ANESTHESIA FOR TURP, TURBT AND NEPHRECTOMY MODERATED BY-DR GIRISH PRESENTED BY-DR CHITTRA ANESTHESIA FOR TURP AND TURBT WHAT IS TURP!!!!!! TURP is resecting prostatic tissue with an electrically powered cutting-coagulating metal loop performed by inserting a resectoscope through the urethra As much prostatic tissue as possible is resected, but the prostatic capsule is usually preserved An irrigating solution flows into surgical site to distend bladder and to bathe surgical site washing away blood and debris removed by wire loop ANATOMY The prostate is a fibromuscular glandular organ that surrounds the prostatic urethra It is about 1.25 in. (3 cm) long and lies between the neck of the bladder above and the urogenital diaphragm below The prostate is divided into five lobes The anterior lobe lies in front of the urethra and is devoid of glandular tissue The median lobe is situated between the urethra and the ejaculatory duct The posterior lobe is situated behind the urethra and below the ejaculatory ducts and also contains glandular tissue The right and left lateral lobes lie on either side of the urethra and are separated from one another by a shallow vertical groove on the posterior surface of the prostate ARTERIAL SUPPLY Branches of the inferior vesical and middle rectal arteries VENOUS SUPPLY Veins form the prostatic venous plexus, which lies outside the capsule of the prostate LYMPHATIC DRAINAGE Internal iliac nodes NERVE SUPPLY Inferior hypogastric plexuses The average age of patients currently undergoing TURP is approximately 69 years,and the average amount of prostate tissue resected is 22 g Risk factors associated with increased morbidity prostate glands larger than 45 g operative time longer than 90 min acute urinary retention as presenting symptom AGE RELATED PHYSIOLOGICALCHANGES CENTRAL NERVOUS SYSTEM Decreased fxnl neuronal tissue Sluggish or impaired reflex responses Reduced ability to generate body temp Reduction in the area of the epidural space Increased permeability of dura Decreased volume of cerebrospinal fluid PERIPHERAL NERVOUS SYSTEM Diameter and number of myelinated fibers in dorsal and ventral nerve roots are decreased Decrease in inter–Schwann cell distance conduction velocity CARDIOVASCULAR SYSTEM Decreased contractility, increased myocardial stiffness , ventricular filling pressures, and decreased β-adrenergic sensitivity Impaired baroreceptor function RESPIRATORY SYSTEM Decreased alveolar surface area,diffusion capacity,lung elasticity,mechanical ventilation reserve Ventilatory responses to hypoxia, hypercapnia, and mechanical stress are impaired secondary to reduced central nervous system activity RENAL FUNCTION Renal blood flow decrease about 10% per decade Progressive decline in creatinine clearance with age Renal capacity to conserve sodium is decreased At risk for dehydration and sodium depletion Prolongation of plasma half life of drugs PREOP EVALUATION AND PREPARATION Routine history and physical examination Special attention to CVS and respiratory system Because of their age these patients have relatively high (30–60%) prevalence of both cardiovascular and pulmonary disorders Beta-blockers suppress the compensatory tachycardic response to hypotension associated with SAB or haemorrhage Alpha blockers-The combined hypotensive effects of these drugs may precipitate severe hypotension after SAB Aspirin-stopped minimum 7 days before surgery Warfarin- If the INR is greater than 1.4 the procedure should be postponed until the INR is acceptable Clotting studies Blood should be available and crossmatched POSITIONING OF PATIENT Hips are flexed 80 to 100 degrees from trunk, and legs are abducted 30 to 45 degrees from the midline Knees are flexed until the lower legs are parallel to torso and legs are held by supports or stirrups The foot section of the operating room table is lowered Positioning the arms on armrests far from the table hinge point is recommended at all times when patients are in the lithotomy position Initiation of the lithotomy position requires coordinated positioning of the lower extremities by two assistants to avoid torsion of the lumbar spine Both legs should be raised together flexing the hips and knees simultaneously The lower extremities should be padded to prevent compression against the stirrups Injury to the common peroneal nerve, resulting in loss of dorsiflexion of the foot may result if the lateral thigh rests on the strap support If legs are allowed to rest on medially placed strap supports, compression of the saphenous nerve can result in numbness along the medial calf Excessive flexion of thigh against the groin can injure obturator nerve and femoral nerve Extreme flexion at thigh can also stretch the sciatic nerve PHYSIOLOGICAL ALTERATIONS Preload increases, causing a transient increase in cardiac output may exacerbate congestive heart failure. cerebral venous and intracranial pressure may increase diaphragm becomes cephalad, reducing lung compliance ,FRC and predisposing patient to