Radical prostatectomy

Yanhong Liu, M.D., Ph.D.; William R. Kimball, M.D., Ph.D.; Yandong Jiang M.D., Ph.D.

What the Anesthesiologist Should Know before the Operative Procedure

Different from simple prostatectomy, which is done mainly for the treatment of prostate enlargement (benign prostatic hyperplasia), radical prostatectomy is the treatment of choice for localized prostate cancer. As the fourth most common male malignant neoplasm worldwide, prostate cancer is probably affecting an estimated 189,000 men in the U.S. each year. However, not all patients with prostate cancer will receive radical prostatectomy. In fact, radical prostatectomy is indicated only in patients with early stage cancer and having at least a 10-year life expectancy and low co-morbidities. Many elderly men adopt a policy of “watchful waiting,” especially if their cancer is growing slowly. For those with prostate cancer metastasis, radical prostatectomy will not prevent the remaining cancer from growing and spreading throughout the body. Despite of other alternative treatment, there are about 90,000 radical prostatectomy performed in the U.S. each year.

Surgical approaches for radical prostatectomy include traditional open prostatectomy and minimally invasive surgical procedure. Minimally invasive surgical procedures have recently gained popularity due to the advantages of significantly less trauma than conventional open procedures, less postoperative pain, shorter hospital stays, and more rapid return to normal activities. However, a recent study demonstrated comparable functional outcome with open and laparoscopic techniques in a large academic medical institute.

a. Open prostatectomy

Open radical prostatectomy is common, and can be achieved through either a retropubic or a perineal approach, depending on the size and location of the tumor, patient’s body habitus and surgeon’s preference. However, perineal approach has become less common due to limited access to lymph nodes and difficulty in avoiding nerve injuries.

In radical prostatectomy, the entire prostate gland is removed, together with the bladder neck, both seminal vesicals, and the ampullae of the vas deferens. A limited pelvic lymphadenectomy also is performed. After the removal of prostate gland and its associated structures, the urethra is anastomosed directly to the bladder neck over an indwelling Foley catheter.

b. Minimally invasive radical prostatectomy

i. Laparoscopic radical prostatectomy

Laparoscopic radical prostatectomy is a form of minimally invasive surgery performed through small incisions with the use of a two dimensional laparoscope to view the prostate and the surrounding tissues. To access the prostate, both transperitoneal and extraperitoneal approaches can be used. The transperitoneal approach facilitates the lymphadenectomy but carries a higher risk of intestinal and vascular injury, urinary ascites, and postoperative intestinal obstruction. Carbon dioxide is pumped into the surgical site to create space for access to the prostate. The cardiovascular and respiratory effects of pneumoperitoneum and the possibility of marked acidosis due to the absorption of CO2 should be the concerns of anesthesia care providers, particularly for patients with respiratory insufficiency.

ii. Robotic prostatectomy

Over recent years, the introduction and widespread adoption of a robotic surgical system has changed the view on minimally invasive surgery. When performing robotic surgery, the surgeon sits at a console with a three-dimensional view of the operating field and controls the movements of miniature instruments at the end of robotic arms inserted through several small incisions in the body. The movement of the surgeon’s hands is translated into precise movements of the instruments in the surgical area. Early outcomes obtained with this new technique are comparable with laparoscopic and open prostatectomy. However, many studies are retrospective, and there is a lack of long-term follow-up. Scientific justification for the increased cost, prolonged surgical duration, and the morbidity associated with its learning curve during the robotic prostatectomy is still needed.

1. What is the urgency of the surgery?

What is the risk of delay in order to obtain additional preoperative information?

Emergent- Radical prostatectomy is often not emergent. The physicians have time to optimize the patients’ condition before operation.
Urgent- Urgent radical prostatectomy is rarely needed.
Elective- This surgery is never truly elective since radical prostatectomy is often performed for removal of prostate tumors and should be performed as soon as the patient’s condition is optimized. Delay of the procedure may increase the incidence of tumor metastasis and the anxiety of the patient and/or family members.

2. Preoperative evaluation

The average age at diagnosis of prostate cancer is about 65 years. These patients may have pre-existing medical problems, such as cardiovascular and pulmonary disease, diabetes mellitus, renal impairment and other medical conditions. Pre-operative evaluation should be directed toward the identifying and treatment of these conditions prior to surgery.

Medically unstable conditions warranting further evaluation include: Hypertension, coronary artery diseases (CAD), chronic obstructive pulmonary disease (COPD), asthma, cerebrovascular disease, renal impairment, arthritides, diabetes mellitus and other medical problems.
Delaying surgery may be indicated if: recent myocardial infarction, unstable arrhythmias, recent angioplasty with stent placement, stroke, transient ischemic attack (TIA), and COPD or asthma exacerbation exist. These conditions warrant further assessment, consultation, work-up and stabilization.

3. What are the implications of co-existing disease on perioperative care?

a. Cardiovascular system

i. Pre-operative evaluation

i) Acute/unstable conditions – Consider postponing surgery until patient’s cardiac condtion has been optimized.

