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Anaesthesia for renal transplant surgery
Moderator - Prof Chandralekha Dr Jyotsna
www.anaesthesia.co.in [email protected]
Diffusion of solutes across a semipermeable membrane down conc gradient
Hemodialysis - shunt / fistula Peritoneal dialysis – IPD, CAPD,CCPD
Dialysis
Hyperkalemia unresponsive to conservative means
Refractory acidosis Volume overload Uremic pericarditis Uremic neuropathy
Indications :
Hemodialysis : Arteriovenous fistula - long term Arteriovenous shunt - short term Temporary venous catheters – short term
Access for dialysis
Needs 4 weeks to mature Complications : Thrombosis Infection Haemorrage StealPrecautions- Padding of fistula Avoid BP cuff No sampling Avoid hypotension
Care of fistula :
Peritoneum as endogenous dialysis membrane
CAPD /CCPD Access via silastic catheter
Peritonial dialysis :
advantages disadvantages
Hemodialysis – short time , better small solute removal
Need heparin ,vascular access , hypotension , poor BP control
Peritonial : steady state , higher hematocrit, better BP control , large solute removal , source of nutrition
Peritonitis , hernia back pain , obesity
Hemodialysis vs peritonial dialysis
Acute : Hypovolemia Electrolyte imbalance Disequilibrium syndromeChronic : Dialysis dementia Hypoproteinemia infections
Complications :
Better quality of life Better 5 yr survival rates 70% vs 30% Improves anaemia , peripheral neuropathy ,
autonomic neuropathy and cardiomyopathy Dialysis negatively affects success of
transplantation
Transplant Vs dialysis
Absolute contraindications : Disseminated or untreated cancer Severe psychiatric disease Irresolvable psychosocial problems Persistent substance abuse Severe mental retardation Un-reconstructable coronary artery disease
or refractory congestive heart failure
Contraindications for renal transplant
Treated malignancy Chronic liver disease History of substance abuse Structural genitourinary tract anomaly Past psychosocial abnormality
Relative contraindications :
LIVE or CADAVERLive -> related or unrelated Ideal donor Age = 18 - 60yrs Compatible blood groupNo DM or HTNPsychologically motivatedViral markers ( - )
Donors for kidney transplant :
Fully informed of risk and benefits Aware of alternative methods Willing to donate Psychosocially capableUnrelated donors – Need permission from authorization
committee
Pre op consent
Hemogram ,KFT , LFT CT angiography and urography Psychiatry , dental ,opthalmologic and
cardiac evaluation CMV antibodies DTPA scan and global GFR Immunological testing
Investigations
Good physical health ASA 1or 2 Open / laparoscopic Flank position – risk of hypotension Maintain good hydration and diuresis Mannitol before cross clamping Avoid direct acting vasopressors Post op pain – iv opioids , no NSAIDS
Anaesthetic concerns for living donors
Brain dead donors or non heart beating :Brain dead donors : Need peri op hemodynamic stabilization Metabolic and electrolyte disturbances
Intra op goals ( rule of 100 ): Systolic BP >100 mm hg Pao2 > 100mm hg Urine output > 100ml /hr Hemoglobin > 10 gm/dl CVP between 5 -10 mm Hg
Anaesthetic concerns for cadaveric donors :
Muscle relaxation needed Analgesia not required Volatile and opioids needed for
hemodynamic stability
Non heart beating donors :Long warm ischemia time
CVS :◦ Control hypertension ◦ Accelerated CAD - dyslipidemia , hypertension ,
Calcium & phosphate metabolism◦ volume overload - dialysis
Pre – operative assessment and optimization
Chronic anemia Maintain hematocrit close to 25% Erythropoietin supplementationUremic coagulopathy : deficient factor VIII , VWf and abnormal
platelet function Dialysis ,conjugated estrogen,
desmopressin, cryoprecipitate , FFP
Hematological assessment :
Hyperkalemia – K >5.5 need treatment Dialysis or pharmacological intervention Calcium phosphate product > 60 -
calcification in vessel Hypermagnesemia - enhance muscle
relaxants
Fluid and electrolytes :
Hypoalbuminemia or volume overload– risk of pulmonary edema
Pleural effusion Dialysis , albumin supplementation
Pulmonary status :
26
DM Stiff joint syndrome Autonomic neuropathy Silent MI Peripheral neuropathy Electrolyte imbalance Diffuse atherosclerosis Ensure blood sugar control
Risk of haemodynamic fluctuation Risk of gastric aspiration Reduced heart rate variability >15 / min is
normal
Autonomic neuropathy:
ABO compatibility HLA matching Crossmatching negative PRA( panel reactive antibody) levels ideally
less than10%
Immunological assessment :
Hemoglobin , platelets ,KFT ,LFT, CXR ,ECG, echo ,MCU, viral markers ,immunological testing
Pre op dialysis - a day prior to surgery Patients native urine output Post dialysis inv : serum electrolytes ,urea,
ECG , CXR , pt weight (<2kg difference)
Preoperative investigation
Aspiration prophylaxis – delayed gastric emptying
Dose reduction of H2 antagonists Continue antihypertensives Anxiolysis - midazolam (water solubility )
