Anesthesia Regimes for flexiVent Studies

flexiVent experiments provide lung function outcomes with a high degree of sensitivity and reproducibility using even small subject groups. This process requires invasive interventions of either intubation (longitudinal studies) or tracheotomy (cannulation) of the subject. Adequately passive airways are essential for collecting of high-quality, reproducible data and reducing excluded data.

Airway passivity is achieved via anesthetic administration often in combination with a paralytic once a subject has been integrated with the flexiVent. Longer experiments will require re-administration, typically ¼ to ½ of the initial dose, although frequency and exact dosing will depend upon the subject background and study.


SCIREQ provides recommendations for appropriate anesthesia based upon published protocols (Figure 1). It is strongly recommended that a protocol is tested using a small number of subjects to determine how they will respond to a given dose and protocol. For instance, it is important to note the time for subjects to become fully anaesthetized, how long the animal is unresponsive, any incompatibilities between disease model and the chosen agents etc.

Choice of anesthetics and paralytics include multifactual considerations:

  • Regulatory barriers (ex. country or institution based)
  • Equipment availability (i.e. for gas-based anaesthesia)
  • Species being used
  • Disease model (ex. more fragile constitutions or co-morbidities such as inflammation)1
  • Age and strain of subjects (ex. Different strains may respond poorly to some chemicals while younger subjects tend to metabolize the compounds and exit more quickly than older ones)2,3

Table 1: SCIREQ Recommended Anesthetic and Paralytic Regimens

Some of the commonly used anesthetics and paralytics used in flexiVent experiments include ketamine, xylazine, isoflurane, pentobarital, and pancuronium bromide. Download this application note for an in depth review of these anesthetics and paralytics.

If you’re interesting in learning more about the flexiVent anesthetics and paralytic regimes in literature check out this table!

preclincial respiratory anesthesia regimes