Prof. Mridul M. Panditrao explains the problem of Peri-operative renal dysfunction

1. PERI-OPERATIVE
RENAL
DYSFUNCTION

2. Dr. M.M.PANDITRAO
CONSULTANT
DEPARTMENT OF ANAESTHESIOLOGY &
INTENSIVE CARE
RAND MEMORIAL HOSPITAL
FREEPRT, GRAND BAHAMA
COMMONWEALTH OF THE BAHAMAS

3. PERI-OPERATIVE RENAL
DYSFUNCTION
 Peri-operative Acute Renal Failure
i. Pre-existing pre-op risk factor
ii. Intra-operative event
 ESRD /CRF Patient requiring care

4. POARF : Principles
• Pre-disposing pre-op risk factors
• Physiology of Urine Production
• Differentiate and Manage causes
• Effects of Anaesthetics and Surgery
• Prevent insults of these on Kidneys

5. RISK FACTORS
• Systemic Diseases: CRF, DM,
• Jaundice
• Advanced Age
• Poor Myocardial Function
• Nephro-toxic drugs: recently used
• On CPB

7. PHYSIOLOGY OF URINE PRODUCTION
•

8. AETIOLOGY OF POARF
• Pre-Renal
i. Ac.hypovolemia & hypotension
ii. Poor cardiac function
iii. Hepatic Failure
• Post-Renal : Obstructive Pathology

9. AETIOLOGY OF POARF (
CONTD.)
• INTRINSIC ARF (RENAL)
i. Prolonged ischemia: aortic cross-
clamping
ii. Myoglobinuria
iii. Haemoglobinuria : transfusion reaction
iv. Nephro-toxics
v. Renal Artery Thrombosis/ embolism
vi. Renal Vein Thrombosis
vii. Interstitial Nephritis/ Ac. GN/ Vasculitis

10. PATHOPHYSIOLOGY OF RENAL ISCHEMIA
RENAL ISCHEMIA
>Decreased renal perfusion
Hypoxic injury to renal tubules
Tubular endothelial swelling
Vascular congestion within outer medulla
Sloughing of tubular necrotic debris
Tubular obstruction
Increased backpressure in Bowman’s capsule
decreased GFR increased backleak of ultra-filtrate
OLIGURIA

11. Diagnosing aetiology of ARF
urinary indices of ARF
PRE INTRINSIC
Urine Na+ (meq/ lit.) <20 >40
Urine Osmo.(mosm/ lit.) >500 <350
Fractional excretion of Na <1 >2
( FeNa)*
Renal Failure Index(RFI)** <1 >2
Urine sediments Clear/ Brown
casts granular casts
• *FeNa = Urine Na/ Plasma Na X 100 ** RFI = Urine Na
Urine creat/ Plasma Creat Urine creat/ Plasma creat

12. Management of Intra-op Oliguria
prevention & treatment
• Euvolemic state + stable haemodynamics
• Patent Foley and adequate BP
• CVP
• Review Blood loss
• Expand Blood volume
• PA catheter & PCWP
• Check Hb / Haematocrit / Urine for indices

13. Management of Intra-op Oliguria
prevention & treatment ( cont.)
• If no Invasive --- 2 simple tests
• Inspite of Volume loading  low C. O.
Dopamine / Dobutamine / adrenaline
• Loop Diuretics
• Mannitol ?????
• Under Trial : ANP & Urodilatin
• Vasoactive renal protective drugs:
PGs, Endothelin antagonists, Theophylline,
Calcium Channel Blockers

14. PERIOPERATIVE
MANAGEMENT OF
ESRD/ CRF

15. End Organ Effects of ESRD
 NS – Uremia : sedation, fatigue, encephalopathy
- Ch. Dialysis : dementia, dialysis diseqilibrium
** Sensitivity to sedatives/hypnotics/IVAs/ Inhalationals
- Uremia : Peripherral & autonomic neuropathy
*** autonomic Neuropathy - Haemodynamic instability
$$ Medico-legal implications
 CVS – Hyperlipidemia—atherosclerosis ---
hypertension—DM---IHD/ LVH/ LVF/ CHF
Pericarditis
 ―Leaky Pulm. Capillary Syndrome‖--- Pulm.Oedema

16. End Organ Effects of ESRD
(cont.)
• BLOOD: Anemia, Platelet dysfunction,
Blood Transfusion – Caution
Uremic toxins
• ELCTROLYTES: K+
: Ca+, PO4---, Bone
―Renal Osteodystrophy‖
• ACIDOSIS : HCO3- ???
• INFECTIVE : A-V Grafts / antibiotics
Hepatitis

17. Pre-op. Concerns of ESRD
• Strict evaluation of End-Organ damage
• Review of last Dialysis record
• Review of Aetiology of C R F
• Avoid K+ containing I V fluids : R L
• Review recent electrolytes, urea.
Creatinine
• Care and safety of A V Fistula

18. Intra-operative
• INDUCTION: Sensitivity to IVAs, etc.
multifactorial --- * hypoproteinemia
* uremia
* Free active metabolites
* Met.acidosis… free
fraction
Dose, Route, Speed, Concentration etc. of Inj.

19. Intra-operative (cont.)
• INTRA-VASCULAR VOLUME
• AUTONOMIC NEUROPATHY
• L V DYSFUNCTION
• INHALATIONALS
• OPIOIDS
• NMBDs : Benzylisoquinoliniums
Vs.
Amino-steroids
Succinyl Choline

20. Post-operative
• Reversal
• Ventilatory Support ????
• Nursing Care

21. CONCLUSION
• RENAL DYSFUNCTION IS A PROBLEM
• ESPECIALLY PERI-OPERATIVE ARF
• UNDERSTANDING AETIO-PATHO
• DIAGNOSING THE CAUSE
• INVESTINGATING & MANAGING
• ESRD / CRF VERY CHALLENGING