atelactasis and hypoxia If obesity or a large abdominal mass is present abdominal pressure may increase significantly enough to obstruct venous return to the heart Normal lordotic curvature of the lumbar spine is lost in the lithotomy position, potentially aggravating any previous lower back pain ANESTHETIC TECHNIQUES REGIONAL ANESTHESIA Spinal anesthesia is the most frequently used anesthetic for TURP and is believed to be the technique of choice Satisfactory anesthesia for TURP involves achieving an anesthetic block level that interrupts sensory transmission from the prostate and bladder neck Regional anesthesia resulting in a sensory level to T10 is required to eliminate the discomfort caused by bladder distention Spinal anesthesia provides adequate anesthesia for the patient and good relaxation of the pelvic floor and the perineum Signs and symptoms of water intoxication and fluid overload can be recognized early because the patient is awake. Accidental bladder perforation also is recognized easily if the spinal level is limited to T10 because the patient would experience abdominal or shoulder pain. Subarachnoid anesthesia is generally preferred over continuous epidural anesthesia It is technically easier to perform in elderly patients and the duration of surgery is generally not very long o CAUDAL ANESTHESIA has been used effectively in high-risk patients undergoing laser prostatectomy o Hemodynamic stability is the main advantage with this technique. GENERAL ANESTHESIA o Who require ventilatory or hemodynamic support o Have a contraindication to regional anesthesia o or refuse regional anesthesia. INTRAOP MONITORING ECG Blood pressure Temperature Pulse oximetry End tidal CO2 CVP Line ADVANTAGES OF REGIONAL ANESTHESIA Amount of blood loss is reduced Less chances of DVT monitoring the patient's mental status intraoperatively Bladder perforation is recognized earlier in a conscious patient decreased requirement for analgesics in the immediate postoperative period COMPLICATIONS OF TURP ABSORPTION OF IRRIGATION FLUID/TURP SYNDROME Height of irrigating fluid > 60cm above operating field Time of resection >1hr 10 to 30 mL of fluid is absorbed per minute of resection time Vascularity of diseased prostate {(Preop Na÷post op Na)× ECF}-ECF Dilutional hyponatraemia-Encephalopathy and seizures may develop when the sodium concentration falls below 120mmol/l Fluid overload- causes pulmonary oedema and cardiac failure Glycine toxicity- causes depression of the level of consciousness and visual impairment at toxic levels SIGN AND SYMPTOMS Tachycardia Nausea and vomiting Confusion / disorientation Hypertension (fluid overload) then hypotension Transient blindness Angina Dyspnoea and hypoxia Cardiovascular collapse and arrhythmias Convulsions ,coma If the patient is under general anaesthesia all of the symptoms and some of the signs are masked and only unexplained tachycardia and hypotension may be present. Increase risk of TURP syndrome Pre-existing hyponatraemia or pulmonary oedema Prostate size larger than 60-100g Inexperienced or slow surgeon Procedures longer than 1 hour Hydrostatic pressure > 60cm H20 Use of large volumes of hypotonic intravenous fluids like 5% dextrose MANAGEMENT ABC Algorithm terminate surgery as soon as bleeding points have been coagulated stop IV fluids and commence fluid restriction frusemide 40mg IV Hypertonic saline solutions 1.8%, 3% or 5% should be used to increase the serum sodium level by about 1 mmol/l/hour, not exceding an increase of 20mmol/l in the first 48 hours of therapy Convulsions should be acutely treated with a benzodiazepine or small doses of thiopentone In presence of intractable seizures, the sodium level may be corrected more rapidly at a rate of up to 8-10mmol/l/hour for the first 4 hours of therapy . IRRIGATION FLUIDS IDEAL….. Non-electrolytic Non-toxic Transparent Non-metabolizable Rapidly excreatable Inexpensive Isosmolar and non- hemolytic GLYCINE Glycine-1.2% 175 mosm/kg Glycine-1.5% 220 mosm/kg Metabolizes to ammonia ,water and glycolic acid Hyperammonemia and water intoxication can lead to cerebral edema and seizures SORBITOL 3.5% 165mosm/kg Metabolizes to CO2,H2O and glucose MANNITOL 5% 275mosm/kg Dehydration and hyperosmolality CYTAL Sorbitol 2.7%, and mannitol 0.54% GLUCOSE 2.5% 139mosm/kg Leaves surgical site and instruments very sticky Elevated serum glucose levels UREA 1% 167mosm/kg Permeable to intracellular and extracellular Nausea,vomiting,headache,tachycardia,di minished vision,convulsions and coma Osmotic diuretic effect SALINE AND RL SOLUTION These electrolyte solutions are highly ionized and facilitate the dispersion of high-frequency current from a monopolar resectoscope GLYCINE TOXICITY Glycine is a major inhibitory transmitter acting in the spinal cord and brainstem Retinal toxicity and blindness Might be associated with myocardial depression and hemodynamic changes associated with TURP syndrome AMMONIA TOXICITY CNS toxicity may occur as a result of oxidative biotransformation of glycine