The lure of the Lüer connector: Non-Lüer connectors in regional anaesthesia.

Health service professionals do not have perfect vigilance. There will always be the possibility that a serious untoward incident can occur due to crossover injections of medication being administered via the wrong route. The universality of the Lüer connector made it very easy to connect several medical devices for different therapeutic uses. Although this was considered a bonus, it also showed the downside as a string of incidents, leading to permanent harm and even death, occurred, warranting actions to prevent the chance of misconnections and wrong-route injections. The International Organisation for Standardisation introduced specific ISO 80 369 connectors for use in different medical systems, with the ISO 80369-6 series of standards specifically designed to improve safety in regional anaesthesia. Human error can never be completely eliminated, but the risk of a patient inadvertently suffering from an inadvertent wrong-route injection can be reduced through the use of new 'fit and no-fit' technology. This article focuses on the universality of the Lüer connector and the introduction of the newly engineered non-Lüer connectors, for specific use in medical systems.

Baseline parameters for rotational thromboelastometry in healthy labouring women: a prospective observational study.

OBJECTIVE: The aim of this study was to establish rotational thromboelastometry (ROTEM® ) baseline parameters in labouring women at term gestation. The secondary aim was to compare these reference ranges with those from previous studies on labouring women and from the manufacturer. DESIGN: A prospective, observational study. SETTING: Tertiary referral hospital. PARTICIPANTS: Healthy women in labour. METHODS: Ethics approval was granted for an opt-out recruitment approach. ROTEM® testing was performed in labouring women at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5% and 97.5% centiles for INTEM/EXTEM/FIBTEM parameters including amplitude at 5 minutes (A5), coagulation time (CT) and maximum clot firmness (MCF). MAIN OUTCOME MEASURES: ROTEM® parameters were measured in labouring women before delivery. The following tests were performed: FIBTEM, EXTEM and INTEM. RESULTS: One hundred and twenty-one women met the inclusion criteria, with a mean (± SD) age of 29.6 ± 5.4 years and median (interquartile range) gestation of 39.4 weeks (37.4-40.4 weeks). Seventy-five (62.0%) women were nulliparous and 71 (58.7%) delivered vaginally. The median and interquartile ranges for selected ROTEM® parameters were: FIBTEM A5, 21 mm (IQR 18-23 mm); EXTEM A5, 55 mm (52-58 mm); and EXTEM CT, 52 seconds (48-56 seconds). CONCLUSIONS: The FIBTEM/EXTEM/INTEM amplitudes were higher than the manufacturer's reference ranges for non-obstetric patients. The FIBTEM MCF upper and lower limits were higher and the EXTEM/INTEM CT was shorter and narrower in range. This study provides reference ranges for ROTEM® values in healthy labouring women at term gestation with uncomplicated pregnancies. TWEETABLE ABSTRACT: This is the first study to report on ROTEM® reference ranges with over 120 healthy labouring women of normal weight at term gestation.

Baseline parameters for rotational thromboelastometry (ROTEM®) in healthy pregnant Australian women: a comparison of labouring and non-labouring women at term.

BACKGROUND: Rotational thromboelastometry (ROTEM®) is a point-of-care coagulation test. Reference ranges in non-labouring women have recently been established from a cohort of women presenting for elective caesarean delivery using the recommended minimum sample size of 120. This study aimed to present baseline parameters for labouring and non-labouring women and to compare the mean values of these ROTEM® parameters. METHODS: Ethical approval was granted for an opt-out recruitment approach for labouring women and written consent was obtained from non-labouring women (data published previously). ROTEM® testing was performed in these two cohorts at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5 and 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 min (A5), coagulation time (CT), maximum clot firmness (MCF) and clot formation time (CFT). RESULTS: One hundred and twenty-one labouring and 132 non-labouring women met inclusion criteria. The mean values for selected ROTEM® parameters for labouring and non-labouring women respectively were: FIBTEM A5, 21.05 and 19.7 mm (P=0.008); EXTEM A5, 54.8 and 53.2 mm (P=0.025); and EXTEM CT, 52.2 and 53.7 s (P=0.049). Significant differences between the groups were observed in measures of clotting onset and clot firmness. CONCLUSIONS: We demonstrated a significant decrease in the mean time-to-clotting onset in labouring women compared with non-labouring women. Mean values for measures of clot firmness were greater in labouring women. In comparison to previously established ROTEM® baseline parameters for non-labouring women, this study provides evidence that there is greater hyper-coagulability in labouring women.

