410 likes | 637 Views
Speakers : Dr Pratyush Dr Priya Moderators: Prof Chandralekha Dr Jyotsna. Post Renal Transplant : Incidental Surgery. www.anaesthesia.co.in anaesthesia.co.in@gmail.com. Magnitude of problem. Prevalence of CRF in adult population of Delhi: 0.785% (7852/million people).
E N D
Speakers : Dr Pratyush Dr Priya Moderators: Prof Chandralekha Dr Jyotsna Post Renal Transplant : Incidental Surgery www.anaesthesia.co.inanaesthesia.co.in@gmail.com
Magnitude of problem • Prevalence of CRF in adult population of Delhi: 0.785% (7852/million people)
Magnitude of problem • Prevalence CRF in India: 0.8% • Global incidence CRF: 1.8 million/year (WHO 2002) • Incidence ESRD in India: 100,000 patients/year • Prevalence of ESRD : 785/million population • Approx 3000 renal transplants/year
Status of Renal Transplant in India • Infections very common 70-80% • Bacterial chest infection m/c cause of death • TB, Hepatitis, fungal, CMV frequent • Survival:
Relevance • 3 yr patient survival figures*: • Heart-lung: 43.9% • Heart: 78% • Intestine: 53.3% • Lung: 58.3% • Liver: 79.7% • Pancreas: 86.8% • Kidneys: 90.9% • * united network for organ sharing, USA: years 1996-2001
Common surgical indications • First 48 hrs of transplant: • Rexploration for bleeding/reduced urine/thrombosis of graft • Late presentations: • Graft failure: Redo surgery • Uncontrolled hypertension-- Nephrectomy • Lymphoceles, Wound infections • Joint replacements (renal osteodystrophy, steroid) • Cesarean Sections • GI bleed, CABG, dental (gum hyperplasia)
Anesthetic challenges &preoperative assessment • Avoidance of infection: Maintain sterility • Signs of intra-abdominal sepsis..often absent • fever, leukocytosis, peritonitis signs absent • Assess/Preserve graft function: • previous episodes of rejection • BU, S.Cr, SE (Na,K,Ca,Mg) • Avoid nephrotoxic drugs
Anesthetic challenges:preoperative assessment • Assess Rejection • Azotemia, proteinuria, hypertension • Pruritis, lethargy, nausea, skin pigmentation • Care for co-morbidities: HTN, CAD, DM,CHF • Stress testing • Coronary angiography • Hyperlipidemia: • Increases perioperative CVS morbidity/mortality
Anesthetic challenges:preoperative assessment • If on Hemodialysis • Hypovolemia: CVS instability • Hypokalemia: Arrhythmias, Susceptible to MR • Steroid- lympho proliferative disorder-airway obstruction
Anesthetic challenges: Drugs • Immunosuppressants • Double edged sword • Continue perioperatively in adequate doses • Oral dose of CSA : 4-7 hrs before surgery • “Stress-coverage” steroids: if recently withdrawn Affect the choice of anesthesia
Premedication • Standard premedication may be used • BZP: duration & activity prolonged • Ranitidine: caution
Monitoring • Perioperative monitoring: risk/benefit • type of surgery • anesthesia planned • equipment available • CVP monitoring: • Transplanted kidneys sensitive to hypovolemia • Diuretic use: adequate intravascular volume • urine output
Technique • General (balanced & TIVA) as well as regional successfully used
General anaesthesia • Nasal intubation better avoided • Use of LMA acceptable • Ketamine: cautious in HTN/CAD
Inhalation Agents • Isoflurane/desflurane :appropriate • Sevoflurane :safe • Enflurane : avoided--toxic fluoride metabolites
Muscle relaxants • Atracurium, Cisatra, Miva…Vec • Delayed gastric emptying/RSI: • Sch: K<5.5 meq/L • Rocuronium, miva
Analgesia • Avoid NSAIDS: • GI Hmge, nephrotoxicity • Augment Cyclosporine A nephrotoxicity • Opiate analgesics often used • Meperidine,M3G and M6G: prolonged sedation • Remifentanyl@ 0.1-0.5 mics/kg/min: • short acting • Non specific tissue and plasma esterases
Regional anesthesia • Avoid: • uremic platelet dysfunction • Severe hypovolemia • Caution: • Azathioprine, MMF • Uremic/diabetic peripheral neuropathy • Bupivacaine safe in clinical doses
Special cases • Laproscopic surgery • Trauma • Pregnancy • Pediatric Renal transplant
