Aerrane Inhalation Anesthetic

Generic Name: isoflurane inhalant
Dosage Form: FOR ANIMAL USE ONLY

AERRANE (isoflurane, USP) Inhalation Anesthetic For Use in Horses and Dogs

WARNING:  Not for use in horses intended for food

CAUTION:  Federal law restricts this drug to use by or on the order of a licensed veterinarian.


Aerrane Inhalation Anesthetic Description

AERRANE (isoflurane, USP) is a nonflammable, nonexplosive general inhalation anesthetic agent.  Its chemical name is 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether, and its structural formula is:


Each mL contains 99.9% isoflurane.

Some  physical constants are:

Molecular weight

184.5
Boiling point at 760 mmHg

48.5°C (uncorr.)
Refractive i n d e x n 20/D
1.2990-1.3005
Specific gravity 25°/25°C

1.496
Vapor pressure in mmHg**
20°C           238


25°C           295


30°C           367


35°C           450
**Equation for vapor pressure calculation:
log10Pvap = A + B/T

          where: A = 8.056
          B = -1664.58
          T = °C + 273.16 (Kelvin)

Partition coefficients at 37°C

Water/gas
0.61
Blood/gas
1.43
Oil/gas
90.8
Partition coefficients at 25°C - rubber and plastic

Conductive rubber/gas
62.0
Butyl rubber/gas
75.0
Polyvinyl chloride/gas
110.0
Polyethylene/gas
~2.0
Polyurethane/gas
~1.4
Polyolefin/gas
~1.1
Butyl acetate/gas
~2.5
Purity by gas chromatography
>99.9%
Lower limit of flammability in oxygen
or nitrous oxide at 9 joules/sec. and 23°C
None
Lower limit of flammability in
oxygen or nitrous oxide at
900 joules/sec. and 23°C
Greater than useful
concentration in
anesthesia.

MAC (Minimum Alveolar Concentration) is 1.31% in horses1 and 1.28 in dogs6.

Isoflurane is a clear, colorless, stable liquid containing no additives or chemical stabilizers. Isoflurane has a mildly pungent, musty, ethereal odor. Samples stored in indirect sunlight in clear, colorless glass for five years, as well as samples directly exposed for 30 hours to a 2 amp, 115 volt, 60 cycle long wave U.V. light were unchanged in composition as determined by gas chromatography. Isoflurane in one normal sodium methoxide-methanol solution, a strong base, for over six months consumed essentially no alkali, indicative of strong base stability. Isoflurane does not decompose in the presence of soda lime (at normal operating temperatures), and does not attack aluminum, tin, brass, iron or copper.


Aerrane Inhalation Anesthetic - Clinical Pharmacology

AERRANE (isoflurane, USP) is an inhalation anesthetic. Inductionand recovery from anesthesia with isoflurane are rapid.2,5  The level of anesthesia may be changed rapidly with isoflurane. Isoflurane is a profound respiratory depressant. RESPIRATION MUST BE MONITORED CLOSELY IN THE HORSE AND DOG AND SUPPORTED WHEN NECESSARY. As anesthetic dose is increased, both tidal volume and respiratory rate decrease.3,6.  This depression is partially reversed by surgical stimulation, even at deeper levels of anesthesia.

Blood pressure decreases with induction of anesthesia but returns toward normal with surgical stimulation. Progressive increases in depth of anesthesia produce corresponding decreases in blood pressure; however, heart rhythm is stable and cardiac output is maintained with controlled ventilation and normal PaCO2 despite increasing depth of anesthesia. The hypercapnia which attends spontaneous ventilation during isoflurane anesthesia increases heart rate and raises cardiac output above levels observed with controlled ventilation.3 Isoflurane does not sensitize the myocardium to exogenously administered epinephrine in the dog.


Muscle relaxation may be adequate for intra-abdominal operations at normal levels of anesthesia. However, if muscle relaxants are used to achieve greater relaxation, it should be noted that: ALL COMMONLY USED MUSCLE RELAXANTS ARE MARKEDLY POTENTIATED WITH ISOFLURANE, THE EFFECT BEING MOST PROFOUND WITH THE NONDEPOLARIZING TYPE. Neostigmine reverses the effect of nondepolarizing muscle relaxants in the presence of isoflurane but does not reverse the direct neuromuscular depression of isoflurane.

