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Transversus Abdominis Plane (TAP) Block for Cesarean Section

Information source: University of Washington
ClinicalTrials.gov processed this data on August 20, 2015
Link to the current ClinicalTrials.gov record.

Condition(s) targeted: Hyperalgesia, Secondary

Intervention: Bupivacaine Placebo (Drug); Clonidine Placebo (Drug); Bupivacaine (Drug); Clonidine (Drug)

Phase: N/A

Status: Terminated

Sponsored by: University of Washington

Official(s) and/or principal investigator(s):
Ruth Landau, MD, Study Chair, Affiliation: University of Washington
Laurent Bollag, MD, Principal Investigator, Affiliation: University of Washington


The purpose of this study is to determine whether a transversus abdominis plane (TAP) block with Clonidine added to the injectate (Clo-TAP) performed approximately 2hrs after the cesarean section (CS) will decrease the amount of postoperative hyperalgesia and ultimately reduce post-CS chronic pain.

Clinical Details

Official title: Transversus Abdominis Plane (TAP) Block for Cesarean Section

Study design: Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver), Primary Purpose: Prevention

Primary outcome: To determine which of three different TAP formulations (Placebo, TAP, Clo-TAP) has the most beneficial effect on the postoperative area of hyperalgesia 48hrs after the start of the cesarean section.

Secondary outcome:

To determine which of three different TAP formulations has the most beneficial effect on the postoperative area of hyperalgesia 24 hrs after the start of the CS

To determine which of the three different TAP groups has the most beneficial effect on the postoperative amount of static hyperalgesia 24 and 48hrs after the start of the CS

To evaluate pain scores at rest and during movement at 6, 12, 18, 24, 36 and 48hrs after the surgery

To evaluate the time it takes for a woman to ask for the first analgesic medication after the surgery

To evaluate postoperative morphine consumption (or equivalent of morphine) during the first 48hrs after the surgery

To evaluate the correlation between preoperative mechanical temporal summation (mTS) and amount of hyperalgesia and postoperative pain

To evaluate postoperative side effects such as postoperative nausea and vomiting (PONV), constipation, urinary retention, de-ambulation and motricity

To evaluate chronic pain at 3, 6 and 12 months post-surgery by phone with the Short-Form McGill Pain Questionnaire 2 (SF-MPQ-2)

To study selected candidate genes related to postoperative pain and analgesics

Detailed description: Acute severe pain after cesarean section (CS) occurs more often than is thought and 10-15% of the women having a cesarean section develop chronic pain (Kehlet et al. 2006). With over 1. 3 million cesarean deliveries per year in the US, this is bound to create a significant health problem. One way to address this health burden is to refine techniques that may help control the pain women experience after CS and ultimately reduce the potential to develop chronic pain. The purpose of this randomized, double-blinded study is to evaluate the ability of an established anesthetic technique called the transversus abdominis plane (TAP) block to reduce the amount of hyperalgesia women develop around their incision after CS. Measuring the amount of punctuate mechanical hyperalgesia is used as a tool to assess postoperative central sensitization (Lavand'homme et al. 2005), which contributes to postoperative acute pain. Since postoperative acute pain has been shown to be predictive of developing postoperative chronic pain (Eisenach et al. 2008; Yarnitsky et al. 2008), an effective TAP block could help diminish the incidence of chronic pain after CS. In addition, blood samples will be collected for future genetic analysis and we will test preoperatively for mechanical temporal summation (mTS) to evaluate CNS (central nervous system) sensitization and nociceptive system hyperexcitability and see if this correlates with the amount of hyperalgesia women develop around their incision after surgery. The primary aim of this study is to evaluate the benefits of two different solutions injected by TAP block technique on postoperative peri-incisional hyperalgesia.


Minimum age: 18 Years. Maximum age: 45 Years. Gender(s): Female.


Inclusion Criteria:

- non-laboring women who will benefit from and have clinically consented to a scheduled

or non-scheduled cesarean delivery under spinal anesthesia

- English speaking

- aged between 18 and 45 years

- BMI < 40

- ASA physical status class I or II

Exclusion Criteria:

- laboring women undergoing a non-scheduled cesarean delivery

- non-English speaking

- previous spinal surgery

- contraindications for neuraxial anesthesia

- allergy to local anesthetic, ultrasound conduction gel, or Clonidine

- history of chronic pain

- inability to receive intraoperative Toradol

Locations and Contacts

University of Washington, Seattle, Washington 98195, United States
Additional Information

Related publications:

Buchanan ML, Easterling TR, Carr DB, Shen DD, Risler LJ, Nelson WL, Mattison DR, Hebert MF. Clonidine pharmacokinetics in pregnancy. Drug Metab Dispos. 2009 Apr;37(4):702-5. doi: 10.1124/dmd.108.024984. Epub 2008 Dec 30.

Carvalho B, Angst MS, Fuller AJ, Lin E, Mathusamy AD, Riley ET. Experimental heat pain for detecting pregnancy-induced analgesia in humans. Anesth Analg. 2006 Nov;103(5):1283-7.

Duma A, Urbanek B, Sitzwohl C, Kreiger A, Zimpfer M, Kapral S. Clonidine as an adjuvant to local anaesthetic axillary brachial plexus block: a randomized, controlled study. Br J Anaesth. 2005 Jan;94(1):112-6. Epub 2004 Oct 29.

