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Anaesthetic Induction (anaesthetic + induction)
Selected AbstractsInstant centre frequency at anaesthetic induction , a new way to analyse sympathovagal balance,FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2003Edmundo Pereira De Souza Neto Abstract The instant centre frequency (ICF) of RR interval has been proposed as a global index to analyse the sympathovagal interaction in the heart. The aim of this study was to assess the ICF during anaesthesia to test if it can reliably capture the neural control of the cardiovascular system. Twenty-four ASA II or III patients scheduled for cardiac surgery were included in the study. They were allocated in two groups: control, no treatment (group 1, n = 12), and beta-adrenergic blockade by atenolol (group 2, n = 12). Spectra of pulse interval series were computed with a time,frequency method and they were divided into: very low frequency (VLF, 0.000,0.040 Hz), low frequency (LF, 0.050,0.150 Hz) and high frequency (HF, 0.160,0.500 Hz). Normalized power was obtained by dividing the cumulative power within each frequency band (LF or HF) by the sum of LF and HF; the ratio of LF/HF was also calculated. Instant centre frequency is a time-varying parameter that the evolution along time of the gravity centrum of a local spectrum. All spectral indexes were recorded at the following time points: before induction, after induction and before intubation, during intubation, and after intubation. The atenolol group had lower normalized LF and the LF/HF ratio (P < 0.05) higher HF before induction; and lower LF/HF ratio after induction and before intubation (P < 0.05). The ICF was higher in atenolol group at all times. The ICF shifted towards HF frequency after induction and before intubation and shifted towards LF during intubation in both groups. The autonomic nervous system control on the heart through the interaction of sympathetic and parasympathetic reflex mechanisms could be studied by the ICF. The ICF may assess the autonomic cardiac modulation and may provide useful information for anaesthetic management. [source] The optimal bolus dose of alfentanil for tracheal intubation during sevoflurane induction without neuromuscular blockade in day-case anaesthesiaACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2008J. Y. KIM Background: The purpose of this study was to determine the optimal bolus dose of alfentanil required to provide successful intubating conditions following inhalation induction of anaesthesia using 5% sevoflurane and 60% nitrous oxide without neuromuscular blockade in adult day-case anaesthesia. Methods: Twenty-four adults, aged 18,60 years, undergoing general anaesthesia for short ambulatory surgery were enroled into the study. After vital capacity induction, with sevoflurane 5% and 60% nitrous oxide in oxygen, pre-determined dose of alfentanil was injected over 30 s. The dose of alfentanil was determined by modified Dixon's up-and-down method (2 ,g/kg as a step size). Ninety seconds after the end of bolus administration of alfentanil, the trachea was intubated. Systolic blood pressure, heart rate and SpO2 were recorded at anaesthetic induction, before, 1 min and 3 min after intubation. Results: The bolus dose of alfentanil for successful tracheal intubation was 10.7±2.1 ,g/kg in 50% of patients during inhalation induction. From probit analysis, 50% effective dose (ED50) and ED95 values (95% confidence limits) of alfentanil were 10.7 ,g/kg (8.0,12.9 ,g/kg) and 14.9 ,g/kg (12.9,31.1 ,g/kg), respectively. Conclusions: Using the modified Dixon's up-and-down method, the bolus dose of alfentanil for successful tracheal intubation was 10.7±2.1 ,g/kg in 50% of adult patients during inhalation induction using 5% sevoflurane and 60% nitrous oxide in oxygen without neuromuscular blocking agent in day-case anaesthesia. [source] Preparation of parents by teaching of distraction techniques does not reduce child anxiety at anaesthetic induction.PEDIATRIC ANESTHESIA, Issue 9 2002A. Watson Introduction For those children having surgery, induction of anaesthesia is one of the most stressful procedures the child experiences perioperatively. Current work has failed to show a benefit of parental presence at induction of anaesthesia for all children. The reasons for lack of effect may include the high anxiety levels of some parents and also that the role for parents at their child's induction is not delineated. The main aim of this study was to see if parental preparation by teaching of distraction techniques could reduce their child's anxiety during intravenous induction of anaesthesia. Methods After ethics committee approval 40 children aged 2,10 years old, ASA status I or II undergoing daycase surgery under general anaesthesia were enrolled into the study. To avoid possible confounding factors children with a history of previous, surgery, chronic illness or developmental delay were excluded form participation. No children were given sedative premedication. After written informed consent by the parent, each child and parent was randomly assigned to an intervention or control group. Parents in the intervention group received preparation from a play specialist working on the children's surgical ward. It involved preparation for events in the anaesthetic room and instruction on methods of distraction for their child during induction using novel toys, books or blowing bubbles appropriate to the child's age. Preoperative information collected included demographic and baseline data. The temperament of the child was measured using the EASI (Emotionality, Activity, Sociability, Impulsivity) instrument of child temperament(l). In the anaesthetic room all children were planned to have intravenous