Adding Dexmedetomidine or Clonidine to Spinal Anesthesia for Cesarean Delivery

Overview

This study will examine whether addition of dexmedetomidine or clonidine (two alpha-2 adrenergic agonists) will improve the comfort of patients during spinal anesthesia for cesarean delivery. When added to standard spinal anesthesia consisting of bupivacaine (a local anesthetic) and fentanyl and morphine (two opioids), these medications may decrease some of the pulling/tugging/pressure sensations that patients sometimes feel during cesarean delivery, may prolong the anesthetic time, and may decrease postoperative pain.

Detailed description

While spinal anesthesia almost always creates a reasonably comfortable operative/birth experience, a significant proportion of women do experience significance "pressure" or "pulling" and some do have sensations described as painful during the operation. This has received increased interest in both the medical and lay press in recent years. The main medication in a spinal anesthetic is the local anesthetic, usually bupivacaine, but a variety of adjuvants can and are used to improve the analgesia and decrease sensation (or increase the time period of effectiveness) of the anesthetic. Opioids (usually fentanyl or sufentanil for intraoperative benefits and morphine for postoperative analgesia) are very commonly added to spinal anesthetics for cesarean delivery in the United States.

Somewhat less commonly, but increasingly, alpha-2 adrenergic agonists (clonidine or dexmedetomidine), which have sedative and analgesic properties (mostly analgesic when given into spinal fluid) are added in an attempt to improve the intraoperative experience and/or lengthen the time the block is effective. These adjuvants, although not approved specifically for this use in spinal anesthesia, have become more widely used in spinal anesthesia, including for cesarean delivery, and have been mentioned/recommended in recent statements by the American Society of Anesthesiologists for use when additional or improved analgesia may be needed or desired.

The quality of the studies of intrathecal dexmedetomidine as part of spinal anesthesia for cesarean delivery is quite poor. This study will investigate whether clonidine or dexmedetomidine, when added to a spinal anesthetic containing bupivacaine/fentanyl/morphine, will improve intraoperative analgesia/anesthesia, decrease unwanted sensation, and assess what the other effects will be (prolongation of sensory and motor block, effects on blood pressure, other side effects).

Interventions

• Drug Clonidine
  30 mcg Clonidine will be given by intrathecal administration
• Drug Dexmedetomidine
  4 mcg Dexmedetomidine will be given by intrathecal administration

Primary outcome measures

• Incidence of intraoperative discomfort [Time frame: during cesarean surgery]

Secondary outcome measures (7)

• Obstetric Quality of Recovery (ObsQoR-10) Score [Time frame: 0-6, 6-12, 12-24, 24-48 hours after surgery]
• Length of motor and sensory block [Time frame: 2-5 hours]
• Incidence of Hypotension [Time frame: first 20 minutes after spinal, or until delivery]
• Phenylephrine use [Time frame: 20 minutes]
• PACU side-effects/events [Time frame: 2-3 hours postop]
• Blood pressure [Time frame: ~ 20 minutes from spinal injection]
• Additional vasopressor use [Time frame: From Spinal anesthesia to 20 minutes or delivery (whichever comes first)]

Eligibility criteria

Inclusion criteria

• Pregnant women undergoing cesarean delivery with spinal anesthesia

Exclusion criteria

• Significant cardiovascular, psychiatric or respiratory disease
• using opioids or with chronic pain syndrome
• Multiple gestation
• BMI >40 kg/m2
• Quaternary or greater cesarean
• < 37 weeks gestation
• Non-English or Spanish speaking
• planned vertical skin incision
• planned vertical (classical) uterine incision
• allergy to clonidine, dexmedetomidine or other study drug

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Factorial

Masking

Quadruple blind

Primary purpose

Treatment

Study locations

United States · 1 center

• Columbia University Irving Medical Center/NewYork Presbyterian Hospital — New York

Publications

• New York Times, Podcast, The Retrievals, Season 2, episodes 1-4.
• Orbach-Zinger S, Azem K, Bar M, Heesen P, Kozuch D, Furman D, Cohen R, Kashkush A, Izyumsky D, Fein S, Frenkel A, Shavialiou A, Binyamin Y. Intra-operative sensation during caesarean delivery under neuraxial anaesthesia: A prospective cohort study mapping sensory experiences. Eur J Anaesthesiol. 2026 Mar 1;43(3):217-225. doi: 10.1097/EJA.0000000000002317. Epub 2025 Nov 11. PMID 41221837
• Takalo E, Karpala M, An X, Cobb B, Zhao S, Bari R, Hylton M, Grant S, Schoenherr J. Intrathecal dexmedetomidine for cesarean delivery and postoperative outcomes: a single-center retrospective cohort study (2019-2020). Int J Obstet Anesth. 2026 Feb;65:104819. doi: 10.1016/j.ijoa.2025.104819. Epub 2025 Nov 14. PMID 41265256
• Fernandes HS, Bliacheriene F, Vago TM, Corregliano GT, Torres ML, Francisco RP, Ashmawi HA. Clonidine Effect on Pain After Cesarean Delivery: A Randomized Controlled Trial of Different Routes of Administration. Anesth Analg. 2018 Jul;127(1):165-170. doi: 10.1213/ANE.0000000000003319. PMID 29596102

Identifiers

NCT: NCT07567495 · ACYY0438

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