Transcript anesthesia for turp,turbt and nephrectomy

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