Cerebrospinal Acid-base in Pregnant and Non-pregnant Fertile Women

Institute of Hospitalization and Scientific Care (IRCCS)

Status: Unknown

Conditions: Acid-Base Imbalance; Respiratory Alkalosis; Cerebrospinal Fluid; Pregnancy

Treatments: Diagnostic Test: Acid - Base characterization

Study type: Observational

Funder types: Other

Identifiers

NCT03496311

CSF acid-base in pregnancy

Details and patient eligibility

About

The third trimester of pregnancy is typically characterized by the development of a marked respiratory alkalosis. The possible role of pregnancy-induced variations of cerebrospinal fluid (CSF) acid-base characteristics on the development of hypocapnic alkalosis is still unknown.

Aim of this study is to characterize, according to Stewart's approach, the acid-base equilibrium of CSF and arterial plasma of pregnant women and compare the results with data obtained from fertile, non-pregnant women.

Full description

The reduction in plasma PCO2 correlates with gestational age and was shown to be associated to plasma progesterone concentrations. We hypothesize that pregnancy-related haemodilution, inducing a reduction in CSF Strong Ion Difference (SID), might have a role in the development of pregnancy-related hypocapnic alkalosis.

Samples of CSF and arterial plasma of pregnant women with gestational age > 35 weeks undergoing spinal anesthesia for elective caesarean section will be analyzed for blood gases, pH, electrolytes, osmolality, albumin and haemoglobin concentration. In addition plasma copeptin levels will be analyzed. The same measurements will be performed in fertile, non-pregnant women undergoing spinal anesthesia for elective surgery.

Enrollment: 40 estimated patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Pregnancy with gestational age > 35 weeks
• Scheduled elective cesarean section under spinal anesthesia

Exclusion criteria

• known respiratory or neurologic disease
• multiple pregnancies

Trial design

40 participants in 2 patient groups

Pregnant Women

Description:

Pregnant women with gestational age \> 35 weeks undergoing spinal anesthesia for elective cesarean section.

Treatment:

Diagnostic Test: Acid - Base characterization

Control Group

Description:

Fertile, non-pregnant women undergoing spinal anesthesia for elective surgery.

Treatment:

Diagnostic Test: Acid - Base characterization