ANAESTHETIC MANAGEMENT OF ENDOSCOPIC UROLOGIC
PROCEDURES
DR. RICHA JAIN
University College of Medical Science & GTB Hospital, Delhi
ENDOSCOPIC UROLOGIC PROCEDURES
Endoscopic urologic procedures are performed on kidneys, ureters, urinary bladder, prostate, urethra.
CYSTOSCOPY URETEROSCOPY TRANSURETHRAL RESECTION OF BLADDER
TUMOUR (TURBT) TRANSURETHRAL RESECTION OF PROSTATE
(TURP) PERCUTANEOUS NEPHROLITHOTRIPSY ( PCNL)
ANATOMIC CONSIDERATIONS
The sensory nerve supply to genitourinary organs is primarily thoracolumbar and sacral outflow thus, well adapted for regional anesthesia.
PAIN CONDUCTION PATHWAYS
ORGAN SYMPATHETIC PARASYMPATHETIC SPINAL LEVEL OF PAIN CONDUCTION
KIDNEY T8 – L1 CN X (VAGUS) T10 – L1
URETER T10 – L2 S2 – S4 T10 – L2
BLADDER T11 – L2 S2 – S4 T11 – L2(DOME)S2 – S4(NECK)
PROSTATE T11 – L2 S2 – S4 S2 – S4
PENIS L1, L2 S2 – S4 S2 – S4
CYSTOSCOPY The most common urologic
procedure Indications
• Diagnostic Hematuria Recurrent urinary infections Urinary obstruction Bladder biopsies Retrograde pyelograms
• Therapeutic Resection of bladder tumors, Extraction or laser lithotripsy of
renal stones, Placement or manipulation of
ureteral catheters (stents) .
ANAESTHETIC MANAGEMENT
Varies with age, the indication of the procedure and patient preference General anesthesia - children. Topical anesthesia with or without sedation – diagnostic studies. Regional or general anesthesia – operative cystoscopies.
TURBT
For diagnosing and treating bladder cancers PROCEDURE
o Patient laid in lithotomy position.o Cystoscope or resectoscope is introduced into
the bladder.o The tumor is identified & resected.o Coagulating current is used to cauterize the base
of the tumor.o Typical duration of procedure: around 1 h.
ANAESTHETIC CONSIDERSTIONS
Preoperative Considerations Bladder tumor is usually seen in older populations
who may have pre-existing medical problems. Pt may have hematuria, urinary infection.
Intraoperative Concerns Lithotomy positioning Bladder perforation. Bleeding. Obturator reflex.
Stimulation of the obturator nerve by electrocautery may cause the thigh muscles to contract violently, leading to bladder perforation.
This reflex may be eliminated by blocking neuromuscular transmission using a muscle relaxant during GA or by obturator nerve block.
TURBT – CHOICE OF ANAESTHESIA
Anaesthetic technique – regional or general anesthesia.
Neuraxial regional block preferred. Anaesthetic level to T10 is required. GA is indicated when patient requires ventilatory or
haemodynamic support.
TURP - INTRODUCTION
The current gold standard surgical treatment for benign prostatic hyperplasia (BPH).
TURP is the 2nd most common procedure in men over 65 yrs of age.
BPH affects 50% of males at 60 years and 90% of 85-year-olds, so TURP is most commonly performed on elderly patients, a population group with a high incidence of cardiac, respiratory and renal disease.
TURP carries unique complications because of the need to use large volumes of irrigating fluid for the endoscopic resection.
ANATOMY OF PROSTATE
LOCATION: in the pelvis, below neck of urinary bladder
SHAPE : inverted cone SIZE : 4x3x2 cm Weight : 8 gm 5 LOBES:
BPH – median, anterior, 2 lateral Prostatic carcinoma – posterior,
lateral Composed of glandular tissue in
fibromuscular stroma. 2 capsules:
True – formed by condensation of prostatic tissue
False – formed by visceral layers of pelvic fascia.
