Premium
Relationship between frequency of ventilation, airways and pulmonary artery pressures, cardiac output and tracheal tube deadspace
Author(s) -
Chakrabarti M. K.,
Grounds R. M.,
Swenzen G. O.,
Whitwam J. G.
Publication year - 1986
Publication title -
acta anaesthesiologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.738
H-Index - 107
eISSN - 1399-6576
pISSN - 0001-5172
DOI - 10.1111/j.1399-6576.1986.tb02501.x
Subject(s) - medicine , tracheal tube , anesthesia , cardiac output , mallinckrodt , pulmonary artery , ventilation (architecture) , airway , cardiology , hemodynamics , mechanical engineering , engineering , family medicine
Intravascular and airway pressures, cardiac output (CO) and blood gas tensions were measured in five adult patients after hepatobiliary surgery. They were ventilated at frequencies of 15, 100 and 200 breaths min ‐1 (bpm) with the respiratory fresh gas (RFG) supplied at the proximal and distal end of a Malinkrodt Hi‐Lo tracheal tube. The peak airway pressure (Paw) fell from 1.20 kPa at 15 bpm to 0.6 kPa at 100 bpm, rising again to 1.9 kPa at 200 bpm, and both changes were significant ( P <0.05). The mean pulmonary artery pressure (PAMP) remained in the range 1.87–2.00 kPa (14–15 mmHg) at 15 and 100 bpm but rose to over 2.67 kPa (20 mmHg) at 200 bpm ( P <0.05). Cardiac output, heart rate and systemic arterial pressure remained unchanged. A small but significant ( P <0.05) reduction in Paco 2 occurred when the RFG was moved to the distal end of the tracheal tube. A theoretical analysis predicts that the minimal Paw to maintain CO 2 homeostasis will occur between 30 to 100 bpm, which is reflected in the results of the present study.