to ammonia Deterioration of CNS function is said to occur when ammonia levels are greater than 150 M BLADDER PERFORATION If extraperitoneal pain in the periumbilical, inguinal or suprapubic regions and irregular return of irrigating fluid If intraperitoneal pain may be generalized in the upper part of the abdomen or referred from the diaphragm to precordial region or shoulder HYPOTHERMIA Heat loss as a result of irrigation and significant absorption of fluid may lead to a decrease in the patient's body temperature and cause shivering Warmed irrigating solutions are efficacious in reducing heat loss and the resultant shivering BLOOD LOSS A hypertrophied prostate is highly vascular Blood is washed into the draining bucket and mixed with ample quantities of irrigant fluid Estimation of blood loss is inaccurate and extremely difficult Blood loss based on resection time- 2 to 5 mL/min size of the prostate in grams -20 to 50 mL/g patient's vital signs should be monitored to assess better for the blood loss and need for transfusion OBTURATOR REFLEX o The obturator nerve runs near the prostate and can be electrically stimulated during transurethral prostate surgery, causing a violent thrusting of the leg o This reflex can possibly lead to inadvertent intraoperative surgical complications o The problem of unintentional obturator nerve stimulation can be corrected under general anesthesia by paralyzing the patient o The obturator reflex most often occurs while resecting bladder tumors on the lateral walls of the bladder o LA injection into sensitive area ANESTHESIA FOR NEPHRECTOMY ANATOMICAL DETAILS The right kidney lies slightly lower than the left kidney During respiration, both kidneys move downward in a vertical direction by as much as 1 inch On the medial concave border of each kidney there is a structure called the hilum The hilum transmits, from front backward, the renal vein, two branches of renal artery and ureter ARTERIAL SUPPLY The renal artery arises from aorta at the level of the second lumbar vertebra Each renal artery usually divides into five segmental arteries that enter the hilum of the kidney Lobar arteries –interlobar-arcuateinterlobular-afferent glomerular VENOUS SUPPLY Renal vein emerges from the hilum in front of the renal artery and drains into the inferior vena cava. NERVE SUPPLY Sympathetic nerves to the kidney originate as preganglionic fibers from the T8 to L1 and converge at the celiac plexus and aorticorenal ganglia Parasympathetic input is from the vagus nerve Effective neural block of these segments is necessary to provide adequate analgesia or anesthesia. PREOP ASSESMENT AND EVALUATION Routine history and examination Renal function tests and BP Serum electrolytes All baseline investigations Blood should be arranged ANESTHESIA General anesthesia POSIOTIONING OF PATIENT The patient's head must be kept in a neutral position to prevent excessive lateral rotation of the neck and stretch injuries to the brachial plexus The dependent ear should be checked to avoid folding and undue pressure Eyes should be securely taped before repositioning if the patient is asleep The dependent eye must be checked frequently for external compression an axillary roll is frequently placed just caudal to the dependent axilla never be placed in the axilla weight of thorax is borne by the chest wall caudal to the axilla and avoid compression of the axillary contents pulse should be monitored in the dependent arm consistently When a kidney rest is used, it must be properly placed under the dependent iliac crest to prevent compression of the inferior vena cava Padding is generally placed between the knees with the dependent leg flexed to minimize excessive pressure on bony prominences and any stretch on low extremity nerves Combination of lateral weight of the mediastinum and disproportionate cephalad pressure of abdominal contents on the dependent lung favors overventilation of the nondependent lung Also pulmonary blood flow to underventilated, dependent lung increases owing to the effect of gravity Consequently, ventilation-perfusion matching worsens potentially affecting gas exchange and ventilation. RADICAL NEPHRECTOMY FOR TUMORS ANESTHETIC IMPLICATIONS 85%-90% are for renal cell cancer 5%-10% extension to the IVC and right atrium Large-bore IV access, A-line, IJV line Hypercalcemia, increased prolactin, erythropoietin, glucocorticoids Associated comorbidities extent of the lesion must be defined preoperatively CVP catheter inserted through left IJV or external jugular vein so as not to place it beyond the superior vena cava Cardiopulmonary bypass is often required in these cases to prevent tumor embolization, and necessary with tumor thrombus extension into the upper portion of the hepatic vena cava decrease in venous return also predisposes the patient to hypotension during induction of anesthesia All approaches are painful-epidurals are useful but need to cover up T7/8 for loin incision NSAIDS are useful if renal fxn is good postoperatively