ANATOMY OF PROSTATE
Sympathetic supply T11-L2 Inferior hypogastric
plexus Parasympathetic
supply S2,3,4 Pelvic splanchnic
nerve
Arterial supply Inferior vesical artery Middle rectal artery Internal pudendal
artery Venous supply
Vesical plexus Internal pudendal
veins Vertebral venous
plexus
NERVE SUPPLY BLOOD SUPPLY
TURP - PROCEDURE
Performed in the lithotomy position using a resectoscope, through which a diathermy loop is passed.
The prostatic tissue is resected in small strips under direct vision using the diathermy loop.
The bladder is continuously irrigated with fluid.
At end of the procedure, a three-lumen catheter is inserted and irrigation is continued for up to 24 h after operation.
The procedure usually takes 30–90 min.
IRRIGATION FLUIDS
Characteristics of Ideal irrigation fluid:1. Transparent2. Isotonic3. Electrically inert4. Non hemolytic5. Inexpensive6. Not metabolizable7. Rapidly excretable8. Non toxic9. Easy to sterilise
Uses distends bladder and
prostatic urethra flushes out blood
and tissue debris improves visibility
SOLUTION OSMOLALITY (mOsm/kg)
ADVANTAGES DISADVANTAGES
DISTILLED WATER
0 (hypo) Electrically inertImproved visibilityInexpensive
HemolysisHemoglobinuriaHemoglobinemiaHyponatremia
GLYCINE (1.5%) GLYCINE (1.2%)
220 (iso)
175 (hypo)
Less likelihood of TURP syndrome
Transient postoperative visual syndrome,Hyperammonemia,Hyperoxaluria
NORMAL SALINE (0.9%)
308 (iso) Less incidence of TURP syndrome
Ionized, cannot be used with cautery
RINGER LACTATE
273 (iso) Ionized, cannot be used with cautery
SOLUTION OSMOLALITY (mOsm/kg)
ADVANTAGES DISADVANTAGES
MANNITOL (5%)
275 (iso) Isomolar solutionNot metabolized
Osmotic diuresis, Acute intravascular expansion
SORBITOL (3.5%)
165 (hypo) Same as glycine
Hyperglycemia, Lactic acidosisOsmotic diuresis
GLUCOSE (2.5%)
139 (hypo) Hyperglycemia
UREA (1%)
167 (hypo) Increases blood urea
CYTAL(sorbitol 2.7% +mannitol 0.54%)
178 (iso) Expensive, not easily available
FACTORS AFFECTING AMOUNT AND RATE OF FLUID ABSORPTION
Size of gland (25ml/gm of prostate) Number and size of open sinuses Hydrostatic pressure of irrigating fluid Duration of procedure (@ 20-30 ml/min) Integrity of capsule Venous pressure at irrigant-blood interface Vascularity of diseased prostate
PREOPERATIVE CONSIDERATIONS
Patients for TURP are frequently elderly with coexistent diseases.
- cardiac disease 67%
- cardiovascular disease 50%
- abnormal electrocardiogram (ECG) 77%
- chronic obstructive pulmonary disease 29%
- diabetes mellitus 8%
Occasionally, patients are dehydrated and depleted of essential electrolytes (long-term diuretic therapy and restricted fluid intake).
Long standing urinary obstruction can lead to impaired renal function and chronic urinary infection.
About 30% of TURP patients have infected urine preoperatively
PREOPERATIVE EVALUATION
History and examination of all organ systems
INVESTIGATIONS Hb, TLC, DLC, platelet count Blood sugar Blood urea, S. Creatinine, S. Electrolytes Urine R/M ECG Chest X-ray Blood grouping and cross matching
PREOPERATIVE PREPARATION
Optimization of pre-existing co-morbid conditions
Consideration of ongoing drug therapy Antibiotic prophylaxis (in case of urinary tract
infection or urinary obstruction) Arrangement of blood
CHOICE OF ANAESTHESIA
Regional anaesthesia is the technique of choice for TURP.
