfusion (Haemolite 2plus, Haemonetics). For each cycle, 100 ml arterial blood was withdrawn, washed with NaCl, physiologic multielectrolyte solution (PME, V Infusionslösung 296 mval Elektrolyte, Baxter) or physiologic erythrocyte protection solution (PEP, 3.2 % gelatine, pH 7.40, cHCO3 24 mmol/l), and then retransfused. Analyses of acid-base, electrolyte, and hematologic parameters were performed for systemic and washed blood samples., Results: For NaCl there was a progressive decrease in systemic pH, HCO3 and base excess (BE) and an increase in chloride values (Cl) (p < 0.05). Use of PME slightly decreased pH (n. s.), whereas HCO3, BE and Cl remained stable. PEP slightly increased pH, HCO3 and BE, and decreased Cl (n. s.). Free hemoglobin increased in NaCl and PME (p < 0.05) and was below baseline in PEP (n. s.). Lactic acid course was comparable in all groups., Conclusions: The use of NaCl as wash solution for massive autotransfusion resulted in metabolic acidosis caused by dilution of HCO3 and increased Cl values. Fewer systemic acid-base and electrolyte changes were observed, when blood was washed with PME or PEP. The decreased hemoglobin release with PEP is possibly due to a gelatine specific electrostatic surface coating of erythrocyte membranes. For massive transfusion of washed red blood cells, physiologic multielectrolyte solution and physiologic erythrocyte protection solution should be preferred to NaCl, especially for small infants.

Definitions of shock types. Hypovolaemic shock is a state of insufficient perfusion of vital organs with consecutive imbalance of oxygen supply and demand due to an intravascular volume deficiency with critically impaired cardiac preload. Subtypes are haemorrhagic shock, hypovolaemic shock in the narrow sense, traumatic-haemorrhagic shock and traumatic-hypovolaemic shock. Cardiac shock is caused by a primary critical cardiac pump failure with consecutive inadequate oxygen supply of the organism. Anaphylactic shock is an acute failure of blood volume distribution (distributive shock) and caused by IgE-dependent, type-I-allergic, classical hypersensibility, or a physically, chemically, or osmotically induced IgE-independent anaphylactoid hypersensibility. The septic shock is a sepsis-induced distribution failure of the circulating blood volume in the sense of a distributive shock. The neurogenic shock is a distributive shock induced by generalized and extensive vasodilatation with consecutive hypovolaemia due to an imbalance of sympathetic and parasympathetic regulation of vascular smooth muscles.

Capnometry, i.e. measurement of CO2 concentration (cCO2, vol%) and calculation of the respective CO2 partial pressure (pCO2, mmHg), is simple to apply, but the user must understand its principles of operation in order to appreciate its power and its limitations. However, sidestream capnometers use to dry the humidified respired gas (37 degrees C, pH2O 47 mmHg) for methodological reasons, thus increasing pCO2 by ca. 6% which, in turn, requires correction. With infrared spectroscopy, overestimation of pCO2 in presence of N2O and underreporting of pCO2 in presence of O2 also require to be corrected. These require either knowledge of the respective gas concentrations (mainstream analyzers) or adequate (i.e. correct) measurement (some sidestream capnometers). Changes in barometric pressure (pB) must be also either known or be measured automatically. Evaluation of the precision of capnometers must therefore focus on, (1) the possible pH2O correction, (2) the possible effects exercised by O2 and N2O, and (3) the possible dependence on barometric pressure. Two mainstream (Capnolog D/Dräger; Sirecust 404-1/Siemens) and eight sidestream capnometers (AGM 1304/Brüel & Kjaer; SARAcap A. G. and SARA-trans/Biomedical Systems/Hellige; Capnomac and Normocap 200/Datex/Hoyer; CO2 Monitor/Dräger; Nellcor N-1000/Nellcor/Dräger; Multinex/Datascope) were investigated. Dry and humidified gases (37 degrees C) of defined composition in respect of CO2, O2, N2, N2O, and H2O, were used for evaluation. The results prove reproducibility of ca. =/- 1 mmHg for the 10 capnometers within the 30-50 mmHg pCO2 range.(ABSTRACT TRUNCATED AT 250 WORDS)