Anesthesia for GU surgery Dr. Daniels

Chapter 33 Anesthesia for Genitourinary Surgery 8/12/2008 Don Daniels COL MC 1 CYSTOSCOPY  Hematuria, recurrent uTI, urinary obstruction, bladder biopsies, renal stone extraction, ureteral catheter placement  GA for children, local viscous lido for adult female, regional or GA for adult male 8/12/2008 Don Daniels COL MC 2 Lithotomy  Common peroneal injury leads to loss of foot dorsiflexion  Saphenous nerve compression can lead to medial calf numbness  Excesive flexion of thigh against groin can injure the obturator 8/12/2008 Don Daniels COL MC 3 Lithotomy  Decreased FRC  Acute increase in venous return w leg elevation can lead to CHF  Acute hypotension may result from rapid lowering of legs 8/12/2008 Don Daniels COL MC 4 Cystoscopy anesthetic choices  General employed for short outpatient procedures • Obturator reflex only abolished with muscle relaxants  Regional: for procedures lasting > 30 minutes SAB preferred with shorter onset time vs longer onset epidural • Moving legs before level “fixed” is okay • Need a T10 level • Neuraxial does not abolish the obturator reflex 8/12/2008 Don Daniels COL MC 5 TRANSURETHRAL RESECTION OF THE PROSTRATE (TURP)  0.2 -6 % mortality rate  Most common causes periop death due to MI, pulmonary edema and renal failure.  Other predominant complications due to large volumes or irrigation fluid 8/12/2008 Don Daniels COL MC 6 TURP Syndrome  Absorption of >2 L leads to symptoms • Headache, restlessness, confusion, cyanosis, dyspnea, arrhythmias, hypotension or seizures • Physiologic changes include circulatory fluid overload, water intoxication, irrigating fluid solute toxicity 8/12/2008 Don Daniels COL MC 7 TURP Syndrome Cannot use electrolyte solutions due to dispersed electrocautery current  H2O provides excellent visibility  • Lyses blood cells • Absorption causes water intoxification  Best solutions are nonelectrolyte & slightly hypotonic • 1.5% gycine (230 mOsm/L) • 2.7% sorbital & 0.54% mannitol solutions • Still can cause water & solute absorption 8/12/2008 Don Daniels COL MC 8 TURP Syndrome  Absorption of irrigation fluid dependent on • Duration of the resection • Height or pressure of the irrigation fluid • Average 20 ml/min absorbed fluid  Absorption can lead to • Pulmonary edema • Hyponatremia • Hypo-osmolality 8/12/2008 Don Daniels COL MC 9 TURP Syndrome Hyponatremia -Sx’s occur Na<120 mEq/L  Hypotonicity – Na < 100 mEq/L cause intravascular hemolysis  Hyperglycinemia  • Glycine acts as inhibitor neurotranmitter in CNS • Transient blindness • Hyperammonenia Hyperglycemia due to sorbitol or dextrose soln’s  Mannitol causes volume expansion and exacerbates fluid overload  8/12/2008 Don Daniels COL MC 10 TURP Syndrome: Treatment  Fluid restriction  Loop diuretic  Hypertonic saline @ 100 ml/hr for seizures due to hyponatremia • Benzodiazepines, thiopental, phenytoin • Endotracheal intubation 8/12/2008 Don Daniels COL MC 11 TURP bladder perforation  Poor return of irrigating fluid  Nausea, diaphoresis, retropubic or lower abdominal pain  Hypotension or HTN with diffuse abdominal pain signal large perforation  Bradycardia 8/12/2008 Don Daniels COL MC 12 TURP: Anesthesia Choices  Neuraxial anesthesia T10 sensory level • Less incidence of post op venous thrombosis • Less likely to mask TURP syndrome or bladder perf  Delayed emergence from GETA may be due to hyponatremia 8/12/2008 Don Daniels COL MC 13 Extracorporeal Shock Wave Lithotripsy (ESWL)  Pacemaker or AICD @ risk for ESWL shock wave induced arhythmias  Should contact manufacturer to determine if reprogramming or applying a magnet is required  Synch shock wave to R wave decrease risk of arrhythmia 8/12/2008 Don Daniels COL MC 14 ESWL  Immersion initially causes vasodilation • Redistribution centrally causes a rise in SVR, leading to decrease in C.O. • Sudden increase in venous return and SVR may trigger CHF in pt w marginal cardiac reserve  Increase in intrathoracic blood volume reduces FRC (30-60%) • Predisposes some pts to hypoxia 8/12/2008 Don Daniels COL MC 15 ESWL  Water bath requires painful high intensity shocks that is not tolerated without GETA or neuraxial anesthesia  Lower energy units that require a small amount of mineral oil to skin utilize lower intensity shock waves allowing light sedation 8/12/2008 Don Daniels COL MC 16 ESWL  T6 epidural adequate for water bath ESWL • Avoid air during LOR technique • Foam tape should not be used, shown to dissipate energy causing damage • Supplemental O2 • Major disadvantage is inability to control diaphragmatic excursion during spont vent • Bradycardia prolongs procedure when shock waves are timed with ECG 8/12/2008 Don Daniels COL MC 17 ESWL  General Anesthesia • Controls diaphragmatic excursion  Sedation for low energy lithotripsy • Low dose propofol with midazolam and narcotic 8/12/2008 Don Daniels COL MC 18 ESWL