Propofol infusion rate does not affect local pain on injection.

BACKGROUND: Local pain at the site of an i.v. injection of propofol is a well-known problem, particularly in infants. This randomised investigator-blinded crossover study was designed to assess the effect of the i.v. bolus infusion rate on propofol-induced pain at the site of injection. METHODS: Thirty unpremedicated patients scheduled for ear-nose-throat or plastic surgery at Malmö University Hospital, Sweden, were given two consecutive 2.0 ml injections of propofol 10 mg/ml (Diprivan, AstraZeneca, Sweden/UK), at different infusion rates (0.2 or 1.0 ml/s), immediately before induction of general anesthesia. Half of the patients (n=15) received the first bolus of propofol over 2 s and the second bolus over 10 s, and the other half (n=15) had their injections in reversed order. After each injection, the patient was asked by an investigator to indicate pain intensity on a visual analog scale (VAS) and to report the times of the appearance, maximum point and disappearance of pain. The injections were given approximately 2 min apart. The investigators scoring pain intensity, as indicated by the patients on a 10-point numerical rate scale, were blinded to the order in which the injections were given, as were the patients themselves. RESULTS: There were no statistically significant differences in the incidence (both 86%) of intensity (median; 25th; 75th percentiles, in VAS units: 3.1; 1.0; 5.3 and 3.3; 1.4; 5.0, respectively) or duration (66+/-31 and 73+/-26 s, respectively) of pain between the faster (1.0 ml/s) and slower (0.2 ml/s) bolus infusion rates of propofol studied. CONCLUSIONS: We conclude that the i.v. bolus infusion rate of propofol does not influence drug-induced local pain on injection, at least not within the infusion rate interval studied. Therefore, adjusting i.v. injection speed does not seem to be a clinically useful tool for reducing the intensity or duration of propofol-induced pain at the site of administration

Propofol infusion rate does not affect local pain on injection

BACKGROUND: Local pain at the site of an i.v. injection of propofol is a well-known problem, particularly in infants. This randomised investigator-blinded crossover study was designed to assess the effect of the i.v. bolus infusion rate on propofol-induced pain at the site of injection. METHODS: Thirty unpremedicated patients scheduled for ear-nose-throat or plastic surgery at Malmö University Hospital, Sweden, were given two consecutive 2.0 ml injections of propofol 10 mg/ml (Diprivan, AstraZeneca, Sweden/UK), at different infusion rates (0.2 or 1.0 ml/s), immediately before induction of general anesthesia. Half of the patients (n=15) received the first bolus of propofol over 2 s and the second bolus over 10 s, and the other half (n=15) had their injections in reversed order. After each injection, the patient was asked by an investigator to indicate pain intensity on a visual analog scale (VAS) and to report the times of the appearance, maximum point and disappearance of pain. The injections were given approximately 2 min apart. The investigators scoring pain intensity, as indicated by the patients on a 10-point numerical rate scale, were blinded to the order in which the injections were given, as were the patients themselves. RESULTS: There were no statistically significant differences in the incidence (both 86%) of intensity (median; 25th; 75th percentiles, in VAS units: 3.1; 1.0; 5.3 and 3.3; 1.4; 5.0, respectively) or duration (66+/-31 and 73+/-26 s, respectively) of pain between the faster (1.0 ml/s) and slower (0.2 ml/s) bolus infusion rates of propofol studied. CONCLUSIONS: We conclude that the i.v. bolus infusion rate of propofol does not influence drug-induced local pain on injection, at least not within the infusion rate interval studied. Therefore, adjusting i.v. injection speed does not seem to be a clinically useful tool for reducing the intensity or duration of propofol-induced pain at the site of administration

CELSR2 is a candidate susceptibility gene in idiopathic scoliosis

A Swedish pedigree with an autosomal dominant inheritance of idiopathic scoliosis was initially studied by genetic linkage analysis, prioritising genomic regions for further analysis. This revealed a locus on chromosome 1 with a putative risk haplotype shared by all affected individuals. Two affected individuals were subsequently exome-sequenced, identifying a rare, non-synonymous variant in the CELSR2 gene. This variant is rs141489111, a c. G6859A change in exon 21 (NM_001408), leading to a predicted p. V2287I (NP_001399.1) change. This variant was found in all affected members of the pedigree, but showed reduced penetrance. Analysis of tagging variants in CELSR1-3 in a set of 1739 Swedish-Danish scoliosis cases and 1812 controls revealed significant association (p = 0.0001) to rs2281894, a common synonymous variant in CELSR2. This association was not replicated in case-control cohorts from Japan and the US. No association was found to variants in CELSR1 or CELSR3. Our findings suggest a rare variant in CELSR2 as causative for idiopathic scoliosis in a family with dominant segregation and further highlight common variation in CELSR2 in general susceptibility to idiopathic scoliosis in the Swedish-Danish population. Both variants are located in the highly conserved GAIN protein domain, which is necessary for the auto-proteolysis of CELSR2, suggesting its functional importance.Peer reviewe

Genetics and pathogenesis of idiopathic scoliosis

Idiopathic scoliosis (IS), the most common spinal deformity, affects otherwise healthy children and adolescents during growth. The aetiology is still unknown, although genetic factors are believed to be important. The present review corroborates the understanding of IS as a complex disease with a polygenic background. Presumably IS can be due to a spectrum of genetic risk variants, ranging from very rare or even private to very common. The most promising candidate genes are highlighted.Peer reviewe

Pain on injection of propofol with or without infusion of carrier fluid

BACKGROUND: Propofol, a popular intravenous (iv) anaesthetic induction agent for brief cases or day surgery, is associated with smooth induction, pleasant sleep, rapid recovery and little postoperative nausea. A major disadvantage is pain at the site of injection. The aim of the present study was to examine the influence of simultaneous iv infusion of carrier fluid on propofol-induced local pain. METHODS: Thirty patients, scheduled for ear-nose-throat or plastic surgery under general anaesthesia, were randomly allocated into two groups. Each patient had two 2 ml iv bolus injections of propofol given at two minutes' interval. In group I (n=15) the first bolus injection was given with no iv carrier fluid and the second one given with a 10 ml iv carrier fluid infused over 10 s. Correspondingly, the patients in group II (n=15) had their first injection with and their second one without the iv carrier fluid. Following each injection of propofol the patients were asked by a blinded investigator to score their pain on a 10-point visual analogue scale, and to report the appearance, maximum and disappearance of pain. After the second assessment of pain, general anaesthesia was induced with more propofol. RESULTS: Pain intensity at the site of propofol injection was found not to be influenced by simultaneous iv infusion of carrier fluid. CONCLUSION: It seems, from the results obtained here, that simultaneous iv infusion of carrier fluid has no particular effect on local pain following iv administration of propofol