Baseline parameters for rotational thromboelastometry (ROTEM®) in healthy women undergoing elective caesarean delivery: a prospective observational study in Australia.

BACKGROUND: Formal reference ranges for rotational thromboelastometry (ROTEM®) in pregnancy have not been obtained in the recommended minimum sample size of 120. This prospective observational study aimed to establish baseline parameters in an Australian population of women undergoing elective caesarean delivery. The secondary aim was to compare these reference ranges with those from prior studies and the manufacturer. METHODS: Women undergoing elective caesarean delivery at term were included if they were at term, of normal body mass index and had no conditions affecting coagulation. ROTEM® reference ranges were derived by calculating the 2.5 and 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 minutes (A5), amplitude at 15 minutes (A15), coagulation time (CT), maximum clot firmness (MCF), and clot formation time (CFT). RESULTS: Of 202 women screened, 132 met the inclusion criteria, having a mean age of 32.7 ±â€¯5.0 years and median body mass index of 23.8 kg/m2 (interquartile range 21.5-26.4). The reference ranges for selected ROTEM® parameters were as follows: FIBTEM A5 (13-28 mm), FIBTEM CT (40-74 s), FIBTEM MCF (16-34 mm), EXTEM A5 (39-66 mm), EXTEM CT (43-69 s), INTEM A5 (38-63 mm). CONCLUSIONS: ROTEM® reference ranges for women with uncomplicated term pregnancies were reported as per the International Federation of Clinical Chemistry. The FIBTEM MCF and FIBTEM/EXTEM/INTEM amplitudes were higher in comparison to the manufacturer's reference ranges for the non-obstetric population. The EXTEM CT was shorter than the non-obstetric reference ranges. These ranges show an increase in coagulability during normal pregnancy compared to the non-pregnant reference ranges.

Videolaryngoscopy vs. direct laryngoscopy use by experienced anaesthetists in patients with known difficult airways: a systematic review and meta-analysis.

Experienced anaesthetists can be confronted with difficult or failed tracheal intubations. We performed a systematic review and meta-analysis to ascertain if the literature indicated if videolaryngoscopy conferred an advantage when used by experienced anaesthetists managing patients with a known difficult airway. We searched PubMed, MEDLINE, Embase and the Cochrane central register of controlled trials up to 1 January 2017. Outcome parameters extracted from studies were: first-attempt success of tracheal intubation; time to successful intubation; number of intubation attempts; Cormack and Lehane grade; use of airway adjuncts (e.g. stylet, gum elastic bougie); and complications (e.g. mucosal and dental trauma). Nine studies, including 1329 patients, fulfilled the inclusion criteria. First-attempt success was greater for all videolaryngoscopes (OR 0.34 (95%CI 0.18-0.66); p = 0.001). Use of videolaryngoscopy was associated with a significantly better view of the glottis (Cormack and Lehane grades 1 and 2 vs. 3-4, OR 0.04 (95%CI 0.01-0.15); p < 0.00001). Mucosal trauma occurred less with the use of videolaryngoscopy (OR 0.16 (95%CI 0.04-0.75); p = 0.02). Videolaryngoscopy has added value for the experienced anaesthetist, improving first-time success, the view of the glottis and reducing mucosal trauma.

Anaesthetic management of obese parturients: what is the evidence supporting practice guidelines?

