What the Anesthesiologist Should Know before the Operative Procedure
While urinary incontinence is prevalent in a large number of women (roughly half of all women aged 20 to 80 by survey studies), fewer than half will seek consultation and treatment for this condition. Many older women may have comorbidities (such as cardiovascular disease, diabetes mellitus, smoking history, obesity, among others), which should be the focus of the anesthesiologist. In addition, causes of urinary incontinence such as central nervous system dysfunction (see below; e.g., tumors, injury or infarction, diabetes insipidus, infectious causes), endocrine disorders (diabetes mellitus, hypercalcemia treatment), or volume overload (venous insufficiency or congestive heart failure) should be addressed.
For more information, please see this review on female urinary incontinence: Castro RA, Arruda RM, Bortolini MA. Female urinary incontinence: effective treatment strategies. Climacteric 2015 Apr; 18(2): 135-41. DOI: 10.3109/13697137.2014.947257.
Surgical procedures to address female urinary incontinence generally fall into one of seven categories:
Open abdominal retropubic colposuspension
Laparoscopic retropubic colposuspension
Anterior vaginal repair/colporrhapy
Suburethral slings (midurethral and retropubic, both via open and minimally invasive routes)
Periurethral or transurethral injections
1. What is the urgency of the surgery?
What is the risk of delay in order to obtain additional preoperative information?
Rarely is female urinary incontinence surgery itself emergent or urgent in nature; the overwhelming majority of procedures are done on an elective basis. However, there are conditions leading to some forms of urinary incontinence that may lead to extreme morbidity or even mortality if unrecognized or untreated (see below); these cases should be evaluated and the underlying causes addressed in a timely fashion prior to performing urinary incontinence procedures.
Emergent: Causes of urinary incontinence that may be related to conditions with morbidity or mortality, if unrecognized or untreated, may be as follows: conditions related to central nervous system dysfunction (tumors; ischemia; infarction; traumatic injury; hemorrhage; degeneration such as Parkinson’s disease or dementia; multiple sclerosis; infectious causes such as AIDS or neurosyphilis), endocrine dysfunction (uncontrolled diabetes mellitus with hyperglycemia, hypercalcemia), or a relatively hypervolemic state (venous insufficiency, congestive heart failure).
Urgent: Obstructive sleep apnea with nocturnal disturbance may be a cause of reversible urinary incontinence, and should be ruled out.
Elective: The majority of cases of female urinary incontinence surgery are elective, and thus patients should be fully evaluated and counselled for risks related to either surgery or anesthesia. Female urinary incontinence surgery is generally thought to be a low-risk surgery; however, patient comorbidities may be frequently encountered and appropriate preparations made.
2. Preoperative evaluation
Multiple significant comorbidities may be present in this patient population, and should be evaluated carefully for anesthetic implications.
Medically unstable conditions warranting further evaluation include: any life-threatening systemic diseases or aberrant vital signs should necessitate immediate workup and treatment, ideally through an emergency department or appropriate consultation (e.g., cardiologist involvement with a patient displaying signs and symptoms of unstable angina or myocardial ischemia).
Delaying surgery may be indicated if: unstable or inadequately evaluated conditions warrant collecting additional information prior to proceeding with female urinary incontinence surgery on an elective basis.
3. What are the implications of co-existing disease on perioperative care?
b. Cardiovascular system
Any life-threatening cardiac conditions should immediately take precedence for workup and treatment, and surgery should be delayed or cancelled. Cardiologist involvement should be early, especially in circumstances of decompensated heart failure, unstable angina, recent myocardial infarction, severe valvular disease, and/or significant arrhythmia.
Baseline coronary artery disease or cardiac dysfunction – goals of management
Optimization of myocardial oxygen delivery in the face of myocardial oxygen demands as a generic goal is aligned with goals for female urinary incontinence surgical patients. Initial assessment, including review of history and functional status, review of cardiac testing and procedures, and obtaining recent cardiology input are key. Continuation of statin treatment, beta blockade, aspirin therapy (see Ref), along with other antihypertensives should be considered. Please see the ACC/AHA 2014 Guidelines for perioperative cardiovascular evaluation and management of patients for noncardiac surgery, which offers further recommendations related to risk stratification and need for further workup: http://circ.ahajournals.org/content/130/24/2215.long.
