1) Chronic kidney disease is defined as either kidney damage or decreased glomerular filtration rate (GFR) below 60 mL/min/1.73m2 for at least three months.
2) Fluid therapy for patients with chronic kidney disease undergoing surgery aims to prevent hypo- and hypervolemia as well as electrolyte abnormalities while avoiding exacerbating kidney injury or progression to end-stage renal disease.
3) Goal-directed fluid therapy utilizing dynamic parameters like stroke volume variation is recommended over liberal or restrictive regimens, with choice of isotonic crystalloid like Plasmalyte over normal saline given risks of hyperchloremia with the latter.
2. Criteria for definition of Chronic Kidney
Disease
1. kidney damage for 3 months or more, as defined by structural
or functional abnormalities of kidney with or without
decreased GFR manifested by either
• Pathological abnormalities
• Markers of kidney damage, including abnormalities of blood
or urine abnormalities in imaging tests.
2. GFR <60ml/min/1.73 m²for≥ 3 month with or without kidney
damage.
2
3. STAGES OF CK D
Modified from National Kidney Foundation. K/DOQI Clinical Practice Guidelines
for Chronic Kidney Disease:evaluation,classification and stratification. Am J
Kidney Dis 39:suppl 1, 2002 .
3
10. Goals of fluid therapy
• Prevent hypo & hyper volemia
• Prevent electrolyte abnormalities
• Prevent acidosis
• Prevent immediate post op dialysis
To avoid the progression of CKD to ESRD or
Acute on chronic renal failure.
10
12. Fasting period
Third space loss
Maintenance
& Blood loss
Hypovolemia
&
Hypotension
Acute kidney injury
Why we need to give fluids ?
12
13. Fasting fluid – should we replace ?
• Even prolonged fasting – no decrease in absolute blood volume
• Modern fasting guideline – fluids upto 2 hours before surgery
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14. Third space - fact or fiction?
No replacement for third space loss
Jacob M et al
Best Pract Res Clin Anaesthesiol. 2009
Third space Endothelial glycocalyx
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15. Assumption Problems With Assumption
The patient is fasted preoperatively and is thus hypovolemic. BUT current fasting guidelines allow water ingestion up to 2 hours
prior to surgery. The so-called fluid deficit in elective surgery is
negligible
Insensible losses continue during surgery and must be accounted for. BUT with laparoscopic and other minimally invasive surgery there is
little insensible loss
Fluid shifts to the “third space” must be replaced. BUT it is unlikely that the “third space” exists
Blood loss must be replaced with three to four times the amount of
crystalloid.
BUT there should be an assessment of fluid responsiveness to guide
administration of fluid after blood loss
Hypotension following induction of anaesthesia is due to vasodilation,
and the vascular space must be filled.
BUT anaesthetic-induced vasodilation is better managed with
vasopressors and/or lighter anaesthesia to maintain peripheral
vascular resistance
Urine output must be taken into consideration and replaced BUT antidiuretic hormone excretion (ADH) during surgery makes
urine output as a guide very unreliable.
Even if the patient has an excessive intravascular volume, the kidneys will
regulate.
BUT the kidneys are already stressed by ADH, and it may take days
or weeks to excrete large fluid load 15
16. ASSUMPTIONS PROBLEMS WITH ASSUMPTIONS
PREOPERATIVE FASTING THUS
HYPOVOLEMIC
CURRENT FASTING GUIDELINES ALLOW WATER INGESTION UP TO 2 HOURS PRIOR TO
SURGERY
INSENSIBLE LOSSES CONTINUE DURING
SURGERY
LAPAROSCOPIC AND OTHER MINIMALLY INVASIVE SURGERY THERE IS LITTLE
INSENSIBLE LOSS
FLUID SHIFTS TO THE “THIRD SPACE” MUST
BE REPLACED.
IT’S UNLIKELY THAT THE “THIRD SPACE” EXISTS
BLOOD LOSS MUST BE REPLACED WITH
THREE TO FOUR TIMES THE AMOUNT OF
CRYSTALLOID
THERE SHOULD BE AN ASSESSMENT OF FLUID RESPONSIVENESS TO GUIDE
ADMINISTRATION OF FLUID AFTER BLOOD LOSS
HYPOTENSION FOLLOWING INDUCTION OF
ANAESTHESIA IS DUE TO VASODILATION,
AND THE VASCULAR SPACE MUST BE
FILLED.
ANAESTHESIA INDUCED VASODILATION IS BETTER MANAGED WITH VASOPRESSORS
URINE OUTPUT MUST BE TAKEN INTO
CONSIDERATION AND REPLACED
ANTIDIURETIC HORMONE SECRETION (ADH) DURING SURGERY MAKES URINE OUTPUT
UNRELIABLE
EVEN IF THE PATIENT HAS AN EXCESSIVE
INTRAVASCULAR VOLUME, THE KIDNEYS
WILL REGULATE THE FLUID LOAD
KIDNEYS ARE ALREADY STRESSED BY ADH, AND IT MAY TAKE DAYS OR WEEKS TO
EXCRETE LARGE FLUID LOAD
18. Monitoring urine output
GFR of individual
nephrons
No.of functioning
nephrons
GFR
• Essential to maintain volume and
hemodynamics
• To prevent acute on chronic renal failure
• NOT a reliable marker of renal function
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19. Monitoring & Goals
High risk
Moderate
Low risk
< 180 min > 180 min Surgical time
Patient risk
HR, NIBP
Urine output
SVV, PPV
SV, CI, DO2 GDT
Restrictive
Liberal
Della Rocca et al, BMC Anesthesiol. 2014
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21. Enhanced recovery after surgery (ERAS) protocol
Fluids targeting cardiac output – strongly recommended
Fluid management – independent predictive factor for post-op. outcome
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22. Compared with the liberal fluid
approach, GDT is superior in terms of
riskof postoperative complication.
GDT is a term used to describe use of
cardiac output or similar paremeters
to peri-operatively guide I.V. Fluids &
inotropic therapy.
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