Hypotension or arrhythmias due to acute myocardial infarction/unstable angina

Severe bradycardia or atrio-ventricular block

Ventricular tachycardia or ventricular fibrillation

If history, physical examination, or clinical suspicion suggest these conditions, a work-up is needed including a 12 lead electrocardiogram, continuous electrocardiogram monitoring, cardiac biomarkers (e.g. troponin), resting echocardiogram (for regional wall motion abnormalities), and cardiac consultation. Acute ischemia needs to be treated prior to surgery. Severe bradycardia or atrioventricular block may require placement of a temporary pacemaker (transcutaneous esophageal or transvenous). Ventricular tachycardia or ventricular fibrillation requires a cardioverter-defibrillator apparatus.

ii) Baseline coronary artery disease or cardiac dysfunction – Hypetension and coronary artery diseases are common in this patient group. It is necessary to obtain a good clinical history (e.g., functional status, changes in exercise tolerance, fatigue), a prior electrocardiogram or non-invasive stress testing, and consultation of the patient’s cardiologist or primary care physician if necessary. Outcome studies do not demonstrate a benefit when pre-operative cardiac testing is performed in intermediate risk patients or patients without signs or symptoms of acute ischemia.

ii. Perioperative risk reduction strategies:

i) Monitoring – Consider placing a pre-induction arterial line. Full perioperative hemodynamic monitoring (e.g., central venous pressure) may also be warranted.

ii) Goals – Optimize the myocardial oxygen supply and demand ratio.

1. Increase O2 supply

FiO2 – Consider using high FiO2 to achieve a SpO2 of 100%.
Hemoglobin – Consider transfusing to increase oxygen carrying capacity in case of substantial blood loss.
Heart rate – Consider reducing heart rate with beta blockers or calcium channel blockers in order to increase diastolic time, as left ventricle perfusion occurs only in diastole.
Coronary perfusion pressure – Optimize coronary perfusion pressure, which equals diastolic pressure minus left ventricular diastolic pressure.
Avoid hypercarbia – Hypercarbia may cause intense sympathetic discharge and a significant increase in plasma catecholamine levels. When PaCO2 levels reach 56 to 65 mmHg, cardiac oxygen demand significantly increases, while coronary filling time is shortened as indicated by the increase in the tension-time index and the decrease in the diastolic time. This signifies a relative myocardial hypoperfusion.

2. Reduce O2 demand

Heart rate – Beta blockers and calcium channel blockers reduce heart rate and oxygen consumption.
Contractility – Beta blockers and calcium channel blockers reduce contractility and O2 demand.
Afterload optimization – Increased afterload (systemic vascular resistance, SVR) raises the resistance against which the heart needs to pump, and hence, myocardial oxygen consumption (i.e., pressure work) increases. However, if afterload is too low, it may jeopardize coronary perfusion pressure.
Preload optimization – Adequate stroke volume without exceeding optimal contractility along the Frank-Starling curve (i.e., avoid increasing pressure work).

b. Pulmonary system:

Patients with pulmonary diseases are at higher risk of postoperative lung dysfunction including pneumonia. Perioperative hypoxia may result from pulmonary emboli, atelectasis, pulmonary congestion (and effusion) due to chronic heart failure, or consolidation due to infection. Additionally, aging leads to higher alveolar-arterial oxygen gradient due to an increase in closing volume and intra-pulmonary shunt.

i. COPD:

i) Pre-operative evaluation: Careful clinical history must be obtained including pack year smoking history, frequency of exacerbations, recent or current exacerbation, oxygen requirement, current medication regimen (e.g., bronchodilators and steroids), and recent studies (e.g., spirometry). Unless acute exacerbation is suspected, pulmonary testing may delay surgery unnecessarily.

ii) Perioperative risk reduction strategies

Continue current pulmonary medications peri-operatively; consider starting nebulizer and/or steroid therapy if appropriate (e.g., severe disease).
Pursue maneuvers intra-operatively to optimize gas exchange.
Consider regional anesthesia for pain control. Post-operative epidural analgesia may benefit patients with COPD not only because it could provide adequate pain control post-operatively, but also because it can reduce the systemic narcotic requirement and the related complications.
Use inhalation agents during general anesthesia for bronchodilation. However, inhalation agents which may provoke bronchospasm (e.g., desflurane) should be avoided. If the patient has pulmonary hypertension, nitrous oxide should not be used because it can exacerbate pulmonary hypertension.
During maintenance, keep the patient well anesthetized to avoid bronchospasm. Adjust the I:E ratio to allow for adequate expiratory time to minimize auto-PEEP, and use PEEP to reduce atelectasis and shunting. However, be cautious not to rupture an emphysematous bleb.
Post-operatively maintain oxygenation through adequate pulmonary toilet, incentive spirometry, nebulizer and steroid therapy if necessary.

ii. Reactive airway disease (Asthma):

i) Pre-operative evaluation: Assess severity of disease including frequency of exacerbations, triggers (cold weather, environment, medications, and upper respiratory infections), routine and rescue medications, recent oral or IV steroid therapy, emergency room visits, hospitalizations, ICU admissions and intubations.

ii) Peri-operative risk reduction strategies: Continue control medications peri-operatively, and consider a course of nebulizer and/or steroid therapy if the patient appears to have moderate to severe disease. Peri-operative systemic corticosteroids are recommended for persistent symptoms if the peak flow rate and FEV1 are less than 80% predicted or previous best. As with COPD, post-operative epidural analgesia is recommended for patients with severe asthma. The management of general anesthesia should be similar to that of COPD. Avoid relaxants that release histamine. Intubation should be conducted when the patient is deeply anesthetized to reduce intubation induced broncospasm.

