The Impact of Using Different Spinal Needle Sizes on the Efficacy of the Dural Puncture Epidural Block

• 81 patients primigravida parturients (ASA II) in active labor
• uncomplicated pregnancy
• Cephalic presentation
• Cervical dilatation <5 cm

Exclusion criteria:

• Allergy to local anesthetics.
• Bleeding disorders
• Low platelet count
• Local or systemic sepsis
• Prior surgery in lumbosacral spine
• Patient's refusal.

Eighty-one patients meeting the inclusion criteria were randomly divided into three equal groups:

Group CE (n=27): Conventional epidural. Group DPE-25 (n=27): Dural puncture epidural with 25-gauge spinal needle. Group DPE-27 (n=27): Dural puncture epidural with 27-gauge spinal needle.

Randomization was done by computer generated numbers and concealed by serially numbered, opaque and sealed envelopes. The details of the series were unknown to the investigators and the group assignment was kept in a set of sealed envelopes, each bearing only the case number on the outside.

Full medical and surgical history were taken. Laboratory investigations were revised. Visual analogue scale was educated to the patient before the start of the operation.

One liter of lactated Ringer's solution was infused IV over 15 min during the neuraxial procedure.

The procedure was performed in the seated position. Parturients with VAS < 5 were excluded.

The procedure was performed by a senior anesthesia resident.

Before administering medications through the epidural catheter, subarachnoid, intravascular and subdural placement had to be ruled out.

After 5 min of the first initial bolus dose, adequacy of analgesia was assessed.

Analgesia was considered adequate if VAS score is ≤3. Onset of analgesia was defined as from time of first bolus dose to time of achieving VAS ≤3.

Patient with VAS score >3; considered failed block and were excluded from the study.

Analgesia was evaluated by a blinded observer assessing visual analog scale (VAS) pain scores, onset of analgesia, sensory level, and motor blockade.

The primary outcome was the onset of analgesia (defined as duration from injection of the first initial epidural bolus to attainment of VAS <3).

Other data collected are:

1. Patients' demographic data.
2. Obstetrics data.
3. Onset of analgesia (attainment of VAS <3).
4. HR and MABP (baseline, every 5 minutes until 15 mins, a every 15 mins till 1 hour and then every 1 hour till delivery).
5. Visual analogue scale (VAS) with hemodynamics.
6. Assessment of sensory level after 30 mins of the block.
7. Assessment of Sacral block during the 1st 30 minutes.
8. Assessment of motor block through the modified bromage scale
9. Occurrence of side effects as: Hypotension, bradycardia, nausea, vomiting and pruritis ,PDPH, nerve injury.