Intra-operative Feed Back on Traction Force During Vacuum Extraction: Safe Vacuum Extraction Alliance

Hypoxic Ischemic Encephalopathy Clinical Trial

— SVEA  

Official title:

Intra-operative Feed Back on Traction Force During Vacuum Extraction: a Randomized Control Study of Mid and Low Metal Cup Deliveries.

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03071783
• Other study ID #: KI-Clintec-SVEA
• Status: Completed
• Phase: N/A
• Start date: April 1, 2016
• Est. completion date: June 15, 2018

Study information

• Verified date: March 2019
• Source: Karolinska Institutet
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The objective of the clinical investigation is to test whether intra-operative traction force feed back during vacuum extraction leads to a significant decrease in incidence of brain damage in neonates.

By randomization, half of the vacuum extraction patients will be assigned to delivery using a new intelligent handle for vacuum extractions, and half will be assigned to conventional method without traction force measurement.

Description:

The most common indications for vacuum extraction are dystocia and/or fetal asphyxia. The safety of assisted vaginal delivery with vacuum extraction has been discussed since its introduction almost fifty years ago. Serious complications such as asphyxia, intracranial hemorrhage and seizures are overrepresented at vacuum extraction compared to spontaneous vaginal delivery.

Little has been done to improve the procedure since the introduction. Safety measures recommended include restricting total time and number of pulls, a full 34 week gestation, and station of the head at the spines or below. A general advice is also to avoid excessive traction force. There is no general agreement to what a safe traction force might be. With exceeding force there seems to be an increased risk for rupture of the sagittal sinus and tearing of the falx at its attachment to the tentorium. Furthermore, when the fetal head is becoming exceedingly elongated and flattened, and as the cup pops off it might cause damage to the brain and blood vessels.

During the procedure the obstetrician is under significant stress and the subjective element of the evaluation of traction force is a concern. The difficult decision of whether to continue a heavy extraction or abort the operation is made under stressful conditions and based mostly on subjective impressions.

To provide the obstetrician with more objective information, the investigators developed a new device consisting of an intelligent handle hooked to the chain of a regular metal cup.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 800
• Est. completion date: June 15, 2018
• Est. primary completion date: June 15, 2018
• Accepts healthy volunteers: No
• Gender: Female
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Medical or social reasons for vacuum extraction with a metal cup, gestational age =37+0 weeks, singleton, cephalic

Exclusion Criteria:

• Multiple pregnancy, breech presentation, gestational age <37+0

Related Conditions & MeSH terms

• Brain Diseases
• Brain Ischemia
• Hematoma
• Hypoxia-Ischemia, Brain
• Hypoxic Ischemic Encephalopathy
• Neonatal Convulsions
• Seizures
• Subgaleal Hematoma

Intervention

Device:
• Vacuum extraction intelligent system
Vacuum extraction intelligent system - this is the intervention

Locations

Country	Name	City	State
Sweden	Karolinska University Hospital	Stockholm

Sponsors (1)

Lead Sponsor	Collaborator
Karolinska Institutet

Country where clinical trial is conducted

Sweden, 

References & Publications (5)

MALMSTROM T. The vacuum extractor, an obstetrical instrument. I. Acta Obstet Gynecol Scand Suppl. 1957;36(suppl 3):5-50. — View Citation

Moolgaoker AS, Ahamed SO, Payne PR. A comparison of different methods of instrumental delivery based on electronic measurements of compression and traction. Obstet Gynecol. 1979 Sep;54(3):299-309. — View Citation

Pettersson K, Ajne J, Yousaf K, Sturm D, Westgren M, Ajne G. Traction force during vacuum extraction: a prospective observational study. BJOG. 2015 Dec;122(13):1809-16. doi: 10.1111/1471-0528.13222. Epub 2015 Jan 5. — View Citation

Towner DR, Ciotti MC. Operative vaginal delivery: a cause of birth injury or is it? Clin Obstet Gynecol. 2007 Sep;50(3):563-81. Review. — View Citation

Whitby EH, Griffiths PD, Rutter S, Smith MF, Sprigg A, Ohadike P, Davies NP, Rigby AS, Paley MN. Frequency and natural history of subdural haemorrhages in babies and relation to obstetric factors. Lancet. 2004 Mar 13;363(9412):846-51. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Composite neonatal brain damage	Composite consists of: Hypoxic ischemic encephalopathy (HIE), intracranial hemorrhage (ICH), seizures, perinatal mortality and subgaleal hematoma as routinely diagnosed in patient chart	From start of extraction through 28 days after delivery (or until discharge from the hospital)