c. Renal system:

i. Pre-operative evaluation

Men with urinary retention should have an evaluation of renal function.

i) Urinalysis should be performed to rule out a urinary tract infection. If infection is suspected, a urine specimen should be sent for culture and sensitivity. If an infeciton is present, appropriate antimicrobial therapy must be instituted prior to surgery to prevent urinary sepsis.

ii) Plasma creatinine and urea concentrations provide good information about general renal function. If serum creatinine is elevated due to obstruction, surgery should be delayed until this parameter stabilizes after removal of the obstruction.

iii) Serum electrolyte concentrations and arterial blood gas may reveal a metabolic acidosis or electrolyte imbalance.

ii. Perioperative risk reduction strategies

i) Avoid factors that can compromise renal function.

Nephrotoxic drugs (e.g., aminoglycosides, nonsteroid anti-inflammatory agents).
Hypotension. Excision of large prostatic masses may result in major hemorrhage. Estimated blood loss is dependent on surgeon’s experience and is commonly <500 ml. However, massive bleeding does happen in case of inadequate hemostasis. Therefore, large bore intravenous access is desirable and invasive monitoring should be considered if indicated.
Dehydration. Maintain intra-operative fluid balance to prevent fluid overload while ensuring renal perfusion is not compromised. Due to the pre-operative bowel preparation, the patient is often dehydrated.
Sepsis. Infection should be treated promptly.

ii) Select appropriate anesthetic drugs. The termination of action of most anesthetic drugs is due to redistribution and metabolism. Biotransformation of these drugs usually results in pharmacologically inactive forms of the parent compound which are water soluble and excreted through kidney. Some non-depolarizing muscle relaxants (except atracurium and cisatracurium) are largely eliminated by the kidneys, and dose reduction is required in patients with impaired renal function. Succinylcholine (suxamethonium) administration does cause a rise in serum potassium, which should be avoided in patients who have hyperkalemia.

d. Gastrointestinal system:

Pre-operative evaluation: Assess the likelihood of perioperative aspiration. Be sure to ask if the patient has followed appropriate fasting guidelines and/or symptoms of gastroesophageal reflux disease.
Peri-operative risk reduction strategies for pulmonary aspiration: If full stomach, the surgery should be cancelled since radical prostatectomy is rarely an emergency. If gastroesophageal reflux disease exists, consider placing an awake orogastric tube to decrease gastric fluid volume, as well as utilizing promotility agents, H2-blockers, and antacid medications, prior to performing general anesthesia or neuraxial blocks.

e. Neurologic system:

i. Acute issues: Transient ischemic attack and stroke are unstable medical issues that need to be resolved prior to surgery.

Pre-operative evaluation: A detailed history should be taken and a thorough neuro-exam should be performed (e.g., loss of consciusness, history of cerebrovascular disease, neurological deficits). If necessary, further work-up (e.g., CT, MR, carotid Doppler, neurology consult) should take place prior to surgery.

ii. Chronic disease: A history of carotid or cerebral artery disease may necessitate higher blood pressures in order to maintain adequate cerebral perfusion. Arterial line may be needed. Regional anesthesia is not contraindicated. However, one should consider epidural analgesia induced with gradual bolusing to avoid abrupt sympatholysis and allow time for treatment of hypotension. Consider phenylephrine infusion for prevention of significant hypotension.

f. Endocrine:

Diabetes mellitus is a common co-existing disease in patients undergoing prostatectomy, and an appropriate plan should be made for the management of such patients in the peri-operative period.

i. Pre-operative evaluation should focus on assessing organ damage and blood sugar control. The glycosolated hemoglobin level is not influenced by fasting and, if available, can identify those with poor gluocse control. The American Diabetes Association recommends a target glycosolated hemoglobin level of less than 7%.

ii. Peri-operative risk reduction strategies:

i) If the patient is insulin dependent, glucose level should be determined every 2 hours intra-operatively.

ii) Avoid hypoglycemia and marked hyperglycemia. The American College of Endocrinologists recommends a target fasting glucose level of less than 110 mg/dL in noncritically-ill hospitalized patients. However, data regarding the influence of intensive insulin therapy on outcome after major surgery is relatively scarce. Some studies revealed that tight glucose control may increase the risk of hypoglycemia and lead to a higher morbidity and mortaltily rate in ICU patients. It is currently suggested that peri-operative target glucose levels fall within the range of 140 to 180 mg/dL.

4. What are the patient's medications and how should they be managed in the perioperative period?

Anesthesiologist should obtain a drug history from the patient, including vitamins, herbs and supplements before surgery. They should have knowledge of these medications regarding the classification, indication, and common side effects. The general rule accepted during perioperative management is not altering preoperative drug therapy with exception of following: (1) anticoagulants and fibrinolytic drugs (e.g., clopidogrel [Plavix]) if surgical hemostasis is needed, (2) dosage adjustments for insulin and corticosteroids, (3) nicotinic acid, (4) drugs for erectile dysfunction (i.e., sildenafil [Viagra], vardenafil [Levitra], tadalafil [Cialis], or similar drugs).

Suggestions on commonly used medications:

Antihypertensive medications—Continue on the day of the operation.

Diuretics—Continue on the day of the operation.