Advantages of regional over general anaesthesia1. Allows monitoring of mentation and early signs of TURP
syndrome and bladder perforation2. Promotes peripheral vasodilation , reducing circulatory
overload 3. Reduces blood loss, requiring fewer transfusions4. Avoids effects of general anaesthesia on pulmonary pathology5. Good early post-operative analgesia6. Reduced incidence of post-operative DVT/PE7. Neuroendocrine and immune response are better preserved8. Lower cost
General anaesthesia preferred when regional is contraindicated.
REGIONAL ANAESTHESIA
TECHNIQUES: Subarachnoid block Epidural block Caudal block Saddle block
Level of sensory block T10 dermatome level – to eliminate discomfort
caused by bladder distention T9 dermatome level – enable to elicit capsular
sign (pain on perforation of prostatic capsule)
REGIONAL ANAESTHESIA
Subarachnoid block is preferred. Advantages of SAB over epidural
anaesthesia: Technically easier to perform Dense motor blockade No sacral sparing Lower incidence of PDPH
MONITORING
ECG Blood pressure Pulse oximetry Temperature Mentation Blood loss S. electrolytes (serial) EtCO2 if GA is used
INTRAOPERATIVE CONSIDERATIONS
Lithotomy position TURP syndrome Bladder perforation Hypothermia Transient bacterial
septicemia Hemorrhage and
coagulopathyMain challenges: blood loss and TURP syndrome
LITHOTOMY POSITIONING
Both lower limbs raised together, flexing the hips and knees simultaneously.
Ensure proper padding at edges and angulations.
While lowering, legs brought together at knees and then lowered slowly to prevent stress on spine and sudden fall in BP.
LITHOTOMY POSITIONING
Physiologic changes with lithotomy Decreased FRC Increased venous
return on elevation of legs
Decreased venous return following lowering of legs
Exaggeration of hypotension with SAB
Problems with lithotomy position Injury to nerves Injury to fingers Compression of major
vessels at joints Lower extremity
Compartment syndrome Aggravation of
preexisting lower back pain
TURP SYNDROME
Rapid absorption of a large-volume irrigation solution. Can occur 15 min after resection or upto 24 hrs
postop. Incidence : 1 – 8% Characterized by intravascular volume shifts and
plasma-solute (osmolarity) effects: Circulatory overload Water intoxication Hyponatremia Hypoosmolality Hyperglycinemia Hyperammonemia Hemolysis
TURP SYNDROME – WATER INTOXICATION
Cause : cerebral edema Signs and symp:
Somnolence, restlessness, seizures, comaCNS – decerebrate posture, clonus, +ve
babinski’s reflexEyes – papilloedema, dilated and non
reactive pupilsEEG – low voltage b/l.
TURP SYNDROME - HYPONATREMIA
Cause : excessive absorption of Na free irrigation fluid
During TURP, S.Na falls by 3 to 10 meq/l. SIGNS AND SYMPTOMS OF Acute Hyponatremia
Nausea Vomiting Irritability Mental confusion Cardiovascular collapse Pulmonay edema Seizures
MANIFESTATIONS OF HYPONATREMIA
SERUM Na+ (mEq/l)
CNS changes
CVS changes
ECG Changes
120 ConfusionRestlessness
Hypotension bradycardia
wide QRS complex
115 SomnolenceNausea
Cardiac depression
Bradycardia Wide QRS complexElevated ST segment
110 Seizures Coma
CHF Ventricular tachycardia or fibrillation
TURP SYNDROME - HYPERGLYCINEMIA
Glycine, a non essential amino acid, is an inhibitory neurotransmitter in spinal cord and retina.
Metabolized in liver by oxidative deamination to ammonia and glyoxylic and oxalic acid.
When absorbed in large amounts, has direct toxic effects on heart and retina.
Manifestations of glycine toxcity: nausea, headache, malaise, weakness, visual distubances ( transient blindness), seizures, encephalopathy.
TURP SYNDROME - HYPERAMMONEMIA
Excessive absorption of glycine may lead to hyperammonemia (blood NH3> 500mmol/L).
S/S: nausea, vomiting, comatose for 10-12 hrs and awakens when blood NH3 < 150 mmol/L.