INDICATIONS

AERRANE (isoflurane, USP) is used for induction and maintenance of general anesthesia in horses and dogs.

Contraindications

AERRANE (isoflurane, USP) is contraindicated in horses and dogs with known sensitivity to isoflurane or to other halogenated agents.


Warnings

Increasing depth of anesthesia with AERRANE (isoflurane, USP) may increase hypotension and respiratory depression. The electroencephalographic pattern associated with deep anesthesia is characterized by burst suppression, spiking, and isoelectric periods.4

Since levels of anesthesia may be altered easily and rapidly, only vaporizers producing predictable percentage concentrations of isoflurane should be used (see DOSAGE AND ADMINISTRATION).


The action of nondepolarizing relaxants is augmented by isoflurane. Less than the usual amounts of these drugs should be used. If the usual amounts of nondepolarizing relaxants are given, the time for recovery from myoneural blockade will be longer in the presence of isoflurane than in the presence of other commonly used anesthetics. Not for use in horses intended for food.


Precautions

AERRANE (isoflurane, USP), like some other inhalational anesthetics, can react with desiccated carbon dioxide (CO2) absorbents to produce carbon monoxide which may result in elevated carboxyhemoglobin levels in some patients. Case reports suggest that barium hydroxide lime and soda lime become desiccated when fresh gases are passed through the CO2 absorber cannister at high flow rates over many hours or days. When a clinician suspects that CO2 absorbent may be desiccated, it should be replaced before the administration of AERRANE.

Usage in Pregnancy:

Reproduction studies have been performed in mice and rats with no evidence of fetal malformation attributable to AERRANE (isoflurane, USP). Adequate data concerning the safe use of isoflurane in pregnant and breeding horses and dogs have not been obtained.

Adverse Reactions

Hypotension, respiratory depression and arrhythmias have been reported.

Overdosage

In the event of overdosage, or what may appear to be overdosage, the following action should be taken: Stop drug administration, establish that the airway is clear and initiate assisted or controlled ventilation with pure oxygen as circumstances dictate.


Aerrane Inhalation Anesthetic Dosage and Administration

Caution: Operating rooms should be provided with adequate ventilation to prevent the accumulation of anesthetic vapors.

Premedication: A premedication regimen, which may be employed depending upon the patient status, to avert excitement during induction, might include an anticholinergic, a tranquilizer, a muscle relaxant, and a short-acting barbiturate.
Inspired Concentration: The delivered concentration of AERRANE (isoflurane, USP) should be known. Isoflurane may be vaporized using a flow-through vaporizer specifically calibrated for isoflurane. Vaporizers delivering a saturated vapor which then is diluted (e.g., Vernitrol® Vaporizer) also may be used. The delivered concentration from such a vaporizer may be calculated using the formula: 

Isoflurane contains no stabilizer. Nothing in the drug product alters calibration or operation of these vaporizers.

Induction:

Horses: Inspired concentrations of 3.0 to 5.0% isoflurane alone with oxygen following a barbiturate anesthetic induction are usually employed to induce surgical anesthesia
in the horse.

Dogs: Inspired concentrations of 2.0 to 2.5% isoflurane alone with oxygen following a barbiturate anesthetic induction are usually employed to induce surgical anesthesia in the dog.
These concentrations can be expected to produce surgical anesthesia in 5 to 10 minutes.

Maintenance: The concentration of vapor necessary to maintain anesthesia is much less than that required to induce it.

Horses: Surgical levels of anesthesia in the horse may be sustained with a 1.5 to 1.8% concentration of isoflurane in oxygen.


Dogs:
Surgical levels of anesthesia in the dog may be sustained with a 1.5 to 1.8% concentration of isoflurane in oxygen.

The level of blood pressure during maintenance is an inverse function of isoflurane concentration in the absence of other complicating problems. Excessive decreases, unless related to hypovolemia, may be due to depth of anesthesia and in such instances may be corrected by lightening the level of anesthesia. Recovery from isoflurane anesthesia is typically uneventful.2


How is Aerrane Inhalation Anesthetic Supplied

AERRANE (isoflurane, USP) is packaged in 100 mL and 250 mL
amber-colored bottles.

100 mL - NDC 10019-773-40
250 mL - NDC 10019-773-60

Storage

Store at room temperature 15°-30°C (59°-86°F).