Cardiac medications (e.g., digoxin)—Continue on the day of the procedure.

Antidepressant, antianxiety, and psychiatric medications—Continue on the day of the operation.

Thyroid medications—Continue on the day of the operation.

Birth control pills—Continue on the day of the operation.

Eye drops—Continue on the day of the operation.

Heartburn or reflux medications (e.g., Prilosec, Zantac)—Continue on the day of the operation.

Narcotic pain medications—Continue on the day of the operation.

Antiseizure medications—Continue on the day of the operation.

COX-2 inhibitors—Continue on the day of the operation unless the surgeon specifies (usually regarding concerns about bone healing).

NSAIDs—Usually discontinue on the day of the operation.

Vitamins, iron, Premarin—Discontinue on the day of the operation.

Topical medications (e.g., creams and ointments)—Discontinue on the day of the operation.

Oral hypoglycemic drugs—Discontinue on the day of the operation.

Insulin—For all patients, discontinue all regular or combination (70/30 preparations) insulin on the day of the operation or procedure. Type 2 diabetics should discontinue all types of insulin. Type 1 diabetics should take a small amount (usually one-third) of their usual am long-acting insulin (e.g., Lente or NPH) and should not take any short-acting insulin, such as regular insulin, on the day of the procedure. Patients with an insulin pump should continue their basal rate only.

Viagra or similar drugs—Discontinue 36 hours before surgery only when they are not being used for pulmonary hypertension.

Herbals and nonvitamin supplements—Discontinue 7 days before surgery.

MAOIs (monoamine oxidase inhibitors)—Continue with caution of utilizing vasopressors. Consider using phenylephrine in case of hypotension and avoid ephedrine and other indirect-acting agents in patients on MAOIs.

a. Are there medications commonly seen in patients undergoing this procedure and for which should there be greater concern?

Patients undergoing prostatectomy have a higher age-related incidence of cardiovascular diseases, pulmonary diseases, hypertension and diabetes. Careful attention needs to be paid to medications taken for these co-existing diseases.

b. What should be recommended with regard to continuation of medications taken chronically?

Cardiac:

i). Beta blockers— Patients already on beta blockers should continue perioperatively with a goal heart rate of less than 70 beats per minute, which may cause hypotension from reduced contractility and reduction in heart rate. Initiating beta blockers in intermediate and high risk cardiac patients may reduce adverse cardiac events perioperatively. However, studies have not elucidated the ideal length of therapy, which beta blocker is more effective, or how long a patient should continue therapy postoperatively. Additionally, initiating beta blockers perioperatively may be associated with an increased risk of stroke (thought to be due to hypotension) and death.

ii). Statins— Patients on statins should continue perioperatively. Discontinuation is associated with an increased risk of adverse cardiac events and mortality. Starting statins in high risk cardiac patients may reduce adverse cardiac events. However, studies are still evaluating the optimal length of therapy, dosing, titration parameters, and duration of postoperative therapy.

iii). Aspirin—Aspirin should be re-started as soon as possible postoperatively. If aspirin is indicated for a coronary stent, increased vigilance for acute myocardial ischemia and infarction is warranted. Discussion with the surgeon about continuing aspirin through surgery may be necessary to weighing risk of bleeding with risk of peri-operative mycardial infarction.

iv). Clopidogrel— Patients may be on platelet glycoprotein IIB/IIIA receptor inhibitors for coronary stents. If so, identification of drug-eluting versus bare metal stent, as well as the implant date, is needed. Discussion with the surgeon and cardiologist may be necessary to optimize management and balance risk of thrombosis/restenosis against increased risk of bleeding. It is also important to know when to restart antiplatelet aggregation agents. Taking antiplatelet aggregation drugs is a contraindication for neuraxial blocks.

Pulmonary: Continue respiratory medications (inhaled beta agonists, leukotriene inhibitors, inhaled steroid, and oral therapy) perioperatively. The patient may need additional therapy (e.g. inhaled beta agonist as a nebulizer, steroid course) with moderate or severe COPD or asthma.

Renal: Usually continue all the medications on the day of surgery, unless the patient is on specific drugs for renal failure (e.g., phosphate binders).

Neurologic: Patients may be on antiplatelet therapy for cerebrovascular disease. Discussion with primary/surgical team should take place to assess risk of thrombosis/restenosis versus increased risk of bleeding. Antiepileptic and anti-Parkinson medications should be continued perioperatively.

Anticoagulants: Many patients take warfarin for chronic atrial fibrillation and/or peripheral vascular diseases. Discontinuation of warfarin is often necessary. When warfarin is discontinued, anesthesia care providers need to discuss with surgical team and ensure: 1) INR is monitored; 2) whether temporary heparin infusion is needed; 3) when warfarin will be restarted. If INR is greater than 1.5, epidural catheter placement is not advised.

Psychiatric: Continue anti-depressant and anti-anxiety medications perioperatively. However, lithium is usually discontinued 2-3 days prior to the surgery.

5. How To modify care for patients with known allergies?

Any known or potential trigger agents should be identified and avoided.

a. Latex allergy- If the patient has a sensitivity to latex (eg. rash from gloves, underwear, etc.) versus anaphylactic reaction, prepare the operating room with latex-free products.

