Pathophys final review part 4 Flashcards
Infants are at risk for postoperative apnea up to
60 weeks postconceptual age
-type of anesthetic is not a risk factor
Postconceptual age is
age in weeks plus gestational age
A vagotomy is
an operation when one or more branches of the vagus nerve are cut
this is done to treat patients with excessive gastric acid production & peptic ulcer disease
If a patient is vomiting, we may see
metabolic alkalosis
If a patient is having diarrhea, we may see
metabolic acidosis
Gastroschisis is
herniated viscera exposed to air
Omphalocele is
herniated viscera covered in a membranous sac & is often associated with other congenital anomalies
The BTT shunt is
a systemic to pulmonary shunt
it commonly involves connecting the subclavian artery to the pulmonary artery
risks include shunt blockage (possibly from low flow states), infection, and excessive flow to the lungs
The infant’s retina continues to develop until
44 weeks post-conceptual age
Known factors to increase pulmonary vascular tone include
hypoxemia & use of <30% fiO2 hypercarbia/acidosis hypothermia atelectasis transmitted positive pressure & PEEP stress response/stimulation/light anesthesia
Known factors to decrease pulmonary vascular tone include
increasing inspired oxygen to 100%
hyperventilation
potent inhalation agents reduce SVR more than PVR
nitric oxide
Chronic Fontan complications include
dysrhythmias
protein losing enteropathy
thrombosis
The PDA can be kept open with
prostaglandins
HLHS is a term used to
describe a spectrum of defects with the common denominator being under development of the heart’s left side
-aorta, aortic valve, LV, & MV
Describe the Norwood with shunt
connection between systemic to pulmonary circulation
anticipate oxygen saturation 75-80%
RV ejects into the systemic circulation
Describe the Bidirectional Glenn
requires low PVR & blood flow is passive
expected arterial oxygen saturation is 75-85%
direct anastomosis between the SVC & pulmonary artery branch
Describe the Fontan procedure
the inferior vena cava is connected to the pulmonary vasculature
allows for passive blood flow from the IVC to lungs while bypassing the heart
completes the separation of the pulmonary & systemic circulations
expected arterial oxygen saturation is 88-93%
TOF includes
VSD, RVOT, RVH, & overriding aorta
_____ may be used to treat pulmonary hypertension
Nitric oxide
The patent ductus arteriosus can be closed
medically via indomethacin or ibuprofen or surgical therapy
Describe where preductal and postductal measurement takes places
preductal- right arm
postductal- lower limb
Necrotizing enterocolitis anesthetic management includes
aspiration risk may necessitate RSI
inhalation agents poorly tolerated–> narcotic technique & avoid nitrous oxide
vasopressors required typically
large fluid loss & blood loss
Inguinal hernia repair, be prepared to see
laryngospasm when the surgeon pulls on the hernia sac if there is inadequate depth of anesthesia
Infants with _____ type hernia are more likely to have concurrent birth defects including CHD & chromosomal abnormalities
Bochdalek-type
CDH is a potentially lethal anomaly due to
pHTN, pulmonary hypoplasia, & associated cardiac or congenital defects
Anesthetic management for CDH repair includes
avoid mask ventilation place NG tube Pre & post ductal monitoring reactive pulmonary vasculature give paralysis and narcotics while avoiding nitrous oxide
Omphalocele is typically
associated with genetic, cardiac, urologic, & metabolic abnormalities
High intra-abdominal pressures >_____ are poorly tolerated with omphalocele & gastrochisis
20
c
Criteria for aborting primary closure of omphalocele & gastrochisis includes
end-tidal CO2 >50
max ventilatory pressure >35
intra-gastric pressure & intravesical pressure >20
Describe VATER & VACTERL
vertebral abnormalities, imperforated anus, congenital heart disease, tracheo-esophageal fistula, renal abnormalities, and limb abnormalities
associated with tracheoesophageal fistula
When inducing a neonate for tracheoesophageal repair,
maintain spontaneous ventilation
place ETT between fistula & carina
avoid nitrous
Crohn’s disease vs. ulcerative colitis.
