Search PubMed⌕ Search

Biomedical subjects

R M Grounds

Publications and source records attributed to R M Grounds.

65 records · Page 4Linked to original sources
PubMed1987

Acute ventilatory changes during i.v. induction of anaesthesia with thiopentone or propofol in man. Studies using inductance plethysmography.

We have compared the acute ventilatory changes during induction of anaesthesia with equipotent doses of thiopentone and propofol in 12 premedicated female patients. Using ventilatory inductance plethysmography we have shown that both agents depress respiration to a similar and significant degree (P less than 0.001). However, although the functional residual capacity was reduced in patients receiving propofol, it increased slightly after induction with thiopentone (P less than 0.05).

Adult↗
PubMed1986

Intubating conditions following pre-induction priming with alcuronium.

Three priming doses of alcuronium have been investigated and, using a logistic transformation technique, the priming dose required to produce adequate intubating conditions in 99% of patients at 60 seconds following the second dose of alcuronium has been deduced. This dose, 106.5 micrograms/kg is extremely high and may be unsafe if used, since 30% of our patients complained of side effects when given a priming dose of only 50 micrograms/kg.

Adult↗
PubMed1986

Ventilatory effects of propofol during induction of anaesthesia. Comparison with thiopentone.

The ventilatory effects of induction of anaesthesia with either propofol 2.5 mg/kg or thiopentone 4.0 mg/kg have been observed in patients premedicated with either atropine alone or papaveretum and hyoscine. Induction of anaesthesia with propofol was accompanied by a greater degree of ventilatory depression which was of longer duration than following thiopentone. The effect was accentuated by the opioid premedication.

Adult↗
PubMed1986

Relationship between frequency of ventilation, airways and pulmonary artery pressures, cardiac output and tracheal tube deadspace.

Intravascular and airway pressures, cardiac output (CO) and blood gas tensions were measured in five adult patients after hepatobiliary surgery. They were ventilated at frequencies of 15, 100 and 200 breaths min-1 (bpm) with the respiratory fresh gas (RFG) supplied at the proximal and distal end of a Mallinckrodt Hi-Lo tracheal tube. The peak airway pressure (P AW) fell from 1.20 kPa at 15 bpm to 0.6 kPa at 100 bpm, rising again to 1.9 kPa at 200 bpm, and both changes were significant (P less than 0.05). The mean pulmonary artery pressure (PAMP) remained in the range 1.87-2.00 kPa (14-15 mmHg) at 15 and 100 bpm but rose to over 2.67 kPa (20 mmHg) at 200 bpm (P less than 0.05). Cardiac output, heart rate and systemic arterial pressure remained unchanged. A small but significant (P less than 0.05) reduction in PaCO2 occurred when the RFG was moved to the distal end of the tracheal tube. A theoretical analysis predicts that the minimal P AW to maintain CO2 hemostasis will occur between 30 to 100 bpm, which is reflected in the results of the present study.

Adult↗
PubMed1986

Plasma catecholamine changes during cardiopulmonary bypass: a randomised double blind comparison of trimetaphan camsylate and sodium nitroprusside.

The effects of trimetaphan camsylate and sodium nitroprusside on the catecholamine response to cardiac surgery were compared in a randomised double blind study of twelve male patients undergoing elective myocardial revascularisation. The solutions were titrated to maintain a mean arterial pressure of 70-85 mm Hg before and after bypass and less than 70 mm Hg during bypass. The rise in plasma adrenaline during cardiopulmonary bypass in the sodium nitroprusside group was significantly greater than that in the trimetaphan camsylate group. There was a smaller rise in plasma noradrenaline in the sodium nitroprusside patients but this was significantly higher than in the patients receiving trimetaphan camsylate. Administration of trimetaphan camsylate provides a simple and effective way to reduce catecholamine release during cardiopulmonary bypass.

Adult↗
PubMed1986

The relative potencies of thiopentone and propofol.

The relative potencies of the intravenous anaesthetics propofol and thiopentone have been investigated by finding the dose necessary to produce unconsciousness in approximately 30%, 50% and 80% of patients. The estimated potency of propofol to thiopentone was 1:1.604 as obtained by the probit method of analysis which estimates the logarithm of the relative potency.

Adolescent↗
PubMed1985

Comparison of infusions of propofol and methohexitone to provide light general anaesthesia during surgery with regional blockade.

General anaesthesia was induced with, and maintained by, an infusion of either propofol or methohexitone, in patients undergoing surgery with the aid of regional blockade. Both agents provided satisfactory and controllable anaesthesia. Complications were few with a similar incidence for the two drugs. Recovery from anaesthesia was significantly faster following propofol.

Adult↗
PubMed1985

The haemodynamic effects of intravenous induction. Comparison of the effects of thiopentone and propofol.

The haemodynamic changes following induction of anaesthesia with equipotent doses of propofol and thiopentone have been compared. Propofol caused a significant fall in arterial blood pressure and total peripheral resistance, with a slight fall in cardiac output. There were no changes in heart rate. Apart from an initial, but statistically insignificant increase in heart rate, similar changes were produced by thiopentone, but to a lesser degree. It is concluded that induction of anaesthesia with propofol results in acceptable haemodynamic changes, but that the agent is more depressant to the cardiovascular system than thiopentone.

Anesthesia, Intravenous↗
PubMed1985

Some studies on the properties of the intravenous anaesthetic, propofol ('Diprivan')--a review.

Four studies have been carried out on propofol in this department, one being part of a multicentre trial. The minimum induction dose in unpremedicated patients was found to be 2.5 mg/kg. Propofol has been shown to be an acceptable induction agent, although with an incidence of pain on injection which is much higher when small veins are used. When given by continuous infusion to supplement regional anaesthesia, recovery was much more rapid than with methohexitone. The potency of propofol to thiopentone has been shown to be 1:1.604. Slight falls in cardiac output occurred following propofol 2.5 mg/kg, with significant reductions in mean arterial blood pressure and systemic vascular resistance. These changes were greater than those following an equipotent dose of thiopentone 4 mg/kg.

Adjuvants, Anesthesia↗
PubMedDate not supplied

Sevoflurane.

Sevoflurane is a new inhalational anaesthetic agent which can be administered via a conventional vapourizer. Its solubility allows rapid induction, control and emergence from anaesthesia. It may find a use in day case and paediatric anaesthesia. This article reviews the agent and discusses the relevant physical properties that make it suitable for this role.

Anesthetics, Inhalation↗