A list of drugs containing latex bottle tops should be available in every pharmacy. These drugs should have their tops pried open using a bottle opener. All personnel should use non latex gloves, tourniquets, catheters, and all anesthesia equipment must be latex free. All drugs needed for the treatment of an anaphylactic reaction should be readily available before the start of the case. No special pretreatment is required if the above steps are followed.

b. Does the patient have any antibiotic allergies- – Common antibiotic allergies and alternative antibiotics]

If there is ß-lactam allergy, consider Vancomycin or Clindamycin.

c. Does the patient have a history of allergy to anesthesia?

i. Malignant hyperthermia:

i). Documented- avoid all trigger agents such as succinylcholine and inhalational agents:

a). Proposed general anesthetic plan: Prepare the anesthetic machine to ensure there is no trace anesthetic gases. Change the soda lime canister and circuitry and remove all vaporizers for added safety.

b). Insure MH cart available: Check that a sufficient amount of dantrolene is available.

ii). Family history or risk factors for MH: If a close relative had a positive contracture test, then it is not unreasonable to treat the patient as a MH susceptible patient. The fact that the patient may have had previous uneventful anesthetics cannot guarantee that MH is ruled out completely.

ii. Local anesthetics/muscle relaxants: Avoid any known agent to which the patient is allergic.

6. What laboratory tests should be obtained and has everything been reviewed?

Common laboratory normal values will be same for all procedures, with a difference by age and gender

Hemoglobin levels: Patients are frequently dehydrated and thus hemoglobin must be evaluated in light of their volume status (hypovolemic, euvolemic, or hypervolemic).
Platelet count: Because epidural analgesia may be needed, a platelet count should be known prior to epidural catheter placement. Platelet count less than 100,000 is often considered to be a cut off for epidural catheter placement.
Coagulation panel: If INR is greater than 1.5, epidural catheter placement is not advised.
Electrolytes: Any possible electrolytic imbalance and acid-base disorder should be identified before surgery.
BUN/Creatinine Ratio: A ratio greater than 20:1 often suggests hypovolemia.
Imaging: Stress tests and pelvic imaging, etc. CT scan is often available. Reviewing the imaging strengthens the understanding of anatomical abnormality and size of the prostate. Such information is quite useful in planning intra-operative monitoring, intravenous access and potential massive transfusion.
Blood band sample: A valid blood bank sample with type and screen should be obtained pre-operatively from each patient undergoing radical prostatectomy.

7. Intraoperative Management: What are the options for anesthetic management and how to determine the best technique?

The procedure is usually performed under general anesthesia. It can also be done with regional anesthesia (spinal, epidural, combined spinal-epidural) with sedation for open radical prostatectomy. Choice of proper anesthetic technique depends on the surgical approach, patients’ medical condition, and patients’ preference. It should be determined on a case-by-case basis.

a. General anesthesia:

i. Benefits

i) Providing adeuate sedation, analgesia, amnesia and muscle relaxation.

ii) Secured airway, ensuring positive pressure ventilation, reduction of intra-op aspiration and maintenance of PEEP which is necessary for laparoscopic or robotic prostatectomy.

iii) Better management of combative or delirious patients.

iv) Tolerance of positioning which is particularly important for laparoscopic or robotic prostatectomy which requires steep Trendelenburg position.

ii. Drawbacks

i) Inability to communicate with the patient;

ii) Frequent post-operative nausea and vomiting as side effects of general anesthesia.

iii) Swings in hemodynamics, which may increase post opertive cognitive disorder (POCD) in the elderly.

iv) Positive-pressure ventilation used during general anesthesia can reduce cardiac output and may cause pulmonary complications.

v. Prolonged wake-up phase from anesthesia itself – sometimes resulting in a long hang-over effect.

vi. Possibly increased venous bleeding.

iii. Other issues: Need to plan post-operative analgesia especially in open prostatectomy.

iv. Airway concerns: Pay attention to emergency airway plans, particularly for patients with a history of previous difficult intubation and/or mask ventilation and for patients whose airway assessment is not vavorable for intubation.

b. Neuraxial Anesthesia: Can be performed with sedation for an open radical prostatectomy. It is not frequently used in the United States. However, it is often used in other countries for open prostatectomy. With an increasing concern for POCD, particularly for patients with Alzheimer disease, the number of patients requesting regional anesthesia for open prostatectomy appears to be increasing.

i. Benefits

i) Patients with pulmonary disease may benefit from maintenance of spontaneous breathing.

ii) Provides excellent pain control which may preclude the need for intravenous narcotics and minimize their side effects.

iii) Potentially reduces intra-operative blood loss and shortens the time of return of bowel function.

iv) May reduce incidence and severity of POCD in the elderly.

v) Potentially reduces the incidence of postopertive myocardial infarction, hypoxia, deep venous thrombosis and pulmonary embolism.

ii. Drawbacks

i) Contraindicated in patients taking clopidogrel, warfarin, or in patients with coagulopathy. Detailed information is available in American Society of Regional Anesthesia guidelines.

ii) Patient or family refusal may preclude the catheter placement.

iii) Sympatholysis with spinal anesthesia may not be tolerated (e.g. in coronary artery disease, aortic stenosis, cerebrovascular disease)

iv) As it does not necessarily preclude the need for invasive monitoring such as arterial line and CVP, these now need to be placed in an awake/sedated patient.

v) Sedation is often needed and sometimes the patient may loss the consciousness.

