The following is a list of suggestions for anesthetizing an animal to perform PFT measurements.  

First Choice

Guinea Pig, Rat, and Mouse

For Guinea Pig, Rat, and Mouse, choose the following:

                Ketamine (50 mg/kg) + Medetomidine (0.33 mg/kg) combo

                Delivery : i.p.  1 mL/kg

For example:

                10 mL of 1 mg/mL Medetomidine

                15 mL of 100 mg/mL Ketamine

                5 mL water FI

This cocktail keeps them spontaneously breathing but allows plenty of time for the Quasi-static maneuver to complete.

Non-Human Primate (NHP)

For Monkey, choose the following:

Diprivan (Propofol) 3-15 (mL/h x kg)

The dose varies, start with 3 (mL/h x kg) but you might have to increase it up to as much as 15 (mL/h x kg)

The monkey metabolizes this substance rapidly, so recovery is also relatively quick.

Second Choice

Thiopentone sodium 100 mg/kg.

Delivery: i.p.  1 mL/kg

Third Choice

Nembutal (50 mg/mL solution of Pentobarbital)

Delivery: i.p.  0.8 mL/kg

Notes

• Pentobarbital is ok but you will get some of them breathing as you perform the test; you just have to be patient. Thiopentone tends to be better.
• It is also recommended that the i.p. injection be made to two sites, not just one. Be patient.
• Concerning the Ketamine cocktail:

Xylazine hydrochloride (Rompun) may be used in place of the Medetomidine, at the same dose.