Thorough history, physical exam, assessment of functional status and symptomatology, along with radiologic studies (chest x-ray, chest computed tomography scan) and pulmonary function tests are needed. Exacerbation history, baseline supplemental oxygen utilization, and hospitalizations could be clues to severity of disease and whether the patient is optimized. Perioperative risk reduction strategies include maintaining the patient’s inhaler regiment, avoiding cholinergic agents, and encouraging use of incentive spirometry preoperatively. Lithotomy position is very common for this procedure and may confer risk related to decreased vital capacity.
Reactive airway disease (asthma)
Thorough history, physical exam, assessment of functional status and symptomatology, along with any available pulmonary function tests are needed. History of intubations, hospitalizations for asthma, and need for steroids to control asthma could be clues to severity of disease and whether the patient is optimized. Perioperative continuation of beta-agonists may be helpful, and neuraxial techniques may be preferred in these patients.
Usual concerning renal or gastrointestinal conditions should be assessed during a preoperative anesthetic consultation for female urinary incontinence surgery, as they are for other surgical procedures.
Neurological considerations related to urinary incontinence should be ruled out or addressed, as above (conditions related to central nervous system dysfunction such as tumors, ischemia, infarction, traumatic injury, hemorrhage, degeneration such as Parkinson’s disease or dementia, multiple sclerosis, infectious causes such as AIDS or neurosyphilis). Elective surgery should be postponed or cancelled in light of concerning findings that need further evaluation.
Any endocrine problem should be addressed and a plan formed for control during the perioperative period, specifically focusing on common conditions such as diabetes mellitus, hypothyroidism, and hyperparathyroidism. If concerns arise about changing or unstable conditions, elective surgery should be postponed or cancelled and the patient reevaluated for medical optimization.
g. Additional systems/conditions which may be of concern in a patient undergoing this procedure and are relevant for the anesthetic plan (eg. musculoskeletal in orthopedic procedures, hematologic in a cancer patient)
Musculoskeletal (specifically, osteoarthritis, low back pain, and osteoporosis) may be present and should be attended to with regards to positioning patients in the lithotomy position. Hematologic parameters must always be evaluated when considering a neuraxial technique (please see Horlocker et al. 2010 in Reg Anesth Pain Med for the 3rd edition 2010 American Society of Regional Anesthesia (ASRA) Consensus Statement).
4. What are the patient’s medications and how should they be managed in the perioperative period?
h. Are there medications commonly seen in patients undergoing this procedure and for which should there be greater concern?
No additional medications (outside of those commonly prescribed for comorbidities) are associated with female urinary incontinence and which should be specifically considered.
i. What should be recommended with regard to continuation of medications taken chronically?
(Please refer to Fostnot CD, Fleisher LA, Keogh J. Curr Opin Anaesthesiol 2015; 28(6): 617-22 for an updated profile of current trends and guidelines seen in the ambulatory surgical setting.)
Cardiac (in absence of concerning side effects or adverse effects): Continue all antihypertensives (except for ACE inhibitors or angiotensin-receptor blockers–consider discontinuing these to avoid possibility of treatment-resistant hypotension upon initiation of anesthesia). Continue beta blockade if pt is on beta blockers chronically. Continue statin therapy in patients currently taking a statin. Discuss antiplatelet agents with cardiologist and surgical team (aspirin may be considered appropriate for continuing; other antiplatelet agents may be stopped due to bleeding risks, either surgical or neuraxial in nature).
Pulmonary: Continue inhalant regimen.
Renal: Hold diuretic agents when patient is nothing by mouth (NPO) to avoid volume depletion and potential electrolyte imbalances.
Neurologic: Continue anti-parkinsonian therapies and antiepilepsy medications.
Antiplatelet: See above; have discussion with cardiologist and surgical team as to whether bleeding risk outweighs major adverse cardiac event risk.
Psychiatric: Continue antidepressant medications.
