Related Experiment Video

Updated: Aug 10, 2025

Standardized Model of Ventricular Fibrillation and Advanced Cardiac Life Support in Swine

Standardized Model of Ventricular Fibrillation and Advanced Cardiac Life Support in Swine

Published on: January 30, 2020

Arterial blood gas tensions during recovery in horses anesthetized with apneustic anesthesia ventilation compared

Kelsey Fisher¹, John Dodam¹, James Bailey²

¹Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA.

Veterinary Anaesthesia and Analgesia

|February 13, 2023

Abstract

Objective:

To compare PaO₂ and PaCO₂ in horses recovering from general anesthesia maintained with either apneustic anesthesia ventilation (AAV) or conventional mechanical ventilation (CMV).

Study Design:

Randomized, crossover design.

Animals:

A total of 10 healthy adult horses from a university-owned herd.

Methods:

Dorsally recumbent horses were anesthetized with isoflurane in oxygen [inspired oxygen fraction = 0.3 initially, with subsequent titration to maintain PaO₂ ≥ 85 mmHg (11.3 kPa)] and ventilated with AAV or CMV according to predefined criteria [10 mL kg^-1 tidal volume, PaCO₂ 40-45 mmHg (5.3-6.0 kPa) during CMV and < 60 mmHg (8.0 kPa) during AAV]. Horses were weaned from ventilation using a predefined protocol and transferred to a stall for unassisted recovery. Arterial blood samples were collected and analyzed at predefined time points. Tracheal oxygen insufflation at 15 L minute^-1 was provided if PaO₂ < 60 mmHg (8.0 kPa) on any analysis. Time to oxygen insufflation, first movement, sternal recumbency and standing were recorded. Data were analyzed using repeated measures anova, paired t tests and Fisher's exact test with significance defined as p < 0.05.

Results:

Data from 10 horses were analyzed. Between modes, PaO₂ was significantly higher immediately after weaning from ventilation and lower at sternal recumbency for AAV than for CMV. No PaCO₂ differences were noted between ventilation modes. All horses ventilated with CMV required supplemental oxygen, whereas three horses ventilated with AAV did not. Time to first movement was shorter with AAV. Time to oxygen insufflation was not different between ventilation modes.

Conclusions:

Although horses ventilated with AAV entered the recovery period with higher PaO₂, this advantage was not sustained during recovery. Whereas fewer horses required supplemental oxygen after AAV, the use of AAV does not preclude the need for routine supplemental oxygen administration in horses recovering from general anesthesia.

Keywords:

apneustic anesthesia ventilation conventional mechanical ventilation horse recovery

More Related Videos

Use of an Integrated Low-Flow Anesthetic Vaporizer, Ventilator, and Physiological Monitoring System for Rodents

Use of an Integrated Low-Flow Anesthetic Vaporizer, Ventilator, and Physiological Monitoring System for Rodents

Published on: July 9, 2020

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome ARDS

Surfactant Depletion Combined with Injurious Ventilation Results in a Reproducible Model of the Acute Respiratory Distress Syndrome ARDS

Published on: April 7, 2021

Related Concept Videos

Ventilatory Modes

Ventilatory Modes

Mechanical ventilators are life-saving devices that support or replace spontaneous breathing. They deliver breaths to patients through varying methods known as ventilator modes. Understanding these modes is critical for healthcare providers managing patients with respiratory failure.
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...

Acute Respiratory Failure-V

Acute Respiratory Failure-V

The treatment for acute respiratory failure varies based on factors like the underlying cause, overall health, and severity. A collaborative healthcare team is essential for early detection, often through arterial blood gas analysis. Identifying the cause is the primary goal, with treatment strategies adjusted for ventilation/perfusion (V/Q) mismatch, shunting, or diffusion impairment.
Ensure that patients are monitored continuously for their response to therapy, including changes in...

Mechanical Ventilation III: Noninvasive Ventilation

Mechanical Ventilation III: Noninvasive Ventilation

Noninvasive positive-pressure ventilation (NIPPV), continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP) are essential methods in respiratory care. These ventilation techniques offer unique benefits for patients with various respiratory conditions, providing adequate support without requiring intubation. Let's explore how each method is crucial in improving patient outcomes and enhancing respiratory therapy.
Noninvasive Positive-Pressure Ventilation...

Mechanical Ventilation I: Indication and Settings

Mechanical Ventilation I: Indication and Settings

Mechanical ventilation is a life-saving technique for managing acute respiratory failure and other respiratory complications. The process involves using a machine known as a ventilator to supply oxygen to the lungs and assist in removing carbon dioxide. It serves as a bridge to long-term mechanical ventilation or a temporary measure until ventilatory support is discontinued. The ventilator can maintain this function for a prolonged period, providing critical support for patients until they can...

Blood Studies I: ABG and VBG

Blood Studies I: ABG and VBG

Blood studies are critical in the medical field, enabling healthcare professionals to assess a patient's health status accurately. This page will focus on two significant blood studies: Arterial Blood Gas (ABG) and Venous Blood Gas (VBG).
Arterial Blood Gas (ABG)
Arterial Blood Gas (ABG) studies are crucial for assessing the lungs' ability to supply oxygen and remove carbon dioxide, reflecting the patient's ventilation status. They also help understand the kidneys' capacity to...

Assessment of Diffusion and Perfusion

Assessment of Diffusion and Perfusion

Understanding and evaluating diffusion and perfusion is critical in assessing a patient's respiratory and circulatory health. These processes play key roles in maintaining the body's internal environment, ensuring that tissues receive adequate oxygen while waste products are efficiently removed.
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this...

Articles linked to this work by shared authors, journal, and citation graph.

Improving Musculoskeletal Care Quality With a Web-Based Clinical Decision Support System in UK Primary Care: Mixed Methods Cluster-Randomized Controlled Trial.

Journal of medical Internet research·2026

The Impact of Repealing Certificate-of-Need Laws on Healthcare Spending: A Causal Analysis.

Health economics·2026

Impact of perinatal anxiety on healthcare utilisation: a matched cohort study using electronic health records in the UK.

BMJ open·2026

Family and Domestic Violence Discretion and Decision-Making Through the Perspectives of Social Workers and Victim-Survivors.

Violence against women·2026

Mucosal IgA to pre-fusion F protein predicts protection from RSV infection in a high burden setting.

Nature communications·2026

Repeated influenza vaccination results in blunting rather than back-boosting of antibody responses against A(H3N2) antigens.

Research square·2026

See all related articles