British journal of anaesthesia
-
Randomized Controlled Trial Comparative Study Clinical Trial
Prevention of hypothermia during hip surgery: effect of passive compared with active skin surface warming.
We have measured aural canal (core) and skin temperatures, and body heat content in 45 patients undergoing elective hip arthroplasty. They received general anaesthesia which included thiopentone, vecuronium and enflurane and nitrous oxide in oxygen. ⋯ Core temperature and mean body heat content decreased significantly during surgery in groups 1 and 2 (aural canal temperature 1.5 and 1.0 degrees C, and mean body heat content 287 and 189 kJ, respectively), while in group 3 these variables remained near preoperative values (P = 0.001). Mean skin and hand temperatures decreased in the control group, increased in the active warming group and were unchanged in the passive warming group (P < 0.005), indicating that the forced heated air system was very efficient in providing thermal homeostasis during surgery, while the metallized plastic sheet was able to insulate the skin only from radiant and convective heat losses, without attenuating the reduction in core temperature.
-
Randomized Controlled Trial Clinical Trial
Influence of dose on suxamethonium-induced muscle damage.
We have examined postoperative muscle pain and early increases in serum concentrations of myoglobin after administration of suxamethonium to see if these changes were dependent on the dose of drug. Thirty ASA I and II adult patients undergoing day-case surgery received a standard anaesthetic technique, including one of three doses of suxamethonium: 0.5, 1.5 or 3.0 mg kg-1. The incidence of postoperative myalgia and the severity of fasciculations were greater after suxamethonium 1.5 mg kg-1 than after a dose of 0.5 or 3.0 mg kg-1. ⋯ Intubating conditions were significantly better with suxamethonium 1.5 or 3.0 mg kg-1 than with 0.5 mg kg-1. Changes in serum concentrations of calcium and potassium were small and similar in the three groups. We conclude that a dose of 3.0 mg kg-1 of suxamethonium provided a better combination of intubating conditions and minimal postoperative myalgia than the two lower doses.
-
We have assessed the effect of lengthening the expiratory limb of an Ayre's T-piece from 0.5 to 10 m for ventilation with a Nuffield series 200 ventilator and Newton valve, as this equipment is potentially suitable for infants and young children during anaesthesia for magnetic resonance imaging (MRI). We used lung models with compliances and resistances representative of the respiratory system with intubated trachea of a neonate, infant and child weighing 15-20 kg. The effects on ventilation were small, being greatest with the largest lung model where the longer T-piece resulted in a reduction in tidal volume from 261 to 236 ml and an increase in intrinsic and extrinsic positive end-expiratory pressure from 0.20 to 0.32 kPa and from 0.14 to 0.25 kPa, respectively. Such changes are unlikely to be clinically important and can be obviated by using the ventilator with the standard valve in children weighing 15-20 kg.
-
A postal survey of 160 members of the Neurosurgical Anaesthetists' Travelling Club was conducted in 1991 to investigate the current use of the sitting position in neurosurgery. There was a 78% response rate; at least one reply was received from every neurosurgical centre in the UK. ⋯ Thus in the period 1981-1991, the number of neurosurgical centres using the sitting position routinely, decreased by more than 50%. Current techniques of ventilation and monitoring for the sitting position are discussed briefly.
-
We describe the pregnancy and obstetric anaesthetic management of a patient with congenital tricuspid atresia who had undergone the Fontan procedure in childhood. The unique arrangement of the Fontan circulation combined with the haemodynamic alterations during pregnancy presents special anaesthetic considerations for both analgesia during labour and anaesthesia for Caesarean section.