British journal of anaesthesia
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of articaine and bupivacaine/lidocaine for sub-Tenon's anaesthesia in cataract extraction.
Articaine is the most widely used local anaesthetic for dental anaesthesia in Germany, Italy and The Netherlands and has recently been introduced and licensed for dental use in the UK. We have previously shown articaine to be superior to a standard mixture of bupivacaine 0.5%/lidocaine 2% for peribulbar anaesthesia. Sub-Tenon's anaesthesia arguably provides a safer method of anaesthetic delivery for cataract surgery. A blunt cannula is used in this technique, thus greatly reducing the risk of globe perforation, intrathecal injection and sight-threatening periocular haemorrhage. ⋯ Articaine 2% is safe and effective for sub-Tenon's anaesthesia and is a suitable alternative to the traditional bupivacaine 0.5%/lidocaine 2% mixture.
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Randomized Controlled Trial Clinical Trial
Effect of remifentanil infusion rate on stress response to the pre-bypass phase of paediatric cardiac surgery.
Opioids are used routinely to eliminate the stress response in the pre-bypass phase of paediatric cardiac surgery. Remifentanil is a unique opioid allowing a rapidly titratable effect. No data are available regarding a suitable remifentanil dose regimen for obtunding stress and cardiovascular responses to such surgery. ⋯ In infants and children under 5 yr, remifentanil infusions of 1.0 micro g kg(-1) min(-1) and greater can suppress the glucose increase and tachycardia associated with the pre-bypass phase of cardiac surgery, while 0.25 micro g kg(-1) min(-1) does not. Remifentanil should be used with caution in neonates with complex congenital heart disease.
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Randomized Controlled Trial Clinical Trial
Developmental pharmacokinetics of morphine and its metabolites in neonates, infants and young children.
Descriptions of the pharmacokinetics and metabolism of morphine and its metabolites in young children are scant. Previous studies have not differentiated the effects of size from those related to age during infancy. ⋯ M3G is the predominant metabolite of morphine in young children and total body morphine clearance is 80% that of adult values by 6 months. A mean steady-state serum concentration of 10 ng ml(-1) can be achieved in children after non-cardiac surgery in an intensive care unit with a morphine hydrochloride infusion of 5 micro g h(-1) kg(-1) at birth (term neonates), 8.5 micro g h(-1) kg(-1) at 1 month, 13.5 micro g h(-1) kg(-1) at 3 months and 18 micro g h(-1) kg(-1) at 1 year and 16 micro g h(-1) kg(-1) for 1- to 3-yr-old children.
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Randomized Controlled Trial Comparative Study Clinical Trial
Predicted values of propofol EC50 and sevoflurane concentration for insertion of laryngeal mask Classic and ProSeal.
A new laryngeal mask airway, the ProSeal (PLMA), is said to be more difficult to insert than the laryngeal mask airway Classic (CLMA) using propofol anaesthesia. Therefore, we expected a greater dose of propofol and sevoflurane to be required to insert the PLMA compared with the CLMA. We determined the effective concentration 50% (EC(50)) of propofol and end-tidal sevoflurane to allow insertion of the PLMA and the CLMA. ⋯ The estimated concentration of propofol and the sevoflurane concentration needed to allow insertion of the ProSeal are respectively 38 and 20% greater than those needed for insertion of the Classic LMA.
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Randomized Controlled Trial Clinical Trial
Relation between fentanyl dose and predicted EC50 of propofol for laryngeal mask insertion.
This study sought to determine the effective concentration for 50% of the attempts to secure laryngeal mask insertion (predicted EC(50LMA)) of propofol using a target-controlled infusion (Diprifusor) and investigated whether fentanyl influenced these required concentrations, respiratory rate (RR) and bispectral index (BIS). ⋯ A fentanyl dose of 0.5 micro g kg(-1) is sufficient to decrease predicted EC(50LMA) with minimum respiratory depression and without a high BIS value.