TC02 Obese Women Using It Morphine vs PCA IV Hydromorphone for Post-Cesarean Analgesia

Obesity Clinical Trial

Official title:

Randomized Controlled Trial Evaluating the Transcutaneous Carbon Dioxide Measurements in Obese Women Using Intrathecal Morphine Versus Patient-Controlled Intravenous Hydromorphone for Post-Cesarean Analgesia

Clinical Trial Details — Status: Withdrawn

Administrative data

• NCT number: NCT03282669
• Other study ID #: STU00203985
• Status: Withdrawn
• Phase: Phase 4
• Start date: August 2019
• Est. completion date: December 2021

Study information

• Verified date: May 2022
• Source: Northwestern University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Cesarean deliveries are the most commonly performed surgery in the United States and account for 32.9% of all births.8,9 The ASA recommends the use of neuraxial opioids of post-cesarean analgesia partly because respiratory depression in the obstetric population, as measured by intermittent respiratory rate and pulse oximetry, is reported to be low (0-1.2%).10,11 Respiratory depression lacks a standard definition,12 but the most sensitive means of detecting respiratory depression is hypercapnia.1,3 Two recent studies using continuous hypercapnia (>50mmHg PaCO2) monitoring demonstrated higher rates of respiratory depression (17.8-37%) in healthy, non-obese women receiving intrathecal opioids for post-cesarean analgesia.13,14 In addition, supplemental opioids are required in the majority of women receiving intrathecal morphine and may increase the risk of respiratory depression.11,14 Anesthesiologists debate whether neuraxial opioids or intravenous patient controlled opioid analgesia (PCA) are the safest practice for postoperative analgesia in obese parturients following cesarean delivery. The ASA recommendations to employ neuraxial analgesia post-cesarean delivery does not differentiate between non-obese and obese women who now make up 30.3% in US women of child-bearing age.2 Obesity has been described as a risk factor for respiratory depression in those receiving opioids via any route of opioid administration,11,15, 17 but whether obesity itself is the risk factor or associated co-morbidities such as sleep apnea is debated.

Studies are conflicting whether intrathecal opioids or patient controlled intravenous opioids cause more respiratory depression. Several studies have documented the incidence of respiratory depression with IV PCA; the rates range from 0.19% to 5.2%, which are equivalent or higher than those reported for intrathecal opioids. (Hagle 16). Dalchow et al. demonstrated higher rates of hypercapnia in patients receiving intrathecal opioid compared with those receiving intravenous opioid via patient controlled analgesia in nonobese women following cesarean delivery. (Dalchow)

The Topological Oscillation Search with Kinematical Analysis (TOSCA) monitor allows a noninvasive method to measure transcutaneous carbon dioxide levels, with relative accuracy compared to arterial carbon dioxide monitoring.4-7 No studies have examined transcutaneous carbon dioxide levels in obese women following cesarean delivery using any form of postoperative analgesia. The investigators propose a randomized controlled trial using continuous transcutaneous carbon dioxide monitoring to evaluate the degree of respiratory depression in obese women receiving neuraxial opioid compared to intravenous opioid via PCA for post-cesarean analgesia.

Two studies have demonstrated high rates of hypercapnia in non-obese women following administration of intrathecal morphine for cesarean delivery in the postpartum period. (Dalchow, Bauchat) Dalchow et al. demonstrated higher rates of hypercapnia in women receiving intrathecal diamorphine than intravenous morphine delivered via patient controlled analgesia. It is unclear whether intrathecal morphine causes more or less respiratory depression than intravenous opioid delivered via patient-controlled analgesia in obese women.

This study will add to the understanding of respiratory function in the immediate postpartum period in obese women using opioids via intrathecal or intravenous routes. This study will better inform guidelines for the postpartum analgesic route of choice in the obese obstetric population and allow the investigators to make recommendations for the detection and prevention of respiratory depression after opioid administration in the obstetric population.

Objective is to examine the transcutaneous carbon dioxide levels in obese women using either intrathecal morphine or intravenous patient-controlled hydromorphone for post-cesarean analgesia.

The hypothesis is carbon dioxide levels will be significantly higher in obese women receiving intrathecal morphine versus obese women receiving intravenous patient controlled intravenous hydromorphone.

Recruitment information / eligibility

• Status: Withdrawn
• Enrollment: 0
• Est. completion date: December 2021
• Est. primary completion date: December 2021
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

• Term (=37 week's gestation)

• Healthy

• ASA class 2-3

• BMI =40kg/m2 scheduled for elective cesarean section whose anesthetic plan is for neuraxial anesthesia (spinal or combined-spinal epidural technique)

Exclusion Criteria:

• Women with ASA >3,

• BMI <40 kg/m2

• Allergy to any of the medications used for pain control

• Contraindication to the spinal anesthetic technique

• Known sleep apnea or other sleep disordered breathing

• Regular use of other medications that cause respiratory depression (ie. benzodiazepines).

Related Conditions & MeSH terms

• Obesity
• Pain, Postoperative
• Pulmonary Valve Insufficiency
• Respiratory Insufficiency

Intervention

Drug:
• Intrathecal Morphine
Intrathecal Morphine administered in the operating room.
• Intravenous hydromorphone
Intravenous hydromorphone administered via IV in the post operative area.

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
Northwestern University

References & Publications (4)

Lee LA, Caplan RA, Stephens LS, Posner KL, Terman GW, Voepel-Lewis T, Domino KB. Postoperative opioid-induced respiratory depression: a closed claims analysis. Anesthesiology. 2015 Mar;122(3):659-65. doi: 10.1097/ALN.0000000000000564. — View Citation

McCormack JG, Kelly KP, Wedgwood J, Lyon R. The effects of different analgesic regimens on transcutaneous CO2 after major surgery. Anaesthesia. 2008 Aug;63(8):814-21. doi: 10.1111/j.1365-2044.2008.05487.x. — View Citation

Ogden CL, Carroll MD, Kit BK, Flegal KM. Prevalence of childhood and adult obesity in the United States, 2011-2012. JAMA. 2014 Feb 26;311(8):806-14. doi: 10.1001/jama.2014.732. — View Citation

Practice Guidelines for the Prevention, Detection, and Management of Respiratory Depression Associated with Neuraxial Opioid Administration: An Updated Report by the American Society of Anesthesiologists Task Force on Neuraxial Opioids and the American So — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Incidence of hypercapnia	Incidence of hypercapnia (transcutaneous CO2 levels >50mmHg) in the intrathecal morphine versus patient controlled intravenous morphine groups	24 hours post delivery
Secondary	Opioid consumption	Amount of opioids used during the time from delivery to 24 hours post delivery	24 hours post delivery
Secondary	NSAID consumption	Amount of NSAID's used during the time from delivery to 24 hours post delivery.	24 hours post delivery
Secondary	Respiratory rate	Hourly respiratory rates for the first 12 hours then every 2 hours for the next 12 hours.	24 hours post delivery
Secondary	Sedation scores	Sedation scores as scored on the Richmond Agitation and Sedation Scale at 2 hours, 6 hour and 12 hours post delivery.	delivery to 12 hours post delivery
Secondary	Pain Scores	Pain scores on a scale of 0 (low)-10 (high) will be documented every hour for the first 24 hours after delivery.	24 hours
Secondary	Pulse oximetry	Pulse oximetry will be collected using the transcutaneous Co2 monitor for 24 hours after deliuvery.	24 hours post delivery