Herbal medications: Hold all herbal medications and over-the-counter medications.
j. How to modify care for patients with known allergies –
Consult pharmacist with questions about structural similarity of classes of medications if a patient exhibits a reaction to a commonly agent (e.g., fentanyl is structurally dissimilar to morphine and many other opioid derivatives, and may be considered in a patient with a true allergy to morphine). In addition, severity of reaction may determine suitability of use of similar medications (e.g., simple drug rash is less severe of an immune reaction than hives/urticaria, which may impact choices of drugs with class cross-reactivity).
For more information on the spectrum of allergic reactions, please refer to this excellent review article of anaphylaxis in the perioperative period: Mali S. Anaphylaxis during the perioperative period. Anesth Essays Res 2012 Jul-Dec; 6(2): 124-33. DOI: 10.4103/0259-1162.108286.
k. 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.
l. Does the patient have any antibiotic allergies- – Common antibiotic allergies and alternative antibiotics]
What prophylactic antibiotics should be administered?
Per the 2016 update for the 2008 guidelines published by the American Urological Association (found at: https://www.auanet.org/education/guidelines/antimicrobial-prophylaxis.cfm), a first- or second-generation cephalosporin (such as cefazolin) is acceptable for prophylaxis. Alternative first-line antibiotic prophylaxis agents include aminoglycosides or aztreonam in combination with metronidazole or clindamycin. If none of these can be given due to allergic history or patient comorbidities, alternatives include ampicillin/sulbactam or fluoroquinolones. Duration of antibiotic therapy is generally continued for the first 24 hours. Please refer to https://www.auanet.org/education/guidelines/antimicrobial-prophylaxis.cfm for further details.
m. Does the patient have a history of allergy to anesthesia?
Documented: avoid all trigger agents such as succinylcholine and inhalational agents:
Proposed general anesthetic plan: For general anesthetics, it is imperative to use a “clean” circuit and machine, or newer modalities such as charcoal circuit filters, along with a nontriggering anesthetic (via a Total Intravenous Anesthesia technique, or TIVA). Nondepolarizing muscle relaxants are safe, as is nitrous oxide. For further details on malignant hyperthermia (MH), please visit www.mhaus.org for the most up-to-date information.
Ensure MH cart available: Dantrolene should be available for treatment of malignant hyperthermia at all anesthetizing locations.
Family history or risk factors for MH: Risk factors for MH should be assessed in every patient undergoing an anesthetic, and should there arise any questionable history, precautions should be taken (as above) to avoid triggering agents. Please visit www.mhaus.org to discuss with an on-call consultant should there be questions concerning a patient’s risk stratification.
Local anesthetics/ muscle relaxants: Should the patient have evidence of an upper motor neuron process contributing to urinary incontinence, care should be taken to avoid succinylcholine which could lead to hyperkalemia due to depolarization of proliferated extrajunctional nicotinic acetylcholine receptors from denervation. In the case of a spinal cord injury, it is important to assess risk of autonomic hyperreflexia and have adequate anesthesia prior to surgical stimulation.
5. What laboratory tests should be obtained and has everything been reviewed?
(Please refer to Hofer J, Chung E, Sweitzer BJ. Preanesthesia evaluation for ambulatory surgery: do we make a difference? Curr Opin Anesthesiol 2013; 26: 669-76, and the ASA’s 2012 Practice Advisory for Preanesthesia Evaluation. Anesthesiology 2012; 116: 522-38.)
In the otherwise healthy patient (ASA 1 or 2), no additional preoperative testing (laboratory, imaging, or studies) is necessary for this low-risk procedure.
Hemoglobin levels: In high-risk patients with comorbidities, hemoglobin levels may be considered. Type and screen is generally not necessary.
Electrolytes (including glucose): May be useful in high-risk patients based on medication use (e.g., diuretic therapy or digoxin) and comorbidities (e.g., renal dysfunction, diabetes mellitus).
Coagulation panel: As patient history or comorbidities warrant. In a patient being considered for neuraxial technique, concerning history for abnormal bleeding episodes (or anticoagulation therapy, e.g., warfarin or heparin) should prompt laboratory assessment of coagulation.
Imaging: Based on patient comorbidities, imaging studies may be helpful to guide perioperative planning.
Other tests: Any concern for uncontrolled systemic disease (e.g., thyroid conditions) should prompt laboratory evaluation of such conditions. Pregnancy testing is not currently routine in many centers given reliable patient history of last menstrual period, sexual practices, and decision-making capabilities.
