Effect of Paracervical Block Volume on Pain Control for Dilation and Curettage.o

Assessing the Effect of Paracervical Block Volume on Pain Control for Dilation and Curettage: a Randomized Controlled Trial

The investigators are conducting a study on pain control for dilation and curettage (D&C). Participants are eligible to enroll if they are a planning to have a D&C in a participating clinic. The investigators are studying how different ratios of medication to liquid affect pain when injected around the cervix. Both potential methods use the same dose of medication, though researchers would like to know which one works better. To be in this study, participants must be over the age of 18 with an early pregnancy loss or undesired pregnancy measuring less than 12 weeks gestation undergoing D&C while awake in clinic.

Dilation and Curettage (D&C) is often performed in the first trimester for surgical abortion and management of miscarriage and can be painful for patients before and after the procedure. Most procedures are performed while the patient is awake or with minimal sedation in the clinic setting, and a key component of pain control is the paracervical block, or injecting lidocaine into the tissue around the cervix. A paracervical block with 20cc of 1% buffered lidocaine has been proven to provide superior pain control than a sham paracervical block. However, many providers often use similar doses of lidocaine in a higher volume to improve pain control. At University of California, San Diego (UCSD) and University of California, Los Angeles (UCLA), some providers routinely use a 20cc of 1% buffered lidocaine block and some routinely use a 40cc of 0.5% buffered lidocaine block. This practice has not been studied in a randomized controlled trial. The purpose of this study is to compare pain control during D&C with a 20cc 1% buffered lidocaine with vasopressin paracervical block compared to a 40cc 0.5% buffered lidocaine with vasopressin paracervical block. An inclusion criterion for this study is that patients must specifically be referred to family planning clinics at UCSD and UCLA for an in-clinic D&C. Therefore, the D&C is a required procedure for both study groups. The only difference in care between the study groups will be which paracervical block they receive.

This is a double center, randomized, 2 arm (1:1), single blinded clinical trial comparing pain control at the time of cervical dilation with two different paracervical blocks in women undergoing D&C in the first trimester for either surgical abortion or miscarriage management.

The study coordinator, who will be blinded to the intervention, will pick the designated sealed, opaque envelope containing the type of paracervical block and hand it to the physician performing the procedure. The physician will then open the envelope and prepare the designated paracervical block, as it is standard practice for physicians to prepare their own paracervical blocks prior to performing any D&C in-clinic. The paracervical block will contain 2U Vasopressin, 2cc of 8.4% sodium bicarbonate, and either 1% lidocaine or 0.5% lidocaine, depending on the study group. The physician will bring the paracervical block into the clinic room where the procedure will be performed on a covered tray. The physician will perform the standardized procedure for the D&C, and the study coordinator will assess pain control during the procedure.

40c buffered 0.5% lidocaine with 2 units of vasopressin paracervical block with dilation and curettage under minimal sedation

20cc 1% lidocaine with 2 units of vasopressin paracervical block with dilation and curettage under minimal sedation

Women undergoing D&C in the first trimester for either surgical abortion or miscarriage management will receive 40cc buffered 0.5% lidocaine with 2 units of vasopressin paracervical block before cervical dilation.

Women undergoing D&C in the first trimester for either surgical abortion or miscarriage management will be randomly assigned to receive 20cc 1% lidocaine with 2 units of vasopressin paracervical block before cervical dilation.

Distance (mm) from the left of the 100-mm Visual Analog Scale (VAS) (reflecting magnitude of pain) recorded at time of cervical dilation. Pain will be assessed using a 100 mm visual analogue scale with the anchors 0 = none, 100 mm = worst imaginable.

Once during the procedure on the day of recruitment, approximately one minute. During procedure at time of cervical dilation.

Distance (mm) from the left of the 100-mm Visual Analog Scale (VAS) (reflecting magnitude of pain) recorded immediately after uterine aspiration. Pain will be assessed using a 100 mm visual analogue scale with the anchors 0 = none, 100 mm = worst imaginable.

Once during the procedure on the day of recruitment, approximately 1 minute. During procedure immediately after uterine aspiration.

Distance (mm) from the left of the 100-mm Visual Analog Scale (VAS) (reflecting magnitude of pain) recorded 10 minutes after the completion of the procedure. Pain will be assessed using a 100 mm visual analogue scale with the anchors 0 = none, 100 mm = worst imaginable.

Distance (mm) from the left of the 100-mm Visual Analog Scale (VAS) (reflecting magnitude of pain) recorded after the procedure reflecting the overall pain felt during the procedure. Pain will be assessed using a 100 mm visual analogue scale with the anchors 0 = none, 100 mm = worst imaginable.

Inclusion Criteria: Women over the age of 18 presenting to UC San Diego and UC Los Angeles Undesired pregnancy or missed abortion < 11 weeks 6 days gestation Must speak English or Spanish Desire surgical termination of pregnancy or management of miscarriage in clinic Exclusion Criteria: Women with a diagnosis of inevitable or incomplete abortion Desire for general anesthesia or IV sedation Chronic pain conditions Any medical comorbidities that are a contraindication to performing the procedure in the clinic setting Allergy to or refusal of ketorolac, oral Versed, or a paracervical block If they have taken any pain medications the day of presentation to clinic If they have taken Misoprostol the day of presentation to clinic

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