Monitoring  Apply EKG pads with water proof dressing  Oxygen concentration should be monitored as FRC decrease put patient at increase hypoxia risk  Temperature of bath should be monitored to prevent patient hypo or hyperthermia 8/12/2008 Don Daniels COL MC 19 ESWL fluid management  Generous fluid administration  Bolus with 1000 ml before neuraxial or GETA  Addition 1000-2000 ml given with 10-20 mg lasix to maintain brisk urinary flow to flush stone 8/12/2008 Don Daniels COL MC 20 Surgery on the Upper Ureter & Kidney  Major issue related lateral flexed position changes  Elevation kidney rest compresses vena cava  Venous pooling in legs also decrease venous return  Pneumothorax risk 8/12/2008 Don Daniels COL MC 21  Functional residual capacity Laparoscopic Pelvic Lymph Node Dissection  Steep Trendelenburg  Rotation from side to side for surgical exposure  Potential for greater CO2 absorption  Potential for hypothermia from copious fluid irrigation of clots from pelvic fossa  Usually done under GETA. Most avoid N2O 8/12/2008 Don Daniels COL MC 22 Radical Retropubic Prostatectomy  Requires exaggerated lithotomy  GETA needed due to position and to counter reduction in diaphragmatic excursion  Expect > 2 L blood loss • 2 large bore IV’s • A line monitor 8/12/2008 Don Daniels COL MC 23 Bilateral Orchiectomy  Used to control metastatic adenoca prostrate  Short av 30 min procedure  Can be performed under local, but most prefer GETA 8/12/2008 Don Daniels COL MC 24 Radical Cystectomy  Associated with large blood loss  Incision from pubis to xiphoid • • • • Consider large 3rd space losses Remove bladder, prostrate, seminal vesicles Also take uterus, ovaries, cervix and ant vagina Plus pelvic lymph nodes and urinary diversion  Require at least 4-6 hrs operative time 8/12/2008 Don Daniels COL MC 25 Radical Cystectomy  GETA with relaxation optimal  Controlled hypotension reduces blood loss, transfusion requirement & surgical visualization  Neuraxial anesthesia may induce bowel hyperperistalsis complicating construction of urinary reservoir 8/12/2008 Don Daniels COL MC 26 Radical Cystectomy  A line is indicated  Central line for pts with poor cardiac reserve  PA cath for hx ventricular dysfunction  Forced air warming blanket 8/12/2008 Don Daniels COL MC 27 Urinary diversion Usually follows Radical Cystectomy  Unopposed parasympathetic activity from neuraxial block causes contracted hyperactive bowel  Papaverine 100-150 mg over 2-3 hr, 1 mg gylyopyrrolate or glucagon 1mg may solve contracted bowel problem  Maintain brisk urine, may need CVP to guide IV  8/12/2008 Don Daniels COL MC 28 Testicular Cancer  Initial treatment is radical orchiectomy  Retroperitoneal lymph node dissection used for Rx of nonseminomatous germ cell tumor (Low stage disease)  High stage disease is treated with chemotherapy followed RPLND  Seminomas are primarily rx with retroperitoneal radiotherapy 8/12/2008 Don Daniels COL MC 29 Testicular cancer Chemotherapy  Cisplatin – renal impairment  Vincristine - neuropathy  Vinblastine  Cyclophosphamide  Dactinomycin  Bleomycin – pulmonary fibrosis  etoposide 8/12/2008 Don Daniels COL MC 30 Radical Orchiectomy  Most prefer GETA although regional can be used  Beware of reflex bradycardia from spermatic cord traction 8/12/2008 Don Daniels COL MC 31 Retroperitoneal Lymph Node Dissection (RPLND)  Large incision, evaporative losses  Prior bleo sensitive to oxygen toxicity and fluid overload  Use lowest O2 concentration to keep >90% SpO2  N2O may cause bone marrow suppression  Beware of IVC retraction 8/12/2008 Don Daniels COL MC 32 Renal Cancer  Associated paraneoplastic syndromes’ • • • • Erythrocytosis Hypercalcemia HTN Hepatic dysfunction  5-10%, tumor extends to renal vein & IVC 8/12/2008 Don Daniels COL MC 33 Radical Nephrectomy  General anesthesia  Potential for large blood loss  IVC retraction potential for hypotension  A line indicated, CVP also indicated  Mannitol should be given before incision 8/12/2008 Don Daniels COL MC 34 Rad Nephrectomy & tumor thrombus excision  Thoracoabdominal approach for thrombus extending into IVC  Cardiopulmonary bypass  Aline, PA monitoring  TEE useful to define extent of thrombus  Multiple large bore IV access  >15 units blood not unusual 8/12/2008 Don Daniels COL MC 35 Renal Transplantation  Dialysis should be done before  K should be below 5.5 mEq/L  Correct existing coagulopathies  Heparin before clamping iliac vessels  Verapamil injected intrarterial in graft kidney  Mannitol to promote osmotic diuresis 8/12/2008 Don Daniels COL MC 36 Renal Transplantation  Most done with GETA • Should avoid sevo, ethrane & methoxyflurane • Atracurium or rocuronium are not dependent on renal elimination  Central line helps to ensure hydration  Normal saline or ½ normal  Monitor electrolytes, hyperK may occur due to release of graft preservative Don Daniels COL MC 8/12/2008 37