Whole body     Head-out     Double chamber

Plethysmography is a standard method for studying pulmonary function in conscious, spontaneously breathing laboratory subjects. The barometric plethysmography technique measures flow and pressure changes that occur while the subject is breathing, before and after exposure to a drug or other challenges. It is easily adapted to various subject sizes and species, and is often used for longitudinal studies where the subjects are studied for multiple hours on successive experiment days. 


Conscious & spontaneously breathing
Ease of use
Efficient screening

Restrained versus Freely Moving

  • Whole Body

    For freely moving conscious subjects.

    In unrestrained whole body plethysmography (WBP), the spontaneously breathing subject moves freely within a small, closed plethysmograph chamber. Changes in pressure within the chamber along with the flow in and out of the box are measured using pressure transdcuers and pneumotachographs. Analyzers within the software (iox by emka TECHNOLOGIES) provide endpoints such as breathing frequency (f) and duration, estimates of tidal volume (TV), minute ventilation (MV) as well as a dimensionless quantity known as enhanced pause (Penh). Additional temperature and humidity sensors may be added to compensate thermodynamic effects in the chamber.

  • Head-out

    For restrained subjects.

    In head-out plethysmography (HOP), the subject is conscious, spontaneously breathing, and situated in a conical restraint. The conical restrainers follows the animal’s head shape and ensures that air, displaced by the chest wall motion, is isolated from the total air moving in and out of the lungs, thus permitting true flow measurements. This approach provides a true tidal volume (TV) along with measurements of breathing frequency (f) and minute ventilation (MV).

  • Double chamber

    For restrained subjects.

    In double chamber plethysmography (DCP), the head-out set-up is complemented with a head chamber, permitting delivery and containment of aerosolized compounds. A second pneumotachograph is added to the head chamber to measure both nasal flow and thoracic flow. Time shift measurement between thoracic and nasal flow allows additional outcomes to be calculated, including specific airway resistance (sRaw) and specific airway conductance (sGaw).

iox2 Software

data acquisition & real-time analysis

iox2 provides advanced data acquisition and real time analysis to manage your experiments. Powerful algorithms are integrated in this platform, allowing for customized protocols and analysis on a breath by breath basis. iox2 is a GLP compliant software that acquires, analyzes, displays, controls and stores data generated during an experiment.

features & Analyzers

  • Real-time analysis and ambulatory monitoring.
  • Flexible tuning analyzers for breath acceptance or rejection (e.g.: rejection ranges can be set for any or all parameters: TV, f, MV, PIF, PEF, etc.).
  • Automated alarms and email alerts for relevant physiologic triggers.
  • Easily configurable trends, data tables, and signal graphs to display detailed information for single or multiple subjects.
  • Replay or review data files.
  • High Definition video signals synchronized with respiratory waveforms.
  • Protocols to automate user workflow and act as experimental guidelines.
  • Apnea and cough detection.
  • Respiratory flow (RF) analyzer for ventilatory parameters.
  • Dual-chamber respiratory flow (DCRF) analyzer for specific airway resistance.
  • Multiple independent physiologic channels can be captured simultaneously for high throughput.
  • Links to emka TECHNOLOGIES and DSI telemetry.

Services & Support