Related Experiment Video
Updated: Aug 23, 2026

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome (ARDS)
Published on: April 7, 2021
Surfactant administration acutely affects cerebral and systemic hemodynamics and gas exchange in
Jeffrey R Kaiser1, C Heath Gauss, D Keith Williams
1Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. kaiserjeffrey@uams.edu
Objectives:
To determine whether surfactant administration affects cerebral and systemic hemodynamics and gas exchange in very low birth weight infants and to determine the predominant factor influencing changes in mean cerebral blood flow velocity (mCBFv) after surfactant instillation.
Study Design:
Fourteen very low birth weight infants with respiratory distress syndrome had continuous monitoring of mCBFv, Paco(2), mean arterial blood pressure (MABP), and Pao(2) before, during, and after the second dose of surfactant. Peak values and relative changes of the 4 variables for 45 minutes after surfactant were calculated. Logistic regression was used to determine the predominant factor influencing changes in mCBFv after surfactant.
Results:
Birth weight was 832 +/- 162 grams and gestational age was 25.7 +/- 1.5 weeks. The time from birth to monitoring was 6.9 +/- 1.0 hours. Mean CBFv increased 75.7% +/- 51.6% after surfactant and peaked at 14.4 +/- 5.9 minutes. Paco(2) was highly associated (OR=107.3, P <.0001) with mCBFv; as Paco(2) increased, mCBFv increased. In contrast, MABP (OR=6.7, P=.047) had less impact on mCBFv. Pao(2) was not associated with mCBFv.
Conclusions:
The increases in mCBFv after surfactant administration were predominantly due to increases in Paco(2) and not changes in MABP.
Related Concept Videos
Breathing
Acute Respiratory Failure-V
Ensure that patients are monitored continuously for their response to therapy, including changes in...
Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
Pulmonary Cycle: Exhalation
Atelectasis II: Pathophysiology
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...

