British journal of anaesthesia
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Case Reports
Incremental spinal anaesthesia for elective Caesarean section in a patient with Eisenmenger's syndrome.
We describe a new approach to anaesthesia for elective Caesarean section in a woman with Eisenmenger's syndrome. Incremental regional anaesthesia was performed using a microspinal catheter and haemodynamic monitoring included transthoracic bioimpedance cardiography. This approach allowed the disadvantages of general anaesthesia and invasive cardiac output monitoring to be avoided.
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Randomized Controlled Trial Clinical Trial
Effects of dexmedetomidine on adrenocortical function, and the cardiovascular, endocrine and inflammatory responses in post-operative patients needing sedation in the intensive care unit.
We have compared the effects of dexmedetomidine and propofol on endocrine, metabolic, inflammatory and cardiovascular responses in patients in the intensive care unit (ICU) after major surgery. Twenty patients who were expected to require 8 h of post-operative sedation and ventilation were allocated randomly to receive either an infusion of dexmedetomidine 0.2-2.5 microg kg(-1) h(-1) or propofol 1-3 mg kg(-1) h(-1). Arterial pressure, heart rate and sequential concentrations of circulating cortisol, adrenocorticotrophic hormone (ACTH), growth hormone, prolactin, insulin, glucose and interleukin 6 were measured. ⋯ Growth hormone concentrations were significantly higher in dexmedetomidine-treated patients overall (P=0.036), but circulating concentrations remained in the physiological range. Interleukin 6 decreased in the dexmedetomidine group. We conclude that dexmedetomidine infusion does not inhibit adrenal steroidogenesis when used for short-term sedation after surgery.
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of pattern of breathing with other measures of induction of anaesthesia, using propofol, methohexital, and sevoflurane.
We assessed change of the pattern of breathing as a marker of induction of anaesthesia, using a method of maintaining spontaneous breathing throughout the induction period. We compared this index with a measure used clinically, the lash reflex, and measures used for drug investigations such as loss of grip of an object, cessation of finger tapping, and loss of arm tone. Ninety female patients (mean age 32 (17-63) yr, mean weight 63 (10) kg) were randomly allocated to induction of anaesthesia using propofol, methohexital, or sevoflurane. ⋯ The mean time to change in breathing pattern was 47 (20) s for propofol, 53 (14) s for methohexital, and 78 (29) s for sevoflurane. Although the time to achieve each end point was different, all the end points (except the lash reflex) appeared to provide similar measures of induction of anaesthesia. The pattern of breathing is an early sign of the onset of anaesthesia.
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Randomized Controlled Trial Clinical Trial
Amrinone can accelerate the cooling rate of core temperature during deliberate mild hypothermia for neurosurgical procedures.
We investigated the effects of i.v. amrinone on intraoperative changes of core temperature during deliberate mild hypothermia for neurosurgery. The patients in a control group (n=10) did not receive amrinone and patients in the amrinone group (n=10) received amrinone 5 microg kg(-1) min(-1) after a loading dose of 1.0 mg kg(-1). Anaesthesia was maintained with nitrous oxide in oxygen, propofol and fentanyl. ⋯ Tympanic membrane temperatures between 30 and 90 min after cooling were significantly lower in the amrinone group than in the control group. During cooling, the times taken to cool to 35 degrees C and to the lowest temperature were significantly shorter in the amrinone group than in the control group. These results suggest that i.v. amrinone can accelerate the cooling rate of core temperature during deliberate mild hypothermia for neurosurgical procedures.
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The primary objective of this study was to determine in vivo tissue/blood partition coefficients of propofol for use in physiological modelling of its pharmacokinetics. The sheep was used as an animal model. In the main series of experiments, crossbred ewes received a bolus of propofol 1% (Diprivan) followed by an infusion during which blood concentrations were measured at intervals. ⋯ Tissue/blood partition coefficients depend on the amount of triglyceride which accumulates in blood from the propofol vehicle; for blood, free of added triglyceride, the following coefficients were calculated: brain, 3.23; heart, 5.94; kidney, 2.46; spleen, 1.86; semimembranosus muscle, > or = 1.61; triceps muscle, > or = 1.47. Calculated tissue/water coefficients were 35 times greater. There was indirect evidence of extraction of propofol by the lungs.