RT Book, Section
A1 Hess, Dean R.
A1 Kacmarek, Robert M.
A2 Longnecker, David E.
A2 Brown, David L.
A2 Newman, Mark F.
A2 Zapol, Warren M.
SR Print(0)
ID 56631094
T1 Chapter 32. Monitoring Respiratory Function
T2 Anesthesiology, 2e
YR 2012
FD 2012
PB The McGraw-Hill Companies
PP New York, NY
SN 978-0-07-178513-6
LK accessanesthesiology.mhmedical.com/content.aspx?aid=56631094
RD 2024/04/19
AB Arterial  blood  gases  are  used  to  assess  oxygenation,  ventilation,  and  acid–base  balance.The  right-to-left  shunt  fraction  is  the  gold  standard  index  of  oxygenation  efficiency  in  the  lungs.Dead  space  is  that  portion  of  the  minute  ventilation  that  does  not  participate  in  gas  exchange.Acid–base  balance  is  explained  by  the  Henderson-Hasselbalch  equation  or  the  strong  ion  difference.Whereas  arterial  blood  gases  primarily  reflect  lung  function,  venous  blood  gases  reflect  the  adequacy  of  tissue  oxygenation  and  tissue  carbon  dioxide  clearance.Pulse  oximeters  pass  2  or  more  wavelengths  of  light  through  a  pulsating  vascular  bed  to  measure  arterial  oxygen  saturation,  carboxyhemoglobin,  and  methemoglobin.The  role  of  monitoring  cerebral  oxygenation  in  patients  with  traumatic  brain  injury  is  unclear.Capnometry  is  the  measurement  of  CO2  at  the  airway  opening  during  the  ventilatory  cycle.The  use  of  capnometry  to  monitor  procedural  sedation  is  controversial.Current  standards  recommend  the  use  of  capnography  to  assess  the  quality  of  cardiopulmonary  resuscitation.Transcutaneous  Po2  is  measured  with  a  Clark  electrode  and  transcutaneous  Pco2  is  measured  using  a  Severinghaus  electrode.Pulmonary  mechanics  is  the  expression  of  lung  function  through  measurements  of  pressure  and  flow;  from  these  measurements,  a  variety  of  derived  indices  can  be  determined,  such  as  volume,  compliance,  resistance,  and  work  of  breathing.