induction of anaesthesia after prior application of EMLA cream. Anxiety of the child was measured by the modified Yale Preoperative Anxiety Scale (mYPAS)(2) by a blinded independent observer at three time points: entrance to the anaesthetic room, intravenous cannulation and at anaesthesia induction. Cooperation of the child was measured by the Induction Compliance Checklist (ICC) by the same observer (3). Postoperative data collected included parental satisfaction and anxiety scores measured by the Stait Trait Anxiety Inventory (STAI)(4) and at one week the behaviour of the child was measured Using the Posthospitalisation Behavioural Questionnaire (PHBQ)(5). Normally distributed data were analysed by a two-sample t-test, categorical data by Pearson's Chi-squared test and non-parametric data by the Wilcoxon rank-sum test. Results One parent withdrew after enrolment. This left 22 children in the control group and 17 in the intervention group. There were no significant differences in demographic and baseline data of the children between the two groups including ethnic origin, number of siblings, birth order of the child, recent stressful events in the child's life, previous hospital admissions and the temperament of the child. Parent demographics were also similar between groups including parent's age, sex, relationship to child and level of education. There were no significant differences in child anxiety or cooperation during induction measured by mYPAS and ICC between the control and intervention groups. More parents in the preparation group distracted their child than those without preparation but this did not reach significance. Parental anxiety immediately postinduction was similar between groups as was the level of parental satisfaction. The incidence of development of new negative postoperative behaviour of the child at one week was not significantly different between groups. Discussion This study shows that giving an active role for parents in the induction room, particularly by instructing them on distracting techniques for their child, does not reduce their child's anxiety compared to conventional parental presence. We conclude resources should not be directed at this type of parental preparation. Further work should examine the usefulness of distraction by nursing staff or play specialists during anaesthetic induction. [source] Analgesia for paediatric tonsillectomy and adenoidectomy with intramuscular clonidinePEDIATRIC ANESTHESIA, Issue 7 2002Katherine O. Freeman MD SummaryBackground: After undergoing tonsillectomy and adenoidectomy (T&A), children may experience significant pain. Clonidine, an ,2 agonist, exhibits significant analgesic properties. The current investigation sought to determine whether intramuscular (I.M.) clonidine would decrease pain in paediatric patients undergoing T&A. Methods: Thirty-nine children undergoing elective T&A were studied. Following inhalational anaesthetic induction, fentanyl (2 ,g·kg,1) was given intravenously, acetaminophen (paracetamol) (30 mg·kg,1) was given rectally and the children then randomly received an i.m. injection of either normal saline or clonidine (2,g·kg,1). Perioperative analgesic requirements in the postanaesthesia care unit and at home following hospital discharge were evaluated. Results: There were no significant demographic, analgesic consumption, haemodynamic or pain score differences between the groups. Conclusions: We do not recommend adding i.m. clonidine (2 ,g·kg,1) to the analgesic regimen of children undergoing tonsillectomy and adenoidectomy. [source] A comparison of the effect on QT interval between thiamylal and propofol during anaesthetic induction,ANAESTHESIA, Issue 7 2010U. Higashijima Summary The aim of this study was to determine the effect of thiamylal and propofol on heart rate-corrected QT (QTc) interval during anaesthetic induction. We studied 50 patients undergoing lumbar spine surgery. Patients were administered 3 ,g.kg,1 fentanyl and were randomly allocated to receive 5 mg.kg,1 thiamylal or 1.5 mg.kg,1 propofol as an induction agent. Tracheal intubation was performed after vecuronium administration. Heart rate, mean arterial pressure, bispectral index score, and 12-lead electrocardiogram were recorded at the following time points: just before (T1) and 2 min after (T2) fentanyl administration; 2 min after anaesthetic administration (T3); 2.5 min after vecuronium injection (T4); and 2 min after intubation (T5). Thiamylal prolonged (p < 0.0001), but propofol shortened (p < 0.0001), the QTc interval. [source] The use of mandibular nerve block to predict safe anaesthetic induction in patients with acute trismus*ANAESTHESIA, Issue 11 2009A. M. B. Heard Summary Acute trismus can be caused by pain, muscle spasm, swelling or mechanical obstruction. Unfortunately, the cause is not always obvious during pre-operative airway assessment. In this pilot study, we prospectively evaluated mandibular nerve block as a pre-operative tool to identify patients with reversible causes of trismus, namely pain or spasm, in order to allow safe anaesthetic induction. Six patients with unilateral fractured mandibles and trismus received a mandibular nerve block before induction of general anaesthesia. There was an increase in maximal inter-incisor gap after the blocks (median (range) distance: pre-block 16.5 (14,30) and post-block 34 (32,35) mm; p = 0.027), and no further improvement after induction of general anaesthesia (post-induction 37 (30,40) mm; p = 0.276 compared with post-block). There was an improvement in pain scores (p = 0.027), and no side-effects were detected. Pre-operative mandibular nerve blockade appears to reverse trismus caused by pain and muscle spasm, allowing the anaesthetist to decide whether