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

Pregnancy Clinical Trial

Official title:

Effects of Pregnancy on the Physico-chemical Characteristics of Cerebrospinal Acid-base Equilibrium

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03496311
• Other study ID #: CSF acid-base in pregnancy
• Status: Recruiting
• First received: March 29, 2018
• Last updated: April 16, 2018
• Start date: April 13, 2018
• Est. completion date: April 2019

Study information

• Verified date: April 2018
• Source: Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico
• Contact: Thomas Langer, MD
• Phone: +390250320463
• Email: thomas.langer[@]unimi.it
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

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.

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 40
• Est. completion date: April 2019
• Est. primary completion date: April 2019
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Pregnancy with gestational age > 35 weeks

• Scheduled elective cesarean section under spinal anesthesia

Exclusion Criteria:

• known respiratory or neurologic disease

• multiple pregnancies

Related Conditions & MeSH terms

• Acid-Base Imbalance
• Alkalosis
• Alkalosis, Respiratory
• Cerebrospinal Fluid
• Pregnancy
• Respiratory Alkalosis

Intervention

Diagnostic Test:
• Acid - Base characterization
Samples of cerebrospinal fluid and arterial blood will be collected anaerobically to measure acid-base variables, electrolytes, albumin, progesterone and copeptin levels

Locations

Country	Name	City	State
Italy	Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico	Milan

Sponsors (2)

Lead Sponsor	Collaborator
Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico	University of Milan

Country where clinical trial is conducted

Italy, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	SID PCO2 correlation	Correlation between CSF SID and PCO2	1 day
Other	Osmolality PCO2 correlation	Correlation between CSF osmolality and PCO2	1 day
Other	Plasma progesterone PCO2 correlation	Correlation between plasma progesterone concentration and plasma PCO2	1 day
Other	CSF progesterone PCO2 correlation	Correlation between CSF progesterone concentration and CSF PCO2	1 day
Primary	Strong Ion Difference	Strong Ion Difference (expressed in milliequivalents per Liter [mEq/L]) of cerebrospinal fluid and arterial plasma	1 day
Secondary	Partial pressure of carbon dioxide (PCO2)	PCO2 (expressed in millimeters of Mercury [mmHg]) of cerebrospinal fluid and arterial plasma	1 day
Secondary	Sum of albumin (expressed in mmol/L) and Phosphates (expressed in mmol/L)	The total amount of weak non carbonic acids, i.e. the sum of albumin and phosphates (both expressed in mmol/L) of cerebrospinal fluid and arterial plasma	1 day
Secondary	Difference between cerebrospinal fluid and arterial plasma Strong Ion Difference (Delta SID)	The difference between plasma and cerebrospinal fluid SID (expressed in mEq/L) will be calculated as marker of electrolyte inbalance between these two extracellular fluid compartments. Delta SID = SIDcsf - SIDplasma	1 day
Secondary	Difference between cerebrospinal fluid and arterial plasma partial pressure of CO2 (Delta PCO2)	The difference between cerebrospinal fluid and arterial plasma PCO2 (expressed in mmHg) will be calculated as a marker of acid-base equilibrium between these two extracellular fluid compartments. Delta PCO2 = SIDplasma - SIDcsf	1 day
Secondary	Progesterone levels	Plasma and CSF Progesterone levels (expressed in ng/mL) will be measured	1 day
Secondary	Copeptin levels	Plasma copeptin levels (expressed in pmol/L) will be measured as a marker of antidiuretic hormone activity	1 day