Laproscopic Surgery • Laproscopic cholecystectomy as safe • Advantage: • Short hospital stay • Maintenance of oral immunosuppression • Low morbidity • Early return to preoperative routine • Disadvantage: • Higher conversion rate to open: 27% vs 11 %
Trauma • Direct blunt trauma to kidney: • Massive hemorrhage • Insidious Graft dysfunction • Same initial resuscitation as trauma victims • Complications: • DVT • Pneumonia/sepsis • Renal failure • Death
Pregnancy • No adverse effects on allograft survival • Reduced renal function by 15-20% / pregnancy • Cautious in multiparous recipient • Immunosuppressants: not to be discontd. • Nephrotoxicity • Hepatotoxicity • Cross placenta: not teratogenic • 1st T: no teratogenicity • 2/3T: transient compromise of immune system, LBW,pancreas,liver, lymphocytes
Pregnancy : Considerations • Renal dysfunction • Thrombocytopenia • Pelvic osteodystrophy • Femoral head necrosis • Hypertension • DM: strict control: 2 fold greater risk
Pregnancy…contd • Anesthetic management same • Prophylactic antibiotics • Stress dose steroids • CSE/SAB : • caution in immunocompromised • Epidural catheter safe 24-48 hrs
Pediatric Renal Transplant History: • First in a 16-year child- Michon and colleagues in Paris, 1952: Patient survived 21 days • First successful pediatric transplant by Goodwin et al, University of Oregon, 1959 between pediatric identical twins: alive at 18 yrs
Statistics • Live related (USA) : 300/year • Cadaveric : 150-200/year • Infants : 10% • Small children (<15 kg): 15% • Minimum weight requirement: 7 kg • Graft and patient survival lower: • age < 2yrs (vascular thrombosis) • Cadaveric
For the Anaesthesiologist… Providing adequate perfusion of a very large kidney relative to the recipient size to prevent vascular thrombosis and delayed graft function is one of the main challenges for the pediatric anesthesiologist
Preoperative assessment • Growth – smaller size ETT required • Congenital defects(VSD)- agenesis/hypoplasia • CHF - uremia/CHD/chronic fluid overload • Fluid overload: • Frequent episodes of asthma • Wheeze/rales/dyspnea • Hepatomegaly • Hypertension
Preoperative Assessment • H/O repeated fractures • Brittle bones • Risk of dental injury • H/O acid reflux- delayed gastric emptying • Difficult vascular access- Examine and plan • Surgery postponed for dialysis • K>6.0 meq /l • Acidosis • Fluid overload
Anesthetic management • Preoperative sedation with oral/rectal midazolam (0.5 mg/kg) • Inhaled induction: Sevoflurane + nitrous oxide • Intravenous: thiopental or propofol or ketamine • Air-oxygen mixture: prevents bowel distension– space for adult kidney • Warm fluids (N/2 saline) to prevent hypothermia and myocardial depression
Monitoring • Preplaced Hickman catheter used for CVP • Arterial monitoring useful if Aorta cross clamped: • Reperfusion of the kidney – significant hypotension • ABG
Care During Perfusion of the Allograft Older children– receiving appropriate size graft– management straightforward Infants and small children—challenging • Both aorta and IVC cross clamped • Low dose heparinisation (50U/kg) • Pooled blood in kidney & lower limbs– release ischemic products on clamp release • Ischemia induced vasodilation—more uptake (300 ml) blood by transplanted kidney • Significant hypotension: High incidence of vascular thrombosis/ ATN
Extra measures before reperfusion • Raise CVP to 18 • Packed RBCs and colloids (albumin, plasma) • Amount of fluids required may exceed 100% TBV • Systemic blood pressure: 20%>preoperative • Reduce anesthetic concentration to 0.5 MAC • Dopamine 3-5 mics/kg/min • Atropine (20mics/kg): prevent vagal reflex of sudden fall in SVR • Calcium chloride (10mg/kg): to counter K+ from preservative solution
Additional measures • Urine replaced ml to ml with N/2 saline • Fentanyl used for analgesia • Extubation in OT/post operative recovery • Post operative CXRay shows pulmonary edema in 25% patients • Less than 10% infants require postoperative mechanical ventilation www.anaesthesia.co.inanaesthesia.co.in@gmail.com