Perception of pain during uterine aspiration is a complex phenomenon influenced by both physical and psychosocial elements, and as such, can vary considerably between individuals. The table below summarizes the research to date. In the multivariable analyses, no single factor predicts procedure-associated pain (Singh 2008).
FACTORS ASSOCIATED WITH PAIN DURING UTERINE ASPIRATION
|Increased Pain||Decreased Pain||Conflicting Results||Not Strongly Associated|
Expectation of pain
Younger patient age
|Previous vaginal delivery
Older patient age
Shorter operative time
Participation in the
choice of anesthesia
Max cervical dilation
Comfort with decision
|Prior pelvic exam
Prior uterine aspiration
Prior cesarean section
Manual vs. electric
Many patients are anxious about anticipated procedural pain. Supportive verbal communication, including distraction and so-called “vocal local” or “verbicaine”, can play a role in reducing anxiety and pain. Providers can acknowledge the possibility of pain without overly alarming patients. Offering elements of positive suggestion may help to allay concerns. For example:
“Most patients are worried about pain, and are often surprised that the procedure is faster and more tolerable than they expected. Patients have varying amounts of pain, but I will be giving you some numbing medicine and will show you some breathing techniques to help. I will be as gentle as possible.”
Guiding patients to take slow, deep, regular breaths can assist in relaxation, avoid hyperventilation, and also give patients an increased sense of control. Instead of pulling away and tightening, encourage patients to release or push their hips into the table.
Guided imagery can also decrease anxiety and analgesic requirements for surgical patients (Gonzales 2010). Patients may be invited to recall a favorite place, activity, or color, during the procedure. Relaxing images or mobiles above the exam table have also been used to decrease pain and anxiety during gynecologic procedures (Carwile 2014). Playing music in the room may be helpful with anxiety and satisfaction, but does not decrease pain (Wu 2012, Guerrero 2012, Cepeda 2006). A heating pad or hot water bottle may be helpful during the procedure, in recovery or at home.
CHOICE OF PAIN CONTROL METHODS
Relevant information about pain management should be reviewed as part of the informed consent process, including the range of patient experiences, available options for pain control, as well as their risks and benefits. If a patient has a strong preference for an option your facility does not offer, an appropriate referral can be given.
Premedication with NSAIDs has been shown to decrease pain during and after the procedure, and has few contraindications or side effects (Ipas 2016). Some patients choose this less sedating option in order to be more alert, have shorter recovery, or to drive themselves home
Other patients may choose a more sedating option to be more relaxed, to manage higher levels of anxiety, or to manage a later procedure. Oral opiate analgesics have shown minimal effect on pain compared to placebo and cause more side effects including nausea (Micks 2012). IV sedation may be offered in some settings for patients who request more analgesia, although some medical conditions, monitoring, or facility limitations preclude moderate or deep sedation.
|PREFERRED ANESTHESIA METHODS
Preferred method of anesthesia for first-trimester
surgical abortion cases performed by responding
NAF clinics (n=110). For uterine aspiration,
local anesthesia with supplemental oral or IV
medication is the most frequently used approach
CONTINUUM OF SEDATION LEVEL
Various approaches to pain management may be offered to patients, depending on the clinical situation and resources. Below is a short summary of the levels of sedation, examples of medications used, and the associated risks.
|Level of Sedation||Example||Responsiveness||Airway||Spontaneous
|Minimal (Anxiolysis)||Oral lorazepam
to verbal stimulation
|Moderate “Conscious Sedation”||Fentanyl 50-100 mcg
Midazolam 1-3 mg IV
|Purposeful response to verbal or tactile stimulation||No intervention required||Adequate||Usually maintained|
|Deep||Add propofol or higher doses of meds used for moderate sedation||Purposeful response following repeated or painful stimulation||Intervention may be required||May be inadequate||Usually maintained|
|General Anesthesia||Propofol or other medications||Unarousable even with painful stimuli||Intervention often required||Frequently inadequate||May be impaired|
Adapted from Continuum of Depth of Sedation: Definition of GA and levels of Sedation / Anesthesia, 2014, ASA.
- When moderate sedation is used, a person trained to monitor respiratory, cardiovascular and level of consciousness must be present, other than the provider.
- The personnel administering moderate sedation must recognize that conscious sedation may lead to deep sedation with hypoventilation, and be prepared to provide respiratory support.
- Pulse oximetry should be used to enhance monitoring.
- IV access should be considered.
- The patient should be checked frequently for verbal responsiveness.
- A licensed airway manager should care for patients with severe systemic disease
- When moderate sedation is used, monitoring must be of a degree that can be expected to detect the respiratory effects of the drugs being used.
- The practitioner administering deep sedation or general anesthesia must be certified according to applicable local, hospital, and state requirements.
Opioid use and dependence is a growing problem in the U.S. (CDC 2013). Some patients may have a tolerance to opioid medications or may be on medically supervised opioid maintenance therapy (OMT), or opioid antagonist therapy with medications that interact with opiate pathways. OMT medications include methadone, a full agonist, and buprenorphine (e.g. Suboxone, buprenorphine-naloxone), a partial agonist (SAMHSA 2015). Antagonist therapies include Vivitrol, a depo naltrexone injection, and oral naltrexone.