Premedication :
Standard ASA monitoring -> 5 lead ECG Pulse oximeter eTCO2 Temp NIBP ( non fistula arm ) CVP ( PAC – sig LV dysfunction ) NMT
Monitoring :
Thiopentone - ↑free fraction needs reduced dosing, slow rate of administration
Etomidate – minimal cardiodepressant effect
Ketamine - hypertensive effect ; avoid Propofol - titrated doses
IV inducing agent :
Enflurane , methoxyflurane – flouride toxicity
Desflurane , sevoflurane – safe Halothane – reduces RBF , cardiac
depressant effect Isoflurane – preserves RBF , mild
cardiodepressive effect , low renal toxicity Anesthetic agent of choice
Inhalational agents :
Morphine , meperidine – metabolites renally excreted
Fentanyl Sufentanil Alfentanil Remifentanil Doses reduced by 30-50%
opioids
Atracurium and cisatracurium - organ independent elimination
Rapid sequence induction – Succinylcholine - K < 5.5 meq/L Rocuronium – 1.5mg/kg , hepatobiliary
elimination Vecuronium – metabolite accumulation
Muscle relaxants :
Maintain asepsis Supine position , fistula care Preoxygenation Rapid sequence intubation – diabetics IV agents - thiopentone most popular
Induction :
Adequate intravascular volume - improves graft function
Maintain CVP – 10 -15 mm hgMannitol - 0.5-1 g/kg Increases renal cortical blood flow and
intravascular volume , free radical scavenger , increases release of prostaglandins
Intraoperative management :
39
Dopamine and Dopexamine Low dose Dopamine has been proved
neither a reduction in acute renal failure nor an improvement in renal function in patient with renal failure
It also did not demonstrate improved renal protection when used in cadaveric renal transplantation.
Dopexamine has been shown some renal protection during aortic surgery but its potential benefit during renal transplant has not been evaluated.
Furosemide - counteracts action of stress induced ADH release , inhibits Na –K ATPase to decrease O2 consumption , converts oliguric to non oliguric
Calcium channel blockers – verapamil injection in renal artery .Preserves RBF , reduces effects of cold ischemia
Avoid potassium containing fluids in stage 5 CKD
Medium / low molecular weight HES can be used
Albumin can be used
Fluids in renal transplant :
Adequate volume status Maintain blood pressure Avoid renal vasoconstriction Prevent tubular obstruction diuretics
Factors improving urine output
Extra caution : Intubation – avoid hypertension and
tachycardia Anastomosis - avoid hypotension,
hypovolemia and hyperkalemia Extubation - NMB fully reversed , awake
patient
Intraoperative complications :
Monitor urine output Post op analgesia – intermittent boluses of
fentanyl /morphine or PCA Potassium levels , urea and creatinine levels
measure daily Maintain adequate hydration
Postoperative period :
TIVA – propofol with fentanyl /alfentanyl/ remifentanil /atracurium
Neuraxial blocks – epidural / CSE Advantages – avoids intubation , opioids and
relaxants ,good post op analgesia Disadvantages : uremic
coagulopathy,peripheral neuropathy,hypotension ,duration of surgery
Anaesthetic techniques for renal transplant :
Warm ischemia time – from clamping of donor vessels to cold perfusion and placement to anastomosis in recipient
Duration affects acute tubular necrosis < 30 min Cold ischemia time : storage in preservation
solution to implantation in recipient Ideally < 24 hrs upto 72 hrs
Ischemia time
Mediators of ischemic injury : ATP depletion ->loss of Na K ATPase pump Movement of ions along conc gradient ->
edema and cell swelling Ischemia -> anaerobic metabolism causing
acidosis -> lysosomal disruption Free radical production
Kidney preservation :
Euro Collins solution University of Wisconsin solution Bretscheider HTK solution
Compositon : Rich in potassium ,low Na ,free radical
scavengers and other ions Static or perfused storage
Preservative solutions :
University of wisconsin soltion
Collins HTK custodial
Modified HESPotassium phosphateMagnesium sulphateAdenosineAllopurinolglutathione
Potassium phosphatePotassium chlorideSodium bicarbonateGlucoseMagnesium sulphate
HistidineTryptophanLow potassiumKetoglutrateCalciumMagnesiummannitol
agent effect toxicity
steroids ↓ interleukin production Hyperglycemia myopathy osteoporosis hypertension
azathioprine Inhibits DNA synthesis
Anaemia thrombocytopenia
cyclosporine Inhibits T cells Hyperkalemia hypertension nephrotoxicity hepatotocicity
Tacrolimus Inhibits IL 2 production
Nephrotoxicity hyperkalemia hypertension,seizures
OKT 3 Inactivates T cell Cytokine release syndromne
Immunosupressants
Induction therapy –iv tacrolimus ,MMF and methylprednisolone (2 days prior to surgery )
Maintainance therapy – same drugs on post op day 0
All three drugs continued through out life
Immunosupressents in renal transplant
1. Criteria compliance with HARRTCD4 count > 200undetectable viral loadno systemic manifestation of disease/infection
HIV positive recepient
Thank you
www.anaesthesia.co.in [email protected]