vi) It is not suitable for laparoscopic and robotic prostatectomy.

iii. Other issues: Need to plan postoperative anticoagulation therapy with the surgical team. Patients may be started on low molecular weight heparin. However, removal of the catheter needs to be timed appropriately. If low molecular weight heparin is used BID 0.5 mg/kg, insertion or removal of the catheter needs to be delayed until 12 hours after the last dose, and the next dose should be held until two hours after the catheter is removed.

c. Local anesthetic infiltration at incision site

May be considered as a choice of post-operative analgesia in patients who have potential difficulty in post-operative pain management but not suited for epidural analgesia. Bupivacaine (0.5%, 20-30 ml) is usually injected at the incision sites either for open or laparoscopic procedure.

i. Benefits:

i) Can be performed in patients using anti-platelet therapy, with spinal anatomy disease or other contraindications to neuraxial block.

ii) No need to hold anticoagulants.

ii. Drawbacks:

i) Can result in patchy block.

ii) The quality of post-operation pain control may be less satisfactory compared with epidural analgesia.

8. What is the author's preferred method of anesthesia technique and why?

Our preferred choice of open surgery for radical prostatectomy is general anesthesia. Some literature demonstrates that epidural anesthesia combined with general anesthesia decreases intra-operative blood loss and shortens the time to return of bowel function during radical prostatectomy compared with general anesthesia alone. However, epidural anesthesia does not shorten the length of hospital stay. Additionally, because the incision of radical prostatectomy is below umbilicus, post-operative pain control is often not a major issue without epidural analgesia. Therefore, general anesthesia alone is often the choice for radical prostatectomy of patients without cardio-pulmonary co-morbidities.

For robotic or laparoscopic radical prostatectomy, general anesthesia with endotracheal tube is the choice in light of the requirement of steep head down position, and epidural analgesia is not indicated due to limited post-operative pain.

We often start a remifentanyl infusion at approximately 30-45min prior to extubation in order to wean off propofol or wash out inhalation agents. Remifentanyl used in this manner not only significantly reduces the emergence time but also minimizes the likelihood of coughing and bucking during extubation. This technique is very useful if sedation monitoring (e.g., Bispectral Index) is taken to prevent intra-operative awareness.

What prophylactic antibiotics should be administered?

The standard protocol of antibiotic prophylaxis in radical prostatectomy remains to be established.

In our institution the surgeons usually request one dose of a first- or second-generation cephalosporin before making the incision. If there has been a long-term indwelling catheter or preoperative infection, appropriate perioperative antibiotics, such as a cephalosporin and an aminoglycoside or a fluoroquinolone, are indicated.
What do I need to know about the surgical technique to optimize my anesthetic care?

Open Radical prostatectomy

The incision is often small and surgeon will request adequate muscle relaxation. Anesthesia providers should provide muscle relaxation without an overdosing of the relaxation agent. In this regard, continuous monitoring of neuro-muscular blockade should be applied and maintenance of one twitch is desirable.

To reduce intra-operative blood loss and create a better view of the surgical area, patients are often placed in a head down position with extension at the hips. When a head down position is applied, the anesthesia provider must be aware of the potential for air embolism, as the steep head down position can create negative pressure in the venous sinus at the surgical site, and air can be entrained. There are patients who may not tolerate the flexion due to spinal abnormalities and/or back pain. Therefore, testing the tolerance of positioning should be performed prior to induction of anesthesia. Placing pillows under the knees is suggested to minimize complications of the extreme extension position.

In order to reduce the intra-operative bleeding, and to separate prostate from the cavernosal nerve that are necessary for maintaining penile erection function, the surgeon usually injects Tumescent solutions directly into the prostate prior to opening the capsule. One of the commonly used solutions contains lactated Ringer’s 1000 ml, 25 ml of lidocaine (0.5%), 2.5ml of sodium bicarbonate (3.4%), and 1 mg of epinephrine. Generally, 20 to 30 ml of Tumescent solution will be administered into the prostate, which contains 20 to 30 micrograms of epinephrine. Systemic absorption of epinephrine may occur and cause hypertension and tachycardia due to rich blood flow of the prostate. Therefore, when Tumescent solution is injected, the surgeon should notify the anesthesia provider who should be vigilant about monitoring for changes in vital signs, particularly in patients with coronary artery disease.

Diagnostic dyes (1 ml of Methylene blue1% or 5 ml of Indigo carmine 0.8%) may be used during the procedure to demonstrate the integrity of the reconstructed urinary tract. Methylene blue may lead to hypotension. It may also cause transient erroneous decreases in pulse oximetry readings (SaO2) to as low as 65%, lasting 10 to 70 seconds. Indigo carmine, an alpha-agonist, may cause a transient erroneous desaturation last for a few seconds and a transient hypertension. The transient hypertension is often self limiting and does not require treatment.

Laparoscopic or robotic radical prostatectomy

Patients are usually placed in a steep head down position up to 45 degrees (Trendelenburg position) to keep the internal organs away from the surgical site and create adequate space for both laparoscopic and robotic radical prostatectomies. CO2 is insufflated into the surgical field at a intra-abdominal pressure of up to 15 mmHg, which may cause a two to threefold increase in cardiac filling pressure, up to 50 percent decrease in respiratory compliance, and a worsened V:Q mismatch especially in conjunction with steep Trendelenburg position. Moreover, steep Trendelenburg position and CO2 insufflation may compromise the perfusion of internal organs and the lower extremities. It may also increase hydrostatic pressure in the upper body, which could lead to facial, neck, periorbital and possibly brain edema.