Eisenach JC, De Kock M, Klimscha W. alpha(2)-adrenergic agonists for regional anesthesia. A clinical review of clonidine (1984-1995). Anesthesiology. 1996 Sep;85(3):655-74. Review.

Gabriel JS, Gordin V. Alpha 2 agonists in regional anesthesia and analgesia. Curr Opin Anaesthesiol. 2001 Dec;14(6):751-3.

Kehlet H, Jensen TS, Woolf CJ. Persistent postsurgical pain: risk factors and prevention. Lancet. 2006 May 13;367(9522):1618-25. Review.

Landau R, Schiffer E, Morales M, Savoldelli G, Kern C. The dose-sparing effect of clonidine added to ropivacaine for labor epidural analgesia. Anesth Analg. 2002 Sep;95(3):728-34, table of contents.

Lavand'homme P. Postcesarean analgesia: effective strategies and association with chronic pain. Curr Opin Anaesthesiol. 2006 Jun;19(3):244-8. Review.

Lavand'homme P. Perioperative pain. Curr Opin Anaesthesiol. 2006 Oct;19(5):556-61. Review.

Lavand'homme P, De Kock M, Waterloos H. Intraoperative epidural analgesia combined with ketamine provides effective preventive analgesia in patients undergoing major digestive surgery. Anesthesiology. 2005 Oct;103(4):813-20.

Lavand'homme PM, Roelants F, Waterloos H, Collet V, De Kock MF. An evaluation of the postoperative antihyperalgesic and analgesic effects of intrathecal clonidine administered during elective cesarean delivery. Anesth Analg. 2008 Sep;107(3):948-55. doi: 10.1213/ane.0b013e31817f1595.

Lavand'homme PM, Roelants F, Waterloos H, De Kock MF. Postoperative analgesic effects of continuous wound infiltration with diclofenac after elective cesarean delivery. Anesthesiology. 2007 Jun;106(6):1220-5.

Marhofer P, Greher M, Kapral S. Ultrasound guidance in regional anaesthesia. Br J Anaesth. 2005 Jan;94(1):7-17. Epub 2004 Jul 26. Review.

McCartney CJ, Duggan E, Apatu E. Should we add clonidine to local anesthetic for peripheral nerve blockade? A qualitative systematic review of the literature. Reg Anesth Pain Med. 2007 Jul-Aug;32(4):330-8. Review.

McDonnell JG, Curley G, Carney J, Benton A, Costello J, Maharaj CH, Laffey JG. The analgesic efficacy of transversus abdominis plane block after cesarean delivery: a randomized controlled trial. Anesth Analg. 2008 Jan;106(1):186-91, table of contents. doi: 10.1213/01.ane.0000290294.64090.f3.

McDonnell JG, Laffey JG. Transversus abdominis plane block. Anesth Analg. 2007 Sep;105(3):883.

McDonnell JG, O'Donnell BD, Farrell T, Gough N, Tuite D, Power C, Laffey JG. Transversus abdominis plane block: a cadaveric and radiological evaluation. Reg Anesth Pain Med. 2007 Sep-Oct;32(5):399-404.

Mendez R, Eisenach JC, Kashtan K. Epidural clonidine analgesia after cesarean section. Anesthesiology. 1990 Nov;73(5):848-52.

Nikolajsen L, Sørensen HC, Jensen TS, Kehlet H. Chronic pain following Caesarean section. Acta Anaesthesiol Scand. 2004 Jan;48(1):111-6.

Ohel I, Walfisch A, Shitenberg D, Sheiner E, Hallak M. A rise in pain threshold during labor: a prospective clinical trial. Pain. 2007 Nov;132 Suppl 1:S104-8. Epub 2007 Jun 20.

Pan PH, Coghill R, Houle TT, Seid MH, Lindel WM, Parker RL, Washburn SA, Harris L, Eisenach JC. Multifactorial preoperative predictors for postcesarean section pain and analgesic requirement. Anesthesiology. 2006 Mar;104(3):417-25.

Parker RK, Connelly NR, Lucas T, Serban S, Pristas R, Berman E, Gibson C. Epidural clonidine added to a bupivacaine infusion increases analgesic duration in labor without adverse maternal or fetal effects. J Anesth. 2007;21(2):142-7. Epub 2007 May 30.

Weissman-Fogel I, Granovsky Y, Crispel Y, Ben-Nun A, Best LA, Yarnitsky D, Granot M. Enhanced presurgical pain temporal summation response predicts post-thoracotomy pain intensity during the acute postoperative phase. J Pain. 2009 Jun;10(6):628-36. doi: 10.1016/j.jpain.2008.12.009. Epub 2009 Apr 23.

Yarnitsky D, Crispel Y, Eisenberg E, Granovsky Y, Ben-Nun A, Sprecher E, Best LA, Granot M. Prediction of chronic post-operative pain: pre-operative DNIC testing identifies patients at risk. Pain. 2008 Aug 15;138(1):22-8. Epub 2008 Jan 8.

Starting date: November 2009
Last updated: September 20, 2013

Page last updated: August 20, 2015

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