Causes tonic clonic seizures. Exacerbated by?
Enflurane - hypocarbia and repetitive auditory stimuli
Only IA that suppresses seizure activity
Used in neurosurgery at 0.5 MAC
Can compensate for increase in ICP by hyperventilation
Desflurane Isoflurane as well - but at the time the induction agent is given
CANNOT compensate for increased ICP by hyperventilation
Enflurane - Hypocarbia can cause tonic clonic seizures
Highest amount of CO production
Desflurane Then Iso and enflurane Trace with sevo and halo
Safest for CAD with the supplementation of opioids
NO increase in CVP or RAP
Nitrous oxide Transient with desflurane and Isoflurane
Giving opioids with this agent may unmask undiagnosed myocardial depression, CAD and severe hypovolemia
Nitrous oxide - opioids take away the SNS stimulation and these patients get a profound SUDDEN bradycardia and hypotension
Autoregulation to CO2 remains UNCHANGED with these agents up to what MAC?
Sevoflurane up to 1.5 MAC Naglhout also states Desflurane as well.
Which agent offers the greatest cerebral protection from ischemia?
Isoflurane - at >1 MAC it is often used for Neurosurgery but at 0.5 MAC Due to the unchanged CBF at >1 MAC (still increased CBF) and decreased cerebral metabolic oxygen requirements Greatest uncoupling of CMRO2 and CBF
Which agent produces only a mild increase in ICP
Nitrous oxide - likely due to the inability to administer 1 MAC
Isoflurane is and Isomer of Enflurane with these key differences
1. Does not induce seizures, but rather supresses seizure activity 2. It does not increase CSF production and allows CSF outflow 3. Iso has minimal myocardial depression
IA that increases CSF production and increases resistance to CSF outflow
Which agents cause direct myocardial depression
Halothane Nitrous oxide
Which agents decrease BP is a result of the agents ability to primarily decrease SVR and have minimal myocardial depression?
Sevoflurane Isoflurane Desflurane
Gasses that have baroreceptor reflex intact
Ennflurane, Isoflurane, Desflurane
Volatile anesthetic that typically increases HR but in Elderly and Neonates this effect is blunted and Heart rate is decreased
This volatile anesthetic suppresses SA node depolarization (junctional rhythm) and decreases conduction in the bundle of his and purkinge fibers
Increases BP, HR, SVR and CO d/t SNS stimulation
Volatile anesthetic that produces DOSE DEPENDENT decrease in CO
LVSV is decreased __________% for all volatile anesthetics. Our notes say a specific one.
15 - 30% for desflurane Often times increased HR is enough to offset the decrease in stroke volume
This volatile anesthetic has a wider margin of safety between that which anesthetizes the brain and that which produces cardiovascular collapse. This means it has minimal cardiac depressant effects in the doses we use it.
Does Not have an increase in CVP or RAP
Has minimal effects on SVR
Halothane (all other volatile anesthetics decrease SVR)
_____________ increases blood flow to ____________ and ____________ areas. This distribution is similar to a ___________ effect. There is an excess perfusion relative to oxygen needs. It may manifest in the OR as ____________ due to _____________ blood flow. There also may be enhanced _______________ like NM blockers.
Isuflurane skeletal muscles and cutaneous areas ß-agonist loss of heat due to cutaneous delivery of drugs.
What is a possible explanation for the increase in cutaneous blood flow produced by all volatile gasses?
May reflect a central inhibitory action on temperature regulating mechanisms.
should be avoided in the neonate with congenital heart disease
Nitrous - d/t increased PVR which may increase the magnitude of a right to left shunt causing further decrease in arterial oxygenation.