In addition, significant hypercarbia may occur when extraperitoneal approach is used. It may result in acidosis, tachycardia, arrhythmias and other deleterious hemodynamic and CNS effects. Hypercarbia could be particularly difficult to manage in the patient with respiratory insufficiency.

Hypotension is often seen at the end of the procedure when the patient is leveled and insufflation of CO2 is discontinued, probably due to redistribution of blood flow to the underperfused areas during steep head-down position. It should be treated accordingly.
What can I do intraoperatively to assist the surgeon and optimize patient care?

Positioning is critical in order to prevent the patient from sliding down during laparoscopic or robotic prostatectomy. Well positioned padding at both shoulders is commonly performed in conjunction with cross-over taping at the chest. It is also helpful to secure both legs when lithotomy position is performed. Testing positioning and external support should be done at the target Trendelenburg tilt prior to draping. After draping, continuous attention is required to ensure that the patient is correctly positioned. There should be no added pressure on vulnerable areas, particularly the elbows, axilla, back, and shoulders. Padding should not impair carotid blood flow on either side.

The position of the tracheal tube should be checked regularly. Endotracheal tube migration may occur with physical movement of the diaphragm and mediastinum by the pneumoperitoneum and steep head down position.

Fluid replacement to compensate for fluid deficits due to bowel preparation and fasting should take place early during surgery, particularly in elderly patients, while being careful not to cause volume overload. However, adequate rehydration may not be easy to determine during prostatectomy as urine output cannot be measured once the bladder is open. Three to four litters of crystoid fluid is often given intra-operatively in patients with no major cardiopulmonary or renal disease if estimated blood loss is less than 300 ml. For laparoscopic surgery, surgeons may desire less fluid as high urine output can obscure view of the surgical field. Patients with end stage renal disease may benefit from central venous pressure monitoring to guide fluid administration

Blood loss during radical prostatectomy is between 100 ml to 500 ml. This rarely meets the threshold to transfuse. However, due to the rich blood supply of the prostate, major bleeding may occur. Therefore, it is prudent to have two to three units of blood available if the surgeons anticipate more than average bleeding.
What are the most common intraoperative complications and how can they be avoided/treated?

Hemorrhage– Due to the small surgical field, the surgeon may have difficulty controlling bleeding and a significant amount of blood loss can occur in short time period. One approach possibly effective for reducing blood loss is placing the patient into head down position to reduce the venous pressure at the surgical site, as the venous blood loss is proportional to the transmural pressure and head down positioning can effectively reduce the transmural pressure.

Cardiac complications– For those patients with cardiopulmonary co-morbidities, myocardial oxygen supply/demand ratio should be optimized perioperatively. The need for invasive monitoring should be assessed. Postoperatively, shivering should be avoided as it may increase oxygen consumption. Postoperative pain should be controlled since it may trigger a stress response leading to tachycardia, hypertension, increased oxygen demand, and myocardial ischemia. Beta-blockers and statins should be continued if previously used. Anticoagulants and/or anti-platelet aggregation agents for cardiac stents should be resumed when appropriate. Telemetry or intensive care should be considered.

Hypoxemia– For the mini-invasive prostatectomy, the application of PEEP and increasing peak inspiratory pressure could be used to treat hypoxemia caused by CO2 insufflation of the peritoneum and the steep head down position after exclusion of other etiologies such as endotracheal tube migration. However, both maneuvers lead to an increase in airway pressure which in turn causes circulatory compromise. If the patient experiences persistent hemodynamic instability or hypoxemia is resistant to the application of PEEP, the operation may be converted to an open procedure.

Hypercarbia– Mini-invasive prostatectomy often leads to substantial CO2 absorption. Increase in minute alveolar ventilation is necessary to maintaining isocarbia. Sometimes, maintaining hypocarbia in patients with obstructive lung diseases or asthma and intermittent discontinuation of CO2 insufflation is required.

Gas embolism– High incidence of subclinical gas embolism has been reported both in open radical prostatectomy and laparoscopic or robotic procedures. Although most of these subclinical gas embolisms do not cause any cardio-respiratory disabilities, close monitoring of possibly fatal gas embolism should be considered especially during transection of deep dorsal venous complex.

Regurgitation– An oral gastric tube is indicated in laparoscopic and robotic prostatectomy. Because a steep head-down position often leads to gastric fluid regurgitation, suction through the oral gastric tube to reduce the gastric fluid and air volume should be done prior to placing the patient in steep head-down position.

Subcutaneous emphysema is frequently encountered due to CO2 insufflation of peritoneum. Other rare complications can also occur including capnothorax, pneumothorax, pneumomediastinum, pneumopericardium, increased intracranial pressure, increased intraocular pressure, brachial plexopathy, and arthralgias.

9. If the patient is intubated, are there any special criteria for extubation?

Prior to extubation, the patient should be awake, alert, and able to respond to command and generate adequate tidal volume. The majority of patients are extubated at the completion of surgery, and post-operative mechanical ventilation is not indicated. Occasionally, patients with severe respiratory insufficiency may need a short-term course of ventilatory support post-operatively.