Increasing rates of obesity in western populations present management difficulties for clinicians caring for obese pregnant women. Various governing bodies have published clinical guidelines for the care of obese parturients. These guidelines refer to two components of anaesthetic care: anaesthetic consultation in the antenatal period for women with a body mass index (BMI) ≥ 40 kg/m2 and the provision of early epidural analgesia in labour. These recommendations are based on the increased incidence of obstetric complications and the predicted risks and difficulties in providing anaesthetic care. The concept behind early epidural analgesia is logical-site the epidural early, use it for surgical anaesthesia and avoid general anaesthesia if surgery is required. Experts support this recommendation, but there is weak supporting evidence. It is known that the management of labour epidurals in obese women is complicated and that women with extreme obesity require higher rates of general anaesthesia. Anecdotally, anaesthetists view and apply the early epidural recommendation inconsistently and the acceptability of early epidural analgesia to pregnant women is variable. In this topic review, we critically appraise these two practice recommendations. The elements required for effective implementation in multidisciplinary maternity care are considered. We identify gaps in the current literature and suggest areas for future research. While prospective cohort studies addressing epidural extension ('top-up') in obese parturients would help inform practice, audit of local practice may better answer the question "is early epidural analgesia beneficial to obese women in my practice?".

Does objective measurement of tracheal tube cuff pressures minimise adverse effects and maintain accurate cuff pressures? A systematic review and meta-analysis.

Correct inflation pressures of the tracheal cuff are recommended to ensure adequate ventilation and prevent aspiration and adverse events. However there are conflicting views on which measurement to employ. The aim of this review was to examine whether adjustment of cuff pressure guided by objective measurement, compared with subjective measurement or observation of the pressure value alone, was able to prevent patient-related adverse effects and maintain accurate cuff pressures. A search of PubMed, Web of Science, Embase, CINAHL and ScienceDirect was conducted using keywords 'cuff pressure' and 'measure*' and related synonyms. Included studies were randomised or pseudo-randomised controlled trials investigating mechanically ventilated patients both in the intensive care unit and during surgery. Outcomes included adverse effects and the comparison of pressure measurements. Pooled analyses were performed to calculate risk ratios, effect sizes and 95% confidence intervals. Meta-analysis found preliminary evidence that adjustment of cuff pressure guided by objective measurement as compared with subjective measurement or observation of the pressure value alone, has benefit in preventing adverse effects. These included cough at two hours (odds ratio [OR] 0.42, confidence interval [CI] 0.23 to 0.79, P=0.007), hoarseness at 24 hours (OR 0.49, CI 0.31 to 0.76, P <0.002), sore throat (OR 0.73, CI 0.54 to 0.97, P <0.03), lesions of the trachea and incidences of silent aspiration (P=0.001), as well as maintaining accurate cuff pressures (Hedges' g 1.61, CI 2.69 to 0.53, P=0.003). Subjective measurement to guide adjustment or observation of the pressure value alone may lead to patient-related adverse effects and inaccuracies. It is recommended that an objective form of measurement be used.

Anaesthetists' experiences with the early labour epidural recommendation for obese parturients: a qualitative study.

Caring for obese pregnant women presents challenges for all medical professionals. Despite a lack of supporting evidence, expert opinion and international guidelines suggest early labour epidural insertion for obese women. Anecdotally this is not supported by all anaesthetists. This qualitative study explored the experiences of anaesthetists regarding early epidural analgesia in obese parturients, to answer the research question: Are anaesthetists consistent in how they apply early epidural analgesia in obese parturients? Personal in-depth interviews with 42 specialist anaesthetists working in south-east Queensland, Australia, were completed between February and April, 2015. Leximancer™ text analysis software applied a validated algorithm to the data to identify themes and concepts. The major themes were explored by the first author to answer the research question. Three major themes were identified: the demands associated with caring for obese women; concern regarding the anaesthetic technique used in obese women; and the importance of communication with obstetric staff. Disagreement regarding interpretation and application of early epidural analgesia was identified within this group of anaesthetists. These anaesthetists were inconsistent in how they interpreted and applied early epidural analgesia for obese parturients, with some questioning the validity of the practice. The combination of uncertainty, urgency and technical difficulty presented by obese parturients provoked anxiety in these clinicians, particularly the anticipation of unplanned general anaesthesia. Consistent anaesthetic practice could improve the implementation of early epidural analgesia in obese parturients.