Intraoperative Management: What are the options for anesthetic management and how to determine the best technique?
Female urinary incontinence procedures are predominantly done under general or neuraxial anesthesia. Patient selection with specific attention to comorbidities or contraindications to neuraxial anesthesia should be the focus of choosing the anesthetic plan. Patients are commonly in the lithotomy position, so this should factor into decision-making as well.
Specifics regarding the appropriateness (for the general option) and the benefits/drawbacks/issues (eg., antiplatelet agents for regional) should be included in each section. In the regional section, include any adjuvants like common sedation or general. A discussion of patient positioning and any special concerns with regard to positioning injury should be included.
Stress urinary incontinence procedures have been performed under neuraxial techniques with success. In addition, neuraxial anesthesia allows for the awake and cooperative patient to cough during surgical repair should the surgeon so desire, thus “testing” the repair for efficacy intraoperatively.
(for more details, please visit the NYSORA website: http://www.nysora.com/regional_anesthesia/neuraxial_techniques/3119-spinal_anesthesia.html)
Benefits: Possible reduction in post-operative nausea and vomiting (PONV) in high-risk patients; may be used without sedation in patients with comorbidities as sole anesthetic technique.
Drawbacks: Relative inflexibility of duration with spinal anesthetic; epidural or combined spinal-epidural techniques theoretically allow for more flexibility of duration but may take longer to place; sacral anesthetic coverage occasionally more challenging to obtain with epidural techniques.
Issues: When placing spinal anesthetic, consider using hyperbaric anesthetic solution (e.g., hyperbaric 0.75% bupivacaine) and having patient sit upright to produce an adequate saddle block for procedure. Isobaric local anesthetic (e.g., bupivacaine 0.5%) may also be used intrathecally with success; common dosing practice is 8-10mg of hyperbaric bupivacaine will allow for 210-240 minutes of perineal surgery. Open procedures may necessitate a higher block (T4) and may require 15-20mg of specifically hyperbaric bupivacaine to achieve the reliable T4 level; regression of T4 level plays a large part in considerations for this technique for open or laparoscopic procedures, since regression of block height leading to inadequate anesthesia (approximately 1.5-2 hours into the procedure) may necessitate conversion to a general anesthetic.
Patients may undergo general anesthesia, which has been used also with success. While “coughing” per se is not usually desirable under general anesthesia, coughing is not always necessary during this procedure, as the surgeon may be able to press briefly on the bladder to “test” the urinary incontinence repair. Valsalva maneuver does not tend to generate high enough pressures to mimic in vivo stress incontinence, and may have cardiovascular and pulmonary consequences if attempted too aggressively or for a prolonged period.
Benefits: Securing of the airway; flexible duration of surgery.
Drawbacks: May increase risk of PONV in certain high-risk patients; some patients may be difficult to assess under general anesthesia for need for pain medication (e.g., pre-existing beta blockade); inability to elicit leakage due to stress incontinence triggers should the surgeon request patient to cough, laugh, etc.
Other issues: Consider need for patient involvement in “testing” the repair (usually dictated by surgeon’s preference).
Airway concerns: Usual considerations should be taken.
Monitored anesthesia care
Many of the less invasive sling procedures were originally described as performed under local anesthesia; however, these are largely being done using general anesthesia due to possibility of groin pain encountered during dissection, among other factors.
6. What is the author’s preferred method of anesthesia technique and why?
General anesthesia via LMA or ETT is a reasonable choice, since it allows for securing of the airway and flexibility with duration of anesthetic should complications arise. With appropriate PONV prophylaxis, it has been utilized successfully by this author for ambulatory surgical incontinence procedures.
What prophylactic antibiotics should be administered?
Per the 2016 update of the 2008 guidelines published by the American Urologic Association (see “What’s the evidence” section), a 1st or 2nd generation cephalosporin (such as cefazolin) is acceptable for prophylaxis. Alternative first-line antibiotic prophylaxis agents include aminoglycosides, aztreonam, metronidazole, or clindamycin. If none of these can be given due to allergic history or patient comorbidities, alternatives include ampicillin/sulbactam or fluoroquinolones.
What do I need to know about the surgical technique to optimize my anesthetic care?