For those who receive laparoscopic or robotic radical prostatectomy, there is a risk that subcutaneous emphysema may extend along the tissue planes around the neck. Prolonged steep head-down position and/or major fluid administration may also create severe pharyngeal edema, which may cause airway obstruction after extubation. Therefore, careful assessment of airway edema prior to extubation is necessary. Sometimes, the patient may be kept intubated and placed in a sitting position to allow resolution of edema, after then they can be extubated either in ICU or post anesthesia care unit.

10. Postoperative management

What analgesic modalities can I implement?

Because the incision is below the umbilicus for open prostatectomy or very small for laparoscopic approach, post-operative pain control is often not a major issue without epidural analgesia. Commonly, intra-operative administration of hydromorphone (2mg, intravenously) is adequate and does not require additional narcotic immediately post-operatively. For patients with advanced age, obstructive sleep apnea and/or severe pulmonary diseases, the hydromorphone dose should be reduced accordingly. Local anesthetic at the incision site is beneficial to manage post operative pain. Patient-controlled intravenous analgesia is not often needed. However, for patients with cardiopulmonary co-morbidities, epidural analgesia for post-operative pain management seems advantageous. This is because systemic narcotics may cause undesirable side effects including respiratory drive suppression, limited coughing ability, and smaller tidal volumes. It may also be associated with a high incidence of post-operative pneumonia.
What level bed acuity is appropriate?

The choice of floor, telemetry, and step down or ICU admission depends on the patient’s pre-operative co-morbidities, intra-operative course, and hospital resources.
What are common postoperative complications, and ways to prevent and treat them?

Surgical mortality for open prostatectomy should be less than 1%. Myocardial infarction, pneumonia, and pulmonary embolus are the most common complications after prostatectomy. Early ambulation, leg movement in bed, and breathing exercises could decrease mortality.

What's the Evidence?

Klein, Eric A, Platz, Elizabeth A, Thompson, Ian M. “Chapter 90 – Epidemiology, Etiology, and Prevention of Prostate Cancer”. Wein: Campbell-Walsh Urology. 2007. (This chapter gives us an overview of radical prostatectomy.)

Dahl, Douglas M, Barry, Michael J, McGovern, Francis J, Chang, Yuchaio, Walker-Corkery, Elizabeth, McDougal, W. Scott. “A prospective study of symptom distress and return to baseline function after open versus laparoscopic radical prostatectomy”. J Urology. vol. 182. 2009. pp. 956-66. (This prospective study demonstrated comparable outcomes in open and laparoscopic radical prostatectomy.)

Malhotra, Vinod, Sudheendra, Vijayendra, O’Hara, Jerome, Diwan, Sudhir, Miller, RD. “Chapter 65: Anesthesia for the Renal and Genitourinary Systems”. Anesthesia. 2009. pp. 1934-1959. (Preparation of the patient for sugery, complications during surgery, and management of the post surgical period.)

Lestar, M, Gunnarsson, L, Lagerstrand, L, Wiklund, P, Odeberg-Wernerman, S. “Hemodynamic Perturbations During Robot-Assisted Laparoscopic Radical Prostatectomy in 45{degrees} Trendelenburg Position”. Anesth Analg. 2011. (This prospective study of 16 patients undergoing robotic assisted radical prostatectomy reported that pneumoperitoneum and 45° Trendelenburg position caused 2- to 3-fold increases in filling pressures and halved lung compliance.)

Stevens, RA, Mikat-Stevens, M, Flanigan, R, Waters, WB, Furry, P, Sheikh, T, Frey, K, Olson, M, Kleinman, B. “Does the choice of anesthetic technique affect the recovery of bowel function after radical prostatectomy?”. Urology.. vol. 52. 1998. pp. 213-8. (This prospective randomized clinical trial enrolled 40 patients, and demonstrated epidural anesthesia combined with light general anesthesia decreased intraoperative blood loss and shortened the time to return of bowel function.)

Dunet, F, Pfister, Ch, Deghmani, M, Meunier, Y, Demeilliers-Pfister, G, Grise, P. “Clinical results of combined epidural and general anesthesia procedure in radical prostatectomy management”. Can J Urol.. vol. 11. 2004. pp. 2200-4. (This retrospective study demonstrated combined epidural and general anesthesia has a potentiality to decrease blood loss.)

Hong, JY, Kim, JY, Choi, YD, Rha, KH, Yoon, SJ, Kil, HK. “Incidence of venous gas embolism during robotic-assisted laparoscopic radical prostatectomy is lower than that during radical retropubic prostatectomy”. Br J Anaesth.. vol. 105. 2010. pp. 777-81. (This prospective study of 52 patients undergoing radical prostatectomy reported a high incidence of venous gas embolism both in open radical prostatectomy and robotic-assisted laparoscopic radical prostatectomy.)

Hong, JY, Kim, WO, Kil, HK. “Detection of subclinical CO2 embolism by transesophageal echocardiography during laparoscopic radical prostatectomy”. Urology.. vol. 75. 2010. pp. 581-4. (This study reported subclinical gas embolism occurred in about 17% of the patients receiving laparoscopic radical prostatectomy.)

No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC. The Licensed Content is the property of and copyrighted by DSM.

Jump to Section

Anesthesiology

Radical prostatectomy – Procedures