RT Book, Section
A1 Yaster, Myron
A1 Rossberg, Mark I.
A2 Longnecker, David E.
A2 Brown, David L.
A2 Newman, Mark F.
A2 Zapol, Warren M.
SR Print(0)
ID 56626284
T1 Chapter 19. Preoperative Assessment of the Newborn
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=56626284
RD 2024/04/19
AB It  is  our  belief  that,  except  for  extraordinary  circumstances,  all  newborns  require  anesthesia  for  surgery.Maternal  factors  associated  with  increased  perinatal  risk  include  hypertension,  diabetes,  prolonged  rupture  of  membranes,  drug  abuse  (tobacco,  alcohol,  opioids,  amphetamines)  and  use  (antipsychotics,  antidepressants,  anticonvulsants),  collagen  vascular  disease,  and  maternal  infection  (prolonged  rupture  of  membranes)  or  inflammation.Small  for  gestational  age  and  large  for  gestational  age  babies  often  have  glucose  homeostatic  instability  and  require  10%  glucose  infusions  to  maintain  normoglycemia  (45-100  mg/dL).The  definition  of  prematurity  is  an  infant  born  at  less  than  37  weeks  of  gestation.The  younger  the  infant,  the  more  fragile  the  neurologic,  pulmonary,  and  gastrointestinal  systems  and  the  more  likely  the  severity  of  complications.The  presence  of  1  congenital  anomaly  should  always  alert  the  anesthesiologist  to  the  potential  for  others.It  is  always  a  good  idea  to  check  this  site  (http://www.ncbi.nlm.nih.gov/omim)  before  the  induction  of  anesthesia,  particularly  if  you  are  unfamiliar  with  the  syndrome,  defect,  or  malformation  and/or  its  anesthetic  implications.A  good  rule  of  thumb  to  remember  is  that  the  presence  of  any  midline  defect  is  almost  always  associated  with  another  defect.The  newborn  is  an  obligate  nose  breather.The  narrowest  part  of  the  infant's  airway  is  at  the  level  of  the  cricoid  ring  and  not  the  vocal  cords.The  weight  in  kilograms  +  6  is  where  the  endotracheal  tube  in  centimeters  should  be  taped  at  the  lip.Increasingly,  cuffed  endotracheal  tubes  are  being  used  even  in  the  newborn,  particularly  in  situations  in  which  aspiration  of  gastric  content  or  poor  lung  compliance  makes  ventilation  with  an  uncuffed  endotracheal  tube  difficult.Oxygen  consumption  in  the  newborn  is  2  to  3  times  that  of  older  children  and  adults.A  history  of  prematurity  (ie,  <37  weeks  postconceptual  age)  or  apnea  must  alert  the  anesthesiologist  to  possible  respiratory  compromise  in  the  postoperative  period,  particularly  if  an  opioid,  vapor,  or  ketamine  are  used  during  anesthesia.  Indeed,  premature  infants  are  at  risk  of  developing  postanesthetic  apnea  for  weeks  after  birth  (48-60  weeks  postconceptual  age)  and  require  overnight  admission  to  a  high-surveillance  in-hospital  care  unit  regardless  of  the  surgical  procedure  performed.Arterial  hypoxemia,  hypercarbia,  hypothermia,  pain,  or  acidosis  will  reverse  this  transitional  circulation  and  restore  the  fetal  circulatory  pattern  and  is  referred  to  as  persistent  fetal  circulation  or  persistent  pulmonary  hypertension  of  the  newborn.An  intravenous  infusion  of  prostaglandin  E1  to  maintain  the  patency  of  the  ductus  arteriosus  may  be  life-sustaining  in  these  ductal-dependent  patients.The  newborn's  myocardium  is  less  compliant  than  that  of  the  adult  or  older  child,  and  cardiac  output  is  primarily  heart  rate  dependent.The  most  common  cause  of  bradycardia  in  the  newborn  is  hypoxia,  and  in  the  operating  room,  unexplained  bradycardia  should  always  be  considered  to  be  due  to  hypoxia  until  proven  otherwise.The  central  nervous  system  is  the  least  mature  major  organ  system  at  birth.  This  structural  immaturity  predisposes  the  newborn  to  certain  risks,  including  intraventricular  hemorrhages,  seizures,  respiratory  depression,  hypoxic–ischemic  injury,  and  retinopathy  of  the  premature.Intraventricular  hemorrhage,  in  which  subependymal  hemorrhage  occurs,  is  now  the  leading  cause  of  death  and  morbidity  in  premature  infants.Evaporative  heat  loss  is  the  major  source  of  heat  loss  in  the  perioperative  period.The  newborn's  ability  to  concentrate  ...