Pain perception intensity was primarily predicted by sex with an additional role of depression and anxiety in determining VASr and VASi, respectively. Patients with high depression levels required a larger amount of tramadol.

In recent years there has been a wide use of the epidural technique not only during surgery to provide anesthesia and analgesia, but also for obstetric and trauma as well as acute, chronic and cancer pain states. Nowadays there is an increase in the number of the epidural drugs. Local anesthetics and opioids are still the pharmacological agents more widely used epidurally, nevertheless other drugs from different pharmacological classes are administered as adjuvant to local anesthetics and opioids or are in various early stages of investigation. Regarding to local anesthetics, the most recent literature focuses on the new enantiomers, ropivacaine and levobupivacaine, the efficacy of which is similar to that of bupivacaine with a reduced risk of cardiotoxicity. About opioids, the other class of drugs mainly used, the debate, in the last years, concerned the physicochemical properties of morphine and of the more recent lipophilic agents, fentanyl and sufentanil, in order to explain the main differences in efficacy and safety. Other categories of agents have been investigated for epidural administration, such as alpha(2)-adrenergic agonists clonidine and dexmedetomidine. They are being used increasingly as adjuvants to local anesthetics and opioids. Ketamine and neostigmine, the more recent studied drugs for epidural use, are still under investigation and are not part of routine clinical practice.

The use of remifentanil does not reduce POCD.

It is unclear whether shorter wave latencies of middle-latency-auditory-evoked-potentials may be associated to cognitive function other than nondeclarative memory. We investigated the presence of declarative, nondeclarative and dreaming memory in propofol-anaesthetized patients and any relationship to intraoperatively registered middle-latency-auditory-evoked-potentials. An audiotape containing one of two stories was presented to patients during anaesthesia. Patients were interviewed on dream recall immediately upon emergence from anaesthesia. Declarative and nondeclarative memories for intraoperative listening were assessed 24 h after awakening without pointing out positive findings. Six patients who reported dream recall showed an intraoperative Pa latency less than that of patients who were unable to remember any dreams (P<0.001). A high responsiveness degree of primary cortex was associated to dream recall formation during anaesthesia.

In critically ill patients, adequate sedation increases comfort, minimizes stress response and facilitates diagnostic and therapeutic procedures. Propofol (2-, 6-diisopropylphenol) is an intravenous sedative-hypnotic agent popular for sedation in the Intensive Care Unit. The favorable propofol pharmacokinetic, characterized by a three compartment linear model, allows rapid onset and short duration of action. The emergence time from sedation with propofol varies with the depth and the duration of sedation and the patient's bodyweight. Propofol causes hypotension, particularly in volume depleted patients, decreases cerebral oxygen consumption, reduces intracranial pressure and has potent anti-convulsant properties. It is a potent antioxidant, has anti-inflammatory properties and is a bronchodilator. As a consequence of these properties, propofol is being increasingly used in the management of traumatic head injury, status epilepticus, delirium tremens, status asthmaticus and in septic patients. Prolonged use (>48 h) of high doses of propofol (>66 mcg/Kg/min) has been associated with lactic acidosis, bradycardia, and lipidemia in pediatric patients. A rare complication firstly reported in pediatrics patients and also observed in adults is known as "propofol syndrome" characterized by myocardial failure, metabolic acidosis and rhabdomiolysis. Hyperkalemia and renal failure have also been associated with this syndrome. Hypertriglyceridemia and pancreatitis are uncommon complications. A large number of trials have compared the use of propofol with midazolam. Sedation with propofol is associated with adequate sedation in ICU patients, shorter weaning time and earlier tracheal extubation compared to midazolam, but not before ICU discharge.