Ketamine as analgesic for total intravenous anaesthesia with propofol

Abstract

Summary Key wordsTotal intravenous unaesthesia. Anaesthetics, intravenous; propofol, ketamine.Ketamine is a powerful analgesic, even in doses insufficient to induce anaesthesia.' It has many of the attributes of the 'ideal' analgesic agent for longer routine operations: a very high margin of safety, no irritation of the veins and no negative influence on ventilation or circulation. Its main disadvantages are that it produces hypertension and precipitates psychomimetic emergence phenomena. These effects can be mitigated by judicious medication, particularly by administering benzodiazepines. The combination of midazolam with ketamine has been recommended previously ror total intravenous anaesthesia in military surgery, general civilian practice and cardiac s~r g e r y .~-~ In this study, the combination of propofol/ketamine was compared to the combination propofol/fentanyl in a double-blind, prospective trial in patients undergolng general anaesthesia for elective surgery. Haemodynamic variables, the time to recovery and patient acceptability were compared. MethodsA prospective study of 18 patients who underwent noncardiac surgery was performed. Patients gave informed consent to a protocol approved by the medical ethics committee of our hospital. All patients were ASA grade 1 or 2 and scheduled for operations longer than 15 minutes (Table I). Patients received oral oxazepam (0.25-0.3 mg/kg) as premedication 2 hours before surgery and were allocated randomly to one of two groups to receive propofol with ketamine (n = 9) or propofol with fentanyl (n = 9) for total intravenous anaesthesia.Standard lead I1 of the electrocardiogram was monitored and an intravenous cannula inserted on arrival of the patient in the operating theatre. Heart rate was detected by electrocardiogram and calculated electronically on a beatto-beat basis. The pulse rate was timed for at least 30 seconds. One person recorded all arterial pressure measurements by auscultation (diastolic reading as Korotkoff phase V) using an anaeroid sphygomanometer previously calibrated at zero and 150 mmHg against a mercury column. Anaesthesia was induced with propofol (2 mg/kg) and either fentanyl (3 pg/kg) or ketamine (I mg/kg). Vecuronium (0.15 mg/kg) was administered. Anaesthesia was maintained with propofol 12 mg/kg/hour during the first 30 minutes, followed by 9 mg/kg/hour for 30 minutes and then 6 mg/kg/hour combined with fentanyf 1.5 pg/kg/hour or with ketamine 2 mg/kg hour. The patient's lungs were ventilated with oxygen-enriched air with an no2 of 0.35.The postinduction arterial pressure and heart rate were recorded one minute after induction, and direct laryngoscopy with a curved blade was initiated 2 minutes after induction. None of the patients received topical or intravenous lignocaine before laryngoscopy, and tracheal intubation was always accomplished within 20 seconds.

Clinical Evaluation of Total Intravenous Anesthesia Using a Combination of Propofol and Medetomidine following Anesthesia Induction with Medetomidine, Guaifenesin and Propofol for Castration in Thoroughbred Horses

“…For this reason, it has been widely used for induction and maintenance of total intravenous anesthesia (TIVA) in humans and animals [12,19]. Propofol is often used in combination with analgesics, sedatives or other anesthetics because of its poor analgesic properties and high cost [14].…”

Target controlled infusion of ketamine as analgesia for TIVA with propofol

“…4 Propofol has been shown to prevent the emergence phenomena that may occur following the use of ketamine. 4 For all drugs administered intravenously, to achieve and maintain a stable plasma concentration, it is necessary to give a loading dose, followed by a continuous infusion. This infusion replaces drug removed from the plasma by distribution and elimination and, thus, its rate declines exponentially.…”

Total intravenous anaesthesia with propofol-racemic ketamine and propofol-S-ketamine: a comparative study and haemodynamic evaluation in dogs undergoing ovariohysterectomy

“…The combination of ketamine and propofol has been used in anaesthesia induction in dogs (Lerche et al 2000) and in man, with good clinical and anaesthetic results , Guit et al 1991, Palermo et al 1991, Schüttler et al 1991, Hérnandez et al 1999). This combination showed a positive synergistic effect when compared to both drugs alone.…”

“…Despite no occurrence of cardiac index alteration a significant reduction in the systolic index as well as an increase in systemic vascular resistance index was observed in both groups. A good equilibrium between the cardiostimulating effects of ketamine and the cardiodepressor effects of propofol is reached with the combine use of both drugs (Guit et al 1991, Hui et al 1995, Lerche et al 2000.…”