Ultrasound-Guided Landmark and Epidural Site Pain

A Prospective Randomized Clinical Trial to Study the Effect of Pre-Epidural Ultrasound Examination on Epidural Insertion Site Pressure Sensitivity in Parturient

Historically, women who have chronic back pain after pregnancy have attributed the cause to the epidural procedure. While many studies have shown no greater incidence of generalized post-partum back pain in those who received an epidural, no studies have measured localized pressure sensitivity at the epidural insertion site. Short-term pressure sensitivity might limit patient's mobility and activities in the post-partum period. Understanding the factors that increase insertion site pressure sensitivity will allow the investigators to modify epidural placement technique in order to minimize this effect.

Few studies have examined how epidural placement changes localized sensation at the epidural insertion site. This study will be the first study to quantitatively measure sensation at the epidural insertion site. The investigator will assess localized pressure sensitivity with an algometer. An algometer is a hand-held device commonly used by neurologist to detect sensory deficits and measures the pressure sensitivity threshold in a 1-cm diameter circular area. Ultrasound (US) pre-procedural examination provides more accurate landmarks for the placement of epidural catheters. The investigator will determine if an US examination prior to epidural placement reduces localized pressure sensitivity. The investigator will also determine if there are correlations between the participants characteristics and/or comorbidities and increased pressure sensitivity at the insertion site.

US-epidural SVD group - participants who received US examination prior to epidural placement. The purpose of this group is to determine if US derived landmarks reduce pressure sensitivity

US sham- epidural SVD group- participants who received US examination process but with the monitor turned off.

Spontaneous vaginal delivery without an Epidural group The purpose of the control group is to serve as a baseline.

participants who received US examination prior to epidural placement. The purpose of this group is to determine if US derived landmarks reduce pressure sensitivity.

participants who received US examination process but with the monitor turned off. The purpose of this group is to determine if the standard of care epidural placement technique will increase pressure sensitivity at the insertion site. The purpose of this group will also be to reduce the placebo effect from the US exam and to maintain blinding of the patient to their group status (US epidural or US sham epidural).

Spontaneous vaginal delivery without an Epidural The purpose of the control group is to serve as a baseline (or a measure of normal). The control participant's measurement will be compared to those that did receive treatments (either epidural alone or ultrasound and epidural). This information will tell the investigator how many women have back pain after spontaneous vaginal delivery. Participant must meet the inclusion requirements and not meet any of the exclusion requirements

Epidural pressure sensitivity was monitored 10 minutes prior to epidural insertion and then for 10 minutes on each day after epidural removal for 3 days.

The investigator will review the chart to see if the participant used of induction medication (answer yes will be recorded)

The chart review will determine the use of induction medication immediately prior to the epidural placement

The investigator will review the chart to see if the participant required opioids during labor (yes will be recorded)

The investigator will ask the participant if they have had back pain lasting longer than one week during pregnancy? (yes answer will be recorded)

Participants will be asked if they have had back pain for longer than a week immediately prior to epidural placement

The investigator will count the number epidural needle repositions during the epidural placement (whole number)

The investigator will count the number epidural needle insertions during the epidural placement (whole number)

Inclusion Criteria: pregnant with term (37 - 41 weeks) singleton gestation active labor history of normal pregnancy request an epidural age between 18 - 35 years old able to understand the protocol and provide voluntary, written, informed consent. Exclusion Criteria: history of spinal surgery scoliosis epidural or spinal placement within the last 5 days neuropathic pain disorders chronic opioid use Texas Department of Criminal Justice patient placental percreta placental increta placenta accreta preeclampsia eclampsia