Canadian journal of anaesthesia = Journal canadien d'anesthésie
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The management of a 28-year-old primigravida with placenta accreta diagnosed during Caesarean section is described. A hysterectomy was required to control massive haemorrhage, and the patient made a full recovery. The increased incidence of placenta accreta over the last three decades is thought to be associated with the concomitant increased frequency of Caesarean section, resulting in an increased incidence of placenta praevia (1.9 per cent to 3.9 per cent). ⋯ Management of placenta accreta is primarily by control of haemorrhage on delivery of the placenta. Control can be assisted by infrarenal cross-clamping of the aorta and/or intra-myometrial injection of prostaglandin F2 alpha which produces myometrial and vascular contraction. Identification of patients at increased risk, preparation for treatment and effective treatment of placenta accreta will minimize maternal morbidity and mortality.
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Randomized Controlled Trial Clinical Trial
Cardiovascular effects of non-depolarizing neuromuscular blockers in patients with aortic valve disease.
To compare haemodynamic responses associated with equipotent doses of neuromuscular blockers and high-dose fentanyl (50 micrograms.kg-1), 40 patients with aortic valve stenosis (AS) and 20 patients with aortic insufficiency (AI) were randomized to four study groups to receive the following: (1) pancuronium 0.12 mg.kg-1, (2) vecuronium 0.12 mg.kg-1, (3) atracurium 0.4 mg.kg-1, or (4) pancuronium-metocurine mixture (0.4 mg + 1.6 mg/ml): 1 ml/10 kg). Neuromuscular blockers were injected at the same time with the fentanyl; haemodynamics were recorded with the patients awake (baseline), at two minutes post-induction, and at two and five minutes after intubation. In patients with AS, pancuronium increased heart rate more than vecuronium or atracurium; heart rates were also higher with the pancuronium-metocurine mixture than with vecuronium. ⋯ Atracurium caused unexplained elevations in diastolic and mean arterial pressures which were significant when compared to vecuronium (p less than 0.01). These results in increases in PCWP; mean PA pressures and CVP were also increased. These effects of atracurium inpatients with Al need further evaluation.
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One must distinguish between what is medically safe and what is legally safe. The authors have the impression that in order to be "legally safe" one must perform a test dose. This is despite the fact that it has not been conclusively shown that the use of test doses improve the safety margin of epidural anaesthesia, when administered by a competent person, with the proper resuscitative equipment immediately available. ⋯ The literature suggests that lidocaine 1.5 per cent in dextrose 7.5 per cent should be the test dose of choice in obstetric epidural anaesthesia in an amount known to produce spinal anaesthesia (30-50 mg). The use of epinephrine in test doses in unpremedicated healthy women in active labour is neither sensitive nor specific in signalling intravascular injection, and it may also be detrimental to fetal wellbeing. Epinephrine 15 micrograms as a test dose for intravenous injection appears to create more problems than it solves.
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Randomized Controlled Trial Clinical Trial
Neostigmine, pyridostigmine and edrophonium as antagonists of deep pancuronium blockade.
To compare the ability of equipotent doses of neostigmine, pyridostigmine and edrophonium to antagonize intense pancuronium neuromuscular blockade, one hundred and twenty ASA physical status I or II patients scheduled for elective surgery received 0.06 mg.kg-1 pancuronium during a thiopentone nitrous oxide-enflurane anaesthetic. Train-of-four stimulation was applied every 12 s and the force of contraction of the adductor pollicis muscle was recorded. In the first 60 patients, spontaneous recovery was allowed until ten per cent of initial first twitch height. ⋯ These doses were given by random allocation to the next 60 patients, but at one per cent spontaneous recovery. Neostigmine, 0.04 mg.kg-1, produced a T1 of 73 +/- 4 per cent (mean +/- SEM), and a train-of-four ratio (TOF) of 39 +/- 3 per cent. This was significantly greater than with pyridostigmine, 0.2 mg.kg-1 (T1 = 50 +/- 6 per cent; TOF = 25 +/- 3 per cent), and edrophonium, 0.54 mg.kg-1 (T1 = 54 +/- 3 per cent; TOF = 17 +/- 2 per cent).(ABSTRACT TRUNCATED AT 250 WORDS)
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We reviewed anaesthetic records of 35 infants with a history of prematurity, who presented for elective herniorrhaphy. We applied a scoring system to help evaluate risk of postoperative complications. ⋯ A preoperative history of apnoea and/or moderate bronchopulmonary dysplasia appear to be valuable markers for postoperative complications. A conceptual age of 40 weeks is an acceptable lower limit of age providing there is no history of apnoea or pulmonary disease.