Anesthesia for Uremic Patients Flashcards
preoperative considerations in uremic patients
complete PE
CBC
chemistry
blood type/crossmatch
preoperative volume status concerns
hypovolemic - risk of hypotension, treat w/ fluids
hypervolemic - risk of pulmonary edema, treat with fluid restriction and diuretics
preoperative perfusion concerns
if poor - concerned about lactic acidosis, treat with fluids
preoperative uremia concerns
if unable to excrete uremic toxins - concerned about uremic acidosis, treat with fluids + sodium bicarbonate
preoperative potassium concerns
if hyperkalemic - concerned about arrhythmias, treat with fluids, dextrose/insulin, ca gluconate
preoperative concerns for patients on ACE inhibitors
CKD –> right shift in renal autoregulation curve (narrower range of systemic BP fluctuations in which the kidneys can maintain GFR)
CKD patients require a HIGHER systemic BP to maintain GFR
AVOID using ACE inhibitors on the day of the procedure
what is the most critical component of managing a renal patient under anesthesia
fluid therapy
want to use fluids to improve hemodynamic status, acid base status, and electrolyte imbalances
preoperative fluid goal
replenish any deficits over 18-24 hours prior to surgery
what fluid type should be avoided in renal patients
hetastarch due to risk of AKI
NaCl because causes acidemia
when is the use of blood products indicated
- significant anticipated blood loss
- patient unable to compensate well with low PCV
- rapid blood loss
- alterations in lactate, base excess
- degree of anemia - PCV < 20%
what is the most life threatening electrolyte abnormality
hyperkalemia
increases resting membrane potential –> slows conduction velocity in heart –> loss of myocardial excitability
what should preop K+ be prior to anesthesia
K < 6 mEq/L
what predmedications are good to use in uremic patients
opioids - minimal CV effects
benzodiazepines - minimal CV and respiratory effects
what predmedications are poor to use in uremic patients
acepromazine - causes vasodilation and hypotension + irreversible
alpha-2 agonists - profound CV effects; must be careful with dosing
best premed regimen for uremic patients
opioid + benzodiazepine
induction protocol for uremic patients
propofol or alfaxalone + midazolam
ketamine + midazolam
- except in renal cats due to long recovery
can do etomidate if concurrent heart disease
isoflurane vs sevoflurane for uremic patients
isoflurane
sevo may release compound A which is nephrotoxic
goal blood pressure in uremic patients
MAP > 60
systolic > 90
if chronic hypertension: want MAP > 70-80
are renal patients predisposed to hyper or hypothermia
hypothermia
ideal UOP during procedure
1.5-2.5 mL/kg/hr
what drugs can be used to protect the kidneys
dopamine (improve perfusion)
fenoldopam
what analgesia should be avoided in renal patients
NSAIDs - can use postoperatively only but avoid if severe/unstable renal disease