REFERENCES

  1. Steffey, E.P., Howland, D. Jr., Giri, S. and Eger, E.I.II. Enflurane,Halothane and Isoflurane Potency in Horses. Am. J. Vet. Res.1977; 38(7):1037-1039.
  2. Auer, J.A., Garner, H.E., Amend, J.F., Hutcheson, D.P. and Salem, C.A. Recovery from Anesthesia in Ponies: A Comparative Study of the Effects of Isoflurane, Enflurane, Methoxyflurane and Halothane. Equine Vet. J. 1978; 10(1): 18-23.
  3. Steffey, E.P., and Howland, D. Jr. Comparison of Circulatory and Respiratory Effects of Isoflurane and Halothane Anesthesia in Horses. Am. J. Vet. Res. 1980;41(5): 821-825.
  4. Auer, J.A., Amend, J.F., Garner, H.E., Hutcheson, D.P. and Salem, C.A. Electroencephalographic Responses During Volatile Anesthesia in Domestic Ponies: A Comparative Study of Isoflurane, Enflurane, Methoxyflurane, and Halothane. Equine Practice 1979; 3: 130-134.
  5. Klide, A.M. Cardiopulmonary Effects of Enflurane and Isoflurane in the Dog. Am. J. Vet. Res. 1976; Vol 37, No 2: 127-131.
  6. Steffey, E.P., and Howland, D. Jr. Isoflurane Potency in the Dog and Cat. Am. J. Vet. Res. 1977; Vol 38, No 11: 1833-1836.


[NADA 135-773, Approved by FDA]
Baxter and AErrane are trademarks of Baxter International Inc.

 
Baxter logo
Manufactured for
Baxter Healthcare Corporation
Deerfield, IL 60015 USA

To report adverse reaction or obtain MSDS,
call 1 800 ANA DRUG (1-800-262-3784)
Revised: August 2006

400-226-08

PACKAGE LABELING - PRINCIPAL DISPLAY PANEL

NDC 10019-773-40
AERRANE
(isoflurane, USP)

For Use In Horses and Dogs
Caution:
Federal law restricts this drug
to use by or on order of
a licensed veterinarian.

[NADA 135-773, Approved by FDA]

Baxter logo
Manufactured for
Baxter Healthcare Corporation
Deerfield, IL 60015 USA

400-224-07

A nonflammable, nonexplosive
inhalation anesthetic
Each mL container 99.9% isofurane.

Caution:Operating rooms should be pro-
vided with adequate ventilation to prevent the
accumulation of anesthetic vapors.

Store at room temperature 15°-30°C
(59°-86°F).

IMPORTANT: See package insert for dosage
and directions for use.

To report adverse reaction or obtain MSDS,
call 1 800 ANA DRUG (1-800-262-3784)
Baxter and Aerrane are trademarks of Baxter
International Inc.

100 mL

WARNING:
Not for Use
in horses
intended
for food.

N3 10019 77340 7

AERRANE
(isoflurane, USP)

NDC 10019-773-40
6 x 100 mL Bottles

For use in Horses and Dogs

Store at room temperature 15°-30°C (59°-86°F).


Exp 10 2007

Lot A111A111

(17) 071000(10) A111A111

(01) 5 0310019 77340 2(30) 0006

Mfd. for Baxter Healthcare Corporation, Deerfield, IL 60015 USA

0001

475-235-04


AERRANE 
isoflurane inhalant
Product Information
Product Type PRESCRIPTION ANIMAL DRUG Item Code (Source) NDC:10019-773
Route of Administration RESPIRATORY (INHALATION) DEA Schedule     
Active Ingredient/Active Moiety
Ingredient Name Basis of Strength Strength
Isoflurane (Isoflurane) Isoflurane 1 mg  in 1 mL
Packaging
# Item Code Package Description
1 NDC:10019-773-40 100 mL in 1 BOTTLE, GLASS
2 NDC:10019-773-60 250 mL in 1 BOTTLE, GLASS
Marketing Information
Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date
NADA NADA135773 07/25/2008
Labeler - BAXTER HEALTHCARE CORPORATION (005083209)
Establishment
Name Address ID/FEI Operations
BAXTER HEALTHCARE SA, dba Baxter Healthcare of Puerto Rico 154731033 manufacture
Revised: 11/2010
 
BAXTER HEALTHCARE CORPORATION
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