Explanation : arginine deficiency
TURP SYNDROME – CLINICAL FEATURES System Signs and Symptoms Cause
Neurologic Nausea, restlessness, visual disturbances, confusion, somnolence, seizures,coma,death
Hyponatremia and hypoosmolality Hyperglycinemia Hyperammonemia
Cardiovascular
Hypertension, reflex bradycardia, pulmonary edema, CVS collapseHypotension ECG changes(wide QRS, elevated ST segments, vent arrhythmia)
Rapid fluid absorption
Third spacingHyponatremia
Respiratory Tachypnea, oxygen desaturation, cheyne- stokes breathing
Pulmonary edema
Hematologic Disseminated intravascular hemolysis
Hyponatremia and hypoosmolality
Renal Renal failure Hypotension, hemolysis, hyperoxaluria
Metabolic Acidosis Deamination of glycine
MEASUREMENT OF FLUID ABSORPTON
1. Volume absorbed = (preoperative Na+/ postoperative Na+ ) ECF - ECF
2. Volumetric fluid balance (diff. b/w amt of irrigation fluid used and volume recovered.)
3. Gravimetry (measure rise in body weight)4. CVP monitoring5. Breath ethanol measurement6. Isotopes
TURP SYNDROME - PREVENTION
Early diagnosis and prompt treatment Correction of fluid and electrolyte
abnormalities preoperatively Cautious adminstration of IV fluids Limitation of hydrostatic pressure of irrigation
fluid to 60cm Restrict duration of TURP to 1 hr Bipolar resectoscope Vaporization methods Local vasoconstrictors
TURP SYNDROME - MANAGEMENT Notify surgeon and terminate surgery. Ensure oxygenation Restrict fluids Pulmonary edema : intubate and IPPV Bradycardia, hypotension: atropine, adrenergic
agents Seizures : BZD, thiopentone, phenytoin, i.v.Mg2+
Invasive monitoring of arterial and CVP Send blood sample for electrolytes, arterial blood gas
analysis.
TURP SYNDROME - MANAGEMENT
Treat mild symptoms (if S. Na+ > 120 mEq/L) with fluid restriction and loop diuretic (furosemide)
Treat severe symptoms (if S. Na+ <120 mEq/L) with 3% NaCl IV at rate < 100 ml/ hr.
BLADDER PERFORATION Incidence – 1% Causes
Trauma by surgical instrument Overdistention of bladder with irrigation fluid
Manifestation Early sign : sudden decrease in return of irrigation
solution from bladder Extraperitoneal perforations : pain in periumbilical,
inguinal or suprapubic region Intraperitoneal : generalised abdominal pain, shoulder
tip pain, abdo rigidity
BLOOD LOSS
Difficult to quantify blood loss. Visual estimation of haemorrhage may be difficult due
to dilution with irrigation fluid. Usual warning signs (tachycardia, hypotension)
masked by overhydration and effects of regional anaesthesia.
Blood loss can be estimated on the basis of Resection time (2-5ml/min) Size of prostate (7-20ml/g) No. of open venous sinuses
Intraoperative BT should be based on preop Hb, duration and difficulty of resection and clinical assessment of pt condition.
COAGULOPATHY
Causes of excessive bleeding Dilutional thrombocytopenia DIC as a result of release of prostatic particles
rich in thromboplastin into blood Local release of fibrinolytic agents (plasminogen
and urokinase)
Treatment – administration of FFP, platelets blood transfusion
HYPOTHERMIA
Continuous fluid irrigation causes loss of temp @1oC/hr.
Elderly patients have reduced thermoregulatory capacity. Unintentional hypothermia is asso. with a significantly
higher incidence of postoperative MI. Postoperative shivering asso. with hypothermia may
dislodge clots and promote postoperative bleeding.
Monitor body temp of patient to maintain normothermia. Appropriate measures to reduce heat loss are: warming
blankets, heated irrigation solution and warm I/V fluids.
