[Ketamine: the past 30 years and its future].

INTRODUCTION

There are two isomers of ketamine: S(+) ketamine and R(-) ketamine. Effects of this drug are mediated by N-methyl-D-aspartate (NMDA), opioid and muscarinic receptors.

PHARMACOKINETICS

Due to its high lipid solubility and low protein binding, ketamine is extensively distributed in the body. Ketamine metabolism is mediated by hepatic microsomal enzymes.

EFFECTS ON BODY SYSTEMS

Ketamine causes increased intracranial pressure, bronchodilation and stimulation of cardiovascular system.

ANESTHESIA

It is used for premedication, sedation, induction and maintenance of general anesthesia. Ketamine is an ideal anesthetic agent for trauma victims, patients with hypovolemic and septic shock, patients with pulmonary diseases.

ANALGESIA

Even subanesthetic doses of ketamine have analgesic effects, so ketamine is also recommended for postoperative analgesia. Recent results show that ketamine is not always effective as an analgesic in treatment of chronic pain and that some side effects limit its use in patients with chronic pain.

INTENSIVE CARE

Combination of ketamine and midazolam can be very useful and safe for sedation and pain relief in intensive care patients, especially during ventilator management. Ketamine may be the anesthetic of choice for painful procedures in intensive care units.