Cac m a y b o m khf hien na y deu d u g c tu d o n g hoa. C h u n g ta c o the dieu c h i n h ap luc t rong k h o a n g ph uc m a c va luu lugng khf b o m vao the o y m u o n c u a c h u n g ta. Khf C 0 2 c o kha n a ng k h u y e c h tan vao t r ong m a u n h a n h ga p 2 0 0 lan so vdi 0 2, d u g c d ao thai n h a n h c h o n g q u a d u d n g t h d vi the c o ft n g u y c o ga y tac m a c h do khf. Khi bat dau tien h a nh lam c a n g k h o a n g p h uc mac, dieu c h i n h m a y b o m vdi a p luc 15 m m Hg, luu l u g n g khf b o m la 3 Ift/phlit (vdi kfch t h uo c ciia kim b om C O ; luu lu gn g khf di q u a k im toi da c u n g chi dat k h o a n g 2,5 Ift/phut). Lu u y ap luc t r ong k h o a n g p h uc m a c k h o n g d u g c vu gt q u a 15 m m Hg. Vdi a p luc 15 m m Hg, t ha nh b u n g du c a n g c h o p h ep c h o c c a c t roc ar dd d a ng , an toan t ra nh ga y t h u o n g ton c a c m a c h m a u ldn d trudc cot song. Dien bien c u a c ac t h o n g so a p luc t hu c t r on g k h o a n g p h u c m a c c u n g n h u luu lu g ng khf C 0 2 bo'm thuc te c h o p h e p d a n h gia vi trf c u a k i m c h o c. Khi kim b om khf n a m diing vi tri, t r ong hau het c ac tr ud ng h g p a p luc thuc te t rong k h o a n g ph uc m a c ban dau la a m tfnh (vai m m Hg). T h o n g t h u d n g the tfch C 0 2 c an phai b om de dat a p luc m o n g m u o n (15 m m Hg) la tu 3 deii 5 1ft. T r on g khi b om, c a n tiep tuc k i e m tra vi trf c u a kim b o m khf b a ng c ac c a c h sau:
- T h e o ddi dien bien ciia c a c t h o n g so ap luc va luu l ug n g thuc te tren m a y born khf.
- Mat v u n g d u e t ru dc gan (khi b o m d u g c do 2 0 0 - 3 0 0 ml C 0 2). - T h a n h b u n g t rudc c a n g len deu.