Interstitial Fluid Colloid Osmotic Pressure in Healthy Children

Abstract

ObjectiveThe colloid osmotic pressure (COP) of plasma and interstitial fluid play important roles in transvascular fluid exchange. COP values for monitoring fluid balance in healthy and sick children have not been established. This study set out to determine reference values of COP in healthy children.Materials and MethodsCOP in plasma and interstitial fluid harvested from nylon wicks was measured in 99 healthy children from 2 to 10 years of age. Nylon wicks were implanted subcutaneously in arm and leg while patients were sedated and intubated during a minor surgical procedure. COP was analyzed in a colloid osmometer designed for small fluid samples.ResultsThe mean plasma COP in all children was 25.6 ± 3.3 mmHg. Arbitrary division of children in four different age groups, showed no significant difference in plasma or interstitial fluid COP values for patients less than 8 years, whereas patients of 8-10 years had significant higher COP both in plasma and interstitial fluid. There were no gender difference or correlation between COP in interstitial fluid sampled from arm and leg and no significant effect on interstitial COP of gravity. Prolonged implantation time did not affect interstitial COP.ConclusionPlasma and interstitial COP in healthy children are comparable to adults and COP seems to increase with age in children. Knowledge of the interaction between colloid osmotic forces can be helpful in diseases associated with fluid imbalance and may be crucial in deciding different fluid treatment options.Trial RegistrationClinicalTrials.gov NCT01044641

Effect of two different colloid priming strategies in infants weighing less than 5 kg undergoing on‐pump cardiac surgeries

“…Previous study found that mean plasma COP was 25.6 ± 3.3 mm Hg in 2-10 years old healthy children, while patients of 8-10 years of age had significantly higher COP both in plasma and interstitial fluid compared with patients less than 8 years old. 9 Miao's study found 4 the average COP for on-pump cardiac surgery patients was 22.6 ± 2.2 mm Hg at CPB termination in an artificial colloid priming group, which were higher than the average COP in our study. The difference may be explained by the selection of lower weight and younger patients in our study.…”

“…The COP values of the two groups was (15.3 ± 0.6) mm Hg in the AC group versus (15.6 ± 0.7) mm Hg in the ACA group at CPB termination, and increased to (18.2 ± 0.7) mm Hg versus (18.0 ± 0.6) mm Hg after modified ultrafiltration in our study, respectively. Previous study found that mean plasma COP was 25.6 ± 3.3 mm Hg in 2‐10 years old healthy children, while patients of 8‐10 years of age had significantly higher COP both in plasma and interstitial fluid compared with patients less than 8 years old . Miao's study found the average COP for on‐pump cardiac surgery patients was 22.6 ± 2.2 mm Hg at CPB termination in an artificial colloid priming group, which were higher than the average COP in our study.…”

Cytokine and Chemokine Recovery Is Increased by Colloid Perfusates during Dermal Microdialysis

“…In our study, we investigated the RR and AR of six recombinant human cytokines of increasing molecular size using in vitro, ex vivo, and in vivo experiments. Due to their similarities to interstitial fluid and human skin [ 36 , 37 ], we used human serum and porcine skin, respectively, ex vivo and in vivo. Finally, we used excised human skin ex vivo and in vivo to find the most efficient perfusate (crystalloid or colloids) for investigating intercellular signalling in clinical trials.…”

“…The membrane and catheter were placed in syringes that were containing either Ringer’s lactate or human serum, which was chosen to mimic the interstitial fluid that surrounds the membrane when placed in living tissue. Although not identical, human serum is quite similar to interstitial fluid [ 36 , 37 ]. Furthermore, for the in vivo analysis, we subjected human and porcine skin cadavers and porcine dermal skin from anaesthetized domestic pigs to retrodialysis (i.e., inverse microdialysis).…”

Clinical Perspectives and Management of Edema in Chronic Venous Disease—What about Ruscus?

“…Within the original Starling Principle, the difference between the COP and hydrostatic pressures on alternate sides of the membrane was responsible for the net fluid shift across the membrane [ 13 ]. Within the revised Starling Principle, the COP has been determined to have a lesser role, but it does still warrant consideration [ 10 ].…”