BACTEREMIA AND SEPTICEMIA
INCIDENCE – 6-7% Causes
Release of bacteria from prostatic tissue Preoperative indwelling urinary catheter Preoperative UTI
C/F – chills, fever, tachycardia T/T – antibiotic, supportive care
POSTOPERATIVE COMPLICATIONS
Hypothermia Hypotension Haemorrhage Septicaemia TURP syndrome Bladder spasm Clot retention Deep vein thrombosis Postoperative cognitive impairment
PERCUTANEOUS NEPHROLITHOTOMY
The procedure of choice for removing complex and large renal stones.
Imp. Indications of PCNL : Stone size >/= 2.5 cm. Stones resistant to ESWL Staghorn stones in lower calyx
Advantages of percutaneous method Lower morbidity and mortality Faster convalescence Small incision Minimum operative and postoperative complications.
ANATOMICAL CONSIDERATIONS
Kidneys are retroperitoneal organs, located in paravertebral gutters.
Right kidney lies adjacent to 12th rib, liver, duodenum and hepatic flexure of colon.
Left kidney is related to 11th and 12th ribs, stomach, pancreas, spleen and splenic flexure of colon.
Superior pole in direct contact with diaphragm.
PCNL : PROCEDURE
PCNL consists of gaining percutaneous access to the kidney collecting system and performing stone disintegration, usually with ultrasonic or pneumatic lithotripters.
PERCUTANEOUS APPROACHES
Subcostal /Intercostal approach Intercostal puncture is made
over lateral portion of rib but medial to viscera during expiration
INTRAOPERATIVE COMPLICATIONS
HAEMORRHAGE
INJURY TO RENAL PELVIS
FLUID ABSORPTION
INJURY TO PLEURA
INJURY TO ADJACENT ORGANS
SEPTICEMIA
ANAESTHETIC TECHNIQUE
PCNL can be performed under general or regional anesthesia.
General anesthesia is preferred. Patient is laid in prone/ lateral oblique position.
ANAESTHETIC CONSIDERATIONS
POSITION - Prone / lateral oblique position
INTRATHORACIC COMPLICATIONS• Most often injured organ during PCNL : lung and
pleura.• Risk of injury increases with more superior punctures.
Approach Incidence
Subcostal 0.5%
Supra-12th rib 1.5 – 12%
Supra – 11th rib 23.1%
ANAESTHETIC CONSIDERATIONS• Close coordination of percutaneous access
puncture and tract dilation with respiration is essential to minimise pleural injury.
• Monitoring of airway pressure, ETCO2 , SpO2 required.
• Fluoroscopic monitoring of chest during procedure is a sensitive means of timely diagnosis of pneumothorax or hydrothorax.
• A chest X-Ray recommended in the recovery room.
ANAESTHETIC CONSIDERATIONS
Acute anemia due to blood loss or hemodilution . Repeat Hb measurement should be considered in the
perioperative period.
Fluid absorption due to high pressure fluid irrigation in presence of
venous injury or collecting system perforation. Can lead to hypothermia, TURP syndrome, sepsis.
ANAESTHETIC CONSIDERATIONS
Hypothermia due to large amount of fluids administered for
irrigation. Causes shivering, peripheral vasoconstriction
and delayed drug clearance. Prevention by use of warmed intravenous and
irrigation fluids.
Septicemia All patients have urine cultures done
preoperatively with administration of an appropriate antibiotic
REFERENCES
Miller’s Anesthesia 7th Editon. Anesthesia and renal and genitourinary system.
Barasch’s Clinical Anesthesia 5th Edition. The renal system and anesthesia for urologic surgery.
Yao and Artusio’s Anesthesiology problem oriented patient management. 6th Edition.
Clinical anesthesiology by Morgan and Mikhail. 4th Edition. Anesthesia for genitourinary surgery.
Vsevold Rozentsveig. Anesthetic considerations during percutaneus nephrolithotomy. Journal of Clinical Anesthesia 2007:19,351-355.
Dietrich Gravenstein. Transurethral resection of prostate (TURP) syndrome: a review of pathophysiology and management. Anesth Analg 1997;84:438-46.