PROBLEM TO BE SOLVED: To provide an oxygenator capable of preventing hollow fiber membranes from being partially obstructed by dew condensation water and, even when being used over a prolonged period, preventing deterioration in gas exchange properties.SOLUTION: The oxygenator includes: a housing hollow fiber membrane bundles stored in the housing and formed by accumulating multiple hollow fiber membranes having gas permeability a gas inflow part and a gas outflow part that are provided on an upstream side and a downstream side of gass passages respectively, with a lumen of each hollow fiber membrane bundle defined as the gas passage and a blood inflow part and a blood outflow part provided on the upstream side and the downstream side of blood passages respectively, with the outside of each hollow fiber membrane bundle defined as the blood passage. A gas-side pressure loss when the gas flow rate inflowing from the gas inflow part is 60% of the maximum blood flow rate of the oxygenator, is higher than Pf obtained by an expression of Pf*(π*d2/4)+π*d*γ*cos θ=0.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2016,JPO&INPIT【課題】結露した水によって中空糸膜が部分的に閉塞されることを防止でき、長時間使用してもガス交換性能が低下しない人工肺を提供する。【解決手段】ハウジングと、ハウジング内に収納され、気体透過性を有する中空糸膜が多数本集積された中空糸膜束と、各中空糸膜束の内腔をガス流路として、ガス流路の上流側および下流側にそれぞれ設けられたガス流入部およびガス流出部と、各中空糸膜束の外側を血液流路として、血液流路の上流側および下流側にそれぞれ設けられた血液流入部および血液流出部と、を備える人工肺であって、ガス流入部から流入するガスの流量が人工肺の最大血流量の60%の流量である場合におけるガス側圧力損失が、Pf・(π・d2/4)+π・d・γ・cosθ=0の式より得られるPfよりも高い。【選択図】図1