Surgical technique may be open or laparoscopic, and may range from bladder neck suspension surgery (Burch retropubic colposuspension) to pubovaginal sling surgery (utilizing autologous tissues), to a synthetic sling (e.g., tension-free vaginal tape, transobturator tape, or suprapubic-arc sling) which incorporates synthetic material to suspend the urethra. Patients may be discharged to home or admitted following surgery; average length of stay if admitted ranges from 1.1 to 5.8 days, with increasing age positively correlating with increasing length of stay (see Ref).
What can I do intraoperatively to assist the surgeon and optimize patient care?
Discuss whether the surgeon plans to “test” the intraoperative repair, and if so, whether (s)he prefers the patient to cough on command or would prefer to press briefly on the bladder.
What are the most common intraoperative complications and how can they be avoided/treated?
Critical: Vascular injuries to iliac or obturator vessels or hemorrhage from venous plexus injury; bladder injury; bowel injury. More common but less critical: neurologic injury from lithotomy position; back discomfort from being in lithotomy position; possible post-dural puncture headache from neuraxial anesthetics (lithotomy, early ambulation are risk factors). Proper attention to positioning may help avoid neurologic injury (e.g., lower extremity neuropathies, see Ref).
Female urinary incontinence surgery does not incur additional complications unique to the procedure which have not been discussed in other sections (see below for procedure-specific complications). Considerations of the impact of the lithotomy position on the patient’s comorbidities should be fully evaluated.
Unique to procedure: Female incontinence surgical procedures are generally thought to be safe; however, complications may include bladder injury, pelvic hematoma or hemorrhage (from pelvic venous plexus injury or direct vascular injury to iliac or obturator vessels), transient perineal pain or groin pain caused by dissection and/or sling positioning, transient voiding dysfunction (mainly urinary retention), and rarely, bowel injury.
b. If the patient is intubated, are there any special criteria for extubation?
There are no additional special criteria for extubation, other than taking into account comorbidities such as obesity with its associated problems (pulmonary factors such as decreased functional reserve capacity; a tendency toward more difficult mask ventilation and intubation) may be present in this population.
c. Postoperative management
What analgesic modalities can I implement?
Standard intravenous and oral analgesics, in a multimodal fashion, are appropriate. Groin pain from dissection and sling position may be present later in the postoperative follow-up period, and may be treated by the surgeon in the clinic with localized injections of steroid and local anesthetic (see Ref).
What level bed acuity is appropriate?
Depending on type of procedure, patients may either be discharged to home in the ambulatory surgery setting, or may be admitted to the floor. Patient comorbidities should play a factor as well in bed acuity, taking into account frequency of nursing interventions and assessments along with changing patient conditions.
What are common postoperative complications, and ways to prevent and treat them?
Urinary retention may occur and necessitates surgical evaluation with possible indwelling urinary catheter placement. Perineal discomfort may be treated with analgesics until its resolution. Lower extremity neuropathies from lithotomy positioning have been reported as predominantly sensory dysfunction, but motor function should always be assessed prior to discharge from a post-anethesia care unit.
What’s the Evidence?
WHAT THE ANESTHESIOLOGIST SHOULD KNOW BEFORE THE OPERATIVE PROCEDURE
“ACOG Practice Bulletin No. 155: Urinary Incontinence in Women”. . vol. 126. 2015 Nov. pp. e66-81. (General overview of the scope of female urinary incontinence, including evaluation strategies and ACOG recommendations.)
Ford, AA, Rogerson, L, Cody, JD, Ogah, J. “Mid-urethral sling operations for stress urinary incontinence in women”. . 2015 Jul 1. pp. CD006375(Cochrane review [meta-analysis] of mid-urethral sling procedures; provides a brief overview of types of female urinary incontinence procedure types along with an in-depth analysis of procedural outcomes involving mid-urethral sling procedures.)
PERIOPERATIVE RISK REDUCTION STRATEGIES: CARDIOVASCULAR
Kiberd, MB, Hall, RI. “Aspirin in the perioperative period: a review of the recent literature”. . vol. 28. 2015 Jun. pp. 349-55. (A review of recent literature regarding the perioperative administration of aspirin, both for primary and for secondary prevention of thrombotic events.)
