Patho-physiological consequences of ESRD Anaemia -Transfusion Uremic Coagulopathy Uremic Cardiomyopathy Se.K+& acid-base status Delayed gastric emptying Erythropoietin Normocytic normochromic anaemia Hypertension, CVA, Thrombosis of fistulas Sensitization of the recipient Abnormal platelet function Factor 8 Pre-operative dialysis Toxins l- guanidinosuccinate,phenol Phenolic acid Hyperkalemia Acidosis Treatment-Dialysis Delays recovery -Anaesthesia
Pre-operative dialysis Optimize fluid and electrolyte balance Correct hemostatic abnormalities Post dialysis weight loss of >2 kg -Indicate intra-vascular volume depletion - Thromboplastin time is checked for residual heparin - Hepatitis can be endemic
Pre-operative optimazisation Adequate BP control Adequate control of blood glucose Correction of se.K+ levels. Correction of anaemia Correction of coagulopathy
Sevoflurane Fluoride CompoundA Fresh gas flow rates >4 L/min
Opioids Morphine Pethedine Fentanyl, sufentanil, alfentanil, remifentanyl Reduced clearance Accumulation of active metabolites Safer Metabolites are not potent,
Muscle Relaxant - Succinyl choline ? -not contra-indicated in pts. with ESRD 0.6 m eq/l can be tolerated without significant cardiac risk
Muscle Relaxant Pancuronium Vecuronium Atracurium Rocuronium Less desirable in uremia. Slight in duration Hoffmann elimination Clearance is unaffected in renal failure. Elimination half lives of anti-cholinesterases are prolonged
Special Monitors CVP monitoring Direct arterial pressure monitoring Pulmonary artery occlusion pressure TEE Contrast-Enhanced Perfusion USG Systolic BP variation correlates well with LV end-diastolic volume >20/15 1.Poorly controlled hypertension 2. CAD with LV dysfunction 3.Valvular heart disease 4.COPD when severe. Hypotension Hypovolemia or Myocardial contractility. Sonicated albumin: Predict renal viability & Guide pharmacological interventions.
Factors affecting kidney viability Management of the kidney donor(living or cadaveric). How well the harvested organ is preserved. Peri-operative management of the kidney recipient.
Anaesthetic considerations during donor nephrectomy Venous return due to the kidney -adequate hydration V/Q mismatching due to positioning Mannitol and IV heparin ( ) units before cross-clamping the renal vessels. Administration of protamine to normalize coagulation
Management of the Brain dead Kidney donor Selection -Stable hemodynamics Adequate respiratory parameters Absolute contra-indications Prolonged hypotension Hypothermia Collagen vascular diseases Congenital or acquired metabolic disorders Malignancies, Generalized viral or bacterial infections DIC’ Hep B, HIV.
Relative contra-indications Age above 70 years Diabetes mellitus High serum creatinine before organ harvesting Excessive pre-terminal use of vaso- pressors.
Guidelines for intra-op management of the brain dead A systolic BP >100 mm Hg PaO2 >100 mm Hg Urine output >100 ml/hr Hemoglobin concentration >100 g/l Central venous pressure between 5 and 10 mm Hg
Guidelines for intra-op management of the brain dead Vasodilators -Phentolamine Hypotension- Fluid administration Pharmacological support Bradycardia - Iso-prenaline (a direct acting chronotrope) and not atropine.
Anaesthetic management of kidney recipients General Anaesthesia with controlled ventilation - Good hemodynamic stability -Better patient comfort. Regional Anaesthesia Dis-advantages: Systemic blood pressure -viability of the kidney donated. Large volumes of IVF precipitate acute LVF. Advantages It is cost-effective Complete abolition of stress response Less exposure to anaesthetic drugs
Anaesthetic considerations in the recipient Positioning – Care of the AV Fistula