Crohn’s disease will affect anywhere in the tract
UC targets the colon
both have an autoimmune component
Gastrin stimulates
parietal cells to release HCl
gastrin is released from G cells
Cholecystokinin is released from
I cells as a result of protein, fat, & acid
Proton pump inhibitors work by
inhibiting the parietal cell H+/K+ exchanger ATPase pump
PPIs are more effective than H2 antagonists
H2 receptor antagonists work by
selective, reversible inhibition of H2 receptor mediated secretion of H+ ions
Sympathetic response of the GI tract
will cause decrease gastric motility
Water absorption occurs in
small intestine (ileum)
Risk factors for apnea include
low birth weight, anemia, hypothermia, sepsis, neurological abnormalities, & type of surgical procedure
apnea is inversely related to postconceptual age
For retinopathy of prematurity, the anesthesia saturation goal is
90-94%
Normoglycemia for infants is
45-90 mg/dL
Four routes of heat loss in the infant include
radiation (39%), >convention> evaporation> conduction
At birth the liver is
somewhat incomplete
cytochrome P450 reaches ~50% adult values at birth
phase II are impaired until 1 year
The ductus arteriosus remains patent in utero due to
hypoxia, mild acidosis, & placental prostaglandins
Describe blue vs. pink lesions.
pink lesions- L to R shunts- connects arterial and venous circulation resulting in increased pulmonary blood flow
blue lesions- R to L shunts- venous blood is ejected systemically; there is decreased pulmonary blood flow & patients are cyanotic
Eisenmenger’s syndrome is
when the shunt reverses direction when the PVR is high enough
Coarctation presents with
upper extremity hypertension
decreased lower extremity pulses & LVH
The Ross procedure is where
the diseased aortic root is resected the patient’s own pulmonary valve root is excised & implanted into the aortic position
advantages: free from long-term anticoagulation & the valve grows as the patient grows
disadvantage: single valve disease is treated with 2 valve procedure
Describe class vs. modified BTS
classic- subclavian artery is divided & directly anastomosed to the ipsilateral pulmonary artery
modified- synthetic shunt between the subclavian artery & PA; hypotension leads to sluggish flow & possibly thrombosis
SBE prophylaxis dose is
50 mg/kg of cefazolin
doxycycline if allergy exists
TET spell is a
acute dynamic increase in the pulmonary outflow tract obstruction that may result in a cyanotic episode due to right to left shunting
Intraoperative treatment of a TET spell includes
100% oxygen knees to chest fluid bolus hyperventilation sedation esmolol phenylephrine
Anesthetic considerations for the elderly include
decrease induction agents by 50%
Two major structural effects in blood vessels of the elderly include
stiffening & atherosclerosis
Additional CV considerations for the elderly include
systolic function is abnormal (increases) and diastolic does not so see widened pulse pressure
increased incidence of dysrhythmias
Decreased sensitivity to beta-adrenergic modulation***
The most common complication and leading cause of death in the postoperative period for the elderly is
myocardial infarction
The respiratory system of the elderly has
FRC increases with age
closing volume exceeds FRC in supine position at 45 and exceeds FRC in upright position at 65
more prone to respiratory failure
reduced oxygen exchange at alveolar level
more prone to atelectasis because increased tendency for airways to close
residual volume increases
Elderly individuals have an
increased risk of aspiration**
due to decreased ability to clear secretions & attenuated protective cough mechanisms
The aging kidney is
more susceptible to injury
Hepatic function in the elderly
decreased metabolism
prolonged half-life
phase 1 drug metabolism is variable
phase 2 drug metabolism is not significantly affected
serum albumin decreases while alpha 1 acid glycoprotein increases
A major risk factor for CV disease is
diabetes
____ is more pronounced and lasts longer in the elderly
hypothermia
Frailty is
an independent predictor of in-hospital mortality
a state of reduced physiologic reserve
Diminishing cognitive performance over any time interval is
predictive of an earlier death
______ is the norm in the elderly patient
polypharmacy
Drug dosages in the elderly should be adjusted for
smaller lean body mass
The ideal induction agent for the elderly is
etomidate
Primary risk of opioids in the elderly is
respiratory depression
-reduce dose
_____ is not recommended in the elderly
meperidine
The NMBD of choice in the elderly is
cisatricurium
Poor functional status is a risk factor for
SSI & postoperative complications
Additional drugs that should be avoided in the elderly include
metoclopramide meperidine NSAIDs transdermal fentanyl agonist-antagonist opioids methadone
______ has worse outcomes than ______ surgery in the elderly.
emergent; elective
The most common postoperative complications for the elderly include
cardiac, pulmonary or neurologic complications
Increased number of clinical risk factors leads to
increased risk of surgical procedure & overall poor outcomes
The two most important factors for perioperative outcomes include:
surgical risk of the procedure
number of defined clinical risk factors in patient
____ is common after major surgery
delirium
The leading cause of morbidity is
pulmonary insufficiency or infection