awake intubation is genuinely indicated. [source] Tracheal intubating conditions after induction with sevoflurane 8% in childrenANAESTHESIA, Issue 8 2000A comparison with two intravenous techniques We studied tracheal intubating conditions in 120 healthy children, aged 3,12 years, in a blinded, randomised clinical trial. Children were randomly allocated to one of three groups: group PS, propofol 3 mg.kg,1 and succinylcholine 1 mg.kg,1 (n = 40); group PA, propofol 3 mg.kg,1 and alfentanil 10 µg.kg,1 (n = 40); group SF, sevoflurane 8% in 60% nitrous oxide in oxygen for 3 min (n = 40). Tracheal intubating conditions were graded according to ease of laryngoscopy, position of vocal cords, coughing, jaw relaxation and movement of limbs. Overall intubating conditions were acceptable in 39 of 40 children in the propofol/succinylcholine group, 21 of 40 children in the propofol/alfentanil group and 35 of 40 children in the sevoflurane group. Children receiving propofol and succinylcholine or sevoflurane had better intubating conditions overall than those given propofol and alfentanil (p < 0.01). In conclusion, anaesthetic induction and tracheal intubation using sevoflurane 8% for 3 min is a satisfactory alternative to propofol with succinylcholine in children. [source] Survey on small animal anaesthesiaAUSTRALIAN VETERINARY JOURNAL, Issue 9 2001A NICHOLSON Objective To ascertain anaesthetic practices used currently for dogs and cats in Australia. Methods A questionnaire was distributed to 4800 veterinarians throughout Australia, seeking data on numbers of dogs and cats anaesthetised per week; drug preferences for anaesthetic premedication, induction and maintenance; use of tracheal intubation, supplemental O2, nitrous oxide and anaesthetic antagonists; and types of vaporisers, breathing systems and anaesthetic monitoring devices used or available. Additional questions concerned proportions of different animal types seen in the practice, and the respondent's university and year of graduation. Results The response rate was 19%; 95% of respondents graduated from Australian universities, about half since 1985. Most responses (79%) came from mainly small animal practices. On average 16 dogs and 12 cats were anaesthetised each week. Premedication was used more often in dogs than cats, with acepromazine and atropine most favoured in both species. For anaesthetic induction, thiopentone was most preferred in dogs and alphaxalone/alphadolone in cats. Inhaled agents, especially halothane, were preferred for maintenance in both species. Most respondents usually employed tracheal intubation when using inhalational anaesthetic maintenance, but intubation rates were lower during injectable anaesthetic maintenance and a minority of respondents provided supplemental O2. Nitrous oxide was administered regularly by 13% of respondents. The agents most frequently used to speed recovery from anaesthesia were doxapram and yohimbine. The most widely used vaporisers were the Fluotec Mark III and the Stephens machine. Most (95%) respondents used a rebreathing circuit for large dogs and a non-rebreathing system was used for small dogs by 68% of respondents. Most respondents (93%) indicated some form of aid was available to monitor general anaesthesia: the three most mentioned were an apnoea alarm, oesophageal stethoscope and electrocardiogram. Conclusion Diverse approaches were evident, but there appeared to be less variation in anaesthetising dogs: premedication was more frequent and less varied in type, while thiobarbituates dominated for induction and inhalants for maintenance. Injectable maintenance techniques had substantial use in cats, but little in dogs. Evident disparity between vaporisers available and circuits used suggested either confusion in terminology or incorrect use of some vaporisers in-circuit. While most respondents used monitoring equipment or a dedicated observer to invigilate anaesthesia, the common reliance on apnoea alarms is of concern, because of unproven reliability and accuracy. [source] Mechanical bowel preparation and antibiotic prophylaxis in colorectal surgery: use by and opinions of Spanish surgeonsCOLORECTAL DISEASE, Issue 1 2009J. V. Roig Abstract Objective, Antibiotic prophylaxis (AP) and mechanical bowel preparation (MBP) previous to surgery have classically been regarded as important in colorectal surgery. The latter has recently been questioned. We evaluated opinion of Spanish surgeons about the use of these measures. Method, E-mail survey among all members of Spanish Coloproctologic Associations. Results, Of 413 participants in the survey, 131 (31.7%) responded; 87% of surgeons used cathartics (70%), enemas (2%) or both (28%) for MBP. MBP was used 60% in right colon surgery, 90% in left colon and 99% in rectal surgery. Surgeons with more case load or those who specialized in colorectal surgery used significantly less MBP; 60% of the surgeons thought that MBP made surgery easier and reduced contamination; 35% thought that it decreased wound infection (WI) and 17% thought that it prevented anastomotic leaks. For 77%, it was regarded as useful or very useful. AP was used by 99.3% of surgeons including systemic alone in 86.2% and combined with oral in 16.8%. The first dose was given 2 h before surgery by 20.2% of the surgeons, at the anaesthetic induction by 78.3% and postoperatively by 1.5%; 43% used single dose only, 44.5% extended to 24 h and 12.5% for two or more days; 95% thought that AP reduced WI and 96% considered that it was useful. Conclusion, There is general agreement on AP. MBP remained a common practice among Spanish colorectal surgeons except for right colonic resection. Surgeons with more case load and specialization used it significantly less. [source] | ||||||||||