WHAT PROPHYLACTIC ANTIBIOTICS SHOULD BE ADMINISTERED?
Wolf, JS, Bennett, CJ, Dmochowski, RR, Hollenbeck, BK, Pearle, MS, Schaeffer, AJ. “Urologic Surgery Antimicrobial Prophylaxis Best Practice Policy Panel. Best practice policy statement on urologic surgery antimicrobial prophylaxis”. J Urol. vol. 179. 2008 Apr. pp. 1379-90. (Discusses appropriate antibiotic prophylaxis for vaginal/urologic procedures, including vaginal sling procedures.)
WHAT DO I NEED TO KNOW ABOUT THE SURGICAL TECHNIQUE TO OPTIMIZE MY ANESTHETIC CARE?
Castro, RA, Arruda, RM, Bortolini, MAT. “Female urinary incontinence: effective treatment strategies”. . vol. 18. 2015. pp. 135-41. (Recent review of all urinary incontinence treatment strategies, including non-pharmacological, pharmacological, and surgical treatment options, as well as common postsurgical complications.)
WHAT ANALGESIC MODALITIES CAN I IMPLEMENT?
Duckett, J, Baranowski, A. “Pain after suburethral sling insertion for urinary stress incontinence”. . vol. 24. 2013 Feb. pp. 195-201. (Literature review regarding current evidence on pain after suburethral sling insertion, which discusses possible long-term treatments of postoperative pain, including local anesthetic/steroid injections, cognitive behavioral therapy, as well as surgical removal of slings or tapes.)
WHAT ARE THE MOST COMMON INTRAOPERATIVE COMPLICATIONS AND HOW CAN THEY BE AVOIDED/TREATED?
Warner, MA, Warner, DO, Harper, CM, Schroeder, DR, Maxson, PM. “Lower extremity neuropathies associated with lithotomy positions”. . vol. 93. 2000 Oct. pp. 938-42. (Overview of common risk factors associated with lower extremity neuropathies from lithotomy position.)
COMPLICATIONS UNIQUE TO PROCEDURE:
Garely, AD, Noor, N. “Diagnosis and surgical treatment of stress urinary incontinence”. . vol. 124. 2014 Nov. pp. 1011-27. (Review of common surgical approaches to female urinary incontinence surgery and their associated complications.)
Kirby, AC, Tan-Kim, J, Nager, CW. “Midurethral slings: which should I choose and what is the evidence for use”. . vol. 27. 2015 Oct. pp. 359-65. (Review of and comparisons between common female urinary incontinence surgical techniques, with attention to emerging minimally invasive procedures, such as single-incision slings.)
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- What the Anesthesiologist Should Know before the Operative Procedure
- 1. What is the urgency of the surgery?
- What is the risk of delay in order to obtain additional preoperative information?
- 2. Preoperative evaluation
- 3. What are the implications of co-existing disease on perioperative care?
- b. Cardiovascular system
- c. Pulmonary
- d. Renal-GI:
- e. Neurologic:
- f. Endocrine:
- g. Additional systems/conditions which may be of concern in a patient undergoing this procedure and are relevant for the anesthetic plan (eg. musculoskeletal in orthopedic procedures, hematologic in a cancer patient)
- 4. What are the patient’s medications and how should they be managed in the perioperative period?
- h. Are there medications commonly seen in patients undergoing this procedure and for which should there be greater concern?
- i. What should be recommended with regard to continuation of medications taken chronically?
- j. How to modify care for patients with known allergies -
- k. 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.
- l. Does the patient have any antibiotic allergies- - Common antibiotic allergies and alternative antibiotics]
- What prophylactic antibiotics should be administered?
- m. Does the patient have a history of allergy to anesthesia?
- 5. What laboratory tests should be obtained and has everything been reviewed?
- Intraoperative Management: What are the options for anesthetic management and how to determine the best technique?
- 6. What is the author’s preferred method of anesthesia technique and why?
- What do I need to know about the surgical technique to optimize my anesthetic care?
- What can I do intraoperatively to assist the surgeon and optimize patient care?
- What are the most common intraoperative complications and how can they be avoided/treated?
- a. Neurologic
- b. If the patient is intubated, are there any special criteria for extubation?
- c. Postoperative management