Pressure-dependent Changes in Hematocrit and Plasma Volume During Anesthesia

Sahlgrenska University Hospital

Status: Unknown

Conditions: Hematocrit Change; Blood Pressure; Anesthesia

Treatments: Procedure: Maintained blood pressure; Drug: Norepinephrine

Study type: Interventional

Funder types: Other

Identifiers

NCT02412189

TDamen

Details and patient eligibility

About

The arterial blood pressure affects the ratio between filtration and reabsorption of fluids in the circulating blood volume and thereby the hematocrit. During induction of anesthesia blood pressure, hemoglobin level and hematocrit decreases. The aim of the study is to evaluate weather a maintained blood pressure with norepinephrine during anesthesia induction reduces the decrease in hematocrit.

Full description

24 patients scheduled for coronary artery bypass surgery will be included and randomized to receive either norepinephrine in the dose needed to maintain pre-anesthesia blood pressure or to a control group and receive norepinephrine only if mean arterial pressure decreases below 60 mmHg. Arterial blood gas will be analysed every ten minutes. Equal anesthesia in both groups will be monitored. No fluids will be infused. Noninvasive continuous hemoglobin measurement (SpHb) will be measured.

Enrollment: 24 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Elective coronary artery surgery patients

Exclusion criteria

• Age under 18 years
• untreated hypertension
• a reduced left ventricular systolic ejection fraction of 45 % or less
• diabetes mellitus
• former stroke and/or a known carotid artery stenosis.

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

---

24 participants in 2 patient groups

control

No Intervention group

Description:

Ordinary anesthesia, mean arterial pressure allowed to decrease to 60 mmHg. If it is lower the patients will receive a norepinephrine infusion in order to raise the mean arterial pressure to 60 mmHg.

Maintained blood pressure

Active Comparator group

Description:

Ordinary anaesthesia and maintained preanesthetic blood pressure by norepinephrine infusion

Treatment:

Drug: Norepinephrine

Procedure: Maintained blood pressure