TY  - CHAP
M1  - Book, Section
TI  - Chapter 13. Clinical Use of the Pulmonary Artery Catheter
A1  - Leatherman, James W.
A1  - Marini, John J.
A2  - Hall, Jesse B.
A2  - Schmidt, Gregory A.
A2  - Wood, Lawrence D.H.
PY  - 2005
T2  - Principles of Critical Care, 3e
AB  - Recent  randomized  trials  found  that  use  of  a  pulmonary  artery  catheter  (PAC)  did  not  influence  the  mortality  of  high-risk  surgical  patients  or  critically  ill  patients  with  shock  or  acute  respiratory  distress  syndrome  (ARDS).Insertion  of  a  PAC  is  associated  with  a  low  incidence  of  serious  complications.  Of  potentially  greater  risk  to  the  patient  than  insertional  complications  are  errors  in  recording  and  interpreting  hemodynamic  data  that  lead  to  faulty  clinical  decisions.  Several  studies  have  shown  that  there  are  serious  deficiencies  in  the  understanding  of  basic  aspects  of  hemodynamic  monitoring  among  physicians  and  nurses  who  use  the  PAC.Incomplete  wedging  can  lead  to  marked  overestimation  of  the  actual  pulmonary  artery  wedge  pressure  (Ppw)  and  always  should  be  suspected  when  the  measured  Ppw  exceeds  the  pulmonary  artery  diastolic  pressure  (Ppad).  However,  with  pulmonary  hypertension,  incomplete  wedging  may  be  present  despite  a  positive  Ppad–Ppw  gradient  and  should  be  suspected  when  the  latter  markedly  narrows  in  comparison  with  previous  values.Careful  inspection  of  the  PAC  waveforms  may  be  helpful  in  the  diagnosis  of  underlying  cardiac  disorders:  Acute  mitral  regurgitation  results  in  prominent  v  waves  in  the  Ppw  tracing,  pericardial  tamponade  is  characterized  by  equalization  of  the  Ppw  and  right  atrial  pressure  (Pra)  and  by  blunting  of  the  y  descent  in  the  atrial  waveform,  tricuspid  regurgitation  often  leads  to  a  broad  cv  wave  and  a  prominent  y  descent,  and  both  constrictive  pericarditis  and  restrictive  cardiomyopathy  result  in  prominence  of  both  the  x  and  y  descents  in  the  atrial  waveform.Over  the  range  of  values  most  often  seen  in  the  ICU,  neither  the  Pra  nor  the  Ppw  provides  a  reliable  indicator  of  the  adequacy  of  preload  and  of  fluid  responsiveness.  However,  the  change  in  Pra  with  a  spontaneous  breath  may  be  a  useful  indicator  of  fluid  responsiveness  in  that  failure  of  the  Pra  to  fall  with  inspiration  predicts  that  the  patient  is  unlikely  to  benefit  from  a  fluid  challenge.Positive  end-expiratory  pressure  (PEEP)  causes  the  measured  Ppw  to  overestimate  transmural  left  atrial  pressure;  the  effect  of  PEEP  on  transmural  pressure  can  be  quantified  by  calculating  the  percentage  of  alveolar  pressure  that  is  transmitted  to  the  pleural  space  during  a  positive-pressure  breath.  Active  expiration  also  causes  the  measured  Ppw  to  overestimate  transmural  pressure  and  usually  results  in  much  greater  errors  than  does  applied  PEEP.Thermodilution  cardiac  output  (Q̇t)  can  be  measured  by  the  intermittent  bolus  method  or  continuously  with  a  modified  catheter.  Several  noninvasive  and  minimally  invasive  methods  of  measuring  (Q̇t)  are  also  available.Venous  oxygen  saturation  in  the  pulmonary  artery  (SvO2)  or  superior  vena  cava  (ScvO2)  serves  as  a  global  indicator  of  the  adequacy  of  O2  delivery  relative  to  tissue  O2  demands.  
SN  - 
PB  - The McGraw-Hill Companies
CY  - New York, NY
Y2  - 2023/09/24
UR  - accessanesthesiology.mhmedical.com/content.aspx?aid=2282948
ER  -