TY  - CHAP
M1  - Book, Section
TI  - Chapter 23. Evaluation of the Obese Patient
A1  - Ogunnaike, Babatunde O.
A1  - Whitten, Charles W.
A2  - Longnecker, David E.
A2  - Brown, David L.
A2  - Newman, Mark F.
A2  - Zapol, Warren M.
Y1  - 2012
N1  - 
T2  - Anesthesiology, 2e
AB  - Expiratory  reserve  volume  (ERV)  is  the  most  sensitive  indicator  of  the  effect  of  obesity  on  pulmonary  function  testing.Plasminogen  activator  inhibitor-1  (PAI-1),  secreted  by  the  endothelium,  vascular  smooth  muscle  cells,  hepatocytes,  and  adipocytes,  is  associated  with  visceral  obesity  and  inhibits  the  fibrinolytic  system.  PAI-1  decreases  fibrinolysis  and  increases  the  risk  of  coronary  artery  disease.Gastric  emptying  may  be  delayed  in  obese  patients  because  of  increased  abdominal  mass  causing  antral  distension,  gastrin  release,  and  a  decrease  in  pH  with  parietal  cell  hypersecretion.  However,  emptying  has  been  documented  to  be  faster,  with  high  energy  content  intake  such  as  fat  emulsions,  but  residual  volume  (RV)  is  increased  because  of  their  larger  gastric  volume  (up  to  75%  larger).  They  should  follow  the  same  fasting  guidelines  as  nonobese  patients.Rhabdomyolysis  has  been  documented  in  morbidly  obese  patients  undergoing  prolonged  procedures.  Elevations  in  serum  creatinine  and  creatine  phosphokinase  (CPK)  levels  unexplained  by  other  reasons  and  complaints  of  buttock,  hip,  or  shoulder  pain  in  the  postoperative  period  should  raise  the  suspicion  of  rhabdomyolysis.Difficult  laryngoscopy  and  intubation  correlates  well  with  increased  age,  male  sex,  temporomandibular  joint  (TMJ)  pathology,  Mallampati  classes  3  and  4,  history  of  obstructive  sleep  apnea  (OSA),  and  abnormal  upper  teeth,  not  the  magnitude  of  body  mass  index  (BMI).Neck  circumference  has  been  identified  as  the  single  biggest  predictor  of  problematic  intubation  in  morbidly  obese  patients.Preoxygenation  in  the  head-up  or  sitting  position  is  more  effective  and  provides  the  longest  safe  apnea  period  (SAP)  during  induction  of  anesthesia  in  obese  patients.The  head-elevated  laryngoscopy  position  (HELP)  position  significantly  elevates  the  obese  patient's  head,  neck,  upper  body,  and  shoulders  above  the  chest  to  a  point  where  an  imaginary  horizontal  line  can  be  drawn  from  the  sternal  notch  to  the  external  ear  to  better  improve  laryngoscopy  and  intubation.Positive  end-expiratory  pressure  (PEEP)  is  the  only  ventilatory  parameter  that  has  consistently  been  shown  to  improve  respiratory  function  in  obese  subjects,  but  it  decreases  venous  return,  cardiac  output,  and  subsequent  oxygen  delivery.Postoperative  continuous  positive  airway  pressure  (CPAP)  does  not  increase  the  incidence  of  major  anastomotic  leakage  after  gastric  bypass  surgery  despite  the  theoretical  risk  of  anastomotic  injury  from  pressurized  air  delivered  by  CPAP.  
SN  - 
PB  - The McGraw-Hill Companies
CY  - New York, NY
Y2  - 2024/04/19
UR  - accessanesthesiology.mhmedical.com/content.aspx?aid=56627732
ER  -