OSM: Do Changes in Plasma Osmolality Influence Ventilation?

• Sponsor: Vibeke Moen (Other)
• Overall Status: Completed
• CT.gov ID: NCT01008644
• Collaborator: (none)
• Enrollment: 26
• Location: 1
• Arms: 2
• Duration (Months): 12
• Patients Per Site Per Month: 2.2

Study Details

Study Description

Brief Summary

Primary hypothesis: osmolality changes influence the sensitivity of the respiratory center to carbon dioxide, hyponatraemia causing hyperventilation, and hypernatraemia depressing ventilation.

Secondary hypothesis: There are gender differences in the sensitivity to osmolality changes.

10 women and 10 men will on different occasions drink water or receive hypertonic saline intravenously, in order to lower or increase plasma osmolality. The women will participate during both faces of the menstruation cycle. On each occasion the subject´s sensitivity to carbon dioxide will be tested, and blood samples will be drawn for analysis of blood gases,electrolyte and osmolality.Subjects who interrupt participation before completion of all planned occasions, will be substituted, so that 10 subjects of either sex will have participated as planned. All results from all participants will be analyzed.

Condition or Disease	Intervention/Treatment	Phase
Hyponatraemia; Hypernatraemia	Other: Water; Other: Saline 3%	Early Phase 1

Detailed Description

Healthy volunteers will on different occasions be subject to reduced plasma osmolality caused by drinking water, and increased osmolality caused by intravenous infusion of hypertonic saline.Before and after each osmolality change, sensitivity to carbon dioxide will be tested by partial rebreathing through a so called Bain-system. Throughout the whole experiment heart rate, blood pressure and oxygen saturation will be recorded.Blood samples will be collected before each rebreathing test and every 20 minutes during the two hours of water or salt load. Urine will be collected and analysed.

Study Design

• Study Type: Interventional
• Actual Enrollment: 26 participants
• Allocation: Non-Randomized
• Intervention Model: Factorial Assignment
• Masking: None (Open Label)
• Primary Purpose: Basic Science
• Official Title: Do Plasma Osmolality Changes Influence Ventilation, and Are There Gender Differences?
• Study Start Date: Nov 1, 2009
• Actual Primary Completion Date: Nov 1, 2010
• Actual Study Completion Date: Nov 1, 2010

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Saline The subjects will receive saline 3% intravenously for 2 hours, the volume calculated as 0.1 ml/kg/min.	Other: Water; The subjects will drink tap water for 2 hours, volume calculated according to weight: 20ml/kg/hour.; Other Names: saline 3% ; Other: Saline 3%; The subjects will receive saline 3% intravenously for 2 hours, the volume calculated as 0.1 ml/kg/min
Experimental: Water The subjects will drink tap water for 2 hours, the volume calculated as 20ml/kg/hour	Other: Water; The subjects will drink tap water for 2 hours, volume calculated according to weight: 20ml/kg/hour.; Other Names: saline 3% ; Other: Saline 3%; The subjects will receive saline 3% intravenously for 2 hours, the volume calculated as 0.1 ml/kg/min

Outcome Measures

Primary Outcome Measures

1. pCO2 [ten minutes]

   pCO2,osmolality and sensitivity to CO2 will be recorded 10 minutes before before and 10 minutes after administering water or saline for two hours.The results will be analyzed for differences before and after osmolality changes in every single individual, and differences between females in luteal or follicular menstruation phase.

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 45 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Females with regular menstruations, males

Exclusion Criteria:

• Consumption of nicotine, BMI > 26,

• pregnancy,any hormone treatment,

• treatment with diuretics,

• diabetes or kidney disease,

• BMI > 26,

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Department of Anaesthesia and Intensive care, Kalmar County Hospital	Kalmar		Sweden	39185

Sponsors and Collaborators

• Vibeke Moen

Investigators

• Study Director: Lars Irestedt. MD PhD, Department of Anaesthesia and Intensive Care , Karolinska University Hospital, Stockholm

Study Documents (Full-Text)

None provided.

More Information

Publications

• Heenan AP, Wolfe LA. Plasma osmolality and the strong ion difference predict respiratory adaptations in pregnant and nonpregnant women. Can J Physiol Pharmacol. 2003 Sep;81(9):839-47.
• Jennings DB. The physicochemistry of [H+] and respiratory control: roles of PCO2, strong ions, and their hormonal regulators. Can J Physiol Pharmacol. 1994 Dec;72(12):1499-512. Review.
• Weissgerber TL, Wolfe LA, Hopkins WG, Davies GA. Serial respiratory adaptations and an alternate hypothesis of respiratory control in human pregnancy. Respir Physiol Neurobiol. 2006 Aug;153(1):39-53. Epub 2005 Nov 28.

• Responsible Party: Vibeke Moen, MD, Department of Anaesthesia, Kalmar County Hospital
• ClinicalTrials.gov Identifier: NCT01008644
• Other Study ID Numbers: M-126-09
• First Posted: Nov 6, 2009
• Last Update Posted: Oct 17, 2012
• Last Verified: Oct 1, 2012

• Keywords provided by Vibeke Moen, MD, Department of Anaesthesia, Kalmar County Hospital: carbon dioxide; ventilation; gender; osmolality; menstruation cycle
• Additional relevant MeSH terms: Hyponatremia; Hypernatremia

Study Results

No Results Posted as of Oct 17, 2012