The effect of ketamine on pulmonary artery pressure

Abstract

Anaesthesia for cardiac catheterisation in infants and children remains a challenge to the anaesthetist. A wide variety of methods has been advocated' but none of these has proved completely satisfactory, nor is there, as yet, a single well-recognised technique which is accepted in all centres.It is generally agreed that there should be minimal fluctuations in physiological parameters during cardiac catheterisation if false data is not to be obtained from the procedure; alterations in oxygen tension in the inspired air and intermittent positive pressure ventilation should, therefore, be avoided as far as is possible.* The introduction of ketamine has provided an anaesthetic which has proved to have advantages over others currently employed for cardiac catheterisation ; its use as a sole agent for this purpose has been described by several a~t h o r s .~-~ The advantages claimed for ketamine include its ease of administration, the rapidity of induction, the ease in maintaining an unobstructed airway and the minimal respiratory depression. Anaesthesia can be maintained for extended periods without endotracheal intubation and with the patient breathing air rather than unphysiological gas mixtures.Certain characteristic cardiovascular responses to ketamine administration have been observed and reported in both humans and anirnak6 These include an increased cardiac output, hypertension and tachycardia with little or no change in the systemic peripheral re~istance.~ These haemodynamic changes have also been noted by the authors when using ketamine in the diagnostic cardiac catheterisation Iaboratory over the past 4 years.

A comparison of 3 anesthetic protocols for 24 hours of mechanical ventilation in cats

“…32 Ketamine consistently increases mPAP in dogs, cats, and children and may be related to an increase in pulmonary vascular resistance associated with ketamine administration. 55,56 This may be clinically important to consider when anesthetizing cats with previously existing pulmonary hypertension; however, a healthy cat with normal PAP is unlikely to be significantly affected.…”

Hypoxia‐induced Vasoconstriction in Isolated Perfused Lungs exposed to Injectable or Inhalation Anesthetics

“…Ketamine is also reported to cause pulmonary hypertension. This appears to be the result of an adrenergic stimulation of capacitance vessels and increased cardiac output, rather than a direct pulmonary vasoconstrictor action ( GASSNER et al 1974). Plasma concentrations of 2.13 pg/ml have been found following administration of the average anesthetic dosage of 4.17 mg/kg b.w.…”

Administration of ketamine to children with pulmonary hypertension is safe: pro‐con debate

“…In 1974, Gassner and co‐authors reported a ‘significant rise’ in PAP following ketamine administration to unpremedicated children undergoing cardiac catheterization that was not observed in children premedicated with droperidol . This article was primarily a report of animal experiments, and unfortunately, details of study design and results pertaining to the human part of the study are lacking.…”