optimal perioperative fluid management h yang professor & chair department of anesthesia
TRANSCRIPT
Optimal Perioperative Fluid Management
H YangProfessor & Chair
Department of Anesthesia
Conflict of Interest
• No payment by industry• No shares in industry
Objectives
• Review fluid management principles over the years & decades
• Understand the variability of fluid shifts• Describe the physiology behind fluid
management• Discuss management principles
THE PENDULUM SWINGS
Perioperative Fluid Management
• Maintenance– 4:2:1 Rule
• Replacement– Previous losses: fasting; NG; pyloric stenosis; bleeding– Previously 1 – 2 L at start of Sx
• On-going Losses– Bleeding– Ascites– 3rd space: 1 – 2 L/hr– Sepsis
Ann Surg 1961;154:803-10
Fluid Restriction
• Lobo – 20 elective colonic resection– Restriction resulted in earlier return of bowel
function• Brainstrup – 141 colorectal surgery
– Restriction reduced incidence of anastomic leakage, pulmonary edema, & wound infection
• Holte & Kehlet – systematic review of 80 clinical trials– Avoid “fluid overload in major surgical procedures”
WE ARE NOT BUILT THE SAME!
Ann Surg 1961;154:803-10
Lindenauer et al. NEJM 2005; 353:349 - 61
Fluid Requirements
# o
f P
ati
en
ts
Elective
Major fluid shift or blood loss
3rd Space: fact or fiction?
• Tissue injury & swelling• Isotope measurements now called into
question due to kinetics of fluid shifts• Difficult to measure• Common sense: just because it is hard to
measure does not mean it doesn’t exist
PHYSIOLOGY
Total Body Water
ICF 40%(28 L)
PV 5%(3.5 L)
ISV 15%(10.5 L)
3rd space loss – 4cc/kg/hr x 4 hr = 280cc/hr x 4= 1120 cc
Maintenance – 120 cc/hr
Total Body Water
ICF 40%(28 L)
PV 5%(3.5 L)
ISF 15%(10.5 L)
Hypervolemia• Increases
leakage into ISF (endothelial glycocalyx)
Why worry about fluid replacement?
• Hemodynamic stability• Tissue perfusion
– Renal (urine output)– Surgical Site (not measureable)
It is dynamic, not static!• PAOP, CVP, & formula for replacement are all
assuming static kinetics• Preop – elective versus non-routine, bowel
prep• Intraop - anesthetic, epidural, phenylephrine
infusions, inotropes, surgical trauma, ascites, cardiac function (ischemia, diastolic dysfunction, systolic heart failure)
MANAGEMENT PRINCIPLES
Complex
TEE – IVC, hepatic vein, RWMA,
Non-RoutineNICOM, fluid challenge
Routine (elective)
Fluid restriction, monitor component losses
diastolic function
Dynamic
• Fluid restriction works for most routine cases• Be alert to the non-routine cases
– Keep track of component losses– Be ready to move up the intervention ladder:
NICOM, TEE, TTE• Be a little behind but not too much• Keep track of the pharmacology (anesthetics,
regional, vasoprressors)
• Take care of the endothelial glycocalyx!