For opioid tolerant patients, the goal of pain management continues to be provision of adequate analgesia during the procedure. Here are some general principles (SAMHSA 2015, Ries 2014, Huxtable 2011, and Alford 2006):
- Recognize that uterine aspiration can be painful but brief. Short acting pain medications are typically used, and higher doses of medication may be required.
- Do not worry about worsening tolerance in the setting of procedural pain.
- Patients with tolerance may worry that pain will not be adequately controlled, which can worsen their acute pain. Empathize and reassure them appropriately.
- Do not forget to utilize other ways to alleviate pain, such as NSAIDs, local anesthetic breathing, visualization techniques, and a support person in the room.
- Determine dosing by monitoring reported pain, alertness, and respiratory rate.
- Short acting, high affinity opioids like fentanyl or hydromorphone (Dilaudid) are effective and safe for repeated dosing; however, any opioid can be used.
- Those on OMT should continue their medications as prescribed.
- As buprenorphine is a partial agonist with high affinity for opioid receptors, or naltrexone, an opioid antagonist, pain control for patients on it can be difficult. Patients may need a much larger opioid dose or a temporary increase in buprenorphine, during a procedure.
- Patients on OMT can be given a short-term (1-3 days) opiate prescription if indicated, with an OMT clinic follow up within that time frame. The expected duration of their pain from uterine aspiration is the same as patients not on OMT.
- OMT and naltrexone prescribers can often provide guidance for acute pain control, and should know that their patient received other opioids. Communicate with the prescribing clinic or physician if possible, or offer a note documenting the opioids received under your care.
PROVIDING EFFECTIVE LOCAL ANESTHESIA
|A common approach is to inject 1-2 mL at 12 o’clock for the tenaculum, and then inject at 4 and 8 o’clock as depicted above to target paracervical innervation. Other approaches are to inject at 2 and 10 o’clock, or 3 and 9 o’clock. Image from Vidaeff 2016.|
INJECTION TIPS AND TECHNIQUES
- Paracervical block is effective at reducing pain regardless of gestational age, although it can also be painful at the time of injection (Renner 2012).
- Injection locations and techniques vary by provider.
- Reported pain scores during dilation and aspiration are improved with buffered lidocaine and deep injections (1.5 to 3 cm) in a Cochrane review (Renner 2010).
- It is inconclusive whether a 3-min wait time between PCB and cervical dilation provides noninferior pain control for first trimester surgical abortion. However, a four-site PCB appeared to be superior to a two-site PCB (Renner 2016).
- Some use a cough technique to distract during injection, but data are limited.
- Local anesthetics block nerve impulses, although physical pressure on nerves due to volume injected also provides analgesic effect. Saline has slightly less effect than lidocaine (Chanrachakul 2001, Miller 1996).
- Adding ketorolac to block decreased pain of dilation, but not overall pain (Cansino 2009).
- No evidence suggests one anesthetic is superior but options are reviewed below.
|Bupivicaine (Marcaine)||Strong||Moderate (up to 20 min)||Long (3-6 h)|
|Lidocaine (Xylocaine)||Medium||Fast (4-7 min)||Moderate (1-2 h) (~3 h with epinephrine)|
|Mepivicaine (Carbocaine)||Medium||Fast (4-7 min)||Moderate (3 h)|
|Chloroprocaine (Nesacaine)||Weaker||Fastest||Short (30 min) 25 sec half life|
TIPS TO MINIMIZE SYSTEMIC ABSORPTION
The maximum lidocaine dose recommended in pregnancy is 200 mg [achieved for example, by giving 20 ml of 1% lidocaine (10 mg/ml)].
When injected (inadvertently) intravenously at moderate concentrations, patients may have peri-oral tingling, dizziness, tinnitus, metallic taste or irregular/slow pulse. At higher concentrations, they may have muscular twitching, seizure, cardiac arrhythmias, unconsciousness, and even death (Paul 2009).
- Minimize direct intravascular injection and excessive anesthetic dosing.
- Use a combination of superficial (1 cm) and deep injections (3 cm).
- Move the needle while injecting (superficial to deep) OR aspirate before injecting.
- Use a dilute concentration (using 0.5% lidocaine or diluting with saline)
- Use a vasoconstrictor mixed with the anesthetic to slow systemic absorption.
One Possible Mixture for Preparation of Anesthetic
- Take 50 ml vial of 0.5% or 1% lidocaine and draw off 5 cc (save or discard)
- Add 2-4 units (0.1-0.2 ml) of vasopressin
- Add 5 ml sodium bicarbonate (8.4%) as buffer
- About 20 ml of mixture is usually adequate
Some add atropine to above mixture for vasovagal prevention (recommended dose 2 mg / 50 ml).
UNIVERSAL PRECAUTIONS PERTAINING TO UTERINE ASPIRATION
Universal precautions are designed to prevent transmission of blood-borne pathogens when providing health care.
- Wear gloves and protective eye gear when working with body fluids (i.e. injection, procedure, handling of tissue or contaminated instruments).
- Avoid recapping contaminated needles, and place sharps immediately in a puncture-resistant container for disposal.
- If there is a blood exposure, tell your supervisor. Information is available through the National Clinicians’ Post-Exposure Prophylaxis Hotline, or OSHA’s Bloodborne Pathogens and Needlestick Prevention site.